/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Portions copyright (c) 2011, Joyent, Inc. All rights reserved. */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* #pragma ident "@(#)dtrace.c 1.65 08/07/02 SMI" */ /* * DTrace - Dynamic Tracing for Solaris * * This is the implementation of the Solaris Dynamic Tracing framework * (DTrace). The user-visible interface to DTrace is described at length in * the "Solaris Dynamic Tracing Guide". The interfaces between the libdtrace * library, the in-kernel DTrace framework, and the DTrace providers are * described in the block comments in the header file. The * internal architecture of DTrace is described in the block comments in the * header file. The comments contained within the DTrace * implementation very much assume mastery of all of these sources; if one has * an unanswered question about the implementation, one should consult them * first. * * The functions here are ordered roughly as follows: * * - Probe context functions * - Probe hashing functions * - Non-probe context utility functions * - Matching functions * - Provider-to-Framework API functions * - Probe management functions * - DIF object functions * - Format functions * - Predicate functions * - ECB functions * - Buffer functions * - Enabling functions * - DOF functions * - Anonymous enabling functions * - Consumer state functions * - Helper functions * - Hook functions * - Driver cookbook functions * * Each group of functions begins with a block comment labelled the "DTrace * [Group] Functions", allowing one to find each block by searching forward * on capital-f functions. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern uint32_t pmap_find_phys(void *, uint64_t); extern boolean_t pmap_valid_page(uint32_t); extern void OSKextRegisterKextsWithDTrace(void); extern kmod_info_t g_kernel_kmod_info; /* Solaris proc_t is the struct. Darwin's proc_t is a pointer to it. */ #define proc_t struct proc /* Steer clear of the Darwin typedef for proc_t */ #define t_predcache t_dtrace_predcache /* Cosmetic. Helps readability of thread.h */ extern void dtrace_suspend(void); extern void dtrace_resume(void); extern void dtrace_init(void); extern void helper_init(void); extern void fasttrap_init(void); extern void dtrace_lazy_dofs_duplicate(proc_t *, proc_t *); extern void dtrace_lazy_dofs_destroy(proc_t *); extern void dtrace_postinit(void); #include "../../../osfmk/chud/chud_dtrace.h" extern kern_return_t chudxnu_dtrace_callback (uint64_t selector, uint64_t *args, uint32_t count); /* Import this function to retrieve the physical memory. */ extern int kernel_sysctlbyname(const char *name, void *oldp, size_t *oldlenp, void *newp, size_t newlen); /* * DTrace Tunable Variables * * The following variables may be dynamically tuned by using sysctl(8), the * variables being stored in the kern.dtrace namespace. For example: * sysctl kern.dtrace.dof_maxsize = 1048575 # 1M * * In general, the only variables that one should be tuning this way are those * that affect system-wide DTrace behavior, and for which the default behavior * is undesirable. Most of these variables are tunable on a per-consumer * basis using DTrace options, and need not be tuned on a system-wide basis. * When tuning these variables, avoid pathological values; while some attempt * is made to verify the integrity of these variables, they are not considered * part of the supported interface to DTrace, and they are therefore not * checked comprehensively. */ uint64_t dtrace_buffer_memory_maxsize = 0; /* initialized in dtrace_init */ uint64_t dtrace_buffer_memory_inuse = 0; int dtrace_destructive_disallow = 0; dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024); size_t dtrace_difo_maxsize = (256 * 1024); dtrace_optval_t dtrace_dof_maxsize = (384 * 1024); size_t dtrace_global_maxsize = (16 * 1024); size_t dtrace_actions_max = (16 * 1024); size_t dtrace_retain_max = 1024; dtrace_optval_t dtrace_helper_actions_max = 32; dtrace_optval_t dtrace_helper_providers_max = 64; dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024); size_t dtrace_strsize_default = 256; dtrace_optval_t dtrace_cleanrate_default = 990099000; /* 1.1 hz */ dtrace_optval_t dtrace_cleanrate_min = 20000000; /* 50 hz */ dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */ dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */ dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */ dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */ dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */ dtrace_optval_t dtrace_nspec_default = 1; dtrace_optval_t dtrace_specsize_default = 32 * 1024; dtrace_optval_t dtrace_stackframes_default = 20; dtrace_optval_t dtrace_ustackframes_default = 20; dtrace_optval_t dtrace_jstackframes_default = 50; dtrace_optval_t dtrace_jstackstrsize_default = 512; int dtrace_msgdsize_max = 128; hrtime_t dtrace_chill_max = 500 * (NANOSEC / MILLISEC); /* 500 ms */ hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */ int dtrace_devdepth_max = 32; int dtrace_err_verbose; int dtrace_provide_private_probes = 0; hrtime_t dtrace_deadman_interval = NANOSEC; hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC; hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC; /* * DTrace External Variables * * As dtrace(7D) is a kernel module, any DTrace variables are obviously * available to DTrace consumers via the backtick (`) syntax. One of these, * dtrace_zero, is made deliberately so: it is provided as a source of * well-known, zero-filled memory. While this variable is not documented, * it is used by some translators as an implementation detail. */ const char dtrace_zero[256] = { 0 }; /* zero-filled memory */ unsigned int dtrace_max_cpus = 0; /* number of enabled cpus */ /* * DTrace Internal Variables */ static dev_info_t *dtrace_devi; /* device info */ static vmem_t *dtrace_arena; /* probe ID arena */ static vmem_t *dtrace_minor; /* minor number arena */ static taskq_t *dtrace_taskq; /* task queue */ static dtrace_probe_t **dtrace_probes; /* array of all probes */ static int dtrace_nprobes; /* number of probes */ static dtrace_provider_t *dtrace_provider; /* provider list */ static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */ static int dtrace_opens; /* number of opens */ static int dtrace_helpers; /* number of helpers */ static void *dtrace_softstate; /* softstate pointer */ static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */ static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */ static dtrace_hash_t *dtrace_byname; /* probes hashed by name */ static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */ static int dtrace_toxranges; /* number of toxic ranges */ static int dtrace_toxranges_max; /* size of toxic range array */ static dtrace_anon_t dtrace_anon; /* anonymous enabling */ static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */ static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */ static kthread_t *dtrace_panicked; /* panicking thread */ static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */ static dtrace_genid_t dtrace_probegen; /* current probe generation */ static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */ static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */ static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */ static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */ static int dtrace_dof_mode; /* See dtrace_impl.h for a description of Darwin's dof modes. */ /* * This does't quite fit as an internal variable, as it must be accessed in * fbt_provide and sdt_provide. Its clearly not a dtrace tunable variable either... */ int dtrace_kernel_symbol_mode; /* See dtrace_impl.h for a description of Darwin's kernel symbol modes. */ /* * To save memory, some common memory allocations are given a * unique zone. For example, dtrace_probe_t is 72 bytes in size, * which means it would fall into the kalloc.128 bucket. With * 20k elements allocated, the space saved is substantial. */ struct zone *dtrace_probe_t_zone; static int dtrace_module_unloaded(struct kmod_info *kmod); /* * DTrace Locking * DTrace is protected by three (relatively coarse-grained) locks: * * (1) dtrace_lock is required to manipulate essentially any DTrace state, * including enabling state, probes, ECBs, consumer state, helper state, * etc. Importantly, dtrace_lock is _not_ required when in probe context; * probe context is lock-free -- synchronization is handled via the * dtrace_sync() cross call mechanism. * * (2) dtrace_provider_lock is required when manipulating provider state, or * when provider state must be held constant. * * (3) dtrace_meta_lock is required when manipulating meta provider state, or * when meta provider state must be held constant. * * The lock ordering between these three locks is dtrace_meta_lock before * dtrace_provider_lock before dtrace_lock. (In particular, there are * several places where dtrace_provider_lock is held by the framework as it * calls into the providers -- which then call back into the framework, * grabbing dtrace_lock.) * * There are two other locks in the mix: mod_lock and cpu_lock. With respect * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical * role as a coarse-grained lock; it is acquired before both of these locks. * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must * be acquired _between_ dtrace_meta_lock and any other DTrace locks. * mod_lock is similar with respect to dtrace_provider_lock in that it must be * acquired _between_ dtrace_provider_lock and dtrace_lock. */ /* * APPLE NOTE: * * For porting purposes, all kmutex_t vars have been changed * to lck_mtx_t, which require explicit initialization. * * kmutex_t becomes lck_mtx_t * mutex_enter() becomes lck_mtx_lock() * mutex_exit() becomes lck_mtx_unlock() * * Lock asserts are changed like this: * * ASSERT(MUTEX_HELD(&cpu_lock)); * becomes: * lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); * */ static lck_mtx_t dtrace_lock; /* probe state lock */ static lck_mtx_t dtrace_provider_lock; /* provider state lock */ static lck_mtx_t dtrace_meta_lock; /* meta-provider state lock */ static lck_rw_t dtrace_dof_mode_lock; /* dof mode lock */ /* * DTrace Provider Variables * * These are the variables relating to DTrace as a provider (that is, the * provider of the BEGIN, END, and ERROR probes). */ static dtrace_pattr_t dtrace_provider_attr = { { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN }, { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON }, }; static void dtrace_nullop(void) {} static int dtrace_enable_nullop(void) { return (0); } static dtrace_pops_t dtrace_provider_ops = { (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop, (void (*)(void *, struct modctl *))dtrace_nullop, (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop, (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, (void (*)(void *, dtrace_id_t, void *))dtrace_nullop, NULL, NULL, NULL, (void (*)(void *, dtrace_id_t, void *))dtrace_nullop }; static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */ static dtrace_id_t dtrace_probeid_end; /* special END probe */ dtrace_id_t dtrace_probeid_error; /* special ERROR probe */ /* * DTrace Helper Tracing Variables */ uint32_t dtrace_helptrace_next = 0; uint32_t dtrace_helptrace_nlocals; char *dtrace_helptrace_buffer; size_t dtrace_helptrace_bufsize = 512 * 1024; #if DEBUG int dtrace_helptrace_enabled = 1; #else int dtrace_helptrace_enabled = 0; #endif /* * DTrace Error Hashing * * On DEBUG kernels, DTrace will track the errors that has seen in a hash * table. This is very useful for checking coverage of tests that are * expected to induce DIF or DOF processing errors, and may be useful for * debugging problems in the DIF code generator or in DOF generation . The * error hash may be examined with the ::dtrace_errhash MDB dcmd. */ #if DEBUG static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ]; static const char *dtrace_errlast; static kthread_t *dtrace_errthread; static lck_mtx_t dtrace_errlock; #endif /* * DTrace Macros and Constants * * These are various macros that are useful in various spots in the * implementation, along with a few random constants that have no meaning * outside of the implementation. There is no real structure to this cpp * mishmash -- but is there ever? */ #define DTRACE_HASHSTR(hash, probe) \ dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs))) #define DTRACE_HASHNEXT(hash, probe) \ (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs) #define DTRACE_HASHPREV(hash, probe) \ (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs) #define DTRACE_HASHEQ(hash, lhs, rhs) \ (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \ *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0) #define DTRACE_AGGHASHSIZE_SLEW 17 #define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3) /* * The key for a thread-local variable consists of the lower 61 bits of the * current_thread(), plus the 3 bits of the highest active interrupt above LOCK_LEVEL. * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never * equal to a variable identifier. This is necessary (but not sufficient) to * assure that global associative arrays never collide with thread-local * variables. To guarantee that they cannot collide, we must also define the * order for keying dynamic variables. That order is: * * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ] * * Because the variable-key and the tls-key are in orthogonal spaces, there is * no way for a global variable key signature to match a thread-local key * signature. */ #if defined (__x86_64__) /* FIXME: two function calls!! */ #define DTRACE_TLS_THRKEY(where) { \ uint_t intr = ml_at_interrupt_context(); /* Note: just one measly bit */ \ uint64_t thr = (uintptr_t)current_thread(); \ ASSERT(intr < (1 << 3)); \ (where) = ((thr + DIF_VARIABLE_MAX) & \ (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \ } #else #error Unknown architecture #endif #define DT_BSWAP_8(x) ((x) & 0xff) #define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8)) #define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16)) #define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32)) #define DT_MASK_LO 0x00000000FFFFFFFFULL #define DTRACE_STORE(type, tomax, offset, what) \ *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what); #define DTRACE_ALIGNCHECK(addr, size, flags) \ if (addr & (MIN(size,4) - 1)) { \ *flags |= CPU_DTRACE_BADALIGN; \ cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \ return (0); \ } /* * Test whether a range of memory starting at testaddr of size testsz falls * within the range of memory described by addr, sz. We take care to avoid * problems with overflow and underflow of the unsigned quantities, and * disallow all negative sizes. Ranges of size 0 are allowed. */ #define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \ ((testaddr) - (baseaddr) < (basesz) && \ (testaddr) + (testsz) - (baseaddr) <= (basesz) && \ (testaddr) + (testsz) >= (testaddr)) /* * Test whether alloc_sz bytes will fit in the scratch region. We isolate * alloc_sz on the righthand side of the comparison in order to avoid overflow * or underflow in the comparison with it. This is simpler than the INRANGE * check above, because we know that the dtms_scratch_ptr is valid in the * range. Allocations of size zero are allowed. */ #define DTRACE_INSCRATCH(mstate, alloc_sz) \ ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \ (mstate)->dtms_scratch_ptr >= (alloc_sz)) #define RECOVER_LABEL(bits) dtraceLoadRecover##bits: #if defined (__x86_64__) #define DTRACE_LOADFUNC(bits) \ /*CSTYLED*/ \ uint##bits##_t dtrace_load##bits(uintptr_t addr); \ \ uint##bits##_t \ dtrace_load##bits(uintptr_t addr) \ { \ size_t size = bits / NBBY; \ /*CSTYLED*/ \ uint##bits##_t rval = 0; \ int i; \ volatile uint16_t *flags = (volatile uint16_t *) \ &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; \ \ DTRACE_ALIGNCHECK(addr, size, flags); \ \ for (i = 0; i < dtrace_toxranges; i++) { \ if (addr >= dtrace_toxrange[i].dtt_limit) \ continue; \ \ if (addr + size <= dtrace_toxrange[i].dtt_base) \ continue; \ \ /* \ * This address falls within a toxic region; return 0. \ */ \ *flags |= CPU_DTRACE_BADADDR; \ cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \ return (0); \ } \ \ { \ volatile vm_offset_t recover = (vm_offset_t)&&dtraceLoadRecover##bits; \ *flags |= CPU_DTRACE_NOFAULT; \ recover = dtrace_set_thread_recover(current_thread(), recover); \ /*CSTYLED*/ \ /* \ * PR6394061 - avoid device memory that is unpredictably \ * mapped and unmapped \ */ \ if (pmap_valid_page(pmap_find_phys(kernel_pmap, addr))) \ rval = *((volatile uint##bits##_t *)addr); \ RECOVER_LABEL(bits); \ (void)dtrace_set_thread_recover(current_thread(), recover); \ *flags &= ~CPU_DTRACE_NOFAULT; \ } \ \ return (rval); \ } #else /* all other architectures */ #error Unknown Architecture #endif #ifdef __LP64__ #define dtrace_loadptr dtrace_load64 #else #define dtrace_loadptr dtrace_load32 #endif #define DTRACE_DYNHASH_FREE 0 #define DTRACE_DYNHASH_SINK 1 #define DTRACE_DYNHASH_VALID 2 #define DTRACE_MATCH_FAIL -1 #define DTRACE_MATCH_NEXT 0 #define DTRACE_MATCH_DONE 1 #define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0') #define DTRACE_STATE_ALIGN 64 #define DTRACE_FLAGS2FLT(flags) \ (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \ ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \ ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \ ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \ ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \ ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \ ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \ ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \ ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \ DTRACEFLT_UNKNOWN) #define DTRACEACT_ISSTRING(act) \ ((act)->dta_kind == DTRACEACT_DIFEXPR && \ (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) static size_t dtrace_strlen(const char *, size_t); static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id); static void dtrace_enabling_provide(dtrace_provider_t *); static int dtrace_enabling_match(dtrace_enabling_t *, int *); static void dtrace_enabling_matchall(void); static dtrace_state_t *dtrace_anon_grab(void); static uint64_t dtrace_helper(int, dtrace_mstate_t *, dtrace_state_t *, uint64_t, uint64_t); static dtrace_helpers_t *dtrace_helpers_create(proc_t *); static void dtrace_buffer_drop(dtrace_buffer_t *); static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t, dtrace_state_t *, dtrace_mstate_t *); static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t, dtrace_optval_t); static int dtrace_ecb_create_enable(dtrace_probe_t *, void *); static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *); /* * DTrace sysctl handlers * * These declarations and functions are used for a deeper DTrace configuration. * Most of them are not per-consumer basis and may impact the other DTrace * consumers. Correctness may not be supported for all the variables, so you * should be careful about what values you are using. */ SYSCTL_DECL(_kern_dtrace); SYSCTL_NODE(_kern, OID_AUTO, dtrace, CTLFLAG_RW | CTLFLAG_LOCKED, 0, "dtrace"); static int sysctl_dtrace_err_verbose SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2) int changed, error; int value = *(int *) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, &changed); if (error || !changed) return (error); if (value != 0 && value != 1) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_err_verbose = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.err_verbose * * Set DTrace verbosity when an error occured (0 = disabled, 1 = enabld). * Errors are reported when a DIFO or a DOF has been rejected by the kernel. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, err_verbose, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_err_verbose, 0, sysctl_dtrace_err_verbose, "I", "dtrace error verbose"); static int sysctl_dtrace_buffer_memory_maxsize SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2, req) int changed, error; uint64_t value = *(uint64_t *) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, &changed); if (error || !changed) return (error); if (value <= dtrace_buffer_memory_inuse) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_buffer_memory_maxsize = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.buffer_memory_maxsize * * Set DTrace maximal size in bytes used by all the consumers' state buffers. By default * the limit is PHYS_MEM / 3 for *all* consumers. Attempting to set a null, a negative value * or a value <= to dtrace_buffer_memory_inuse will result in a failure. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, buffer_memory_maxsize, CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_buffer_memory_maxsize, 0, sysctl_dtrace_buffer_memory_maxsize, "Q", "dtrace state buffer memory maxsize"); /* * kern.dtrace.buffer_memory_inuse * * Current state buffer memory used, in bytes, by all the DTrace consumers. * This value is read-only. */ SYSCTL_QUAD(_kern_dtrace, OID_AUTO, buffer_memory_inuse, CTLFLAG_RD | CTLFLAG_LOCKED, &dtrace_buffer_memory_inuse, "dtrace state buffer memory in-use"); static int sysctl_dtrace_difo_maxsize SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2, req) int changed, error; size_t value = *(size_t*) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, &changed); if (error || !changed) return (error); if (value <= 0) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_difo_maxsize = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.difo_maxsize * * Set the DIFO max size in bytes, check the definition of dtrace_difo_maxsize * to get the default value. Attempting to set a null or negative size will * result in a failure. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, difo_maxsize, CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_difo_maxsize, 0, sysctl_dtrace_difo_maxsize, "Q", "dtrace difo maxsize"); static int sysctl_dtrace_dof_maxsize SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2, req) int changed, error; dtrace_optval_t value = *(dtrace_optval_t *) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, &changed); if (error || !changed) return (error); if (value <= 0) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_dof_maxsize = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.dof_maxsize * * Set the DOF max size in bytes, check the definition of dtrace_dof_maxsize to * get the default value. Attempting to set a null or negative size will result * in a failure. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, dof_maxsize, CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_dof_maxsize, 0, sysctl_dtrace_dof_maxsize, "Q", "dtrace dof maxsize"); static int sysctl_dtrace_global_maxsize SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2, req) int changed, error; dtrace_optval_t value = *(dtrace_optval_t*) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, &changed); if (error || !changed) return (error); if (value <= 0) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_global_maxsize = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.global_maxsize * * Set the global variable max size in bytes, check the definition of * dtrace_global_maxsize to get the default value. Attempting to set a null or * negative size will result in a failure. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, global_maxsize, CTLTYPE_QUAD | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_global_maxsize, 0, sysctl_dtrace_global_maxsize, "Q", "dtrace global maxsize"); static int sysctl_dtrace_provide_private_probes SYSCTL_HANDLER_ARGS { #pragma unused(oidp, arg2) int error; int value = *(int *) arg1; error = sysctl_io_number(req, value, sizeof(value), &value, NULL); if (error) return (error); if (value != 0 && value != 1) return (ERANGE); lck_mtx_lock(&dtrace_lock); dtrace_provide_private_probes = value; lck_mtx_unlock(&dtrace_lock); return (0); } /* * kern.dtrace.provide_private_probes * * Set whether the providers must provide the private probes. This is * mainly used by the FBT provider to request probes for the private/static * symbols. */ SYSCTL_PROC(_kern_dtrace, OID_AUTO, provide_private_probes, CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_LOCKED, &dtrace_provide_private_probes, 0, sysctl_dtrace_provide_private_probes, "I", "provider must provide the private probes"); /* * DTrace Probe Context Functions * * These functions are called from probe context. Because probe context is * any context in which C may be called, arbitrarily locks may be held, * interrupts may be disabled, we may be in arbitrary dispatched state, etc. * As a result, functions called from probe context may only call other DTrace * support functions -- they may not interact at all with the system at large. * (Note that the ASSERT macro is made probe-context safe by redefining it in * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary * loads are to be performed from probe context, they _must_ be in terms of * the safe dtrace_load*() variants. * * Some functions in this block are not actually called from probe context; * for these functions, there will be a comment above the function reading * "Note: not called from probe context." */ int dtrace_assfail(const char *a, const char *f, int l) { panic("dtrace: assertion failed: %s, file: %s, line: %d", a, f, l); /* * We just need something here that even the most clever compiler * cannot optimize away. */ return (a[(uintptr_t)f]); } /* * Atomically increment a specified error counter from probe context. */ static void dtrace_error(uint32_t *counter) { /* * Most counters stored to in probe context are per-CPU counters. * However, there are some error conditions that are sufficiently * arcane that they don't merit per-CPU storage. If these counters * are incremented concurrently on different CPUs, scalability will be * adversely affected -- but we don't expect them to be white-hot in a * correctly constructed enabling... */ uint32_t oval, nval; do { oval = *counter; if ((nval = oval + 1) == 0) { /* * If the counter would wrap, set it to 1 -- assuring * that the counter is never zero when we have seen * errors. (The counter must be 32-bits because we * aren't guaranteed a 64-bit compare&swap operation.) * To save this code both the infamy of being fingered * by a priggish news story and the indignity of being * the target of a neo-puritan witch trial, we're * carefully avoiding any colorful description of the * likelihood of this condition -- but suffice it to * say that it is only slightly more likely than the * overflow of predicate cache IDs, as discussed in * dtrace_predicate_create(). */ nval = 1; } } while (dtrace_cas32(counter, oval, nval) != oval); } /* * Use the DTRACE_LOADFUNC macro to define functions for each of loading a * uint8_t, a uint16_t, a uint32_t and a uint64_t. */ DTRACE_LOADFUNC(8) DTRACE_LOADFUNC(16) DTRACE_LOADFUNC(32) DTRACE_LOADFUNC(64) static int dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate) { if (dest < mstate->dtms_scratch_base) return (0); if (dest + size < dest) return (0); if (dest + size > mstate->dtms_scratch_ptr) return (0); return (1); } static int dtrace_canstore_statvar(uint64_t addr, size_t sz, dtrace_statvar_t **svars, int nsvars) { int i; for (i = 0; i < nsvars; i++) { dtrace_statvar_t *svar = svars[i]; if (svar == NULL || svar->dtsv_size == 0) continue; if (DTRACE_INRANGE(addr, sz, svar->dtsv_data, svar->dtsv_size)) return (1); } return (0); } /* * Check to see if the address is within a memory region to which a store may * be issued. This includes the DTrace scratch areas, and any DTrace variable * region. The caller of dtrace_canstore() is responsible for performing any * alignment checks that are needed before stores are actually executed. */ static int dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) { /* * First, check to see if the address is in scratch space... */ if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base, mstate->dtms_scratch_size)) return (1); /* * Now check to see if it's a dynamic variable. This check will pick * up both thread-local variables and any global dynamically-allocated * variables. */ if (DTRACE_INRANGE(addr, sz, (uintptr_t)vstate->dtvs_dynvars.dtds_base, vstate->dtvs_dynvars.dtds_size)) { dtrace_dstate_t *dstate = &vstate->dtvs_dynvars; uintptr_t base = (uintptr_t)dstate->dtds_base + (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t)); uintptr_t chunkoffs; /* * Before we assume that we can store here, we need to make * sure that it isn't in our metadata -- storing to our * dynamic variable metadata would corrupt our state. For * the range to not include any dynamic variable metadata, * it must: * * (1) Start above the hash table that is at the base of * the dynamic variable space * * (2) Have a starting chunk offset that is beyond the * dtrace_dynvar_t that is at the base of every chunk * * (3) Not span a chunk boundary * */ if (addr < base) return (0); chunkoffs = (addr - base) % dstate->dtds_chunksize; if (chunkoffs < sizeof (dtrace_dynvar_t)) return (0); if (chunkoffs + sz > dstate->dtds_chunksize) return (0); return (1); } /* * Finally, check the static local and global variables. These checks * take the longest, so we perform them last. */ if (dtrace_canstore_statvar(addr, sz, vstate->dtvs_locals, vstate->dtvs_nlocals)) return (1); if (dtrace_canstore_statvar(addr, sz, vstate->dtvs_globals, vstate->dtvs_nglobals)) return (1); return (0); } /* * Convenience routine to check to see if the address is within a memory * region in which a load may be issued given the user's privilege level; * if not, it sets the appropriate error flags and loads 'addr' into the * illegal value slot. * * DTrace subroutines (DIF_SUBR_*) should use this helper to implement * appropriate memory access protection. */ static int dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) { volatile uint64_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval; /* * If we hold the privilege to read from kernel memory, then * everything is readable. */ if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) return (1); /* * You can obviously read that which you can store. */ if (dtrace_canstore(addr, sz, mstate, vstate)) return (1); /* * We're allowed to read from our own string table. */ if (DTRACE_INRANGE(addr, sz, (uintptr_t)mstate->dtms_difo->dtdo_strtab, mstate->dtms_difo->dtdo_strlen)) return (1); DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV); *illval = addr; return (0); } /* * Convenience routine to check to see if a given string is within a memory * region in which a load may be issued given the user's privilege level; * this exists so that we don't need to issue unnecessary dtrace_strlen() * calls in the event that the user has all privileges. */ static int dtrace_strcanload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) { size_t strsz; /* * If we hold the privilege to read from kernel memory, then * everything is readable. */ if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) return (1); strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr, sz); if (dtrace_canload(addr, strsz, mstate, vstate)) return (1); return (0); } /* * Convenience routine to check to see if a given variable is within a memory * region in which a load may be issued given the user's privilege level. */ static int dtrace_vcanload(void *src, dtrace_diftype_t *type, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) { size_t sz; ASSERT(type->dtdt_flags & DIF_TF_BYREF); /* * If we hold the privilege to read from kernel memory, then * everything is readable. */ if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) return (1); if (type->dtdt_kind == DIF_TYPE_STRING) sz = dtrace_strlen(src, vstate->dtvs_state->dts_options[DTRACEOPT_STRSIZE]) + 1; else sz = type->dtdt_size; return (dtrace_canload((uintptr_t)src, sz, mstate, vstate)); } /* * Compare two strings using safe loads. */ static int dtrace_strncmp(char *s1, char *s2, size_t limit) { uint8_t c1, c2; volatile uint16_t *flags; if (s1 == s2 || limit == 0) return (0); flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags; do { if (s1 == NULL) { c1 = '\0'; } else { c1 = dtrace_load8((uintptr_t)s1++); } if (s2 == NULL) { c2 = '\0'; } else { c2 = dtrace_load8((uintptr_t)s2++); } if (c1 != c2) return (c1 - c2); } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT)); return (0); } /* * Compute strlen(s) for a string using safe memory accesses. The additional * len parameter is used to specify a maximum length to ensure completion. */ static size_t dtrace_strlen(const char *s, size_t lim) { uint_t len; for (len = 0; len != lim; len++) { if (dtrace_load8((uintptr_t)s++) == '\0') break; } return (len); } /* * Check if an address falls within a toxic region. */ static int dtrace_istoxic(uintptr_t kaddr, size_t size) { uintptr_t taddr, tsize; int i; for (i = 0; i < dtrace_toxranges; i++) { taddr = dtrace_toxrange[i].dtt_base; tsize = dtrace_toxrange[i].dtt_limit - taddr; if (kaddr - taddr < tsize) { DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); cpu_core[CPU->cpu_id].cpuc_dtrace_illval = kaddr; return (1); } if (taddr - kaddr < size) { DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); cpu_core[CPU->cpu_id].cpuc_dtrace_illval = taddr; return (1); } } return (0); } /* * Copy src to dst using safe memory accesses. The src is assumed to be unsafe * memory specified by the DIF program. The dst is assumed to be safe memory * that we can store to directly because it is managed by DTrace. As with * standard bcopy, overlapping copies are handled properly. */ static void dtrace_bcopy(const void *src, void *dst, size_t len) { if (len != 0) { uint8_t *s1 = dst; const uint8_t *s2 = src; if (s1 <= s2) { do { *s1++ = dtrace_load8((uintptr_t)s2++); } while (--len != 0); } else { s2 += len; s1 += len; do { *--s1 = dtrace_load8((uintptr_t)--s2); } while (--len != 0); } } } /* * Copy src to dst using safe memory accesses, up to either the specified * length, or the point that a nul byte is encountered. The src is assumed to * be unsafe memory specified by the DIF program. The dst is assumed to be * safe memory that we can store to directly because it is managed by DTrace. * Unlike dtrace_bcopy(), overlapping regions are not handled. */ static void dtrace_strcpy(const void *src, void *dst, size_t len) { if (len != 0) { uint8_t *s1 = dst, c; const uint8_t *s2 = src; do { *s1++ = c = dtrace_load8((uintptr_t)s2++); } while (--len != 0 && c != '\0'); } } /* * Copy src to dst, deriving the size and type from the specified (BYREF) * variable type. The src is assumed to be unsafe memory specified by the DIF * program. The dst is assumed to be DTrace variable memory that is of the * specified type; we assume that we can store to directly. */ static void dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type) { ASSERT(type->dtdt_flags & DIF_TF_BYREF); if (type->dtdt_kind == DIF_TYPE_STRING) { dtrace_strcpy(src, dst, type->dtdt_size); } else { dtrace_bcopy(src, dst, type->dtdt_size); } } /* * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be * unsafe memory specified by the DIF program. The s2 data is assumed to be * safe memory that we can access directly because it is managed by DTrace. */ static int dtrace_bcmp(const void *s1, const void *s2, size_t len) { volatile uint16_t *flags; flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags; if (s1 == s2) return (0); if (s1 == NULL || s2 == NULL) return (1); if (s1 != s2 && len != 0) { const uint8_t *ps1 = s1; const uint8_t *ps2 = s2; do { if (dtrace_load8((uintptr_t)ps1++) != *ps2++) return (1); } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT)); } return (0); } /* * Zero the specified region using a simple byte-by-byte loop. Note that this * is for safe DTrace-managed memory only. */ static void dtrace_bzero(void *dst, size_t len) { uchar_t *cp; for (cp = dst; len != 0; len--) *cp++ = 0; } static void dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum) { uint64_t result[2]; result[0] = addend1[0] + addend2[0]; result[1] = addend1[1] + addend2[1] + (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0); sum[0] = result[0]; sum[1] = result[1]; } /* * Shift the 128-bit value in a by b. If b is positive, shift left. * If b is negative, shift right. */ static void dtrace_shift_128(uint64_t *a, int b) { uint64_t mask; if (b == 0) return; if (b < 0) { b = -b; if (b >= 64) { a[0] = a[1] >> (b - 64); a[1] = 0; } else { a[0] >>= b; mask = 1LL << (64 - b); mask -= 1; a[0] |= ((a[1] & mask) << (64 - b)); a[1] >>= b; } } else { if (b >= 64) { a[1] = a[0] << (b - 64); a[0] = 0; } else { a[1] <<= b; mask = a[0] >> (64 - b); a[1] |= mask; a[0] <<= b; } } } /* * The basic idea is to break the 2 64-bit values into 4 32-bit values, * use native multiplication on those, and then re-combine into the * resulting 128-bit value. * * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) = * hi1 * hi2 << 64 + * hi1 * lo2 << 32 + * hi2 * lo1 << 32 + * lo1 * lo2 */ static void dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product) { uint64_t hi1, hi2, lo1, lo2; uint64_t tmp[2]; hi1 = factor1 >> 32; hi2 = factor2 >> 32; lo1 = factor1 & DT_MASK_LO; lo2 = factor2 & DT_MASK_LO; product[0] = lo1 * lo2; product[1] = hi1 * hi2; tmp[0] = hi1 * lo2; tmp[1] = 0; dtrace_shift_128(tmp, 32); dtrace_add_128(product, tmp, product); tmp[0] = hi2 * lo1; tmp[1] = 0; dtrace_shift_128(tmp, 32); dtrace_add_128(product, tmp, product); } /* * This privilege check should be used by actions and subroutines to * verify that the user credentials of the process that enabled the * invoking ECB match the target credentials */ static int dtrace_priv_proc_common_user(dtrace_state_t *state) { cred_t *cr, *s_cr = state->dts_cred.dcr_cred; /* * We should always have a non-NULL state cred here, since if cred * is null (anonymous tracing), we fast-path bypass this routine. */ ASSERT(s_cr != NULL); if ((cr = dtrace_CRED()) != NULL && posix_cred_get(s_cr)->cr_uid == posix_cred_get(cr)->cr_uid && posix_cred_get(s_cr)->cr_uid == posix_cred_get(cr)->cr_ruid && posix_cred_get(s_cr)->cr_uid == posix_cred_get(cr)->cr_suid && posix_cred_get(s_cr)->cr_gid == posix_cred_get(cr)->cr_gid && posix_cred_get(s_cr)->cr_gid == posix_cred_get(cr)->cr_rgid && posix_cred_get(s_cr)->cr_gid == posix_cred_get(cr)->cr_sgid) return (1); return (0); } /* * This privilege check should be used by actions and subroutines to * verify that the zone of the process that enabled the invoking ECB * matches the target credentials */ static int dtrace_priv_proc_common_zone(dtrace_state_t *state) { cred_t *cr, *s_cr = state->dts_cred.dcr_cred; #pragma unused(cr, s_cr, state) /* __APPLE__ */ /* * We should always have a non-NULL state cred here, since if cred * is null (anonymous tracing), we fast-path bypass this routine. */ ASSERT(s_cr != NULL); return 1; /* APPLE NOTE: Darwin doesn't do zones. */ } /* * This privilege check should be used by actions and subroutines to * verify that the process has not setuid or changed credentials. */ static int dtrace_priv_proc_common_nocd(void) { return 1; /* Darwin omits "No Core Dump" flag. */ } static int dtrace_priv_proc_destructive(dtrace_state_t *state) { int action = state->dts_cred.dcr_action; if (ISSET(current_proc()->p_lflag, P_LNOATTACH)) goto bad; if (dtrace_is_restricted() && !dtrace_can_attach_to_proc(current_proc())) goto bad; if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) && dtrace_priv_proc_common_zone(state) == 0) goto bad; if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) && dtrace_priv_proc_common_user(state) == 0) goto bad; if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) && dtrace_priv_proc_common_nocd() == 0) goto bad; return (1); bad: cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; return (0); } static int dtrace_priv_proc_control(dtrace_state_t *state) { if (ISSET(current_proc()->p_lflag, P_LNOATTACH)) goto bad; if (dtrace_is_restricted() && !dtrace_can_attach_to_proc(current_proc())) goto bad; if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL) return (1); if (dtrace_priv_proc_common_zone(state) && dtrace_priv_proc_common_user(state) && dtrace_priv_proc_common_nocd()) return (1); bad: cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; return (0); } static int dtrace_priv_proc(dtrace_state_t *state) { if (ISSET(current_proc()->p_lflag, P_LNOATTACH)) goto bad; if (dtrace_is_restricted() && !dtrace_can_attach_to_proc(current_proc())) goto bad; if (state->dts_cred.dcr_action & DTRACE_CRA_PROC) return (1); bad: cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; return (0); } /* * The P_LNOATTACH check is an Apple specific check. * We need a version of dtrace_priv_proc() that omits * that check for PID and EXECNAME accesses */ static int dtrace_priv_proc_relaxed(dtrace_state_t *state) { if (state->dts_cred.dcr_action & DTRACE_CRA_PROC) return (1); cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV; return (0); } static int dtrace_priv_kernel(dtrace_state_t *state) { if (dtrace_is_restricted()) goto bad; if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL) return (1); bad: cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV; return (0); } static int dtrace_priv_kernel_destructive(dtrace_state_t *state) { if (dtrace_is_restricted()) goto bad; if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE) return (1); bad: cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV; return (0); } /* * Note: not called from probe context. This function is called * asynchronously (and at a regular interval) from outside of probe context to * clean the dirty dynamic variable lists on all CPUs. Dynamic variable * cleaning is explained in detail in . */ static void dtrace_dynvar_clean(dtrace_dstate_t *dstate) { dtrace_dynvar_t *dirty; dtrace_dstate_percpu_t *dcpu; int i, work = 0; for (i = 0; i < (int)NCPU; i++) { dcpu = &dstate->dtds_percpu[i]; ASSERT(dcpu->dtdsc_rinsing == NULL); /* * If the dirty list is NULL, there is no dirty work to do. */ if (dcpu->dtdsc_dirty == NULL) continue; /* * If the clean list is non-NULL, then we're not going to do * any work for this CPU -- it means that there has not been * a dtrace_dynvar() allocation on this CPU (or from this CPU) * since the last time we cleaned house. */ if (dcpu->dtdsc_clean != NULL) continue; work = 1; /* * Atomically move the dirty list aside. */ do { dirty = dcpu->dtdsc_dirty; /* * Before we zap the dirty list, set the rinsing list. * (This allows for a potential assertion in * dtrace_dynvar(): if a free dynamic variable appears * on a hash chain, either the dirty list or the * rinsing list for some CPU must be non-NULL.) */ dcpu->dtdsc_rinsing = dirty; dtrace_membar_producer(); } while (dtrace_casptr(&dcpu->dtdsc_dirty, dirty, NULL) != dirty); } if (!work) { /* * We have no work to do; we can simply return. */ return; } dtrace_sync(); for (i = 0; i < (int)NCPU; i++) { dcpu = &dstate->dtds_percpu[i]; if (dcpu->dtdsc_rinsing == NULL) continue; /* * We are now guaranteed that no hash chain contains a pointer * into this dirty list; we can make it clean. */ ASSERT(dcpu->dtdsc_clean == NULL); dcpu->dtdsc_clean = dcpu->dtdsc_rinsing; dcpu->dtdsc_rinsing = NULL; } /* * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make * sure that all CPUs have seen all of the dtdsc_clean pointers. * This prevents a race whereby a CPU incorrectly decides that * the state should be something other than DTRACE_DSTATE_CLEAN * after dtrace_dynvar_clean() has completed. */ dtrace_sync(); dstate->dtds_state = DTRACE_DSTATE_CLEAN; } /* * Depending on the value of the op parameter, this function looks-up, * allocates or deallocates an arbitrarily-keyed dynamic variable. If an * allocation is requested, this function will return a pointer to a * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no * variable can be allocated. If NULL is returned, the appropriate counter * will be incremented. */ static dtrace_dynvar_t * dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys, dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate) { uint64_t hashval = DTRACE_DYNHASH_VALID; dtrace_dynhash_t *hash = dstate->dtds_hash; dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL; processorid_t me = CPU->cpu_id, cpu = me; dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me]; size_t bucket, ksize; size_t chunksize = dstate->dtds_chunksize; uintptr_t kdata, lock, nstate; uint_t i; ASSERT(nkeys != 0); /* * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time" * algorithm. For the by-value portions, we perform the algorithm in * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a * bit, and seems to have only a minute effect on distribution. For * the by-reference data, we perform "One-at-a-time" iterating (safely) * over each referenced byte. It's painful to do this, but it's much * better than pathological hash distribution. The efficacy of the * hashing algorithm (and a comparison with other algorithms) may be * found by running the ::dtrace_dynstat MDB dcmd. */ for (i = 0; i < nkeys; i++) { if (key[i].dttk_size == 0) { uint64_t val = key[i].dttk_value; hashval += (val >> 48) & 0xffff; hashval += (hashval << 10); hashval ^= (hashval >> 6); hashval += (val >> 32) & 0xffff; hashval += (hashval << 10); hashval ^= (hashval >> 6); hashval += (val >> 16) & 0xffff; hashval += (hashval << 10); hashval ^= (hashval >> 6); hashval += val & 0xffff; hashval += (hashval << 10); hashval ^= (hashval >> 6); } else { /* * This is incredibly painful, but it beats the hell * out of the alternative. */ uint64_t j, size = key[i].dttk_size; uintptr_t base = (uintptr_t)key[i].dttk_value; if (!dtrace_canload(base, size, mstate, vstate)) break; for (j = 0; j < size; j++) { hashval += dtrace_load8(base + j); hashval += (hashval << 10); hashval ^= (hashval >> 6); } } } if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT)) return (NULL); hashval += (hashval << 3); hashval ^= (hashval >> 11); hashval += (hashval << 15); /* * There is a remote chance (ideally, 1 in 2^31) that our hashval * comes out to be one of our two sentinel hash values. If this * actually happens, we set the hashval to be a value known to be a * non-sentinel value. */ if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK) hashval = DTRACE_DYNHASH_VALID; /* * Yes, it's painful to do a divide here. If the cycle count becomes * important here, tricks can be pulled to reduce it. (However, it's * critical that hash collisions be kept to an absolute minimum; * they're much more painful than a divide.) It's better to have a * solution that generates few collisions and still keeps things * relatively simple. */ bucket = hashval % dstate->dtds_hashsize; if (op == DTRACE_DYNVAR_DEALLOC) { volatile uintptr_t *lockp = &hash[bucket].dtdh_lock; for (;;) { while ((lock = *lockp) & 1) continue; if (dtrace_casptr((void *)(uintptr_t)lockp, (void *)lock, (void *)(lock + 1)) == (void *)lock) break; } dtrace_membar_producer(); } top: prev = NULL; lock = hash[bucket].dtdh_lock; dtrace_membar_consumer(); start = hash[bucket].dtdh_chain; ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK || start->dtdv_hashval != DTRACE_DYNHASH_FREE || op != DTRACE_DYNVAR_DEALLOC)); for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) { dtrace_tuple_t *dtuple = &dvar->dtdv_tuple; dtrace_key_t *dkey = &dtuple->dtt_key[0]; if (dvar->dtdv_hashval != hashval) { if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) { /* * We've reached the sink, and therefore the * end of the hash chain; we can kick out of * the loop knowing that we have seen a valid * snapshot of state. */ ASSERT(dvar->dtdv_next == NULL); ASSERT(dvar == &dtrace_dynhash_sink); break; } if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) { /* * We've gone off the rails: somewhere along * the line, one of the members of this hash * chain was deleted. Note that we could also * detect this by simply letting this loop run * to completion, as we would eventually hit * the end of the dirty list. However, we * want to avoid running the length of the * dirty list unnecessarily (it might be quite * long), so we catch this as early as * possible by detecting the hash marker. In * this case, we simply set dvar to NULL and * break; the conditional after the loop will * send us back to top. */ dvar = NULL; break; } goto next; } if (dtuple->dtt_nkeys != nkeys) goto next; for (i = 0; i < nkeys; i++, dkey++) { if (dkey->dttk_size != key[i].dttk_size) goto next; /* size or type mismatch */ if (dkey->dttk_size != 0) { if (dtrace_bcmp( (void *)(uintptr_t)key[i].dttk_value, (void *)(uintptr_t)dkey->dttk_value, dkey->dttk_size)) goto next; } else { if (dkey->dttk_value != key[i].dttk_value) goto next; } } if (op != DTRACE_DYNVAR_DEALLOC) return (dvar); ASSERT(dvar->dtdv_next == NULL || dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE); if (prev != NULL) { ASSERT(hash[bucket].dtdh_chain != dvar); ASSERT(start != dvar); ASSERT(prev->dtdv_next == dvar); prev->dtdv_next = dvar->dtdv_next; } else { if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar->dtdv_next) != start) { /* * We have failed to atomically swing the * hash table head pointer, presumably because * of a conflicting allocation on another CPU. * We need to reread the hash chain and try * again. */ goto top; } } dtrace_membar_producer(); /* * Now set the hash value to indicate that it's free. */ ASSERT(hash[bucket].dtdh_chain != dvar); dvar->dtdv_hashval = DTRACE_DYNHASH_FREE; dtrace_membar_producer(); /* * Set the next pointer to point at the dirty list, and * atomically swing the dirty pointer to the newly freed dvar. */ do { next = dcpu->dtdsc_dirty; dvar->dtdv_next = next; } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next); /* * Finally, unlock this hash bucket. */ ASSERT(hash[bucket].dtdh_lock == lock); ASSERT(lock & 1); hash[bucket].dtdh_lock++; return (NULL); next: prev = dvar; continue; } if (dvar == NULL) { /* * If dvar is NULL, it is because we went off the rails: * one of the elements that we traversed in the hash chain * was deleted while we were traversing it. In this case, * we assert that we aren't doing a dealloc (deallocs lock * the hash bucket to prevent themselves from racing with * one another), and retry the hash chain traversal. */ ASSERT(op != DTRACE_DYNVAR_DEALLOC); goto top; } if (op != DTRACE_DYNVAR_ALLOC) { /* * If we are not to allocate a new variable, we want to * return NULL now. Before we return, check that the value * of the lock word hasn't changed. If it has, we may have * seen an inconsistent snapshot. */ if (op == DTRACE_DYNVAR_NOALLOC) { if (hash[bucket].dtdh_lock != lock) goto top; } else { ASSERT(op == DTRACE_DYNVAR_DEALLOC); ASSERT(hash[bucket].dtdh_lock == lock); ASSERT(lock & 1); hash[bucket].dtdh_lock++; } return (NULL); } /* * We need to allocate a new dynamic variable. The size we need is the * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the * size of any auxiliary key data (rounded up to 8-byte alignment) plus * the size of any referred-to data (dsize). We then round the final * size up to the chunksize for allocation. */ for (ksize = 0, i = 0; i < nkeys; i++) ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t)); /* * This should be pretty much impossible, but could happen if, say, * strange DIF specified the tuple. Ideally, this should be an * assertion and not an error condition -- but that requires that the * chunksize calculation in dtrace_difo_chunksize() be absolutely * bullet-proof. (That is, it must not be able to be fooled by * malicious DIF.) Given the lack of backwards branches in DIF, * solving this would presumably not amount to solving the Halting * Problem -- but it still seems awfully hard. */ if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) + ksize + dsize > chunksize) { dcpu->dtdsc_drops++; return (NULL); } nstate = DTRACE_DSTATE_EMPTY; do { retry: free = dcpu->dtdsc_free; if (free == NULL) { dtrace_dynvar_t *clean = dcpu->dtdsc_clean; void *rval; if (clean == NULL) { /* * We're out of dynamic variable space on * this CPU. Unless we have tried all CPUs, * we'll try to allocate from a different * CPU. */ switch (dstate->dtds_state) { case DTRACE_DSTATE_CLEAN: { void *sp = &dstate->dtds_state; if (++cpu >= (int)NCPU) cpu = 0; if (dcpu->dtdsc_dirty != NULL && nstate == DTRACE_DSTATE_EMPTY) nstate = DTRACE_DSTATE_DIRTY; if (dcpu->dtdsc_rinsing != NULL) nstate = DTRACE_DSTATE_RINSING; dcpu = &dstate->dtds_percpu[cpu]; if (cpu != me) goto retry; (void) dtrace_cas32(sp, DTRACE_DSTATE_CLEAN, nstate); /* * To increment the correct bean * counter, take another lap. */ goto retry; } case DTRACE_DSTATE_DIRTY: dcpu->dtdsc_dirty_drops++; break; case DTRACE_DSTATE_RINSING: dcpu->dtdsc_rinsing_drops++; break; case DTRACE_DSTATE_EMPTY: dcpu->dtdsc_drops++; break; } DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP); return (NULL); } /* * The clean list appears to be non-empty. We want to * move the clean list to the free list; we start by * moving the clean pointer aside. */ if (dtrace_casptr(&dcpu->dtdsc_clean, clean, NULL) != clean) { /* * We are in one of two situations: * * (a) The clean list was switched to the * free list by another CPU. * * (b) The clean list was added to by the * cleansing cyclic. * * In either of these situations, we can * just reattempt the free list allocation. */ goto retry; } ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE); /* * Now we'll move the clean list to the free list. * It's impossible for this to fail: the only way * the free list can be updated is through this * code path, and only one CPU can own the clean list. * Thus, it would only be possible for this to fail if * this code were racing with dtrace_dynvar_clean(). * (That is, if dtrace_dynvar_clean() updated the clean * list, and we ended up racing to update the free * list.) This race is prevented by the dtrace_sync() * in dtrace_dynvar_clean() -- which flushes the * owners of the clean lists out before resetting * the clean lists. */ rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean); ASSERT(rval == NULL); goto retry; } dvar = free; new_free = dvar->dtdv_next; } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free); /* * We have now allocated a new chunk. We copy the tuple keys into the * tuple array and copy any referenced key data into the data space * following the tuple array. As we do this, we relocate dttk_value * in the final tuple to point to the key data address in the chunk. */ kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys]; dvar->dtdv_data = (void *)(kdata + ksize); dvar->dtdv_tuple.dtt_nkeys = nkeys; for (i = 0; i < nkeys; i++) { dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i]; size_t kesize = key[i].dttk_size; if (kesize != 0) { dtrace_bcopy( (const void *)(uintptr_t)key[i].dttk_value, (void *)kdata, kesize); dkey->dttk_value = kdata; kdata += P2ROUNDUP(kesize, sizeof (uint64_t)); } else { dkey->dttk_value = key[i].dttk_value; } dkey->dttk_size = kesize; } ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE); dvar->dtdv_hashval = hashval; dvar->dtdv_next = start; if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start) return (dvar); /* * The cas has failed. Either another CPU is adding an element to * this hash chain, or another CPU is deleting an element from this * hash chain. The simplest way to deal with both of these cases * (though not necessarily the most efficient) is to free our * allocated block and tail-call ourselves. Note that the free is * to the dirty list and _not_ to the free list. This is to prevent * races with allocators, above. */ dvar->dtdv_hashval = DTRACE_DYNHASH_FREE; dtrace_membar_producer(); do { free = dcpu->dtdsc_dirty; dvar->dtdv_next = free; } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free); return (dtrace_dynvar(dstate, nkeys, key, dsize, op, mstate, vstate)); } /*ARGSUSED*/ static void dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg) { #pragma unused(arg) /* __APPLE__ */ if ((int64_t)nval < (int64_t)*oval) *oval = nval; } /*ARGSUSED*/ static void dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg) { #pragma unused(arg) /* __APPLE__ */ if ((int64_t)nval > (int64_t)*oval) *oval = nval; } static void dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr) { int i, zero = DTRACE_QUANTIZE_ZEROBUCKET; int64_t val = (int64_t)nval; if (val < 0) { for (i = 0; i < zero; i++) { if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) { quanta[i] += incr; return; } } } else { for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) { if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) { quanta[i - 1] += incr; return; } } quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr; return; } ASSERT(0); } static void dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr) { uint64_t arg = *lquanta++; int32_t base = DTRACE_LQUANTIZE_BASE(arg); uint16_t step = DTRACE_LQUANTIZE_STEP(arg); uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg); int32_t val = (int32_t)nval, level; ASSERT(step != 0); ASSERT(levels != 0); if (val < base) { /* * This is an underflow. */ lquanta[0] += incr; return; } level = (val - base) / step; if (level < levels) { lquanta[level + 1] += incr; return; } /* * This is an overflow. */ lquanta[levels + 1] += incr; } static int dtrace_aggregate_llquantize_bucket(int16_t factor, int16_t low, int16_t high, int16_t nsteps, int64_t value) { int64_t this = 1, last, next; int base = 1, order; for (order = 0; order < low; ++order) this *= factor; /* * If our value is less than our factor taken to the power of the * low order of magnitude, it goes into the zeroth bucket. */ if (value < this) return 0; else last = this; for (this *= factor; order <= high; ++order) { int nbuckets = this > nsteps ? nsteps : this; /* * We should not generally get log/linear quantizations * with a high magnitude that allows 64-bits to * overflow, but we nonetheless protect against this * by explicitly checking for overflow, and clamping * our value accordingly. */ next = this * factor; if (next < this) { value = this - 1; } /* * If our value lies within this order of magnitude, * determine its position by taking the offset within * the order of magnitude, dividing by the bucket * width, and adding to our (accumulated) base. */ if (value < this) { return (base + (value - last) / (this / nbuckets)); } base += nbuckets - (nbuckets / factor); last = this; this = next; } /* * Our value is greater than or equal to our factor taken to the * power of one plus the high magnitude -- return the top bucket. */ return base; } static void dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr) { uint64_t arg = *llquanta++; uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg); uint16_t low = DTRACE_LLQUANTIZE_LOW(arg); uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg); uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg); llquanta[dtrace_aggregate_llquantize_bucket(factor, low, high, nsteps, nval)] += incr; } /*ARGSUSED*/ static void dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg) { #pragma unused(arg) /* __APPLE__ */ data[0]++; data[1] += nval; } /*ARGSUSED*/ static void dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg) { #pragma unused(arg) /* __APPLE__ */ int64_t snval = (int64_t)nval; uint64_t tmp[2]; data[0]++; data[1] += nval; /* * What we want to say here is: * * data[2] += nval * nval; * * But given that nval is 64-bit, we could easily overflow, so * we do this as 128-bit arithmetic. */ if (snval < 0) snval = -snval; dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp); dtrace_add_128(data + 2, tmp, data + 2); } /*ARGSUSED*/ static void dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg) { #pragma unused(nval, arg) /* __APPLE__ */ *oval = *oval + 1; } /*ARGSUSED*/ static void dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg) { #pragma unused(arg) /* __APPLE__ */ *oval += nval; } /* * Aggregate given the tuple in the principal data buffer, and the aggregating * action denoted by the specified dtrace_aggregation_t. The aggregation * buffer is specified as the buf parameter. This routine does not return * failure; if there is no space in the aggregation buffer, the data will be * dropped, and a corresponding counter incremented. */ static void dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf, intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg) { #pragma unused(arg) dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec; uint32_t i, ndx, size, fsize; uint32_t align = sizeof (uint64_t) - 1; dtrace_aggbuffer_t *agb; dtrace_aggkey_t *key; uint32_t hashval = 0, limit, isstr; caddr_t tomax, data, kdata; dtrace_actkind_t action; dtrace_action_t *act; uintptr_t offs; if (buf == NULL) return; if (!agg->dtag_hasarg) { /* * Currently, only quantize() and lquantize() take additional * arguments, and they have the same semantics: an increment * value that defaults to 1 when not present. If additional * aggregating actions take arguments, the setting of the * default argument value will presumably have to become more * sophisticated... */ arg = 1; } action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION; size = rec->dtrd_offset - agg->dtag_base; fsize = size + rec->dtrd_size; ASSERT(dbuf->dtb_tomax != NULL); data = dbuf->dtb_tomax + offset + agg->dtag_base; if ((tomax = buf->dtb_tomax) == NULL) { dtrace_buffer_drop(buf); return; } /* * The metastructure is always at the bottom of the buffer. */ agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size - sizeof (dtrace_aggbuffer_t)); if (buf->dtb_offset == 0) { /* * We just kludge up approximately 1/8th of the size to be * buckets. If this guess ends up being routinely * off-the-mark, we may need to dynamically readjust this * based on past performance. */ uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t); if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) < (uintptr_t)tomax || hashsize == 0) { /* * We've been given a ludicrously small buffer; * increment our drop count and leave. */ dtrace_buffer_drop(buf); return; } /* * And now, a pathetic attempt to try to get a an odd (or * perchance, a prime) hash size for better hash distribution. */ if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3)) hashsize -= DTRACE_AGGHASHSIZE_SLEW; agb->dtagb_hashsize = hashsize; agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb - agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *)); agb->dtagb_free = (uintptr_t)agb->dtagb_hash; for (i = 0; i < agb->dtagb_hashsize; i++) agb->dtagb_hash[i] = NULL; } ASSERT(agg->dtag_first != NULL); ASSERT(agg->dtag_first->dta_intuple); /* * Calculate the hash value based on the key. Note that we _don't_ * include the aggid in the hashing (but we will store it as part of * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time" * algorithm: a simple, quick algorithm that has no known funnels, and * gets good distribution in practice. The efficacy of the hashing * algorithm (and a comparison with other algorithms) may be found by * running the ::dtrace_aggstat MDB dcmd. */ for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) { i = act->dta_rec.dtrd_offset - agg->dtag_base; limit = i + act->dta_rec.dtrd_size; ASSERT(limit <= size); isstr = DTRACEACT_ISSTRING(act); for (; i < limit; i++) { hashval += data[i]; hashval += (hashval << 10); hashval ^= (hashval >> 6); if (isstr && data[i] == '\0') break; } } hashval += (hashval << 3); hashval ^= (hashval >> 11); hashval += (hashval << 15); /* * Yes, the divide here is expensive -- but it's generally the least * of the performance issues given the amount of data that we iterate * over to compute hash values, compare data, etc. */ ndx = hashval % agb->dtagb_hashsize; for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) { ASSERT((caddr_t)key >= tomax); ASSERT((caddr_t)key < tomax + buf->dtb_size); if (hashval != key->dtak_hashval || key->dtak_size != size) continue; kdata = key->dtak_data; ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size); for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) { i = act->dta_rec.dtrd_offset - agg->dtag_base; limit = i + act->dta_rec.dtrd_size; ASSERT(limit <= size); isstr = DTRACEACT_ISSTRING(act); for (; i < limit; i++) { if (kdata[i] != data[i]) goto next; if (isstr && data[i] == '\0') break; } } if (action != key->dtak_action) { /* * We are aggregating on the same value in the same * aggregation with two different aggregating actions. * (This should have been picked up in the compiler, * so we may be dealing with errant or devious DIF.) * This is an error condition; we indicate as much, * and return. */ DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return; } /* * This is a hit: we need to apply the aggregator to * the value at this key. */ agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg); return; next: continue; } /* * We didn't find it. We need to allocate some zero-filled space, * link it into the hash table appropriately, and apply the aggregator * to the (zero-filled) value. */ offs = buf->dtb_offset; while (offs & (align - 1)) offs += sizeof (uint32_t); /* * If we don't have enough room to both allocate a new key _and_ * its associated data, increment the drop count and return. */ if ((uintptr_t)tomax + offs + fsize > agb->dtagb_free - sizeof (dtrace_aggkey_t)) { dtrace_buffer_drop(buf); return; } /*CONSTCOND*/ ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1))); key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t)); agb->dtagb_free -= sizeof (dtrace_aggkey_t); key->dtak_data = kdata = tomax + offs; buf->dtb_offset = offs + fsize; /* * Now copy the data across. */ *((dtrace_aggid_t *)kdata) = agg->dtag_id; for (i = sizeof (dtrace_aggid_t); i < size; i++) kdata[i] = data[i]; /* * Because strings are not zeroed out by default, we need to iterate * looking for actions that store strings, and we need to explicitly * pad these strings out with zeroes. */ for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) { int nul; if (!DTRACEACT_ISSTRING(act)) continue; i = act->dta_rec.dtrd_offset - agg->dtag_base; limit = i + act->dta_rec.dtrd_size; ASSERT(limit <= size); for (nul = 0; i < limit; i++) { if (nul) { kdata[i] = '\0'; continue; } if (data[i] != '\0') continue; nul = 1; } } for (i = size; i < fsize; i++) kdata[i] = 0; key->dtak_hashval = hashval; key->dtak_size = size; key->dtak_action = action; key->dtak_next = agb->dtagb_hash[ndx]; agb->dtagb_hash[ndx] = key; /* * Finally, apply the aggregator. */ *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial; agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg); } /* * Given consumer state, this routine finds a speculation in the INACTIVE * state and transitions it into the ACTIVE state. If there is no speculation * in the INACTIVE state, 0 is returned. In this case, no error counter is * incremented -- it is up to the caller to take appropriate action. */ static int dtrace_speculation(dtrace_state_t *state) { int i = 0; dtrace_speculation_state_t current; uint32_t *stat = &state->dts_speculations_unavail, count; while (i < state->dts_nspeculations) { dtrace_speculation_t *spec = &state->dts_speculations[i]; current = spec->dtsp_state; if (current != DTRACESPEC_INACTIVE) { if (current == DTRACESPEC_COMMITTINGMANY || current == DTRACESPEC_COMMITTING || current == DTRACESPEC_DISCARDING) stat = &state->dts_speculations_busy; i++; continue; } if (dtrace_cas32((uint32_t *)&spec->dtsp_state, current, DTRACESPEC_ACTIVE) == current) return (i + 1); } /* * We couldn't find a speculation. If we found as much as a single * busy speculation buffer, we'll attribute this failure as "busy" * instead of "unavail". */ do { count = *stat; } while (dtrace_cas32(stat, count, count + 1) != count); return (0); } /* * This routine commits an active speculation. If the specified speculation * is not in a valid state to perform a commit(), this routine will silently do * nothing. The state of the specified speculation is transitioned according * to the state transition diagram outlined in */ static void dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu, dtrace_specid_t which) { dtrace_speculation_t *spec; dtrace_buffer_t *src, *dest; uintptr_t daddr, saddr, dlimit; dtrace_speculation_state_t current, new = DTRACESPEC_INACTIVE; intptr_t offs; if (which == 0) return; if (which > (dtrace_specid_t)state->dts_nspeculations) { cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; return; } spec = &state->dts_speculations[which - 1]; src = &spec->dtsp_buffer[cpu]; dest = &state->dts_buffer[cpu]; do { current = spec->dtsp_state; if (current == DTRACESPEC_COMMITTINGMANY) break; switch (current) { case DTRACESPEC_INACTIVE: case DTRACESPEC_DISCARDING: return; case DTRACESPEC_COMMITTING: /* * This is only possible if we are (a) commit()'ing * without having done a prior speculate() on this CPU * and (b) racing with another commit() on a different * CPU. There's nothing to do -- we just assert that * our offset is 0. */ ASSERT(src->dtb_offset == 0); return; case DTRACESPEC_ACTIVE: new = DTRACESPEC_COMMITTING; break; case DTRACESPEC_ACTIVEONE: /* * This speculation is active on one CPU. If our * buffer offset is non-zero, we know that the one CPU * must be us. Otherwise, we are committing on a * different CPU from the speculate(), and we must * rely on being asynchronously cleaned. */ if (src->dtb_offset != 0) { new = DTRACESPEC_COMMITTING; break; } /*FALLTHROUGH*/ case DTRACESPEC_ACTIVEMANY: new = DTRACESPEC_COMMITTINGMANY; break; default: ASSERT(0); } } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new) != current); /* * We have set the state to indicate that we are committing this * speculation. Now reserve the necessary space in the destination * buffer. */ if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset, sizeof (uint64_t), state, NULL)) < 0) { dtrace_buffer_drop(dest); goto out; } /* * We have the space; copy the buffer across. (Note that this is a * highly subobtimal bcopy(); in the unlikely event that this becomes * a serious performance issue, a high-performance DTrace-specific * bcopy() should obviously be invented.) */ daddr = (uintptr_t)dest->dtb_tomax + offs; dlimit = daddr + src->dtb_offset; saddr = (uintptr_t)src->dtb_tomax; /* * First, the aligned portion. */ while (dlimit - daddr >= sizeof (uint64_t)) { *((uint64_t *)daddr) = *((uint64_t *)saddr); daddr += sizeof (uint64_t); saddr += sizeof (uint64_t); } /* * Now any left-over bit... */ while (dlimit - daddr) *((uint8_t *)daddr++) = *((uint8_t *)saddr++); /* * Finally, commit the reserved space in the destination buffer. */ dest->dtb_offset = offs + src->dtb_offset; out: /* * If we're lucky enough to be the only active CPU on this speculation * buffer, we can just set the state back to DTRACESPEC_INACTIVE. */ if (current == DTRACESPEC_ACTIVE || (current == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) { uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state, DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE); #pragma unused(rval) /* __APPLE__ */ ASSERT(rval == DTRACESPEC_COMMITTING); } src->dtb_offset = 0; src->dtb_xamot_drops += src->dtb_drops; src->dtb_drops = 0; } /* * This routine discards an active speculation. If the specified speculation * is not in a valid state to perform a discard(), this routine will silently * do nothing. The state of the specified speculation is transitioned * according to the state transition diagram outlined in */ static void dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu, dtrace_specid_t which) { dtrace_speculation_t *spec; dtrace_speculation_state_t current, new = DTRACESPEC_INACTIVE; dtrace_buffer_t *buf; if (which == 0) return; if (which > (dtrace_specid_t)state->dts_nspeculations) { cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; return; } spec = &state->dts_speculations[which - 1]; buf = &spec->dtsp_buffer[cpu]; do { current = spec->dtsp_state; switch (current) { case DTRACESPEC_INACTIVE: case DTRACESPEC_COMMITTINGMANY: case DTRACESPEC_COMMITTING: case DTRACESPEC_DISCARDING: return; case DTRACESPEC_ACTIVE: case DTRACESPEC_ACTIVEMANY: new = DTRACESPEC_DISCARDING; break; case DTRACESPEC_ACTIVEONE: if (buf->dtb_offset != 0) { new = DTRACESPEC_INACTIVE; } else { new = DTRACESPEC_DISCARDING; } break; default: ASSERT(0); } } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new) != current); buf->dtb_offset = 0; buf->dtb_drops = 0; } /* * Note: not called from probe context. This function is called * asynchronously from cross call context to clean any speculations that are * in the COMMITTINGMANY or DISCARDING states. These speculations may not be * transitioned back to the INACTIVE state until all CPUs have cleaned the * speculation. */ static void dtrace_speculation_clean_here(dtrace_state_t *state) { dtrace_icookie_t cookie; processorid_t cpu = CPU->cpu_id; dtrace_buffer_t *dest = &state->dts_buffer[cpu]; dtrace_specid_t i; cookie = dtrace_interrupt_disable(); if (dest->dtb_tomax == NULL) { dtrace_interrupt_enable(cookie); return; } for (i = 0; i < (dtrace_specid_t)state->dts_nspeculations; i++) { dtrace_speculation_t *spec = &state->dts_speculations[i]; dtrace_buffer_t *src = &spec->dtsp_buffer[cpu]; if (src->dtb_tomax == NULL) continue; if (spec->dtsp_state == DTRACESPEC_DISCARDING) { src->dtb_offset = 0; continue; } if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY) continue; if (src->dtb_offset == 0) continue; dtrace_speculation_commit(state, cpu, i + 1); } dtrace_interrupt_enable(cookie); } /* * Note: not called from probe context. This function is called * asynchronously (and at a regular interval) to clean any speculations that * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there * is work to be done, it cross calls all CPUs to perform that work; * COMMITMANY and DISCARDING speculations may not be transitioned back to the * INACTIVE state until they have been cleaned by all CPUs. */ static void dtrace_speculation_clean(dtrace_state_t *state) { int work = 0; uint32_t rv; dtrace_specid_t i; for (i = 0; i < (dtrace_specid_t)state->dts_nspeculations; i++) { dtrace_speculation_t *spec = &state->dts_speculations[i]; ASSERT(!spec->dtsp_cleaning); if (spec->dtsp_state != DTRACESPEC_DISCARDING && spec->dtsp_state != DTRACESPEC_COMMITTINGMANY) continue; work++; spec->dtsp_cleaning = 1; } if (!work) return; dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_speculation_clean_here, state); /* * We now know that all CPUs have committed or discarded their * speculation buffers, as appropriate. We can now set the state * to inactive. */ for (i = 0; i < (dtrace_specid_t)state->dts_nspeculations; i++) { dtrace_speculation_t *spec = &state->dts_speculations[i]; dtrace_speculation_state_t current, new; if (!spec->dtsp_cleaning) continue; current = spec->dtsp_state; ASSERT(current == DTRACESPEC_DISCARDING || current == DTRACESPEC_COMMITTINGMANY); new = DTRACESPEC_INACTIVE; rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new); ASSERT(rv == current); spec->dtsp_cleaning = 0; } } /* * Called as part of a speculate() to get the speculative buffer associated * with a given speculation. Returns NULL if the specified speculation is not * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and * the active CPU is not the specified CPU -- the speculation will be * atomically transitioned into the ACTIVEMANY state. */ static dtrace_buffer_t * dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid, dtrace_specid_t which) { dtrace_speculation_t *spec; dtrace_speculation_state_t current, new = DTRACESPEC_INACTIVE; dtrace_buffer_t *buf; if (which == 0) return (NULL); if (which > (dtrace_specid_t)state->dts_nspeculations) { cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP; return (NULL); } spec = &state->dts_speculations[which - 1]; buf = &spec->dtsp_buffer[cpuid]; do { current = spec->dtsp_state; switch (current) { case DTRACESPEC_INACTIVE: case DTRACESPEC_COMMITTINGMANY: case DTRACESPEC_DISCARDING: return (NULL); case DTRACESPEC_COMMITTING: ASSERT(buf->dtb_offset == 0); return (NULL); case DTRACESPEC_ACTIVEONE: /* * This speculation is currently active on one CPU. * Check the offset in the buffer; if it's non-zero, * that CPU must be us (and we leave the state alone). * If it's zero, assume that we're starting on a new * CPU -- and change the state to indicate that the * speculation is active on more than one CPU. */ if (buf->dtb_offset != 0) return (buf); new = DTRACESPEC_ACTIVEMANY; break; case DTRACESPEC_ACTIVEMANY: return (buf); case DTRACESPEC_ACTIVE: new = DTRACESPEC_ACTIVEONE; break; default: ASSERT(0); } } while (dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new) != current); ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY); return (buf); } /* * Return a string. In the event that the user lacks the privilege to access * arbitrary kernel memory, we copy the string out to scratch memory so that we * don't fail access checking. * * dtrace_dif_variable() uses this routine as a helper for various * builtin values such as 'execname' and 'probefunc.' */ static uintptr_t dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state, dtrace_mstate_t *mstate) { uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t ret; size_t strsz; /* * The easy case: this probe is allowed to read all of memory, so * we can just return this as a vanilla pointer. */ if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) return (addr); /* * This is the tougher case: we copy the string in question from * kernel memory into scratch memory and return it that way: this * ensures that we won't trip up when access checking tests the * BYREF return value. */ strsz = dtrace_strlen((char *)addr, size) + 1; if (mstate->dtms_scratch_ptr + strsz > mstate->dtms_scratch_base + mstate->dtms_scratch_size) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); return (0); } dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr, strsz); ret = mstate->dtms_scratch_ptr; mstate->dtms_scratch_ptr += strsz; return (ret); } /* * This function implements the DIF emulator's variable lookups. The emulator * passes a reserved variable identifier and optional built-in array index. */ static uint64_t dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v, uint64_t ndx) { /* * If we're accessing one of the uncached arguments, we'll turn this * into a reference in the args array. */ if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) { ndx = v - DIF_VAR_ARG0; v = DIF_VAR_ARGS; } switch (v) { case DIF_VAR_ARGS: ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS); if (ndx >= sizeof (mstate->dtms_arg) / sizeof (mstate->dtms_arg[0])) { /* * APPLE NOTE: Account for introduction of __dtrace_probe() */ int aframes = mstate->dtms_probe->dtpr_aframes + 3; dtrace_provider_t *pv; uint64_t val; pv = mstate->dtms_probe->dtpr_provider; if (pv->dtpv_pops.dtps_getargval != NULL) val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg, mstate->dtms_probe->dtpr_id, mstate->dtms_probe->dtpr_arg, ndx, aframes); /* Special case access of arg5 as passed to dtrace_probe_error() (which see.) */ else if (mstate->dtms_probe->dtpr_id == dtrace_probeid_error && ndx == 5) { return ((dtrace_state_t *)(uintptr_t)(mstate->dtms_arg[0]))->dts_arg_error_illval; } else val = dtrace_getarg(ndx, aframes); /* * This is regrettably required to keep the compiler * from tail-optimizing the call to dtrace_getarg(). * The condition always evaluates to true, but the * compiler has no way of figuring that out a priori. * (None of this would be necessary if the compiler * could be relied upon to _always_ tail-optimize * the call to dtrace_getarg() -- but it can't.) */ if (mstate->dtms_probe != NULL) return (val); ASSERT(0); } return (mstate->dtms_arg[ndx]); case DIF_VAR_UREGS: { thread_t thread; if (!dtrace_priv_proc(state)) return (0); if ((thread = current_thread()) == NULL) { DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR); cpu_core[CPU->cpu_id].cpuc_dtrace_illval = 0; return (0); } return (dtrace_getreg(find_user_regs(thread), ndx)); } case DIF_VAR_CURTHREAD: if (!dtrace_priv_kernel(state)) return (0); return ((uint64_t)(uintptr_t)current_thread()); case DIF_VAR_TIMESTAMP: if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) { mstate->dtms_timestamp = dtrace_gethrtime(); mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP; } return (mstate->dtms_timestamp); case DIF_VAR_VTIMESTAMP: ASSERT(dtrace_vtime_references != 0); return (dtrace_get_thread_vtime(current_thread())); case DIF_VAR_WALLTIMESTAMP: if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) { mstate->dtms_walltimestamp = dtrace_gethrestime(); mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP; } return (mstate->dtms_walltimestamp); case DIF_VAR_MACHTIMESTAMP: if (!(mstate->dtms_present & DTRACE_MSTATE_MACHTIMESTAMP)) { mstate->dtms_machtimestamp = mach_absolute_time(); mstate->dtms_present |= DTRACE_MSTATE_MACHTIMESTAMP; } return (mstate->dtms_machtimestamp); case DIF_VAR_IPL: if (!dtrace_priv_kernel(state)) return (0); if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) { mstate->dtms_ipl = dtrace_getipl(); mstate->dtms_present |= DTRACE_MSTATE_IPL; } return (mstate->dtms_ipl); case DIF_VAR_EPID: ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID); return (mstate->dtms_epid); case DIF_VAR_ID: ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); return (mstate->dtms_probe->dtpr_id); case DIF_VAR_STACKDEPTH: if (!dtrace_priv_kernel(state)) return (0); if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) { /* * APPLE NOTE: Account for introduction of __dtrace_probe() */ int aframes = mstate->dtms_probe->dtpr_aframes + 3; mstate->dtms_stackdepth = dtrace_getstackdepth(aframes); mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH; } return (mstate->dtms_stackdepth); case DIF_VAR_USTACKDEPTH: if (!dtrace_priv_proc(state)) return (0); if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) { /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) { mstate->dtms_ustackdepth = 0; } else { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); mstate->dtms_ustackdepth = dtrace_getustackdepth(); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); } mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH; } return (mstate->dtms_ustackdepth); case DIF_VAR_CALLER: if (!dtrace_priv_kernel(state)) return (0); if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) { /* * APPLE NOTE: Account for introduction of __dtrace_probe() */ int aframes = mstate->dtms_probe->dtpr_aframes + 3; if (!DTRACE_ANCHORED(mstate->dtms_probe)) { /* * If this is an unanchored probe, we are * required to go through the slow path: * dtrace_caller() only guarantees correct * results for anchored probes. */ pc_t caller[2]; dtrace_getpcstack(caller, 2, aframes, (uint32_t *)(uintptr_t)mstate->dtms_arg[0]); mstate->dtms_caller = caller[1]; } else if ((mstate->dtms_caller = dtrace_caller(aframes)) == (uintptr_t)-1) { /* * We have failed to do this the quick way; * we must resort to the slower approach of * calling dtrace_getpcstack(). */ pc_t caller; dtrace_getpcstack(&caller, 1, aframes, NULL); mstate->dtms_caller = caller; } mstate->dtms_present |= DTRACE_MSTATE_CALLER; } return (mstate->dtms_caller); case DIF_VAR_UCALLER: if (!dtrace_priv_proc(state)) return (0); if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) { uint64_t ustack[3]; /* * dtrace_getupcstack() fills in the first uint64_t * with the current PID. The second uint64_t will * be the program counter at user-level. The third * uint64_t will contain the caller, which is what * we're after. */ ustack[2] = 0; DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); dtrace_getupcstack(ustack, 3); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); mstate->dtms_ucaller = ustack[2]; mstate->dtms_present |= DTRACE_MSTATE_UCALLER; } return (mstate->dtms_ucaller); case DIF_VAR_PROBEPROV: ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); return (dtrace_dif_varstr( (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name, state, mstate)); case DIF_VAR_PROBEMOD: ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); return (dtrace_dif_varstr( (uintptr_t)mstate->dtms_probe->dtpr_mod, state, mstate)); case DIF_VAR_PROBEFUNC: ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); return (dtrace_dif_varstr( (uintptr_t)mstate->dtms_probe->dtpr_func, state, mstate)); case DIF_VAR_PROBENAME: ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE); return (dtrace_dif_varstr( (uintptr_t)mstate->dtms_probe->dtpr_name, state, mstate)); case DIF_VAR_PID: if (!dtrace_priv_proc_relaxed(state)) return (0); /* * Note that we are assuming that an unanchored probe is * always due to a high-level interrupt. (And we're assuming * that there is only a single high level interrupt.) */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) /* Anchored probe that fires while on an interrupt accrues to process 0 */ return 0; return ((uint64_t)dtrace_proc_selfpid()); case DIF_VAR_PPID: if (!dtrace_priv_proc_relaxed(state)) return (0); /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) return (0); return ((uint64_t)dtrace_proc_selfppid()); case DIF_VAR_TID: /* We do not need to check for null current_thread() */ return thread_tid(current_thread()); /* globally unique */ case DIF_VAR_PTHREAD_SELF: if (!dtrace_priv_proc(state)) return (0); /* Not currently supported, but we should be able to delta the dispatchqaddr and dispatchqoffset to get pthread_self */ return 0; case DIF_VAR_DISPATCHQADDR: if (!dtrace_priv_proc(state)) return (0); /* We do not need to check for null current_thread() */ return thread_dispatchqaddr(current_thread()); case DIF_VAR_EXECNAME: { char *xname = (char *)mstate->dtms_scratch_ptr; size_t scratch_size = MAXCOMLEN+1; /* The scratch allocation's lifetime is that of the clause. */ if (!DTRACE_INSCRATCH(mstate, scratch_size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); return 0; } if (!dtrace_priv_proc_relaxed(state)) return (0); mstate->dtms_scratch_ptr += scratch_size; proc_selfname( xname, MAXCOMLEN ); return ((uint64_t)(uintptr_t)xname); } case DIF_VAR_ZONENAME: { /* scratch_size is equal to length('global') + 1 for the null-terminator. */ char *zname = (char *)mstate->dtms_scratch_ptr; size_t scratch_size = 6 + 1; if (!dtrace_priv_proc(state)) return (0); /* The scratch allocation's lifetime is that of the clause. */ if (!DTRACE_INSCRATCH(mstate, scratch_size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); return 0; } mstate->dtms_scratch_ptr += scratch_size; /* The kernel does not provide zonename, it will always return 'global'. */ strlcpy(zname, "global", scratch_size); return ((uint64_t)(uintptr_t)zname); } case DIF_VAR_UID: if (!dtrace_priv_proc_relaxed(state)) return (0); /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) return (0); return ((uint64_t) dtrace_proc_selfruid()); case DIF_VAR_GID: if (!dtrace_priv_proc(state)) return (0); /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) return (0); if (dtrace_CRED() != NULL) /* Credential does not require lazy initialization. */ return ((uint64_t)kauth_getgid()); else { /* proc_lock would be taken under kauth_cred_proc_ref() in kauth_cred_get(). */ DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return -1ULL; } case DIF_VAR_ERRNO: { uthread_t uthread = (uthread_t)get_bsdthread_info(current_thread()); if (!dtrace_priv_proc(state)) return (0); /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU)) return (0); if (uthread) return (uint64_t)uthread->t_dtrace_errno; else { DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return -1ULL; } } default: DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return (0); } } /* * Emulate the execution of DTrace ID subroutines invoked by the call opcode. * Notice that we don't bother validating the proper number of arguments or * their types in the tuple stack. This isn't needed because all argument * interpretation is safe because of our load safety -- the worst that can * happen is that a bogus program can obtain bogus results. */ static void dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs, dtrace_key_t *tupregs, int nargs, dtrace_mstate_t *mstate, dtrace_state_t *state) { volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; volatile uint64_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval; dtrace_vstate_t *vstate = &state->dts_vstate; #if !defined(__APPLE__) union { mutex_impl_t mi; uint64_t mx; } m; union { krwlock_t ri; uintptr_t rw; } r; #else /* FIXME: awaits lock/mutex work */ #endif /* __APPLE__ */ switch (subr) { case DIF_SUBR_RAND: regs[rd] = (dtrace_gethrtime() * 2416 + 374441) % 1771875; break; #if !defined(__APPLE__) case DIF_SUBR_MUTEX_OWNED: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), mstate, vstate)) { regs[rd] = 0; break; } m.mx = dtrace_load64(tupregs[0].dttk_value); if (MUTEX_TYPE_ADAPTIVE(&m.mi)) regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER; else regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock); break; case DIF_SUBR_MUTEX_OWNER: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), mstate, vstate)) { regs[rd] = 0; break; } m.mx = dtrace_load64(tupregs[0].dttk_value); if (MUTEX_TYPE_ADAPTIVE(&m.mi) && MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER) regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi); else regs[rd] = 0; break; case DIF_SUBR_MUTEX_TYPE_ADAPTIVE: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), mstate, vstate)) { regs[rd] = 0; break; } m.mx = dtrace_load64(tupregs[0].dttk_value); regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi); break; case DIF_SUBR_MUTEX_TYPE_SPIN: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t), mstate, vstate)) { regs[rd] = 0; break; } m.mx = dtrace_load64(tupregs[0].dttk_value); regs[rd] = MUTEX_TYPE_SPIN(&m.mi); break; case DIF_SUBR_RW_READ_HELD: { uintptr_t tmp; if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t), mstate, vstate)) { regs[rd] = 0; break; } r.rw = dtrace_loadptr(tupregs[0].dttk_value); regs[rd] = _RW_READ_HELD(&r.ri, tmp); break; } case DIF_SUBR_RW_WRITE_HELD: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t), mstate, vstate)) { regs[rd] = 0; break; } r.rw = dtrace_loadptr(tupregs[0].dttk_value); regs[rd] = _RW_WRITE_HELD(&r.ri); break; case DIF_SUBR_RW_ISWRITER: if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t), mstate, vstate)) { regs[rd] = 0; break; } r.rw = dtrace_loadptr(tupregs[0].dttk_value); regs[rd] = _RW_ISWRITER(&r.ri); break; #else /* FIXME: awaits lock/mutex work */ #endif /* __APPLE__ */ case DIF_SUBR_BCOPY: { /* * We need to be sure that the destination is in the scratch * region -- no other region is allowed. */ uintptr_t src = tupregs[0].dttk_value; uintptr_t dest = tupregs[1].dttk_value; size_t size = tupregs[2].dttk_value; if (!dtrace_inscratch(dest, size, mstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } if (!dtrace_canload(src, size, mstate, vstate)) { regs[rd] = 0; break; } dtrace_bcopy((void *)src, (void *)dest, size); break; } case DIF_SUBR_ALLOCA: case DIF_SUBR_COPYIN: { uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8); uint64_t size = tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value; size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size; /* * This action doesn't require any credential checks since * probes will not activate in user contexts to which the * enabling user does not have permissions. */ /* * Rounding up the user allocation size could have overflowed * a large, bogus allocation (like -1ULL) to 0. */ if (scratch_size < size || !DTRACE_INSCRATCH(mstate, scratch_size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } if (subr == DIF_SUBR_COPYIN) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); if (dtrace_priv_proc(state)) dtrace_copyin(tupregs[0].dttk_value, dest, size, flags); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); } mstate->dtms_scratch_ptr += scratch_size; regs[rd] = dest; break; } case DIF_SUBR_COPYINTO: { uint64_t size = tupregs[1].dttk_value; uintptr_t dest = tupregs[2].dttk_value; /* * This action doesn't require any credential checks since * probes will not activate in user contexts to which the * enabling user does not have permissions. */ if (!dtrace_inscratch(dest, size, mstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); if (dtrace_priv_proc(state)) dtrace_copyin(tupregs[0].dttk_value, dest, size, flags); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); break; } case DIF_SUBR_COPYINSTR: { uintptr_t dest = mstate->dtms_scratch_ptr; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; if (nargs > 1 && tupregs[1].dttk_value < size) size = tupregs[1].dttk_value + 1; /* * This action doesn't require any credential checks since * probes will not activate in user contexts to which the * enabling user does not have permissions. */ if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); if (dtrace_priv_proc(state)) dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); ((char *)dest)[size - 1] = '\0'; mstate->dtms_scratch_ptr += size; regs[rd] = dest; break; } case DIF_SUBR_MSGSIZE: case DIF_SUBR_MSGDSIZE: { /* Darwin does not implement SysV streams messages */ DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); regs[rd] = 0; break; } case DIF_SUBR_PROGENYOF: { pid_t pid = tupregs[0].dttk_value; struct proc *p = current_proc(); int rval = 0, lim = nprocs; while(p && (lim-- > 0)) { pid_t ppid; ppid = (pid_t)dtrace_load32((uintptr_t)&(p->p_pid)); if (*flags & CPU_DTRACE_FAULT) break; if (ppid == pid) { rval = 1; break; } if (ppid == 0) break; /* Can't climb process tree any further. */ p = (struct proc *)dtrace_loadptr((uintptr_t)&(p->p_pptr)); if (*flags & CPU_DTRACE_FAULT) break; } regs[rd] = rval; break; } case DIF_SUBR_SPECULATION: regs[rd] = dtrace_speculation(state); break; case DIF_SUBR_COPYOUT: { uintptr_t kaddr = tupregs[0].dttk_value; user_addr_t uaddr = tupregs[1].dttk_value; uint64_t size = tupregs[2].dttk_value; if (!dtrace_destructive_disallow && dtrace_priv_proc_control(state) && !dtrace_istoxic(kaddr, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); dtrace_copyout(kaddr, uaddr, size, flags); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); } break; } case DIF_SUBR_COPYOUTSTR: { uintptr_t kaddr = tupregs[0].dttk_value; user_addr_t uaddr = tupregs[1].dttk_value; uint64_t size = tupregs[2].dttk_value; if (!dtrace_destructive_disallow && dtrace_priv_proc_control(state) && !dtrace_istoxic(kaddr, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); dtrace_copyoutstr(kaddr, uaddr, size, flags); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); } break; } case DIF_SUBR_STRLEN: { size_t sz; uintptr_t addr = (uintptr_t)tupregs[0].dttk_value; sz = dtrace_strlen((char *)addr, state->dts_options[DTRACEOPT_STRSIZE]); if (!dtrace_canload(addr, sz + 1, mstate, vstate)) { regs[rd] = 0; break; } regs[rd] = sz; break; } case DIF_SUBR_STRCHR: case DIF_SUBR_STRRCHR: { /* * We're going to iterate over the string looking for the * specified character. We will iterate until we have reached * the string length or we have found the character. If this * is DIF_SUBR_STRRCHR, we will look for the last occurrence * of the specified character instead of the first. */ uintptr_t saddr = tupregs[0].dttk_value; uintptr_t addr = tupregs[0].dttk_value; uintptr_t limit = addr + state->dts_options[DTRACEOPT_STRSIZE]; char c, target = (char)tupregs[1].dttk_value; for (regs[rd] = 0; addr < limit; addr++) { if ((c = dtrace_load8(addr)) == target) { regs[rd] = addr; if (subr == DIF_SUBR_STRCHR) break; } if (c == '\0') break; } if (!dtrace_canload(saddr, addr - saddr, mstate, vstate)) { regs[rd] = 0; break; } break; } case DIF_SUBR_STRSTR: case DIF_SUBR_INDEX: case DIF_SUBR_RINDEX: { /* * We're going to iterate over the string looking for the * specified string. We will iterate until we have reached * the string length or we have found the string. (Yes, this * is done in the most naive way possible -- but considering * that the string we're searching for is likely to be * relatively short, the complexity of Rabin-Karp or similar * hardly seems merited.) */ char *addr = (char *)(uintptr_t)tupregs[0].dttk_value; char *substr = (char *)(uintptr_t)tupregs[1].dttk_value; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; size_t len = dtrace_strlen(addr, size); size_t sublen = dtrace_strlen(substr, size); char *limit = addr + len, *orig = addr; int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1; int inc = 1; regs[rd] = notfound; if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) { regs[rd] = 0; break; } if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate, vstate)) { regs[rd] = 0; break; } /* * strstr() and index()/rindex() have similar semantics if * both strings are the empty string: strstr() returns a * pointer to the (empty) string, and index() and rindex() * both return index 0 (regardless of any position argument). */ if (sublen == 0 && len == 0) { if (subr == DIF_SUBR_STRSTR) regs[rd] = (uintptr_t)addr; else regs[rd] = 0; break; } if (subr != DIF_SUBR_STRSTR) { if (subr == DIF_SUBR_RINDEX) { limit = orig - 1; addr += len; inc = -1; } /* * Both index() and rindex() take an optional position * argument that denotes the starting position. */ if (nargs == 3) { int64_t pos = (int64_t)tupregs[2].dttk_value; /* * If the position argument to index() is * negative, Perl implicitly clamps it at * zero. This semantic is a little surprising * given the special meaning of negative * positions to similar Perl functions like * substr(), but it appears to reflect a * notion that index() can start from a * negative index and increment its way up to * the string. Given this notion, Perl's * rindex() is at least self-consistent in * that it implicitly clamps positions greater * than the string length to be the string * length. Where Perl completely loses * coherence, however, is when the specified * substring is the empty string (""). In * this case, even if the position is * negative, rindex() returns 0 -- and even if * the position is greater than the length, * index() returns the string length. These * semantics violate the notion that index() * should never return a value less than the * specified position and that rindex() should * never return a value greater than the * specified position. (One assumes that * these semantics are artifacts of Perl's * implementation and not the results of * deliberate design -- it beggars belief that * even Larry Wall could desire such oddness.) * While in the abstract one would wish for * consistent position semantics across * substr(), index() and rindex() -- or at the * very least self-consistent position * semantics for index() and rindex() -- we * instead opt to keep with the extant Perl * semantics, in all their broken glory. (Do * we have more desire to maintain Perl's * semantics than Perl does? Probably.) */ if (subr == DIF_SUBR_RINDEX) { if (pos < 0) { if (sublen == 0) regs[rd] = 0; break; } if ((size_t)pos > len) pos = len; } else { if (pos < 0) pos = 0; if ((size_t)pos >= len) { if (sublen == 0) regs[rd] = len; break; } } addr = orig + pos; } } for (regs[rd] = notfound; addr != limit; addr += inc) { if (dtrace_strncmp(addr, substr, sublen) == 0) { if (subr != DIF_SUBR_STRSTR) { /* * As D index() and rindex() are * modeled on Perl (and not on awk), * we return a zero-based (and not a * one-based) index. (For you Perl * weenies: no, we're not going to add * $[ -- and shouldn't you be at a con * or something?) */ regs[rd] = (uintptr_t)(addr - orig); break; } ASSERT(subr == DIF_SUBR_STRSTR); regs[rd] = (uintptr_t)addr; break; } } break; } case DIF_SUBR_STRTOK: { uintptr_t addr = tupregs[0].dttk_value; uintptr_t tokaddr = tupregs[1].dttk_value; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t limit, toklimit = tokaddr + size; char *dest = (char *)mstate->dtms_scratch_ptr; uint8_t c='\0', tokmap[32]; /* 256 / 8 */ uint64_t i = 0; /* * Check both the token buffer and (later) the input buffer, * since both could be non-scratch addresses. */ if (!dtrace_strcanload(tokaddr, size, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } if (addr == 0) { /* * If the address specified is NULL, we use our saved * strtok pointer from the mstate. Note that this * means that the saved strtok pointer is _only_ * valid within multiple enablings of the same probe -- * it behaves like an implicit clause-local variable. */ addr = mstate->dtms_strtok; } else { /* * If the user-specified address is non-NULL we must * access check it. This is the only time we have * a chance to do so, since this address may reside * in the string table of this clause-- future calls * (when we fetch addr from mstate->dtms_strtok) * would fail this access check. */ if (!dtrace_strcanload(addr, size, mstate, vstate)) { regs[rd] = 0; break; } } /* * First, zero the token map, and then process the token * string -- setting a bit in the map for every character * found in the token string. */ for (i = 0; i < (int)sizeof (tokmap); i++) tokmap[i] = 0; for (; tokaddr < toklimit; tokaddr++) { if ((c = dtrace_load8(tokaddr)) == '\0') break; ASSERT((c >> 3) < sizeof (tokmap)); tokmap[c >> 3] |= (1 << (c & 0x7)); } for (limit = addr + size; addr < limit; addr++) { /* * We're looking for a character that is _not_ contained * in the token string. */ if ((c = dtrace_load8(addr)) == '\0') break; if (!(tokmap[c >> 3] & (1 << (c & 0x7)))) break; } if (c == '\0') { /* * We reached the end of the string without finding * any character that was not in the token string. * We return NULL in this case, and we set the saved * address to NULL as well. */ regs[rd] = 0; mstate->dtms_strtok = 0; break; } /* * From here on, we're copying into the destination string. */ for (i = 0; addr < limit && i < size - 1; addr++) { if ((c = dtrace_load8(addr)) == '\0') break; if (tokmap[c >> 3] & (1 << (c & 0x7))) break; ASSERT(i < size); dest[i++] = c; } ASSERT(i < size); dest[i] = '\0'; regs[rd] = (uintptr_t)dest; mstate->dtms_scratch_ptr += size; mstate->dtms_strtok = addr; break; } case DIF_SUBR_SUBSTR: { uintptr_t s = tupregs[0].dttk_value; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; char *d = (char *)mstate->dtms_scratch_ptr; int64_t index = (int64_t)tupregs[1].dttk_value; int64_t remaining = (int64_t)tupregs[2].dttk_value; size_t len = dtrace_strlen((char *)s, size); int64_t i = 0; if (!dtrace_canload(s, len + 1, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } if (nargs <= 2) remaining = (int64_t)size; if (index < 0) { index += len; if (index < 0 && index + remaining > 0) { remaining += index; index = 0; } } if ((size_t)index >= len || index < 0) { remaining = 0; } else if (remaining < 0) { remaining += len - index; } else if ((uint64_t)index + (uint64_t)remaining > size) { remaining = size - index; } for (i = 0; i < remaining; i++) { if ((d[i] = dtrace_load8(s + index + i)) == '\0') break; } d[i] = '\0'; mstate->dtms_scratch_ptr += size; regs[rd] = (uintptr_t)d; break; } case DIF_SUBR_GETMAJOR: regs[rd] = (uintptr_t)major( (dev_t)tupregs[0].dttk_value ); break; case DIF_SUBR_GETMINOR: regs[rd] = (uintptr_t)minor( (dev_t)tupregs[0].dttk_value ); break; case DIF_SUBR_DDI_PATHNAME: { /* APPLE NOTE: currently unsupported on Darwin */ DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); regs[rd] = 0; break; } case DIF_SUBR_STRJOIN: { char *d = (char *)mstate->dtms_scratch_ptr; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t s1 = tupregs[0].dttk_value; uintptr_t s2 = tupregs[1].dttk_value; uint64_t i = 0; if (!dtrace_strcanload(s1, size, mstate, vstate) || !dtrace_strcanload(s2, size, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } for (;;) { if (i >= size) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } if ((d[i++] = dtrace_load8(s1++)) == '\0') { i--; break; } } for (;;) { if (i >= size) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } if ((d[i++] = dtrace_load8(s2++)) == '\0') break; } if (i < size) { mstate->dtms_scratch_ptr += i; regs[rd] = (uintptr_t)d; } break; } case DIF_SUBR_LLTOSTR: { int64_t i = (int64_t)tupregs[0].dttk_value; int64_t val = i < 0 ? i * -1 : i; uint64_t size = 22; /* enough room for 2^64 in decimal */ char *end = (char *)mstate->dtms_scratch_ptr + size - 1; if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } for (*end-- = '\0'; val; val /= 10) *end-- = '0' + (val % 10); if (i == 0) *end-- = '0'; if (i < 0) *end-- = '-'; regs[rd] = (uintptr_t)end + 1; mstate->dtms_scratch_ptr += size; break; } case DIF_SUBR_HTONS: case DIF_SUBR_NTOHS: #ifdef _BIG_ENDIAN regs[rd] = (uint16_t)tupregs[0].dttk_value; #else regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value); #endif break; case DIF_SUBR_HTONL: case DIF_SUBR_NTOHL: #ifdef _BIG_ENDIAN regs[rd] = (uint32_t)tupregs[0].dttk_value; #else regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value); #endif break; case DIF_SUBR_HTONLL: case DIF_SUBR_NTOHLL: #ifdef _BIG_ENDIAN regs[rd] = (uint64_t)tupregs[0].dttk_value; #else regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value); #endif break; case DIF_SUBR_DIRNAME: case DIF_SUBR_BASENAME: { char *dest = (char *)mstate->dtms_scratch_ptr; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t src = tupregs[0].dttk_value; int i, j, len = dtrace_strlen((char *)src, size); int lastbase = -1, firstbase = -1, lastdir = -1; int start, end; if (!dtrace_canload(src, len + 1, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } /* * The basename and dirname for a zero-length string is * defined to be "." */ if (len == 0) { len = 1; src = (uintptr_t)"."; } /* * Start from the back of the string, moving back toward the * front until we see a character that isn't a slash. That * character is the last character in the basename. */ for (i = len - 1; i >= 0; i--) { if (dtrace_load8(src + i) != '/') break; } if (i >= 0) lastbase = i; /* * Starting from the last character in the basename, move * towards the front until we find a slash. The character * that we processed immediately before that is the first * character in the basename. */ for (; i >= 0; i--) { if (dtrace_load8(src + i) == '/') break; } if (i >= 0) firstbase = i + 1; /* * Now keep going until we find a non-slash character. That * character is the last character in the dirname. */ for (; i >= 0; i--) { if (dtrace_load8(src + i) != '/') break; } if (i >= 0) lastdir = i; ASSERT(!(lastbase == -1 && firstbase != -1)); ASSERT(!(firstbase == -1 && lastdir != -1)); if (lastbase == -1) { /* * We didn't find a non-slash character. We know that * the length is non-zero, so the whole string must be * slashes. In either the dirname or the basename * case, we return '/'. */ ASSERT(firstbase == -1); firstbase = lastbase = lastdir = 0; } if (firstbase == -1) { /* * The entire string consists only of a basename * component. If we're looking for dirname, we need * to change our string to be just "."; if we're * looking for a basename, we'll just set the first * character of the basename to be 0. */ if (subr == DIF_SUBR_DIRNAME) { ASSERT(lastdir == -1); src = (uintptr_t)"."; lastdir = 0; } else { firstbase = 0; } } if (subr == DIF_SUBR_DIRNAME) { if (lastdir == -1) { /* * We know that we have a slash in the name -- * or lastdir would be set to 0, above. And * because lastdir is -1, we know that this * slash must be the first character. (That * is, the full string must be of the form * "/basename".) In this case, the last * character of the directory name is 0. */ lastdir = 0; } start = 0; end = lastdir; } else { ASSERT(subr == DIF_SUBR_BASENAME); ASSERT(firstbase != -1 && lastbase != -1); start = firstbase; end = lastbase; } for (i = start, j = 0; i <= end && (uint64_t)j < size - 1; i++, j++) dest[j] = dtrace_load8(src + i); dest[j] = '\0'; regs[rd] = (uintptr_t)dest; mstate->dtms_scratch_ptr += size; break; } case DIF_SUBR_CLEANPATH: { char *dest = (char *)mstate->dtms_scratch_ptr, c; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t src = tupregs[0].dttk_value; int i = 0, j = 0; if (!dtrace_strcanload(src, size, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } /* * Move forward, loading each character. */ do { c = dtrace_load8(src + i++); next: if ((uint64_t)(j + 5) >= size) /* 5 = strlen("/..c\0") */ break; if (c != '/') { dest[j++] = c; continue; } c = dtrace_load8(src + i++); if (c == '/') { /* * We have two slashes -- we can just advance * to the next character. */ goto next; } if (c != '.') { /* * This is not "." and it's not ".." -- we can * just store the "/" and this character and * drive on. */ dest[j++] = '/'; dest[j++] = c; continue; } c = dtrace_load8(src + i++); if (c == '/') { /* * This is a "/./" component. We're not going * to store anything in the destination buffer; * we're just going to go to the next component. */ goto next; } if (c != '.') { /* * This is not ".." -- we can just store the * "/." and this character and continue * processing. */ dest[j++] = '/'; dest[j++] = '.'; dest[j++] = c; continue; } c = dtrace_load8(src + i++); if (c != '/' && c != '\0') { /* * This is not ".." -- it's "..[mumble]". * We'll store the "/.." and this character * and continue processing. */ dest[j++] = '/'; dest[j++] = '.'; dest[j++] = '.'; dest[j++] = c; continue; } /* * This is "/../" or "/..\0". We need to back up * our destination pointer until we find a "/". */ i--; while (j != 0 && dest[--j] != '/') continue; if (c == '\0') dest[++j] = '/'; } while (c != '\0'); dest[j] = '\0'; regs[rd] = (uintptr_t)dest; mstate->dtms_scratch_ptr += size; break; } case DIF_SUBR_INET_NTOA: case DIF_SUBR_INET_NTOA6: case DIF_SUBR_INET_NTOP: { size_t size; int af, argi, i; char *base, *end; if (subr == DIF_SUBR_INET_NTOP) { af = (int)tupregs[0].dttk_value; argi = 1; } else { af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6; argi = 0; } if (af == AF_INET) { #if !defined(__APPLE__) ipaddr_t ip4; #else uint32_t ip4; #endif /* __APPLE__ */ uint8_t *ptr8, val; /* * Safely load the IPv4 address. */ #if !defined(__APPLE__) ip4 = dtrace_load32(tupregs[argi].dttk_value); #else dtrace_bcopy( (void *)(uintptr_t)tupregs[argi].dttk_value, (void *)(uintptr_t)&ip4, sizeof (ip4)); #endif /* __APPLE__ */ /* * Check an IPv4 string will fit in scratch. */ #if !defined(__APPLE__) size = INET_ADDRSTRLEN; #else size = MAX_IPv4_STR_LEN; #endif /* __APPLE__ */ if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } base = (char *)mstate->dtms_scratch_ptr; end = (char *)mstate->dtms_scratch_ptr + size - 1; /* * Stringify as a dotted decimal quad. */ *end-- = '\0'; ptr8 = (uint8_t *)&ip4; for (i = 3; i >= 0; i--) { val = ptr8[i]; if (val == 0) { *end-- = '0'; } else { for (; val; val /= 10) { *end-- = '0' + (val % 10); } } if (i > 0) *end-- = '.'; } ASSERT(end + 1 >= base); } else if (af == AF_INET6) { #if defined(__APPLE__) #define _S6_un __u6_addr #define _S6_u8 __u6_addr8 #endif /* __APPLE__ */ struct in6_addr ip6; int firstzero, tryzero, numzero, v6end; uint16_t val; const char digits[] = "0123456789abcdef"; /* * Stringify using RFC 1884 convention 2 - 16 bit * hexadecimal values with a zero-run compression. * Lower case hexadecimal digits are used. * eg, fe80::214:4fff:fe0b:76c8. * The IPv4 embedded form is returned for inet_ntop, * just the IPv4 string is returned for inet_ntoa6. */ /* * Safely load the IPv6 address. */ dtrace_bcopy( (void *)(uintptr_t)tupregs[argi].dttk_value, (void *)(uintptr_t)&ip6, sizeof (struct in6_addr)); /* * Check an IPv6 string will fit in scratch. */ size = INET6_ADDRSTRLEN; if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } base = (char *)mstate->dtms_scratch_ptr; end = (char *)mstate->dtms_scratch_ptr + size - 1; *end-- = '\0'; /* * Find the longest run of 16 bit zero values * for the single allowed zero compression - "::". */ firstzero = -1; tryzero = -1; numzero = 1; for (i = 0; i < (int)sizeof (struct in6_addr); i++) { if (ip6._S6_un._S6_u8[i] == 0 && tryzero == -1 && i % 2 == 0) { tryzero = i; continue; } if (tryzero != -1 && (ip6._S6_un._S6_u8[i] != 0 || i == sizeof (struct in6_addr) - 1)) { if (i - tryzero <= numzero) { tryzero = -1; continue; } firstzero = tryzero; numzero = i - i % 2 - tryzero; tryzero = -1; if (ip6._S6_un._S6_u8[i] == 0 && i == sizeof (struct in6_addr) - 1) numzero += 2; } } ASSERT(firstzero + numzero <= (int)sizeof (struct in6_addr)); /* * Check for an IPv4 embedded address. */ v6end = sizeof (struct in6_addr) - 2; if (IN6_IS_ADDR_V4MAPPED(&ip6) || IN6_IS_ADDR_V4COMPAT(&ip6)) { for (i = sizeof (struct in6_addr) - 1; i >= (int)DTRACE_V4MAPPED_OFFSET; i--) { ASSERT(end >= base); val = ip6._S6_un._S6_u8[i]; if (val == 0) { *end-- = '0'; } else { for (; val; val /= 10) { *end-- = '0' + val % 10; } } if (i > (int)DTRACE_V4MAPPED_OFFSET) *end-- = '.'; } if (subr == DIF_SUBR_INET_NTOA6) goto inetout; /* * Set v6end to skip the IPv4 address that * we have already stringified. */ v6end = 10; } /* * Build the IPv6 string by working through the * address in reverse. */ for (i = v6end; i >= 0; i -= 2) { ASSERT(end >= base); if (i == firstzero + numzero - 2) { *end-- = ':'; *end-- = ':'; i -= numzero - 2; continue; } if (i < 14 && i != firstzero - 2) *end-- = ':'; val = (ip6._S6_un._S6_u8[i] << 8) + ip6._S6_un._S6_u8[i + 1]; if (val == 0) { *end-- = '0'; } else { for (; val; val /= 16) { *end-- = digits[val % 16]; } } } ASSERT(end + 1 >= base); #if defined(__APPLE__) #undef _S6_un #undef _S6_u8 #endif /* __APPLE__ */ } else { /* * The user didn't use AH_INET or AH_INET6. */ DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); regs[rd] = 0; break; } inetout: regs[rd] = (uintptr_t)end + 1; mstate->dtms_scratch_ptr += size; break; } case DIF_SUBR_TOUPPER: case DIF_SUBR_TOLOWER: { uintptr_t src = tupregs[0].dttk_value; char *dest = (char *)mstate->dtms_scratch_ptr; char lower, upper, base, c; uint64_t size = state->dts_options[DTRACEOPT_STRSIZE]; size_t len = dtrace_strlen((char*) src, size); size_t i = 0; lower = (subr == DIF_SUBR_TOUPPER) ? 'a' : 'A'; upper = (subr == DIF_SUBR_TOUPPER) ? 'z' : 'Z'; base = (subr == DIF_SUBR_TOUPPER) ? 'A' : 'a'; if (!dtrace_canload(src, len + 1, mstate, vstate)) { regs[rd] = 0; break; } if (!DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } for (i = 0; i < size - 1; ++i) { if ((c = dtrace_load8(src + i)) == '\0') break; if (c >= lower && c <= upper) c = base + (c - lower); dest[i] = c; } ASSERT(i < size); dest[i] = '\0'; regs[rd] = (uintptr_t) dest; mstate->dtms_scratch_ptr += size; break; } /* * APPLE NOTE: * CoreProfile callback ('core_profile (uint64_t, [uint64_t], [uint64_t] ...)') */ case DIF_SUBR_COREPROFILE: { uint64_t selector = tupregs[0].dttk_value; uint64_t args[DIF_DTR_NREGS-1] = {0ULL}; uint32_t ii; uint32_t count = (uint32_t)nargs; if (count < 1) { regs[rd] = KERN_FAILURE; break; } if(count > DIF_DTR_NREGS) count = DIF_DTR_NREGS; /* copy in any variadic argument list, bounded by DIF_DTR_NREGS */ for(ii = 0; ii < count-1; ii++) { args[ii] = tupregs[ii+1].dttk_value; } kern_return_t ret = chudxnu_dtrace_callback(selector, args, count-1); if(KERN_SUCCESS != ret) { /* error */ } regs[rd] = ret; break; } } } /* * Emulate the execution of DTrace IR instructions specified by the given * DIF object. This function is deliberately void of assertions as all of * the necessary checks are handled by a call to dtrace_difo_validate(). */ static uint64_t dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, dtrace_state_t *state) { const dif_instr_t *text = difo->dtdo_buf; const uint_t textlen = difo->dtdo_len; const char *strtab = difo->dtdo_strtab; const uint64_t *inttab = difo->dtdo_inttab; uint64_t rval = 0; dtrace_statvar_t *svar; dtrace_dstate_t *dstate = &vstate->dtvs_dynvars; dtrace_difv_t *v; volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; volatile uint64_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval; dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */ uint64_t regs[DIF_DIR_NREGS]; uint64_t *tmp; uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0; int64_t cc_r; uint_t pc = 0, id, opc = 0; uint8_t ttop = 0; dif_instr_t instr; uint_t r1, r2, rd; /* * We stash the current DIF object into the machine state: we need it * for subsequent access checking. */ mstate->dtms_difo = difo; regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */ while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) { opc = pc; instr = text[pc++]; r1 = DIF_INSTR_R1(instr); r2 = DIF_INSTR_R2(instr); rd = DIF_INSTR_RD(instr); switch (DIF_INSTR_OP(instr)) { case DIF_OP_OR: regs[rd] = regs[r1] | regs[r2]; break; case DIF_OP_XOR: regs[rd] = regs[r1] ^ regs[r2]; break; case DIF_OP_AND: regs[rd] = regs[r1] & regs[r2]; break; case DIF_OP_SLL: regs[rd] = regs[r1] << regs[r2]; break; case DIF_OP_SRL: regs[rd] = regs[r1] >> regs[r2]; break; case DIF_OP_SUB: regs[rd] = regs[r1] - regs[r2]; break; case DIF_OP_ADD: regs[rd] = regs[r1] + regs[r2]; break; case DIF_OP_MUL: regs[rd] = regs[r1] * regs[r2]; break; case DIF_OP_SDIV: if (regs[r2] == 0) { regs[rd] = 0; *flags |= CPU_DTRACE_DIVZERO; } else { regs[rd] = (int64_t)regs[r1] / (int64_t)regs[r2]; } break; case DIF_OP_UDIV: if (regs[r2] == 0) { regs[rd] = 0; *flags |= CPU_DTRACE_DIVZERO; } else { regs[rd] = regs[r1] / regs[r2]; } break; case DIF_OP_SREM: if (regs[r2] == 0) { regs[rd] = 0; *flags |= CPU_DTRACE_DIVZERO; } else { regs[rd] = (int64_t)regs[r1] % (int64_t)regs[r2]; } break; case DIF_OP_UREM: if (regs[r2] == 0) { regs[rd] = 0; *flags |= CPU_DTRACE_DIVZERO; } else { regs[rd] = regs[r1] % regs[r2]; } break; case DIF_OP_NOT: regs[rd] = ~regs[r1]; break; case DIF_OP_MOV: regs[rd] = regs[r1]; break; case DIF_OP_CMP: cc_r = regs[r1] - regs[r2]; cc_n = cc_r < 0; cc_z = cc_r == 0; cc_v = 0; cc_c = regs[r1] < regs[r2]; break; case DIF_OP_TST: cc_n = cc_v = cc_c = 0; cc_z = regs[r1] == 0; break; case DIF_OP_BA: pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BE: if (cc_z) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BNE: if (cc_z == 0) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BG: if ((cc_z | (cc_n ^ cc_v)) == 0) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BGU: if ((cc_c | cc_z) == 0) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BGE: if ((cc_n ^ cc_v) == 0) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BGEU: if (cc_c == 0) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BL: if (cc_n ^ cc_v) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BLU: if (cc_c) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BLE: if (cc_z | (cc_n ^ cc_v)) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_BLEU: if (cc_c | cc_z) pc = DIF_INSTR_LABEL(instr); break; case DIF_OP_RLDSB: if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDSB: regs[rd] = (int8_t)dtrace_load8(regs[r1]); break; case DIF_OP_RLDSH: if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDSH: regs[rd] = (int16_t)dtrace_load16(regs[r1]); break; case DIF_OP_RLDSW: if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDSW: regs[rd] = (int32_t)dtrace_load32(regs[r1]); break; case DIF_OP_RLDUB: if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDUB: regs[rd] = dtrace_load8(regs[r1]); break; case DIF_OP_RLDUH: if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDUH: regs[rd] = dtrace_load16(regs[r1]); break; case DIF_OP_RLDUW: if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDUW: regs[rd] = dtrace_load32(regs[r1]); break; case DIF_OP_RLDX: if (!dtrace_canstore(regs[r1], 8, mstate, vstate)) { *flags |= CPU_DTRACE_KPRIV; *illval = regs[r1]; break; } /*FALLTHROUGH*/ case DIF_OP_LDX: regs[rd] = dtrace_load64(regs[r1]); break; /* * Darwin 32-bit kernel may fetch from 64-bit user. * Do not cast regs to uintptr_t * DIF_OP_ULDSB,DIF_OP_ULDSH, DIF_OP_ULDSW, DIF_OP_ULDUB * DIF_OP_ULDUH, DIF_OP_ULDUW, DIF_OP_ULDX */ case DIF_OP_ULDSB: regs[rd] = (int8_t) dtrace_fuword8(regs[r1]); break; case DIF_OP_ULDSH: regs[rd] = (int16_t) dtrace_fuword16(regs[r1]); break; case DIF_OP_ULDSW: regs[rd] = (int32_t) dtrace_fuword32(regs[r1]); break; case DIF_OP_ULDUB: regs[rd] = dtrace_fuword8(regs[r1]); break; case DIF_OP_ULDUH: regs[rd] = dtrace_fuword16(regs[r1]); break; case DIF_OP_ULDUW: regs[rd] = dtrace_fuword32(regs[r1]); break; case DIF_OP_ULDX: regs[rd] = dtrace_fuword64(regs[r1]); break; case DIF_OP_RET: rval = regs[rd]; pc = textlen; break; case DIF_OP_NOP: break; case DIF_OP_SETX: regs[rd] = inttab[DIF_INSTR_INTEGER(instr)]; break; case DIF_OP_SETS: regs[rd] = (uint64_t)(uintptr_t) (strtab + DIF_INSTR_STRING(instr)); break; case DIF_OP_SCMP: { size_t sz = state->dts_options[DTRACEOPT_STRSIZE]; uintptr_t s1 = regs[r1]; uintptr_t s2 = regs[r2]; if (s1 != 0 && !dtrace_strcanload(s1, sz, mstate, vstate)) break; if (s2 != 0 && !dtrace_strcanload(s2, sz, mstate, vstate)) break; cc_r = dtrace_strncmp((char *)s1, (char *)s2, sz); cc_n = cc_r < 0; cc_z = cc_r == 0; cc_v = cc_c = 0; break; } case DIF_OP_LDGA: regs[rd] = dtrace_dif_variable(mstate, state, r1, regs[r2]); break; case DIF_OP_LDGS: id = DIF_INSTR_VAR(instr); if (id >= DIF_VAR_OTHER_UBASE) { uintptr_t a; id -= DIF_VAR_OTHER_UBASE; svar = vstate->dtvs_globals[id]; ASSERT(svar != NULL); v = &svar->dtsv_var; if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) { regs[rd] = svar->dtsv_data; break; } a = (uintptr_t)svar->dtsv_data; if (*(uint8_t *)a == UINT8_MAX) { /* * If the 0th byte is set to UINT8_MAX * then this is to be treated as a * reference to a NULL variable. */ regs[rd] = 0; } else { regs[rd] = a + sizeof (uint64_t); } break; } regs[rd] = dtrace_dif_variable(mstate, state, id, 0); break; case DIF_OP_STGS: id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; svar = vstate->dtvs_globals[id]; ASSERT(svar != NULL); v = &svar->dtsv_var; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { uintptr_t a = (uintptr_t)svar->dtsv_data; ASSERT(a != 0); ASSERT(svar->dtsv_size != 0); if (regs[rd] == 0) { *(uint8_t *)a = UINT8_MAX; break; } else { *(uint8_t *)a = 0; a += sizeof (uint64_t); } if (!dtrace_vcanload( (void *)(uintptr_t)regs[rd], &v->dtdv_type, mstate, vstate)) break; dtrace_vcopy((void *)(uintptr_t)regs[rd], (void *)a, &v->dtdv_type); break; } svar->dtsv_data = regs[rd]; break; case DIF_OP_LDTA: /* * There are no DTrace built-in thread-local arrays at * present. This opcode is saved for future work. */ *flags |= CPU_DTRACE_ILLOP; regs[rd] = 0; break; case DIF_OP_LDLS: id = DIF_INSTR_VAR(instr); if (id < DIF_VAR_OTHER_UBASE) { /* * For now, this has no meaning. */ regs[rd] = 0; break; } id -= DIF_VAR_OTHER_UBASE; ASSERT(id < (uint_t)vstate->dtvs_nlocals); ASSERT(vstate->dtvs_locals != NULL); svar = vstate->dtvs_locals[id]; ASSERT(svar != NULL); v = &svar->dtsv_var; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { uintptr_t a = (uintptr_t)svar->dtsv_data; size_t sz = v->dtdv_type.dtdt_size; sz += sizeof (uint64_t); ASSERT(svar->dtsv_size == (int)NCPU * sz); a += CPU->cpu_id * sz; if (*(uint8_t *)a == UINT8_MAX) { /* * If the 0th byte is set to UINT8_MAX * then this is to be treated as a * reference to a NULL variable. */ regs[rd] = 0; } else { regs[rd] = a + sizeof (uint64_t); } break; } ASSERT(svar->dtsv_size == (int)NCPU * sizeof (uint64_t)); tmp = (uint64_t *)(uintptr_t)svar->dtsv_data; regs[rd] = tmp[CPU->cpu_id]; break; case DIF_OP_STLS: id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; ASSERT(id < (uint_t)vstate->dtvs_nlocals); ASSERT(vstate->dtvs_locals != NULL); svar = vstate->dtvs_locals[id]; ASSERT(svar != NULL); v = &svar->dtsv_var; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { uintptr_t a = (uintptr_t)svar->dtsv_data; size_t sz = v->dtdv_type.dtdt_size; sz += sizeof (uint64_t); ASSERT(svar->dtsv_size == (int)NCPU * sz); a += CPU->cpu_id * sz; if (regs[rd] == 0) { *(uint8_t *)a = UINT8_MAX; break; } else { *(uint8_t *)a = 0; a += sizeof (uint64_t); } if (!dtrace_vcanload( (void *)(uintptr_t)regs[rd], &v->dtdv_type, mstate, vstate)) break; dtrace_vcopy((void *)(uintptr_t)regs[rd], (void *)a, &v->dtdv_type); break; } ASSERT(svar->dtsv_size == (int)NCPU * sizeof (uint64_t)); tmp = (uint64_t *)(uintptr_t)svar->dtsv_data; tmp[CPU->cpu_id] = regs[rd]; break; case DIF_OP_LDTS: { dtrace_dynvar_t *dvar; dtrace_key_t *key; id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; v = &vstate->dtvs_tlocals[id]; key = &tupregs[DIF_DTR_NREGS]; key[0].dttk_value = (uint64_t)id; key[0].dttk_size = 0; DTRACE_TLS_THRKEY(key[1].dttk_value); key[1].dttk_size = 0; dvar = dtrace_dynvar(dstate, 2, key, sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC, mstate, vstate); if (dvar == NULL) { regs[rd] = 0; break; } if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data; } else { regs[rd] = *((uint64_t *)dvar->dtdv_data); } break; } case DIF_OP_STTS: { dtrace_dynvar_t *dvar; dtrace_key_t *key; id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; key = &tupregs[DIF_DTR_NREGS]; key[0].dttk_value = (uint64_t)id; key[0].dttk_size = 0; DTRACE_TLS_THRKEY(key[1].dttk_value); key[1].dttk_size = 0; v = &vstate->dtvs_tlocals[id]; dvar = dtrace_dynvar(dstate, 2, key, v->dtdv_type.dtdt_size > sizeof (uint64_t) ? v->dtdv_type.dtdt_size : sizeof (uint64_t), regs[rd] ? DTRACE_DYNVAR_ALLOC : DTRACE_DYNVAR_DEALLOC, mstate, vstate); /* * Given that we're storing to thread-local data, * we need to flush our predicate cache. */ dtrace_set_thread_predcache(current_thread(), 0); if (dvar == NULL) break; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { if (!dtrace_vcanload( (void *)(uintptr_t)regs[rd], &v->dtdv_type, mstate, vstate)) break; dtrace_vcopy((void *)(uintptr_t)regs[rd], dvar->dtdv_data, &v->dtdv_type); } else { *((uint64_t *)dvar->dtdv_data) = regs[rd]; } break; } case DIF_OP_SRA: regs[rd] = (int64_t)regs[r1] >> regs[r2]; break; case DIF_OP_CALL: dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd, regs, tupregs, ttop, mstate, state); break; case DIF_OP_PUSHTR: if (ttop == DIF_DTR_NREGS) { *flags |= CPU_DTRACE_TUPOFLOW; break; } if (r1 == DIF_TYPE_STRING) { /* * If this is a string type and the size is 0, * we'll use the system-wide default string * size. Note that we are _not_ looking at * the value of the DTRACEOPT_STRSIZE option; * had this been set, we would expect to have * a non-zero size value in the "pushtr". */ tupregs[ttop].dttk_size = dtrace_strlen((char *)(uintptr_t)regs[rd], regs[r2] ? regs[r2] : dtrace_strsize_default) + 1; } else { tupregs[ttop].dttk_size = regs[r2]; } tupregs[ttop++].dttk_value = regs[rd]; break; case DIF_OP_PUSHTV: if (ttop == DIF_DTR_NREGS) { *flags |= CPU_DTRACE_TUPOFLOW; break; } tupregs[ttop].dttk_value = regs[rd]; tupregs[ttop++].dttk_size = 0; break; case DIF_OP_POPTS: if (ttop != 0) ttop--; break; case DIF_OP_FLUSHTS: ttop = 0; break; case DIF_OP_LDGAA: case DIF_OP_LDTAA: { dtrace_dynvar_t *dvar; dtrace_key_t *key = tupregs; uint_t nkeys = ttop; id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; key[nkeys].dttk_value = (uint64_t)id; key[nkeys++].dttk_size = 0; if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) { DTRACE_TLS_THRKEY(key[nkeys].dttk_value); key[nkeys++].dttk_size = 0; v = &vstate->dtvs_tlocals[id]; } else { v = &vstate->dtvs_globals[id]->dtsv_var; } dvar = dtrace_dynvar(dstate, nkeys, key, v->dtdv_type.dtdt_size > sizeof (uint64_t) ? v->dtdv_type.dtdt_size : sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC, mstate, vstate); if (dvar == NULL) { regs[rd] = 0; break; } if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data; } else { regs[rd] = *((uint64_t *)dvar->dtdv_data); } break; } case DIF_OP_STGAA: case DIF_OP_STTAA: { dtrace_dynvar_t *dvar; dtrace_key_t *key = tupregs; uint_t nkeys = ttop; id = DIF_INSTR_VAR(instr); ASSERT(id >= DIF_VAR_OTHER_UBASE); id -= DIF_VAR_OTHER_UBASE; key[nkeys].dttk_value = (uint64_t)id; key[nkeys++].dttk_size = 0; if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) { DTRACE_TLS_THRKEY(key[nkeys].dttk_value); key[nkeys++].dttk_size = 0; v = &vstate->dtvs_tlocals[id]; } else { v = &vstate->dtvs_globals[id]->dtsv_var; } dvar = dtrace_dynvar(dstate, nkeys, key, v->dtdv_type.dtdt_size > sizeof (uint64_t) ? v->dtdv_type.dtdt_size : sizeof (uint64_t), regs[rd] ? DTRACE_DYNVAR_ALLOC : DTRACE_DYNVAR_DEALLOC, mstate, vstate); if (dvar == NULL) break; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) { if (!dtrace_vcanload( (void *)(uintptr_t)regs[rd], &v->dtdv_type, mstate, vstate)) break; dtrace_vcopy((void *)(uintptr_t)regs[rd], dvar->dtdv_data, &v->dtdv_type); } else { *((uint64_t *)dvar->dtdv_data) = regs[rd]; } break; } case DIF_OP_ALLOCS: { uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8); size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1]; /* * Rounding up the user allocation size could have * overflowed large, bogus allocations (like -1ULL) to * 0. */ if (size < regs[r1] || !DTRACE_INSCRATCH(mstate, size)) { DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); regs[rd] = 0; break; } dtrace_bzero((void *) mstate->dtms_scratch_ptr, size); mstate->dtms_scratch_ptr += size; regs[rd] = ptr; break; } case DIF_OP_COPYS: if (!dtrace_canstore(regs[rd], regs[r2], mstate, vstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate)) break; dtrace_bcopy((void *)(uintptr_t)regs[r1], (void *)(uintptr_t)regs[rd], (size_t)regs[r2]); break; case DIF_OP_STB: if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1]; break; case DIF_OP_STH: if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } if (regs[rd] & 1) { *flags |= CPU_DTRACE_BADALIGN; *illval = regs[rd]; break; } *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1]; break; case DIF_OP_STW: if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } if (regs[rd] & 3) { *flags |= CPU_DTRACE_BADALIGN; *illval = regs[rd]; break; } *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1]; break; case DIF_OP_STX: if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) { *flags |= CPU_DTRACE_BADADDR; *illval = regs[rd]; break; } /* * Darwin kmem_zalloc() called from * dtrace_difo_init() is 4-byte aligned. */ if (regs[rd] & 3) { *flags |= CPU_DTRACE_BADALIGN; *illval = regs[rd]; break; } *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1]; break; } } if (!(*flags & CPU_DTRACE_FAULT)) return (rval); mstate->dtms_fltoffs = opc * sizeof (dif_instr_t); mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS; return (0); } static void dtrace_action_breakpoint(dtrace_ecb_t *ecb) { dtrace_probe_t *probe = ecb->dte_probe; dtrace_provider_t *prov = probe->dtpr_provider; char c[DTRACE_FULLNAMELEN + 80], *str; const char *msg = "dtrace: breakpoint action at probe "; const char *ecbmsg = " (ecb "; uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4)); uintptr_t val = (uintptr_t)ecb; int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0; if (dtrace_destructive_disallow) return; /* * It's impossible to be taking action on the NULL probe. */ ASSERT(probe != NULL); /* * This is a poor man's (destitute man's?) sprintf(): we want to * print the provider name, module name, function name and name of * the probe, along with the hex address of the ECB with the breakpoint * action -- all of which we must place in the character buffer by * hand. */ while (*msg != '\0') c[i++] = *msg++; for (str = prov->dtpv_name; *str != '\0'; str++) c[i++] = *str; c[i++] = ':'; for (str = probe->dtpr_mod; *str != '\0'; str++) c[i++] = *str; c[i++] = ':'; for (str = probe->dtpr_func; *str != '\0'; str++) c[i++] = *str; c[i++] = ':'; for (str = probe->dtpr_name; *str != '\0'; str++) c[i++] = *str; while (*ecbmsg != '\0') c[i++] = *ecbmsg++; while (shift >= 0) { mask = (uintptr_t)0xf << shift; if (val >= ((uintptr_t)1 << shift)) c[i++] = "0123456789abcdef"[(val & mask) >> shift]; shift -= 4; } c[i++] = ')'; c[i] = '\0'; debug_enter(c); } static void dtrace_action_panic(dtrace_ecb_t *ecb) { dtrace_probe_t *probe = ecb->dte_probe; /* * It's impossible to be taking action on the NULL probe. */ ASSERT(probe != NULL); if (dtrace_destructive_disallow) return; if (dtrace_panicked != NULL) return; if (dtrace_casptr(&dtrace_panicked, NULL, current_thread()) != NULL) return; /* * We won the right to panic. (We want to be sure that only one * thread calls panic() from dtrace_probe(), and that panic() is * called exactly once.) */ panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)", probe->dtpr_provider->dtpv_name, probe->dtpr_mod, probe->dtpr_func, probe->dtpr_name, (void *)ecb); /* * APPLE NOTE: this was for an old Mac OS X debug feature * allowing a return from panic(). Revisit someday. */ dtrace_panicked = NULL; } static void dtrace_action_raise(uint64_t sig) { if (dtrace_destructive_disallow) return; if (sig >= NSIG) { DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return; } /* * raise() has a queue depth of 1 -- we ignore all subsequent * invocations of the raise() action. */ uthread_t uthread = (uthread_t)get_bsdthread_info(current_thread()); if (uthread && uthread->t_dtrace_sig == 0) { uthread->t_dtrace_sig = sig; act_set_astbsd(current_thread()); } } static void dtrace_action_stop(void) { if (dtrace_destructive_disallow) return; uthread_t uthread = (uthread_t)get_bsdthread_info(current_thread()); if (uthread) { /* * The currently running process will be set to task_suspend * when it next leaves the kernel. */ uthread->t_dtrace_stop = 1; act_set_astbsd(current_thread()); } } /* * APPLE NOTE: pidresume works in conjunction with the dtrace stop action. * Both activate only when the currently running process next leaves the * kernel. */ static void dtrace_action_pidresume(uint64_t pid) { if (dtrace_destructive_disallow) return; if (kauth_cred_issuser(kauth_cred_get()) == 0) { DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP); return; } uthread_t uthread = (uthread_t)get_bsdthread_info(current_thread()); /* * When the currently running process leaves the kernel, it attempts to * task_resume the process (denoted by pid), if that pid appears to have * been stopped by dtrace_action_stop(). * The currently running process has a pidresume() queue depth of 1 -- * subsequent invocations of the pidresume() action are ignored. */ if (pid != 0 && uthread && uthread->t_dtrace_resumepid == 0) { uthread->t_dtrace_resumepid = pid; act_set_astbsd(current_thread()); } } static void dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val) { hrtime_t now; volatile uint16_t *flags; dtrace_cpu_t *cpu = CPU; if (dtrace_destructive_disallow) return; flags = (volatile uint16_t *)&cpu_core[cpu->cpu_id].cpuc_dtrace_flags; now = dtrace_gethrtime(); if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) { /* * We need to advance the mark to the current time. */ cpu->cpu_dtrace_chillmark = now; cpu->cpu_dtrace_chilled = 0; } /* * Now check to see if the requested chill time would take us over * the maximum amount of time allowed in the chill interval. (Or * worse, if the calculation itself induces overflow.) */ if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max || cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) { *flags |= CPU_DTRACE_ILLOP; return; } while (dtrace_gethrtime() - now < val) continue; /* * Normally, we assure that the value of the variable "timestamp" does * not change within an ECB. The presence of chill() represents an * exception to this rule, however. */ mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP; cpu->cpu_dtrace_chilled += val; } static void dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t *buf, uint64_t arg) { int nframes = DTRACE_USTACK_NFRAMES(arg); int strsize = DTRACE_USTACK_STRSIZE(arg); uint64_t *pcs = &buf[1], *fps; char *str = (char *)&pcs[nframes]; int size, offs = 0, i, j; uintptr_t old = mstate->dtms_scratch_ptr, saved; uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; char *sym; /* * Should be taking a faster path if string space has not been * allocated. */ ASSERT(strsize != 0); /* * We will first allocate some temporary space for the frame pointers. */ fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8); size = (uintptr_t)fps - mstate->dtms_scratch_ptr + (nframes * sizeof (uint64_t)); if (!DTRACE_INSCRATCH(mstate, (uintptr_t)size)) { /* * Not enough room for our frame pointers -- need to indicate * that we ran out of scratch space. */ DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH); return; } mstate->dtms_scratch_ptr += size; saved = mstate->dtms_scratch_ptr; /* * Now get a stack with both program counters and frame pointers. */ DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); dtrace_getufpstack(buf, fps, nframes + 1); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); /* * If that faulted, we're cooked. */ if (*flags & CPU_DTRACE_FAULT) goto out; /* * Now we want to walk up the stack, calling the USTACK helper. For * each iteration, we restore the scratch pointer. */ for (i = 0; i < nframes; i++) { mstate->dtms_scratch_ptr = saved; if (offs >= strsize) break; sym = (char *)(uintptr_t)dtrace_helper( DTRACE_HELPER_ACTION_USTACK, mstate, state, pcs[i], fps[i]); /* * If we faulted while running the helper, we're going to * clear the fault and null out the corresponding string. */ if (*flags & CPU_DTRACE_FAULT) { *flags &= ~CPU_DTRACE_FAULT; str[offs++] = '\0'; continue; } if (sym == NULL) { str[offs++] = '\0'; continue; } DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); /* * Now copy in the string that the helper returned to us. */ for (j = 0; offs + j < strsize; j++) { if ((str[offs + j] = sym[j]) == '\0') break; } DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); offs += j + 1; } if (offs >= strsize) { /* * If we didn't have room for all of the strings, we don't * abort processing -- this needn't be a fatal error -- but we * still want to increment a counter (dts_stkstroverflows) to * allow this condition to be warned about. (If this is from * a jstack() action, it is easily tuned via jstackstrsize.) */ dtrace_error(&state->dts_stkstroverflows); } while (offs < strsize) str[offs++] = '\0'; out: mstate->dtms_scratch_ptr = old; } /* * If you're looking for the epicenter of DTrace, you just found it. This * is the function called by the provider to fire a probe -- from which all * subsequent probe-context DTrace activity emanates. */ static void __dtrace_probe(dtrace_id_t id, uint64_t arg0, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4) { processorid_t cpuid; dtrace_icookie_t cookie; dtrace_probe_t *probe; dtrace_mstate_t mstate; dtrace_ecb_t *ecb; dtrace_action_t *act; intptr_t offs; size_t size; int vtime, onintr; volatile uint16_t *flags; hrtime_t now; cookie = dtrace_interrupt_disable(); probe = dtrace_probes[id - 1]; cpuid = CPU->cpu_id; onintr = CPU_ON_INTR(CPU); if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE && probe->dtpr_predcache == dtrace_get_thread_predcache(current_thread())) { /* * We have hit in the predicate cache; we know that * this predicate would evaluate to be false. */ dtrace_interrupt_enable(cookie); return; } if (panic_quiesce) { /* * We don't trace anything if we're panicking. */ dtrace_interrupt_enable(cookie); return; } #if !defined(__APPLE__) now = dtrace_gethrtime(); vtime = dtrace_vtime_references != 0; if (vtime && curthread->t_dtrace_start) curthread->t_dtrace_vtime += now - curthread->t_dtrace_start; #else /* * APPLE NOTE: The time spent entering DTrace and arriving * to this point, is attributed to the current thread. * Instead it should accrue to DTrace. FIXME */ vtime = dtrace_vtime_references != 0; if (vtime) { int64_t dtrace_accum_time, recent_vtime; thread_t thread = current_thread(); dtrace_accum_time = dtrace_get_thread_tracing(thread); /* Time spent inside DTrace so far (nanoseconds) */ if (dtrace_accum_time >= 0) { recent_vtime = dtrace_abs_to_nano(dtrace_calc_thread_recent_vtime(thread)); /* up to the moment thread vtime */ recent_vtime = recent_vtime - dtrace_accum_time; /* Time without DTrace contribution */ dtrace_set_thread_vtime(thread, recent_vtime); } } now = dtrace_gethrtime(); /* must not precede dtrace_calc_thread_recent_vtime() call! */ #endif /* __APPLE__ */ /* * APPLE NOTE: A provider may call dtrace_probe_error() in lieu of * dtrace_probe() in some circumstances. See, e.g. fasttrap_isa.c. * However the provider has no access to ECB context, so passes * 0 through "arg0" and the probe_id of the overridden probe as arg1. * Detect that here and cons up a viable state (from the probe_id). */ if (dtrace_probeid_error == id && 0 == arg0) { dtrace_id_t ftp_id = (dtrace_id_t)arg1; dtrace_probe_t *ftp_probe = dtrace_probes[ftp_id - 1]; dtrace_ecb_t *ftp_ecb = ftp_probe->dtpr_ecb; if (NULL != ftp_ecb) { dtrace_state_t *ftp_state = ftp_ecb->dte_state; arg0 = (uint64_t)(uintptr_t)ftp_state; arg1 = ftp_ecb->dte_epid; /* * args[2-4] established by caller. */ ftp_state->dts_arg_error_illval = -1; /* arg5 */ } } mstate.dtms_difo = NULL; mstate.dtms_probe = probe; mstate.dtms_strtok = 0; mstate.dtms_arg[0] = arg0; mstate.dtms_arg[1] = arg1; mstate.dtms_arg[2] = arg2; mstate.dtms_arg[3] = arg3; mstate.dtms_arg[4] = arg4; flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags; for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) { dtrace_predicate_t *pred = ecb->dte_predicate; dtrace_state_t *state = ecb->dte_state; dtrace_buffer_t *buf = &state->dts_buffer[cpuid]; dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid]; dtrace_vstate_t *vstate = &state->dts_vstate; dtrace_provider_t *prov = probe->dtpr_provider; uint64_t tracememsize = 0; int committed = 0; caddr_t tomax; /* * A little subtlety with the following (seemingly innocuous) * declaration of the automatic 'val': by looking at the * code, you might think that it could be declared in the * action processing loop, below. (That is, it's only used in * the action processing loop.) However, it must be declared * out of that scope because in the case of DIF expression * arguments to aggregating actions, one iteration of the * action loop will use the last iteration's value. */ #ifdef lint uint64_t val = 0; #else uint64_t val = 0; #endif mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE; *flags &= ~CPU_DTRACE_ERROR; if (prov == dtrace_provider) { /* * If dtrace itself is the provider of this probe, * we're only going to continue processing the ECB if * arg0 (the dtrace_state_t) is equal to the ECB's * creating state. (This prevents disjoint consumers * from seeing one another's metaprobes.) */ if (arg0 != (uint64_t)(uintptr_t)state) continue; } if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) { /* * We're not currently active. If our provider isn't * the dtrace pseudo provider, we're not interested. */ if (prov != dtrace_provider) continue; /* * Now we must further check if we are in the BEGIN * probe. If we are, we will only continue processing * if we're still in WARMUP -- if one BEGIN enabling * has invoked the exit() action, we don't want to * evaluate subsequent BEGIN enablings. */ if (probe->dtpr_id == dtrace_probeid_begin && state->dts_activity != DTRACE_ACTIVITY_WARMUP) { ASSERT(state->dts_activity == DTRACE_ACTIVITY_DRAINING); continue; } } if (ecb->dte_cond) { /* * If the dte_cond bits indicate that this * consumer is only allowed to see user-mode firings * of this probe, call the provider's dtps_usermode() * entry point to check that the probe was fired * while in a user context. Skip this ECB if that's * not the case. */ if ((ecb->dte_cond & DTRACE_COND_USERMODE) && prov->dtpv_pops.dtps_usermode(prov->dtpv_arg, probe->dtpr_id, probe->dtpr_arg) == 0) continue; /* * This is more subtle than it looks. We have to be * absolutely certain that CRED() isn't going to * change out from under us so it's only legit to * examine that structure if we're in constrained * situations. Currently, the only times we'll this * check is if a non-super-user has enabled the * profile or syscall providers -- providers that * allow visibility of all processes. For the * profile case, the check above will ensure that * we're examining a user context. */ if (ecb->dte_cond & DTRACE_COND_OWNER) { cred_t *cr; cred_t *s_cr = ecb->dte_state->dts_cred.dcr_cred; proc_t *proc; #pragma unused(proc) /* __APPLE__ */ ASSERT(s_cr != NULL); /* * XXX this is hackish, but so is setting a variable * XXX in a McCarthy OR... */ if ((cr = dtrace_CRED()) == NULL || posix_cred_get(s_cr)->cr_uid != posix_cred_get(cr)->cr_uid || posix_cred_get(s_cr)->cr_uid != posix_cred_get(cr)->cr_ruid || posix_cred_get(s_cr)->cr_uid != posix_cred_get(cr)->cr_suid || posix_cred_get(s_cr)->cr_gid != posix_cred_get(cr)->cr_gid || posix_cred_get(s_cr)->cr_gid != posix_cred_get(cr)->cr_rgid || posix_cred_get(s_cr)->cr_gid != posix_cred_get(cr)->cr_sgid || #if !defined(__APPLE__) (proc = ttoproc(curthread)) == NULL || (proc->p_flag & SNOCD)) #else 1) /* APPLE NOTE: Darwin omits "No Core Dump" flag */ #endif /* __APPLE__ */ continue; } if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) { cred_t *cr; cred_t *s_cr = ecb->dte_state->dts_cred.dcr_cred; #pragma unused(cr, s_cr) /* __APPLE__ */ ASSERT(s_cr != NULL); #if !defined(__APPLE__) if ((cr = CRED()) == NULL || s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) continue; #else /* APPLE NOTE: Darwin doesn't do zones. */ #endif /* __APPLE__ */ } } if (now - state->dts_alive > dtrace_deadman_timeout) { /* * We seem to be dead. Unless we (a) have kernel * destructive permissions (b) have expicitly enabled * destructive actions and (c) destructive actions have * not been disabled, we're going to transition into * the KILLED state, from which no further processing * on this state will be performed. */ if (!dtrace_priv_kernel_destructive(state) || !state->dts_cred.dcr_destructive || dtrace_destructive_disallow) { void *activity = &state->dts_activity; dtrace_activity_t current; do { current = state->dts_activity; } while (dtrace_cas32(activity, current, DTRACE_ACTIVITY_KILLED) != current); continue; } } if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed, ecb->dte_alignment, state, &mstate)) < 0) continue; tomax = buf->dtb_tomax; ASSERT(tomax != NULL); if (ecb->dte_size != 0) DTRACE_STORE(uint32_t, tomax, offs, ecb->dte_epid); mstate.dtms_epid = ecb->dte_epid; mstate.dtms_present |= DTRACE_MSTATE_EPID; if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) mstate.dtms_access = DTRACE_ACCESS_KERNEL; else mstate.dtms_access = 0; if (pred != NULL) { dtrace_difo_t *dp = pred->dtp_difo; int rval; rval = dtrace_dif_emulate(dp, &mstate, vstate, state); if (!(*flags & CPU_DTRACE_ERROR) && !rval) { dtrace_cacheid_t cid = probe->dtpr_predcache; if (cid != DTRACE_CACHEIDNONE && !onintr) { /* * Update the predicate cache... */ ASSERT(cid == pred->dtp_cacheid); dtrace_set_thread_predcache(current_thread(), cid); } continue; } } for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) && act != NULL; act = act->dta_next) { size_t valoffs; dtrace_difo_t *dp; dtrace_recdesc_t *rec = &act->dta_rec; size = rec->dtrd_size; valoffs = offs + rec->dtrd_offset; if (DTRACEACT_ISAGG(act->dta_kind)) { uint64_t v = 0xbad; dtrace_aggregation_t *agg; agg = (dtrace_aggregation_t *)act; if ((dp = act->dta_difo) != NULL) v = dtrace_dif_emulate(dp, &mstate, vstate, state); if (*flags & CPU_DTRACE_ERROR) continue; /* * Note that we always pass the expression * value from the previous iteration of the * action loop. This value will only be used * if there is an expression argument to the * aggregating action, denoted by the * dtag_hasarg field. */ dtrace_aggregate(agg, buf, offs, aggbuf, v, val); continue; } switch (act->dta_kind) { case DTRACEACT_STOP: if (dtrace_priv_proc_destructive(state)) dtrace_action_stop(); continue; case DTRACEACT_BREAKPOINT: if (dtrace_priv_kernel_destructive(state)) dtrace_action_breakpoint(ecb); continue; case DTRACEACT_PANIC: if (dtrace_priv_kernel_destructive(state)) dtrace_action_panic(ecb); continue; case DTRACEACT_STACK: if (!dtrace_priv_kernel(state)) continue; dtrace_getpcstack((pc_t *)(tomax + valoffs), size / sizeof (pc_t), probe->dtpr_aframes, DTRACE_ANCHORED(probe) ? NULL : (uint32_t *)(uintptr_t)arg0); continue; case DTRACEACT_JSTACK: case DTRACEACT_USTACK: if (!dtrace_priv_proc(state)) continue; /* * See comment in DIF_VAR_PID. */ if (DTRACE_ANCHORED(mstate.dtms_probe) && CPU_ON_INTR(CPU)) { int depth = DTRACE_USTACK_NFRAMES( rec->dtrd_arg) + 1; dtrace_bzero((void *)(tomax + valoffs), DTRACE_USTACK_STRSIZE(rec->dtrd_arg) + depth * sizeof (uint64_t)); continue; } if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 && curproc->p_dtrace_helpers != NULL) { /* * This is the slow path -- we have * allocated string space, and we're * getting the stack of a process that * has helpers. Call into a separate * routine to perform this processing. */ dtrace_action_ustack(&mstate, state, (uint64_t *)(tomax + valoffs), rec->dtrd_arg); continue; } DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT); dtrace_getupcstack((uint64_t *) (tomax + valoffs), DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1); DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT); continue; default: break; } dp = act->dta_difo; ASSERT(dp != NULL); val = dtrace_dif_emulate(dp, &mstate, vstate, state); if (*flags & CPU_DTRACE_ERROR) continue; switch (act->dta_kind) { case DTRACEACT_SPECULATE: ASSERT(buf == &state->dts_buffer[cpuid]); buf = dtrace_speculation_buffer(state, cpuid, val); if (buf == NULL) { *flags |= CPU_DTRACE_DROP; continue; } offs = dtrace_buffer_reserve(buf, ecb->dte_needed, ecb->dte_alignment, state, NULL); if (offs < 0) { *flags |= CPU_DTRACE_DROP; continue; } tomax = buf->dtb_tomax; ASSERT(tomax != NULL); if (ecb->dte_size != 0) DTRACE_STORE(uint32_t, tomax, offs, ecb->dte_epid); continue; case DTRACEACT_CHILL: if (dtrace_priv_kernel_destructive(state)) dtrace_action_chill(&mstate, val); continue; case DTRACEACT_RAISE: if (dtrace_priv_proc_destructive(state)) dtrace_action_raise(val); continue; case DTRACEACT_PIDRESUME: /* __APPLE__ */ if (dtrace_priv_proc_destructive(state)) dtrace_action_pidresume(val); continue; case DTRACEACT_COMMIT: ASSERT(!committed); /* * We need to commit our buffer state. */ if (ecb->dte_size) buf->dtb_offset = offs + ecb->dte_size; buf = &state->dts_buffer[cpuid]; dtrace_speculation_commit(state, cpuid, val); committed = 1; continue; case DTRACEACT_DISCARD: dtrace_speculation_discard(state, cpuid, val); continue; case DTRACEACT_DIFEXPR: case DTRACEACT_LIBACT: case DTRACEACT_PRINTF: case DTRACEACT_PRINTA: case DTRACEACT_SYSTEM: case DTRACEACT_FREOPEN: case DTRACEACT_APPLEBINARY: /* __APPLE__ */ case DTRACEACT_TRACEMEM: break; case DTRACEACT_TRACEMEM_DYNSIZE: tracememsize = val; break; case DTRACEACT_SYM: case DTRACEACT_MOD: if (!dtrace_priv_kernel(state)) continue; break; case DTRACEACT_USYM: case DTRACEACT_UMOD: case DTRACEACT_UADDR: { if (!dtrace_priv_proc(state)) continue; DTRACE_STORE(uint64_t, tomax, valoffs, (uint64_t)dtrace_proc_selfpid()); DTRACE_STORE(uint64_t, tomax, valoffs + sizeof (uint64_t), val); continue; } case DTRACEACT_EXIT: { /* * For the exit action, we are going to attempt * to atomically set our activity to be * draining. If this fails (either because * another CPU has beat us to the exit action, * or because our current activity is something * other than ACTIVE or WARMUP), we will * continue. This assures that the exit action * can be successfully recorded at most once * when we're in the ACTIVE state. If we're * encountering the exit() action while in * COOLDOWN, however, we want to honor the new * status code. (We know that we're the only * thread in COOLDOWN, so there is no race.) */ void *activity = &state->dts_activity; dtrace_activity_t current = state->dts_activity; if (current == DTRACE_ACTIVITY_COOLDOWN) break; if (current != DTRACE_ACTIVITY_WARMUP) current = DTRACE_ACTIVITY_ACTIVE; if (dtrace_cas32(activity, current, DTRACE_ACTIVITY_DRAINING) != current) { *flags |= CPU_DTRACE_DROP; continue; } break; } default: ASSERT(0); } if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF) { uintptr_t end = valoffs + size; if (tracememsize != 0 && valoffs + tracememsize < end) { end = valoffs + tracememsize; tracememsize = 0; } if (!dtrace_vcanload((void *)(uintptr_t)val, &dp->dtdo_rtype, &mstate, vstate)) continue; /* * If this is a string, we're going to only * load until we find the zero byte -- after * which we'll store zero bytes. */ if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) { char c = '\0' + 1; int intuple = act->dta_intuple; size_t s; for (s = 0; s < size; s++) { if (c != '\0') c = dtrace_load8(val++); DTRACE_STORE(uint8_t, tomax, valoffs++, c); if (c == '\0' && intuple) break; } continue; } while (valoffs < end) { DTRACE_STORE(uint8_t, tomax, valoffs++, dtrace_load8(val++)); } continue; } switch (size) { case 0: break; case sizeof (uint8_t): DTRACE_STORE(uint8_t, tomax, valoffs, val); break; case sizeof (uint16_t): DTRACE_STORE(uint16_t, tomax, valoffs, val); break; case sizeof (uint32_t): DTRACE_STORE(uint32_t, tomax, valoffs, val); break; case sizeof (uint64_t): DTRACE_STORE(uint64_t, tomax, valoffs, val); break; default: /* * Any other size should have been returned by * reference, not by value. */ ASSERT(0); break; } } if (*flags & CPU_DTRACE_DROP) continue; if (*flags & CPU_DTRACE_FAULT) { int ndx; dtrace_action_t *err; buf->dtb_errors++; if (probe->dtpr_id == dtrace_probeid_error) { /* * There's nothing we can do -- we had an * error on the error probe. We bump an * error counter to at least indicate that * this condition happened. */ dtrace_error(&state->dts_dblerrors); continue; } if (vtime) { /* * Before recursing on dtrace_probe(), we * need to explicitly clear out our start * time to prevent it from being accumulated * into t_dtrace_vtime. */ /* * Darwin sets the sign bit on t_dtrace_tracing * to suspend accumulation to it. */ dtrace_set_thread_tracing(current_thread(), (1ULL<<63) | dtrace_get_thread_tracing(current_thread())); } /* * Iterate over the actions to figure out which action * we were processing when we experienced the error. * Note that act points _past_ the faulting action; if * act is ecb->dte_action, the fault was in the * predicate, if it's ecb->dte_action->dta_next it's * in action #1, and so on. */ for (err = ecb->dte_action, ndx = 0; err != act; err = err->dta_next, ndx++) continue; dtrace_probe_error(state, ecb->dte_epid, ndx, (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ? mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags), cpu_core[cpuid].cpuc_dtrace_illval); continue; } if (!committed) buf->dtb_offset = offs + ecb->dte_size; } /* FIXME: On Darwin the time spent leaving DTrace from this point to the rti is attributed to the current thread. Instead it should accrue to DTrace. */ if (vtime) { thread_t thread = current_thread(); int64_t t = dtrace_get_thread_tracing(thread); if (t >= 0) { /* Usual case, accumulate time spent here into t_dtrace_tracing */ dtrace_set_thread_tracing(thread, t + (dtrace_gethrtime() - now)); } else { /* Return from error recursion. No accumulation, just clear the sign bit on t_dtrace_tracing. */ dtrace_set_thread_tracing(thread, (~(1ULL<<63)) & t); } } dtrace_interrupt_enable(cookie); } /* * APPLE NOTE: Don't allow a thread to re-enter dtrace_probe(). * This could occur if a probe is encountered on some function in the * transitive closure of the call to dtrace_probe(). * Solaris has some strong guarantees that this won't happen. * The Darwin implementation is not so mature as to make those guarantees. * Hence, the introduction of __dtrace_probe() on xnu. */ void dtrace_probe(dtrace_id_t id, uint64_t arg0, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4) { thread_t thread = current_thread(); disable_preemption(); if (id == dtrace_probeid_error) { __dtrace_probe(id, arg0, arg1, arg2, arg3, arg4); dtrace_getipl(); /* Defeat tail-call optimization of __dtrace_probe() */ } else if (!dtrace_get_thread_reentering(thread)) { dtrace_set_thread_reentering(thread, TRUE); __dtrace_probe(id, arg0, arg1, arg2, arg3, arg4); dtrace_set_thread_reentering(thread, FALSE); } #if DEBUG else __dtrace_probe(dtrace_probeid_error, 0, id, 1, -1, DTRACEFLT_UNKNOWN); #endif enable_preemption(); } /* * DTrace Probe Hashing Functions * * The functions in this section (and indeed, the functions in remaining * sections) are not _called_ from probe context. (Any exceptions to this are * marked with a "Note:".) Rather, they are called from elsewhere in the * DTrace framework to look-up probes in, add probes to and remove probes from * the DTrace probe hashes. (Each probe is hashed by each element of the * probe tuple -- allowing for fast lookups, regardless of what was * specified.) */ static uint_t dtrace_hash_str(const char *p) { unsigned int g; uint_t hval = 0; while (*p) { hval = (hval << 4) + *p++; if ((g = (hval & 0xf0000000)) != 0) hval ^= g >> 24; hval &= ~g; } return (hval); } static dtrace_hash_t * dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs) { dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP); hash->dth_stroffs = stroffs; hash->dth_nextoffs = nextoffs; hash->dth_prevoffs = prevoffs; hash->dth_size = 1; hash->dth_mask = hash->dth_size - 1; hash->dth_tab = kmem_zalloc(hash->dth_size * sizeof (dtrace_hashbucket_t *), KM_SLEEP); return (hash); } /* * APPLE NOTE: dtrace_hash_destroy is not used. * It is called by dtrace_detach which is not * currently implemented. Revisit someday. */ #if !defined(__APPLE__) static void dtrace_hash_destroy(dtrace_hash_t *hash) { #if DEBUG int i; for (i = 0; i < hash->dth_size; i++) ASSERT(hash->dth_tab[i] == NULL); #endif kmem_free(hash->dth_tab, hash->dth_size * sizeof (dtrace_hashbucket_t *)); kmem_free(hash, sizeof (dtrace_hash_t)); } #endif /* __APPLE__ */ static void dtrace_hash_resize(dtrace_hash_t *hash) { int size = hash->dth_size, i, ndx; int new_size = hash->dth_size << 1; int new_mask = new_size - 1; dtrace_hashbucket_t **new_tab, *bucket, *next; ASSERT((new_size & new_mask) == 0); new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP); for (i = 0; i < size; i++) { for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) { dtrace_probe_t *probe = bucket->dthb_chain; ASSERT(probe != NULL); ndx = DTRACE_HASHSTR(hash, probe) & new_mask; next = bucket->dthb_next; bucket->dthb_next = new_tab[ndx]; new_tab[ndx] = bucket; } } kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *)); hash->dth_tab = new_tab; hash->dth_size = new_size; hash->dth_mask = new_mask; } static void dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new) { int hashval = DTRACE_HASHSTR(hash, new); int ndx = hashval & hash->dth_mask; dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; dtrace_probe_t **nextp, **prevp; for (; bucket != NULL; bucket = bucket->dthb_next) { if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new)) goto add; } if ((hash->dth_nbuckets >> 1) > hash->dth_size) { dtrace_hash_resize(hash); dtrace_hash_add(hash, new); return; } bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP); bucket->dthb_next = hash->dth_tab[ndx]; hash->dth_tab[ndx] = bucket; hash->dth_nbuckets++; add: nextp = DTRACE_HASHNEXT(hash, new); ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL); *nextp = bucket->dthb_chain; if (bucket->dthb_chain != NULL) { prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain); ASSERT(*prevp == NULL); *prevp = new; } bucket->dthb_chain = new; bucket->dthb_len++; } static dtrace_probe_t * dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template) { int hashval = DTRACE_HASHSTR(hash, template); int ndx = hashval & hash->dth_mask; dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; for (; bucket != NULL; bucket = bucket->dthb_next) { if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template)) return (bucket->dthb_chain); } return (NULL); } static int dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template) { int hashval = DTRACE_HASHSTR(hash, template); int ndx = hashval & hash->dth_mask; dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; for (; bucket != NULL; bucket = bucket->dthb_next) { if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template)) return (bucket->dthb_len); } return (0); } static void dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe) { int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask; dtrace_hashbucket_t *bucket = hash->dth_tab[ndx]; dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe); dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe); /* * Find the bucket that we're removing this probe from. */ for (; bucket != NULL; bucket = bucket->dthb_next) { if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe)) break; } ASSERT(bucket != NULL); if (*prevp == NULL) { if (*nextp == NULL) { /* * The removed probe was the only probe on this * bucket; we need to remove the bucket. */ dtrace_hashbucket_t *b = hash->dth_tab[ndx]; ASSERT(bucket->dthb_chain == probe); ASSERT(b != NULL); if (b == bucket) { hash->dth_tab[ndx] = bucket->dthb_next; } else { while (b->dthb_next != bucket) b = b->dthb_next; b->dthb_next = bucket->dthb_next; } ASSERT(hash->dth_nbuckets > 0); hash->dth_nbuckets--; kmem_free(bucket, sizeof (dtrace_hashbucket_t)); return; } bucket->dthb_chain = *nextp; } else { *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp; } if (*nextp != NULL) *(DTRACE_HASHPREV(hash, *nextp)) = *prevp; } /* * DTrace Utility Functions * * These are random utility functions that are _not_ called from probe context. */ static int dtrace_badattr(const dtrace_attribute_t *a) { return (a->dtat_name > DTRACE_STABILITY_MAX || a->dtat_data > DTRACE_STABILITY_MAX || a->dtat_class > DTRACE_CLASS_MAX); } /* * Return a duplicate copy of a string. If the specified string is NULL, * this function returns a zero-length string. * APPLE NOTE: Darwin employs size bounded string operation. */ static char * dtrace_strdup(const char *str) { size_t bufsize = (str != NULL ? strlen(str) : 0) + 1; char *new = kmem_zalloc(bufsize, KM_SLEEP); if (str != NULL) (void) strlcpy(new, str, bufsize); return (new); } #define DTRACE_ISALPHA(c) \ (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z')) static int dtrace_badname(const char *s) { char c; if (s == NULL || (c = *s++) == '\0') return (0); if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.') return (1); while ((c = *s++) != '\0') { if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') && c != '-' && c != '_' && c != '.' && c != '`') return (1); } return (0); } static void dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp) { uint32_t priv; if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) { /* * For DTRACE_PRIV_ALL, the uid and zoneid don't matter. */ priv = DTRACE_PRIV_ALL; } else { *uidp = crgetuid(cr); *zoneidp = crgetzoneid(cr); priv = 0; if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER; else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) priv |= DTRACE_PRIV_USER; if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) priv |= DTRACE_PRIV_PROC; if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) priv |= DTRACE_PRIV_OWNER; if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) priv |= DTRACE_PRIV_ZONEOWNER; } *privp = priv; } #ifdef DTRACE_ERRDEBUG static void dtrace_errdebug(const char *str) { int hval = dtrace_hash_str(str) % DTRACE_ERRHASHSZ; int occupied = 0; lck_mtx_lock(&dtrace_errlock); dtrace_errlast = str; dtrace_errthread = (kthread_t *)current_thread(); while (occupied++ < DTRACE_ERRHASHSZ) { if (dtrace_errhash[hval].dter_msg == str) { dtrace_errhash[hval].dter_count++; goto out; } if (dtrace_errhash[hval].dter_msg != NULL) { hval = (hval + 1) % DTRACE_ERRHASHSZ; continue; } dtrace_errhash[hval].dter_msg = str; dtrace_errhash[hval].dter_count = 1; goto out; } panic("dtrace: undersized error hash"); out: lck_mtx_unlock(&dtrace_errlock); } #endif /* * DTrace Matching Functions * * These functions are used to match groups of probes, given some elements of * a probe tuple, or some globbed expressions for elements of a probe tuple. */ static int dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid, zoneid_t zoneid) { if (priv != DTRACE_PRIV_ALL) { uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags; uint32_t match = priv & ppriv; /* * No PRIV_DTRACE_* privileges... */ if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER | DTRACE_PRIV_KERNEL)) == 0) return (0); /* * No matching bits, but there were bits to match... */ if (match == 0 && ppriv != 0) return (0); /* * Need to have permissions to the process, but don't... */ if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 && uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) { return (0); } /* * Need to be in the same zone unless we possess the * privilege to examine all zones. */ if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 && zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) { return (0); } } return (1); } /* * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which * consists of input pattern strings and an ops-vector to evaluate them. * This function returns >0 for match, 0 for no match, and <0 for error. */ static int dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid, zoneid_t zoneid) { dtrace_provider_t *pvp = prp->dtpr_provider; int rv; if (pvp->dtpv_defunct) return (0); if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0) return (rv); if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0) return (rv); if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0) return (rv); if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0) return (rv); if (dtrace_match_priv(prp, priv, uid, zoneid) == 0) return (0); return (rv); } /* * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN) * interface for matching a glob pattern 'p' to an input string 's'. Unlike * libc's version, the kernel version only applies to 8-bit ASCII strings. * In addition, all of the recursion cases except for '*' matching have been * unwound. For '*', we still implement recursive evaluation, but a depth * counter is maintained and matching is aborted if we recurse too deep. * The function returns 0 if no match, >0 if match, and <0 if recursion error. */ static int dtrace_match_glob(const char *s, const char *p, int depth) { const char *olds; char s1, c; int gs; if (depth > DTRACE_PROBEKEY_MAXDEPTH) return (-1); if (s == NULL) s = ""; /* treat NULL as empty string */ top: olds = s; s1 = *s++; if (p == NULL) return (0); if ((c = *p++) == '\0') return (s1 == '\0'); switch (c) { case '[': { int ok = 0, notflag = 0; char lc = '\0'; if (s1 == '\0') return (0); if (*p == '!') { notflag = 1; p++; } if ((c = *p++) == '\0') return (0); do { if (c == '-' && lc != '\0' && *p != ']') { if ((c = *p++) == '\0') return (0); if (c == '\\' && (c = *p++) == '\0') return (0); if (notflag) { if (s1 < lc || s1 > c) ok++; else return (0); } else if (lc <= s1 && s1 <= c) ok++; } else if (c == '\\' && (c = *p++) == '\0') return (0); lc = c; /* save left-hand 'c' for next iteration */ if (notflag) { if (s1 != c) ok++; else return (0); } else if (s1 == c) ok++; if ((c = *p++) == '\0') return (0); } while (c != ']'); if (ok) goto top; return (0); } case '\\': if ((c = *p++) == '\0') return (0); /*FALLTHRU*/ default: if (c != s1) return (0); /*FALLTHRU*/ case '?': if (s1 != '\0') goto top; return (0); case '*': while (*p == '*') p++; /* consecutive *'s are identical to a single one */ if (*p == '\0') return (1); for (s = olds; *s != '\0'; s++) { if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0) return (gs); } return (0); } } /*ARGSUSED*/ static int dtrace_match_string(const char *s, const char *p, int depth) { #pragma unused(depth) /* __APPLE__ */ /* APPLE NOTE: Darwin employs size bounded string operation. */ return (s != NULL && strncmp(s, p, strlen(s) + 1) == 0); } /*ARGSUSED*/ static int dtrace_match_nul(const char *s, const char *p, int depth) { #pragma unused(s, p, depth) /* __APPLE__ */ return (1); /* always match the empty pattern */ } /*ARGSUSED*/ static int dtrace_match_nonzero(const char *s, const char *p, int depth) { #pragma unused(p, depth) /* __APPLE__ */ return (s != NULL && s[0] != '\0'); } static int dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid, zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg) { dtrace_probe_t template, *probe; dtrace_hash_t *hash = NULL; int len, rc, best = INT_MAX, nmatched = 0; dtrace_id_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); /* * If the probe ID is specified in the key, just lookup by ID and * invoke the match callback once if a matching probe is found. */ if (pkp->dtpk_id != DTRACE_IDNONE) { if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL && dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) { if ((*matched)(probe, arg) == DTRACE_MATCH_FAIL) return (DTRACE_MATCH_FAIL); nmatched++; } return (nmatched); } template.dtpr_mod = (char *)(uintptr_t)pkp->dtpk_mod; template.dtpr_func = (char *)(uintptr_t)pkp->dtpk_func; template.dtpr_name = (char *)(uintptr_t)pkp->dtpk_name; /* * We want to find the most distinct of the module name, function * name, and name. So for each one that is not a glob pattern or * empty string, we perform a lookup in the corresponding hash and * use the hash table with the fewest collisions to do our search. */ if (pkp->dtpk_mmatch == &dtrace_match_string && (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) { best = len; hash = dtrace_bymod; } if (pkp->dtpk_fmatch == &dtrace_match_string && (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) { best = len; hash = dtrace_byfunc; } if (pkp->dtpk_nmatch == &dtrace_match_string && (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) { best = len; hash = dtrace_byname; } /* * If we did not select a hash table, iterate over every probe and * invoke our callback for each one that matches our input probe key. */ if (hash == NULL) { for (i = 0; i < (dtrace_id_t)dtrace_nprobes; i++) { if ((probe = dtrace_probes[i]) == NULL || dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0) continue; nmatched++; if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) { if (rc == DTRACE_MATCH_FAIL) return (DTRACE_MATCH_FAIL); break; } } return (nmatched); } /* * If we selected a hash table, iterate over each probe of the same key * name and invoke the callback for every probe that matches the other * attributes of our input probe key. */ for (probe = dtrace_hash_lookup(hash, &template); probe != NULL; probe = *(DTRACE_HASHNEXT(hash, probe))) { if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0) continue; nmatched++; if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) { if (rc == DTRACE_MATCH_FAIL) return (DTRACE_MATCH_FAIL); break; } } return (nmatched); } /* * Return the function pointer dtrace_probecmp() should use to compare the * specified pattern with a string. For NULL or empty patterns, we select * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob(). * For non-empty non-glob strings, we use dtrace_match_string(). */ static dtrace_probekey_f * dtrace_probekey_func(const char *p) { char c; if (p == NULL || *p == '\0') return (&dtrace_match_nul); while ((c = *p++) != '\0') { if (c == '[' || c == '?' || c == '*' || c == '\\') return (&dtrace_match_glob); } return (&dtrace_match_string); } /* * Build a probe comparison key for use with dtrace_match_probe() from the * given probe description. By convention, a null key only matches anchored * probes: if each field is the empty string, reset dtpk_fmatch to * dtrace_match_nonzero(). */ static void dtrace_probekey(const dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp) { pkp->dtpk_prov = pdp->dtpd_provider; pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider); pkp->dtpk_mod = pdp->dtpd_mod; pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod); pkp->dtpk_func = pdp->dtpd_func; pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func); pkp->dtpk_name = pdp->dtpd_name; pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name); pkp->dtpk_id = pdp->dtpd_id; if (pkp->dtpk_id == DTRACE_IDNONE && pkp->dtpk_pmatch == &dtrace_match_nul && pkp->dtpk_mmatch == &dtrace_match_nul && pkp->dtpk_fmatch == &dtrace_match_nul && pkp->dtpk_nmatch == &dtrace_match_nul) pkp->dtpk_fmatch = &dtrace_match_nonzero; } /* * DTrace Provider-to-Framework API Functions * * These functions implement much of the Provider-to-Framework API, as * described in . The parts of the API not in this section are * the functions in the API for probe management (found below), and * dtrace_probe() itself (found above). */ /* * Register the calling provider with the DTrace framework. This should * generally be called by DTrace providers in their attach(9E) entry point. */ int dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv, cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp) { dtrace_provider_t *provider; if (name == NULL || pap == NULL || pops == NULL || idp == NULL) { cmn_err(CE_WARN, "failed to register provider '%s': invalid " "arguments", name ? name : ""); return (EINVAL); } if (name[0] == '\0' || dtrace_badname(name)) { cmn_err(CE_WARN, "failed to register provider '%s': invalid " "provider name", name); return (EINVAL); } if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) || pops->dtps_enable == NULL || pops->dtps_disable == NULL || pops->dtps_destroy == NULL || ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) { cmn_err(CE_WARN, "failed to register provider '%s': invalid " "provider ops", name); return (EINVAL); } if (dtrace_badattr(&pap->dtpa_provider) || dtrace_badattr(&pap->dtpa_mod) || dtrace_badattr(&pap->dtpa_func) || dtrace_badattr(&pap->dtpa_name) || dtrace_badattr(&pap->dtpa_args)) { cmn_err(CE_WARN, "failed to register provider '%s': invalid " "provider attributes", name); return (EINVAL); } if (priv & ~DTRACE_PRIV_ALL) { cmn_err(CE_WARN, "failed to register provider '%s': invalid " "privilege attributes", name); return (EINVAL); } if ((priv & DTRACE_PRIV_KERNEL) && (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) && pops->dtps_usermode == NULL) { cmn_err(CE_WARN, "failed to register provider '%s': need " "dtps_usermode() op for given privilege attributes", name); return (EINVAL); } provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP); /* APPLE NOTE: Darwin employs size bounded string operation. */ { size_t bufsize = strlen(name) + 1; provider->dtpv_name = kmem_alloc(bufsize, KM_SLEEP); (void) strlcpy(provider->dtpv_name, name, bufsize); } provider->dtpv_attr = *pap; provider->dtpv_priv.dtpp_flags = priv; if (cr != NULL) { provider->dtpv_priv.dtpp_uid = crgetuid(cr); provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr); } provider->dtpv_pops = *pops; if (pops->dtps_provide == NULL) { ASSERT(pops->dtps_provide_module != NULL); provider->dtpv_pops.dtps_provide = (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop; } if (pops->dtps_provide_module == NULL) { ASSERT(pops->dtps_provide != NULL); provider->dtpv_pops.dtps_provide_module = (void (*)(void *, struct modctl *))dtrace_nullop; } if (pops->dtps_suspend == NULL) { ASSERT(pops->dtps_resume == NULL); provider->dtpv_pops.dtps_suspend = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop; provider->dtpv_pops.dtps_resume = (void (*)(void *, dtrace_id_t, void *))dtrace_nullop; } provider->dtpv_arg = arg; *idp = (dtrace_provider_id_t)provider; if (pops == &dtrace_provider_ops) { lck_mtx_assert(&dtrace_provider_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dtrace_anon.dta_enabling == NULL); /* * We make sure that the DTrace provider is at the head of * the provider chain. */ provider->dtpv_next = dtrace_provider; dtrace_provider = provider; return (0); } lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); /* * If there is at least one provider registered, we'll add this * provider after the first provider. */ if (dtrace_provider != NULL) { provider->dtpv_next = dtrace_provider->dtpv_next; dtrace_provider->dtpv_next = provider; } else { dtrace_provider = provider; } if (dtrace_retained != NULL) { dtrace_enabling_provide(provider); /* * Now we need to call dtrace_enabling_matchall() -- which * will acquire cpu_lock and dtrace_lock. We therefore need * to drop all of our locks before calling into it... */ lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); dtrace_enabling_matchall(); return (0); } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); return (0); } /* * Unregister the specified provider from the DTrace framework. This should * generally be called by DTrace providers in their detach(9E) entry point. */ int dtrace_unregister(dtrace_provider_id_t id) { dtrace_provider_t *old = (dtrace_provider_t *)id; dtrace_provider_t *prev = NULL; int i, self = 0; dtrace_probe_t *probe, *first = NULL; if (old->dtpv_pops.dtps_enable == (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop) { /* * If DTrace itself is the provider, we're called with locks * already held. */ ASSERT(old == dtrace_provider); ASSERT(dtrace_devi != NULL); lck_mtx_assert(&dtrace_provider_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); self = 1; if (dtrace_provider->dtpv_next != NULL) { /* * There's another provider here; return failure. */ return (EBUSY); } } else { lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&mod_lock); lck_mtx_lock(&dtrace_lock); } /* * If anyone has /dev/dtrace open, or if there are anonymous enabled * probes, we refuse to let providers slither away, unless this * provider has already been explicitly invalidated. */ if (!old->dtpv_defunct && (dtrace_opens || (dtrace_anon.dta_state != NULL && dtrace_anon.dta_state->dts_necbs > 0))) { if (!self) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); } return (EBUSY); } /* * Attempt to destroy the probes associated with this provider. */ if (old->dtpv_ecb_count!=0) { /* * We have at least one ECB; we can't remove this provider. */ if (!self) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); } return (EBUSY); } /* * All of the probes for this provider are disabled; we can safely * remove all of them from their hash chains and from the probe array. */ for (i = 0; i < dtrace_nprobes && old->dtpv_probe_count!=0; i++) { if ((probe = dtrace_probes[i]) == NULL) continue; if (probe->dtpr_provider != old) continue; dtrace_probes[i] = NULL; old->dtpv_probe_count--; dtrace_hash_remove(dtrace_bymod, probe); dtrace_hash_remove(dtrace_byfunc, probe); dtrace_hash_remove(dtrace_byname, probe); if (first == NULL) { first = probe; probe->dtpr_nextmod = NULL; } else { probe->dtpr_nextmod = first; first = probe; } } /* * The provider's probes have been removed from the hash chains and * from the probe array. Now issue a dtrace_sync() to be sure that * everyone has cleared out from any probe array processing. */ dtrace_sync(); for (probe = first; probe != NULL; probe = first) { first = probe->dtpr_nextmod; old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id, probe->dtpr_arg); kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1); zfree(dtrace_probe_t_zone, probe); } if ((prev = dtrace_provider) == old) { ASSERT(self || dtrace_devi == NULL); ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL); dtrace_provider = old->dtpv_next; } else { while (prev != NULL && prev->dtpv_next != old) prev = prev->dtpv_next; if (prev == NULL) { panic("attempt to unregister non-existent " "dtrace provider %p\n", (void *)id); } prev->dtpv_next = old->dtpv_next; } if (!self) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); } kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1); kmem_free(old, sizeof (dtrace_provider_t)); return (0); } /* * Invalidate the specified provider. All subsequent probe lookups for the * specified provider will fail, but its probes will not be removed. */ void dtrace_invalidate(dtrace_provider_id_t id) { dtrace_provider_t *pvp = (dtrace_provider_t *)id; ASSERT(pvp->dtpv_pops.dtps_enable != (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); pvp->dtpv_defunct = 1; lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); } /* * Indicate whether or not DTrace has attached. */ int dtrace_attached(void) { /* * dtrace_provider will be non-NULL iff the DTrace driver has * attached. (It's non-NULL because DTrace is always itself a * provider.) */ return (dtrace_provider != NULL); } /* * Remove all the unenabled probes for the given provider. This function is * not unlike dtrace_unregister(), except that it doesn't remove the provider * -- just as many of its associated probes as it can. */ int dtrace_condense(dtrace_provider_id_t id) { dtrace_provider_t *prov = (dtrace_provider_t *)id; int i; dtrace_probe_t *probe; /* * Make sure this isn't the dtrace provider itself. */ ASSERT(prov->dtpv_pops.dtps_enable != (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); /* * Attempt to destroy the probes associated with this provider. */ for (i = 0; i < dtrace_nprobes; i++) { if ((probe = dtrace_probes[i]) == NULL) continue; if (probe->dtpr_provider != prov) continue; if (probe->dtpr_ecb != NULL) continue; dtrace_probes[i] = NULL; prov->dtpv_probe_count--; dtrace_hash_remove(dtrace_bymod, probe); dtrace_hash_remove(dtrace_byfunc, probe); dtrace_hash_remove(dtrace_byname, probe); prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1, probe->dtpr_arg); kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); zfree(dtrace_probe_t_zone, probe); vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1); } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); return (0); } /* * DTrace Probe Management Functions * * The functions in this section perform the DTrace probe management, * including functions to create probes, look-up probes, and call into the * providers to request that probes be provided. Some of these functions are * in the Provider-to-Framework API; these functions can be identified by the * fact that they are not declared "static". */ /* * Create a probe with the specified module name, function name, and name. */ dtrace_id_t dtrace_probe_create(dtrace_provider_id_t prov, const char *mod, const char *func, const char *name, int aframes, void *arg) { dtrace_probe_t *probe, **probes; dtrace_provider_t *provider = (dtrace_provider_t *)prov; dtrace_id_t id; if (provider == dtrace_provider) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); } else { lck_mtx_lock(&dtrace_lock); } id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1, VM_BESTFIT | VM_SLEEP); probe = zalloc(dtrace_probe_t_zone); bzero(probe, sizeof (dtrace_probe_t)); probe->dtpr_id = id; probe->dtpr_gen = dtrace_probegen++; probe->dtpr_mod = dtrace_strdup(mod); probe->dtpr_func = dtrace_strdup(func); probe->dtpr_name = dtrace_strdup(name); probe->dtpr_arg = arg; probe->dtpr_aframes = aframes; probe->dtpr_provider = provider; dtrace_hash_add(dtrace_bymod, probe); dtrace_hash_add(dtrace_byfunc, probe); dtrace_hash_add(dtrace_byname, probe); if (id - 1 >= (dtrace_id_t)dtrace_nprobes) { size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *); size_t nsize = osize << 1; if (nsize == 0) { ASSERT(osize == 0); ASSERT(dtrace_probes == NULL); nsize = sizeof (dtrace_probe_t *); } probes = kmem_zalloc(nsize, KM_SLEEP); if (dtrace_probes == NULL) { ASSERT(osize == 0); dtrace_probes = probes; dtrace_nprobes = 1; } else { dtrace_probe_t **oprobes = dtrace_probes; bcopy(oprobes, probes, osize); dtrace_membar_producer(); dtrace_probes = probes; dtrace_sync(); /* * All CPUs are now seeing the new probes array; we can * safely free the old array. */ kmem_free(oprobes, osize); dtrace_nprobes <<= 1; } ASSERT(id - 1 < (dtrace_id_t)dtrace_nprobes); } ASSERT(dtrace_probes[id - 1] == NULL); dtrace_probes[id - 1] = probe; provider->dtpv_probe_count++; if (provider != dtrace_provider) lck_mtx_unlock(&dtrace_lock); return (id); } static dtrace_probe_t * dtrace_probe_lookup_id(dtrace_id_t id) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (id == 0 || id > (dtrace_id_t)dtrace_nprobes) return (NULL); return (dtrace_probes[id - 1]); } static int dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg) { *((dtrace_id_t *)arg) = probe->dtpr_id; return (DTRACE_MATCH_DONE); } /* * Look up a probe based on provider and one or more of module name, function * name and probe name. */ dtrace_id_t dtrace_probe_lookup(dtrace_provider_id_t prid, const char *mod, const char *func, const char *name) { dtrace_probekey_t pkey; dtrace_id_t id; int match; pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name; pkey.dtpk_pmatch = &dtrace_match_string; pkey.dtpk_mod = mod; pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul; pkey.dtpk_func = func; pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul; pkey.dtpk_name = name; pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul; pkey.dtpk_id = DTRACE_IDNONE; lck_mtx_lock(&dtrace_lock); match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0, dtrace_probe_lookup_match, &id); lck_mtx_unlock(&dtrace_lock); ASSERT(match == 1 || match == 0); return (match ? id : 0); } /* * Returns the probe argument associated with the specified probe. */ void * dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid) { dtrace_probe_t *probe; void *rval = NULL; lck_mtx_lock(&dtrace_lock); if ((probe = dtrace_probe_lookup_id(pid)) != NULL && probe->dtpr_provider == (dtrace_provider_t *)id) rval = probe->dtpr_arg; lck_mtx_unlock(&dtrace_lock); return (rval); } /* * Copy a probe into a probe description. */ static void dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp) { bzero(pdp, sizeof (dtrace_probedesc_t)); pdp->dtpd_id = prp->dtpr_id; /* APPLE NOTE: Darwin employs size bounded string operation. */ (void) strlcpy(pdp->dtpd_provider, prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN); (void) strlcpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN); (void) strlcpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN); (void) strlcpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN); } /* * Called to indicate that a probe -- or probes -- should be provided by a * specfied provider. If the specified description is NULL, the provider will * be told to provide all of its probes. (This is done whenever a new * consumer comes along, or whenever a retained enabling is to be matched.) If * the specified description is non-NULL, the provider is given the * opportunity to dynamically provide the specified probe, allowing providers * to support the creation of probes on-the-fly. (So-called _autocreated_ * probes.) If the provider is NULL, the operations will be applied to all * providers; if the provider is non-NULL the operations will only be applied * to the specified provider. The dtrace_provider_lock must be held, and the * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation * will need to grab the dtrace_lock when it reenters the framework through * dtrace_probe_lookup(), dtrace_probe_create(), etc. */ static void dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv) { struct modctl *ctl; int all = 0; lck_mtx_assert(&dtrace_provider_lock, LCK_MTX_ASSERT_OWNED); if (prv == NULL) { all = 1; prv = dtrace_provider; } do { /* * First, call the blanket provide operation. */ prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc); /* * Now call the per-module provide operation. We will grab * mod_lock to prevent the list from being modified. Note * that this also prevents the mod_busy bits from changing. * (mod_busy can only be changed with mod_lock held.) */ lck_mtx_lock(&mod_lock); ctl = dtrace_modctl_list; while (ctl) { prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl); ctl = ctl->mod_next; } lck_mtx_unlock(&mod_lock); } while (all && (prv = prv->dtpv_next) != NULL); } /* * Iterate over each probe, and call the Framework-to-Provider API function * denoted by offs. */ static void dtrace_probe_foreach(uintptr_t offs) { dtrace_provider_t *prov; void (*func)(void *, dtrace_id_t, void *); dtrace_probe_t *probe; dtrace_icookie_t cookie; int i; /* * We disable interrupts to walk through the probe array. This is * safe -- the dtrace_sync() in dtrace_unregister() assures that we * won't see stale data. */ cookie = dtrace_interrupt_disable(); for (i = 0; i < dtrace_nprobes; i++) { if ((probe = dtrace_probes[i]) == NULL) continue; if (probe->dtpr_ecb == NULL) { /* * This probe isn't enabled -- don't call the function. */ continue; } prov = probe->dtpr_provider; func = *((void(**)(void *, dtrace_id_t, void *)) ((uintptr_t)&prov->dtpv_pops + offs)); func(prov->dtpv_arg, i + 1, probe->dtpr_arg); } dtrace_interrupt_enable(cookie); } static int dtrace_probe_enable(const dtrace_probedesc_t *desc, dtrace_enabling_t *enab) { dtrace_probekey_t pkey; uint32_t priv; uid_t uid; zoneid_t zoneid; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); dtrace_ecb_create_cache = NULL; if (desc == NULL) { /* * If we're passed a NULL description, we're being asked to * create an ECB with a NULL probe. */ (void) dtrace_ecb_create_enable(NULL, enab); return (0); } dtrace_probekey(desc, &pkey); dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred, &priv, &uid, &zoneid); return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable, enab)); } /* * DTrace Helper Provider Functions */ static void dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr) { attr->dtat_name = DOF_ATTR_NAME(dofattr); attr->dtat_data = DOF_ATTR_DATA(dofattr); attr->dtat_class = DOF_ATTR_CLASS(dofattr); } static void dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov, const dof_provider_t *dofprov, char *strtab) { hprov->dthpv_provname = strtab + dofprov->dofpv_name; dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider, dofprov->dofpv_provattr); dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod, dofprov->dofpv_modattr); dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func, dofprov->dofpv_funcattr); dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name, dofprov->dofpv_nameattr); dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args, dofprov->dofpv_argsattr); } static void dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid) { uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; dof_hdr_t *dof = (dof_hdr_t *)daddr; dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec; dof_provider_t *provider; dof_probe_t *probe; uint32_t *off, *enoff; uint8_t *arg; char *strtab; uint_t i, nprobes; dtrace_helper_provdesc_t dhpv; dtrace_helper_probedesc_t dhpb; dtrace_meta_t *meta = dtrace_meta_pid; dtrace_mops_t *mops = &meta->dtm_mops; void *parg; provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_strtab * dof->dofh_secsize); prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_probes * dof->dofh_secsize); arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_prargs * dof->dofh_secsize); off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_proffs * dof->dofh_secsize); strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset); arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset); enoff = NULL; /* * See dtrace_helper_provider_validate(). */ if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 && provider->dofpv_prenoffs != DOF_SECT_NONE) { enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_prenoffs * dof->dofh_secsize); enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset); } nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize; /* * Create the provider. */ dtrace_dofprov2hprov(&dhpv, provider, strtab); if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL) return; meta->dtm_count++; /* * Create the probes. */ for (i = 0; i < nprobes; i++) { probe = (dof_probe_t *)(uintptr_t)(daddr + prb_sec->dofs_offset + i * prb_sec->dofs_entsize); dhpb.dthpb_mod = dhp->dofhp_mod; dhpb.dthpb_func = strtab + probe->dofpr_func; dhpb.dthpb_name = strtab + probe->dofpr_name; #if !defined(__APPLE__) dhpb.dthpb_base = probe->dofpr_addr; #else dhpb.dthpb_base = dhp->dofhp_addr; /* FIXME: James, why? */ #endif dhpb.dthpb_offs = (int32_t *)(off + probe->dofpr_offidx); dhpb.dthpb_noffs = probe->dofpr_noffs; if (enoff != NULL) { dhpb.dthpb_enoffs = (int32_t *)(enoff + probe->dofpr_enoffidx); dhpb.dthpb_nenoffs = probe->dofpr_nenoffs; } else { dhpb.dthpb_enoffs = NULL; dhpb.dthpb_nenoffs = 0; } dhpb.dthpb_args = arg + probe->dofpr_argidx; dhpb.dthpb_nargc = probe->dofpr_nargc; dhpb.dthpb_xargc = probe->dofpr_xargc; dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv; dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv; mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb); } } static void dtrace_helper_provide(dof_helper_t *dhp, pid_t pid) { uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; dof_hdr_t *dof = (dof_hdr_t *)daddr; uint32_t i; lck_mtx_assert(&dtrace_meta_lock, LCK_MTX_ASSERT_OWNED); for (i = 0; i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + i * dof->dofh_secsize); if (sec->dofs_type != DOF_SECT_PROVIDER) continue; dtrace_helper_provide_one(dhp, sec, pid); } /* * We may have just created probes, so we must now rematch against * any retained enablings. Note that this call will acquire both * cpu_lock and dtrace_lock; the fact that we are holding * dtrace_meta_lock now is what defines the ordering with respect to * these three locks. */ dtrace_enabling_matchall(); } static void dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid) { uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; dof_hdr_t *dof = (dof_hdr_t *)daddr; dof_sec_t *str_sec; dof_provider_t *provider; char *strtab; dtrace_helper_provdesc_t dhpv; dtrace_meta_t *meta = dtrace_meta_pid; dtrace_mops_t *mops = &meta->dtm_mops; provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + provider->dofpv_strtab * dof->dofh_secsize); strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); /* * Create the provider. */ dtrace_dofprov2hprov(&dhpv, provider, strtab); mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid); meta->dtm_count--; } static void dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid) { uintptr_t daddr = (uintptr_t)dhp->dofhp_dof; dof_hdr_t *dof = (dof_hdr_t *)daddr; uint32_t i; lck_mtx_assert(&dtrace_meta_lock, LCK_MTX_ASSERT_OWNED); for (i = 0; i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + i * dof->dofh_secsize); if (sec->dofs_type != DOF_SECT_PROVIDER) continue; dtrace_helper_provider_remove_one(dhp, sec, pid); } } /* * DTrace Meta Provider-to-Framework API Functions * * These functions implement the Meta Provider-to-Framework API, as described * in . */ int dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg, dtrace_meta_provider_id_t *idp) { dtrace_meta_t *meta; dtrace_helpers_t *help, *next; uint_t i; *idp = DTRACE_METAPROVNONE; /* * We strictly don't need the name, but we hold onto it for * debuggability. All hail error queues! */ if (name == NULL) { cmn_err(CE_WARN, "failed to register meta-provider: " "invalid name"); return (EINVAL); } if (mops == NULL || mops->dtms_create_probe == NULL || mops->dtms_provide_pid == NULL || mops->dtms_remove_pid == NULL) { cmn_err(CE_WARN, "failed to register meta-register %s: " "invalid ops", name); return (EINVAL); } meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP); meta->dtm_mops = *mops; /* APPLE NOTE: Darwin employs size bounded string operation. */ { size_t bufsize = strlen(name) + 1; meta->dtm_name = kmem_alloc(bufsize, KM_SLEEP); (void) strlcpy(meta->dtm_name, name, bufsize); } meta->dtm_arg = arg; lck_mtx_lock(&dtrace_meta_lock); lck_mtx_lock(&dtrace_lock); if (dtrace_meta_pid != NULL) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_meta_lock); cmn_err(CE_WARN, "failed to register meta-register %s: " "user-land meta-provider exists", name); kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1); kmem_free(meta, sizeof (dtrace_meta_t)); return (EINVAL); } dtrace_meta_pid = meta; *idp = (dtrace_meta_provider_id_t)meta; /* * If there are providers and probes ready to go, pass them * off to the new meta provider now. */ help = dtrace_deferred_pid; dtrace_deferred_pid = NULL; lck_mtx_unlock(&dtrace_lock); while (help != NULL) { for (i = 0; i < help->dthps_nprovs; i++) { dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov, help->dthps_pid); } next = help->dthps_next; help->dthps_next = NULL; help->dthps_prev = NULL; help->dthps_deferred = 0; help = next; } lck_mtx_unlock(&dtrace_meta_lock); return (0); } int dtrace_meta_unregister(dtrace_meta_provider_id_t id) { dtrace_meta_t **pp, *old = (dtrace_meta_t *)id; lck_mtx_lock(&dtrace_meta_lock); lck_mtx_lock(&dtrace_lock); if (old == dtrace_meta_pid) { pp = &dtrace_meta_pid; } else { panic("attempt to unregister non-existent " "dtrace meta-provider %p\n", (void *)old); } if (old->dtm_count != 0) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_meta_lock); return (EBUSY); } *pp = NULL; lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_meta_lock); kmem_free(old->dtm_name, strlen(old->dtm_name) + 1); kmem_free(old, sizeof (dtrace_meta_t)); return (0); } /* * DTrace DIF Object Functions */ static int dtrace_difo_err(uint_t pc, const char *format, ...) { if (dtrace_err_verbose) { va_list alist; (void) uprintf("dtrace DIF object error: [%u]: ", pc); va_start(alist, format); (void) vuprintf(format, alist); va_end(alist); } #ifdef DTRACE_ERRDEBUG dtrace_errdebug(format); #endif return (1); } /* * Validate a DTrace DIF object by checking the IR instructions. The following * rules are currently enforced by dtrace_difo_validate(): * * 1. Each instruction must have a valid opcode * 2. Each register, string, variable, or subroutine reference must be valid * 3. No instruction can modify register %r0 (must be zero) * 4. All instruction reserved bits must be set to zero * 5. The last instruction must be a "ret" instruction * 6. All branch targets must reference a valid instruction _after_ the branch */ static int dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs, cred_t *cr) { int err = 0; uint_t i; int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err; int kcheckload; uint_t pc; kcheckload = cr == NULL || (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0; dp->dtdo_destructive = 0; for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) { dif_instr_t instr = dp->dtdo_buf[pc]; uint_t r1 = DIF_INSTR_R1(instr); uint_t r2 = DIF_INSTR_R2(instr); uint_t rd = DIF_INSTR_RD(instr); uint_t rs = DIF_INSTR_RS(instr); uint_t label = DIF_INSTR_LABEL(instr); uint_t v = DIF_INSTR_VAR(instr); uint_t subr = DIF_INSTR_SUBR(instr); uint_t type = DIF_INSTR_TYPE(instr); uint_t op = DIF_INSTR_OP(instr); switch (op) { case DIF_OP_OR: case DIF_OP_XOR: case DIF_OP_AND: case DIF_OP_SLL: case DIF_OP_SRL: case DIF_OP_SRA: case DIF_OP_SUB: case DIF_OP_ADD: case DIF_OP_MUL: case DIF_OP_SDIV: case DIF_OP_UDIV: case DIF_OP_SREM: case DIF_OP_UREM: case DIF_OP_COPYS: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 >= nregs) err += efunc(pc, "invalid register %u\n", r2); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_NOT: case DIF_OP_MOV: case DIF_OP_ALLOCS: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_LDSB: case DIF_OP_LDSH: case DIF_OP_LDSW: case DIF_OP_LDUB: case DIF_OP_LDUH: case DIF_OP_LDUW: case DIF_OP_LDX: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); if (kcheckload) dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op + DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd); break; case DIF_OP_RLDSB: case DIF_OP_RLDSH: case DIF_OP_RLDSW: case DIF_OP_RLDUB: case DIF_OP_RLDUH: case DIF_OP_RLDUW: case DIF_OP_RLDX: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_ULDSB: case DIF_OP_ULDSH: case DIF_OP_ULDSW: case DIF_OP_ULDUB: case DIF_OP_ULDUH: case DIF_OP_ULDUW: case DIF_OP_ULDX: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_STB: case DIF_OP_STH: case DIF_OP_STW: case DIF_OP_STX: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to 0 address\n"); break; case DIF_OP_CMP: case DIF_OP_SCMP: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 >= nregs) err += efunc(pc, "invalid register %u\n", r2); if (rd != 0) err += efunc(pc, "non-zero reserved bits\n"); break; case DIF_OP_TST: if (r1 >= nregs) err += efunc(pc, "invalid register %u\n", r1); if (r2 != 0 || rd != 0) err += efunc(pc, "non-zero reserved bits\n"); break; case DIF_OP_BA: case DIF_OP_BE: case DIF_OP_BNE: case DIF_OP_BG: case DIF_OP_BGU: case DIF_OP_BGE: case DIF_OP_BGEU: case DIF_OP_BL: case DIF_OP_BLU: case DIF_OP_BLE: case DIF_OP_BLEU: if (label >= dp->dtdo_len) { err += efunc(pc, "invalid branch target %u\n", label); } if (label <= pc) { err += efunc(pc, "backward branch to %u\n", label); } break; case DIF_OP_RET: if (r1 != 0 || r2 != 0) err += efunc(pc, "non-zero reserved bits\n"); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); break; case DIF_OP_NOP: case DIF_OP_POPTS: case DIF_OP_FLUSHTS: if (r1 != 0 || r2 != 0 || rd != 0) err += efunc(pc, "non-zero reserved bits\n"); break; case DIF_OP_SETX: if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) { err += efunc(pc, "invalid integer ref %u\n", DIF_INSTR_INTEGER(instr)); } if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_SETS: if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) { err += efunc(pc, "invalid string ref %u\n", DIF_INSTR_STRING(instr)); } if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_LDGA: case DIF_OP_LDTA: if (r1 > DIF_VAR_ARRAY_MAX) err += efunc(pc, "invalid array %u\n", r1); if (r2 >= nregs) err += efunc(pc, "invalid register %u\n", r2); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_LDGS: case DIF_OP_LDTS: case DIF_OP_LDLS: case DIF_OP_LDGAA: case DIF_OP_LDTAA: if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX) err += efunc(pc, "invalid variable %u\n", v); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); break; case DIF_OP_STGS: case DIF_OP_STTS: case DIF_OP_STLS: case DIF_OP_STGAA: case DIF_OP_STTAA: if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX) err += efunc(pc, "invalid variable %u\n", v); if (rs >= nregs) err += efunc(pc, "invalid register %u\n", rd); break; case DIF_OP_CALL: if (subr > DIF_SUBR_MAX) err += efunc(pc, "invalid subr %u\n", subr); if (rd >= nregs) err += efunc(pc, "invalid register %u\n", rd); if (rd == 0) err += efunc(pc, "cannot write to %r0\n"); if (subr == DIF_SUBR_COPYOUT || subr == DIF_SUBR_COPYOUTSTR) { dp->dtdo_destructive = 1; } break; case DIF_OP_PUSHTR: if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF) err += efunc(pc, "invalid ref type %u\n", type); if (r2 >= nregs) err += efunc(pc, "invalid register %u\n", r2); if (rs >= nregs) err += efunc(pc, "invalid register %u\n", rs); break; case DIF_OP_PUSHTV: if (type != DIF_TYPE_CTF) err += efunc(pc, "invalid val type %u\n", type); if (r2 >= nregs) err += efunc(pc, "invalid register %u\n", r2); if (rs >= nregs) err += efunc(pc, "invalid register %u\n", rs); break; default: err += efunc(pc, "invalid opcode %u\n", DIF_INSTR_OP(instr)); } } if (dp->dtdo_len != 0 && DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) { err += efunc(dp->dtdo_len - 1, "expected 'ret' as last DIF instruction\n"); } if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) { /* * If we're not returning by reference, the size must be either * 0 or the size of one of the base types. */ switch (dp->dtdo_rtype.dtdt_size) { case 0: case sizeof (uint8_t): case sizeof (uint16_t): case sizeof (uint32_t): case sizeof (uint64_t): break; default: err += efunc(dp->dtdo_len - 1, "bad return size\n"); } } for (i = 0; i < dp->dtdo_varlen && err == 0; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL; dtrace_diftype_t *vt, *et; uint_t id; int ndx; if (v->dtdv_scope != DIFV_SCOPE_GLOBAL && v->dtdv_scope != DIFV_SCOPE_THREAD && v->dtdv_scope != DIFV_SCOPE_LOCAL) { err += efunc(i, "unrecognized variable scope %d\n", v->dtdv_scope); break; } if (v->dtdv_kind != DIFV_KIND_ARRAY && v->dtdv_kind != DIFV_KIND_SCALAR) { err += efunc(i, "unrecognized variable type %d\n", v->dtdv_kind); break; } if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) { err += efunc(i, "%d exceeds variable id limit\n", id); break; } if (id < DIF_VAR_OTHER_UBASE) continue; /* * For user-defined variables, we need to check that this * definition is identical to any previous definition that we * encountered. */ ndx = id - DIF_VAR_OTHER_UBASE; switch (v->dtdv_scope) { case DIFV_SCOPE_GLOBAL: if (ndx < vstate->dtvs_nglobals) { dtrace_statvar_t *svar; if ((svar = vstate->dtvs_globals[ndx]) != NULL) existing = &svar->dtsv_var; } break; case DIFV_SCOPE_THREAD: if (ndx < vstate->dtvs_ntlocals) existing = &vstate->dtvs_tlocals[ndx]; break; case DIFV_SCOPE_LOCAL: if (ndx < vstate->dtvs_nlocals) { dtrace_statvar_t *svar; if ((svar = vstate->dtvs_locals[ndx]) != NULL) existing = &svar->dtsv_var; } break; } vt = &v->dtdv_type; if (vt->dtdt_flags & DIF_TF_BYREF) { if (vt->dtdt_size == 0) { err += efunc(i, "zero-sized variable\n"); break; } if (v->dtdv_scope == DIFV_SCOPE_GLOBAL && vt->dtdt_size > dtrace_global_maxsize) { err += efunc(i, "oversized by-ref global\n"); break; } } if (existing == NULL || existing->dtdv_id == 0) continue; ASSERT(existing->dtdv_id == v->dtdv_id); ASSERT(existing->dtdv_scope == v->dtdv_scope); if (existing->dtdv_kind != v->dtdv_kind) err += efunc(i, "%d changed variable kind\n", id); et = &existing->dtdv_type; if (vt->dtdt_flags != et->dtdt_flags) { err += efunc(i, "%d changed variable type flags\n", id); break; } if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) { err += efunc(i, "%d changed variable type size\n", id); break; } } return (err); } /* * Validate a DTrace DIF object that it is to be used as a helper. Helpers * are much more constrained than normal DIFOs. Specifically, they may * not: * * 1. Make calls to subroutines other than copyin(), copyinstr() or * miscellaneous string routines * 2. Access DTrace variables other than the args[] array, and the * curthread, pid, ppid, tid, execname, zonename, uid and gid variables. * 3. Have thread-local variables. * 4. Have dynamic variables. */ static int dtrace_difo_validate_helper(dtrace_difo_t *dp) { int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err; int err = 0; uint_t pc; for (pc = 0; pc < dp->dtdo_len; pc++) { dif_instr_t instr = dp->dtdo_buf[pc]; uint_t v = DIF_INSTR_VAR(instr); uint_t subr = DIF_INSTR_SUBR(instr); uint_t op = DIF_INSTR_OP(instr); switch (op) { case DIF_OP_OR: case DIF_OP_XOR: case DIF_OP_AND: case DIF_OP_SLL: case DIF_OP_SRL: case DIF_OP_SRA: case DIF_OP_SUB: case DIF_OP_ADD: case DIF_OP_MUL: case DIF_OP_SDIV: case DIF_OP_UDIV: case DIF_OP_SREM: case DIF_OP_UREM: case DIF_OP_COPYS: case DIF_OP_NOT: case DIF_OP_MOV: case DIF_OP_RLDSB: case DIF_OP_RLDSH: case DIF_OP_RLDSW: case DIF_OP_RLDUB: case DIF_OP_RLDUH: case DIF_OP_RLDUW: case DIF_OP_RLDX: case DIF_OP_ULDSB: case DIF_OP_ULDSH: case DIF_OP_ULDSW: case DIF_OP_ULDUB: case DIF_OP_ULDUH: case DIF_OP_ULDUW: case DIF_OP_ULDX: case DIF_OP_STB: case DIF_OP_STH: case DIF_OP_STW: case DIF_OP_STX: case DIF_OP_ALLOCS: case DIF_OP_CMP: case DIF_OP_SCMP: case DIF_OP_TST: case DIF_OP_BA: case DIF_OP_BE: case DIF_OP_BNE: case DIF_OP_BG: case DIF_OP_BGU: case DIF_OP_BGE: case DIF_OP_BGEU: case DIF_OP_BL: case DIF_OP_BLU: case DIF_OP_BLE: case DIF_OP_BLEU: case DIF_OP_RET: case DIF_OP_NOP: case DIF_OP_POPTS: case DIF_OP_FLUSHTS: case DIF_OP_SETX: case DIF_OP_SETS: case DIF_OP_LDGA: case DIF_OP_LDLS: case DIF_OP_STGS: case DIF_OP_STLS: case DIF_OP_PUSHTR: case DIF_OP_PUSHTV: break; case DIF_OP_LDGS: if (v >= DIF_VAR_OTHER_UBASE) break; if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) break; if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID || v == DIF_VAR_PPID || v == DIF_VAR_TID || v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME || v == DIF_VAR_UID || v == DIF_VAR_GID) break; err += efunc(pc, "illegal variable %u\n", v); break; case DIF_OP_LDTA: case DIF_OP_LDTS: case DIF_OP_LDGAA: case DIF_OP_LDTAA: err += efunc(pc, "illegal dynamic variable load\n"); break; case DIF_OP_STTS: case DIF_OP_STGAA: case DIF_OP_STTAA: err += efunc(pc, "illegal dynamic variable store\n"); break; case DIF_OP_CALL: if (subr == DIF_SUBR_ALLOCA || subr == DIF_SUBR_BCOPY || subr == DIF_SUBR_COPYIN || subr == DIF_SUBR_COPYINTO || subr == DIF_SUBR_COPYINSTR || subr == DIF_SUBR_INDEX || subr == DIF_SUBR_INET_NTOA || subr == DIF_SUBR_INET_NTOA6 || subr == DIF_SUBR_INET_NTOP || subr == DIF_SUBR_LLTOSTR || subr == DIF_SUBR_RINDEX || subr == DIF_SUBR_STRCHR || subr == DIF_SUBR_STRJOIN || subr == DIF_SUBR_STRRCHR || subr == DIF_SUBR_STRSTR || subr == DIF_SUBR_COREPROFILE || subr == DIF_SUBR_HTONS || subr == DIF_SUBR_HTONL || subr == DIF_SUBR_HTONLL || subr == DIF_SUBR_NTOHS || subr == DIF_SUBR_NTOHL || subr == DIF_SUBR_NTOHLL) break; err += efunc(pc, "invalid subr %u\n", subr); break; default: err += efunc(pc, "invalid opcode %u\n", DIF_INSTR_OP(instr)); } } return (err); } /* * Returns 1 if the expression in the DIF object can be cached on a per-thread * basis; 0 if not. */ static int dtrace_difo_cacheable(dtrace_difo_t *dp) { uint_t i; if (dp == NULL) return (0); for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; if (v->dtdv_scope != DIFV_SCOPE_GLOBAL) continue; switch (v->dtdv_id) { case DIF_VAR_CURTHREAD: case DIF_VAR_PID: case DIF_VAR_TID: case DIF_VAR_EXECNAME: case DIF_VAR_ZONENAME: break; default: return (0); } } /* * This DIF object may be cacheable. Now we need to look for any * array loading instructions, any memory loading instructions, or * any stores to thread-local variables. */ for (i = 0; i < dp->dtdo_len; i++) { uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]); if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) || (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) || (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) || op == DIF_OP_LDGA || op == DIF_OP_STTS) return (0); } return (1); } static void dtrace_difo_hold(dtrace_difo_t *dp) { uint_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); dp->dtdo_refcnt++; ASSERT(dp->dtdo_refcnt != 0); /* * We need to check this DIF object for references to the variable * DIF_VAR_VTIMESTAMP. */ for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; if (v->dtdv_id != DIF_VAR_VTIMESTAMP) continue; if (dtrace_vtime_references++ == 0) dtrace_vtime_enable(); } } /* * This routine calculates the dynamic variable chunksize for a given DIF * object. The calculation is not fool-proof, and can probably be tricked by * malicious DIF -- but it works for all compiler-generated DIF. Because this * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail * if a dynamic variable size exceeds the chunksize. */ static void dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate) { uint64_t sval = 0; dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */ const dif_instr_t *text = dp->dtdo_buf; uint_t pc, srd = 0; uint_t ttop = 0; size_t size, ksize; uint_t id, i; for (pc = 0; pc < dp->dtdo_len; pc++) { dif_instr_t instr = text[pc]; uint_t op = DIF_INSTR_OP(instr); uint_t rd = DIF_INSTR_RD(instr); uint_t r1 = DIF_INSTR_R1(instr); uint_t nkeys = 0; uchar_t scope; dtrace_key_t *key = tupregs; switch (op) { case DIF_OP_SETX: sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)]; srd = rd; continue; case DIF_OP_STTS: key = &tupregs[DIF_DTR_NREGS]; key[0].dttk_size = 0; key[1].dttk_size = 0; nkeys = 2; scope = DIFV_SCOPE_THREAD; break; case DIF_OP_STGAA: case DIF_OP_STTAA: nkeys = ttop; if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) key[nkeys++].dttk_size = 0; key[nkeys++].dttk_size = 0; if (op == DIF_OP_STTAA) { scope = DIFV_SCOPE_THREAD; } else { scope = DIFV_SCOPE_GLOBAL; } break; case DIF_OP_PUSHTR: if (ttop == DIF_DTR_NREGS) return; if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) { /* * If the register for the size of the "pushtr" * is %r0 (or the value is 0) and the type is * a string, we'll use the system-wide default * string size. */ tupregs[ttop++].dttk_size = dtrace_strsize_default; } else { if (srd == 0) return; tupregs[ttop++].dttk_size = sval; } break; case DIF_OP_PUSHTV: if (ttop == DIF_DTR_NREGS) return; tupregs[ttop++].dttk_size = 0; break; case DIF_OP_FLUSHTS: ttop = 0; break; case DIF_OP_POPTS: if (ttop != 0) ttop--; break; } sval = 0; srd = 0; if (nkeys == 0) continue; /* * We have a dynamic variable allocation; calculate its size. */ for (ksize = 0, i = 0; i < nkeys; i++) ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t)); size = sizeof (dtrace_dynvar_t); size += sizeof (dtrace_key_t) * (nkeys - 1); size += ksize; /* * Now we need to determine the size of the stored data. */ id = DIF_INSTR_VAR(instr); for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; if (v->dtdv_id == id && v->dtdv_scope == scope) { size += v->dtdv_type.dtdt_size; break; } } if (i == dp->dtdo_varlen) return; /* * We have the size. If this is larger than the chunk size * for our dynamic variable state, reset the chunk size. */ size = P2ROUNDUP(size, sizeof (uint64_t)); if (size > vstate->dtvs_dynvars.dtds_chunksize) vstate->dtvs_dynvars.dtds_chunksize = size; } } static void dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate) { int oldsvars, osz, nsz, otlocals, ntlocals; uint_t i, id; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0); for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; dtrace_statvar_t *svar; dtrace_statvar_t ***svarp = NULL; size_t dsize = 0; uint8_t scope = v->dtdv_scope; int *np = (int *)NULL; if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE) continue; id -= DIF_VAR_OTHER_UBASE; switch (scope) { case DIFV_SCOPE_THREAD: while (id >= (uint_t)(otlocals = vstate->dtvs_ntlocals)) { dtrace_difv_t *tlocals; if ((ntlocals = (otlocals << 1)) == 0) ntlocals = 1; osz = otlocals * sizeof (dtrace_difv_t); nsz = ntlocals * sizeof (dtrace_difv_t); tlocals = kmem_zalloc(nsz, KM_SLEEP); if (osz != 0) { bcopy(vstate->dtvs_tlocals, tlocals, osz); kmem_free(vstate->dtvs_tlocals, osz); } vstate->dtvs_tlocals = tlocals; vstate->dtvs_ntlocals = ntlocals; } vstate->dtvs_tlocals[id] = *v; continue; case DIFV_SCOPE_LOCAL: np = &vstate->dtvs_nlocals; svarp = &vstate->dtvs_locals; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) dsize = (int)NCPU * (v->dtdv_type.dtdt_size + sizeof (uint64_t)); else dsize = (int)NCPU * sizeof (uint64_t); break; case DIFV_SCOPE_GLOBAL: np = &vstate->dtvs_nglobals; svarp = &vstate->dtvs_globals; if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) dsize = v->dtdv_type.dtdt_size + sizeof (uint64_t); break; default: ASSERT(0); } while (id >= (uint_t)(oldsvars = *np)) { dtrace_statvar_t **statics; int newsvars, oldsize, newsize; if ((newsvars = (oldsvars << 1)) == 0) newsvars = 1; oldsize = oldsvars * sizeof (dtrace_statvar_t *); newsize = newsvars * sizeof (dtrace_statvar_t *); statics = kmem_zalloc(newsize, KM_SLEEP); if (oldsize != 0) { bcopy(*svarp, statics, oldsize); kmem_free(*svarp, oldsize); } *svarp = statics; *np = newsvars; } if ((svar = (*svarp)[id]) == NULL) { svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP); svar->dtsv_var = *v; if ((svar->dtsv_size = dsize) != 0) { svar->dtsv_data = (uint64_t)(uintptr_t) kmem_zalloc(dsize, KM_SLEEP); } (*svarp)[id] = svar; } svar->dtsv_refcnt++; } dtrace_difo_chunksize(dp, vstate); dtrace_difo_hold(dp); } static dtrace_difo_t * dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate) { dtrace_difo_t *new; size_t sz; ASSERT(dp->dtdo_buf != NULL); ASSERT(dp->dtdo_refcnt != 0); new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP); ASSERT(dp->dtdo_buf != NULL); sz = dp->dtdo_len * sizeof (dif_instr_t); new->dtdo_buf = kmem_alloc(sz, KM_SLEEP); bcopy(dp->dtdo_buf, new->dtdo_buf, sz); new->dtdo_len = dp->dtdo_len; if (dp->dtdo_strtab != NULL) { ASSERT(dp->dtdo_strlen != 0); new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP); bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen); new->dtdo_strlen = dp->dtdo_strlen; } if (dp->dtdo_inttab != NULL) { ASSERT(dp->dtdo_intlen != 0); sz = dp->dtdo_intlen * sizeof (uint64_t); new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP); bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz); new->dtdo_intlen = dp->dtdo_intlen; } if (dp->dtdo_vartab != NULL) { ASSERT(dp->dtdo_varlen != 0); sz = dp->dtdo_varlen * sizeof (dtrace_difv_t); new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP); bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz); new->dtdo_varlen = dp->dtdo_varlen; } dtrace_difo_init(new, vstate); return (new); } static void dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate) { uint_t i; ASSERT(dp->dtdo_refcnt == 0); for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; dtrace_statvar_t *svar; dtrace_statvar_t **svarp = NULL; uint_t id; uint8_t scope = v->dtdv_scope; int *np = NULL; switch (scope) { case DIFV_SCOPE_THREAD: continue; case DIFV_SCOPE_LOCAL: np = &vstate->dtvs_nlocals; svarp = vstate->dtvs_locals; break; case DIFV_SCOPE_GLOBAL: np = &vstate->dtvs_nglobals; svarp = vstate->dtvs_globals; break; default: ASSERT(0); } if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE) continue; id -= DIF_VAR_OTHER_UBASE; ASSERT(id < (uint_t)*np); svar = svarp[id]; ASSERT(svar != NULL); ASSERT(svar->dtsv_refcnt > 0); if (--svar->dtsv_refcnt > 0) continue; if (svar->dtsv_size != 0) { ASSERT(svar->dtsv_data != 0); kmem_free((void *)(uintptr_t)svar->dtsv_data, svar->dtsv_size); } kmem_free(svar, sizeof (dtrace_statvar_t)); svarp[id] = NULL; } kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t)); kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t)); kmem_free(dp->dtdo_strtab, dp->dtdo_strlen); kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t)); kmem_free(dp, sizeof (dtrace_difo_t)); } static void dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate) { uint_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dp->dtdo_refcnt != 0); for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; if (v->dtdv_id != DIF_VAR_VTIMESTAMP) continue; ASSERT(dtrace_vtime_references > 0); if (--dtrace_vtime_references == 0) dtrace_vtime_disable(); } if (--dp->dtdo_refcnt == 0) dtrace_difo_destroy(dp, vstate); } /* * DTrace Format Functions */ static uint16_t dtrace_format_add(dtrace_state_t *state, char *str) { char *fmt, **new; uint16_t ndx, len = strlen(str) + 1; fmt = kmem_zalloc(len, KM_SLEEP); bcopy(str, fmt, len); for (ndx = 0; ndx < state->dts_nformats; ndx++) { if (state->dts_formats[ndx] == NULL) { state->dts_formats[ndx] = fmt; return (ndx + 1); } } if (state->dts_nformats == USHRT_MAX) { /* * This is only likely if a denial-of-service attack is being * attempted. As such, it's okay to fail silently here. */ kmem_free(fmt, len); return (0); } /* * For simplicity, we always resize the formats array to be exactly the * number of formats. */ ndx = state->dts_nformats++; new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP); if (state->dts_formats != NULL) { ASSERT(ndx != 0); bcopy(state->dts_formats, new, ndx * sizeof (char *)); kmem_free(state->dts_formats, ndx * sizeof (char *)); } state->dts_formats = new; state->dts_formats[ndx] = fmt; return (ndx + 1); } static void dtrace_format_remove(dtrace_state_t *state, uint16_t format) { char *fmt; ASSERT(state->dts_formats != NULL); ASSERT(format <= state->dts_nformats); ASSERT(state->dts_formats[format - 1] != NULL); fmt = state->dts_formats[format - 1]; kmem_free(fmt, strlen(fmt) + 1); state->dts_formats[format - 1] = NULL; } static void dtrace_format_destroy(dtrace_state_t *state) { int i; if (state->dts_nformats == 0) { ASSERT(state->dts_formats == NULL); return; } ASSERT(state->dts_formats != NULL); for (i = 0; i < state->dts_nformats; i++) { char *fmt = state->dts_formats[i]; if (fmt == NULL) continue; kmem_free(fmt, strlen(fmt) + 1); } kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *)); state->dts_nformats = 0; state->dts_formats = NULL; } /* * DTrace Predicate Functions */ static dtrace_predicate_t * dtrace_predicate_create(dtrace_difo_t *dp) { dtrace_predicate_t *pred; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dp->dtdo_refcnt != 0); pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP); pred->dtp_difo = dp; pred->dtp_refcnt = 1; if (!dtrace_difo_cacheable(dp)) return (pred); if (dtrace_predcache_id == DTRACE_CACHEIDNONE) { /* * This is only theoretically possible -- we have had 2^32 * cacheable predicates on this machine. We cannot allow any * more predicates to become cacheable: as unlikely as it is, * there may be a thread caching a (now stale) predicate cache * ID. (N.B.: the temptation is being successfully resisted to * have this cmn_err() "Holy shit -- we executed this code!") */ return (pred); } pred->dtp_cacheid = dtrace_predcache_id++; return (pred); } static void dtrace_predicate_hold(dtrace_predicate_t *pred) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0); ASSERT(pred->dtp_refcnt > 0); pred->dtp_refcnt++; } static void dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate) { dtrace_difo_t *dp = pred->dtp_difo; #pragma unused(dp) /* __APPLE__ */ lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dp != NULL && dp->dtdo_refcnt != 0); ASSERT(pred->dtp_refcnt > 0); if (--pred->dtp_refcnt == 0) { dtrace_difo_release(pred->dtp_difo, vstate); kmem_free(pred, sizeof (dtrace_predicate_t)); } } /* * DTrace Action Description Functions */ static dtrace_actdesc_t * dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple, uint64_t uarg, uint64_t arg) { dtrace_actdesc_t *act; ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != 0 && arg >= KERNELBASE) || (arg == 0 && kind == DTRACEACT_PRINTA)); act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP); act->dtad_kind = kind; act->dtad_ntuple = ntuple; act->dtad_uarg = uarg; act->dtad_arg = arg; act->dtad_refcnt = 1; return (act); } static void dtrace_actdesc_hold(dtrace_actdesc_t *act) { ASSERT(act->dtad_refcnt >= 1); act->dtad_refcnt++; } static void dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate) { dtrace_actkind_t kind = act->dtad_kind; dtrace_difo_t *dp; ASSERT(act->dtad_refcnt >= 1); if (--act->dtad_refcnt != 0) return; if ((dp = act->dtad_difo) != NULL) dtrace_difo_release(dp, vstate); if (DTRACEACT_ISPRINTFLIKE(kind)) { char *str = (char *)(uintptr_t)act->dtad_arg; ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) || (str == NULL && act->dtad_kind == DTRACEACT_PRINTA)); if (str != NULL) kmem_free(str, strlen(str) + 1); } kmem_free(act, sizeof (dtrace_actdesc_t)); } /* * DTrace ECB Functions */ static dtrace_ecb_t * dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe) { dtrace_ecb_t *ecb; dtrace_epid_t epid; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP); ecb->dte_predicate = NULL; ecb->dte_probe = probe; /* * The default size is the size of the default action: recording * the epid. */ ecb->dte_size = ecb->dte_needed = sizeof (dtrace_epid_t); ecb->dte_alignment = sizeof (dtrace_epid_t); epid = state->dts_epid++; if (epid - 1 >= (dtrace_epid_t)state->dts_necbs) { dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs; int necbs = state->dts_necbs << 1; ASSERT(epid == (dtrace_epid_t)state->dts_necbs + 1); if (necbs == 0) { ASSERT(oecbs == NULL); necbs = 1; } ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP); if (oecbs != NULL) bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs)); dtrace_membar_producer(); state->dts_ecbs = ecbs; if (oecbs != NULL) { /* * If this state is active, we must dtrace_sync() * before we can free the old dts_ecbs array: we're * coming in hot, and there may be active ring * buffer processing (which indexes into the dts_ecbs * array) on another CPU. */ if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) dtrace_sync(); kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs)); } dtrace_membar_producer(); state->dts_necbs = necbs; } ecb->dte_state = state; ASSERT(state->dts_ecbs[epid - 1] == NULL); dtrace_membar_producer(); state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb; return (ecb); } static int dtrace_ecb_enable(dtrace_ecb_t *ecb) { dtrace_probe_t *probe = ecb->dte_probe; lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(ecb->dte_next == NULL); if (probe == NULL) { /* * This is the NULL probe -- there's nothing to do. */ return(0); } probe->dtpr_provider->dtpv_ecb_count++; if (probe->dtpr_ecb == NULL) { dtrace_provider_t *prov = probe->dtpr_provider; /* * We're the first ECB on this probe. */ probe->dtpr_ecb = probe->dtpr_ecb_last = ecb; if (ecb->dte_predicate != NULL) probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid; return (prov->dtpv_pops.dtps_enable(prov->dtpv_arg, probe->dtpr_id, probe->dtpr_arg)); } else { /* * This probe is already active. Swing the last pointer to * point to the new ECB, and issue a dtrace_sync() to assure * that all CPUs have seen the change. */ ASSERT(probe->dtpr_ecb_last != NULL); probe->dtpr_ecb_last->dte_next = ecb; probe->dtpr_ecb_last = ecb; probe->dtpr_predcache = 0; dtrace_sync(); return(0); } } static void dtrace_ecb_resize(dtrace_ecb_t *ecb) { uint32_t maxalign = sizeof (dtrace_epid_t); uint32_t align = sizeof (uint8_t), offs, diff; dtrace_action_t *act; int wastuple = 0; uint32_t aggbase = UINT32_MAX; dtrace_state_t *state = ecb->dte_state; /* * If we record anything, we always record the epid. (And we always * record it first.) */ offs = sizeof (dtrace_epid_t); ecb->dte_size = ecb->dte_needed = sizeof (dtrace_epid_t); for (act = ecb->dte_action; act != NULL; act = act->dta_next) { dtrace_recdesc_t *rec = &act->dta_rec; if ((align = rec->dtrd_alignment) > maxalign) maxalign = align; if (!wastuple && act->dta_intuple) { /* * This is the first record in a tuple. Align the * offset to be at offset 4 in an 8-byte aligned * block. */ diff = offs + sizeof (dtrace_aggid_t); if ((diff = (diff & (sizeof (uint64_t) - 1)))) offs += sizeof (uint64_t) - diff; aggbase = offs - sizeof (dtrace_aggid_t); ASSERT(!(aggbase & (sizeof (uint64_t) - 1))); } /*LINTED*/ if (rec->dtrd_size != 0 && (diff = (offs & (align - 1)))) { /* * The current offset is not properly aligned; align it. */ offs += align - diff; } rec->dtrd_offset = offs; if (offs + rec->dtrd_size > ecb->dte_needed) { ecb->dte_needed = offs + rec->dtrd_size; if (ecb->dte_needed > state->dts_needed) state->dts_needed = ecb->dte_needed; } if (DTRACEACT_ISAGG(act->dta_kind)) { dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act; dtrace_action_t *first = agg->dtag_first, *prev; ASSERT(rec->dtrd_size != 0 && first != NULL); ASSERT(wastuple); ASSERT(aggbase != UINT32_MAX); agg->dtag_base = aggbase; while ((prev = first->dta_prev) != NULL && DTRACEACT_ISAGG(prev->dta_kind)) { agg = (dtrace_aggregation_t *)prev; first = agg->dtag_first; } if (prev != NULL) { offs = prev->dta_rec.dtrd_offset + prev->dta_rec.dtrd_size; } else { offs = sizeof (dtrace_epid_t); } wastuple = 0; } else { if (!act->dta_intuple) ecb->dte_size = offs + rec->dtrd_size; offs += rec->dtrd_size; } wastuple = act->dta_intuple; } if ((act = ecb->dte_action) != NULL && !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) && ecb->dte_size == sizeof (dtrace_epid_t)) { /* * If the size is still sizeof (dtrace_epid_t), then all * actions store no data; set the size to 0. */ ecb->dte_alignment = maxalign; ecb->dte_size = 0; /* * If the needed space is still sizeof (dtrace_epid_t), then * all actions need no additional space; set the needed * size to 0. */ if (ecb->dte_needed == sizeof (dtrace_epid_t)) ecb->dte_needed = 0; return; } /* * Set our alignment, and make sure that the dte_size and dte_needed * are aligned to the size of an EPID. */ ecb->dte_alignment = maxalign; ecb->dte_size = (ecb->dte_size + (sizeof (dtrace_epid_t) - 1)) & ~(sizeof (dtrace_epid_t) - 1); ecb->dte_needed = (ecb->dte_needed + (sizeof (dtrace_epid_t) - 1)) & ~(sizeof (dtrace_epid_t) - 1); ASSERT(ecb->dte_size <= ecb->dte_needed); } static dtrace_action_t * dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc) { dtrace_aggregation_t *agg; size_t size = sizeof (uint64_t); int ntuple = desc->dtad_ntuple; dtrace_action_t *act; dtrace_recdesc_t *frec; dtrace_aggid_t aggid; dtrace_state_t *state = ecb->dte_state; agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP); agg->dtag_ecb = ecb; ASSERT(DTRACEACT_ISAGG(desc->dtad_kind)); switch (desc->dtad_kind) { case DTRACEAGG_MIN: agg->dtag_initial = INT64_MAX; agg->dtag_aggregate = dtrace_aggregate_min; break; case DTRACEAGG_MAX: agg->dtag_initial = INT64_MIN; agg->dtag_aggregate = dtrace_aggregate_max; break; case DTRACEAGG_COUNT: agg->dtag_aggregate = dtrace_aggregate_count; break; case DTRACEAGG_QUANTIZE: agg->dtag_aggregate = dtrace_aggregate_quantize; size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) * sizeof (uint64_t); break; case DTRACEAGG_LQUANTIZE: { uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg); uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg); agg->dtag_initial = desc->dtad_arg; agg->dtag_aggregate = dtrace_aggregate_lquantize; if (step == 0 || levels == 0) goto err; size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t); break; } case DTRACEAGG_LLQUANTIZE: { uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg); uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg); uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg); uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg); int64_t v; agg->dtag_initial = desc->dtad_arg; agg->dtag_aggregate = dtrace_aggregate_llquantize; if (factor < 2 || low >= high || nsteps < factor) goto err; /* * Now check that the number of steps evenly divides a power * of the factor. (This assures both integer bucket size and * linearity within each magnitude.) */ for (v = factor; v < nsteps; v *= factor) continue; if ((v % nsteps) || (nsteps % factor)) goto err; size = (dtrace_aggregate_llquantize_bucket(factor, low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t); break; } case DTRACEAGG_AVG: agg->dtag_aggregate = dtrace_aggregate_avg; size = sizeof (uint64_t) * 2; break; case DTRACEAGG_STDDEV: agg->dtag_aggregate = dtrace_aggregate_stddev; size = sizeof (uint64_t) * 4; break; case DTRACEAGG_SUM: agg->dtag_aggregate = dtrace_aggregate_sum; break; default: goto err; } agg->dtag_action.dta_rec.dtrd_size = size; if (ntuple == 0) goto err; /* * We must make sure that we have enough actions for the n-tuple. */ for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) { if (DTRACEACT_ISAGG(act->dta_kind)) break; if (--ntuple == 0) { /* * This is the action with which our n-tuple begins. */ agg->dtag_first = act; goto success; } } /* * This n-tuple is short by ntuple elements. Return failure. */ ASSERT(ntuple != 0); err: kmem_free(agg, sizeof (dtrace_aggregation_t)); return (NULL); success: /* * If the last action in the tuple has a size of zero, it's actually * an expression argument for the aggregating action. */ ASSERT(ecb->dte_action_last != NULL); act = ecb->dte_action_last; if (act->dta_kind == DTRACEACT_DIFEXPR) { ASSERT(act->dta_difo != NULL); if (act->dta_difo->dtdo_rtype.dtdt_size == 0) agg->dtag_hasarg = 1; } /* * We need to allocate an id for this aggregation. */ aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1, VM_BESTFIT | VM_SLEEP); if (aggid - 1 >= (dtrace_aggid_t)state->dts_naggregations) { dtrace_aggregation_t **oaggs = state->dts_aggregations; dtrace_aggregation_t **aggs; int naggs = state->dts_naggregations << 1; int onaggs = state->dts_naggregations; ASSERT(aggid == (dtrace_aggid_t)state->dts_naggregations + 1); if (naggs == 0) { ASSERT(oaggs == NULL); naggs = 1; } aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP); if (oaggs != NULL) { bcopy(oaggs, aggs, onaggs * sizeof (*aggs)); kmem_free(oaggs, onaggs * sizeof (*aggs)); } state->dts_aggregations = aggs; state->dts_naggregations = naggs; } ASSERT(state->dts_aggregations[aggid - 1] == NULL); state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg; frec = &agg->dtag_first->dta_rec; if (frec->dtrd_alignment < sizeof (dtrace_aggid_t)) frec->dtrd_alignment = sizeof (dtrace_aggid_t); for (act = agg->dtag_first; act != NULL; act = act->dta_next) { ASSERT(!act->dta_intuple); act->dta_intuple = 1; } return (&agg->dtag_action); } static void dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act) { dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act; dtrace_state_t *state = ecb->dte_state; dtrace_aggid_t aggid = agg->dtag_id; ASSERT(DTRACEACT_ISAGG(act->dta_kind)); vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1); ASSERT(state->dts_aggregations[aggid - 1] == agg); state->dts_aggregations[aggid - 1] = NULL; kmem_free(agg, sizeof (dtrace_aggregation_t)); } static int dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc) { dtrace_action_t *action, *last; dtrace_difo_t *dp = desc->dtad_difo; uint32_t size = 0, align = sizeof (uint8_t), mask; uint16_t format = 0; dtrace_recdesc_t *rec; dtrace_state_t *state = ecb->dte_state; dtrace_optval_t *opt = state->dts_options; dtrace_optval_t nframes=0, strsize; uint64_t arg = desc->dtad_arg; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1); if (DTRACEACT_ISAGG(desc->dtad_kind)) { /* * If this is an aggregating action, there must be neither * a speculate nor a commit on the action chain. */ dtrace_action_t *act; for (act = ecb->dte_action; act != NULL; act = act->dta_next) { if (act->dta_kind == DTRACEACT_COMMIT) return (EINVAL); if (act->dta_kind == DTRACEACT_SPECULATE) return (EINVAL); } action = dtrace_ecb_aggregation_create(ecb, desc); if (action == NULL) return (EINVAL); } else { if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) || (desc->dtad_kind == DTRACEACT_DIFEXPR && dp != NULL && dp->dtdo_destructive)) { state->dts_destructive = 1; } switch (desc->dtad_kind) { case DTRACEACT_PRINTF: case DTRACEACT_PRINTA: case DTRACEACT_SYSTEM: case DTRACEACT_FREOPEN: /* * We know that our arg is a string -- turn it into a * format. */ if (arg == 0) { ASSERT(desc->dtad_kind == DTRACEACT_PRINTA); format = 0; } else { ASSERT(arg != 0); ASSERT(arg > KERNELBASE); format = dtrace_format_add(state, (char *)(uintptr_t)arg); } /*FALLTHROUGH*/ case DTRACEACT_LIBACT: case DTRACEACT_DIFEXPR: case DTRACEACT_TRACEMEM: case DTRACEACT_TRACEMEM_DYNSIZE: case DTRACEACT_APPLEBINARY: /* __APPLE__ */ if (dp == NULL) return (EINVAL); if ((size = dp->dtdo_rtype.dtdt_size) != 0) break; if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) { if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) return (EINVAL); size = opt[DTRACEOPT_STRSIZE]; } break; case DTRACEACT_STACK: if ((nframes = arg) == 0) { nframes = opt[DTRACEOPT_STACKFRAMES]; ASSERT(nframes > 0); arg = nframes; } size = nframes * sizeof (pc_t); break; case DTRACEACT_JSTACK: if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0) strsize = opt[DTRACEOPT_JSTACKSTRSIZE]; if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) nframes = opt[DTRACEOPT_JSTACKFRAMES]; arg = DTRACE_USTACK_ARG(nframes, strsize); /*FALLTHROUGH*/ case DTRACEACT_USTACK: if (desc->dtad_kind != DTRACEACT_JSTACK && (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) { strsize = DTRACE_USTACK_STRSIZE(arg); nframes = opt[DTRACEOPT_USTACKFRAMES]; ASSERT(nframes > 0); arg = DTRACE_USTACK_ARG(nframes, strsize); } /* * Save a slot for the pid. */ size = (nframes + 1) * sizeof (uint64_t); size += DTRACE_USTACK_STRSIZE(arg); size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t))); break; case DTRACEACT_SYM: case DTRACEACT_MOD: if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) != sizeof (uint64_t)) || (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) return (EINVAL); break; case DTRACEACT_USYM: case DTRACEACT_UMOD: case DTRACEACT_UADDR: if (dp == NULL || (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) || (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) return (EINVAL); /* * We have a slot for the pid, plus a slot for the * argument. To keep things simple (aligned with * bitness-neutral sizing), we store each as a 64-bit * quantity. */ size = 2 * sizeof (uint64_t); break; case DTRACEACT_STOP: case DTRACEACT_BREAKPOINT: case DTRACEACT_PANIC: break; case DTRACEACT_CHILL: case DTRACEACT_DISCARD: case DTRACEACT_RAISE: case DTRACEACT_PIDRESUME: /* __APPLE__ */ if (dp == NULL) return (EINVAL); break; case DTRACEACT_EXIT: if (dp == NULL || (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) || (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) return (EINVAL); break; case DTRACEACT_SPECULATE: if (ecb->dte_size > sizeof (dtrace_epid_t)) return (EINVAL); if (dp == NULL) return (EINVAL); state->dts_speculates = 1; break; case DTRACEACT_COMMIT: { dtrace_action_t *act = ecb->dte_action; for (; act != NULL; act = act->dta_next) { if (act->dta_kind == DTRACEACT_COMMIT) return (EINVAL); } if (dp == NULL) return (EINVAL); break; } default: return (EINVAL); } if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) { /* * If this is a data-storing action or a speculate, * we must be sure that there isn't a commit on the * action chain. */ dtrace_action_t *act = ecb->dte_action; for (; act != NULL; act = act->dta_next) { if (act->dta_kind == DTRACEACT_COMMIT) return (EINVAL); } } action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP); action->dta_rec.dtrd_size = size; } action->dta_refcnt = 1; rec = &action->dta_rec; size = rec->dtrd_size; for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) { if (!(size & mask)) { align = mask + 1; break; } } action->dta_kind = desc->dtad_kind; if ((action->dta_difo = dp) != NULL) dtrace_difo_hold(dp); rec->dtrd_action = action->dta_kind; rec->dtrd_arg = arg; rec->dtrd_uarg = desc->dtad_uarg; rec->dtrd_alignment = (uint16_t)align; rec->dtrd_format = format; if ((last = ecb->dte_action_last) != NULL) { ASSERT(ecb->dte_action != NULL); action->dta_prev = last; last->dta_next = action; } else { ASSERT(ecb->dte_action == NULL); ecb->dte_action = action; } ecb->dte_action_last = action; return (0); } static void dtrace_ecb_action_remove(dtrace_ecb_t *ecb) { dtrace_action_t *act = ecb->dte_action, *next; dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate; dtrace_difo_t *dp; uint16_t format; if (act != NULL && act->dta_refcnt > 1) { ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1); act->dta_refcnt--; } else { for (; act != NULL; act = next) { next = act->dta_next; ASSERT(next != NULL || act == ecb->dte_action_last); ASSERT(act->dta_refcnt == 1); if ((format = act->dta_rec.dtrd_format) != 0) dtrace_format_remove(ecb->dte_state, format); if ((dp = act->dta_difo) != NULL) dtrace_difo_release(dp, vstate); if (DTRACEACT_ISAGG(act->dta_kind)) { dtrace_ecb_aggregation_destroy(ecb, act); } else { kmem_free(act, sizeof (dtrace_action_t)); } } } ecb->dte_action = NULL; ecb->dte_action_last = NULL; ecb->dte_size = sizeof (dtrace_epid_t); } static void dtrace_ecb_disable(dtrace_ecb_t *ecb) { /* * We disable the ECB by removing it from its probe. */ dtrace_ecb_t *pecb, *prev = NULL; dtrace_probe_t *probe = ecb->dte_probe; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (probe == NULL) { /* * This is the NULL probe; there is nothing to disable. */ return; } for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) { if (pecb == ecb) break; prev = pecb; } ASSERT(pecb != NULL); if (prev == NULL) { probe->dtpr_ecb = ecb->dte_next; } else { prev->dte_next = ecb->dte_next; } if (ecb == probe->dtpr_ecb_last) { ASSERT(ecb->dte_next == NULL); probe->dtpr_ecb_last = prev; } probe->dtpr_provider->dtpv_ecb_count--; /* * The ECB has been disconnected from the probe; now sync to assure * that all CPUs have seen the change before returning. */ dtrace_sync(); if (probe->dtpr_ecb == NULL) { /* * That was the last ECB on the probe; clear the predicate * cache ID for the probe, disable it and sync one more time * to assure that we'll never hit it again. */ dtrace_provider_t *prov = probe->dtpr_provider; ASSERT(ecb->dte_next == NULL); ASSERT(probe->dtpr_ecb_last == NULL); probe->dtpr_predcache = DTRACE_CACHEIDNONE; prov->dtpv_pops.dtps_disable(prov->dtpv_arg, probe->dtpr_id, probe->dtpr_arg); dtrace_sync(); } else { /* * There is at least one ECB remaining on the probe. If there * is _exactly_ one, set the probe's predicate cache ID to be * the predicate cache ID of the remaining ECB. */ ASSERT(probe->dtpr_ecb_last != NULL); ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE); if (probe->dtpr_ecb == probe->dtpr_ecb_last) { dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate; ASSERT(probe->dtpr_ecb->dte_next == NULL); if (p != NULL) probe->dtpr_predcache = p->dtp_cacheid; } ecb->dte_next = NULL; } } static void dtrace_ecb_destroy(dtrace_ecb_t *ecb) { dtrace_state_t *state = ecb->dte_state; dtrace_vstate_t *vstate = &state->dts_vstate; dtrace_predicate_t *pred; dtrace_epid_t epid = ecb->dte_epid; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(ecb->dte_next == NULL); ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb); if ((pred = ecb->dte_predicate) != NULL) dtrace_predicate_release(pred, vstate); dtrace_ecb_action_remove(ecb); ASSERT(state->dts_ecbs[epid - 1] == ecb); state->dts_ecbs[epid - 1] = NULL; kmem_free(ecb, sizeof (dtrace_ecb_t)); } static dtrace_ecb_t * dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe, dtrace_enabling_t *enab) { dtrace_ecb_t *ecb; dtrace_predicate_t *pred; dtrace_actdesc_t *act; dtrace_provider_t *prov; dtrace_ecbdesc_t *desc = enab->dten_current; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(state != NULL); ecb = dtrace_ecb_add(state, probe); ecb->dte_uarg = desc->dted_uarg; if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) { dtrace_predicate_hold(pred); ecb->dte_predicate = pred; } if (probe != NULL) { /* * If the provider shows more leg than the consumer is old * enough to see, we need to enable the appropriate implicit * predicate bits to prevent the ecb from activating at * revealing times. * * Providers specifying DTRACE_PRIV_USER at register time * are stating that they need the /proc-style privilege * model to be enforced, and this is what DTRACE_COND_OWNER * and DTRACE_COND_ZONEOWNER will then do at probe time. */ prov = probe->dtpr_provider; if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) && (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER)) ecb->dte_cond |= DTRACE_COND_OWNER; if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) && (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER)) ecb->dte_cond |= DTRACE_COND_ZONEOWNER; /* * If the provider shows us kernel innards and the user * is lacking sufficient privilege, enable the * DTRACE_COND_USERMODE implicit predicate. */ if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) && (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL)) ecb->dte_cond |= DTRACE_COND_USERMODE; } if (dtrace_ecb_create_cache != NULL) { /* * If we have a cached ecb, we'll use its action list instead * of creating our own (saving both time and space). */ dtrace_ecb_t *cached = dtrace_ecb_create_cache; dtrace_action_t *act_if = cached->dte_action; if (act_if != NULL) { ASSERT(act_if->dta_refcnt > 0); act_if->dta_refcnt++; ecb->dte_action = act_if; ecb->dte_action_last = cached->dte_action_last; ecb->dte_needed = cached->dte_needed; ecb->dte_size = cached->dte_size; ecb->dte_alignment = cached->dte_alignment; } return (ecb); } for (act = desc->dted_action; act != NULL; act = act->dtad_next) { if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) { dtrace_ecb_destroy(ecb); return (NULL); } } dtrace_ecb_resize(ecb); return (dtrace_ecb_create_cache = ecb); } static int dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg) { dtrace_ecb_t *ecb; dtrace_enabling_t *enab = arg; dtrace_state_t *state = enab->dten_vstate->dtvs_state; ASSERT(state != NULL); if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) { /* * This probe was created in a generation for which this * enabling has previously created ECBs; we don't want to * enable it again, so just kick out. */ return (DTRACE_MATCH_NEXT); } if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL) return (DTRACE_MATCH_DONE); if (dtrace_ecb_enable(ecb) < 0) return (DTRACE_MATCH_FAIL); return (DTRACE_MATCH_NEXT); } static dtrace_ecb_t * dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id) { dtrace_ecb_t *ecb; #pragma unused(ecb) /* __APPLE__ */ lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (id == 0 || id > (dtrace_epid_t)state->dts_necbs) return (NULL); ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL); ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id); return (state->dts_ecbs[id - 1]); } static dtrace_aggregation_t * dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id) { dtrace_aggregation_t *agg; #pragma unused(agg) /* __APPLE__ */ lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (id == 0 || id > (dtrace_aggid_t)state->dts_naggregations) return (NULL); ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL); ASSERT((agg = state->dts_aggregations[id - 1]) == NULL || agg->dtag_id == id); return (state->dts_aggregations[id - 1]); } /* * DTrace Buffer Functions * * The following functions manipulate DTrace buffers. Most of these functions * are called in the context of establishing or processing consumer state; * exceptions are explicitly noted. */ /* * Note: called from cross call context. This function switches the two * buffers on a given CPU. The atomicity of this operation is assured by * disabling interrupts while the actual switch takes place; the disabling of * interrupts serializes the execution with any execution of dtrace_probe() on * the same CPU. */ static void dtrace_buffer_switch(dtrace_buffer_t *buf) { caddr_t tomax = buf->dtb_tomax; caddr_t xamot = buf->dtb_xamot; dtrace_icookie_t cookie; ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); ASSERT(!(buf->dtb_flags & DTRACEBUF_RING)); cookie = dtrace_interrupt_disable(); buf->dtb_tomax = xamot; buf->dtb_xamot = tomax; buf->dtb_xamot_drops = buf->dtb_drops; buf->dtb_xamot_offset = buf->dtb_offset; buf->dtb_xamot_errors = buf->dtb_errors; buf->dtb_xamot_flags = buf->dtb_flags; buf->dtb_offset = 0; buf->dtb_drops = 0; buf->dtb_errors = 0; buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED); dtrace_interrupt_enable(cookie); } /* * Note: called from cross call context. This function activates a buffer * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation * is guaranteed by the disabling of interrupts. */ static void dtrace_buffer_activate(dtrace_state_t *state) { dtrace_buffer_t *buf; dtrace_icookie_t cookie = dtrace_interrupt_disable(); buf = &state->dts_buffer[CPU->cpu_id]; if (buf->dtb_tomax != NULL) { /* * We might like to assert that the buffer is marked inactive, * but this isn't necessarily true: the buffer for the CPU * that processes the BEGIN probe has its buffer activated * manually. In this case, we take the (harmless) action * re-clearing the bit INACTIVE bit. */ buf->dtb_flags &= ~DTRACEBUF_INACTIVE; } dtrace_interrupt_enable(cookie); } static int dtrace_buffer_canalloc(size_t size) { if (size > (UINT64_MAX - dtrace_buffer_memory_inuse)) return (B_FALSE); if ((size + dtrace_buffer_memory_inuse) > dtrace_buffer_memory_maxsize) return (B_FALSE); return (B_TRUE); } static int dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags, processorid_t cpu) { dtrace_cpu_t *cp; dtrace_buffer_t *buf; size_t size_before_alloc = dtrace_buffer_memory_inuse; lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (size > (size_t)dtrace_nonroot_maxsize && !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE)) return (EFBIG); cp = cpu_list; do { if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id) continue; buf = &bufs[cp->cpu_id]; /* * If there is already a buffer allocated for this CPU, it * is only possible that this is a DR event. In this case, * the buffer size must match our specified size. */ if (buf->dtb_tomax != NULL) { ASSERT(buf->dtb_size == size); continue; } ASSERT(buf->dtb_xamot == NULL); /* DTrace, please do not eat all the memory. */ if (dtrace_buffer_canalloc(size) == B_FALSE) goto err; if ((buf->dtb_tomax = kmem_zalloc(size, KM_NOSLEEP)) == NULL) goto err; dtrace_buffer_memory_inuse += size; buf->dtb_size = size; buf->dtb_flags = flags; buf->dtb_offset = 0; buf->dtb_drops = 0; if (flags & DTRACEBUF_NOSWITCH) continue; /* DTrace, please do not eat all the memory. */ if (dtrace_buffer_canalloc(size) == B_FALSE) goto err; if ((buf->dtb_xamot = kmem_zalloc(size, KM_NOSLEEP)) == NULL) goto err; dtrace_buffer_memory_inuse += size; } while ((cp = cp->cpu_next) != cpu_list); ASSERT(dtrace_buffer_memory_inuse <= dtrace_buffer_memory_maxsize); return (0); err: cp = cpu_list; do { if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id) continue; buf = &bufs[cp->cpu_id]; if (buf->dtb_xamot != NULL) { ASSERT(buf->dtb_tomax != NULL); ASSERT(buf->dtb_size == size); kmem_free(buf->dtb_xamot, size); } if (buf->dtb_tomax != NULL) { ASSERT(buf->dtb_size == size); kmem_free(buf->dtb_tomax, size); } buf->dtb_tomax = NULL; buf->dtb_xamot = NULL; buf->dtb_size = 0; } while ((cp = cp->cpu_next) != cpu_list); /* Restore the size saved before allocating memory */ dtrace_buffer_memory_inuse = size_before_alloc; return (ENOMEM); } /* * Note: called from probe context. This function just increments the drop * count on a buffer. It has been made a function to allow for the * possibility of understanding the source of mysterious drop counts. (A * problem for which one may be particularly disappointed that DTrace cannot * be used to understand DTrace.) */ static void dtrace_buffer_drop(dtrace_buffer_t *buf) { buf->dtb_drops++; } /* * Note: called from probe context. This function is called to reserve space * in a buffer. If mstate is non-NULL, sets the scratch base and size in the * mstate. Returns the new offset in the buffer, or a negative value if an * error has occurred. */ static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align, dtrace_state_t *state, dtrace_mstate_t *mstate) { intptr_t offs = buf->dtb_offset, soffs; intptr_t woffs; caddr_t tomax; size_t total_off; if (buf->dtb_flags & DTRACEBUF_INACTIVE) return (-1); if ((tomax = buf->dtb_tomax) == NULL) { dtrace_buffer_drop(buf); return (-1); } if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) { while (offs & (align - 1)) { /* * Assert that our alignment is off by a number which * is itself sizeof (uint32_t) aligned. */ ASSERT(!((align - (offs & (align - 1))) & (sizeof (uint32_t) - 1))); DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE); offs += sizeof (uint32_t); } if ((uint64_t)(soffs = offs + needed) > buf->dtb_size) { dtrace_buffer_drop(buf); return (-1); } if (mstate == NULL) return (offs); mstate->dtms_scratch_base = (uintptr_t)tomax + soffs; mstate->dtms_scratch_size = buf->dtb_size - soffs; mstate->dtms_scratch_ptr = mstate->dtms_scratch_base; return (offs); } if (buf->dtb_flags & DTRACEBUF_FILL) { if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN && (buf->dtb_flags & DTRACEBUF_FULL)) return (-1); goto out; } total_off = needed + (offs & (align - 1)); /* * For a ring buffer, life is quite a bit more complicated. Before * we can store any padding, we need to adjust our wrapping offset. * (If we've never before wrapped or we're not about to, no adjustment * is required.) */ if ((buf->dtb_flags & DTRACEBUF_WRAPPED) || offs + total_off > buf->dtb_size) { woffs = buf->dtb_xamot_offset; if (offs + total_off > buf->dtb_size) { /* * We can't fit in the end of the buffer. First, a * sanity check that we can fit in the buffer at all. */ if (total_off > buf->dtb_size) { dtrace_buffer_drop(buf); return (-1); } /* * We're going to be storing at the top of the buffer, * so now we need to deal with the wrapped offset. We * only reset our wrapped offset to 0 if it is * currently greater than the current offset. If it * is less than the current offset, it is because a * previous allocation induced a wrap -- but the * allocation didn't subsequently take the space due * to an error or false predicate evaluation. In this * case, we'll just leave the wrapped offset alone: if * the wrapped offset hasn't been advanced far enough * for this allocation, it will be adjusted in the * lower loop. */ if (buf->dtb_flags & DTRACEBUF_WRAPPED) { if (woffs >= offs) woffs = 0; } else { woffs = 0; } /* * Now we know that we're going to be storing to the * top of the buffer and that there is room for us * there. We need to clear the buffer from the current * offset to the end (there may be old gunk there). */ while ((uint64_t)offs < buf->dtb_size) tomax[offs++] = 0; /* * We need to set our offset to zero. And because we * are wrapping, we need to set the bit indicating as * much. We can also adjust our needed space back * down to the space required by the ECB -- we know * that the top of the buffer is aligned. */ offs = 0; total_off = needed; buf->dtb_flags |= DTRACEBUF_WRAPPED; } else { /* * There is room for us in the buffer, so we simply * need to check the wrapped offset. */ if (woffs < offs) { /* * The wrapped offset is less than the offset. * This can happen if we allocated buffer space * that induced a wrap, but then we didn't * subsequently take the space due to an error * or false predicate evaluation. This is * okay; we know that _this_ allocation isn't * going to induce a wrap. We still can't * reset the wrapped offset to be zero, * however: the space may have been trashed in * the previous failed probe attempt. But at * least the wrapped offset doesn't need to * be adjusted at all... */ goto out; } } while (offs + total_off > (size_t)woffs) { dtrace_epid_t epid = *(uint32_t *)(tomax + woffs); size_t size; if (epid == DTRACE_EPIDNONE) { size = sizeof (uint32_t); } else { ASSERT(epid <= (dtrace_epid_t)state->dts_necbs); ASSERT(state->dts_ecbs[epid - 1] != NULL); size = state->dts_ecbs[epid - 1]->dte_size; } ASSERT(woffs + size <= buf->dtb_size); ASSERT(size != 0); if (woffs + size == buf->dtb_size) { /* * We've reached the end of the buffer; we want * to set the wrapped offset to 0 and break * out. However, if the offs is 0, then we're * in a strange edge-condition: the amount of * space that we want to reserve plus the size * of the record that we're overwriting is * greater than the size of the buffer. This * is problematic because if we reserve the * space but subsequently don't consume it (due * to a failed predicate or error) the wrapped * offset will be 0 -- yet the EPID at offset 0 * will not be committed. This situation is * relatively easy to deal with: if we're in * this case, the buffer is indistinguishable * from one that hasn't wrapped; we need only * finish the job by clearing the wrapped bit, * explicitly setting the offset to be 0, and * zero'ing out the old data in the buffer. */ if (offs == 0) { buf->dtb_flags &= ~DTRACEBUF_WRAPPED; buf->dtb_offset = 0; woffs = total_off; while ((uint64_t)woffs < buf->dtb_size) tomax[woffs++] = 0; } woffs = 0; break; } woffs += size; } /* * We have a wrapped offset. It may be that the wrapped offset * has become zero -- that's okay. */ buf->dtb_xamot_offset = woffs; } out: /* * Now we can plow the buffer with any necessary padding. */ while (offs & (align - 1)) { /* * Assert that our alignment is off by a number which * is itself sizeof (uint32_t) aligned. */ ASSERT(!((align - (offs & (align - 1))) & (sizeof (uint32_t) - 1))); DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE); offs += sizeof (uint32_t); } if (buf->dtb_flags & DTRACEBUF_FILL) { if (offs + needed > buf->dtb_size - state->dts_reserve) { buf->dtb_flags |= DTRACEBUF_FULL; return (-1); } } if (mstate == NULL) return (offs); /* * For ring buffers and fill buffers, the scratch space is always * the inactive buffer. */ mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot; mstate->dtms_scratch_size = buf->dtb_size; mstate->dtms_scratch_ptr = mstate->dtms_scratch_base; return (offs); } static void dtrace_buffer_polish(dtrace_buffer_t *buf) { ASSERT(buf->dtb_flags & DTRACEBUF_RING); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (!(buf->dtb_flags & DTRACEBUF_WRAPPED)) return; /* * We need to polish the ring buffer. There are three cases: * * - The first (and presumably most common) is that there is no gap * between the buffer offset and the wrapped offset. In this case, * there is nothing in the buffer that isn't valid data; we can * mark the buffer as polished and return. * * - The second (less common than the first but still more common * than the third) is that there is a gap between the buffer offset * and the wrapped offset, and the wrapped offset is larger than the * buffer offset. This can happen because of an alignment issue, or * can happen because of a call to dtrace_buffer_reserve() that * didn't subsequently consume the buffer space. In this case, * we need to zero the data from the buffer offset to the wrapped * offset. * * - The third (and least common) is that there is a gap between the * buffer offset and the wrapped offset, but the wrapped offset is * _less_ than the buffer offset. This can only happen because a * call to dtrace_buffer_reserve() induced a wrap, but the space * was not subsequently consumed. In this case, we need to zero the * space from the offset to the end of the buffer _and_ from the * top of the buffer to the wrapped offset. */ if (buf->dtb_offset < buf->dtb_xamot_offset) { bzero(buf->dtb_tomax + buf->dtb_offset, buf->dtb_xamot_offset - buf->dtb_offset); } if (buf->dtb_offset > buf->dtb_xamot_offset) { bzero(buf->dtb_tomax + buf->dtb_offset, buf->dtb_size - buf->dtb_offset); bzero(buf->dtb_tomax, buf->dtb_xamot_offset); } } static void dtrace_buffer_free(dtrace_buffer_t *bufs) { int i; for (i = 0; i < (int)NCPU; i++) { dtrace_buffer_t *buf = &bufs[i]; if (buf->dtb_tomax == NULL) { ASSERT(buf->dtb_xamot == NULL); ASSERT(buf->dtb_size == 0); continue; } if (buf->dtb_xamot != NULL) { ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); kmem_free(buf->dtb_xamot, buf->dtb_size); ASSERT(dtrace_buffer_memory_inuse >= buf->dtb_size); dtrace_buffer_memory_inuse -= buf->dtb_size; } kmem_free(buf->dtb_tomax, buf->dtb_size); ASSERT(dtrace_buffer_memory_inuse >= buf->dtb_size); dtrace_buffer_memory_inuse -= buf->dtb_size; buf->dtb_size = 0; buf->dtb_tomax = NULL; buf->dtb_xamot = NULL; } } /* * DTrace Enabling Functions */ static dtrace_enabling_t * dtrace_enabling_create(dtrace_vstate_t *vstate) { dtrace_enabling_t *enab; enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP); enab->dten_vstate = vstate; return (enab); } static void dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb) { dtrace_ecbdesc_t **ndesc; size_t osize, nsize; /* * We can't add to enablings after we've enabled them, or after we've * retained them. */ ASSERT(enab->dten_probegen == 0); ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL); /* APPLE NOTE: this protects against gcc 4.0 botch on x86 */ if (ecb == NULL) return; if (enab->dten_ndesc < enab->dten_maxdesc) { enab->dten_desc[enab->dten_ndesc++] = ecb; return; } osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *); if (enab->dten_maxdesc == 0) { enab->dten_maxdesc = 1; } else { enab->dten_maxdesc <<= 1; } ASSERT(enab->dten_ndesc < enab->dten_maxdesc); nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *); ndesc = kmem_zalloc(nsize, KM_SLEEP); bcopy(enab->dten_desc, ndesc, osize); kmem_free(enab->dten_desc, osize); enab->dten_desc = ndesc; enab->dten_desc[enab->dten_ndesc++] = ecb; } static void dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb, dtrace_probedesc_t *pd) { dtrace_ecbdesc_t *new; dtrace_predicate_t *pred; dtrace_actdesc_t *act; /* * We're going to create a new ECB description that matches the * specified ECB in every way, but has the specified probe description. */ new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP); if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL) dtrace_predicate_hold(pred); for (act = ecb->dted_action; act != NULL; act = act->dtad_next) dtrace_actdesc_hold(act); new->dted_action = ecb->dted_action; new->dted_pred = ecb->dted_pred; new->dted_probe = *pd; new->dted_uarg = ecb->dted_uarg; dtrace_enabling_add(enab, new); } static void dtrace_enabling_dump(dtrace_enabling_t *enab) { int i; for (i = 0; i < enab->dten_ndesc; i++) { dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe; cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i, desc->dtpd_provider, desc->dtpd_mod, desc->dtpd_func, desc->dtpd_name); } } static void dtrace_enabling_destroy(dtrace_enabling_t *enab) { int i; dtrace_ecbdesc_t *ep; dtrace_vstate_t *vstate = enab->dten_vstate; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); for (i = 0; i < enab->dten_ndesc; i++) { dtrace_actdesc_t *act, *next; dtrace_predicate_t *pred; ep = enab->dten_desc[i]; if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) dtrace_predicate_release(pred, vstate); for (act = ep->dted_action; act != NULL; act = next) { next = act->dtad_next; dtrace_actdesc_release(act, vstate); } kmem_free(ep, sizeof (dtrace_ecbdesc_t)); } kmem_free(enab->dten_desc, enab->dten_maxdesc * sizeof (dtrace_enabling_t *)); /* * If this was a retained enabling, decrement the dts_nretained count * and take it off of the dtrace_retained list. */ if (enab->dten_prev != NULL || enab->dten_next != NULL || dtrace_retained == enab) { ASSERT(enab->dten_vstate->dtvs_state != NULL); ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0); enab->dten_vstate->dtvs_state->dts_nretained--; dtrace_retained_gen++; } if (enab->dten_prev == NULL) { if (dtrace_retained == enab) { dtrace_retained = enab->dten_next; if (dtrace_retained != NULL) dtrace_retained->dten_prev = NULL; } } else { ASSERT(enab != dtrace_retained); ASSERT(dtrace_retained != NULL); enab->dten_prev->dten_next = enab->dten_next; } if (enab->dten_next != NULL) { ASSERT(dtrace_retained != NULL); enab->dten_next->dten_prev = enab->dten_prev; } kmem_free(enab, sizeof (dtrace_enabling_t)); } static int dtrace_enabling_retain(dtrace_enabling_t *enab) { dtrace_state_t *state; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL); ASSERT(enab->dten_vstate != NULL); state = enab->dten_vstate->dtvs_state; ASSERT(state != NULL); /* * We only allow each state to retain dtrace_retain_max enablings. */ if (state->dts_nretained >= dtrace_retain_max) return (ENOSPC); state->dts_nretained++; dtrace_retained_gen++; if (dtrace_retained == NULL) { dtrace_retained = enab; return (0); } enab->dten_next = dtrace_retained; dtrace_retained->dten_prev = enab; dtrace_retained = enab; return (0); } static int dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match, dtrace_probedesc_t *create) { dtrace_enabling_t *new, *enab; int found = 0, err = ENOENT; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN); ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN); ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN); ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN); new = dtrace_enabling_create(&state->dts_vstate); /* * Iterate over all retained enablings, looking for enablings that * match the specified state. */ for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { int i; /* * dtvs_state can only be NULL for helper enablings -- and * helper enablings can't be retained. */ ASSERT(enab->dten_vstate->dtvs_state != NULL); if (enab->dten_vstate->dtvs_state != state) continue; /* * Now iterate over each probe description; we're looking for * an exact match to the specified probe description. */ for (i = 0; i < enab->dten_ndesc; i++) { dtrace_ecbdesc_t *ep = enab->dten_desc[i]; dtrace_probedesc_t *pd = &ep->dted_probe; /* APPLE NOTE: Darwin employs size bounded string operation. */ if (strncmp(pd->dtpd_provider, match->dtpd_provider, DTRACE_PROVNAMELEN)) continue; if (strncmp(pd->dtpd_mod, match->dtpd_mod, DTRACE_MODNAMELEN)) continue; if (strncmp(pd->dtpd_func, match->dtpd_func, DTRACE_FUNCNAMELEN)) continue; if (strncmp(pd->dtpd_name, match->dtpd_name, DTRACE_NAMELEN)) continue; /* * We have a winning probe! Add it to our growing * enabling. */ found = 1; dtrace_enabling_addlike(new, ep, create); } } if (!found || (err = dtrace_enabling_retain(new)) != 0) { dtrace_enabling_destroy(new); return (err); } return (0); } static void dtrace_enabling_retract(dtrace_state_t *state) { dtrace_enabling_t *enab, *next; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); /* * Iterate over all retained enablings, destroy the enablings retained * for the specified state. */ for (enab = dtrace_retained; enab != NULL; enab = next) { next = enab->dten_next; /* * dtvs_state can only be NULL for helper enablings -- and * helper enablings can't be retained. */ ASSERT(enab->dten_vstate->dtvs_state != NULL); if (enab->dten_vstate->dtvs_state == state) { ASSERT(state->dts_nretained > 0); dtrace_enabling_destroy(enab); } } ASSERT(state->dts_nretained == 0); } static int dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched) { int i = 0; int total_matched = 0, matched = 0; lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); for (i = 0; i < enab->dten_ndesc; i++) { dtrace_ecbdesc_t *ep = enab->dten_desc[i]; enab->dten_current = ep; enab->dten_error = 0; /* * If a provider failed to enable a probe then get out and * let the consumer know we failed. */ if ((matched = dtrace_probe_enable(&ep->dted_probe, enab)) < 0) return (EBUSY); total_matched += matched; if (enab->dten_error != 0) { /* * If we get an error half-way through enabling the * probes, we kick out -- perhaps with some number of * them enabled. Leaving enabled probes enabled may * be slightly confusing for user-level, but we expect * that no one will attempt to actually drive on in * the face of such errors. If this is an anonymous * enabling (indicated with a NULL nmatched pointer), * we cmn_err() a message. We aren't expecting to * get such an error -- such as it can exist at all, * it would be a result of corrupted DOF in the driver * properties. */ if (nmatched == NULL) { cmn_err(CE_WARN, "dtrace_enabling_match() " "error on %p: %d", (void *)ep, enab->dten_error); } return (enab->dten_error); } } enab->dten_probegen = dtrace_probegen; if (nmatched != NULL) *nmatched = total_matched; return (0); } static void dtrace_enabling_matchall(void) { dtrace_enabling_t *enab; lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_lock); /* * Iterate over all retained enablings to see if any probes match * against them. We only perform this operation on enablings for which * we have sufficient permissions by virtue of being in the global zone * or in the same zone as the DTrace client. Because we can be called * after dtrace_detach() has been called, we cannot assert that there * are retained enablings. We can safely load from dtrace_retained, * however: the taskq_destroy() at the end of dtrace_detach() will * block pending our completion. */ /* * Darwin doesn't do zones. * Behave as if always in "global" zone." */ for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { (void) dtrace_enabling_match(enab, NULL); } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); } /* * If an enabling is to be enabled without having matched probes (that is, if * dtrace_state_go() is to be called on the underlying dtrace_state_t), the * enabling must be _primed_ by creating an ECB for every ECB description. * This must be done to assure that we know the number of speculations, the * number of aggregations, the minimum buffer size needed, etc. before we * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually * enabling any probes, we create ECBs for every ECB decription, but with a * NULL probe -- which is exactly what this function does. */ static void dtrace_enabling_prime(dtrace_state_t *state) { dtrace_enabling_t *enab; int i; for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { ASSERT(enab->dten_vstate->dtvs_state != NULL); if (enab->dten_vstate->dtvs_state != state) continue; /* * We don't want to prime an enabling more than once, lest * we allow a malicious user to induce resource exhaustion. * (The ECBs that result from priming an enabling aren't * leaked -- but they also aren't deallocated until the * consumer state is destroyed.) */ if (enab->dten_primed) continue; for (i = 0; i < enab->dten_ndesc; i++) { enab->dten_current = enab->dten_desc[i]; (void) dtrace_probe_enable(NULL, enab); } enab->dten_primed = 1; } } /* * Called to indicate that probes should be provided due to retained * enablings. This is implemented in terms of dtrace_probe_provide(), but it * must take an initial lap through the enabling calling the dtps_provide() * entry point explicitly to allow for autocreated probes. */ static void dtrace_enabling_provide(dtrace_provider_t *prv) { int i, all = 0; dtrace_probedesc_t desc; dtrace_genid_t gen; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&dtrace_provider_lock, LCK_MTX_ASSERT_OWNED); if (prv == NULL) { all = 1; prv = dtrace_provider; } do { dtrace_enabling_t *enab; void *parg = prv->dtpv_arg; retry: gen = dtrace_retained_gen; for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) { for (i = 0; i < enab->dten_ndesc; i++) { desc = enab->dten_desc[i]->dted_probe; lck_mtx_unlock(&dtrace_lock); prv->dtpv_pops.dtps_provide(parg, &desc); lck_mtx_lock(&dtrace_lock); /* * Process the retained enablings again if * they have changed while we weren't holding * dtrace_lock. */ if (gen != dtrace_retained_gen) goto retry; } } } while (all && (prv = prv->dtpv_next) != NULL); lck_mtx_unlock(&dtrace_lock); dtrace_probe_provide(NULL, all ? NULL : prv); lck_mtx_lock(&dtrace_lock); } /* * DTrace DOF Functions */ /*ARGSUSED*/ static void dtrace_dof_error(dof_hdr_t *dof, const char *str) { #pragma unused(dof) /* __APPLE__ */ if (dtrace_err_verbose) cmn_err(CE_WARN, "failed to process DOF: %s", str); #ifdef DTRACE_ERRDEBUG dtrace_errdebug(str); #endif } /* * Create DOF out of a currently enabled state. Right now, we only create * DOF containing the run-time options -- but this could be expanded to create * complete DOF representing the enabled state. */ static dof_hdr_t * dtrace_dof_create(dtrace_state_t *state) { dof_hdr_t *dof; dof_sec_t *sec; dof_optdesc_t *opt; int i, len = sizeof (dof_hdr_t) + roundup(sizeof (dof_sec_t), sizeof (uint64_t)) + sizeof (dof_optdesc_t) * DTRACEOPT_MAX; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); dof = dt_kmem_zalloc_aligned(len, 8, KM_SLEEP); dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0; dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1; dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2; dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3; dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE; dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE; dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION; dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION; dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS; dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS; dof->dofh_flags = 0; dof->dofh_hdrsize = sizeof (dof_hdr_t); dof->dofh_secsize = sizeof (dof_sec_t); dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */ dof->dofh_secoff = sizeof (dof_hdr_t); dof->dofh_loadsz = len; dof->dofh_filesz = len; dof->dofh_pad = 0; /* * Fill in the option section header... */ sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t)); sec->dofs_type = DOF_SECT_OPTDESC; sec->dofs_align = sizeof (uint64_t); sec->dofs_flags = DOF_SECF_LOAD; sec->dofs_entsize = sizeof (dof_optdesc_t); opt = (dof_optdesc_t *)((uintptr_t)sec + roundup(sizeof (dof_sec_t), sizeof (uint64_t))); sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof; sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX; for (i = 0; i < DTRACEOPT_MAX; i++) { opt[i].dofo_option = i; opt[i].dofo_strtab = DOF_SECIDX_NONE; opt[i].dofo_value = state->dts_options[i]; } return (dof); } static dof_hdr_t * dtrace_dof_copyin(user_addr_t uarg, int *errp) { dof_hdr_t hdr, *dof; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_NOTOWNED); /* * First, we're going to copyin() the sizeof (dof_hdr_t). */ if (copyin(uarg, &hdr, sizeof (hdr)) != 0) { dtrace_dof_error(NULL, "failed to copyin DOF header"); *errp = EFAULT; return (NULL); } /* * Now we'll allocate the entire DOF and copy it in -- provided * that the length isn't outrageous. */ if (hdr.dofh_loadsz >= (uint64_t)dtrace_dof_maxsize) { dtrace_dof_error(&hdr, "load size exceeds maximum"); *errp = E2BIG; return (NULL); } if (hdr.dofh_loadsz < sizeof (hdr)) { dtrace_dof_error(&hdr, "invalid load size"); *errp = EINVAL; return (NULL); } dof = dt_kmem_alloc_aligned(hdr.dofh_loadsz, 8, KM_SLEEP); if (copyin(uarg, dof, hdr.dofh_loadsz) != 0 || dof->dofh_loadsz != hdr.dofh_loadsz) { dt_kmem_free_aligned(dof, hdr.dofh_loadsz); *errp = EFAULT; return (NULL); } return (dof); } static dof_hdr_t * dtrace_dof_copyin_from_proc(proc_t* p, user_addr_t uarg, int *errp) { dof_hdr_t hdr, *dof; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_NOTOWNED); /* * First, we're going to copyin() the sizeof (dof_hdr_t). */ if (uread(p, &hdr, sizeof(hdr), uarg) != KERN_SUCCESS) { dtrace_dof_error(NULL, "failed to copyin DOF header"); *errp = EFAULT; return (NULL); } /* * Now we'll allocate the entire DOF and copy it in -- provided * that the length isn't outrageous. */ if (hdr.dofh_loadsz >= (uint64_t)dtrace_dof_maxsize) { dtrace_dof_error(&hdr, "load size exceeds maximum"); *errp = E2BIG; return (NULL); } if (hdr.dofh_loadsz < sizeof (hdr)) { dtrace_dof_error(&hdr, "invalid load size"); *errp = EINVAL; return (NULL); } dof = dt_kmem_alloc_aligned(hdr.dofh_loadsz, 8, KM_SLEEP); if (uread(p, dof, hdr.dofh_loadsz, uarg) != KERN_SUCCESS) { dt_kmem_free_aligned(dof, hdr.dofh_loadsz); *errp = EFAULT; return (NULL); } return (dof); } static dof_hdr_t * dtrace_dof_property(const char *name) { uchar_t *buf; uint64_t loadsz; unsigned int len, i; dof_hdr_t *dof; /* * Unfortunately, array of values in .conf files are always (and * only) interpreted to be integer arrays. We must read our DOF * as an integer array, and then squeeze it into a byte array. */ if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0, name, (int **)&buf, &len) != DDI_PROP_SUCCESS) return (NULL); for (i = 0; i < len; i++) buf[i] = (uchar_t)(((int *)buf)[i]); if (len < sizeof (dof_hdr_t)) { ddi_prop_free(buf); dtrace_dof_error(NULL, "truncated header"); return (NULL); } if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) { ddi_prop_free(buf); dtrace_dof_error(NULL, "truncated DOF"); return (NULL); } if (loadsz >= (uint64_t)dtrace_dof_maxsize) { ddi_prop_free(buf); dtrace_dof_error(NULL, "oversized DOF"); return (NULL); } dof = dt_kmem_alloc_aligned(loadsz, 8, KM_SLEEP); bcopy(buf, dof, loadsz); ddi_prop_free(buf); return (dof); } static void dtrace_dof_destroy(dof_hdr_t *dof) { dt_kmem_free_aligned(dof, dof->dofh_loadsz); } /* * Return the dof_sec_t pointer corresponding to a given section index. If the * index is not valid, dtrace_dof_error() is called and NULL is returned. If * a type other than DOF_SECT_NONE is specified, the header is checked against * this type and NULL is returned if the types do not match. */ static dof_sec_t * dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i) { dof_sec_t *sec = (dof_sec_t *)(uintptr_t) ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize); if (i >= dof->dofh_secnum) { dtrace_dof_error(dof, "referenced section index is invalid"); return (NULL); } if (!(sec->dofs_flags & DOF_SECF_LOAD)) { dtrace_dof_error(dof, "referenced section is not loadable"); return (NULL); } if (type != DOF_SECT_NONE && type != sec->dofs_type) { dtrace_dof_error(dof, "referenced section is the wrong type"); return (NULL); } return (sec); } static dtrace_probedesc_t * dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc) { dof_probedesc_t *probe; dof_sec_t *strtab; uintptr_t daddr = (uintptr_t)dof; uintptr_t str; size_t size; if (sec->dofs_type != DOF_SECT_PROBEDESC) { dtrace_dof_error(dof, "invalid probe section"); return (NULL); } if (sec->dofs_align != sizeof (dof_secidx_t)) { dtrace_dof_error(dof, "bad alignment in probe description"); return (NULL); } if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) { dtrace_dof_error(dof, "truncated probe description"); return (NULL); } probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset); strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab); if (strtab == NULL) return (NULL); str = daddr + strtab->dofs_offset; size = strtab->dofs_size; if (probe->dofp_provider >= strtab->dofs_size) { dtrace_dof_error(dof, "corrupt probe provider"); return (NULL); } (void) strncpy(desc->dtpd_provider, (char *)(str + probe->dofp_provider), MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider)); /* APPLE NOTE: Darwin employs size bounded string operation. */ desc->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; if (probe->dofp_mod >= strtab->dofs_size) { dtrace_dof_error(dof, "corrupt probe module"); return (NULL); } (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod), MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod)); /* APPLE NOTE: Darwin employs size bounded string operation. */ desc->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; if (probe->dofp_func >= strtab->dofs_size) { dtrace_dof_error(dof, "corrupt probe function"); return (NULL); } (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func), MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func)); /* APPLE NOTE: Darwin employs size bounded string operation. */ desc->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; if (probe->dofp_name >= strtab->dofs_size) { dtrace_dof_error(dof, "corrupt probe name"); return (NULL); } (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name), MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name)); /* APPLE NOTE: Darwin employs size bounded string operation. */ desc->dtpd_name[DTRACE_NAMELEN - 1] = '\0'; return (desc); } static dtrace_difo_t * dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, cred_t *cr) { dtrace_difo_t *dp; size_t ttl = 0; dof_difohdr_t *dofd; uintptr_t daddr = (uintptr_t)dof; size_t max_size = dtrace_difo_maxsize; uint_t i; int l, n; static const struct { int section; int bufoffs; int lenoffs; int entsize; int align; const char *msg; } difo[] = { { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf), offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t), sizeof (dif_instr_t), "multiple DIF sections" }, { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab), offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t), sizeof (uint64_t), "multiple integer tables" }, { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab), offsetof(dtrace_difo_t, dtdo_strlen), 0, sizeof (char), "multiple string tables" }, { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab), offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t), sizeof (uint_t), "multiple variable tables" }, { DOF_SECT_NONE, 0, 0, 0, 0, NULL } }; if (sec->dofs_type != DOF_SECT_DIFOHDR) { dtrace_dof_error(dof, "invalid DIFO header section"); return (NULL); } if (sec->dofs_align != sizeof (dof_secidx_t)) { dtrace_dof_error(dof, "bad alignment in DIFO header"); return (NULL); } if (sec->dofs_size < sizeof (dof_difohdr_t) || sec->dofs_size % sizeof (dof_secidx_t)) { dtrace_dof_error(dof, "bad size in DIFO header"); return (NULL); } dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset); n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1; dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP); dp->dtdo_rtype = dofd->dofd_rtype; for (l = 0; l < n; l++) { dof_sec_t *subsec; void **bufp; uint32_t *lenp; if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE, dofd->dofd_links[l])) == NULL) goto err; /* invalid section link */ if (ttl + subsec->dofs_size > max_size) { dtrace_dof_error(dof, "exceeds maximum size"); goto err; } ttl += subsec->dofs_size; for (i = 0; difo[i].section != DOF_SECT_NONE; i++) { if (subsec->dofs_type != (uint32_t)difo[i].section) continue; if (!(subsec->dofs_flags & DOF_SECF_LOAD)) { dtrace_dof_error(dof, "section not loaded"); goto err; } if (subsec->dofs_align != (uint32_t)difo[i].align) { dtrace_dof_error(dof, "bad alignment"); goto err; } bufp = (void **)((uintptr_t)dp + difo[i].bufoffs); lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs); if (*bufp != NULL) { dtrace_dof_error(dof, difo[i].msg); goto err; } if ((uint32_t)difo[i].entsize != subsec->dofs_entsize) { dtrace_dof_error(dof, "entry size mismatch"); goto err; } if (subsec->dofs_entsize != 0 && (subsec->dofs_size % subsec->dofs_entsize) != 0) { dtrace_dof_error(dof, "corrupt entry size"); goto err; } *lenp = subsec->dofs_size; *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP); bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset), *bufp, subsec->dofs_size); if (subsec->dofs_entsize != 0) *lenp /= subsec->dofs_entsize; break; } /* * If we encounter a loadable DIFO sub-section that is not * known to us, assume this is a broken program and fail. */ if (difo[i].section == DOF_SECT_NONE && (subsec->dofs_flags & DOF_SECF_LOAD)) { dtrace_dof_error(dof, "unrecognized DIFO subsection"); goto err; } } if (dp->dtdo_buf == NULL) { /* * We can't have a DIF object without DIF text. */ dtrace_dof_error(dof, "missing DIF text"); goto err; } /* * Before we validate the DIF object, run through the variable table * looking for the strings -- if any of their size are under, we'll set * their size to be the system-wide default string size. Note that * this should _not_ happen if the "strsize" option has been set -- * in this case, the compiler should have set the size to reflect the * setting of the option. */ for (i = 0; i < dp->dtdo_varlen; i++) { dtrace_difv_t *v = &dp->dtdo_vartab[i]; dtrace_diftype_t *t = &v->dtdv_type; if (v->dtdv_id < DIF_VAR_OTHER_UBASE) continue; if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0) t->dtdt_size = dtrace_strsize_default; } if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0) goto err; dtrace_difo_init(dp, vstate); return (dp); err: kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t)); kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t)); kmem_free(dp->dtdo_strtab, dp->dtdo_strlen); kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t)); kmem_free(dp, sizeof (dtrace_difo_t)); return (NULL); } static dtrace_predicate_t * dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, cred_t *cr) { dtrace_difo_t *dp; if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL) return (NULL); return (dtrace_predicate_create(dp)); } static dtrace_actdesc_t * dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, cred_t *cr) { dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next; dof_actdesc_t *desc; dof_sec_t *difosec; size_t offs; uintptr_t daddr = (uintptr_t)dof; uint64_t arg; dtrace_actkind_t kind; if (sec->dofs_type != DOF_SECT_ACTDESC) { dtrace_dof_error(dof, "invalid action section"); return (NULL); } if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) { dtrace_dof_error(dof, "truncated action description"); return (NULL); } if (sec->dofs_align != sizeof (uint64_t)) { dtrace_dof_error(dof, "bad alignment in action description"); return (NULL); } if (sec->dofs_size < sec->dofs_entsize) { dtrace_dof_error(dof, "section entry size exceeds total size"); return (NULL); } if (sec->dofs_entsize != sizeof (dof_actdesc_t)) { dtrace_dof_error(dof, "bad entry size in action description"); return (NULL); } if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) { dtrace_dof_error(dof, "actions exceed dtrace_actions_max"); return (NULL); } for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) { desc = (dof_actdesc_t *)(daddr + (uintptr_t)sec->dofs_offset + offs); kind = (dtrace_actkind_t)desc->dofa_kind; if (DTRACEACT_ISPRINTFLIKE(kind) && (kind != DTRACEACT_PRINTA || desc->dofa_strtab != DOF_SECIDX_NONE)) { dof_sec_t *strtab; char *str, *fmt; uint64_t i; /* * printf()-like actions must have a format string. */ if ((strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL) goto err; str = (char *)((uintptr_t)dof + (uintptr_t)strtab->dofs_offset); for (i = desc->dofa_arg; i < strtab->dofs_size; i++) { if (str[i] == '\0') break; } if (i >= strtab->dofs_size) { dtrace_dof_error(dof, "bogus format string"); goto err; } if (i == desc->dofa_arg) { dtrace_dof_error(dof, "empty format string"); goto err; } i -= desc->dofa_arg; fmt = kmem_alloc(i + 1, KM_SLEEP); bcopy(&str[desc->dofa_arg], fmt, i + 1); arg = (uint64_t)(uintptr_t)fmt; } else { if (kind == DTRACEACT_PRINTA) { ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE); arg = 0; } else { arg = desc->dofa_arg; } } act = dtrace_actdesc_create(kind, desc->dofa_ntuple, desc->dofa_uarg, arg); if (last != NULL) { last->dtad_next = act; } else { first = act; } last = act; if (desc->dofa_difo == DOF_SECIDX_NONE) continue; if ((difosec = dtrace_dof_sect(dof, DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL) goto err; act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr); if (act->dtad_difo == NULL) goto err; } ASSERT(first != NULL); return (first); err: for (act = first; act != NULL; act = next) { next = act->dtad_next; dtrace_actdesc_release(act, vstate); } return (NULL); } static dtrace_ecbdesc_t * dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate, cred_t *cr) { dtrace_ecbdesc_t *ep; dof_ecbdesc_t *ecb; dtrace_probedesc_t *desc; dtrace_predicate_t *pred = NULL; if (sec->dofs_size < sizeof (dof_ecbdesc_t)) { dtrace_dof_error(dof, "truncated ECB description"); return (NULL); } if (sec->dofs_align != sizeof (uint64_t)) { dtrace_dof_error(dof, "bad alignment in ECB description"); return (NULL); } ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset); sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes); if (sec == NULL) return (NULL); ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP); ep->dted_uarg = ecb->dofe_uarg; desc = &ep->dted_probe; if (dtrace_dof_probedesc(dof, sec, desc) == NULL) goto err; if (ecb->dofe_pred != DOF_SECIDX_NONE) { if ((sec = dtrace_dof_sect(dof, DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL) goto err; if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL) goto err; ep->dted_pred.dtpdd_predicate = pred; } if (ecb->dofe_actions != DOF_SECIDX_NONE) { if ((sec = dtrace_dof_sect(dof, DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL) goto err; ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr); if (ep->dted_action == NULL) goto err; } return (ep); err: if (pred != NULL) dtrace_predicate_release(pred, vstate); kmem_free(ep, sizeof (dtrace_ecbdesc_t)); return (NULL); } /* * APPLE NOTE: dyld handles dof relocation. * Darwin does not need dtrace_dof_relocate() */ /* * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated * header: it should be at the front of a memory region that is at least * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in * size. It need not be validated in any other way. */ static int dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr, dtrace_enabling_t **enabp, uint64_t ubase, int noprobes) { #pragma unused(ubase) /* __APPLE__ */ uint64_t len = dof->dofh_loadsz, seclen; uintptr_t daddr = (uintptr_t)dof; dtrace_ecbdesc_t *ep; dtrace_enabling_t *enab; uint_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t)); /* * Check the DOF header identification bytes. In addition to checking * valid settings, we also verify that unused bits/bytes are zeroed so * we can use them later without fear of regressing existing binaries. */ if (bcmp(&dof->dofh_ident[DOF_ID_MAG0], DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) { dtrace_dof_error(dof, "DOF magic string mismatch"); return (-1); } if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 && dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) { dtrace_dof_error(dof, "DOF has invalid data model"); return (-1); } if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) { dtrace_dof_error(dof, "DOF encoding mismatch"); return (-1); } /* * APPLE NOTE: Darwin only supports DOF_VERSION_3 for now. */ if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_3) { dtrace_dof_error(dof, "DOF version mismatch"); return (-1); } if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) { dtrace_dof_error(dof, "DOF uses unsupported instruction set"); return (-1); } if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) { dtrace_dof_error(dof, "DOF uses too many integer registers"); return (-1); } if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) { dtrace_dof_error(dof, "DOF uses too many tuple registers"); return (-1); } for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) { if (dof->dofh_ident[i] != 0) { dtrace_dof_error(dof, "DOF has invalid ident byte set"); return (-1); } } if (dof->dofh_flags & ~DOF_FL_VALID) { dtrace_dof_error(dof, "DOF has invalid flag bits set"); return (-1); } if (dof->dofh_secsize == 0) { dtrace_dof_error(dof, "zero section header size"); return (-1); } /* * Check that the section headers don't exceed the amount of DOF * data. Note that we cast the section size and number of sections * to uint64_t's to prevent possible overflow in the multiplication. */ seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize; if (dof->dofh_secoff > len || seclen > len || dof->dofh_secoff + seclen > len) { dtrace_dof_error(dof, "truncated section headers"); return (-1); } if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) { dtrace_dof_error(dof, "misaligned section headers"); return (-1); } if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) { dtrace_dof_error(dof, "misaligned section size"); return (-1); } /* * Take an initial pass through the section headers to be sure that * the headers don't have stray offsets. If the 'noprobes' flag is * set, do not permit sections relating to providers, probes, or args. */ for (i = 0; i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)(daddr + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); if (noprobes) { switch (sec->dofs_type) { case DOF_SECT_PROVIDER: case DOF_SECT_PROBES: case DOF_SECT_PRARGS: case DOF_SECT_PROFFS: dtrace_dof_error(dof, "illegal sections " "for enabling"); return (-1); } } if (!(sec->dofs_flags & DOF_SECF_LOAD)) continue; /* just ignore non-loadable sections */ if (sec->dofs_align & (sec->dofs_align - 1)) { dtrace_dof_error(dof, "bad section alignment"); return (-1); } if (sec->dofs_offset & (sec->dofs_align - 1)) { dtrace_dof_error(dof, "misaligned section"); return (-1); } if (sec->dofs_offset > len || sec->dofs_size > len || sec->dofs_offset + sec->dofs_size > len) { dtrace_dof_error(dof, "corrupt section header"); return (-1); } if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr + sec->dofs_offset + sec->dofs_size - 1) != '\0') { dtrace_dof_error(dof, "non-terminating string table"); return (-1); } } /* * APPLE NOTE: We have no further relocation to perform. * All dof values are relative offsets. */ if ((enab = *enabp) == NULL) enab = *enabp = dtrace_enabling_create(vstate); for (i = 0; i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)(daddr + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); if (sec->dofs_type != DOF_SECT_ECBDESC) continue; /* * APPLE NOTE: Defend against gcc 4.0 botch on x86. * not all paths out of inlined dtrace_dof_ecbdesc * are checked for the NULL return value. * Check for NULL explicitly here. */ ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr); if (ep == NULL) { dtrace_enabling_destroy(enab); *enabp = NULL; return (-1); } dtrace_enabling_add(enab, ep); } return (0); } /* * Process DOF for any options. This routine assumes that the DOF has been * at least processed by dtrace_dof_slurp(). */ static int dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state) { uint_t i; int rval; uint32_t entsize; size_t offs; dof_optdesc_t *desc; for (i = 0; i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof + (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize); if (sec->dofs_type != DOF_SECT_OPTDESC) continue; if (sec->dofs_align != sizeof (uint64_t)) { dtrace_dof_error(dof, "bad alignment in " "option description"); return (EINVAL); } if ((entsize = sec->dofs_entsize) == 0) { dtrace_dof_error(dof, "zeroed option entry size"); return (EINVAL); } if (entsize < sizeof (dof_optdesc_t)) { dtrace_dof_error(dof, "bad option entry size"); return (EINVAL); } for (offs = 0; offs < sec->dofs_size; offs += entsize) { desc = (dof_optdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset + offs); if (desc->dofo_strtab != DOF_SECIDX_NONE) { dtrace_dof_error(dof, "non-zero option string"); return (EINVAL); } if (desc->dofo_value == (uint64_t)DTRACEOPT_UNSET) { dtrace_dof_error(dof, "unset option"); return (EINVAL); } if ((rval = dtrace_state_option(state, desc->dofo_option, desc->dofo_value)) != 0) { dtrace_dof_error(dof, "rejected option"); return (rval); } } } return (0); } /* * DTrace Consumer State Functions */ static int dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size) { size_t hashsize, maxper, min_size, chunksize = dstate->dtds_chunksize; void *base; uintptr_t limit; dtrace_dynvar_t *dvar, *next, *start; size_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL); bzero(dstate, sizeof (dtrace_dstate_t)); if ((dstate->dtds_chunksize = chunksize) == 0) dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE; if (size < (min_size = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t))) size = min_size; if ((base = kmem_zalloc(size, KM_NOSLEEP)) == NULL) return (ENOMEM); dstate->dtds_size = size; dstate->dtds_base = base; dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP); bzero(dstate->dtds_percpu, (int)NCPU * sizeof (dtrace_dstate_percpu_t)); hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)); if (hashsize != 1 && (hashsize & 1)) hashsize--; dstate->dtds_hashsize = hashsize; dstate->dtds_hash = dstate->dtds_base; /* * Set all of our hash buckets to point to the single sink, and (if * it hasn't already been set), set the sink's hash value to be the * sink sentinel value. The sink is needed for dynamic variable * lookups to know that they have iterated over an entire, valid hash * chain. */ for (i = 0; i < hashsize; i++) dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink; if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK) dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK; /* * Determine number of active CPUs. Divide free list evenly among * active CPUs. */ start = (dtrace_dynvar_t *) ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t)); limit = (uintptr_t)base + size; maxper = (limit - (uintptr_t)start) / (int)NCPU; maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize; for (i = 0; i < NCPU; i++) { dstate->dtds_percpu[i].dtdsc_free = dvar = start; /* * If we don't even have enough chunks to make it once through * NCPUs, we're just going to allocate everything to the first * CPU. And if we're on the last CPU, we're going to allocate * whatever is left over. In either case, we set the limit to * be the limit of the dynamic variable space. */ if (maxper == 0 || i == NCPU - 1) { limit = (uintptr_t)base + size; start = NULL; } else { limit = (uintptr_t)start + maxper; start = (dtrace_dynvar_t *)limit; } ASSERT(limit <= (uintptr_t)base + size); for (;;) { next = (dtrace_dynvar_t *)((uintptr_t)dvar + dstate->dtds_chunksize); if ((uintptr_t)next + dstate->dtds_chunksize >= limit) break; dvar->dtdv_next = next; dvar = next; } if (maxper == 0) break; } return (0); } static void dtrace_dstate_fini(dtrace_dstate_t *dstate) { lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); if (dstate->dtds_base == NULL) return; kmem_free(dstate->dtds_base, dstate->dtds_size); kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu); } static void dtrace_vstate_fini(dtrace_vstate_t *vstate) { /* * Logical XOR, where are you? */ ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL)); if (vstate->dtvs_nglobals > 0) { kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals * sizeof (dtrace_statvar_t *)); } if (vstate->dtvs_ntlocals > 0) { kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals * sizeof (dtrace_difv_t)); } ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL)); if (vstate->dtvs_nlocals > 0) { kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals * sizeof (dtrace_statvar_t *)); } } static void dtrace_state_clean(dtrace_state_t *state) { if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) return; dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars); dtrace_speculation_clean(state); } static void dtrace_state_deadman(dtrace_state_t *state) { hrtime_t now; dtrace_sync(); now = dtrace_gethrtime(); if (state != dtrace_anon.dta_state && now - state->dts_laststatus >= dtrace_deadman_user) return; /* * We must be sure that dts_alive never appears to be less than the * value upon entry to dtrace_state_deadman(), and because we lack a * dtrace_cas64(), we cannot store to it atomically. We thus instead * store INT64_MAX to it, followed by a memory barrier, followed by * the new value. This assures that dts_alive never appears to be * less than its true value, regardless of the order in which the * stores to the underlying storage are issued. */ state->dts_alive = INT64_MAX; dtrace_membar_producer(); state->dts_alive = now; } static int dtrace_state_create(dev_t *devp, cred_t *cr, dtrace_state_t **new_state) { minor_t minor; major_t major; char c[30]; dtrace_state_t *state; dtrace_optval_t *opt; int bufsize = (int)NCPU * sizeof (dtrace_buffer_t), i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); /* Cause restart */ *new_state = NULL; /* * Darwin's DEVFS layer acquired the minor number for this "device" when it called * dtrace_devfs_clone_func(). At that time, dtrace_devfs_clone_func() proposed a minor number * (next unused according to vmem_alloc()) and then immediately put the number back in play * (by calling vmem_free()). Now that minor number is being used for an open, so committing it * to use. The following vmem_alloc() must deliver that same minor number. FIXME. */ minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1, VM_BESTFIT | VM_SLEEP); if (NULL != devp) { ASSERT(getminor(*devp) == minor); if (getminor(*devp) != minor) { printf("dtrace_open: couldn't re-acquire vended minor number %d. Instead got %d\n", getminor(*devp), minor); vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1); return (ERESTART); /* can't reacquire */ } } else { /* NULL==devp iff "Anonymous state" (see dtrace_anon_property), * so just vend the minor device number here de novo since no "open" has occurred. */ } if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) { vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1); return (EAGAIN); /* temporary resource shortage */ } state = ddi_get_soft_state(dtrace_softstate, minor); state->dts_epid = DTRACE_EPIDNONE + 1; (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", minor); state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1, NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER); if (devp != NULL) { major = getemajor(*devp); } else { major = ddi_driver_major(dtrace_devi); } state->dts_dev = makedevice(major, minor); if (devp != NULL) *devp = state->dts_dev; /* * We allocate NCPU buffers. On the one hand, this can be quite * a bit of memory per instance (nearly 36K on a Starcat). On the * other hand, it saves an additional memory reference in the probe * path. */ state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP); state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP); state->dts_cleaner = CYCLIC_NONE; state->dts_deadman = CYCLIC_NONE; state->dts_vstate.dtvs_state = state; for (i = 0; i < DTRACEOPT_MAX; i++) state->dts_options[i] = DTRACEOPT_UNSET; /* * Set the default options. */ opt = state->dts_options; opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH; opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO; opt[DTRACEOPT_NSPEC] = dtrace_nspec_default; opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default; opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL; opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default; opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default; opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default; opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default; opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default; opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default; opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default; opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default; opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default; state->dts_activity = DTRACE_ACTIVITY_INACTIVE; /* * Depending on the user credentials, we set flag bits which alter probe * visibility or the amount of destructiveness allowed. In the case of * actual anonymous tracing, or the possession of all privileges, all of * the normal checks are bypassed. */ if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) { state->dts_cred.dcr_visible = DTRACE_CRV_ALL; state->dts_cred.dcr_action = DTRACE_CRA_ALL; } else { /* * Set up the credentials for this instantiation. We take a * hold on the credential to prevent it from disappearing on * us; this in turn prevents the zone_t referenced by this * credential from disappearing. This means that we can * examine the credential and the zone from probe context. */ crhold(cr); state->dts_cred.dcr_cred = cr; /* * CRA_PROC means "we have *some* privilege for dtrace" and * unlocks the use of variables like pid, zonename, etc. */ if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) || PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) { state->dts_cred.dcr_action |= DTRACE_CRA_PROC; } /* * dtrace_user allows use of syscall and profile providers. * If the user also has proc_owner and/or proc_zone, we * extend the scope to include additional visibility and * destructive power. */ if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) { if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) { state->dts_cred.dcr_visible |= DTRACE_CRV_ALLPROC; state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; } if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) { state->dts_cred.dcr_visible |= DTRACE_CRV_ALLZONE; state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; } /* * If we have all privs in whatever zone this is, * we can do destructive things to processes which * have altered credentials. * * APPLE NOTE: Darwin doesn't do zones. * Behave as if zone always has destructive privs. */ state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG; } /* * Holding the dtrace_kernel privilege also implies that * the user has the dtrace_user privilege from a visibility * perspective. But without further privileges, some * destructive actions are not available. */ if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) { /* * Make all probes in all zones visible. However, * this doesn't mean that all actions become available * to all zones. */ state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL | DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE; state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL | DTRACE_CRA_PROC; /* * Holding proc_owner means that destructive actions * for *this* zone are allowed. */ if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; /* * Holding proc_zone means that destructive actions * for this user/group ID in all zones is allowed. */ if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; /* * If we have all privs in whatever zone this is, * we can do destructive things to processes which * have altered credentials. * * APPLE NOTE: Darwin doesn't do zones. * Behave as if zone always has destructive privs. */ state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG; } /* * Holding the dtrace_proc privilege gives control over fasttrap * and pid providers. We need to grant wider destructive * privileges in the event that the user has proc_owner and/or * proc_zone. */ if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) { if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER; if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) state->dts_cred.dcr_action |= DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE; } } *new_state = state; return(0); /* Success */ } static int dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which) { dtrace_optval_t *opt = state->dts_options, size; processorid_t cpu = 0; int flags = 0, rval; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); ASSERT(which < DTRACEOPT_MAX); ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE || (state == dtrace_anon.dta_state && state->dts_activity == DTRACE_ACTIVITY_ACTIVE)); if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0) return (0); if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET) cpu = opt[DTRACEOPT_CPU]; if (which == DTRACEOPT_SPECSIZE) flags |= DTRACEBUF_NOSWITCH; if (which == DTRACEOPT_BUFSIZE) { if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING) flags |= DTRACEBUF_RING; if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL) flags |= DTRACEBUF_FILL; if (state != dtrace_anon.dta_state || state->dts_activity != DTRACE_ACTIVITY_ACTIVE) flags |= DTRACEBUF_INACTIVE; } for (size = opt[which]; (size_t)size >= sizeof (uint64_t); size >>= 1) { /* * The size must be 8-byte aligned. If the size is not 8-byte * aligned, drop it down by the difference. */ if (size & (sizeof (uint64_t) - 1)) size -= size & (sizeof (uint64_t) - 1); if (size < state->dts_reserve) { /* * Buffers always must be large enough to accommodate * their prereserved space. We return E2BIG instead * of ENOMEM in this case to allow for user-level * software to differentiate the cases. */ return (E2BIG); } rval = dtrace_buffer_alloc(buf, size, flags, cpu); if (rval != ENOMEM) { opt[which] = size; return (rval); } if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL) return (rval); } return (ENOMEM); } static int dtrace_state_buffers(dtrace_state_t *state) { dtrace_speculation_t *spec = state->dts_speculations; int rval, i; if ((rval = dtrace_state_buffer(state, state->dts_buffer, DTRACEOPT_BUFSIZE)) != 0) return (rval); if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer, DTRACEOPT_AGGSIZE)) != 0) return (rval); for (i = 0; i < state->dts_nspeculations; i++) { if ((rval = dtrace_state_buffer(state, spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0) return (rval); } return (0); } static void dtrace_state_prereserve(dtrace_state_t *state) { dtrace_ecb_t *ecb; dtrace_probe_t *probe; state->dts_reserve = 0; if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL) return; /* * If our buffer policy is a "fill" buffer policy, we need to set the * prereserved space to be the space required by the END probes. */ probe = dtrace_probes[dtrace_probeid_end - 1]; ASSERT(probe != NULL); for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) { if (ecb->dte_state != state) continue; state->dts_reserve += ecb->dte_needed + ecb->dte_alignment; } } static int dtrace_state_go(dtrace_state_t *state, processorid_t *cpu) { dtrace_optval_t *opt = state->dts_options, sz, nspec; dtrace_speculation_t *spec; dtrace_buffer_t *buf; cyc_handler_t hdlr; cyc_time_t when; int rval = 0, i, bufsize = (int)NCPU * sizeof (dtrace_buffer_t); dtrace_icookie_t cookie; lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_lock); if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) { rval = EBUSY; goto out; } /* * Before we can perform any checks, we must prime all of the * retained enablings that correspond to this state. */ dtrace_enabling_prime(state); if (state->dts_destructive && !state->dts_cred.dcr_destructive) { rval = EACCES; goto out; } dtrace_state_prereserve(state); /* * Now we want to do is try to allocate our speculations. * We do not automatically resize the number of speculations; if * this fails, we will fail the operation. */ nspec = opt[DTRACEOPT_NSPEC]; ASSERT(nspec != DTRACEOPT_UNSET); if (nspec > INT_MAX) { rval = ENOMEM; goto out; } spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t), KM_NOSLEEP); if (spec == NULL) { rval = ENOMEM; goto out; } state->dts_speculations = spec; state->dts_nspeculations = (int)nspec; for (i = 0; i < nspec; i++) { if ((buf = kmem_zalloc(bufsize, KM_NOSLEEP)) == NULL) { rval = ENOMEM; goto err; } spec[i].dtsp_buffer = buf; } if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) { if (dtrace_anon.dta_state == NULL) { rval = ENOENT; goto out; } if (state->dts_necbs != 0) { rval = EALREADY; goto out; } state->dts_anon = dtrace_anon_grab(); ASSERT(state->dts_anon != NULL); state = state->dts_anon; /* * We want "grabanon" to be set in the grabbed state, so we'll * copy that option value from the grabbing state into the * grabbed state. */ state->dts_options[DTRACEOPT_GRABANON] = opt[DTRACEOPT_GRABANON]; *cpu = dtrace_anon.dta_beganon; /* * If the anonymous state is active (as it almost certainly * is if the anonymous enabling ultimately matched anything), * we don't allow any further option processing -- but we * don't return failure. */ if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) goto out; } if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET && opt[DTRACEOPT_AGGSIZE] != 0) { if (state->dts_aggregations == NULL) { /* * We're not going to create an aggregation buffer * because we don't have any ECBs that contain * aggregations -- set this option to 0. */ opt[DTRACEOPT_AGGSIZE] = 0; } else { /* * If we have an aggregation buffer, we must also have * a buffer to use as scratch. */ if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET || (size_t)opt[DTRACEOPT_BUFSIZE] < state->dts_needed) { opt[DTRACEOPT_BUFSIZE] = state->dts_needed; } } } if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET && opt[DTRACEOPT_SPECSIZE] != 0) { if (!state->dts_speculates) { /* * We're not going to create speculation buffers * because we don't have any ECBs that actually * speculate -- set the speculation size to 0. */ opt[DTRACEOPT_SPECSIZE] = 0; } } /* * The bare minimum size for any buffer that we're actually going to * do anything to is sizeof (uint64_t). */ sz = sizeof (uint64_t); if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) || (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) || (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) { /* * A buffer size has been explicitly set to 0 (or to a size * that will be adjusted to 0) and we need the space -- we * need to return failure. We return ENOSPC to differentiate * it from failing to allocate a buffer due to failure to meet * the reserve (for which we return E2BIG). */ rval = ENOSPC; goto out; } if ((rval = dtrace_state_buffers(state)) != 0) goto err; if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET) sz = dtrace_dstate_defsize; do { rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz); if (rval == 0) break; if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL) goto err; } while (sz >>= 1); opt[DTRACEOPT_DYNVARSIZE] = sz; if (rval != 0) goto err; if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max) opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max; if (opt[DTRACEOPT_CLEANRATE] == 0) opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max; if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min) opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min; if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max) opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max; hdlr.cyh_func = (cyc_func_t)dtrace_state_clean; hdlr.cyh_arg = state; hdlr.cyh_level = CY_LOW_LEVEL; when.cyt_when = 0; when.cyt_interval = opt[DTRACEOPT_CLEANRATE]; state->dts_cleaner = cyclic_add(&hdlr, &when); hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman; hdlr.cyh_arg = state; hdlr.cyh_level = CY_LOW_LEVEL; when.cyt_when = 0; when.cyt_interval = dtrace_deadman_interval; state->dts_alive = state->dts_laststatus = dtrace_gethrtime(); state->dts_deadman = cyclic_add(&hdlr, &when); state->dts_activity = DTRACE_ACTIVITY_WARMUP; /* * Now it's time to actually fire the BEGIN probe. We need to disable * interrupts here both to record the CPU on which we fired the BEGIN * probe (the data from this CPU will be processed first at user * level) and to manually activate the buffer for this CPU. */ cookie = dtrace_interrupt_disable(); *cpu = CPU->cpu_id; ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE); state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE; dtrace_probe(dtrace_probeid_begin, (uint64_t)(uintptr_t)state, 0, 0, 0, 0); dtrace_interrupt_enable(cookie); /* * We may have had an exit action from a BEGIN probe; only change our * state to ACTIVE if we're still in WARMUP. */ ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP || state->dts_activity == DTRACE_ACTIVITY_DRAINING); if (state->dts_activity == DTRACE_ACTIVITY_WARMUP) state->dts_activity = DTRACE_ACTIVITY_ACTIVE; /* * Regardless of whether or not now we're in ACTIVE or DRAINING, we * want each CPU to transition its principal buffer out of the * INACTIVE state. Doing this assures that no CPU will suddenly begin * processing an ECB halfway down a probe's ECB chain; all CPUs will * atomically transition from processing none of a state's ECBs to * processing all of them. */ dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_buffer_activate, state); goto out; err: dtrace_buffer_free(state->dts_buffer); dtrace_buffer_free(state->dts_aggbuffer); if ((nspec = state->dts_nspeculations) == 0) { ASSERT(state->dts_speculations == NULL); goto out; } spec = state->dts_speculations; ASSERT(spec != NULL); for (i = 0; i < state->dts_nspeculations; i++) { if ((buf = spec[i].dtsp_buffer) == NULL) break; dtrace_buffer_free(buf); kmem_free(buf, bufsize); } kmem_free(spec, nspec * sizeof (dtrace_speculation_t)); state->dts_nspeculations = 0; state->dts_speculations = NULL; out: lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); return (rval); } static int dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu) { dtrace_icookie_t cookie; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE && state->dts_activity != DTRACE_ACTIVITY_DRAINING) return (EINVAL); /* * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync * to be sure that every CPU has seen it. See below for the details * on why this is done. */ state->dts_activity = DTRACE_ACTIVITY_DRAINING; dtrace_sync(); /* * By this point, it is impossible for any CPU to be still processing * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe() * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN * iff we're in the END probe. */ state->dts_activity = DTRACE_ACTIVITY_COOLDOWN; dtrace_sync(); ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN); /* * Finally, we can release the reserve and call the END probe. We * disable interrupts across calling the END probe to allow us to * return the CPU on which we actually called the END probe. This * allows user-land to be sure that this CPU's principal buffer is * processed last. */ state->dts_reserve = 0; cookie = dtrace_interrupt_disable(); *cpu = CPU->cpu_id; dtrace_probe(dtrace_probeid_end, (uint64_t)(uintptr_t)state, 0, 0, 0, 0); dtrace_interrupt_enable(cookie); state->dts_activity = DTRACE_ACTIVITY_STOPPED; dtrace_sync(); return (0); } static int dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option, dtrace_optval_t val) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) return (EBUSY); if (option >= DTRACEOPT_MAX) return (EINVAL); if (option != DTRACEOPT_CPU && val < 0) return (EINVAL); switch (option) { case DTRACEOPT_DESTRUCTIVE: /* * Prevent consumers from enabling destructive actions if DTrace * is running in a restricted environment, or if actions are * disallowed. */ if (dtrace_is_restricted() || dtrace_destructive_disallow) return (EACCES); state->dts_cred.dcr_destructive = 1; break; case DTRACEOPT_BUFSIZE: case DTRACEOPT_DYNVARSIZE: case DTRACEOPT_AGGSIZE: case DTRACEOPT_SPECSIZE: case DTRACEOPT_STRSIZE: if (val < 0) return (EINVAL); if (val >= LONG_MAX) { /* * If this is an otherwise negative value, set it to * the highest multiple of 128m less than LONG_MAX. * Technically, we're adjusting the size without * regard to the buffer resizing policy, but in fact, * this has no effect -- if we set the buffer size to * ~LONG_MAX and the buffer policy is ultimately set to * be "manual", the buffer allocation is guaranteed to * fail, if only because the allocation requires two * buffers. (We set the the size to the highest * multiple of 128m because it ensures that the size * will remain a multiple of a megabyte when * repeatedly halved -- all the way down to 15m.) */ val = LONG_MAX - (1 << 27) + 1; } } state->dts_options[option] = val; return (0); } static void dtrace_state_destroy(dtrace_state_t *state) { dtrace_ecb_t *ecb; dtrace_vstate_t *vstate = &state->dts_vstate; minor_t minor = getminor(state->dts_dev); int i, bufsize = (int)NCPU * sizeof (dtrace_buffer_t); dtrace_speculation_t *spec = state->dts_speculations; int nspec = state->dts_nspeculations; uint32_t match; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); /* * First, retract any retained enablings for this state. */ dtrace_enabling_retract(state); ASSERT(state->dts_nretained == 0); if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE || state->dts_activity == DTRACE_ACTIVITY_DRAINING) { /* * We have managed to come into dtrace_state_destroy() on a * hot enabling -- almost certainly because of a disorderly * shutdown of a consumer. (That is, a consumer that is * exiting without having called dtrace_stop().) In this case, * we're going to set our activity to be KILLED, and then * issue a sync to be sure that everyone is out of probe * context before we start blowing away ECBs. */ state->dts_activity = DTRACE_ACTIVITY_KILLED; dtrace_sync(); } /* * Release the credential hold we took in dtrace_state_create(). */ if (state->dts_cred.dcr_cred != NULL) crfree(state->dts_cred.dcr_cred); /* * Now we can safely disable and destroy any enabled probes. Because * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress * (especially if they're all enabled), we take two passes through the * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and * in the second we disable whatever is left over. */ for (match = DTRACE_PRIV_KERNEL; ; match = 0) { for (i = 0; i < state->dts_necbs; i++) { if ((ecb = state->dts_ecbs[i]) == NULL) continue; if (match && ecb->dte_probe != NULL) { dtrace_probe_t *probe = ecb->dte_probe; dtrace_provider_t *prov = probe->dtpr_provider; if (!(prov->dtpv_priv.dtpp_flags & match)) continue; } dtrace_ecb_disable(ecb); dtrace_ecb_destroy(ecb); } if (!match) break; } /* * Before we free the buffers, perform one more sync to assure that * every CPU is out of probe context. */ dtrace_sync(); dtrace_buffer_free(state->dts_buffer); dtrace_buffer_free(state->dts_aggbuffer); for (i = 0; i < nspec; i++) dtrace_buffer_free(spec[i].dtsp_buffer); if (state->dts_cleaner != CYCLIC_NONE) cyclic_remove(state->dts_cleaner); if (state->dts_deadman != CYCLIC_NONE) cyclic_remove(state->dts_deadman); dtrace_dstate_fini(&vstate->dtvs_dynvars); dtrace_vstate_fini(vstate); kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *)); if (state->dts_aggregations != NULL) { #if DEBUG for (i = 0; i < state->dts_naggregations; i++) ASSERT(state->dts_aggregations[i] == NULL); #endif ASSERT(state->dts_naggregations > 0); kmem_free(state->dts_aggregations, state->dts_naggregations * sizeof (dtrace_aggregation_t *)); } kmem_free(state->dts_buffer, bufsize); kmem_free(state->dts_aggbuffer, bufsize); for (i = 0; i < nspec; i++) kmem_free(spec[i].dtsp_buffer, bufsize); kmem_free(spec, nspec * sizeof (dtrace_speculation_t)); dtrace_format_destroy(state); vmem_destroy(state->dts_aggid_arena); ddi_soft_state_free(dtrace_softstate, minor); vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1); } /* * DTrace Anonymous Enabling Functions */ static dtrace_state_t * dtrace_anon_grab(void) { dtrace_state_t *state; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if ((state = dtrace_anon.dta_state) == NULL) { ASSERT(dtrace_anon.dta_enabling == NULL); return (NULL); } ASSERT(dtrace_anon.dta_enabling != NULL); ASSERT(dtrace_retained != NULL); dtrace_enabling_destroy(dtrace_anon.dta_enabling); dtrace_anon.dta_enabling = NULL; dtrace_anon.dta_state = NULL; return (state); } static void dtrace_anon_property(void) { int i, rv; dtrace_state_t *state; dof_hdr_t *dof; char c[32]; /* enough for "dof-data-" + digits */ lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); for (i = 0; ; i++) { (void) snprintf(c, sizeof (c), "dof-data-%d", i); dtrace_err_verbose = 1; if ((dof = dtrace_dof_property(c)) == NULL) { dtrace_err_verbose = 0; break; } /* * We want to create anonymous state, so we need to transition * the kernel debugger to indicate that DTrace is active. If * this fails (e.g. because the debugger has modified text in * some way), we won't continue with the processing. */ if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) { cmn_err(CE_NOTE, "kernel debugger active; anonymous " "enabling ignored."); dtrace_dof_destroy(dof); break; } /* * If we haven't allocated an anonymous state, we'll do so now. */ if ((state = dtrace_anon.dta_state) == NULL) { rv = dtrace_state_create(NULL, NULL, &state); dtrace_anon.dta_state = state; if (rv != 0 || state == NULL) { /* * This basically shouldn't happen: the only * failure mode from dtrace_state_create() is a * failure of ddi_soft_state_zalloc() that * itself should never happen. Still, the * interface allows for a failure mode, and * we want to fail as gracefully as possible: * we'll emit an error message and cease * processing anonymous state in this case. */ cmn_err(CE_WARN, "failed to create " "anonymous state"); dtrace_dof_destroy(dof); break; } } rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(), &dtrace_anon.dta_enabling, 0, B_TRUE); if (rv == 0) rv = dtrace_dof_options(dof, state); dtrace_err_verbose = 0; dtrace_dof_destroy(dof); if (rv != 0) { /* * This is malformed DOF; chuck any anonymous state * that we created. */ ASSERT(dtrace_anon.dta_enabling == NULL); dtrace_state_destroy(state); dtrace_anon.dta_state = NULL; break; } ASSERT(dtrace_anon.dta_enabling != NULL); } if (dtrace_anon.dta_enabling != NULL) { int rval; /* * dtrace_enabling_retain() can only fail because we are * trying to retain more enablings than are allowed -- but * we only have one anonymous enabling, and we are guaranteed * to be allowed at least one retained enabling; we assert * that dtrace_enabling_retain() returns success. */ rval = dtrace_enabling_retain(dtrace_anon.dta_enabling); ASSERT(rval == 0); dtrace_enabling_dump(dtrace_anon.dta_enabling); } } /* * DTrace Helper Functions */ static void dtrace_helper_trace(dtrace_helper_action_t *helper, dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where) { uint32_t size, next, nnext; int i; dtrace_helptrace_t *ent; uint16_t flags = cpu_core[CPU->cpu_id].cpuc_dtrace_flags; if (!dtrace_helptrace_enabled) return; ASSERT((uint32_t)vstate->dtvs_nlocals <= dtrace_helptrace_nlocals); /* * What would a tracing framework be without its own tracing * framework? (Well, a hell of a lot simpler, for starters...) */ size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals * sizeof (uint64_t) - sizeof (uint64_t); /* * Iterate until we can allocate a slot in the trace buffer. */ do { next = dtrace_helptrace_next; if (next + size < dtrace_helptrace_bufsize) { nnext = next + size; } else { nnext = size; } } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next); /* * We have our slot; fill it in. */ if (nnext == size) next = 0; ent = (dtrace_helptrace_t *)&dtrace_helptrace_buffer[next]; ent->dtht_helper = helper; ent->dtht_where = where; ent->dtht_nlocals = vstate->dtvs_nlocals; ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ? mstate->dtms_fltoffs : -1; ent->dtht_fault = DTRACE_FLAGS2FLT(flags); ent->dtht_illval = cpu_core[CPU->cpu_id].cpuc_dtrace_illval; for (i = 0; i < vstate->dtvs_nlocals; i++) { dtrace_statvar_t *svar; if ((svar = vstate->dtvs_locals[i]) == NULL) continue; ASSERT(svar->dtsv_size >= (int)NCPU * sizeof (uint64_t)); ent->dtht_locals[i] = ((uint64_t *)(uintptr_t)svar->dtsv_data)[CPU->cpu_id]; } } static uint64_t dtrace_helper(int which, dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t arg0, uint64_t arg1) { uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; uint64_t sarg0 = mstate->dtms_arg[0]; uint64_t sarg1 = mstate->dtms_arg[1]; uint64_t rval = 0; dtrace_helpers_t *helpers = curproc->p_dtrace_helpers; dtrace_helper_action_t *helper; dtrace_vstate_t *vstate; dtrace_difo_t *pred; int i, trace = dtrace_helptrace_enabled; ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS); if (helpers == NULL) return (0); if ((helper = helpers->dthps_actions[which]) == NULL) return (0); vstate = &helpers->dthps_vstate; mstate->dtms_arg[0] = arg0; mstate->dtms_arg[1] = arg1; /* * Now iterate over each helper. If its predicate evaluates to 'true', * we'll call the corresponding actions. Note that the below calls * to dtrace_dif_emulate() may set faults in machine state. This is * okay: our caller (the outer dtrace_dif_emulate()) will simply plow * the stored DIF offset with its own (which is the desired behavior). * Also, note the calls to dtrace_dif_emulate() may allocate scratch * from machine state; this is okay, too. */ for (; helper != NULL; helper = helper->dtha_next) { if ((pred = helper->dtha_predicate) != NULL) { if (trace) dtrace_helper_trace(helper, mstate, vstate, 0); if (!dtrace_dif_emulate(pred, mstate, vstate, state)) goto next; if (*flags & CPU_DTRACE_FAULT) goto err; } for (i = 0; i < helper->dtha_nactions; i++) { if (trace) dtrace_helper_trace(helper, mstate, vstate, i + 1); rval = dtrace_dif_emulate(helper->dtha_actions[i], mstate, vstate, state); if (*flags & CPU_DTRACE_FAULT) goto err; } next: if (trace) dtrace_helper_trace(helper, mstate, vstate, DTRACE_HELPTRACE_NEXT); } if (trace) dtrace_helper_trace(helper, mstate, vstate, DTRACE_HELPTRACE_DONE); /* * Restore the arg0 that we saved upon entry. */ mstate->dtms_arg[0] = sarg0; mstate->dtms_arg[1] = sarg1; return (rval); err: if (trace) dtrace_helper_trace(helper, mstate, vstate, DTRACE_HELPTRACE_ERR); /* * Restore the arg0 that we saved upon entry. */ mstate->dtms_arg[0] = sarg0; mstate->dtms_arg[1] = sarg1; return (0); } static void dtrace_helper_action_destroy(dtrace_helper_action_t *helper, dtrace_vstate_t *vstate) { int i; if (helper->dtha_predicate != NULL) dtrace_difo_release(helper->dtha_predicate, vstate); for (i = 0; i < helper->dtha_nactions; i++) { ASSERT(helper->dtha_actions[i] != NULL); dtrace_difo_release(helper->dtha_actions[i], vstate); } kmem_free(helper->dtha_actions, helper->dtha_nactions * sizeof (dtrace_difo_t *)); kmem_free(helper, sizeof (dtrace_helper_action_t)); } static int dtrace_helper_destroygen(proc_t* p, int gen) { dtrace_helpers_t *help = p->p_dtrace_helpers; dtrace_vstate_t *vstate; uint_t i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if (help == NULL || gen > help->dthps_generation) return (EINVAL); vstate = &help->dthps_vstate; for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { dtrace_helper_action_t *last = NULL, *h, *next; for (h = help->dthps_actions[i]; h != NULL; h = next) { next = h->dtha_next; if (h->dtha_generation == gen) { if (last != NULL) { last->dtha_next = next; } else { help->dthps_actions[i] = next; } dtrace_helper_action_destroy(h, vstate); } else { last = h; } } } /* * Interate until we've cleared out all helper providers with the * given generation number. */ for (;;) { dtrace_helper_provider_t *prov = NULL; /* * Look for a helper provider with the right generation. We * have to start back at the beginning of the list each time * because we drop dtrace_lock. It's unlikely that we'll make * more than two passes. */ for (i = 0; i < help->dthps_nprovs; i++) { prov = help->dthps_provs[i]; if (prov->dthp_generation == gen) break; } /* * If there were no matches, we're done. */ if (i == help->dthps_nprovs) break; /* * Move the last helper provider into this slot. */ help->dthps_nprovs--; help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs]; help->dthps_provs[help->dthps_nprovs] = NULL; lck_mtx_unlock(&dtrace_lock); /* * If we have a meta provider, remove this helper provider. */ lck_mtx_lock(&dtrace_meta_lock); if (dtrace_meta_pid != NULL) { ASSERT(dtrace_deferred_pid == NULL); dtrace_helper_provider_remove(&prov->dthp_prov, p->p_pid); } lck_mtx_unlock(&dtrace_meta_lock); dtrace_helper_provider_destroy(prov); lck_mtx_lock(&dtrace_lock); } return (0); } static int dtrace_helper_validate(dtrace_helper_action_t *helper) { int err = 0, i; dtrace_difo_t *dp; if ((dp = helper->dtha_predicate) != NULL) err += dtrace_difo_validate_helper(dp); for (i = 0; i < helper->dtha_nactions; i++) err += dtrace_difo_validate_helper(helper->dtha_actions[i]); return (err == 0); } static int dtrace_helper_action_add(proc_t* p, int which, dtrace_ecbdesc_t *ep) { dtrace_helpers_t *help; dtrace_helper_action_t *helper, *last; dtrace_actdesc_t *act; dtrace_vstate_t *vstate; dtrace_predicate_t *pred; int count = 0, nactions = 0, i; if (which < 0 || which >= DTRACE_NHELPER_ACTIONS) return (EINVAL); help = p->p_dtrace_helpers; last = help->dthps_actions[which]; vstate = &help->dthps_vstate; for (count = 0; last != NULL; last = last->dtha_next) { count++; if (last->dtha_next == NULL) break; } /* * If we already have dtrace_helper_actions_max helper actions for this * helper action type, we'll refuse to add a new one. */ if (count >= dtrace_helper_actions_max) return (ENOSPC); helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP); helper->dtha_generation = help->dthps_generation; if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) { ASSERT(pred->dtp_difo != NULL); dtrace_difo_hold(pred->dtp_difo); helper->dtha_predicate = pred->dtp_difo; } for (act = ep->dted_action; act != NULL; act = act->dtad_next) { if (act->dtad_kind != DTRACEACT_DIFEXPR) goto err; if (act->dtad_difo == NULL) goto err; nactions++; } helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) * (helper->dtha_nactions = nactions), KM_SLEEP); for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) { dtrace_difo_hold(act->dtad_difo); helper->dtha_actions[i++] = act->dtad_difo; } if (!dtrace_helper_validate(helper)) goto err; if (last == NULL) { help->dthps_actions[which] = helper; } else { last->dtha_next = helper; } if ((uint32_t)vstate->dtvs_nlocals > dtrace_helptrace_nlocals) { dtrace_helptrace_nlocals = vstate->dtvs_nlocals; dtrace_helptrace_next = 0; } return (0); err: dtrace_helper_action_destroy(helper, vstate); return (EINVAL); } static void dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help, dof_helper_t *dofhp) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_NOTOWNED); lck_mtx_lock(&dtrace_meta_lock); lck_mtx_lock(&dtrace_lock); if (!dtrace_attached() || dtrace_meta_pid == NULL) { /* * If the dtrace module is loaded but not attached, or if * there aren't isn't a meta provider registered to deal with * these provider descriptions, we need to postpone creating * the actual providers until later. */ if (help->dthps_next == NULL && help->dthps_prev == NULL && dtrace_deferred_pid != help) { help->dthps_deferred = 1; help->dthps_pid = p->p_pid; help->dthps_next = dtrace_deferred_pid; help->dthps_prev = NULL; if (dtrace_deferred_pid != NULL) dtrace_deferred_pid->dthps_prev = help; dtrace_deferred_pid = help; } lck_mtx_unlock(&dtrace_lock); } else if (dofhp != NULL) { /* * If the dtrace module is loaded and we have a particular * helper provider description, pass that off to the * meta provider. */ lck_mtx_unlock(&dtrace_lock); dtrace_helper_provide(dofhp, p->p_pid); } else { /* * Otherwise, just pass all the helper provider descriptions * off to the meta provider. */ uint_t i; lck_mtx_unlock(&dtrace_lock); for (i = 0; i < help->dthps_nprovs; i++) { dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov, p->p_pid); } } lck_mtx_unlock(&dtrace_meta_lock); } static int dtrace_helper_provider_add(proc_t* p, dof_helper_t *dofhp, int gen) { dtrace_helpers_t *help; dtrace_helper_provider_t *hprov, **tmp_provs; uint_t tmp_maxprovs, i; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); help = p->p_dtrace_helpers; ASSERT(help != NULL); /* * If we already have dtrace_helper_providers_max helper providers, * we're refuse to add a new one. */ if (help->dthps_nprovs >= dtrace_helper_providers_max) return (ENOSPC); /* * Check to make sure this isn't a duplicate. */ for (i = 0; i < help->dthps_nprovs; i++) { if (dofhp->dofhp_addr == help->dthps_provs[i]->dthp_prov.dofhp_addr) return (EALREADY); } hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP); hprov->dthp_prov = *dofhp; hprov->dthp_ref = 1; hprov->dthp_generation = gen; /* * Allocate a bigger table for helper providers if it's already full. */ if (help->dthps_maxprovs == help->dthps_nprovs) { tmp_maxprovs = help->dthps_maxprovs; tmp_provs = help->dthps_provs; if (help->dthps_maxprovs == 0) help->dthps_maxprovs = 2; else help->dthps_maxprovs *= 2; if (help->dthps_maxprovs > dtrace_helper_providers_max) help->dthps_maxprovs = dtrace_helper_providers_max; ASSERT(tmp_maxprovs < help->dthps_maxprovs); help->dthps_provs = kmem_zalloc(help->dthps_maxprovs * sizeof (dtrace_helper_provider_t *), KM_SLEEP); if (tmp_provs != NULL) { bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs * sizeof (dtrace_helper_provider_t *)); kmem_free(tmp_provs, tmp_maxprovs * sizeof (dtrace_helper_provider_t *)); } } help->dthps_provs[help->dthps_nprovs] = hprov; help->dthps_nprovs++; return (0); } static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov) { lck_mtx_lock(&dtrace_lock); if (--hprov->dthp_ref == 0) { dof_hdr_t *dof; lck_mtx_unlock(&dtrace_lock); dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof; dtrace_dof_destroy(dof); kmem_free(hprov, sizeof (dtrace_helper_provider_t)); } else { lck_mtx_unlock(&dtrace_lock); } } static int dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec) { uintptr_t daddr = (uintptr_t)dof; dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec; dof_provider_t *provider; dof_probe_t *probe; uint8_t *arg; char *strtab, *typestr; dof_stridx_t typeidx; size_t typesz; uint_t nprobes, j, k; ASSERT(sec->dofs_type == DOF_SECT_PROVIDER); if (sec->dofs_offset & (sizeof (uint_t) - 1)) { dtrace_dof_error(dof, "misaligned section offset"); return (-1); } /* * The section needs to be large enough to contain the DOF provider * structure appropriate for the given version. */ if (sec->dofs_size < ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ? offsetof(dof_provider_t, dofpv_prenoffs) : sizeof (dof_provider_t))) { dtrace_dof_error(dof, "provider section too small"); return (-1); } provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset); str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab); prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes); arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs); off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs); if (str_sec == NULL || prb_sec == NULL || arg_sec == NULL || off_sec == NULL) return (-1); enoff_sec = NULL; if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 && provider->dofpv_prenoffs != DOF_SECT_NONE && (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS, provider->dofpv_prenoffs)) == NULL) return (-1); strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset); if (provider->dofpv_name >= str_sec->dofs_size || strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) { dtrace_dof_error(dof, "invalid provider name"); return (-1); } if (prb_sec->dofs_entsize == 0 || prb_sec->dofs_entsize > prb_sec->dofs_size) { dtrace_dof_error(dof, "invalid entry size"); return (-1); } if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) { dtrace_dof_error(dof, "misaligned entry size"); return (-1); } if (off_sec->dofs_entsize != sizeof (uint32_t)) { dtrace_dof_error(dof, "invalid entry size"); return (-1); } if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) { dtrace_dof_error(dof, "misaligned section offset"); return (-1); } if (arg_sec->dofs_entsize != sizeof (uint8_t)) { dtrace_dof_error(dof, "invalid entry size"); return (-1); } arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset); nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize; /* * Take a pass through the probes to check for errors. */ for (j = 0; j < nprobes; j++) { probe = (dof_probe_t *)(uintptr_t)(daddr + prb_sec->dofs_offset + j * prb_sec->dofs_entsize); if (probe->dofpr_func >= str_sec->dofs_size) { dtrace_dof_error(dof, "invalid function name"); return (-1); } if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) { dtrace_dof_error(dof, "function name too long"); return (-1); } if (probe->dofpr_name >= str_sec->dofs_size || strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) { dtrace_dof_error(dof, "invalid probe name"); return (-1); } /* * The offset count must not wrap the index, and the offsets * must also not overflow the section's data. */ if (probe->dofpr_offidx + probe->dofpr_noffs < probe->dofpr_offidx || (probe->dofpr_offidx + probe->dofpr_noffs) * off_sec->dofs_entsize > off_sec->dofs_size) { dtrace_dof_error(dof, "invalid probe offset"); return (-1); } if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) { /* * If there's no is-enabled offset section, make sure * there aren't any is-enabled offsets. Otherwise * perform the same checks as for probe offsets * (immediately above). */ if (enoff_sec == NULL) { if (probe->dofpr_enoffidx != 0 || probe->dofpr_nenoffs != 0) { dtrace_dof_error(dof, "is-enabled " "offsets with null section"); return (-1); } } else if (probe->dofpr_enoffidx + probe->dofpr_nenoffs < probe->dofpr_enoffidx || (probe->dofpr_enoffidx + probe->dofpr_nenoffs) * enoff_sec->dofs_entsize > enoff_sec->dofs_size) { dtrace_dof_error(dof, "invalid is-enabled " "offset"); return (-1); } if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) { dtrace_dof_error(dof, "zero probe and " "is-enabled offsets"); return (-1); } } else if (probe->dofpr_noffs == 0) { dtrace_dof_error(dof, "zero probe offsets"); return (-1); } if (probe->dofpr_argidx + probe->dofpr_xargc < probe->dofpr_argidx || (probe->dofpr_argidx + probe->dofpr_xargc) * arg_sec->dofs_entsize > arg_sec->dofs_size) { dtrace_dof_error(dof, "invalid args"); return (-1); } typeidx = probe->dofpr_nargv; typestr = strtab + probe->dofpr_nargv; for (k = 0; k < probe->dofpr_nargc; k++) { if (typeidx >= str_sec->dofs_size) { dtrace_dof_error(dof, "bad " "native argument type"); return (-1); } typesz = strlen(typestr) + 1; if (typesz > DTRACE_ARGTYPELEN) { dtrace_dof_error(dof, "native " "argument type too long"); return (-1); } typeidx += typesz; typestr += typesz; } typeidx = probe->dofpr_xargv; typestr = strtab + probe->dofpr_xargv; for (k = 0; k < probe->dofpr_xargc; k++) { if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) { dtrace_dof_error(dof, "bad " "native argument index"); return (-1); } if (typeidx >= str_sec->dofs_size) { dtrace_dof_error(dof, "bad " "translated argument type"); return (-1); } typesz = strlen(typestr) + 1; if (typesz > DTRACE_ARGTYPELEN) { dtrace_dof_error(dof, "translated argument " "type too long"); return (-1); } typeidx += typesz; typestr += typesz; } } return (0); } static int dtrace_helper_slurp(proc_t* p, dof_hdr_t *dof, dof_helper_t *dhp) { dtrace_helpers_t *help; dtrace_vstate_t *vstate; dtrace_enabling_t *enab = NULL; int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1; uintptr_t daddr = (uintptr_t)dof; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); if ((help = p->p_dtrace_helpers) == NULL) help = dtrace_helpers_create(p); vstate = &help->dthps_vstate; if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab, dhp != NULL ? dhp->dofhp_addr : 0, B_FALSE)) != 0) { dtrace_dof_destroy(dof); return (rv); } /* * Look for helper providers and validate their descriptions. */ if (dhp != NULL) { for (i = 0; (uint32_t)i < dof->dofh_secnum; i++) { dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff + i * dof->dofh_secsize); if (sec->dofs_type != DOF_SECT_PROVIDER) continue; if (dtrace_helper_provider_validate(dof, sec) != 0) { dtrace_enabling_destroy(enab); dtrace_dof_destroy(dof); return (-1); } nprovs++; } } /* * Now we need to walk through the ECB descriptions in the enabling. */ for (i = 0; i < enab->dten_ndesc; i++) { dtrace_ecbdesc_t *ep = enab->dten_desc[i]; dtrace_probedesc_t *desc = &ep->dted_probe; /* APPLE NOTE: Darwin employs size bounded string operation. */ if (!LIT_STRNEQL(desc->dtpd_provider, "dtrace")) continue; if (!LIT_STRNEQL(desc->dtpd_mod, "helper")) continue; if (!LIT_STRNEQL(desc->dtpd_func, "ustack")) continue; if ((rv = dtrace_helper_action_add(p, DTRACE_HELPER_ACTION_USTACK, ep)) != 0) { /* * Adding this helper action failed -- we are now going * to rip out the entire generation and return failure. */ (void) dtrace_helper_destroygen(p, help->dthps_generation); dtrace_enabling_destroy(enab); dtrace_dof_destroy(dof); return (-1); } nhelpers++; } if (nhelpers < enab->dten_ndesc) dtrace_dof_error(dof, "unmatched helpers"); gen = help->dthps_generation++; dtrace_enabling_destroy(enab); if (dhp != NULL && nprovs > 0) { dhp->dofhp_dof = (uint64_t)(uintptr_t)dof; if (dtrace_helper_provider_add(p, dhp, gen) == 0) { lck_mtx_unlock(&dtrace_lock); dtrace_helper_provider_register(p, help, dhp); lck_mtx_lock(&dtrace_lock); destroy = 0; } } if (destroy) dtrace_dof_destroy(dof); return (gen); } /* * APPLE NOTE: DTrace lazy dof implementation * * DTrace user static probes (USDT probes) and helper actions are loaded * in a process by proccessing dof sections. The dof sections are passed * into the kernel by dyld, in a dof_ioctl_data_t block. It is rather * expensive to process dof for a process that will never use it. There * is a memory cost (allocating the providers/probes), and a cpu cost * (creating the providers/probes). * * To reduce this cost, we use "lazy dof". The normal proceedure for * dof processing is to copyin the dof(s) pointed to by the dof_ioctl_data_t * block, and invoke dof_slurp_helper() on them. When "lazy dof" is * used, each process retains the dof_ioctl_data_t block, instead of * copying in the data it points to. * * The dof_ioctl_data_t blocks are managed as if they were the actual * processed dof; on fork the block is copied to the child, on exec and * exit the block is freed. * * If the process loads library(s) containing additional dof, the * new dof_ioctl_data_t is merged with the existing block. * * There are a few catches that make this slightly more difficult. * When dyld registers dof_ioctl_data_t blocks, it expects a unique * identifier value for each dof in the block. In non-lazy dof terms, * this is the generation that dof was loaded in. If we hand back * a UID for a lazy dof, that same UID must be able to unload the * dof once it has become non-lazy. To meet this requirement, the * code that loads lazy dof requires that the UID's for dof(s) in * the lazy dof be sorted, and in ascending order. It is okay to skip * UID's, I.E., 1 -> 5 -> 6 is legal. * * Once a process has become non-lazy, it will stay non-lazy. All * future dof operations for that process will be non-lazy, even * if the dof mode transitions back to lazy. * * Always do lazy dof checks before non-lazy (I.E. In fork, exit, exec.). * That way if the lazy check fails due to transitioning to non-lazy, the * right thing is done with the newly faulted in dof. */ /* * This method is a bit squicky. It must handle: * * dof should not be lazy. * dof should have been handled lazily, but there was an error * dof was handled lazily, and needs to be freed. * dof was handled lazily, and must not be freed. * * * Returns EACCESS if dof should be handled non-lazily. * * KERN_SUCCESS and all other return codes indicate lazy handling of dof. * * If the dofs data is claimed by this method, dofs_claimed will be set. * Callers should not free claimed dofs. */ static int dtrace_lazy_dofs_add(proc_t *p, dof_ioctl_data_t* incoming_dofs, int *dofs_claimed) { ASSERT(p); ASSERT(incoming_dofs && incoming_dofs->dofiod_count > 0); int rval = 0; *dofs_claimed = 0; lck_rw_lock_shared(&dtrace_dof_mode_lock); /* * If we have lazy dof, dof mode better be LAZY_ON. */ ASSERT(p->p_dtrace_lazy_dofs == NULL || dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON); ASSERT(p->p_dtrace_lazy_dofs == NULL || p->p_dtrace_helpers == NULL); ASSERT(dtrace_dof_mode != DTRACE_DOF_MODE_NEVER); /* * Any existing helpers force non-lazy behavior. */ if (dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON && (p->p_dtrace_helpers == NULL)) { lck_mtx_lock(&p->p_dtrace_sprlock); dof_ioctl_data_t* existing_dofs = p->p_dtrace_lazy_dofs; unsigned int existing_dofs_count = (existing_dofs) ? existing_dofs->dofiod_count : 0; unsigned int i, merged_dofs_count = incoming_dofs->dofiod_count + existing_dofs_count; /* * Range check... */ if (merged_dofs_count == 0 || merged_dofs_count > 1024) { dtrace_dof_error(NULL, "lazy_dofs_add merged_dofs_count out of range"); rval = EINVAL; goto unlock; } /* * Each dof being added must be assigned a unique generation. */ uint64_t generation = (existing_dofs) ? existing_dofs->dofiod_helpers[existing_dofs_count - 1].dofhp_dof + 1 : 1; for (i=0; idofiod_count; i++) { /* * We rely on these being the same so we can overwrite dofhp_dof and not lose info. */ ASSERT(incoming_dofs->dofiod_helpers[i].dofhp_dof == incoming_dofs->dofiod_helpers[i].dofhp_addr); incoming_dofs->dofiod_helpers[i].dofhp_dof = generation++; } if (existing_dofs) { /* * Merge the existing and incoming dofs */ size_t merged_dofs_size = DOF_IOCTL_DATA_T_SIZE(merged_dofs_count); dof_ioctl_data_t* merged_dofs = kmem_alloc(merged_dofs_size, KM_SLEEP); bcopy(&existing_dofs->dofiod_helpers[0], &merged_dofs->dofiod_helpers[0], sizeof(dof_helper_t) * existing_dofs_count); bcopy(&incoming_dofs->dofiod_helpers[0], &merged_dofs->dofiod_helpers[existing_dofs_count], sizeof(dof_helper_t) * incoming_dofs->dofiod_count); merged_dofs->dofiod_count = merged_dofs_count; kmem_free(existing_dofs, DOF_IOCTL_DATA_T_SIZE(existing_dofs_count)); p->p_dtrace_lazy_dofs = merged_dofs; } else { /* * Claim the incoming dofs */ *dofs_claimed = 1; p->p_dtrace_lazy_dofs = incoming_dofs; } #if DEBUG dof_ioctl_data_t* all_dofs = p->p_dtrace_lazy_dofs; for (i=0; idofiod_count-1; i++) { ASSERT(all_dofs->dofiod_helpers[i].dofhp_dof < all_dofs->dofiod_helpers[i+1].dofhp_dof); } #endif /* DEBUG */ unlock: lck_mtx_unlock(&p->p_dtrace_sprlock); } else { rval = EACCES; } lck_rw_unlock_shared(&dtrace_dof_mode_lock); return rval; } /* * Returns: * * EINVAL: lazy dof is enabled, but the requested generation was not found. * EACCES: This removal needs to be handled non-lazily. */ static int dtrace_lazy_dofs_remove(proc_t *p, int generation) { int rval = EINVAL; lck_rw_lock_shared(&dtrace_dof_mode_lock); /* * If we have lazy dof, dof mode better be LAZY_ON. */ ASSERT(p->p_dtrace_lazy_dofs == NULL || dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON); ASSERT(p->p_dtrace_lazy_dofs == NULL || p->p_dtrace_helpers == NULL); ASSERT(dtrace_dof_mode != DTRACE_DOF_MODE_NEVER); /* * Any existing helpers force non-lazy behavior. */ if (dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON && (p->p_dtrace_helpers == NULL)) { lck_mtx_lock(&p->p_dtrace_sprlock); dof_ioctl_data_t* existing_dofs = p->p_dtrace_lazy_dofs; if (existing_dofs) { int index, existing_dofs_count = existing_dofs->dofiod_count; for (index=0; indexdofiod_helpers[index].dofhp_dof == generation) { dof_ioctl_data_t* removed_dofs = NULL; /* * If there is only 1 dof, we'll delete it and swap in NULL. */ if (existing_dofs_count > 1) { int removed_dofs_count = existing_dofs_count - 1; size_t removed_dofs_size = DOF_IOCTL_DATA_T_SIZE(removed_dofs_count); removed_dofs = kmem_alloc(removed_dofs_size, KM_SLEEP); removed_dofs->dofiod_count = removed_dofs_count; /* * copy the remaining data. */ if (index > 0) { bcopy(&existing_dofs->dofiod_helpers[0], &removed_dofs->dofiod_helpers[0], index * sizeof(dof_helper_t)); } if (index < existing_dofs_count-1) { bcopy(&existing_dofs->dofiod_helpers[index+1], &removed_dofs->dofiod_helpers[index], (existing_dofs_count - index - 1) * sizeof(dof_helper_t)); } } kmem_free(existing_dofs, DOF_IOCTL_DATA_T_SIZE(existing_dofs_count)); p->p_dtrace_lazy_dofs = removed_dofs; rval = KERN_SUCCESS; break; } } #if DEBUG dof_ioctl_data_t* all_dofs = p->p_dtrace_lazy_dofs; if (all_dofs) { unsigned int i; for (i=0; idofiod_count-1; i++) { ASSERT(all_dofs->dofiod_helpers[i].dofhp_dof < all_dofs->dofiod_helpers[i+1].dofhp_dof); } } #endif } lck_mtx_unlock(&p->p_dtrace_sprlock); } else { rval = EACCES; } lck_rw_unlock_shared(&dtrace_dof_mode_lock); return rval; } void dtrace_lazy_dofs_destroy(proc_t *p) { lck_rw_lock_shared(&dtrace_dof_mode_lock); lck_mtx_lock(&p->p_dtrace_sprlock); /* * If we have lazy dof, dof mode better be LAZY_ON, or we must be exiting. * We cannot assert against DTRACE_DOF_MODE_NEVER here, because we are called from * kern_exit.c and kern_exec.c. */ ASSERT(p->p_dtrace_lazy_dofs == NULL || dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON || p->p_lflag & P_LEXIT); ASSERT(p->p_dtrace_lazy_dofs == NULL || p->p_dtrace_helpers == NULL); dof_ioctl_data_t* lazy_dofs = p->p_dtrace_lazy_dofs; p->p_dtrace_lazy_dofs = NULL; lck_mtx_unlock(&p->p_dtrace_sprlock); lck_rw_unlock_shared(&dtrace_dof_mode_lock); if (lazy_dofs) { kmem_free(lazy_dofs, DOF_IOCTL_DATA_T_SIZE(lazy_dofs->dofiod_count)); } } void dtrace_lazy_dofs_duplicate(proc_t *parent, proc_t *child) { lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_NOTOWNED); lck_mtx_assert(&parent->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED); lck_mtx_assert(&child->p_dtrace_sprlock, LCK_MTX_ASSERT_NOTOWNED); lck_rw_lock_shared(&dtrace_dof_mode_lock); lck_mtx_lock(&parent->p_dtrace_sprlock); /* * If we have lazy dof, dof mode better be LAZY_ON, or we must be exiting. * We cannot assert against DTRACE_DOF_MODE_NEVER here, because we are called from * kern_fork.c */ ASSERT(parent->p_dtrace_lazy_dofs == NULL || dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON); ASSERT(parent->p_dtrace_lazy_dofs == NULL || parent->p_dtrace_helpers == NULL); /* * In theory we should hold the child sprlock, but this is safe... */ ASSERT(child->p_dtrace_lazy_dofs == NULL && child->p_dtrace_helpers == NULL); dof_ioctl_data_t* parent_dofs = parent->p_dtrace_lazy_dofs; dof_ioctl_data_t* child_dofs = NULL; if (parent_dofs) { size_t parent_dofs_size = DOF_IOCTL_DATA_T_SIZE(parent_dofs->dofiod_count); child_dofs = kmem_alloc(parent_dofs_size, KM_SLEEP); bcopy(parent_dofs, child_dofs, parent_dofs_size); } lck_mtx_unlock(&parent->p_dtrace_sprlock); if (child_dofs) { lck_mtx_lock(&child->p_dtrace_sprlock); child->p_dtrace_lazy_dofs = child_dofs; lck_mtx_unlock(&child->p_dtrace_sprlock); } lck_rw_unlock_shared(&dtrace_dof_mode_lock); } static int dtrace_lazy_dofs_proc_iterate_filter(proc_t *p, void* ignored) { #pragma unused(ignored) /* * Okay to NULL test without taking the sprlock. */ return p->p_dtrace_lazy_dofs != NULL; } static int dtrace_lazy_dofs_proc_iterate_doit(proc_t *p, void* ignored) { #pragma unused(ignored) /* * It is possible this process may exit during our attempt to * fault in the dof. We could fix this by holding locks longer, * but the errors are benign. */ lck_mtx_lock(&p->p_dtrace_sprlock); /* * In this case only, it is okay to have lazy dof when dof mode is DTRACE_DOF_MODE_LAZY_OFF */ ASSERT(p->p_dtrace_lazy_dofs == NULL || p->p_dtrace_helpers == NULL); ASSERT(dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_OFF); dof_ioctl_data_t* lazy_dofs = p->p_dtrace_lazy_dofs; p->p_dtrace_lazy_dofs = NULL; lck_mtx_unlock(&p->p_dtrace_sprlock); /* * Process each dof_helper_t */ if (lazy_dofs != NULL) { unsigned int i; int rval; for (i=0; idofiod_count; i++) { /* * When loading lazy dof, we depend on the generations being sorted in ascending order. */ ASSERT(i >= (lazy_dofs->dofiod_count - 1) || lazy_dofs->dofiod_helpers[i].dofhp_dof < lazy_dofs->dofiod_helpers[i+1].dofhp_dof); dof_helper_t *dhp = &lazy_dofs->dofiod_helpers[i]; /* * We stored the generation in dofhp_dof. Save it, and restore the original value. */ int generation = dhp->dofhp_dof; dhp->dofhp_dof = dhp->dofhp_addr; dof_hdr_t *dof = dtrace_dof_copyin_from_proc(p, dhp->dofhp_dof, &rval); if (dof != NULL) { dtrace_helpers_t *help; lck_mtx_lock(&dtrace_lock); /* * This must be done with the dtrace_lock held */ if ((help = p->p_dtrace_helpers) == NULL) help = dtrace_helpers_create(p); /* * If the generation value has been bumped, someone snuck in * when we released the dtrace lock. We have to dump this generation, * there is no safe way to load it. */ if (help->dthps_generation <= generation) { help->dthps_generation = generation; /* * dtrace_helper_slurp() takes responsibility for the dof -- * it may free it now or it may save it and free it later. */ if ((rval = dtrace_helper_slurp(p, dof, dhp)) != generation) { dtrace_dof_error(NULL, "returned value did not match expected generation"); } } lck_mtx_unlock(&dtrace_lock); } } kmem_free(lazy_dofs, DOF_IOCTL_DATA_T_SIZE(lazy_dofs->dofiod_count)); } return PROC_RETURNED; } static dtrace_helpers_t * dtrace_helpers_create(proc_t *p) { dtrace_helpers_t *help; lck_mtx_assert(&dtrace_lock, LCK_MTX_ASSERT_OWNED); ASSERT(p->p_dtrace_helpers == NULL); help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP); help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS, KM_SLEEP); p->p_dtrace_helpers = help; dtrace_helpers++; return (help); } static void dtrace_helpers_destroy(proc_t* p) { dtrace_helpers_t *help; dtrace_vstate_t *vstate; uint_t i; lck_mtx_lock(&dtrace_lock); ASSERT(p->p_dtrace_helpers != NULL); ASSERT(dtrace_helpers > 0); help = p->p_dtrace_helpers; vstate = &help->dthps_vstate; /* * We're now going to lose the help from this process. */ p->p_dtrace_helpers = NULL; dtrace_sync(); /* * Destory the helper actions. */ for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { dtrace_helper_action_t *h, *next; for (h = help->dthps_actions[i]; h != NULL; h = next) { next = h->dtha_next; dtrace_helper_action_destroy(h, vstate); h = next; } } lck_mtx_unlock(&dtrace_lock); /* * Destroy the helper providers. */ if (help->dthps_maxprovs > 0) { lck_mtx_lock(&dtrace_meta_lock); if (dtrace_meta_pid != NULL) { ASSERT(dtrace_deferred_pid == NULL); for (i = 0; i < help->dthps_nprovs; i++) { dtrace_helper_provider_remove( &help->dthps_provs[i]->dthp_prov, p->p_pid); } } else { lck_mtx_lock(&dtrace_lock); ASSERT(help->dthps_deferred == 0 || help->dthps_next != NULL || help->dthps_prev != NULL || help == dtrace_deferred_pid); /* * Remove the helper from the deferred list. */ if (help->dthps_next != NULL) help->dthps_next->dthps_prev = help->dthps_prev; if (help->dthps_prev != NULL) help->dthps_prev->dthps_next = help->dthps_next; if (dtrace_deferred_pid == help) { dtrace_deferred_pid = help->dthps_next; ASSERT(help->dthps_prev == NULL); } lck_mtx_unlock(&dtrace_lock); } lck_mtx_unlock(&dtrace_meta_lock); for (i = 0; i < help->dthps_nprovs; i++) { dtrace_helper_provider_destroy(help->dthps_provs[i]); } kmem_free(help->dthps_provs, help->dthps_maxprovs * sizeof (dtrace_helper_provider_t *)); } lck_mtx_lock(&dtrace_lock); dtrace_vstate_fini(&help->dthps_vstate); kmem_free(help->dthps_actions, sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS); kmem_free(help, sizeof (dtrace_helpers_t)); --dtrace_helpers; lck_mtx_unlock(&dtrace_lock); } static void dtrace_helpers_duplicate(proc_t *from, proc_t *to) { dtrace_helpers_t *help, *newhelp; dtrace_helper_action_t *helper, *new, *last; dtrace_difo_t *dp; dtrace_vstate_t *vstate; uint_t i; int j, sz, hasprovs = 0; lck_mtx_lock(&dtrace_lock); ASSERT(from->p_dtrace_helpers != NULL); ASSERT(dtrace_helpers > 0); help = from->p_dtrace_helpers; newhelp = dtrace_helpers_create(to); ASSERT(to->p_dtrace_helpers != NULL); newhelp->dthps_generation = help->dthps_generation; vstate = &newhelp->dthps_vstate; /* * Duplicate the helper actions. */ for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) { if ((helper = help->dthps_actions[i]) == NULL) continue; for (last = NULL; helper != NULL; helper = helper->dtha_next) { new = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP); new->dtha_generation = helper->dtha_generation; if ((dp = helper->dtha_predicate) != NULL) { dp = dtrace_difo_duplicate(dp, vstate); new->dtha_predicate = dp; } new->dtha_nactions = helper->dtha_nactions; sz = sizeof (dtrace_difo_t *) * new->dtha_nactions; new->dtha_actions = kmem_alloc(sz, KM_SLEEP); for (j = 0; j < new->dtha_nactions; j++) { dtrace_difo_t *dpj = helper->dtha_actions[j]; ASSERT(dpj != NULL); dpj = dtrace_difo_duplicate(dpj, vstate); new->dtha_actions[j] = dpj; } if (last != NULL) { last->dtha_next = new; } else { newhelp->dthps_actions[i] = new; } last = new; } } /* * Duplicate the helper providers and register them with the * DTrace framework. */ if (help->dthps_nprovs > 0) { newhelp->dthps_nprovs = help->dthps_nprovs; newhelp->dthps_maxprovs = help->dthps_nprovs; newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs * sizeof (dtrace_helper_provider_t *), KM_SLEEP); for (i = 0; i < newhelp->dthps_nprovs; i++) { newhelp->dthps_provs[i] = help->dthps_provs[i]; newhelp->dthps_provs[i]->dthp_ref++; } hasprovs = 1; } lck_mtx_unlock(&dtrace_lock); if (hasprovs) dtrace_helper_provider_register(to, newhelp, NULL); } /* * DTrace Hook Functions */ /* * APPLE NOTE: dtrace_modctl_* routines for kext support. * Used to manipulate the modctl list within dtrace xnu. */ modctl_t *dtrace_modctl_list; static void dtrace_modctl_add(struct modctl * newctl) { struct modctl *nextp, *prevp; ASSERT(newctl != NULL); lck_mtx_assert(&mod_lock, LCK_MTX_ASSERT_OWNED); // Insert new module at the front of the list, newctl->mod_next = dtrace_modctl_list; dtrace_modctl_list = newctl; /* * If a module exists with the same name, then that module * must have been unloaded with enabled probes. We will move * the unloaded module to the new module's stale chain and * then stop traversing the list. */ prevp = newctl; nextp = newctl->mod_next; while (nextp != NULL) { if (nextp->mod_loaded) { /* This is a loaded module. Keep traversing. */ prevp = nextp; nextp = nextp->mod_next; continue; } else { /* Found an unloaded module */ if (strncmp (newctl->mod_modname, nextp->mod_modname, KMOD_MAX_NAME)) { /* Names don't match. Keep traversing. */ prevp = nextp; nextp = nextp->mod_next; continue; } else { /* We found a stale entry, move it. We're done. */ prevp->mod_next = nextp->mod_next; newctl->mod_stale = nextp; nextp->mod_next = NULL; break; } } } } static modctl_t * dtrace_modctl_lookup(struct kmod_info * kmod) { lck_mtx_assert(&mod_lock, LCK_MTX_ASSERT_OWNED); struct modctl * ctl; for (ctl = dtrace_modctl_list; ctl; ctl=ctl->mod_next) { if (ctl->mod_id == kmod->id) return(ctl); } return (NULL); } /* * This routine is called from dtrace_module_unloaded(). * It removes a modctl structure and its stale chain * from the kext shadow list. */ static void dtrace_modctl_remove(struct modctl * ctl) { ASSERT(ctl != NULL); lck_mtx_assert(&mod_lock, LCK_MTX_ASSERT_OWNED); modctl_t *prevp, *nextp, *curp; // Remove stale chain first for (curp=ctl->mod_stale; curp != NULL; curp=nextp) { nextp = curp->mod_stale; /* There should NEVER be user symbols allocated at this point */ ASSERT(curp->mod_user_symbols == NULL); kmem_free(curp, sizeof(modctl_t)); } prevp = NULL; curp = dtrace_modctl_list; while (curp != ctl) { prevp = curp; curp = curp->mod_next; } if (prevp != NULL) { prevp->mod_next = ctl->mod_next; } else { dtrace_modctl_list = ctl->mod_next; } /* There should NEVER be user symbols allocated at this point */ ASSERT(ctl->mod_user_symbols == NULL); kmem_free (ctl, sizeof(modctl_t)); } /* * APPLE NOTE: The kext loader will call dtrace_module_loaded * when the kext is loaded in memory, but before calling the * kext's start routine. * * Return 0 on success * Return -1 on failure */ static int dtrace_module_loaded(struct kmod_info *kmod, uint32_t flag) { dtrace_provider_t *prv; /* * If kernel symbols have been disabled, return immediately * DTRACE_KERNEL_SYMBOLS_NEVER is a permanent mode, it is safe to test without holding locks */ if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_NEVER) return 0; struct modctl *ctl = NULL; if (!kmod || kmod->address == 0 || kmod->size == 0) return(-1); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&mod_lock); /* * Have we seen this kext before? */ ctl = dtrace_modctl_lookup(kmod); if (ctl != NULL) { /* bail... we already have this kext in the modctl list */ lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); if (dtrace_err_verbose) cmn_err(CE_WARN, "dtrace load module already exists '%s %u' is failing against '%s %u'", kmod->name, (uint_t)kmod->id, ctl->mod_modname, ctl->mod_id); return(-1); } else { ctl = kmem_alloc(sizeof(struct modctl), KM_SLEEP); if (ctl == NULL) { if (dtrace_err_verbose) cmn_err(CE_WARN, "dtrace module load '%s %u' is failing ", kmod->name, (uint_t)kmod->id); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return (-1); } ctl->mod_next = NULL; ctl->mod_stale = NULL; strlcpy (ctl->mod_modname, kmod->name, sizeof(ctl->mod_modname)); ctl->mod_loadcnt = kmod->id; ctl->mod_nenabled = 0; ctl->mod_address = kmod->address; ctl->mod_size = kmod->size; ctl->mod_id = kmod->id; ctl->mod_loaded = 1; ctl->mod_flags = 0; ctl->mod_user_symbols = NULL; /* * Find the UUID for this module, if it has one */ kernel_mach_header_t* header = (kernel_mach_header_t *)ctl->mod_address; struct load_command* load_cmd = (struct load_command *)&header[1]; uint32_t i; for (i = 0; i < header->ncmds; i++) { if (load_cmd->cmd == LC_UUID) { struct uuid_command* uuid_cmd = (struct uuid_command *)load_cmd; memcpy(ctl->mod_uuid, uuid_cmd->uuid, sizeof(uuid_cmd->uuid)); ctl->mod_flags |= MODCTL_HAS_UUID; break; } load_cmd = (struct load_command *)((caddr_t)load_cmd + load_cmd->cmdsize); } if (ctl->mod_address == g_kernel_kmod_info.address) { ctl->mod_flags |= MODCTL_IS_MACH_KERNEL; } } dtrace_modctl_add(ctl); /* * We must hold the dtrace_lock to safely test non permanent dtrace_fbt_symbol_mode(s) */ lck_mtx_lock(&dtrace_lock); /* * DTrace must decide if it will instrument modules lazily via * userspace symbols (default mode), or instrument immediately via * kernel symbols (non-default mode) * * When in default/lazy mode, DTrace will only support modules * built with a valid UUID. * * Overriding the default can be done explicitly in one of * the following two ways. * * A module can force symbols from kernel space using the plist key, * OSBundleForceDTraceInit (see kmod.h). If this per kext state is set, * we fall through and instrument this module now. * * Or, the boot-arg, dtrace_kernel_symbol_mode, can be set to force symbols * from kernel space (see dtrace_impl.h). If this system state is set * to a non-userspace mode, we fall through and instrument the module now. */ if ((dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_FROM_USERSPACE) && (!(flag & KMOD_DTRACE_FORCE_INIT))) { /* We will instrument the module lazily -- this is the default */ lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return 0; } /* We will instrument the module immediately using kernel symbols */ ctl->mod_flags |= MODCTL_HAS_KERNEL_SYMBOLS; lck_mtx_unlock(&dtrace_lock); /* * We're going to call each providers per-module provide operation * specifying only this module. */ for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next) prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl); /* * APPLE NOTE: The contract with the kext loader is that once this function * has completed, it may delete kernel symbols at will. * We must set this while still holding the mod_lock. */ ctl->mod_flags &= ~MODCTL_HAS_KERNEL_SYMBOLS; lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); /* * If we have any retained enablings, we need to match against them. * Enabling probes requires that cpu_lock be held, and we cannot hold * cpu_lock here -- it is legal for cpu_lock to be held when loading a * module. (In particular, this happens when loading scheduling * classes.) So if we have any retained enablings, we need to dispatch * our task queue to do the match for us. */ lck_mtx_lock(&dtrace_lock); if (dtrace_retained == NULL) { lck_mtx_unlock(&dtrace_lock); return 0; } /* APPLE NOTE! * * The cpu_lock mentioned above is only held by dtrace code, Apple's xnu never actually * holds it for any reason. Thus the comment above is invalid, we can directly invoke * dtrace_enabling_matchall without jumping through all the hoops, and we can avoid * the delay call as well. */ lck_mtx_unlock(&dtrace_lock); dtrace_enabling_matchall(); return 0; } /* * Return 0 on success * Return -1 on failure */ static int dtrace_module_unloaded(struct kmod_info *kmod) { dtrace_probe_t template, *probe, *first, *next; dtrace_provider_t *prov; struct modctl *ctl = NULL; struct modctl *syncctl = NULL; struct modctl *nextsyncctl = NULL; int syncmode = 0; lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&mod_lock); lck_mtx_lock(&dtrace_lock); if (kmod == NULL) { syncmode = 1; } else { ctl = dtrace_modctl_lookup(kmod); if (ctl == NULL) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return (-1); } ctl->mod_loaded = 0; ctl->mod_address = 0; ctl->mod_size = 0; } if (dtrace_bymod == NULL) { /* * The DTrace module is loaded (obviously) but not attached; * we don't have any work to do. */ if (ctl != NULL) (void)dtrace_modctl_remove(ctl); lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return(0); } /* Syncmode set means we target and traverse entire modctl list. */ if (syncmode) nextsyncctl = dtrace_modctl_list; syncloop: if (syncmode) { /* find a stale modctl struct */ for (syncctl = nextsyncctl; syncctl != NULL; syncctl=syncctl->mod_next) { if (syncctl->mod_address == 0) break; } if (syncctl==NULL) { /* We have no more work to do */ lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return(0); } else { /* keep track of next syncctl in case this one is removed */ nextsyncctl = syncctl->mod_next; ctl = syncctl; } } template.dtpr_mod = ctl->mod_modname; for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template); probe != NULL; probe = probe->dtpr_nextmod) { if (probe->dtpr_ecb != NULL) { /* * This shouldn't _actually_ be possible -- we're * unloading a module that has an enabled probe in it. * (It's normally up to the provider to make sure that * this can't happen.) However, because dtps_enable() * doesn't have a failure mode, there can be an * enable/unload race. Upshot: we don't want to * assert, but we're not going to disable the * probe, either. */ if (syncmode) { /* We're syncing, let's look at next in list */ goto syncloop; } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); if (dtrace_err_verbose) { cmn_err(CE_WARN, "unloaded module '%s' had " "enabled probes", ctl->mod_modname); } return(-1); } } probe = first; for (first = NULL; probe != NULL; probe = next) { ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe); dtrace_probes[probe->dtpr_id - 1] = NULL; probe->dtpr_provider->dtpv_probe_count--; next = probe->dtpr_nextmod; dtrace_hash_remove(dtrace_bymod, probe); dtrace_hash_remove(dtrace_byfunc, probe); dtrace_hash_remove(dtrace_byname, probe); if (first == NULL) { first = probe; probe->dtpr_nextmod = NULL; } else { probe->dtpr_nextmod = first; first = probe; } } /* * We've removed all of the module's probes from the hash chains and * from the probe array. Now issue a dtrace_sync() to be sure that * everyone has cleared out from any probe array processing. */ dtrace_sync(); for (probe = first; probe != NULL; probe = first) { first = probe->dtpr_nextmod; prov = probe->dtpr_provider; prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id, probe->dtpr_arg); kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1); kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1); kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1); vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1); zfree(dtrace_probe_t_zone, probe); } dtrace_modctl_remove(ctl); if (syncmode) goto syncloop; lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return(0); } void dtrace_suspend(void) { dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend)); } void dtrace_resume(void) { dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume)); } static int dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu) { lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); lck_mtx_lock(&dtrace_lock); switch (what) { case CPU_CONFIG: { dtrace_state_t *state; dtrace_optval_t *opt, rs, c; /* * For now, we only allocate a new buffer for anonymous state. */ if ((state = dtrace_anon.dta_state) == NULL) break; if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) break; opt = state->dts_options; c = opt[DTRACEOPT_CPU]; if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu) break; /* * Regardless of what the actual policy is, we're going to * temporarily set our resize policy to be manual. We're * also going to temporarily set our CPU option to denote * the newly configured CPU. */ rs = opt[DTRACEOPT_BUFRESIZE]; opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL; opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu; (void) dtrace_state_buffers(state); opt[DTRACEOPT_BUFRESIZE] = rs; opt[DTRACEOPT_CPU] = c; break; } case CPU_UNCONFIG: /* * We don't free the buffer in the CPU_UNCONFIG case. (The * buffer will be freed when the consumer exits.) */ break; default: break; } lck_mtx_unlock(&dtrace_lock); return (0); } static void dtrace_cpu_setup_initial(processorid_t cpu) { (void) dtrace_cpu_setup(CPU_CONFIG, cpu); } static void dtrace_toxrange_add(uintptr_t base, uintptr_t limit) { if (dtrace_toxranges >= dtrace_toxranges_max) { int osize, nsize; dtrace_toxrange_t *range; osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t); if (osize == 0) { ASSERT(dtrace_toxrange == NULL); ASSERT(dtrace_toxranges_max == 0); dtrace_toxranges_max = 1; } else { dtrace_toxranges_max <<= 1; } nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t); range = kmem_zalloc(nsize, KM_SLEEP); if (dtrace_toxrange != NULL) { ASSERT(osize != 0); bcopy(dtrace_toxrange, range, osize); kmem_free(dtrace_toxrange, osize); } dtrace_toxrange = range; } ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == 0); ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == 0); dtrace_toxrange[dtrace_toxranges].dtt_base = base; dtrace_toxrange[dtrace_toxranges].dtt_limit = limit; dtrace_toxranges++; } /* * DTrace Driver Cookbook Functions */ /*ARGSUSED*/ static int dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd) { #pragma unused(cmd) /* __APPLE__ */ dtrace_provider_id_t id; dtrace_state_t *state = NULL; dtrace_enabling_t *enab; lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); if (ddi_soft_state_init(&dtrace_softstate, sizeof (dtrace_state_t), 0) != 0) { cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state"); lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); lck_mtx_unlock(&cpu_lock); return (DDI_FAILURE); } /* Darwin uses BSD cloning device driver to automagically obtain minor device number. */ ddi_report_dev(devi); dtrace_devi = devi; dtrace_modload = dtrace_module_loaded; dtrace_modunload = dtrace_module_unloaded; dtrace_cpu_init = dtrace_cpu_setup_initial; dtrace_helpers_cleanup = dtrace_helpers_destroy; dtrace_helpers_fork = dtrace_helpers_duplicate; dtrace_cpustart_init = dtrace_suspend; dtrace_cpustart_fini = dtrace_resume; dtrace_debugger_init = dtrace_suspend; dtrace_debugger_fini = dtrace_resume; register_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1, NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER); dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE, UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER); dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri, 1, INT_MAX, 0); dtrace_state_cache = kmem_cache_create("dtrace_state_cache", sizeof (dtrace_dstate_percpu_t) * (int)NCPU, DTRACE_STATE_ALIGN, NULL, NULL, NULL, NULL, NULL, 0); lck_mtx_assert(&cpu_lock, LCK_MTX_ASSERT_OWNED); dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod), offsetof(dtrace_probe_t, dtpr_nextmod), offsetof(dtrace_probe_t, dtpr_prevmod)); dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func), offsetof(dtrace_probe_t, dtpr_nextfunc), offsetof(dtrace_probe_t, dtpr_prevfunc)); dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name), offsetof(dtrace_probe_t, dtpr_nextname), offsetof(dtrace_probe_t, dtpr_prevname)); if (dtrace_retain_max < 1) { cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; " "setting to 1", dtrace_retain_max); dtrace_retain_max = 1; } /* * Now discover our toxic ranges. */ dtrace_toxic_ranges(dtrace_toxrange_add); /* * Before we register ourselves as a provider to our own framework, * we would like to assert that dtrace_provider is NULL -- but that's * not true if we were loaded as a dependency of a DTrace provider. * Once we've registered, we can assert that dtrace_provider is our * pseudo provider. */ (void) dtrace_register("dtrace", &dtrace_provider_attr, DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id); ASSERT(dtrace_provider != NULL); ASSERT((dtrace_provider_id_t)dtrace_provider == id); #if defined (__x86_64__) dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t) dtrace_provider, NULL, NULL, "BEGIN", 1, NULL); dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t) dtrace_provider, NULL, NULL, "END", 0, NULL); dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t) dtrace_provider, NULL, NULL, "ERROR", 3, NULL); #else #error Unknown Architecture #endif dtrace_anon_property(); lck_mtx_unlock(&cpu_lock); /* * If DTrace helper tracing is enabled, we need to allocate the * trace buffer and initialize the values. */ if (dtrace_helptrace_enabled) { ASSERT(dtrace_helptrace_buffer == NULL); dtrace_helptrace_buffer = kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP); dtrace_helptrace_next = 0; } /* * If there are already providers, we must ask them to provide their * probes, and then match any anonymous enabling against them. Note * that there should be no other retained enablings at this time: * the only retained enablings at this time should be the anonymous * enabling. */ if (dtrace_anon.dta_enabling != NULL) { ASSERT(dtrace_retained == dtrace_anon.dta_enabling); /* * APPLE NOTE: if handling anonymous dof, switch symbol modes. */ if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_FROM_USERSPACE) { dtrace_kernel_symbol_mode = DTRACE_KERNEL_SYMBOLS_FROM_KERNEL; } dtrace_enabling_provide(NULL); state = dtrace_anon.dta_state; /* * We couldn't hold cpu_lock across the above call to * dtrace_enabling_provide(), but we must hold it to actually * enable the probes. We have to drop all of our locks, pick * up cpu_lock, and regain our locks before matching the * retained anonymous enabling. */ lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); if ((enab = dtrace_anon.dta_enabling) != NULL) (void) dtrace_enabling_match(enab, NULL); lck_mtx_unlock(&cpu_lock); } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); if (state != NULL) { /* * If we created any anonymous state, set it going now. */ (void) dtrace_state_go(state, &dtrace_anon.dta_beganon); } return (DDI_SUCCESS); } /*ARGSUSED*/ static int dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p) { #pragma unused(flag, otyp) dtrace_state_t *state; uint32_t priv; uid_t uid; zoneid_t zoneid; int rv; /* APPLE: Darwin puts Helper on its own major device. */ /* * If no DTRACE_PRIV_* bits are set in the credential, then the * caller lacks sufficient permission to do anything with DTrace. */ dtrace_cred2priv(cred_p, &priv, &uid, &zoneid); if (priv == DTRACE_PRIV_NONE) return (EACCES); /* * APPLE NOTE: We delay the initialization of fasttrap as late as possible. * It certainly can't be later than now! */ fasttrap_init(); /* * Ask all providers to provide all their probes. */ lck_mtx_lock(&dtrace_provider_lock); dtrace_probe_provide(NULL, NULL); lck_mtx_unlock(&dtrace_provider_lock); lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_lock); dtrace_opens++; dtrace_membar_producer(); /* * If the kernel debugger is active (that is, if the kernel debugger * modified text in some way), we won't allow the open. */ if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) { dtrace_opens--; lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); return (EBUSY); } rv = dtrace_state_create(devp, cred_p, &state); lck_mtx_unlock(&cpu_lock); if (rv != 0 || state == NULL) { if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL) (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); lck_mtx_unlock(&dtrace_lock); /* propagate EAGAIN or ERESTART */ return (rv); } lck_mtx_unlock(&dtrace_lock); lck_rw_lock_exclusive(&dtrace_dof_mode_lock); /* * If we are currently lazy, transition states. * * Unlike dtrace_close, we do not need to check the * value of dtrace_opens, as any positive value (and * we count as 1) means we transition states. */ if (dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_ON) { dtrace_dof_mode = DTRACE_DOF_MODE_LAZY_OFF; /* * Iterate all existing processes and load lazy dofs. */ proc_iterate(PROC_ALLPROCLIST | PROC_NOWAITTRANS, dtrace_lazy_dofs_proc_iterate_doit, NULL, dtrace_lazy_dofs_proc_iterate_filter, NULL); } lck_rw_unlock_exclusive(&dtrace_dof_mode_lock); /* * Update kernel symbol state. * * We must own the provider and dtrace locks. * * NOTE! It may appear there is a race by setting this value so late * after dtrace_probe_provide. However, any kext loaded after the * call to probe provide and before we set LAZY_OFF will be marked as * eligible for symbols from userspace. The same dtrace that is currently * calling dtrace_open() (this call!) will get a list of kexts needing * symbols and fill them in, thus closing the race window. * * We want to set this value only after it certain it will succeed, as * this significantly reduces the complexity of error exits. */ lck_mtx_lock(&dtrace_lock); if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_FROM_USERSPACE) { dtrace_kernel_symbol_mode = DTRACE_KERNEL_SYMBOLS_FROM_KERNEL; } lck_mtx_unlock(&dtrace_lock); return (0); } /*ARGSUSED*/ static int dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p) { #pragma unused(flag, otyp, cred_p) /* __APPLE__ */ minor_t minor = getminor(dev); dtrace_state_t *state; /* APPLE NOTE: Darwin puts Helper on its own major device. */ state = ddi_get_soft_state(dtrace_softstate, minor); lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_lock); if (state->dts_anon) { /* * There is anonymous state. Destroy that first. */ ASSERT(dtrace_anon.dta_state == NULL); dtrace_state_destroy(state->dts_anon); } dtrace_state_destroy(state); ASSERT(dtrace_opens > 0); /* * Only relinquish control of the kernel debugger interface when there * are no consumers and no anonymous enablings. */ if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL) (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); /* * Lock ordering requires the dof mode lock be taken before * the dtrace_lock. */ lck_rw_lock_exclusive(&dtrace_dof_mode_lock); lck_mtx_lock(&dtrace_lock); if (dtrace_opens == 0) { /* * If we are currently lazy-off, and this is the last close, transition to * lazy state. */ if (dtrace_dof_mode == DTRACE_DOF_MODE_LAZY_OFF) { dtrace_dof_mode = DTRACE_DOF_MODE_LAZY_ON; } /* * If we are the last dtrace client, switch back to lazy (from userspace) symbols */ if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_FROM_KERNEL) { dtrace_kernel_symbol_mode = DTRACE_KERNEL_SYMBOLS_FROM_USERSPACE; } } lck_mtx_unlock(&dtrace_lock); lck_rw_unlock_exclusive(&dtrace_dof_mode_lock); /* * Kext probes may be retained past the end of the kext's lifespan. The * probes are kept until the last reference to them has been removed. * Since closing an active dtrace context is likely to drop that last reference, * lets take a shot at cleaning out the orphaned probes now. */ dtrace_module_unloaded(NULL); return (0); } /*ARGSUSED*/ static int dtrace_ioctl_helper(u_long cmd, caddr_t arg, int *rv) { #pragma unused(rv) /* * Safe to check this outside the dof mode lock */ if (dtrace_dof_mode == DTRACE_DOF_MODE_NEVER) return KERN_SUCCESS; switch (cmd) { case DTRACEHIOC_ADDDOF: { dof_helper_t *dhp = NULL; size_t dof_ioctl_data_size; dof_ioctl_data_t* multi_dof; unsigned int i; int rval = 0; user_addr_t user_address = *(user_addr_t*)arg; uint64_t dof_count; int multi_dof_claimed = 0; proc_t* p = current_proc(); /* * Read the number of DOF sections being passed in. */ if (copyin(user_address + offsetof(dof_ioctl_data_t, dofiod_count), &dof_count, sizeof(dof_count))) { dtrace_dof_error(NULL, "failed to copyin dofiod_count"); return (EFAULT); } /* * Range check the count. */ if (dof_count == 0 || dof_count > 1024) { dtrace_dof_error(NULL, "dofiod_count is not valid"); return (EINVAL); } /* * Allocate a correctly sized structure and copyin the data. */ dof_ioctl_data_size = DOF_IOCTL_DATA_T_SIZE(dof_count); if ((multi_dof = kmem_alloc(dof_ioctl_data_size, KM_SLEEP)) == NULL) return (ENOMEM); /* NOTE! We can no longer exit this method via return */ if (copyin(user_address, multi_dof, dof_ioctl_data_size) != 0) { dtrace_dof_error(NULL, "failed copyin of dof_ioctl_data_t"); rval = EFAULT; goto cleanup; } /* * Check that the count didn't change between the first copyin and the second. */ if (multi_dof->dofiod_count != dof_count) { rval = EINVAL; goto cleanup; } /* * Try to process lazily first. */ rval = dtrace_lazy_dofs_add(p, multi_dof, &multi_dof_claimed); /* * If rval is EACCES, we must be non-lazy. */ if (rval == EACCES) { rval = 0; /* * Process each dof_helper_t */ i = 0; do { dhp = &multi_dof->dofiod_helpers[i]; dof_hdr_t *dof = dtrace_dof_copyin(dhp->dofhp_dof, &rval); if (dof != NULL) { lck_mtx_lock(&dtrace_lock); /* * dtrace_helper_slurp() takes responsibility for the dof -- * it may free it now or it may save it and free it later. */ if ((dhp->dofhp_dof = (uint64_t)dtrace_helper_slurp(p, dof, dhp)) == -1ULL) { rval = EINVAL; } lck_mtx_unlock(&dtrace_lock); } } while (++i < multi_dof->dofiod_count && rval == 0); } /* * We need to copyout the multi_dof struct, because it contains * the generation (unique id) values needed to call DTRACEHIOC_REMOVE * * This could certainly be better optimized. */ if (copyout(multi_dof, user_address, dof_ioctl_data_size) != 0) { dtrace_dof_error(NULL, "failed copyout of dof_ioctl_data_t"); /* Don't overwrite pre-existing error code */ if (rval == 0) rval = EFAULT; } cleanup: /* * If we had to allocate struct memory, free it. */ if (multi_dof != NULL && !multi_dof_claimed) { kmem_free(multi_dof, dof_ioctl_data_size); } return rval; } case DTRACEHIOC_REMOVE: { int generation = *(int*)arg; proc_t* p = current_proc(); /* * Try lazy first. */ int rval = dtrace_lazy_dofs_remove(p, generation); /* * EACCES means non-lazy */ if (rval == EACCES) { lck_mtx_lock(&dtrace_lock); rval = dtrace_helper_destroygen(p, generation); lck_mtx_unlock(&dtrace_lock); } return (rval); } default: break; } return ENOTTY; } /*ARGSUSED*/ static int dtrace_ioctl(dev_t dev, u_long cmd, user_addr_t arg, int md, cred_t *cr, int *rv) { #pragma unused(md) minor_t minor = getminor(dev); dtrace_state_t *state; int rval; /* Darwin puts Helper on its own major device. */ state = ddi_get_soft_state(dtrace_softstate, minor); if (state->dts_anon) { ASSERT(dtrace_anon.dta_state == NULL); state = state->dts_anon; } switch (cmd) { case DTRACEIOC_PROVIDER: { dtrace_providerdesc_t pvd; dtrace_provider_t *pvp; if (copyin(arg, &pvd, sizeof (pvd)) != 0) return (EFAULT); pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0'; lck_mtx_lock(&dtrace_provider_lock); for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) { if (strncmp(pvp->dtpv_name, pvd.dtvd_name, DTRACE_PROVNAMELEN) == 0) break; } lck_mtx_unlock(&dtrace_provider_lock); if (pvp == NULL) return (ESRCH); bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t)); bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t)); if (copyout(&pvd, arg, sizeof (pvd)) != 0) return (EFAULT); return (0); } case DTRACEIOC_EPROBE: { dtrace_eprobedesc_t epdesc; dtrace_ecb_t *ecb; dtrace_action_t *act; void *buf; size_t size; uintptr_t dest; int nrecs; if (copyin(arg, &epdesc, sizeof (epdesc)) != 0) return (EFAULT); lck_mtx_lock(&dtrace_lock); if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } if (ecb->dte_probe == NULL) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id; epdesc.dtepd_uarg = ecb->dte_uarg; epdesc.dtepd_size = ecb->dte_size; nrecs = epdesc.dtepd_nrecs; epdesc.dtepd_nrecs = 0; for (act = ecb->dte_action; act != NULL; act = act->dta_next) { if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple) continue; epdesc.dtepd_nrecs++; } /* * Now that we have the size, we need to allocate a temporary * buffer in which to store the complete description. We need * the temporary buffer to be able to drop dtrace_lock() * across the copyout(), below. */ size = sizeof (dtrace_eprobedesc_t) + (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t)); buf = kmem_alloc(size, KM_SLEEP); dest = (uintptr_t)buf; bcopy(&epdesc, (void *)dest, sizeof (epdesc)); dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]); for (act = ecb->dte_action; act != NULL; act = act->dta_next) { if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple) continue; if (nrecs-- == 0) break; bcopy(&act->dta_rec, (void *)dest, sizeof (dtrace_recdesc_t)); dest += sizeof (dtrace_recdesc_t); } lck_mtx_unlock(&dtrace_lock); if (copyout(buf, arg, dest - (uintptr_t)buf) != 0) { kmem_free(buf, size); return (EFAULT); } kmem_free(buf, size); return (0); } case DTRACEIOC_AGGDESC: { dtrace_aggdesc_t aggdesc; dtrace_action_t *act; dtrace_aggregation_t *agg; int nrecs; uint32_t offs; dtrace_recdesc_t *lrec; void *buf; size_t size; uintptr_t dest; if (copyin(arg, &aggdesc, sizeof (aggdesc)) != 0) return (EFAULT); lck_mtx_lock(&dtrace_lock); if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid; nrecs = aggdesc.dtagd_nrecs; aggdesc.dtagd_nrecs = 0; offs = agg->dtag_base; lrec = &agg->dtag_action.dta_rec; aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs; for (act = agg->dtag_first; ; act = act->dta_next) { ASSERT(act->dta_intuple || DTRACEACT_ISAGG(act->dta_kind)); /* * If this action has a record size of zero, it * denotes an argument to the aggregating action. * Because the presence of this record doesn't (or * shouldn't) affect the way the data is interpreted, * we don't copy it out to save user-level the * confusion of dealing with a zero-length record. */ if (act->dta_rec.dtrd_size == 0) { ASSERT(agg->dtag_hasarg); continue; } aggdesc.dtagd_nrecs++; if (act == &agg->dtag_action) break; } /* * Now that we have the size, we need to allocate a temporary * buffer in which to store the complete description. We need * the temporary buffer to be able to drop dtrace_lock() * across the copyout(), below. */ size = sizeof (dtrace_aggdesc_t) + (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t)); buf = kmem_alloc(size, KM_SLEEP); dest = (uintptr_t)buf; bcopy(&aggdesc, (void *)dest, sizeof (aggdesc)); dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]); for (act = agg->dtag_first; ; act = act->dta_next) { dtrace_recdesc_t rec = act->dta_rec; /* * See the comment in the above loop for why we pass * over zero-length records. */ if (rec.dtrd_size == 0) { ASSERT(agg->dtag_hasarg); continue; } if (nrecs-- == 0) break; rec.dtrd_offset -= offs; bcopy(&rec, (void *)dest, sizeof (rec)); dest += sizeof (dtrace_recdesc_t); if (act == &agg->dtag_action) break; } lck_mtx_unlock(&dtrace_lock); if (copyout(buf, arg, dest - (uintptr_t)buf) != 0) { kmem_free(buf, size); return (EFAULT); } kmem_free(buf, size); return (0); } case DTRACEIOC_ENABLE: { dof_hdr_t *dof; dtrace_enabling_t *enab = NULL; dtrace_vstate_t *vstate; int err = 0; *rv = 0; /* * If a NULL argument has been passed, we take this as our * cue to reevaluate our enablings. */ if (arg == 0) { dtrace_enabling_matchall(); return (0); } if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL) return (rval); lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_lock); vstate = &state->dts_vstate; if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); dtrace_dof_destroy(dof); return (EBUSY); } if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); dtrace_dof_destroy(dof); return (EINVAL); } if ((rval = dtrace_dof_options(dof, state)) != 0) { dtrace_enabling_destroy(enab); lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); dtrace_dof_destroy(dof); return (rval); } if ((err = dtrace_enabling_match(enab, rv)) == 0) { err = dtrace_enabling_retain(enab); } else { dtrace_enabling_destroy(enab); } lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&cpu_lock); dtrace_dof_destroy(dof); return (err); } case DTRACEIOC_REPLICATE: { dtrace_repldesc_t desc; dtrace_probedesc_t *match = &desc.dtrpd_match; dtrace_probedesc_t *create = &desc.dtrpd_create; int err; if (copyin(arg, &desc, sizeof (desc)) != 0) return (EFAULT); match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; match->dtpd_name[DTRACE_NAMELEN - 1] = '\0'; create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; create->dtpd_name[DTRACE_NAMELEN - 1] = '\0'; lck_mtx_lock(&dtrace_lock); err = dtrace_enabling_replicate(state, match, create); lck_mtx_unlock(&dtrace_lock); return (err); } case DTRACEIOC_PROBEMATCH: case DTRACEIOC_PROBES: { dtrace_probe_t *probe = NULL; dtrace_probedesc_t desc; dtrace_probekey_t pkey; dtrace_id_t i; int m = 0; uint32_t priv; uid_t uid; zoneid_t zoneid; if (copyin(arg, &desc, sizeof (desc)) != 0) return (EFAULT); desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0'; desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0'; desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0'; desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0'; /* * Before we attempt to match this probe, we want to give * all providers the opportunity to provide it. */ if (desc.dtpd_id == DTRACE_IDNONE) { lck_mtx_lock(&dtrace_provider_lock); dtrace_probe_provide(&desc, NULL); lck_mtx_unlock(&dtrace_provider_lock); desc.dtpd_id++; } if (cmd == DTRACEIOC_PROBEMATCH) { dtrace_probekey(&desc, &pkey); pkey.dtpk_id = DTRACE_IDNONE; } dtrace_cred2priv(cr, &priv, &uid, &zoneid); lck_mtx_lock(&dtrace_lock); if (cmd == DTRACEIOC_PROBEMATCH) { /* Quiet compiler warning */ for (i = desc.dtpd_id; i <= (dtrace_id_t)dtrace_nprobes; i++) { if ((probe = dtrace_probes[i - 1]) != NULL && (m = dtrace_match_probe(probe, &pkey, priv, uid, zoneid)) != 0) break; } if (m < 0) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } } else { /* Quiet compiler warning */ for (i = desc.dtpd_id; i <= (dtrace_id_t)dtrace_nprobes; i++) { if ((probe = dtrace_probes[i - 1]) != NULL && dtrace_match_priv(probe, priv, uid, zoneid)) break; } } if (probe == NULL) { lck_mtx_unlock(&dtrace_lock); return (ESRCH); } dtrace_probe_description(probe, &desc); lck_mtx_unlock(&dtrace_lock); if (copyout(&desc, arg, sizeof (desc)) != 0) return (EFAULT); return (0); } case DTRACEIOC_PROBEARG: { dtrace_argdesc_t desc; dtrace_probe_t *probe; dtrace_provider_t *prov; if (copyin(arg, &desc, sizeof (desc)) != 0) return (EFAULT); if (desc.dtargd_id == DTRACE_IDNONE) return (EINVAL); if (desc.dtargd_ndx == DTRACE_ARGNONE) return (EINVAL); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&mod_lock); lck_mtx_lock(&dtrace_lock); /* Quiet compiler warning */ if (desc.dtargd_id > (dtrace_id_t)dtrace_nprobes) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return (EINVAL); } if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); return (EINVAL); } lck_mtx_unlock(&dtrace_lock); prov = probe->dtpr_provider; if (prov->dtpv_pops.dtps_getargdesc == NULL) { /* * There isn't any typed information for this probe. * Set the argument number to DTRACE_ARGNONE. */ desc.dtargd_ndx = DTRACE_ARGNONE; } else { desc.dtargd_native[0] = '\0'; desc.dtargd_xlate[0] = '\0'; desc.dtargd_mapping = desc.dtargd_ndx; prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg, probe->dtpr_id, probe->dtpr_arg, &desc); } lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); if (copyout(&desc, arg, sizeof (desc)) != 0) return (EFAULT); return (0); } case DTRACEIOC_GO: { processorid_t cpuid; rval = dtrace_state_go(state, &cpuid); if (rval != 0) return (rval); if (copyout(&cpuid, arg, sizeof (cpuid)) != 0) return (EFAULT); return (0); } case DTRACEIOC_STOP: { processorid_t cpuid; lck_mtx_lock(&dtrace_lock); rval = dtrace_state_stop(state, &cpuid); lck_mtx_unlock(&dtrace_lock); if (rval != 0) return (rval); if (copyout(&cpuid, arg, sizeof (cpuid)) != 0) return (EFAULT); return (0); } case DTRACEIOC_DOFGET: { dof_hdr_t hdr, *dof; uint64_t len; if (copyin(arg, &hdr, sizeof (hdr)) != 0) return (EFAULT); lck_mtx_lock(&dtrace_lock); dof = dtrace_dof_create(state); lck_mtx_unlock(&dtrace_lock); len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz); rval = copyout(dof, arg, len); dtrace_dof_destroy(dof); return (rval == 0 ? 0 : EFAULT); } case DTRACEIOC_AGGSNAP: case DTRACEIOC_BUFSNAP: { dtrace_bufdesc_t desc; caddr_t cached; dtrace_buffer_t *buf; if (copyin(arg, &desc, sizeof (desc)) != 0) return (EFAULT); if ((int)desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU) return (EINVAL); lck_mtx_lock(&dtrace_lock); if (cmd == DTRACEIOC_BUFSNAP) { buf = &state->dts_buffer[desc.dtbd_cpu]; } else { buf = &state->dts_aggbuffer[desc.dtbd_cpu]; } if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) { size_t sz = buf->dtb_offset; if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) { lck_mtx_unlock(&dtrace_lock); return (EBUSY); } /* * If this buffer has already been consumed, we're * going to indicate that there's nothing left here * to consume. */ if (buf->dtb_flags & DTRACEBUF_CONSUMED) { lck_mtx_unlock(&dtrace_lock); desc.dtbd_size = 0; desc.dtbd_drops = 0; desc.dtbd_errors = 0; desc.dtbd_oldest = 0; sz = sizeof (desc); if (copyout(&desc, arg, sz) != 0) return (EFAULT); return (0); } /* * If this is a ring buffer that has wrapped, we want * to copy the whole thing out. */ if (buf->dtb_flags & DTRACEBUF_WRAPPED) { dtrace_buffer_polish(buf); sz = buf->dtb_size; } if (copyout(buf->dtb_tomax, (user_addr_t)desc.dtbd_data, sz) != 0) { lck_mtx_unlock(&dtrace_lock); return (EFAULT); } desc.dtbd_size = sz; desc.dtbd_drops = buf->dtb_drops; desc.dtbd_errors = buf->dtb_errors; desc.dtbd_oldest = buf->dtb_xamot_offset; lck_mtx_unlock(&dtrace_lock); if (copyout(&desc, arg, sizeof (desc)) != 0) return (EFAULT); buf->dtb_flags |= DTRACEBUF_CONSUMED; return (0); } if (buf->dtb_tomax == NULL) { ASSERT(buf->dtb_xamot == NULL); lck_mtx_unlock(&dtrace_lock); return (ENOENT); } cached = buf->dtb_tomax; ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH)); dtrace_xcall(desc.dtbd_cpu, (dtrace_xcall_t)dtrace_buffer_switch, buf); state->dts_errors += buf->dtb_xamot_errors; /* * If the buffers did not actually switch, then the cross call * did not take place -- presumably because the given CPU is * not in the ready set. If this is the case, we'll return * ENOENT. */ if (buf->dtb_tomax == cached) { ASSERT(buf->dtb_xamot != cached); lck_mtx_unlock(&dtrace_lock); return (ENOENT); } ASSERT(cached == buf->dtb_xamot); /* * We have our snapshot; now copy it out. */ if (copyout(buf->dtb_xamot, (user_addr_t)desc.dtbd_data, buf->dtb_xamot_offset) != 0) { lck_mtx_unlock(&dtrace_lock); return (EFAULT); } desc.dtbd_size = buf->dtb_xamot_offset; desc.dtbd_drops = buf->dtb_xamot_drops; desc.dtbd_errors = buf->dtb_xamot_errors; desc.dtbd_oldest = 0; lck_mtx_unlock(&dtrace_lock); /* * Finally, copy out the buffer description. */ if (copyout(&desc, arg, sizeof (desc)) != 0) return (EFAULT); return (0); } case DTRACEIOC_CONF: { dtrace_conf_t conf; bzero(&conf, sizeof (conf)); conf.dtc_difversion = DIF_VERSION; conf.dtc_difintregs = DIF_DIR_NREGS; conf.dtc_diftupregs = DIF_DTR_NREGS; conf.dtc_ctfmodel = CTF_MODEL_NATIVE; if (copyout(&conf, arg, sizeof (conf)) != 0) return (EFAULT); return (0); } case DTRACEIOC_STATUS: { dtrace_status_t stat; dtrace_dstate_t *dstate; int i, j; uint64_t nerrs; /* * See the comment in dtrace_state_deadman() for the reason * for setting dts_laststatus to INT64_MAX before setting * it to the correct value. */ state->dts_laststatus = INT64_MAX; dtrace_membar_producer(); state->dts_laststatus = dtrace_gethrtime(); bzero(&stat, sizeof (stat)); lck_mtx_lock(&dtrace_lock); if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) { lck_mtx_unlock(&dtrace_lock); return (ENOENT); } if (state->dts_activity == DTRACE_ACTIVITY_DRAINING) stat.dtst_exiting = 1; nerrs = state->dts_errors; dstate = &state->dts_vstate.dtvs_dynvars; for (i = 0; i < (int)NCPU; i++) { dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i]; stat.dtst_dyndrops += dcpu->dtdsc_drops; stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops; stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops; if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL) stat.dtst_filled++; nerrs += state->dts_buffer[i].dtb_errors; for (j = 0; j < state->dts_nspeculations; j++) { dtrace_speculation_t *spec; dtrace_buffer_t *buf; spec = &state->dts_speculations[j]; buf = &spec->dtsp_buffer[i]; stat.dtst_specdrops += buf->dtb_xamot_drops; } } stat.dtst_specdrops_busy = state->dts_speculations_busy; stat.dtst_specdrops_unavail = state->dts_speculations_unavail; stat.dtst_stkstroverflows = state->dts_stkstroverflows; stat.dtst_dblerrors = state->dts_dblerrors; stat.dtst_killed = (state->dts_activity == DTRACE_ACTIVITY_KILLED); stat.dtst_errors = nerrs; lck_mtx_unlock(&dtrace_lock); if (copyout(&stat, arg, sizeof (stat)) != 0) return (EFAULT); return (0); } case DTRACEIOC_FORMAT: { dtrace_fmtdesc_t fmt; char *str; int len; if (copyin(arg, &fmt, sizeof (fmt)) != 0) return (EFAULT); lck_mtx_lock(&dtrace_lock); if (fmt.dtfd_format == 0 || fmt.dtfd_format > state->dts_nformats) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } /* * Format strings are allocated contiguously and they are * never freed; if a format index is less than the number * of formats, we can assert that the format map is non-NULL * and that the format for the specified index is non-NULL. */ ASSERT(state->dts_formats != NULL); str = state->dts_formats[fmt.dtfd_format - 1]; ASSERT(str != NULL); len = strlen(str) + 1; if (len > fmt.dtfd_length) { fmt.dtfd_length = len; if (copyout(&fmt, arg, sizeof (fmt)) != 0) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } } else { if (copyout(str, (user_addr_t)fmt.dtfd_string, len) != 0) { lck_mtx_unlock(&dtrace_lock); return (EINVAL); } } lck_mtx_unlock(&dtrace_lock); return (0); } case DTRACEIOC_MODUUIDSLIST: { size_t module_uuids_list_size; dtrace_module_uuids_list_t* uuids_list; uint64_t dtmul_count; /* * Security restrictions make this operation illegal, if this is enabled DTrace * must refuse to provide any fbt probes. */ if (dtrace_is_restricted()) { cmn_err(CE_WARN, "security restrictions disallow DTRACEIOC_MODUUIDSLIST"); return (EPERM); } /* * Fail if the kernel symbol mode makes this operation illegal. * Both NEVER & ALWAYS_FROM_KERNEL are permanent states, it is legal to check * for them without holding the dtrace_lock. */ if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_NEVER || dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_ALWAYS_FROM_KERNEL) { cmn_err(CE_WARN, "dtrace_kernel_symbol_mode of %u disallows DTRACEIOC_MODUUIDSLIST", dtrace_kernel_symbol_mode); return (EPERM); } /* * Read the number of symbolsdesc structs being passed in. */ if (copyin(arg + offsetof(dtrace_module_uuids_list_t, dtmul_count), &dtmul_count, sizeof(dtmul_count))) { cmn_err(CE_WARN, "failed to copyin dtmul_count"); return (EFAULT); } /* * Range check the count. More than 2k kexts is probably an error. */ if (dtmul_count > 2048) { cmn_err(CE_WARN, "dtmul_count is not valid"); return (EINVAL); } /* * For all queries, we return EINVAL when the user specified * count does not match the actual number of modules we find * available. * * If the user specified count is zero, then this serves as a * simple query to count the available modules in need of symbols. */ rval = 0; if (dtmul_count == 0) { lck_mtx_lock(&mod_lock); struct modctl* ctl = dtrace_modctl_list; while (ctl) { /* Update the private probes bit */ if (dtrace_provide_private_probes) ctl->mod_flags |= MODCTL_FBT_PROVIDE_PRIVATE_PROBES; ASSERT(!MOD_HAS_USERSPACE_SYMBOLS(ctl)); if (!MOD_SYMBOLS_DONE(ctl)) { dtmul_count++; rval = EINVAL; } ctl = ctl->mod_next; } lck_mtx_unlock(&mod_lock); if (copyout(&dtmul_count, arg, sizeof (dtmul_count)) != 0) return (EFAULT); else return (rval); } /* * If we reach this point, then we have a request for full list data. * Allocate a correctly sized structure and copyin the data. */ module_uuids_list_size = DTRACE_MODULE_UUIDS_LIST_SIZE(dtmul_count); if ((uuids_list = kmem_alloc(module_uuids_list_size, KM_SLEEP)) == NULL) return (ENOMEM); /* NOTE! We can no longer exit this method via return */ if (copyin(arg, uuids_list, module_uuids_list_size) != 0) { cmn_err(CE_WARN, "failed copyin of dtrace_module_uuids_list_t"); rval = EFAULT; goto moduuidslist_cleanup; } /* * Check that the count didn't change between the first copyin and the second. */ if (uuids_list->dtmul_count != dtmul_count) { rval = EINVAL; goto moduuidslist_cleanup; } /* * Build the list of UUID's that need symbols */ lck_mtx_lock(&mod_lock); dtmul_count = 0; struct modctl* ctl = dtrace_modctl_list; while (ctl) { /* Update the private probes bit */ if (dtrace_provide_private_probes) ctl->mod_flags |= MODCTL_FBT_PROVIDE_PRIVATE_PROBES; /* * We assume that userspace symbols will be "better" than kernel level symbols, * as userspace can search for dSYM(s) and symbol'd binaries. Even if kernel syms * are available, add user syms if the module might use them. */ ASSERT(!MOD_HAS_USERSPACE_SYMBOLS(ctl)); if (!MOD_SYMBOLS_DONE(ctl)) { UUID* uuid = &uuids_list->dtmul_uuid[dtmul_count]; if (dtmul_count++ < uuids_list->dtmul_count) { memcpy(uuid, ctl->mod_uuid, sizeof(UUID)); } } ctl = ctl->mod_next; } lck_mtx_unlock(&mod_lock); if (uuids_list->dtmul_count < dtmul_count) rval = EINVAL; uuids_list->dtmul_count = dtmul_count; /* * Copyout the symbols list (or at least the count!) */ if (copyout(uuids_list, arg, module_uuids_list_size) != 0) { cmn_err(CE_WARN, "failed copyout of dtrace_symbolsdesc_list_t"); rval = EFAULT; } moduuidslist_cleanup: /* * If we had to allocate struct memory, free it. */ if (uuids_list != NULL) { kmem_free(uuids_list, module_uuids_list_size); } return rval; } case DTRACEIOC_PROVMODSYMS: { size_t module_symbols_size; dtrace_module_symbols_t* module_symbols; uint64_t dtmodsyms_count; /* * Security restrictions make this operation illegal, if this is enabled DTrace * must refuse to provide any fbt probes. */ if (dtrace_is_restricted()) { cmn_err(CE_WARN, "security restrictions disallow DTRACEIOC_MODUUIDSLIST"); return (EPERM); } /* * Fail if the kernel symbol mode makes this operation illegal. * Both NEVER & ALWAYS_FROM_KERNEL are permanent states, it is legal to check * for them without holding the dtrace_lock. */ if (dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_NEVER || dtrace_kernel_symbol_mode == DTRACE_KERNEL_SYMBOLS_ALWAYS_FROM_KERNEL) { cmn_err(CE_WARN, "dtrace_kernel_symbol_mode of %u disallows DTRACEIOC_PROVMODSYMS", dtrace_kernel_symbol_mode); return (EPERM); } /* * Read the number of module symbols structs being passed in. */ if (copyin(arg + offsetof(dtrace_module_symbols_t, dtmodsyms_count), &dtmodsyms_count, sizeof(dtmodsyms_count))) { cmn_err(CE_WARN, "failed to copyin dtmodsyms_count"); return (EFAULT); } /* * Range check the count. How much data can we pass around? * FIX ME! */ if (dtmodsyms_count == 0 || (dtmodsyms_count > 100 * 1024)) { cmn_err(CE_WARN, "dtmodsyms_count is not valid"); return (EINVAL); } /* * Allocate a correctly sized structure and copyin the data. */ module_symbols_size = DTRACE_MODULE_SYMBOLS_SIZE(dtmodsyms_count); if ((module_symbols = kmem_alloc(module_symbols_size, KM_SLEEP)) == NULL) return (ENOMEM); rval = 0; /* NOTE! We can no longer exit this method via return */ if (copyin(arg, module_symbols, module_symbols_size) != 0) { cmn_err(CE_WARN, "failed copyin of dtrace_module_symbols_t, symbol count %llu", module_symbols->dtmodsyms_count); rval = EFAULT; goto module_symbols_cleanup; } /* * Check that the count didn't change between the first copyin and the second. */ if (module_symbols->dtmodsyms_count != dtmodsyms_count) { rval = EINVAL; goto module_symbols_cleanup; } /* * Find the modctl to add symbols to. */ lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&mod_lock); struct modctl* ctl = dtrace_modctl_list; while (ctl) { /* Update the private probes bit */ if (dtrace_provide_private_probes) ctl->mod_flags |= MODCTL_FBT_PROVIDE_PRIVATE_PROBES; ASSERT(!MOD_HAS_USERSPACE_SYMBOLS(ctl)); if (MOD_HAS_UUID(ctl) && !MOD_SYMBOLS_DONE(ctl)) { if (memcmp(module_symbols->dtmodsyms_uuid, ctl->mod_uuid, sizeof(UUID)) == 0) { /* BINGO! */ ctl->mod_user_symbols = module_symbols; break; } } ctl = ctl->mod_next; } if (ctl) { dtrace_provider_t *prv; /* * We're going to call each providers per-module provide operation * specifying only this module. */ for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next) prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl); /* * We gave every provider a chance to provide with the user syms, go ahead and clear them */ ctl->mod_user_symbols = NULL; /* MUST reset this to clear HAS_USERSPACE_SYMBOLS */ } lck_mtx_unlock(&mod_lock); lck_mtx_unlock(&dtrace_provider_lock); module_symbols_cleanup: /* * If we had to allocate struct memory, free it. */ if (module_symbols != NULL) { kmem_free(module_symbols, module_symbols_size); } return rval; } case DTRACEIOC_PROCWAITFOR: { dtrace_procdesc_t pdesc = { .p_comm = {0}, .p_pid = -1 }; if ((rval = copyin(arg, &pdesc, sizeof(pdesc))) != 0) goto proc_waitfor_error; if ((rval = dtrace_proc_waitfor(&pdesc)) != 0) goto proc_waitfor_error; if ((rval = copyout(&pdesc, arg, sizeof(pdesc))) != 0) goto proc_waitfor_error; return 0; proc_waitfor_error: /* The process was suspended, revert this since the client will not do it. */ if (pdesc.p_pid != -1) { proc_t *proc = proc_find(pdesc.p_pid); if (proc != PROC_NULL) { task_pidresume(proc->task); proc_rele(proc); } } return rval; } default: break; } return (ENOTTY); } /* * APPLE NOTE: dtrace_detach not implemented */ #if !defined(__APPLE__) /*ARGSUSED*/ static int dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd) { dtrace_state_t *state; switch (cmd) { case DDI_DETACH: break; case DDI_SUSPEND: return (DDI_SUCCESS); default: return (DDI_FAILURE); } lck_mtx_lock(&cpu_lock); lck_mtx_lock(&dtrace_provider_lock); lck_mtx_lock(&dtrace_lock); ASSERT(dtrace_opens == 0); if (dtrace_helpers > 0) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); lck_mtx_unlock(&cpu_lock); return (DDI_FAILURE); } if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) { lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); lck_mtx_unlock(&cpu_lock); return (DDI_FAILURE); } dtrace_provider = NULL; if ((state = dtrace_anon_grab()) != NULL) { /* * If there were ECBs on this state, the provider should * have not been allowed to detach; assert that there is * none. */ ASSERT(state->dts_necbs == 0); dtrace_state_destroy(state); /* * If we're being detached with anonymous state, we need to * indicate to the kernel debugger that DTrace is now inactive. */ (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE); } bzero(&dtrace_anon, sizeof (dtrace_anon_t)); unregister_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL); dtrace_cpu_init = NULL; dtrace_helpers_cleanup = NULL; dtrace_helpers_fork = NULL; dtrace_cpustart_init = NULL; dtrace_cpustart_fini = NULL; dtrace_debugger_init = NULL; dtrace_debugger_fini = NULL; dtrace_kreloc_init = NULL; dtrace_kreloc_fini = NULL; dtrace_modload = NULL; dtrace_modunload = NULL; lck_mtx_unlock(&cpu_lock); if (dtrace_helptrace_enabled) { kmem_free(dtrace_helptrace_buffer, dtrace_helptrace_bufsize); dtrace_helptrace_buffer = NULL; } kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *)); dtrace_probes = NULL; dtrace_nprobes = 0; dtrace_hash_destroy(dtrace_bymod); dtrace_hash_destroy(dtrace_byfunc); dtrace_hash_destroy(dtrace_byname); dtrace_bymod = NULL; dtrace_byfunc = NULL; dtrace_byname = NULL; kmem_cache_destroy(dtrace_state_cache); vmem_destroy(dtrace_minor); vmem_destroy(dtrace_arena); if (dtrace_toxrange != NULL) { kmem_free(dtrace_toxrange, dtrace_toxranges_max * sizeof (dtrace_toxrange_t)); dtrace_toxrange = NULL; dtrace_toxranges = 0; dtrace_toxranges_max = 0; } ddi_remove_minor_node(dtrace_devi, NULL); dtrace_devi = NULL; ddi_soft_state_fini(&dtrace_softstate); ASSERT(dtrace_vtime_references == 0); ASSERT(dtrace_opens == 0); ASSERT(dtrace_retained == NULL); lck_mtx_unlock(&dtrace_lock); lck_mtx_unlock(&dtrace_provider_lock); /* * We don't destroy the task queue until after we have dropped our * locks (taskq_destroy() may block on running tasks). To prevent * attempting to do work after we have effectively detached but before * the task queue has been destroyed, all tasks dispatched via the * task queue must check that DTrace is still attached before * performing any operation. */ taskq_destroy(dtrace_taskq); dtrace_taskq = NULL; return (DDI_SUCCESS); } #endif /* __APPLE__ */ d_open_t _dtrace_open, helper_open; d_close_t _dtrace_close, helper_close; d_ioctl_t _dtrace_ioctl, helper_ioctl; int _dtrace_open(dev_t dev, int flags, int devtype, struct proc *p) { #pragma unused(p) dev_t locdev = dev; return dtrace_open( &locdev, flags, devtype, CRED()); } int helper_open(dev_t dev, int flags, int devtype, struct proc *p) { #pragma unused(dev,flags,devtype,p) return 0; } int _dtrace_close(dev_t dev, int flags, int devtype, struct proc *p) { #pragma unused(p) return dtrace_close( dev, flags, devtype, CRED()); } int helper_close(dev_t dev, int flags, int devtype, struct proc *p) { #pragma unused(dev,flags,devtype,p) return 0; } int _dtrace_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct proc *p) { #pragma unused(p) int err, rv = 0; user_addr_t uaddrp; if (proc_is64bit(p)) uaddrp = *(user_addr_t *)data; else uaddrp = (user_addr_t) *(uint32_t *)data; err = dtrace_ioctl(dev, cmd, uaddrp, fflag, CRED(), &rv); /* Darwin's BSD ioctls only return -1 or zero. Overload errno to mimic Solaris. 20 bits suffice. */ if (err != 0) { ASSERT( (err & 0xfffff000) == 0 ); return (err & 0xfff); /* ioctl will return -1 and will set errno to an error code < 4096 */ } else if (rv != 0) { ASSERT( (rv & 0xfff00000) == 0 ); return (((rv & 0xfffff) << 12)); /* ioctl will return -1 and will set errno to a value >= 4096 */ } else return 0; } int helper_ioctl(dev_t dev, u_long cmd, caddr_t data, int fflag, struct proc *p) { #pragma unused(dev,fflag,p) int err, rv = 0; err = dtrace_ioctl_helper(cmd, data, &rv); /* Darwin's BSD ioctls only return -1 or zero. Overload errno to mimic Solaris. 20 bits suffice. */ if (err != 0) { ASSERT( (err & 0xfffff000) == 0 ); return (err & 0xfff); /* ioctl will return -1 and will set errno to an error code < 4096 */ } else if (rv != 0) { ASSERT( (rv & 0xfff00000) == 0 ); return (((rv & 0xfffff) << 12)); /* ioctl will return -1 and will set errno to a value >= 4096 */ } else return 0; } #define HELPER_MAJOR -24 /* let the kernel pick the device number */ /* * A struct describing which functions will get invoked for certain * actions. */ static struct cdevsw helper_cdevsw = { helper_open, /* open */ helper_close, /* close */ eno_rdwrt, /* read */ eno_rdwrt, /* write */ helper_ioctl, /* ioctl */ (stop_fcn_t *)nulldev, /* stop */ (reset_fcn_t *)nulldev, /* reset */ NULL, /* tty's */ eno_select, /* select */ eno_mmap, /* mmap */ eno_strat, /* strategy */ eno_getc, /* getc */ eno_putc, /* putc */ 0 /* type */ }; static int helper_majdevno = 0; static int gDTraceInited = 0; void helper_init( void ) { /* * Once the "helper" is initialized, it can take ioctl calls that use locks * and zones initialized in dtrace_init. Make certain dtrace_init was called * before us. */ if (!gDTraceInited) { panic("helper_init before dtrace_init\n"); } if (0 >= helper_majdevno) { helper_majdevno = cdevsw_add(HELPER_MAJOR, &helper_cdevsw); if (helper_majdevno < 0) { printf("helper_init: failed to allocate a major number!\n"); return; } if (NULL == devfs_make_node( makedev(helper_majdevno, 0), DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0666, DTRACEMNR_HELPER, 0 )) { printf("dtrace_init: failed to devfs_make_node for helper!\n"); return; } } else panic("helper_init: called twice!\n"); } #undef HELPER_MAJOR /* * Called with DEVFS_LOCK held, so vmem_alloc's underlying blist structures are protected. */ static int dtrace_clone_func(dev_t dev, int action) { #pragma unused(dev) if (action == DEVFS_CLONE_ALLOC) { if (NULL == dtrace_minor) /* Arena not created yet!?! */ return 0; else { /* * Propose a minor number, namely the next number that vmem_alloc() will return. * Immediately put it back in play by calling vmem_free(). FIXME. */ int ret = (int)(uintptr_t)vmem_alloc(dtrace_minor, 1, VM_BESTFIT | VM_SLEEP); vmem_free(dtrace_minor, (void *)(uintptr_t)ret, 1); return ret; } } else if (action == DEVFS_CLONE_FREE) { return 0; } else return -1; } #define DTRACE_MAJOR -24 /* let the kernel pick the device number */ static struct cdevsw dtrace_cdevsw = { _dtrace_open, /* open */ _dtrace_close, /* close */ eno_rdwrt, /* read */ eno_rdwrt, /* write */ _dtrace_ioctl, /* ioctl */ (stop_fcn_t *)nulldev, /* stop */ (reset_fcn_t *)nulldev, /* reset */ NULL, /* tty's */ eno_select, /* select */ eno_mmap, /* mmap */ eno_strat, /* strategy */ eno_getc, /* getc */ eno_putc, /* putc */ 0 /* type */ }; lck_attr_t* dtrace_lck_attr; lck_grp_attr_t* dtrace_lck_grp_attr; lck_grp_t* dtrace_lck_grp; static int gMajDevNo; void dtrace_init( void ) { if (0 == gDTraceInited) { int i, ncpu; size_t size = sizeof(dtrace_buffer_memory_maxsize); /* * DTrace allocates buffers based on the maximum number * of enabled cpus. This call avoids any race when finding * that count. */ ASSERT(dtrace_max_cpus == 0); ncpu = dtrace_max_cpus = ml_get_max_cpus(); /* * Retrieve the size of the physical memory in order to define * the state buffer memory maximal size. If we cannot retrieve * this value, we'll consider that we have 1Gb of memory per CPU, that's * still better than raising a kernel panic. */ if (0 != kernel_sysctlbyname("hw.memsize", &dtrace_buffer_memory_maxsize, &size, NULL, 0)) { dtrace_buffer_memory_maxsize = ncpu * 1024 * 1024 * 1024; printf("dtrace_init: failed to retrieve the hw.memsize, defaulted to %lld bytes\n", dtrace_buffer_memory_maxsize); } /* * Finally, divide by three to prevent DTrace from eating too * much memory. */ dtrace_buffer_memory_maxsize /= 3; ASSERT(dtrace_buffer_memory_maxsize > 0); gMajDevNo = cdevsw_add(DTRACE_MAJOR, &dtrace_cdevsw); if (gMajDevNo < 0) { printf("dtrace_init: failed to allocate a major number!\n"); gDTraceInited = 0; return; } if (NULL == devfs_make_node_clone( makedev(gMajDevNo, 0), DEVFS_CHAR, UID_ROOT, GID_WHEEL, 0666, dtrace_clone_func, DTRACEMNR_DTRACE, 0 )) { printf("dtrace_init: failed to devfs_make_node_clone for dtrace!\n"); gDTraceInited = 0; return; } #if defined(DTRACE_MEMORY_ZONES) /* * Initialize the dtrace kalloc-emulation zones. */ dtrace_alloc_init(); #endif /* DTRACE_MEMORY_ZONES */ /* * Allocate the dtrace_probe_t zone */ dtrace_probe_t_zone = zinit(sizeof(dtrace_probe_t), 1024 * sizeof(dtrace_probe_t), sizeof(dtrace_probe_t), "dtrace.dtrace_probe_t"); /* * Create the dtrace lock group and attrs. */ dtrace_lck_attr = lck_attr_alloc_init(); dtrace_lck_grp_attr= lck_grp_attr_alloc_init(); dtrace_lck_grp = lck_grp_alloc_init("dtrace", dtrace_lck_grp_attr); /* * We have to initialize all locks explicitly */ lck_mtx_init(&dtrace_lock, dtrace_lck_grp, dtrace_lck_attr); lck_mtx_init(&dtrace_provider_lock, dtrace_lck_grp, dtrace_lck_attr); lck_mtx_init(&dtrace_meta_lock, dtrace_lck_grp, dtrace_lck_attr); lck_mtx_init(&dtrace_procwaitfor_lock, dtrace_lck_grp, dtrace_lck_attr); #if DEBUG lck_mtx_init(&dtrace_errlock, dtrace_lck_grp, dtrace_lck_attr); #endif lck_rw_init(&dtrace_dof_mode_lock, dtrace_lck_grp, dtrace_lck_attr); /* * The cpu_core structure consists of per-CPU state available in any context. * On some architectures, this may mean that the page(s) containing the * NCPU-sized array of cpu_core structures must be locked in the TLB -- it * is up to the platform to assure that this is performed properly. Note that * the structure is sized to avoid false sharing. */ lck_mtx_init(&cpu_lock, dtrace_lck_grp, dtrace_lck_attr); lck_mtx_init(&cyc_lock, dtrace_lck_grp, dtrace_lck_attr); lck_mtx_init(&mod_lock, dtrace_lck_grp, dtrace_lck_attr); /* * Initialize the CPU offline/online hooks. */ dtrace_install_cpu_hooks(); dtrace_modctl_list = NULL; cpu_core = (cpu_core_t *)kmem_zalloc( ncpu * sizeof(cpu_core_t), KM_SLEEP ); for (i = 0; i < ncpu; ++i) { lck_mtx_init(&cpu_core[i].cpuc_pid_lock, dtrace_lck_grp, dtrace_lck_attr); } cpu_list = (dtrace_cpu_t *)kmem_zalloc( ncpu * sizeof(dtrace_cpu_t), KM_SLEEP ); for (i = 0; i < ncpu; ++i) { cpu_list[i].cpu_id = (processorid_t)i; cpu_list[i].cpu_next = &(cpu_list[(i+1) % ncpu]); LIST_INIT(&cpu_list[i].cpu_cyc_list); lck_rw_init(&cpu_list[i].cpu_ft_lock, dtrace_lck_grp, dtrace_lck_attr); } lck_mtx_lock(&cpu_lock); for (i = 0; i < ncpu; ++i) /* FIXME: track CPU configuration a la CHUD Processor Pref Pane. */ dtrace_cpu_setup_initial( (processorid_t)i ); /* In lieu of register_cpu_setup_func() callback */ lck_mtx_unlock(&cpu_lock); (void)dtrace_abs_to_nano(0LL); /* Force once only call to clock_timebase_info (which can take a lock) */ dtrace_isa_init(); /* * See dtrace_impl.h for a description of dof modes. * The default is lazy dof. * * FIXME: Warn if state is LAZY_OFF? It won't break anything, but * makes no sense... */ if (!PE_parse_boot_argn("dtrace_dof_mode", &dtrace_dof_mode, sizeof (dtrace_dof_mode))) { dtrace_dof_mode = DTRACE_DOF_MODE_LAZY_ON; } /* * Sanity check of dof mode value. */ switch (dtrace_dof_mode) { case DTRACE_DOF_MODE_NEVER: case DTRACE_DOF_MODE_LAZY_ON: /* valid modes, but nothing else we need to do */ break; case DTRACE_DOF_MODE_LAZY_OFF: case DTRACE_DOF_MODE_NON_LAZY: /* Cannot wait for a dtrace_open to init fasttrap */ fasttrap_init(); break; default: /* Invalid, clamp to non lazy */ dtrace_dof_mode = DTRACE_DOF_MODE_NON_LAZY; fasttrap_init(); break; } /* * See dtrace_impl.h for a description of kernel symbol modes. * The default is to wait for symbols from userspace (lazy symbols). */ if (!PE_parse_boot_argn("dtrace_kernel_symbol_mode", &dtrace_kernel_symbol_mode, sizeof (dtrace_kernel_symbol_mode))) { dtrace_kernel_symbol_mode = DTRACE_KERNEL_SYMBOLS_FROM_USERSPACE; } gDTraceInited = 1; } else panic("dtrace_init: called twice!\n"); } void dtrace_postinit(void) { /* * Called from bsd_init after all provider's *_init() routines have been * run. That way, anonymous DOF enabled under dtrace_attach() is safe * to go. */ dtrace_attach( (dev_info_t *)(uintptr_t)makedev(gMajDevNo, 0), 0 ); /* Punning a dev_t to a dev_info_t* */ /* * Add the mach_kernel to the module list for lazy processing */ struct kmod_info fake_kernel_kmod; memset(&fake_kernel_kmod, 0, sizeof(fake_kernel_kmod)); strlcpy(fake_kernel_kmod.name, "mach_kernel", sizeof(fake_kernel_kmod.name)); fake_kernel_kmod.id = 1; fake_kernel_kmod.address = g_kernel_kmod_info.address; fake_kernel_kmod.size = g_kernel_kmod_info.size; if (dtrace_module_loaded(&fake_kernel_kmod, 0) != 0) { printf("dtrace_postinit: Could not register mach_kernel modctl\n"); } (void)OSKextRegisterKextsWithDTrace(); } #undef DTRACE_MAJOR /* * Routines used to register interest in cpu's being added to or removed * from the system. */ void register_cpu_setup_func(cpu_setup_func_t *ignore1, void *ignore2) { #pragma unused(ignore1,ignore2) } void unregister_cpu_setup_func(cpu_setup_func_t *ignore1, void *ignore2) { #pragma unused(ignore1,ignore2) }