/* $NetBSD: trap.c,v 1.17 2003/09/25 18:42:18 matt Exp $ */ /* * Copyright 2001 Wasabi Systems, Inc. * All rights reserved. * * Written by Eduardo Horvath and Simon Burge for Wasabi Systems, Inc. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed for the NetBSD Project by * Wasabi Systems, Inc. * 4. The name of Wasabi Systems, Inc. may not be used to endorse * or promote products derived from this software without specific prior * written permission. * * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ /* * Copyright (C) 1995, 1996 Wolfgang Solfrank. * Copyright (C) 1995, 1996 TooLs GmbH. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: trap.c,v 1.17 2003/09/25 18:42:18 matt Exp $"); #include "opt_altivec.h" #include "opt_ddb.h" #include "opt_ktrace.h" #include "opt_systrace.h" #include "opt_syscall_debug.h" #include #include #include #include #include #include #ifdef KTRACE #include #endif #include #include #include #ifdef SYSTRACE #include #endif #include #include #include #include #include #include #include #include #include #include #include #include #include /* These definitions should probably be somewhere else XXX */ #define FIRSTARG 3 /* first argument is in reg 3 */ #define NARGREG 8 /* 8 args are in registers */ #define MOREARGS(sp) ((caddr_t)((int)(sp) + 8)) /* more args go here */ static int fix_unaligned __P((struct lwp *l, struct trapframe *frame)); void trap __P((struct trapframe *)); /* Called from locore / trap_subr */ /* Why are these not defined in a header? */ int badaddr __P((void *, size_t)); int badaddr_read __P((void *, size_t, int *)); int ctx_setup __P((int, int)); #ifdef DEBUG #define TDB_ALL 0x1 int trapdebug = /* TDB_ALL */ 0; #define DBPRINTF(x, y) if (trapdebug & (x)) printf y #else #define DBPRINTF(x, y) #endif void trap(struct trapframe *frame) { struct lwp *l = curlwp; struct proc *p = l ? l->l_proc : NULL; int type = frame->exc; int ftype, rv; KASSERT(l == 0 || (l->l_stat == LSONPROC)); if (frame->srr1 & PSL_PR) type |= EXC_USER; ftype = VM_PROT_READ; DBPRINTF(TDB_ALL, ("trap(%x) at %lx from frame %p &frame %p\n", type, frame->srr0, frame, &frame)); switch (type) { case EXC_DEBUG|EXC_USER: { int srr2, srr3; __asm __volatile("mfspr %0,0x3f0" : "=r" (rv), "=r" (srr2), "=r" (srr3) :); printf("debug reg is %x srr2 %x srr3 %x\n", rv, srr2, srr3); /* XXX fall through or break here?! */ } /* * DEBUG intr -- probably single-step. */ case EXC_TRC|EXC_USER: frame->srr1 &= ~PSL_SE; memset(&ksi, 0, sizeof(ksi)); ksi.ksi_signo = SIGTRAP; ksi.ksi_trap = EXC_TRC; ksi.ksi_addr = (void *)frame->srr0; KERNEL_PROC_LOCK(l); trapsignal(l, &ksi); KERNEL_PROC_UNLOCK(l); break; /* * If we could not find and install appropriate TLB entry, fall through. */ case EXC_DSI: /* FALLTHROUGH */ case EXC_DTMISS: { struct vm_map *map; vaddr_t va; struct faultbuf *fb = NULL; KERNEL_LOCK(LK_CANRECURSE|LK_EXCLUSIVE); va = frame->dar; if (frame->tf_xtra[TF_PID] == KERNEL_PID) { map = kernel_map; } else { map = &p->p_vmspace->vm_map; if (l->l_flag & L_SA) { KDASSERT(p != NULL && p->p_sa != NULL); p->p_sa->sa_vp_faultaddr = va; l->l_flag |= L_SA_PAGEFAULT; } } if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) ftype = VM_PROT_WRITE; DBPRINTF(TDB_ALL, ("trap(EXC_DSI) at %lx %s fault on %p esr %x\n", frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", (void *)va, frame->tf_xtra[TF_ESR])); rv = uvm_fault(map, trunc_page(va), 0, ftype); KERNEL_UNLOCK(); if (map != kernel_map) l->l_flag &= ~L_SA_PAGEFAULT; if (rv == 0) goto done; if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { frame->tf_xtra[TF_PID] = KERNEL_PID; frame->srr0 = fb->fb_pc; frame->srr1 |= PSL_IR; /* Re-enable IMMU */ frame->fixreg[1] = fb->fb_sp; frame->fixreg[2] = fb->fb_r2; frame->fixreg[3] = 1; /* Return TRUE */ frame->cr = fb->fb_cr; memcpy(&frame->fixreg[13], fb->fb_fixreg, sizeof(fb->fb_fixreg)); goto done; } } goto brain_damage; case EXC_DSI|EXC_USER: /* FALLTHROUGH */ case EXC_DTMISS|EXC_USER: KERNEL_PROC_LOCK(l); if (frame->tf_xtra[TF_ESR] & (ESR_DST|ESR_DIZ)) ftype = VM_PROT_WRITE; DBPRINTF(TDB_ALL, ("trap(EXC_DSI|EXC_USER) at %lx %s fault on %lx %x\n", frame->srr0, (ftype & VM_PROT_WRITE) ? "write" : "read", frame->dar, frame->tf_xtra[TF_ESR])); KASSERT(l == curlwp && (l->l_stat == LSONPROC)); if (l->l_flag & L_SA) { KDASSERT(p != NULL && p->p_sa != NULL); p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->dar; l->l_flag |= L_SA_PAGEFAULT; } rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->dar), 0, ftype); if (rv == 0) { l->l_flag &= ~L_SA_PAGEFAULT; KERNEL_PROC_UNLOCK(l); break; } memset(&ksi, 0, sizeof(ksi)); ksi.ksi_signo = SIGSEGV; ksi.ksi_trap = EXC_DSI; ksi.ksi_addr = (void *)frame->dar; if (rv == ENOMEM) { printf("UVM: pid %d (%s) lid %d, uid %d killed: " "out of swap\n", p->p_pid, p->p_comm, l->l_lid, p->p_cred && p->p_ucred ? p->p_ucred->cr_uid : -1); ksi.ksi_signo = SIGKILL; } trapsignal(l, &ksi); l->l_flag &= ~L_SA_PAGEFAULT; KERNEL_PROC_UNLOCK(l); break; case EXC_ITMISS|EXC_USER: case EXC_ISI|EXC_USER: KERNEL_PROC_LOCK(l); if (l->l_flag & L_SA) { KDASSERT(p != NULL && p->p_sa != NULL); p->p_sa->sa_vp_faultaddr = (vaddr_t)frame->srr0; l->l_flag |= L_SA_PAGEFAULT; } ftype = VM_PROT_EXECUTE; DBPRINTF(TDB_ALL, ("trap(EXC_ISI|EXC_USER) at %lx execute fault tf %p\n", frame->srr0, frame)); rv = uvm_fault(&p->p_vmspace->vm_map, trunc_page(frame->srr0), 0, ftype); if (rv == 0) { l->l_flag &= ~L_SA_PAGEFAULT; KERNEL_PROC_UNLOCK(l); break; } memset(&ksi, 0, sizeof(ksi)); ksi.ksi_signo = SIGSEGV; ksi.ksi_trap = EXC_ISI; ksi.ksi_addr = (void *)frame->srr0; trapsignal(l, &ksi); l->l_flag &= ~L_SA_PAGEFAULT; KERNEL_PROC_UNLOCK(l); break; case EXC_AST|EXC_USER: curcpu()->ci_astpending = 0; /* we are about to do it */ KERNEL_PROC_LOCK(l); uvmexp.softs++; if (p->p_flag & P_OWEUPC) { p->p_flag &= ~P_OWEUPC; ADDUPROF(p); } /* Check whether we are being preempted. */ if (curcpu()->ci_want_resched) preempt(0); KERNEL_PROC_UNLOCK(l); break; case EXC_ALI|EXC_USER: KERNEL_PROC_LOCK(l); if (fix_unaligned(l, frame) != 0) { memset(&ksi, 0, sizeof(ksi)); ksi.ksi_signo = SIGBUS; ksi.ksi_trap = EXC_ALI; ksi.ksi_addr = (void *)frame->dar; trapsignal(l, &ksi); } else frame->srr0 += 4; KERNEL_PROC_UNLOCK(l); break; case EXC_PGM|EXC_USER: /* * Illegal insn: * * let's try to see if it's FPU and can be emulated. */ uvmexp.traps ++; if (!(l->l_addr->u_pcb.pcb_flags & PCB_FPU)) { memset(&l->l_addr->u_pcb.pcb_fpu, 0, sizeof l->l_addr->u_pcb.pcb_fpu); l->l_addr->u_pcb.pcb_flags |= PCB_FPU; } if ((rv = fpu_emulate(frame, (struct fpreg *)&l->l_addr->u_pcb.pcb_fpu))) { memset(&ksi, 0, sizeof(ksi)); ksi.ksi_signo = rv; ksi.ksi_trap = EXC_PGM; ksi.ksi_addr = (void *)frame->srr0; KERNEL_PROC_LOCK(l); trapsignal(l, &ksi); KERNEL_PROC_UNLOCK(l); } break; case EXC_MCHK: { struct faultbuf *fb; if ((fb = l->l_addr->u_pcb.pcb_onfault) != NULL) { frame->tf_xtra[TF_PID] = KERNEL_PID; frame->srr0 = fb->fb_pc; frame->srr1 |= PSL_IR; /* Re-enable IMMU */ frame->fixreg[1] = fb->fb_sp; frame->fixreg[2] = fb->fb_r2; frame->fixreg[3] = 1; /* Return TRUE */ frame->cr = fb->fb_cr; memcpy(&frame->fixreg[13], fb->fb_fixreg, sizeof(fb->fb_fixreg)); goto done; } } goto brain_damage; default: brain_damage: printf("trap type 0x%x at 0x%lx\n", type, frame->srr0); #ifdef DDB if (kdb_trap(type, frame)) goto done; #endif #ifdef TRAP_PANICWAIT printf("Press a key to panic.\n"); cngetc(); #endif panic("trap"); } /* Take pending signals. */ { int sig; while ((sig = CURSIG(l)) != 0) postsig(sig); } /* Invoke per-process kernel-exit handling, if any */ if (p->p_userret) (p->p_userret)(l, p->p_userret_arg); /* Invoke any pending upcalls */ while (l->l_flag & L_SA_UPCALL) sa_upcall_userret(l); curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; done: return; } int ctx_setup(int ctx, int srr1) { volatile struct pmap *pm; /* Update PID if we're returning to user mode. */ if (srr1 & PSL_PR) { pm = curproc->p_vmspace->vm_map.pmap; if (!pm->pm_ctx) { ctx_alloc((struct pmap *)pm); } ctx = pm->pm_ctx; if (srr1 & PSL_SE) { int dbreg, mask = 0x48000000; /* * Set the Internal Debug and * Instruction Completion bits of * the DBCR0 register. * * XXX this is also used by jtag debuggers... */ __asm __volatile("mfspr %0,0x3f2;" "or %0,%0,%1;" "mtspr 0x3f2,%0;" : "=&r" (dbreg) : "r" (mask)); } } else if (!ctx) { ctx = KERNEL_PID; } return (ctx); } /* * Used by copyin()/copyout() */ extern vaddr_t vmaprange __P((struct proc *, vaddr_t, vsize_t, int)); extern void vunmaprange __P((vaddr_t, vsize_t)); static int bigcopyin __P((const void *, void *, size_t )); static int bigcopyout __P((const void *, void *, size_t )); int copyin(const void *udaddr, void *kaddr, size_t len) { struct pmap *pm = curproc->p_vmspace->vm_map.pmap; int msr, pid, tmp, ctx; struct faultbuf env; /* For bigger buffers use the faster copy */ if (len > 256) return (bigcopyin(udaddr, kaddr, len)); if (setfault(&env)) { curpcb->pcb_onfault = 0; return EFAULT; } if (!(ctx = pm->pm_ctx)) { /* No context -- assign it one */ ctx_alloc(pm); ctx = pm->pm_ctx; } asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ "mfmsr %0;" /* Save MSR */ "li %1,0x20; " "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ "mfpid %1;" /* Save old PID */ "sync; isync;" "1: bdz 2f;" /* while len */ "mtpid %3; sync;" /* Load user ctx */ "lbz %2,0(%4); addi %4,%4,1;" /* Load byte */ "sync; isync;" "mtpid %1;sync;" "stb %2,0(%5); dcbf 0,%5; addi %5,%5,1;" /* Store kernel byte */ "sync; isync;" "b 1b;" /* repeat */ "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ "sync; isync;" : "=&r" (msr), "=&r" (pid), "=&r" (tmp) : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); curpcb->pcb_onfault = 0; return 0; } static int bigcopyin(const void *udaddr, void *kaddr, size_t len) { const char *up; char *kp = kaddr; struct lwp *l = curlwp; struct proc *p; int error; if (!l) { return EFAULT; } p = l->l_proc; /* * Stolen from physio(): */ PHOLD(l); error = uvm_vslock(p, (caddr_t)udaddr, len, VM_PROT_READ); if (error) { PRELE(l); return EFAULT; } up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ); memcpy(kp, up, len); vunmaprange((vaddr_t)up, len); uvm_vsunlock(p, (caddr_t)udaddr, len); PRELE(l); return 0; } int copyout(const void *kaddr, void *udaddr, size_t len) { struct pmap *pm = curproc->p_vmspace->vm_map.pmap; int msr, pid, tmp, ctx; struct faultbuf env; /* For big copies use more efficient routine */ if (len > 256) return (bigcopyout(kaddr, udaddr, len)); if (setfault(&env)) { curpcb->pcb_onfault = 0; return EFAULT; } if (!(ctx = pm->pm_ctx)) { /* No context -- assign it one */ ctx_alloc(pm); ctx = pm->pm_ctx; } asm volatile("addi %6,%6,1; mtctr %6;" /* Set up counter */ "mfmsr %0;" /* Save MSR */ "li %1,0x20; " "andc %1,%0,%1; mtmsr %1;" /* Disable IMMU */ "mfpid %1;" /* Save old PID */ "sync; isync;" "1: bdz 2f;" /* while len */ "mtpid %1;sync;" "lbz %2,0(%5); addi %5,%5,1;" /* Load kernel byte */ "sync; isync;" "mtpid %3; sync;" /* Load user ctx */ "stb %2,0(%4); dcbf 0,%4; addi %4,%4,1;" /* Store user byte */ "sync; isync;" "b 1b;" /* repeat */ "2: mtpid %1; mtmsr %0;" /* Restore PID and MSR */ "sync; isync;" : "=&r" (msr), "=&r" (pid), "=&r" (tmp) : "r" (ctx), "r" (udaddr), "r" (kaddr), "r" (len)); curpcb->pcb_onfault = 0; return 0; } static int bigcopyout(const void *kaddr, void *udaddr, size_t len) { char *up; const char *kp = (char *)kaddr; struct lwp *l = curlwp; struct proc *p; int error; if (!l) { return EFAULT; } p = l->l_proc; /* * Stolen from physio(): */ PHOLD(l); error = uvm_vslock(p, udaddr, len, VM_PROT_WRITE); if (error) { PRELE(l); return EFAULT; } up = (char *)vmaprange(p, (vaddr_t)udaddr, len, VM_PROT_READ | VM_PROT_WRITE); memcpy(up, kp, len); vunmaprange((vaddr_t)up, len); uvm_vsunlock(p, udaddr, len); PRELE(l); return 0; } /* * kcopy(const void *src, void *dst, size_t len); * * Copy len bytes from src to dst, aborting if we encounter a fatal * page fault. * * kcopy() _must_ save and restore the old fault handler since it is * called by uiomove(), which may be in the path of servicing a non-fatal * page fault. */ int kcopy(const void *src, void *dst, size_t len) { struct faultbuf env, *oldfault; oldfault = curpcb->pcb_onfault; if (setfault(&env)) { curpcb->pcb_onfault = oldfault; return EFAULT; } memcpy(dst, src, len); curpcb->pcb_onfault = oldfault; return 0; } int badaddr(void *addr, size_t size) { return badaddr_read(addr, size, NULL); } int badaddr_read(void *addr, size_t size, int *rptr) { struct faultbuf env; int x; /* Get rid of any stale machine checks that have been waiting. */ __asm __volatile ("sync; isync"); if (setfault(&env)) { curpcb->pcb_onfault = 0; __asm __volatile ("sync"); return 1; } __asm __volatile ("sync"); switch (size) { case 1: x = *(volatile int8_t *)addr; break; case 2: x = *(volatile int16_t *)addr; break; case 4: x = *(volatile int32_t *)addr; break; default: panic("badaddr: invalid size (%d)", size); } /* Make sure we took the machine check, if we caused one. */ __asm __volatile ("sync; isync"); curpcb->pcb_onfault = 0; __asm __volatile ("sync"); /* To be sure. */ /* Use the value to avoid reorder. */ if (rptr) *rptr = x; return 0; } /* * For now, this only deals with the particular unaligned access case * that gcc tends to generate. Eventually it should handle all of the * possibilities that can happen on a 32-bit PowerPC in big-endian mode. */ static int fix_unaligned(struct lwp *l, struct trapframe *frame) { return -1; } /* * Start a new LWP */ void startlwp(arg) void *arg; { int err; ucontext_t *uc = arg; struct lwp *l = curlwp; err = cpu_setmcontext(l, &uc->uc_mcontext, uc->uc_flags); #if DIAGNOSTIC if (err) { printf("Error %d from cpu_setmcontext.", err); } #endif pool_put(&lwp_uc_pool, uc); upcallret(l); } /* * XXX This is a terrible name. */ void upcallret(l) struct lwp *l; { int sig; /* Take pending signals. */ while ((sig = CURSIG(l)) != 0) postsig(sig); /* Invoke per-process kernel-exit handling, if any */ if (l->l_proc->p_userret) (l->l_proc->p_userret)(l, l->l_proc->p_userret_arg); /* Invoke any pending upcalls */ while (l->l_flag & L_SA_UPCALL) sa_upcall_userret(l); curcpu()->ci_schedstate.spc_curpriority = l->l_priority = l->l_usrpri; }