1/*- 2 * Copyright (c) 1992 Terrence R. Lambert. 3 * Copyright (c) 1982, 1987, 1990 The Regents of the University of California. 4 * All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * William Jolitz. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * from: @(#)machdep.c 7.4 (Berkeley) 6/3/91 34 * from: src/sys/i386/i386/machdep.c,v 1.385.2.3 2000/05/10 02:04:46 obrien 35 * JNPR: pm_machdep.c,v 1.9.2.1 2007/08/16 15:59:10 girish 36 */ 37 38#include <sys/cdefs.h> 39__FBSDID("$FreeBSD: releng/10.3/sys/mips/mips/pm_machdep.c 293581 2016-01-09 17:39:41Z dchagin $"); 40 41#include "opt_compat.h" 42 43#include <sys/types.h> 44#include <sys/param.h> 45#include <sys/systm.h> 46#include <sys/sysent.h> 47#include <sys/proc.h> 48#include <sys/signalvar.h> 49#include <sys/exec.h> 50#include <sys/imgact.h> 51#include <sys/ucontext.h> 52#include <sys/lock.h> 53#include <sys/syscallsubr.h> 54#include <sys/sysproto.h> 55#include <sys/ptrace.h> 56#include <sys/syslog.h> 57#include <vm/vm.h> 58#include <vm/pmap.h> 59#include <vm/vm_map.h> 60#include <vm/vm_extern.h> 61#include <sys/user.h> 62#include <sys/uio.h> 63#include <machine/reg.h> 64#include <machine/md_var.h> 65#include <machine/sigframe.h> 66#include <machine/vmparam.h> 67#include <sys/vnode.h> 68#include <fs/pseudofs/pseudofs.h> 69#include <fs/procfs/procfs.h> 70 71#define UCONTEXT_MAGIC 0xACEDBADE 72 73/* 74 * Send an interrupt to process. 75 * 76 * Stack is set up to allow sigcode stored 77 * at top to call routine, followed by kcall 78 * to sigreturn routine below. After sigreturn 79 * resets the signal mask, the stack, and the 80 * frame pointer, it returns to the user 81 * specified pc, psl. 82 */ 83void 84sendsig(sig_t catcher, ksiginfo_t *ksi, sigset_t *mask) 85{ 86 struct proc *p; 87 struct thread *td; 88 struct trapframe *regs; 89 struct sigacts *psp; 90 struct sigframe sf, *sfp; 91 int sig; 92 int oonstack; 93 94 td = curthread; 95 p = td->td_proc; 96 PROC_LOCK_ASSERT(p, MA_OWNED); 97 sig = ksi->ksi_signo; 98 psp = p->p_sigacts; 99 mtx_assert(&psp->ps_mtx, MA_OWNED); 100 101 regs = td->td_frame; 102 oonstack = sigonstack(regs->sp); 103 104 /* save user context */ 105 bzero(&sf, sizeof(struct sigframe)); 106 sf.sf_uc.uc_sigmask = *mask; 107 sf.sf_uc.uc_stack = td->td_sigstk; 108 sf.sf_uc.uc_mcontext.mc_onstack = (oonstack) ? 1 : 0; 109 sf.sf_uc.uc_mcontext.mc_pc = regs->pc; 110 sf.sf_uc.uc_mcontext.mullo = regs->mullo; 111 sf.sf_uc.uc_mcontext.mulhi = regs->mulhi; 112 sf.sf_uc.uc_mcontext.mc_tls = td->td_md.md_tls; 113 sf.sf_uc.uc_mcontext.mc_regs[0] = UCONTEXT_MAGIC; /* magic number */ 114 bcopy((void *)®s->ast, (void *)&sf.sf_uc.uc_mcontext.mc_regs[1], 115 sizeof(sf.sf_uc.uc_mcontext.mc_regs) - sizeof(register_t)); 116 sf.sf_uc.uc_mcontext.mc_fpused = td->td_md.md_flags & MDTD_FPUSED; 117 if (sf.sf_uc.uc_mcontext.mc_fpused) { 118 /* if FPU has current state, save it first */ 119 if (td == PCPU_GET(fpcurthread)) 120 MipsSaveCurFPState(td); 121 bcopy((void *)&td->td_frame->f0, 122 (void *)sf.sf_uc.uc_mcontext.mc_fpregs, 123 sizeof(sf.sf_uc.uc_mcontext.mc_fpregs)); 124 } 125 126 /* Allocate and validate space for the signal handler context. */ 127 if ((td->td_pflags & TDP_ALTSTACK) != 0 && !oonstack && 128 SIGISMEMBER(psp->ps_sigonstack, sig)) { 129 sfp = (struct sigframe *)((vm_offset_t)(td->td_sigstk.ss_sp + 130 td->td_sigstk.ss_size - sizeof(struct sigframe)) 131 & ~(sizeof(__int64_t) - 1)); 132 } else 133 sfp = (struct sigframe *)((vm_offset_t)(regs->sp - 134 sizeof(struct sigframe)) & ~(sizeof(__int64_t) - 1)); 135 136 /* Build the argument list for the signal handler. */ 137 regs->a0 = sig; 138 regs->a2 = (register_t)(intptr_t)&sfp->sf_uc; 139 if (SIGISMEMBER(psp->ps_siginfo, sig)) { 140 /* Signal handler installed with SA_SIGINFO. */ 141 regs->a1 = (register_t)(intptr_t)&sfp->sf_si; 142 /* sf.sf_ahu.sf_action = (__siginfohandler_t *)catcher; */ 143 144 /* fill siginfo structure */ 145 sf.sf_si.si_signo = sig; 146 sf.sf_si.si_code = ksi->ksi_code; 147 sf.sf_si.si_addr = (void*)(intptr_t)regs->badvaddr; 148 } else { 149 /* Old FreeBSD-style arguments. */ 150 regs->a1 = ksi->ksi_code; 151 regs->a3 = regs->badvaddr; 152 /* sf.sf_ahu.sf_handler = catcher; */ 153 } 154 155 mtx_unlock(&psp->ps_mtx); 156 PROC_UNLOCK(p); 157 158 /* 159 * Copy the sigframe out to the user's stack. 160 */ 161 if (copyout(&sf, sfp, sizeof(struct sigframe)) != 0) { 162 /* 163 * Something is wrong with the stack pointer. 164 * ...Kill the process. 165 */ 166 PROC_LOCK(p); 167 sigexit(td, SIGILL); 168 } 169 170 regs->pc = (register_t)(intptr_t)catcher; 171 regs->t9 = (register_t)(intptr_t)catcher; 172 regs->sp = (register_t)(intptr_t)sfp; 173 /* 174 * Signal trampoline code is at base of user stack. 175 */ 176 regs->ra = (register_t)(intptr_t)PS_STRINGS - *(p->p_sysent->sv_szsigcode); 177 PROC_LOCK(p); 178 mtx_lock(&psp->ps_mtx); 179} 180 181#ifdef GONE_IN_7 182/* 183 * Build siginfo_t for SA thread 184 */ 185void 186cpu_thread_siginfo(int sig, u_long code, siginfo_t *si) 187{ 188 struct proc *p; 189 struct thread *td; 190 191 td = curthread; 192 p = td->td_proc; 193 PROC_LOCK_ASSERT(p, MA_OWNED); 194 195 bzero(si, sizeof(*si)); 196 si->si_signo = sig; 197 si->si_code = code; 198 /* XXXKSE fill other fields */ 199} 200#endif 201 202/* 203 * System call to cleanup state after a signal 204 * has been taken. Reset signal mask and 205 * stack state from context left by sendsig (above). 206 * Return to previous pc as specified by 207 * context left by sendsig. 208 */ 209int 210sys_sigreturn(struct thread *td, struct sigreturn_args *uap) 211{ 212 ucontext_t uc; 213 int error; 214 215 error = copyin(uap->sigcntxp, &uc, sizeof(uc)); 216 if (error != 0) 217 return (error); 218 219 error = set_mcontext(td, &uc.uc_mcontext); 220 if (error != 0) 221 return (error); 222 223 kern_sigprocmask(td, SIG_SETMASK, &uc.uc_sigmask, NULL, 0); 224 225 return (EJUSTRETURN); 226} 227 228int 229ptrace_set_pc(struct thread *td, unsigned long addr) 230{ 231 td->td_frame->pc = (register_t) addr; 232 return 0; 233} 234 235static int 236ptrace_read_int(struct thread *td, off_t addr, int *v) 237{ 238 struct iovec iov; 239 struct uio uio; 240 241 PROC_LOCK_ASSERT(td->td_proc, MA_NOTOWNED); 242 iov.iov_base = (caddr_t) v; 243 iov.iov_len = sizeof(int); 244 uio.uio_iov = &iov; 245 uio.uio_iovcnt = 1; 246 uio.uio_offset = (off_t)addr; 247 uio.uio_resid = sizeof(int); 248 uio.uio_segflg = UIO_SYSSPACE; 249 uio.uio_rw = UIO_READ; 250 uio.uio_td = td; 251 return proc_rwmem(td->td_proc, &uio); 252} 253 254static int 255ptrace_write_int(struct thread *td, off_t addr, int v) 256{ 257 struct iovec iov; 258 struct uio uio; 259 260 PROC_LOCK_ASSERT(td->td_proc, MA_NOTOWNED); 261 iov.iov_base = (caddr_t) &v; 262 iov.iov_len = sizeof(int); 263 uio.uio_iov = &iov; 264 uio.uio_iovcnt = 1; 265 uio.uio_offset = (off_t)addr; 266 uio.uio_resid = sizeof(int); 267 uio.uio_segflg = UIO_SYSSPACE; 268 uio.uio_rw = UIO_WRITE; 269 uio.uio_td = td; 270 return proc_rwmem(td->td_proc, &uio); 271} 272 273int 274ptrace_single_step(struct thread *td) 275{ 276 unsigned va; 277 struct trapframe *locr0 = td->td_frame; 278 int i; 279 int bpinstr = MIPS_BREAK_SSTEP; 280 int curinstr; 281 struct proc *p; 282 283 p = td->td_proc; 284 PROC_UNLOCK(p); 285 /* 286 * Fetch what's at the current location. 287 */ 288 ptrace_read_int(td, (off_t)locr0->pc, &curinstr); 289 290 /* compute next address after current location */ 291 if(curinstr != 0) { 292 va = MipsEmulateBranch(locr0, locr0->pc, locr0->fsr, 293 (uintptr_t)&curinstr); 294 } else { 295 va = locr0->pc + 4; 296 } 297 if (td->td_md.md_ss_addr) { 298 printf("SS %s (%d): breakpoint already set at %x (va %x)\n", 299 p->p_comm, p->p_pid, td->td_md.md_ss_addr, va); /* XXX */ 300 return (EFAULT); 301 } 302 td->td_md.md_ss_addr = va; 303 /* 304 * Fetch what's at the current location. 305 */ 306 ptrace_read_int(td, (off_t)va, &td->td_md.md_ss_instr); 307 308 /* 309 * Store breakpoint instruction at the "next" location now. 310 */ 311 i = ptrace_write_int (td, va, bpinstr); 312 313 /* 314 * The sync'ing of I & D caches is done by procfs_domem() 315 * through procfs_rwmem(). 316 */ 317 318 PROC_LOCK(p); 319 if (i < 0) 320 return (EFAULT); 321#if 0 322 printf("SS %s (%d): breakpoint set at %x: %x (pc %x) br %x\n", 323 p->p_comm, p->p_pid, p->p_md.md_ss_addr, 324 p->p_md.md_ss_instr, locr0->pc, curinstr); /* XXX */ 325#endif 326 return (0); 327} 328 329 330void 331makectx(struct trapframe *tf, struct pcb *pcb) 332{ 333 334 pcb->pcb_regs.ra = tf->ra; 335 pcb->pcb_regs.pc = tf->pc; 336 pcb->pcb_regs.sp = tf->sp; 337} 338 339int 340fill_regs(struct thread *td, struct reg *regs) 341{ 342 memcpy(regs, td->td_frame, sizeof(struct reg)); 343 return (0); 344} 345 346int 347set_regs(struct thread *td, struct reg *regs) 348{ 349 struct trapframe *f; 350 register_t sr; 351 352 f = (struct trapframe *) td->td_frame; 353 /* 354 * Don't allow the user to change SR 355 */ 356 sr = f->sr; 357 memcpy(td->td_frame, regs, sizeof(struct reg)); 358 f->sr = sr; 359 return (0); 360} 361 362int 363get_mcontext(struct thread *td, mcontext_t *mcp, int flags) 364{ 365 struct trapframe *tp; 366 367 tp = td->td_frame; 368 PROC_LOCK(curthread->td_proc); 369 mcp->mc_onstack = sigonstack(tp->sp); 370 PROC_UNLOCK(curthread->td_proc); 371 bcopy((void *)&td->td_frame->zero, (void *)&mcp->mc_regs, 372 sizeof(mcp->mc_regs)); 373 374 mcp->mc_fpused = td->td_md.md_flags & MDTD_FPUSED; 375 if (mcp->mc_fpused) { 376 bcopy((void *)&td->td_frame->f0, (void *)&mcp->mc_fpregs, 377 sizeof(mcp->mc_fpregs)); 378 } 379 if (flags & GET_MC_CLEAR_RET) { 380 mcp->mc_regs[V0] = 0; 381 mcp->mc_regs[V1] = 0; 382 mcp->mc_regs[A3] = 0; 383 } 384 385 mcp->mc_pc = td->td_frame->pc; 386 mcp->mullo = td->td_frame->mullo; 387 mcp->mulhi = td->td_frame->mulhi; 388 mcp->mc_tls = td->td_md.md_tls; 389 return (0); 390} 391 392int 393set_mcontext(struct thread *td, mcontext_t *mcp) 394{ 395 struct trapframe *tp; 396 397 tp = td->td_frame; 398 bcopy((void *)&mcp->mc_regs, (void *)&td->td_frame->zero, 399 sizeof(mcp->mc_regs)); 400 401 td->td_md.md_flags = mcp->mc_fpused & MDTD_FPUSED; 402 if (mcp->mc_fpused) { 403 bcopy((void *)&mcp->mc_fpregs, (void *)&td->td_frame->f0, 404 sizeof(mcp->mc_fpregs)); 405 } 406 td->td_frame->pc = mcp->mc_pc; 407 td->td_frame->mullo = mcp->mullo; 408 td->td_frame->mulhi = mcp->mulhi; 409 td->td_md.md_tls = mcp->mc_tls; 410 /* Dont let user to set any bits in Status and casue registers */ 411 412 return (0); 413} 414 415int 416fill_fpregs(struct thread *td, struct fpreg *fpregs) 417{ 418 if (td == PCPU_GET(fpcurthread)) 419 MipsSaveCurFPState(td); 420 memcpy(fpregs, &td->td_frame->f0, sizeof(struct fpreg)); 421 return 0; 422} 423 424int 425set_fpregs(struct thread *td, struct fpreg *fpregs) 426{ 427 if (PCPU_GET(fpcurthread) == td) 428 PCPU_SET(fpcurthread, (struct thread *)0); 429 memcpy(&td->td_frame->f0, fpregs, sizeof(struct fpreg)); 430 return 0; 431} 432 433 434/* 435 * Clear registers on exec 436 * $sp is set to the stack pointer passed in. $pc is set to the entry 437 * point given by the exec_package passed in, as is $t9 (used for PIC 438 * code by the MIPS elf abi). 439 */ 440void 441exec_setregs(struct thread *td, struct image_params *imgp, u_long stack) 442{ 443 444 bzero((caddr_t)td->td_frame, sizeof(struct trapframe)); 445 446 /* 447 * The stack pointer has to be aligned to accommodate the largest 448 * datatype at minimum. This probably means it should be 16-byte 449 * aligned, but for now we're 8-byte aligning it. 450 */ 451 td->td_frame->sp = ((register_t) stack) & ~(sizeof(__int64_t) - 1); 452 453 /* 454 * If we're running o32 or n32 programs but have 64-bit registers, 455 * GCC may use stack-relative addressing near the top of user 456 * address space that, due to sign extension, will yield an 457 * invalid address. For instance, if sp is 0x7fffff00 then GCC 458 * might do something like this to load a word from 0x7ffffff0: 459 * 460 * addu sp, sp, 32768 461 * lw t0, -32528(sp) 462 * 463 * On systems with 64-bit registers, sp is sign-extended to 464 * 0xffffffff80007f00 and the load is instead done from 465 * 0xffffffff7ffffff0. 466 * 467 * To prevent this, we subtract 64K from the stack pointer here. 468 * 469 * For consistency, we should just always do this unless we're 470 * running n64 programs. For now, since we don't support 471 * COMPAT_FREEBSD32 on n64 kernels, we just do it unless we're 472 * running n64 kernels. 473 */ 474#if !defined(__mips_n64) 475 td->td_frame->sp -= 65536; 476#endif 477 478 td->td_frame->pc = imgp->entry_addr & ~3; 479 td->td_frame->t9 = imgp->entry_addr & ~3; /* abicall req */ 480 td->td_frame->sr = MIPS_SR_KSU_USER | MIPS_SR_EXL | MIPS_SR_INT_IE | 481 (mips_rd_status() & MIPS_SR_INT_MASK); 482#if defined(__mips_n32) 483 td->td_frame->sr |= MIPS_SR_PX; 484#elif defined(__mips_n64) 485 td->td_frame->sr |= MIPS_SR_PX | MIPS_SR_UX | MIPS_SR_KX; 486#endif 487 /* 488 * FREEBSD_DEVELOPERS_FIXME: 489 * Setup any other CPU-Specific registers (Not MIPS Standard) 490 * and/or bits in other standard MIPS registers (if CPU-Specific) 491 * that are needed. 492 */ 493 494 /* 495 * Set up arguments for the rtld-capable crt0: 496 * a0 stack pointer 497 * a1 rtld cleanup (filled in by dynamic loader) 498 * a2 rtld object (filled in by dynamic loader) 499 * a3 ps_strings 500 */ 501 td->td_frame->a0 = (register_t) stack; 502 td->td_frame->a1 = 0; 503 td->td_frame->a2 = 0; 504 td->td_frame->a3 = (register_t)imgp->ps_strings; 505 506 td->td_md.md_flags &= ~MDTD_FPUSED; 507 if (PCPU_GET(fpcurthread) == td) 508 PCPU_SET(fpcurthread, (struct thread *)0); 509 td->td_md.md_ss_addr = 0; 510} 511 512int 513ptrace_clear_single_step(struct thread *td) 514{ 515 int i; 516 struct proc *p; 517 518 p = td->td_proc; 519 PROC_LOCK_ASSERT(p, MA_OWNED); 520 if (!td->td_md.md_ss_addr) 521 return EINVAL; 522 523 /* 524 * Restore original instruction and clear BP 525 */ 526 i = ptrace_write_int (td, td->td_md.md_ss_addr, td->td_md.md_ss_instr); 527 528 /* The sync'ing of I & D caches is done by procfs_domem(). */ 529 530 if (i < 0) { 531 log(LOG_ERR, "SS %s %d: can't restore instruction at %x: %x\n", 532 p->p_comm, p->p_pid, td->td_md.md_ss_addr, 533 td->td_md.md_ss_instr); 534 } 535 td->td_md.md_ss_addr = 0; 536 return 0; 537} 538