linux_machdep.c revision 1.22
1 /* $NetBSD: linux_machdep.c,v 1.22 2007/05/21 15:35:47 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2005 Emmanuel Dreyfus, all rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Emmanuel Dreyfus 17 * 4. The name of the author may not be used to endorse or promote 18 * products derived from this software without specific prior written 19 * permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE THE AUTHOR AND CONTRIBUTORS ``AS IS'' 22 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, 23 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 24 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS 25 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 26 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 27 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 29 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 30 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 31 * POSSIBILITY OF SUCH DAMAGE. 32 */ 33 34 #include <sys/cdefs.h> 35 36 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.22 2007/05/21 15:35:47 christos Exp $"); 37 38 #include <sys/param.h> 39 #include <sys/types.h> 40 #include <sys/systm.h> 41 #include <sys/signal.h> 42 #include <sys/exec.h> 43 #include <sys/proc.h> 44 #include <sys/ptrace.h> /* for process_read_fpregs() */ 45 #include <sys/user.h> 46 #include <sys/wait.h> 47 #include <sys/ucontext.h> 48 #include <sys/conf.h> 49 50 #include <machine/reg.h> 51 #include <machine/pcb.h> 52 #include <machine/fpu.h> 53 #include <machine/mcontext.h> 54 #include <machine/specialreg.h> 55 #include <machine/vmparam.h> 56 57 /* 58 * To see whether wscons is configured (for virtual console ioctl calls). 59 */ 60 #if defined(_KERNEL_OPT) 61 #include "wsdisplay.h" 62 #endif 63 #if (NWSDISPLAY > 0) 64 #include <dev/wscons/wsconsio.h> 65 #include <dev/wscons/wsdisplay_usl_io.h> 66 #endif 67 68 69 #include <compat/linux/common/linux_signal.h> 70 #include <compat/linux/common/linux_errno.h> 71 #include <compat/linux/common/linux_exec.h> 72 #include <compat/linux/common/linux_ioctl.h> 73 #include <compat/linux/common/linux_prctl.h> 74 #include <compat/linux/common/linux_machdep.h> 75 #include <compat/linux/linux_syscall.h> 76 #include <compat/linux/linux_syscallargs.h> 77 78 static void linux_buildcontext(struct lwp *, void *, void *); 79 80 void 81 linux_setregs(l, epp, stack) 82 struct lwp *l; 83 struct exec_package *epp; 84 u_long stack; 85 { 86 struct pcb *pcb = &l->l_addr->u_pcb; 87 struct trapframe *tf; 88 89 /* If we were using the FPU, forget about it. */ 90 if (l->l_addr->u_pcb.pcb_fpcpu != NULL) 91 fpusave_lwp(l, 0); 92 93 l->l_md.md_flags &= ~MDP_USEDFPU; 94 pcb->pcb_flags = 0; 95 pcb->pcb_savefpu.fp_fxsave.fx_fcw = __NetBSD_NPXCW__; 96 pcb->pcb_savefpu.fp_fxsave.fx_mxcsr = __INITIAL_MXCSR__; 97 pcb->pcb_savefpu.fp_fxsave.fx_mxcsr_mask = __INITIAL_MXCSR_MASK__; 98 pcb->pcb_fs = 0; 99 pcb->pcb_gs = 0; 100 101 l->l_proc->p_flag &= ~PK_32; 102 103 tf = l->l_md.md_regs; 104 tf->tf_rax = 0; 105 tf->tf_rbx = 0; 106 tf->tf_rcx = epp->ep_entry; 107 tf->tf_rdx = 0; 108 tf->tf_rsi = 0; 109 tf->tf_rdi = 0; 110 tf->tf_rbp = 0; 111 tf->tf_rsp = stack; 112 tf->tf_r8 = 0; 113 tf->tf_r9 = 0; 114 tf->tf_r10 = 0; 115 tf->tf_r11 = 0; 116 tf->tf_r12 = 0; 117 tf->tf_r13 = 0; 118 tf->tf_r14 = 0; 119 tf->tf_r15 = 0; 120 tf->tf_rip = epp->ep_entry; 121 tf->tf_rflags = PSL_USERSET; 122 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 123 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 124 tf->tf_ds = 0; 125 tf->tf_es = 0; 126 tf->tf_fs = 0; 127 tf->tf_gs = 0; 128 129 return; 130 } 131 132 void 133 linux_sendsig(ksi, mask) 134 const ksiginfo_t *ksi; 135 const sigset_t *mask; 136 { 137 struct lwp *l = curlwp; 138 struct proc *p = l->l_proc; 139 struct sigacts *ps = p->p_sigacts; 140 int onstack, error; 141 int sig = ksi->ksi_signo; 142 struct linux_rt_sigframe *sfp, sigframe; 143 struct linux__fpstate *fpsp, fpstate; 144 struct fpreg fpregs; 145 struct trapframe *tf = l->l_md.md_regs; 146 sig_t catcher = SIGACTION(p, sig).sa_handler; 147 linux_sigset_t lmask; 148 char *sp; 149 150 /* Do we need to jump onto the signal stack? */ 151 onstack = 152 (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && 153 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 154 155 /* Allocate space for the signal handler context. */ 156 if (onstack) 157 sp = ((char *)l->l_sigstk.ss_sp + 158 l->l_sigstk.ss_size); 159 else 160 sp = (char *)tf->tf_rsp - 128; 161 162 /* 163 * Save FPU state, if any 164 */ 165 if (l->l_md.md_flags & MDP_USEDFPU) { 166 sp = (char *) 167 (((long)sp - sizeof(struct linux__fpstate)) & ~0xfUL); 168 fpsp = (struct linux__fpstate *)sp; 169 } else 170 fpsp = NULL; 171 172 /* 173 * Populate the rt_sigframe 174 */ 175 sp = (char *) 176 ((((long)sp - sizeof(struct linux_rt_sigframe)) & ~0xfUL) - 8); 177 sfp = (struct linux_rt_sigframe *)sp; 178 179 bzero(&sigframe, sizeof(sigframe)); 180 if (ps->sa_sigdesc[sig].sd_vers != 0) 181 sigframe.pretcode = 182 (char *)(u_long)ps->sa_sigdesc[sig].sd_tramp; 183 else 184 sigframe.pretcode = NULL; 185 186 /* 187 * The user context 188 */ 189 sigframe.uc.luc_flags = 0; 190 sigframe.uc.luc_link = NULL; 191 192 /* This is used regardless of SA_ONSTACK in Linux */ 193 sigframe.uc.luc_stack.ss_sp = l->l_sigstk.ss_sp; 194 sigframe.uc.luc_stack.ss_size = l->l_sigstk.ss_size; 195 sigframe.uc.luc_stack.ss_flags = 0; 196 if (l->l_sigstk.ss_flags & SS_ONSTACK) 197 sigframe.uc.luc_stack.ss_flags |= LINUX_SS_ONSTACK; 198 if (l->l_sigstk.ss_flags & SS_DISABLE) 199 sigframe.uc.luc_stack.ss_flags |= LINUX_SS_DISABLE; 200 201 sigframe.uc.luc_mcontext.r8 = tf->tf_r8; 202 sigframe.uc.luc_mcontext.r9 = tf->tf_r9; 203 sigframe.uc.luc_mcontext.r10 = tf->tf_r10; 204 sigframe.uc.luc_mcontext.r11 = tf->tf_r11; 205 sigframe.uc.luc_mcontext.r12 = tf->tf_r12; 206 sigframe.uc.luc_mcontext.r13 = tf->tf_r13; 207 sigframe.uc.luc_mcontext.r14 = tf->tf_r14; 208 sigframe.uc.luc_mcontext.r15 = tf->tf_r15; 209 sigframe.uc.luc_mcontext.rdi = tf->tf_rdi; 210 sigframe.uc.luc_mcontext.rsi = tf->tf_rsi; 211 sigframe.uc.luc_mcontext.rbp = tf->tf_rbp; 212 sigframe.uc.luc_mcontext.rbx = tf->tf_rbx; 213 sigframe.uc.luc_mcontext.rdx = tf->tf_rdx; 214 sigframe.uc.luc_mcontext.rcx = tf->tf_rcx; 215 sigframe.uc.luc_mcontext.rsp = tf->tf_rsp; 216 sigframe.uc.luc_mcontext.rip = tf->tf_rip; 217 sigframe.uc.luc_mcontext.eflags = tf->tf_rflags; 218 sigframe.uc.luc_mcontext.cs = tf->tf_cs; 219 sigframe.uc.luc_mcontext.gs = tf->tf_gs; 220 sigframe.uc.luc_mcontext.fs = tf->tf_fs; 221 sigframe.uc.luc_mcontext.err = tf->tf_err; 222 sigframe.uc.luc_mcontext.trapno = tf->tf_trapno; 223 native_to_linux_sigset(&lmask, mask); 224 sigframe.uc.luc_mcontext.oldmask = lmask.sig[0]; 225 sigframe.uc.luc_mcontext.cr2 = (long)l->l_addr->u_pcb.pcb_onfault; 226 sigframe.uc.luc_mcontext.fpstate = fpsp; 227 native_to_linux_sigset(&sigframe.uc.luc_sigmask, mask); 228 229 /* 230 * the siginfo structure 231 */ 232 sigframe.info.lsi_signo = native_to_linux_signo[sig]; 233 sigframe.info.lsi_errno = native_to_linux_errno[ksi->ksi_errno]; 234 sigframe.info.lsi_code = ksi->ksi_code; 235 236 /* XXX This is a rought conversion, taken from i386 code */ 237 switch (sigframe.info.lsi_signo) { 238 case LINUX_SIGILL: 239 case LINUX_SIGFPE: 240 case LINUX_SIGSEGV: 241 case LINUX_SIGBUS: 242 case LINUX_SIGTRAP: 243 sigframe.info._sifields._sigfault._addr = ksi->ksi_addr; 244 break; 245 case LINUX_SIGCHLD: 246 sigframe.info._sifields._sigchld._pid = ksi->ksi_pid; 247 sigframe.info._sifields._sigchld._uid = ksi->ksi_uid; 248 sigframe.info._sifields._sigchld._utime = ksi->ksi_utime; 249 sigframe.info._sifields._sigchld._stime = ksi->ksi_stime; 250 251 if (WCOREDUMP(ksi->ksi_status)) { 252 sigframe.info.lsi_code = LINUX_CLD_DUMPED; 253 sigframe.info._sifields._sigchld._status = 254 _WSTATUS(ksi->ksi_status); 255 } else if (_WSTATUS(ksi->ksi_status)) { 256 sigframe.info.lsi_code = LINUX_CLD_KILLED; 257 sigframe.info._sifields._sigchld._status = 258 _WSTATUS(ksi->ksi_status); 259 } else { 260 sigframe.info.lsi_code = LINUX_CLD_EXITED; 261 sigframe.info._sifields._sigchld._status = 262 ((ksi->ksi_status & 0xff00U) >> 8); 263 } 264 break; 265 case LINUX_SIGIO: 266 sigframe.info._sifields._sigpoll._band = ksi->ksi_band; 267 sigframe.info._sifields._sigpoll._fd = ksi->ksi_fd; 268 break; 269 default: 270 sigframe.info._sifields._sigchld._pid = ksi->ksi_pid; 271 sigframe.info._sifields._sigchld._uid = ksi->ksi_uid; 272 if ((sigframe.info.lsi_signo == LINUX_SIGALRM) || 273 (sigframe.info.lsi_signo >= LINUX_SIGRTMIN)) 274 sigframe.info._sifields._timer._sigval.sival_ptr = 275 ksi->ksi_value.sival_ptr; 276 break; 277 } 278 279 sendsig_reset(l, sig); 280 mutex_exit(&p->p_smutex); 281 error = 0; 282 283 /* 284 * Save FPU state, if any 285 */ 286 if (fpsp != NULL) { 287 (void)process_read_fpregs(l, &fpregs); 288 bzero(&fpstate, sizeof(fpstate)); 289 fpstate.cwd = fpregs.fp_fcw; 290 fpstate.swd = fpregs.fp_fsw; 291 fpstate.twd = fpregs.fp_ftw; 292 fpstate.fop = fpregs.fp_fop; 293 fpstate.rip = fpregs.fp_rip; 294 fpstate.rdp = fpregs.fp_rdp; 295 fpstate.mxcsr = fpregs.fp_mxcsr; 296 fpstate.mxcsr_mask = fpregs.fp_mxcsr_mask; 297 memcpy(&fpstate.st_space, &fpregs.fp_st, 298 sizeof(fpstate.st_space)); 299 memcpy(&fpstate.xmm_space, &fpregs.fp_xmm, 300 sizeof(fpstate.xmm_space)); 301 error = copyout(&fpstate, fpsp, sizeof(fpstate)); 302 } 303 304 if (error == 0) 305 error = copyout(&sigframe, sp, sizeof(sigframe)); 306 307 mutex_enter(&p->p_smutex); 308 309 if (error != 0) { 310 sigexit(l, SIGILL); 311 return; 312 } 313 314 linux_buildcontext(l, catcher, sp); 315 tf->tf_rdi = sigframe.info.lsi_signo; 316 tf->tf_rax = 0; 317 tf->tf_rsi = (long)&sfp->info; 318 tf->tf_rdx = (long)&sfp->uc; 319 320 /* 321 * Remember we use signal stack 322 */ 323 if (onstack) 324 l->l_sigstk.ss_flags |= SS_ONSTACK; 325 return; 326 } 327 328 int 329 linux_sys_modify_ldt(l, v, retval) 330 struct lwp *l; 331 void *v; 332 register_t *retval; 333 { 334 printf("linux_sys_modify_ldt\n"); 335 return 0; 336 } 337 338 int 339 linux_sys_iopl(l, v, retval) 340 struct lwp *l; 341 void *v; 342 register_t *retval; 343 { 344 return 0; 345 } 346 347 int 348 linux_sys_ioperm(l, v, retval) 349 struct lwp *l; 350 void *v; 351 register_t *retval; 352 { 353 return 0; 354 } 355 356 dev_t 357 linux_fakedev(dev, raw) 358 dev_t dev; 359 int raw; 360 { 361 362 extern const struct cdevsw ptc_cdevsw, pts_cdevsw; 363 const struct cdevsw *cd = cdevsw_lookup(dev); 364 365 if (raw) { 366 #if (NWSDISPLAY > 0) 367 extern const struct cdevsw wsdisplay_cdevsw; 368 if (cd == &wsdisplay_cdevsw) 369 return makedev(LINUX_CONS_MAJOR, (minor(dev) + 1)); 370 #endif 371 } 372 373 if (cd == &ptc_cdevsw) 374 return makedev(LINUX_PTC_MAJOR, minor(dev)); 375 if (cd == &pts_cdevsw) 376 return makedev(LINUX_PTS_MAJOR, minor(dev)); 377 378 return ((minor(dev) & 0xff) | ((major(dev) & 0xfff) << 8) 379 | (((unsigned long long int) (minor(dev) & ~0xff)) << 12) 380 | (((unsigned long long int) (major(dev) & ~0xfff)) << 32)); 381 } 382 383 int 384 linux_machdepioctl(l, v, retval) 385 struct lwp *l; 386 void *v; 387 register_t *retval; 388 { 389 return 0; 390 } 391 392 int 393 linux_sys_rt_sigreturn(l, v, retval) 394 struct lwp *l; 395 void *v; 396 register_t *retval; 397 { 398 struct linux_ucontext *luctx; 399 struct trapframe *tf = l->l_md.md_regs; 400 struct linux_sigcontext *lsigctx; 401 struct linux__fpstate fpstate; 402 struct linux_rt_sigframe frame, *fp; 403 ucontext_t uctx; 404 mcontext_t *mctx; 405 struct fxsave64 *fxsave; 406 int error; 407 408 fp = (struct linux_rt_sigframe *)(tf->tf_rsp - 8); 409 if ((error = copyin(fp, &frame, sizeof(frame))) != 0) { 410 mutex_enter(&l->l_proc->p_smutex); 411 sigexit(l, SIGILL); 412 return error; 413 } 414 luctx = &frame.uc; 415 lsigctx = &luctx->luc_mcontext; 416 417 bzero(&uctx, sizeof(uctx)); 418 mctx = (mcontext_t *)&uctx.uc_mcontext; 419 fxsave = (struct fxsave64 *)&mctx->__fpregs; 420 421 /* 422 * Set the flags. Linux always have CPU, stack and signal state, 423 * FPU is optional. uc_flags is not used to tell what we have. 424 */ 425 uctx.uc_flags = (_UC_SIGMASK|_UC_CPU|_UC_STACK|_UC_CLRSTACK); 426 if (lsigctx->fpstate != NULL) 427 uctx.uc_flags |= _UC_FPU; 428 uctx.uc_link = NULL; 429 430 /* 431 * Signal set 432 */ 433 linux_to_native_sigset(&uctx.uc_sigmask, &luctx->luc_sigmask); 434 435 /* 436 * CPU state 437 */ 438 mctx->__gregs[_REG_R8] = lsigctx->r8; 439 mctx->__gregs[_REG_R9] = lsigctx->r9; 440 mctx->__gregs[_REG_R10] = lsigctx->r10; 441 mctx->__gregs[_REG_R11] = lsigctx->r11; 442 mctx->__gregs[_REG_R12] = lsigctx->r12; 443 mctx->__gregs[_REG_R13] = lsigctx->r13; 444 mctx->__gregs[_REG_R14] = lsigctx->r14; 445 mctx->__gregs[_REG_R15] = lsigctx->r15; 446 mctx->__gregs[_REG_RDI] = lsigctx->rdi; 447 mctx->__gregs[_REG_RSI] = lsigctx->rsi; 448 mctx->__gregs[_REG_RBP] = lsigctx->rbp; 449 mctx->__gregs[_REG_RBX] = lsigctx->rbx; 450 mctx->__gregs[_REG_RAX] = tf->tf_rax; 451 mctx->__gregs[_REG_RDX] = lsigctx->rdx; 452 mctx->__gregs[_REG_RCX] = lsigctx->rcx; 453 mctx->__gregs[_REG_RIP] = lsigctx->rip; 454 mctx->__gregs[_REG_RFL] = lsigctx->eflags; 455 mctx->__gregs[_REG_CS] = lsigctx->cs; 456 mctx->__gregs[_REG_GS] = lsigctx->gs; 457 mctx->__gregs[_REG_FS] = lsigctx->fs; 458 mctx->__gregs[_REG_ERR] = lsigctx->err; 459 mctx->__gregs[_REG_TRAPNO] = lsigctx->trapno; 460 mctx->__gregs[_REG_ES] = tf->tf_es; 461 mctx->__gregs[_REG_DS] = tf->tf_ds; 462 mctx->__gregs[_REG_URSP] = lsigctx->rsp; /* XXX */ 463 mctx->__gregs[_REG_SS] = tf->tf_ss; 464 465 /* 466 * FPU state 467 */ 468 if (lsigctx->fpstate != NULL) { 469 error = copyin(lsigctx->fpstate, &fpstate, sizeof(fpstate)); 470 if (error != 0) { 471 mutex_enter(&l->l_proc->p_smutex); 472 sigexit(l, SIGILL); 473 return error; 474 } 475 476 fxsave->fx_fcw = fpstate.cwd; 477 fxsave->fx_fsw = fpstate.swd; 478 fxsave->fx_ftw = fpstate.twd; 479 fxsave->fx_fop = fpstate.fop; 480 fxsave->fx_rip = fpstate.rip; 481 fxsave->fx_rdp = fpstate.rdp; 482 fxsave->fx_mxcsr = fpstate.mxcsr; 483 fxsave->fx_mxcsr_mask = fpstate.mxcsr_mask; 484 memcpy(&fxsave->fx_st, &fpstate.st_space, 485 sizeof(fxsave->fx_st)); 486 memcpy(&fxsave->fx_xmm, &fpstate.xmm_space, 487 sizeof(fxsave->fx_xmm)); 488 } 489 490 /* 491 * And the stack 492 */ 493 uctx.uc_stack.ss_flags = 0; 494 if (luctx->luc_stack.ss_flags & LINUX_SS_ONSTACK); 495 uctx.uc_stack.ss_flags = SS_ONSTACK; 496 497 if (luctx->luc_stack.ss_flags & LINUX_SS_DISABLE); 498 uctx.uc_stack.ss_flags = SS_DISABLE; 499 500 uctx.uc_stack.ss_sp = luctx->luc_stack.ss_sp; 501 uctx.uc_stack.ss_size = luctx->luc_stack.ss_size; 502 503 /* 504 * And let setucontext deal with that. 505 */ 506 mutex_enter(&l->l_proc->p_smutex); 507 error = setucontext(l, &uctx); 508 mutex_exit(&l->l_proc->p_smutex); 509 510 return error; 511 } 512 513 int 514 linux_sys_arch_prctl(l, v, retval) 515 struct lwp *l; 516 void *v; 517 register_t *retval; 518 { 519 struct linux_sys_arch_prctl_args /* { 520 syscallarg(int) code; 521 syscallarg(unsigned long) addr; 522 } */ *uap = v; 523 struct pcb *pcb = &l->l_addr->u_pcb; 524 struct trapframe *tf = l->l_md.md_regs; 525 int error; 526 uint64_t taddr; 527 528 switch(SCARG(uap, code)) { 529 case LINUX_ARCH_SET_GS: 530 taddr = SCARG(uap, addr); 531 if (taddr >= VM_MAXUSER_ADDRESS) 532 return EINVAL; 533 pcb->pcb_gs = taddr; 534 pcb->pcb_flags |= PCB_GS64; 535 if (l == curlwp) 536 wrmsr(MSR_KERNELGSBASE, taddr); 537 break; 538 539 case LINUX_ARCH_GET_GS: 540 if (pcb->pcb_flags & PCB_GS64) 541 taddr = pcb->pcb_gs; 542 else { 543 error = memseg_baseaddr(l, tf->tf_fs, NULL, 0, &taddr); 544 if (error != 0) 545 return error; 546 } 547 error = copyout(&taddr, (char *)SCARG(uap, addr), 8); 548 if (error != 0) 549 return error; 550 break; 551 552 case LINUX_ARCH_SET_FS: 553 taddr = SCARG(uap, addr); 554 if (taddr >= VM_MAXUSER_ADDRESS) 555 return EINVAL; 556 pcb->pcb_fs = taddr; 557 pcb->pcb_flags |= PCB_FS64; 558 if (l == curlwp) 559 wrmsr(MSR_FSBASE, taddr); 560 break; 561 562 case LINUX_ARCH_GET_FS: 563 if (pcb->pcb_flags & PCB_FS64) 564 taddr = pcb->pcb_fs; 565 else { 566 error = memseg_baseaddr(l, tf->tf_fs, NULL, 0, &taddr); 567 if (error != 0) 568 return error; 569 } 570 error = copyout(&taddr, (char *)SCARG(uap, addr), 8); 571 if (error != 0) 572 return error; 573 break; 574 575 default: 576 #ifdef DEBUG_LINUX 577 printf("linux_sys_arch_prctl: unexpected code %d\n", 578 SCARG(uap, code)); 579 #endif 580 return EINVAL; 581 } 582 583 return 0; 584 } 585 586 const int linux_vsyscall_to_syscall[] = { 587 LINUX_SYS_gettimeofday, 588 LINUX_SYS_time, 589 LINUX_SYS_nosys, 590 LINUX_SYS_nosys, 591 }; 592 593 int 594 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg) 595 { 596 struct trapframe *tf = arg; 597 uint64_t retaddr; 598 int vsyscallnr; 599 600 /* 601 * Check for a vsyscall. %rip must be the fault address, 602 * and the address must be in the Linux vsyscall area. 603 * Also, vsyscalls are only done at 1024-byte boundaries. 604 */ 605 606 if (__predict_true(trapaddr < LINUX_VSYSCALL_START)) 607 return 0; 608 609 if (trapaddr != tf->tf_rip) 610 return 0; 611 612 if ((tf->tf_rip & (LINUX_VSYSCALL_SIZE - 1)) != 0) 613 return 0; 614 615 vsyscallnr = (tf->tf_rip - LINUX_VSYSCALL_START) / LINUX_VSYSCALL_SIZE; 616 617 if (vsyscallnr > LINUX_VSYSCALL_MAXNR) 618 return 0; 619 620 /* 621 * Get the return address from the top of the stack, 622 * and fix up the return address. 623 * This assumes the faulting instruction was callq *reg, 624 * which is the only way that vsyscalls are ever entered. 625 */ 626 if (copyin((void *)tf->tf_rsp, &retaddr, sizeof retaddr) != 0) 627 return 0; 628 tf->tf_rip = retaddr; 629 tf->tf_rax = linux_vsyscall_to_syscall[vsyscallnr]; 630 tf->tf_rsp += 8; /* "pop" the return address */ 631 632 #if 0 633 printf("usertrap: rip %p rsp %p retaddr %p vsys %d sys %d\n", 634 (void *)tf->tf_rip, (void *)tf->tf_rsp, (void *)retaddr, 635 vsyscallnr, (int)tf->tf_rax); 636 #endif 637 638 (*l->l_proc->p_md.md_syscall)(tf); 639 640 return 1; 641 } 642 643 static void 644 linux_buildcontext(struct lwp *l, void *catcher, void *f) 645 { 646 struct trapframe *tf = l->l_md.md_regs; 647 648 tf->tf_ds = GSEL(GUDATA_SEL, SEL_UPL); 649 tf->tf_rip = (u_int64_t)catcher; 650 tf->tf_cs = GSEL(GUCODE_SEL, SEL_UPL); 651 tf->tf_rflags &= ~(PSL_T|PSL_VM|PSL_AC); 652 tf->tf_rsp = (u_int64_t)f; 653 tf->tf_ss = GSEL(GUDATA_SEL, SEL_UPL); 654 } 655 656 void * 657 linux_get_newtls(l) 658 struct lwp *l; 659 { 660 struct trapframe *tf = l->l_md.md_regs; 661 662 return (void *)tf->tf_r8; 663 } 664 665 int 666 linux_set_newtls(l, tls) 667 struct lwp *l; 668 void *tls; 669 { 670 struct linux_sys_arch_prctl_args cup; 671 register_t retval; 672 673 SCARG(&cup, code) = LINUX_ARCH_SET_FS; 674 SCARG(&cup, addr) = (unsigned long)tls; 675 676 return linux_sys_arch_prctl(l, &cup, &retval); 677 } 678
Indexes created Tue Sep 30 20:09:53 GMT 2025