1 /* $NetBSD: linux_machdep.c,v 1.36 2007/12/08 18:36:06 dsl Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 2000, 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Frank van der Linden and Emmanuel Dreyfus. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.36 2007/12/08 18:36:06 dsl Exp $"); 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/signalvar.h> 45 #include <sys/kernel.h> 46 #include <sys/proc.h> 47 #include <sys/user.h> 48 #include <sys/buf.h> 49 #include <sys/reboot.h> 50 #include <sys/conf.h> 51 #include <sys/exec.h> 52 #include <sys/file.h> 53 #include <sys/callout.h> 54 #include <sys/malloc.h> 55 #include <sys/mbuf.h> 56 #include <sys/msgbuf.h> 57 #include <sys/mount.h> 58 #include <sys/vnode.h> 59 #include <sys/device.h> 60 #include <sys/syscallargs.h> 61 #include <sys/filedesc.h> 62 #include <sys/exec_elf.h> 63 #include <sys/disklabel.h> 64 #include <sys/ioctl.h> 65 #include <miscfs/specfs/specdev.h> 66 67 #include <compat/linux/common/linux_types.h> 68 #include <compat/linux/common/linux_signal.h> 69 #include <compat/linux/common/linux_util.h> 70 #include <compat/linux/common/linux_ioctl.h> 71 #include <compat/linux/common/linux_hdio.h> 72 #include <compat/linux/common/linux_exec.h> 73 #include <compat/linux/common/linux_machdep.h> 74 75 #include <compat/linux/linux_syscallargs.h> 76 77 #include <sys/cpu.h> 78 #include <machine/fpu.h> 79 #include <machine/psl.h> 80 #include <machine/reg.h> 81 #include <machine/vmparam.h> 82 83 /* 84 * To see whether wscons is configured (for virtual console ioctl calls). 85 */ 86 #if defined(_KERNEL_OPT) 87 #include "wsdisplay.h" 88 #endif 89 #if (NWSDISPLAY > 0) 90 #include <dev/wscons/wsconsio.h> 91 #include <dev/wscons/wsdisplay_usl_io.h> 92 #endif 93 94 /* 95 * Set set up registers on exec. 96 * XXX not used at the moment since in sys/kern/exec_conf, LINUX_COMPAT 97 * entry uses NetBSD's native setregs instead of linux_setregs 98 */ 99 void 100 linux_setregs(struct lwp *l, struct exec_package *pack, u_long stack) 101 { 102 setregs(l, pack, stack); 103 } 104 105 /* 106 * Send an interrupt to process. 107 * 108 * Adapted from arch/powerpc/powerpc/sig_machdep.c:sendsig and 109 * compat/linux/arch/i386/linux_machdep.c:linux_sendsig 110 * 111 * XXX Does not work well yet with RT signals 112 * 113 */ 114 115 void 116 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) 117 { 118 const int sig = ksi->ksi_signo; 119 struct lwp *l = curlwp; 120 struct proc *p = l->l_proc; 121 struct trapframe *tf; 122 sig_t catcher = SIGACTION(p, sig).sa_handler; 123 struct linux_sigregs frame; 124 struct linux_pt_regs linux_regs; 125 struct linux_sigcontext sc; 126 register_t fp; 127 int onstack, error; 128 int i; 129 130 tf = trapframe(l); 131 132 /* 133 * Do we need to jump onto the signal stack? 134 */ 135 onstack = 136 (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && 137 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 138 139 /* 140 * Signal stack is broken (see at the end of linux_sigreturn), so we do 141 * not use it yet. XXX fix this. 142 */ 143 onstack=0; 144 145 /* 146 * Allocate space for the signal handler context. 147 */ 148 if (onstack) { 149 fp = (register_t) 150 ((char *)l->l_sigstk.ss_sp + 151 l->l_sigstk.ss_size); 152 } else { 153 fp = tf->fixreg[1]; 154 } 155 #ifdef DEBUG_LINUX 156 printf("fp at start of linux_sendsig = %x\n", fp); 157 #endif 158 fp -= sizeof(struct linux_sigregs); 159 fp &= ~0xf; 160 161 /* 162 * Prepare a sigcontext for later. 163 */ 164 memset(&sc, 0, sizeof sc); 165 sc.lsignal = (int)native_to_linux_signo[sig]; 166 sc.lhandler = (unsigned long)catcher; 167 native_to_linux_old_extra_sigset(&sc.lmask, &sc._unused[3], mask); 168 sc.lregs = (struct linux_pt_regs*)fp; 169 170 /* 171 * Setup the signal stack frame as Linux does it in 172 * arch/ppc/kernel/signal.c:setup_frame() 173 * 174 * Save register context. 175 */ 176 for (i = 0; i < 32; i++) 177 linux_regs.lgpr[i] = tf->fixreg[i]; 178 linux_regs.lnip = tf->srr0; 179 linux_regs.lmsr = tf->srr1 & PSL_USERSRR1; 180 linux_regs.lorig_gpr3 = tf->fixreg[3]; /* XXX Is that right? */ 181 linux_regs.lctr = tf->ctr; 182 linux_regs.llink = tf->lr; 183 linux_regs.lxer = tf->xer; 184 linux_regs.lccr = tf->cr; 185 linux_regs.lmq = 0; /* Unused, 601 only */ 186 linux_regs.ltrap = tf->exc; 187 linux_regs.ldar = tf->dar; 188 linux_regs.ldsisr = tf->dsisr; 189 linux_regs.lresult = 0; 190 191 memset(&frame, 0, sizeof(frame)); 192 memcpy(&frame.lgp_regs, &linux_regs, sizeof(linux_regs)); 193 194 save_fpu_lwp(curlwp, FPU_SAVE); 195 memcpy(&frame.lfp_regs, curpcb->pcb_fpu.fpreg, sizeof(frame.lfp_regs)); 196 197 /* 198 * Copy Linux's signal trampoline on the user stack It should not 199 * be used, but Linux binaries might expect it to be there. 200 */ 201 frame.ltramp[0] = 0x38997777; /* li r0, 0x7777 */ 202 frame.ltramp[1] = 0x44000002; /* sc */ 203 204 /* 205 * Move it to the user stack 206 * There is a little trick here, about the LINUX_ABIGAP: the 207 * linux_sigreg structure has a 56 int gap to support rs6000/xcoff 208 * binaries. But the Linux kernel seems to do without it, and it 209 * just skip it when building the stack frame. Hence the LINUX_ABIGAP. 210 */ 211 sendsig_reset(l, sig); 212 mutex_exit(&p->p_smutex); 213 error = copyout(&frame, (void *)fp, sizeof (frame) - LINUX_ABIGAP); 214 215 if (error != 0) { 216 /* 217 * Process has trashed its stack; give it an illegal 218 * instruction to halt it in its tracks. 219 */ 220 mutex_enter(&p->p_smutex); 221 sigexit(l, SIGILL); 222 /* NOTREACHED */ 223 } 224 225 /* 226 * Add a sigcontext on the stack 227 */ 228 fp -= sizeof(struct linux_sigcontext); 229 error = copyout(&sc, (void *)fp, sizeof (struct linux_sigcontext)); 230 mutex_enter(&p->p_smutex); 231 232 if (error != 0) { 233 /* 234 * Process has trashed its stack; give it an illegal 235 * instruction to halt it in its tracks. 236 */ 237 sigexit(l, SIGILL); 238 /* NOTREACHED */ 239 } 240 241 /* 242 * Set the registers according to how the Linux process expects them. 243 * "Mind the gap" Linux expects a gap here. 244 */ 245 tf->fixreg[1] = fp - LINUX__SIGNAL_FRAMESIZE; 246 tf->lr = (int)catcher; 247 tf->fixreg[3] = (int)native_to_linux_signo[sig]; 248 tf->fixreg[4] = fp; 249 tf->srr0 = (int)p->p_sigctx.ps_sigcode; 250 251 #ifdef DEBUG_LINUX 252 printf("fp at end of linux_sendsig = %x\n", fp); 253 #endif 254 /* 255 * Remember that we're now on the signal stack. 256 */ 257 if (onstack) 258 l->l_sigstk.ss_flags |= SS_ONSTACK; 259 #ifdef DEBUG_LINUX 260 printf("linux_sendsig: exitting. fp=0x%lx\n",(long)fp); 261 #endif 262 } 263 264 /* 265 * System call to cleanup state after a signal 266 * has been taken. Reset signal mask and 267 * stack state from context left by sendsig (above). 268 * Return to previous pc and psl as specified by 269 * context left by sendsig. Check carefully to 270 * make sure that the user has not modified the 271 * psl to gain improper privileges or to cause 272 * a machine fault. 273 * 274 * XXX not tested 275 */ 276 int 277 linux_sys_rt_sigreturn(struct lwp *l, void *v, register_t *retval) 278 { 279 struct linux_sys_rt_sigreturn_args /* { 280 syscallarg(struct linux_rt_sigframe *) sfp; 281 } */ *uap = v; 282 struct proc *p = l->l_proc; 283 struct linux_rt_sigframe *scp, sigframe; 284 struct linux_sigregs sregs; 285 struct linux_pt_regs *lregs; 286 struct trapframe *tf; 287 sigset_t mask; 288 int i; 289 290 /* 291 * The trampoline code hands us the context. 292 * It is unsafe to keep track of it ourselves, in the event that a 293 * program jumps out of a signal handler. 294 */ 295 scp = SCARG(uap, sfp); 296 297 /* 298 * Get the context from user stack 299 */ 300 if (copyin((void *)scp, &sigframe, sizeof(*scp))) 301 return (EFAULT); 302 303 /* 304 * Restore register context. 305 */ 306 if (copyin((void *)sigframe.luc.luc_context.lregs, 307 &sregs, sizeof(sregs))) 308 return (EFAULT); 309 lregs = (struct linux_pt_regs *)&sregs.lgp_regs; 310 311 tf = trapframe(l); 312 #ifdef DEBUG_LINUX 313 (unsigned long)tf, (unsigned long)scp); 314 #endif 315 316 if (!PSL_USEROK_P(lregs->lmsr)) 317 return (EINVAL); 318 319 for (i = 0; i < 32; i++) 320 tf->fixreg[i] = lregs->lgpr[i]; 321 tf->lr = lregs->llink; 322 tf->cr = lregs->lccr; 323 tf->xer = lregs->lxer; 324 tf->ctr = lregs->lctr; 325 tf->srr0 = lregs->lnip; 326 tf->srr1 = lregs->lmsr; 327 328 /* 329 * Make sure the fpu state is discarded 330 */ 331 save_fpu_lwp(curlwp, FPU_DISCARD); 332 333 memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs, 334 sizeof(curpcb->pcb_fpu.fpreg)); 335 336 mutex_enter(&p->p_smutex); 337 338 /* 339 * Restore signal stack. 340 * 341 * XXX cannot find the onstack information in Linux sig context. 342 * Is signal stack really supported on Linux? 343 * 344 * It seems to be supported in libc6... 345 */ 346 /* if (sc.sc_onstack & SS_ONSTACK) 347 l->l_sigstk.ss_flags |= SS_ONSTACK; 348 else */ 349 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 350 351 /* 352 * Grab the signal mask 353 */ 354 linux_to_native_sigset(&mask, &sigframe.luc.luc_sigmask); 355 (void) sigprocmask1(l, SIG_SETMASK, &mask, 0); 356 357 mutex_exit(&p->p_smutex); 358 359 return (EJUSTRETURN); 360 } 361 362 363 /* 364 * The following needs code review for potential security issues 365 */ 366 int 367 linux_sys_sigreturn(struct lwp *l, void *v, register_t *retval) 368 { 369 struct linux_sys_sigreturn_args /* { 370 syscallarg(struct linux_sigcontext *) scp; 371 } */ *uap = v; 372 struct proc *p = l->l_proc; 373 struct linux_sigcontext *scp, context; 374 struct linux_sigregs sregs; 375 struct linux_pt_regs *lregs; 376 struct trapframe *tf; 377 sigset_t mask; 378 int i; 379 380 /* 381 * The trampoline code hands us the context. 382 * It is unsafe to keep track of it ourselves, in the event that a 383 * program jumps out of a signal handler. 384 */ 385 scp = SCARG(uap, scp); 386 387 /* 388 * Get the context from user stack 389 */ 390 if (copyin(scp, &context, sizeof(*scp))) 391 return (EFAULT); 392 393 /* 394 * Restore register context. 395 */ 396 if (copyin((void *)context.lregs, &sregs, sizeof(sregs))) 397 return (EFAULT); 398 lregs = (struct linux_pt_regs *)&sregs.lgp_regs; 399 400 tf = trapframe(l); 401 #ifdef DEBUG_LINUX 402 printf("linux_sys_sigreturn: trapframe=0x%lx scp=0x%lx\n", 403 (unsigned long)tf, (unsigned long)scp); 404 #endif 405 406 if (!PSL_USEROK_P(lregs->lmsr)) 407 return (EINVAL); 408 409 for (i = 0; i < 32; i++) 410 tf->fixreg[i] = lregs->lgpr[i]; 411 tf->lr = lregs->llink; 412 tf->cr = lregs->lccr; 413 tf->xer = lregs->lxer; 414 tf->ctr = lregs->lctr; 415 tf->srr0 = lregs->lnip; 416 tf->srr1 = lregs->lmsr; 417 418 /* 419 * Make sure the fpu state is discarded 420 */ 421 save_fpu_lwp(curlwp, FPU_DISCARD); 422 423 memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs, 424 sizeof(curpcb->pcb_fpu.fpreg)); 425 426 mutex_enter(&p->p_smutex); 427 428 /* 429 * Restore signal stack. 430 * 431 * XXX cannot find the onstack information in Linux sig context. 432 * Is signal stack really supported on Linux? 433 */ 434 #if 0 435 if (sc.sc_onstack & SS_ONSTACK) 436 l->l_sigstk.ss_flags |= SS_ONSTACK; 437 else 438 #endif 439 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 440 441 /* Restore signal mask. */ 442 linux_old_extra_to_native_sigset(&mask, &context.lmask, 443 &context._unused[3]); 444 (void) sigprocmask1(l, SIG_SETMASK, &mask, 0); 445 446 mutex_exit(&p->p_smutex); 447 448 return (EJUSTRETURN); 449 } 450 451 452 #if 0 453 int 454 linux_sys_modify_ldt(struct proc *p, void *v, register_t *retval) 455 { 456 /* 457 * This syscall is not implemented in Linux/PowerPC: we should not 458 * be here 459 */ 460 #ifdef DEBUG_LINUX 461 printf("linux_sys_modify_ldt: should not be here.\n"); 462 #endif 463 return 0; 464 } 465 #endif 466 467 /* 468 * major device numbers remapping 469 */ 470 dev_t 471 linux_fakedev(dev_t dev, int raw) 472 { 473 /* XXX write me */ 474 return dev; 475 } 476 477 /* 478 * We come here in a last attempt to satisfy a Linux ioctl() call 479 */ 480 int 481 linux_machdepioctl(struct lwp *l, void *v, register_t *retval) 482 { 483 struct linux_sys_ioctl_args /* { 484 syscallarg(int) fd; 485 syscallarg(u_long) com; 486 syscallarg(void *) data; 487 } */ *uap = v; 488 struct sys_ioctl_args bia; 489 u_long com; 490 491 SCARG(&bia, fd) = SCARG(uap, fd); 492 SCARG(&bia, data) = SCARG(uap, data); 493 com = SCARG(uap, com); 494 495 switch (com) { 496 default: 497 printf("linux_machdepioctl: invalid ioctl %08lx\n", com); 498 return EINVAL; 499 } 500 SCARG(&bia, com) = com; 501 /* XXX NJWLWP */ 502 return sys_ioctl(curlwp, &bia, retval); 503 } 504 #if 0 505 /* 506 * Set I/O permissions for a process. Just set the maximum level 507 * right away (ignoring the argument), otherwise we would have 508 * to rely on I/O permission maps, which are not implemented. 509 */ 510 int 511 linux_sys_iopl(struct lwp *l, void *v, register_t *retval) 512 { 513 /* 514 * This syscall is not implemented in Linux/PowerPC: we should not be here 515 */ 516 #ifdef DEBUG_LINUX 517 printf("linux_sys_iopl: should not be here.\n"); 518 #endif 519 return 0; 520 } 521 #endif 522 523 /* 524 * See above. If a root process tries to set access to an I/O port, 525 * just let it have the whole range. 526 */ 527 int 528 linux_sys_ioperm(struct lwp *l, void *v, register_t *retval) 529 { 530 /* 531 * This syscall is not implemented in Linux/PowerPC: we should not be here 532 */ 533 #ifdef DEBUG_LINUX 534 printf("linux_sys_ioperm: should not be here.\n"); 535 #endif 536 return 0; 537 } 538 539 /* 540 * wrapper linux_sys_new_uname() -> linux_sys_uname() 541 */ 542 int 543 linux_sys_new_uname(struct lwp *l, void *v, register_t *retval) 544 { 545 return linux_sys_uname(l, v, retval); 546 } 547 548 /* 549 * wrapper linux_sys_new_select() -> linux_sys_select() 550 */ 551 int 552 linux_sys_new_select(struct lwp *l, void *v, register_t *retval) 553 { 554 return linux_sys_select(l, v, retval); 555 } 556 557 int 558 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg) 559 { 560 return 0; 561 } 562