1 /* $NetBSD: linux_machdep.c,v 1.45 2011/01/20 11:59:24 he 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.45 2011/01/20 11:59:24 he Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/signalvar.h> 38 #include <sys/kernel.h> 39 #include <sys/proc.h> 40 #include <sys/buf.h> 41 #include <sys/reboot.h> 42 #include <sys/conf.h> 43 #include <sys/exec.h> 44 #include <sys/file.h> 45 #include <sys/callout.h> 46 #include <sys/malloc.h> 47 #include <sys/mbuf.h> 48 #include <sys/msgbuf.h> 49 #include <sys/mount.h> 50 #include <sys/vnode.h> 51 #include <sys/device.h> 52 #include <sys/syscallargs.h> 53 #include <sys/filedesc.h> 54 #include <sys/exec_elf.h> 55 #include <sys/disklabel.h> 56 #include <sys/ioctl.h> 57 #include <miscfs/specfs/specdev.h> 58 59 #include <compat/linux/common/linux_types.h> 60 #include <compat/linux/common/linux_signal.h> 61 #include <compat/linux/common/linux_util.h> 62 #include <compat/linux/common/linux_ioctl.h> 63 #include <compat/linux/common/linux_hdio.h> 64 #include <compat/linux/common/linux_exec.h> 65 #include <compat/linux/common/linux_machdep.h> 66 67 #include <compat/linux/linux_syscallargs.h> 68 69 #include <sys/cpu.h> 70 #include <machine/fpu.h> 71 #include <machine/psl.h> 72 #include <machine/pcb.h> 73 #include <machine/vmparam.h> 74 75 /* 76 * To see whether wscons is configured (for virtual console ioctl calls). 77 */ 78 #if defined(_KERNEL_OPT) 79 #include "wsdisplay.h" 80 #endif 81 #if (NWSDISPLAY > 0) 82 #include <dev/wscons/wsconsio.h> 83 #include <dev/wscons/wsdisplay_usl_io.h> 84 #endif 85 86 /* 87 * Set set up registers on exec. 88 */ 89 void 90 linux_setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack) 91 { 92 setregs(l, pack, stack); 93 } 94 95 /* 96 * Send an interrupt to process. 97 * 98 * Adapted from arch/powerpc/powerpc/sig_machdep.c:sendsig and 99 * compat/linux/arch/i386/linux_machdep.c:linux_sendsig 100 * 101 * XXX Does not work well yet with RT signals 102 * 103 */ 104 105 void 106 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) 107 { 108 const int sig = ksi->ksi_signo; 109 struct lwp *l = curlwp; 110 struct proc *p = l->l_proc; 111 struct trapframe *tf; 112 sig_t catcher = SIGACTION(p, sig).sa_handler; 113 struct linux_sigregs frame; 114 struct linux_pt_regs linux_regs; 115 struct linux_sigcontext sc; 116 register_t fp; 117 int onstack, error; 118 int i; 119 120 tf = trapframe(l); 121 122 /* 123 * Do we need to jump onto the signal stack? 124 */ 125 onstack = 126 (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && 127 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 128 129 /* 130 * Signal stack is broken (see at the end of linux_sigreturn), so we do 131 * not use it yet. XXX fix this. 132 */ 133 onstack=0; 134 135 /* 136 * Allocate space for the signal handler context. 137 */ 138 if (onstack) { 139 fp = (register_t) 140 ((char *)l->l_sigstk.ss_sp + 141 l->l_sigstk.ss_size); 142 } else { 143 fp = tf->tf_fixreg[1]; 144 } 145 #ifdef DEBUG_LINUX 146 printf("fp at start of linux_sendsig = %x\n", fp); 147 #endif 148 fp -= sizeof(struct linux_sigregs); 149 fp &= ~0xf; 150 151 /* 152 * Prepare a sigcontext for later. 153 */ 154 memset(&sc, 0, sizeof sc); 155 sc.lsignal = (int)native_to_linux_signo[sig]; 156 sc.lhandler = (unsigned long)catcher; 157 native_to_linux_old_extra_sigset(&sc.lmask, &sc._unused[3], mask); 158 sc.lregs = (struct linux_pt_regs*)fp; 159 160 /* 161 * Setup the signal stack frame as Linux does it in 162 * arch/ppc/kernel/signal.c:setup_frame() 163 * 164 * Save register context. 165 */ 166 for (i = 0; i < 32; i++) 167 linux_regs.lgpr[i] = tf->tf_fixreg[i]; 168 linux_regs.lnip = tf->tf_srr0; 169 linux_regs.lmsr = tf->tf_srr1 & PSL_USERSRR1; 170 linux_regs.lorig_gpr3 = tf->tf_fixreg[3]; /* XXX Is that right? */ 171 linux_regs.lctr = tf->tf_ctr; 172 linux_regs.llink = tf->tf_lr; 173 linux_regs.lxer = tf->tf_xer; 174 linux_regs.lccr = tf->tf_cr; 175 linux_regs.lmq = 0; /* Unused, 601 only */ 176 linux_regs.ltrap = tf->tf_exc; 177 linux_regs.ldar = tf->tf_dar; 178 linux_regs.ldsisr = tf->tf_dsisr; 179 linux_regs.lresult = 0; 180 181 memset(&frame, 0, sizeof(frame)); 182 memcpy(&frame.lgp_regs, &linux_regs, sizeof(linux_regs)); 183 184 fpu_save_lwp(curlwp, FPU_SAVE); 185 memcpy(&frame.lfp_regs, curpcb->pcb_fpu.fpreg, sizeof(frame.lfp_regs)); 186 187 /* 188 * Copy Linux's signal trampoline on the user stack It should not 189 * be used, but Linux binaries might expect it to be there. 190 */ 191 frame.ltramp[0] = 0x38997777; /* li r0, 0x7777 */ 192 frame.ltramp[1] = 0x44000002; /* sc */ 193 194 /* 195 * Move it to the user stack 196 * There is a little trick here, about the LINUX_ABIGAP: the 197 * linux_sigreg structure has a 56 int gap to support rs6000/xcoff 198 * binaries. But the Linux kernel seems to do without it, and it 199 * just skip it when building the stack frame. Hence the LINUX_ABIGAP. 200 */ 201 sendsig_reset(l, sig); 202 mutex_exit(p->p_lock); 203 error = copyout(&frame, (void *)fp, sizeof (frame) - LINUX_ABIGAP); 204 205 if (error != 0) { 206 /* 207 * Process has trashed its stack; give it an illegal 208 * instruction to halt it in its tracks. 209 */ 210 mutex_enter(p->p_lock); 211 sigexit(l, SIGILL); 212 /* NOTREACHED */ 213 } 214 215 /* 216 * Add a sigcontext on the stack 217 */ 218 fp -= sizeof(struct linux_sigcontext); 219 error = copyout(&sc, (void *)fp, sizeof (struct linux_sigcontext)); 220 mutex_enter(p->p_lock); 221 222 if (error != 0) { 223 /* 224 * Process has trashed its stack; give it an illegal 225 * instruction to halt it in its tracks. 226 */ 227 sigexit(l, SIGILL); 228 /* NOTREACHED */ 229 } 230 231 /* 232 * Set the registers according to how the Linux process expects them. 233 * "Mind the gap" Linux expects a gap here. 234 */ 235 tf->tf_fixreg[1] = fp - LINUX__SIGNAL_FRAMESIZE; 236 tf->tf_lr = (int)catcher; 237 tf->tf_fixreg[3] = (int)native_to_linux_signo[sig]; 238 tf->tf_fixreg[4] = fp; 239 tf->tf_srr0 = (int)p->p_sigctx.ps_sigcode; 240 241 #ifdef DEBUG_LINUX 242 printf("fp at end of linux_sendsig = %x\n", fp); 243 #endif 244 /* 245 * Remember that we're now on the signal stack. 246 */ 247 if (onstack) 248 l->l_sigstk.ss_flags |= SS_ONSTACK; 249 #ifdef DEBUG_LINUX 250 printf("linux_sendsig: exitting. fp=0x%lx\n",(long)fp); 251 #endif 252 } 253 254 /* 255 * System call to cleanup state after a signal 256 * has been taken. Reset signal mask and 257 * stack state from context left by sendsig (above). 258 * Return to previous pc and psl as specified by 259 * context left by sendsig. Check carefully to 260 * make sure that the user has not modified the 261 * psl to gain improper privileges or to cause 262 * a machine fault. 263 * 264 * XXX not tested 265 */ 266 int 267 linux_sys_rt_sigreturn(struct lwp *l, const struct linux_sys_rt_sigreturn_args *uap, register_t *retval) 268 { 269 /* { 270 syscallarg(struct linux_rt_sigframe *) sfp; 271 } */ 272 struct proc *p = l->l_proc; 273 struct linux_rt_sigframe *scp, sigframe; 274 struct linux_sigregs sregs; 275 struct linux_pt_regs *lregs; 276 struct trapframe *tf; 277 sigset_t mask; 278 int i; 279 280 /* 281 * The trampoline code hands us the context. 282 * It is unsafe to keep track of it ourselves, in the event that a 283 * program jumps out of a signal handler. 284 */ 285 scp = SCARG(uap, sfp); 286 287 /* 288 * Get the context from user stack 289 */ 290 if (copyin((void *)scp, &sigframe, sizeof(*scp))) 291 return (EFAULT); 292 293 /* 294 * Restore register context. 295 */ 296 if (copyin((void *)sigframe.luc.luc_context.lregs, 297 &sregs, sizeof(sregs))) 298 return (EFAULT); 299 lregs = (struct linux_pt_regs *)&sregs.lgp_regs; 300 301 tf = trapframe(l); 302 #ifdef DEBUG_LINUX 303 printf("linux_sys_rt_sigreturn: trapframe=0x%lx scp=0x%lx\n", 304 (unsigned long)tf, (unsigned long)scp); 305 #endif 306 307 if (!PSL_USEROK_P(lregs->lmsr)) 308 return (EINVAL); 309 310 for (i = 0; i < 32; i++) 311 tf->tf_fixreg[i] = lregs->lgpr[i]; 312 tf->tf_lr = lregs->llink; 313 tf->tf_cr = lregs->lccr; 314 tf->tf_xer = lregs->lxer; 315 tf->tf_ctr = lregs->lctr; 316 tf->tf_srr0 = lregs->lnip; 317 tf->tf_srr1 = lregs->lmsr; 318 319 /* 320 * Make sure the fpu state is discarded 321 */ 322 fpu_save_lwp(curlwp, FPU_DISCARD); 323 324 memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs, 325 sizeof(curpcb->pcb_fpu.fpreg)); 326 327 mutex_enter(p->p_lock); 328 329 /* 330 * Restore signal stack. 331 * 332 * XXX cannot find the onstack information in Linux sig context. 333 * Is signal stack really supported on Linux? 334 * 335 * It seems to be supported in libc6... 336 */ 337 /* if (sc.sc_onstack & SS_ONSTACK) 338 l->l_sigstk.ss_flags |= SS_ONSTACK; 339 else */ 340 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 341 342 /* 343 * Grab the signal mask 344 */ 345 linux_to_native_sigset(&mask, &sigframe.luc.luc_sigmask); 346 (void) sigprocmask1(l, SIG_SETMASK, &mask, 0); 347 348 mutex_exit(p->p_lock); 349 350 return (EJUSTRETURN); 351 } 352 353 354 /* 355 * The following needs code review for potential security issues 356 */ 357 int 358 linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval) 359 { 360 /* { 361 syscallarg(struct linux_sigcontext *) scp; 362 } */ 363 struct proc *p = l->l_proc; 364 struct linux_sigcontext *scp, context; 365 struct linux_sigregs sregs; 366 struct linux_pt_regs *lregs; 367 struct trapframe *tf; 368 sigset_t mask; 369 int i; 370 371 /* 372 * The trampoline code hands us the context. 373 * It is unsafe to keep track of it ourselves, in the event that a 374 * program jumps out of a signal handler. 375 */ 376 scp = SCARG(uap, scp); 377 378 /* 379 * Get the context from user stack 380 */ 381 if (copyin(scp, &context, sizeof(*scp))) 382 return (EFAULT); 383 384 /* 385 * Restore register context. 386 */ 387 if (copyin((void *)context.lregs, &sregs, sizeof(sregs))) 388 return (EFAULT); 389 lregs = (struct linux_pt_regs *)&sregs.lgp_regs; 390 391 tf = trapframe(l); 392 #ifdef DEBUG_LINUX 393 printf("linux_sys_sigreturn: trapframe=0x%lx scp=0x%lx\n", 394 (unsigned long)tf, (unsigned long)scp); 395 #endif 396 397 if (!PSL_USEROK_P(lregs->lmsr)) 398 return (EINVAL); 399 400 for (i = 0; i < 32; i++) 401 tf->tf_fixreg[i] = lregs->lgpr[i]; 402 tf->tf_lr = lregs->llink; 403 tf->tf_cr = lregs->lccr; 404 tf->tf_xer = lregs->lxer; 405 tf->tf_ctr = lregs->lctr; 406 tf->tf_srr0 = lregs->lnip; 407 tf->tf_srr1 = lregs->lmsr; 408 409 /* 410 * Make sure the fpu state is discarded 411 */ 412 fpu_save_lwp(curlwp, FPU_DISCARD); 413 414 memcpy(curpcb->pcb_fpu.fpreg, (void *)&sregs.lfp_regs, 415 sizeof(curpcb->pcb_fpu.fpreg)); 416 417 mutex_enter(p->p_lock); 418 419 /* 420 * Restore signal stack. 421 * 422 * XXX cannot find the onstack information in Linux sig context. 423 * Is signal stack really supported on Linux? 424 */ 425 #if 0 426 if (sc.sc_onstack & SS_ONSTACK) 427 l->l_sigstk.ss_flags |= SS_ONSTACK; 428 else 429 #endif 430 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 431 432 /* Restore signal mask. */ 433 linux_old_extra_to_native_sigset(&mask, &context.lmask, 434 &context._unused[3]); 435 (void) sigprocmask1(l, SIG_SETMASK, &mask, 0); 436 437 mutex_exit(p->p_lock); 438 439 return (EJUSTRETURN); 440 } 441 442 /* 443 * major device numbers remapping 444 */ 445 dev_t 446 linux_fakedev(dev_t dev, int raw) 447 { 448 /* XXX write me */ 449 return dev; 450 } 451 452 /* 453 * We come here in a last attempt to satisfy a Linux ioctl() call 454 */ 455 int 456 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *uap, register_t *retval) 457 { 458 /* { 459 syscallarg(int) fd; 460 syscallarg(u_long) com; 461 syscallarg(void *) data; 462 } */ 463 struct sys_ioctl_args bia; 464 u_long com; 465 466 SCARG(&bia, fd) = SCARG(uap, fd); 467 SCARG(&bia, data) = SCARG(uap, data); 468 com = SCARG(uap, com); 469 470 switch (com) { 471 default: 472 printf("linux_machdepioctl: invalid ioctl %08lx\n", com); 473 return EINVAL; 474 } 475 SCARG(&bia, com) = com; 476 /* XXX NJWLWP */ 477 return sys_ioctl(curlwp, &bia, retval); 478 } 479 480 /* 481 * wrapper linux_sys_new_uname() -> linux_sys_uname() 482 */ 483 int 484 linux_sys_new_uname(struct lwp *l, const struct linux_sys_new_uname_args *uap, register_t *retval) 485 { 486 return linux_sys_uname(l, (const void *)uap, retval); 487 } 488 489 /* 490 * wrapper linux_sys_new_select() -> linux_sys_select() 491 */ 492 int 493 linux_sys_new_select(struct lwp *l, const struct linux_sys_new_select_args *uap, register_t *retval) 494 { 495 return linux_sys_select(l, (const void *)uap, retval); 496 } 497 498 int 499 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg) 500 { 501 return 0; 502 } 503