1 /* 2 * linux/arch/m68k/kernel/signal.c 3 * 4 * Copyright (C) 1991, 1992 Linus Torvalds 5 * 6 * This file is subject to the terms and conditions of the GNU General Public 7 * License. See the file COPYING in the main directory of this archive 8 * for more details. 9 */ 10 11 /* 12 * Linux/m68k support by Hamish Macdonald 13 * 14 * 68060 fixes by Jesper Skov 15 * 16 * 1997-12-01 Modified for POSIX.1b signals by Andreas Schwab 17 * 18 * mathemu support by Roman Zippel 19 * (Note: fpstate in the signal context is completely ignored for the emulator 20 * and the internal floating point format is put on stack) 21 */ 22 23 /* 24 * ++roman (07/09/96): implemented signal stacks (specially for tosemu on 25 * Atari :-) Current limitation: Only one sigstack can be active at one time. 26 * If a second signal with SA_ONSTACK set arrives while working on a sigstack, 27 * SA_ONSTACK is ignored. This behaviour avoids lots of trouble with nested 28 * signal handlers! 29 */ 30 31 #include <linux/sched.h> 32 #include <linux/mm.h> 33 #include <linux/kernel.h> 34 #include <linux/signal.h> 35 #include <linux/syscalls.h> 36 #include <linux/errno.h> 37 #include <linux/wait.h> 38 #include <linux/ptrace.h> 39 #include <linux/unistd.h> 40 #include <linux/stddef.h> 41 #include <linux/highuid.h> 42 #include <linux/personality.h> 43 #include <linux/tty.h> 44 #include <linux/binfmts.h> 45 #include <linux/module.h> 46 #include <linux/tracehook.h> 47 48 #include <asm/setup.h> 49 #include <asm/uaccess.h> 50 #include <asm/pgtable.h> 51 #include <asm/traps.h> 52 #include <asm/ucontext.h> 53 54 #ifdef CONFIG_MMU 55 56 /* 57 * Handle the slight differences in classic 68k and ColdFire trap frames. 58 */ 59 #ifdef CONFIG_COLDFIRE 60 #define FORMAT 4 61 #define FMT4SIZE 0 62 #else 63 #define FORMAT 0 64 #define FMT4SIZE sizeof(((struct frame *)0)->un.fmt4) 65 #endif 66 67 static const int frame_size_change[16] = { 68 [1] = -1, /* sizeof(((struct frame *)0)->un.fmt1), */ 69 [2] = sizeof(((struct frame *)0)->un.fmt2), 70 [3] = sizeof(((struct frame *)0)->un.fmt3), 71 [4] = FMT4SIZE, 72 [5] = -1, /* sizeof(((struct frame *)0)->un.fmt5), */ 73 [6] = -1, /* sizeof(((struct frame *)0)->un.fmt6), */ 74 [7] = sizeof(((struct frame *)0)->un.fmt7), 75 [8] = -1, /* sizeof(((struct frame *)0)->un.fmt8), */ 76 [9] = sizeof(((struct frame *)0)->un.fmt9), 77 [10] = sizeof(((struct frame *)0)->un.fmta), 78 [11] = sizeof(((struct frame *)0)->un.fmtb), 79 [12] = -1, /* sizeof(((struct frame *)0)->un.fmtc), */ 80 [13] = -1, /* sizeof(((struct frame *)0)->un.fmtd), */ 81 [14] = -1, /* sizeof(((struct frame *)0)->un.fmte), */ 82 [15] = -1, /* sizeof(((struct frame *)0)->un.fmtf), */ 83 }; 84 85 static inline int frame_extra_sizes(int f) 86 { 87 return frame_size_change[f]; 88 } 89 90 int handle_kernel_fault(struct pt_regs *regs) 91 { 92 const struct exception_table_entry *fixup; 93 struct pt_regs *tregs; 94 95 /* Are we prepared to handle this kernel fault? */ 96 fixup = search_exception_tables(regs->pc); 97 if (!fixup) 98 return 0; 99 100 /* Create a new four word stack frame, discarding the old one. */ 101 regs->stkadj = frame_extra_sizes(regs->format); 102 tregs = (struct pt_regs *)((long)regs + regs->stkadj); 103 tregs->vector = regs->vector; 104 tregs->format = FORMAT; 105 tregs->pc = fixup->fixup; 106 tregs->sr = regs->sr; 107 108 return 1; 109 } 110 111 void ptrace_signal_deliver(void) 112 { 113 struct pt_regs *regs = signal_pt_regs(); 114 if (regs->orig_d0 < 0) 115 return; 116 switch (regs->d0) { 117 case -ERESTARTNOHAND: 118 case -ERESTARTSYS: 119 case -ERESTARTNOINTR: 120 regs->d0 = regs->orig_d0; 121 regs->orig_d0 = -1; 122 regs->pc -= 2; 123 break; 124 } 125 } 126 127 static inline void push_cache (unsigned long vaddr) 128 { 129 /* 130 * Using the old cache_push_v() was really a big waste. 131 * 132 * What we are trying to do is to flush 8 bytes to ram. 133 * Flushing 2 cache lines of 16 bytes is much cheaper than 134 * flushing 1 or 2 pages, as previously done in 135 * cache_push_v(). 136 * Jes 137 */ 138 if (CPU_IS_040) { 139 unsigned long temp; 140 141 __asm__ __volatile__ (".chip 68040\n\t" 142 "nop\n\t" 143 "ptestr (%1)\n\t" 144 "movec %%mmusr,%0\n\t" 145 ".chip 68k" 146 : "=r" (temp) 147 : "a" (vaddr)); 148 149 temp &= PAGE_MASK; 150 temp |= vaddr & ~PAGE_MASK; 151 152 __asm__ __volatile__ (".chip 68040\n\t" 153 "nop\n\t" 154 "cpushl %%bc,(%0)\n\t" 155 ".chip 68k" 156 : : "a" (temp)); 157 } 158 else if (CPU_IS_060) { 159 unsigned long temp; 160 __asm__ __volatile__ (".chip 68060\n\t" 161 "plpar (%0)\n\t" 162 ".chip 68k" 163 : "=a" (temp) 164 : "0" (vaddr)); 165 __asm__ __volatile__ (".chip 68060\n\t" 166 "cpushl %%bc,(%0)\n\t" 167 ".chip 68k" 168 : : "a" (temp)); 169 } else if (!CPU_IS_COLDFIRE) { 170 /* 171 * 68030/68020 have no writeback cache; 172 * still need to clear icache. 173 * Note that vaddr is guaranteed to be long word aligned. 174 */ 175 unsigned long temp; 176 asm volatile ("movec %%cacr,%0" : "=r" (temp)); 177 temp += 4; 178 asm volatile ("movec %0,%%caar\n\t" 179 "movec %1,%%cacr" 180 : : "r" (vaddr), "r" (temp)); 181 asm volatile ("movec %0,%%caar\n\t" 182 "movec %1,%%cacr" 183 : : "r" (vaddr + 4), "r" (temp)); 184 } 185 } 186 187 static inline void adjustformat(struct pt_regs *regs) 188 { 189 } 190 191 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 192 { 193 } 194 195 #else /* CONFIG_MMU */ 196 197 void ret_from_user_signal(void); 198 void ret_from_user_rt_signal(void); 199 200 static inline int frame_extra_sizes(int f) 201 { 202 /* No frame size adjustments required on non-MMU CPUs */ 203 return 0; 204 } 205 206 static inline void adjustformat(struct pt_regs *regs) 207 { 208 ((struct switch_stack *)regs - 1)->a5 = current->mm->start_data; 209 /* 210 * set format byte to make stack appear modulo 4, which it will 211 * be when doing the rte 212 */ 213 regs->format = 0x4; 214 } 215 216 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 217 { 218 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5; 219 } 220 221 static inline void push_cache(unsigned long vaddr) 222 { 223 } 224 225 #endif /* CONFIG_MMU */ 226 227 /* 228 * Atomically swap in the new signal mask, and wait for a signal. 229 */ 230 asmlinkage int 231 sys_sigsuspend(int unused0, int unused1, old_sigset_t mask) 232 { 233 sigset_t blocked; 234 siginitset(&blocked, mask); 235 return sigsuspend(&blocked); 236 } 237 238 asmlinkage int 239 sys_sigaction(int sig, const struct old_sigaction __user *act, 240 struct old_sigaction __user *oact) 241 { 242 struct k_sigaction new_ka, old_ka; 243 int ret; 244 245 if (act) { 246 old_sigset_t mask; 247 if (!access_ok(VERIFY_READ, act, sizeof(*act)) || 248 __get_user(new_ka.sa.sa_handler, &act->sa_handler) || 249 __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) || 250 __get_user(new_ka.sa.sa_flags, &act->sa_flags) || 251 __get_user(mask, &act->sa_mask)) 252 return -EFAULT; 253 siginitset(&new_ka.sa.sa_mask, mask); 254 } 255 256 ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); 257 258 if (!ret && oact) { 259 if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || 260 __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || 261 __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) || 262 __put_user(old_ka.sa.sa_flags, &oact->sa_flags) || 263 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask)) 264 return -EFAULT; 265 } 266 267 return ret; 268 } 269 270 asmlinkage int 271 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss) 272 { 273 return do_sigaltstack(uss, uoss, rdusp()); 274 } 275 276 277 /* 278 * Do a signal return; undo the signal stack. 279 * 280 * Keep the return code on the stack quadword aligned! 281 * That makes the cache flush below easier. 282 */ 283 284 struct sigframe 285 { 286 char __user *pretcode; 287 int sig; 288 int code; 289 struct sigcontext __user *psc; 290 char retcode[8]; 291 unsigned long extramask[_NSIG_WORDS-1]; 292 struct sigcontext sc; 293 }; 294 295 struct rt_sigframe 296 { 297 char __user *pretcode; 298 int sig; 299 struct siginfo __user *pinfo; 300 void __user *puc; 301 char retcode[8]; 302 struct siginfo info; 303 struct ucontext uc; 304 }; 305 306 #define FPCONTEXT_SIZE 216 307 #define uc_fpstate uc_filler[0] 308 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] 309 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] 310 311 #ifdef CONFIG_FPU 312 313 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ 314 315 static inline int restore_fpu_state(struct sigcontext *sc) 316 { 317 int err = 1; 318 319 if (FPU_IS_EMU) { 320 /* restore registers */ 321 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); 322 memcpy(current->thread.fp, sc->sc_fpregs, 24); 323 return 0; 324 } 325 326 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 327 /* Verify the frame format. */ 328 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 329 (sc->sc_fpstate[0] != fpu_version)) 330 goto out; 331 if (CPU_IS_020_OR_030) { 332 if (m68k_fputype & FPU_68881 && 333 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) 334 goto out; 335 if (m68k_fputype & FPU_68882 && 336 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) 337 goto out; 338 } else if (CPU_IS_040) { 339 if (!(sc->sc_fpstate[1] == 0x00 || 340 sc->sc_fpstate[1] == 0x28 || 341 sc->sc_fpstate[1] == 0x60)) 342 goto out; 343 } else if (CPU_IS_060) { 344 if (!(sc->sc_fpstate[3] == 0x00 || 345 sc->sc_fpstate[3] == 0x60 || 346 sc->sc_fpstate[3] == 0xe0)) 347 goto out; 348 } else if (CPU_IS_COLDFIRE) { 349 if (!(sc->sc_fpstate[0] == 0x00 || 350 sc->sc_fpstate[0] == 0x05 || 351 sc->sc_fpstate[0] == 0xe5)) 352 goto out; 353 } else 354 goto out; 355 356 if (CPU_IS_COLDFIRE) { 357 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t" 358 "fmovel %1,%%fpcr\n\t" 359 "fmovel %2,%%fpsr\n\t" 360 "fmovel %3,%%fpiar" 361 : /* no outputs */ 362 : "m" (sc->sc_fpregs[0]), 363 "m" (sc->sc_fpcntl[0]), 364 "m" (sc->sc_fpcntl[1]), 365 "m" (sc->sc_fpcntl[2])); 366 } else { 367 __asm__ volatile (".chip 68k/68881\n\t" 368 "fmovemx %0,%%fp0-%%fp1\n\t" 369 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 370 ".chip 68k" 371 : /* no outputs */ 372 : "m" (*sc->sc_fpregs), 373 "m" (*sc->sc_fpcntl)); 374 } 375 } 376 377 if (CPU_IS_COLDFIRE) { 378 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate)); 379 } else { 380 __asm__ volatile (".chip 68k/68881\n\t" 381 "frestore %0\n\t" 382 ".chip 68k" 383 : : "m" (*sc->sc_fpstate)); 384 } 385 err = 0; 386 387 out: 388 return err; 389 } 390 391 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 392 { 393 unsigned char fpstate[FPCONTEXT_SIZE]; 394 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 395 fpregset_t fpregs; 396 int err = 1; 397 398 if (FPU_IS_EMU) { 399 /* restore fpu control register */ 400 if (__copy_from_user(current->thread.fpcntl, 401 uc->uc_mcontext.fpregs.f_fpcntl, 12)) 402 goto out; 403 /* restore all other fpu register */ 404 if (__copy_from_user(current->thread.fp, 405 uc->uc_mcontext.fpregs.f_fpregs, 96)) 406 goto out; 407 return 0; 408 } 409 410 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate)) 411 goto out; 412 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 413 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 414 context_size = fpstate[1]; 415 /* Verify the frame format. */ 416 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 417 (fpstate[0] != fpu_version)) 418 goto out; 419 if (CPU_IS_020_OR_030) { 420 if (m68k_fputype & FPU_68881 && 421 !(context_size == 0x18 || context_size == 0xb4)) 422 goto out; 423 if (m68k_fputype & FPU_68882 && 424 !(context_size == 0x38 || context_size == 0xd4)) 425 goto out; 426 } else if (CPU_IS_040) { 427 if (!(context_size == 0x00 || 428 context_size == 0x28 || 429 context_size == 0x60)) 430 goto out; 431 } else if (CPU_IS_060) { 432 if (!(fpstate[3] == 0x00 || 433 fpstate[3] == 0x60 || 434 fpstate[3] == 0xe0)) 435 goto out; 436 } else if (CPU_IS_COLDFIRE) { 437 if (!(fpstate[3] == 0x00 || 438 fpstate[3] == 0x05 || 439 fpstate[3] == 0xe5)) 440 goto out; 441 } else 442 goto out; 443 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, 444 sizeof(fpregs))) 445 goto out; 446 447 if (CPU_IS_COLDFIRE) { 448 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t" 449 "fmovel %1,%%fpcr\n\t" 450 "fmovel %2,%%fpsr\n\t" 451 "fmovel %3,%%fpiar" 452 : /* no outputs */ 453 : "m" (fpregs.f_fpregs[0]), 454 "m" (fpregs.f_fpcntl[0]), 455 "m" (fpregs.f_fpcntl[1]), 456 "m" (fpregs.f_fpcntl[2])); 457 } else { 458 __asm__ volatile (".chip 68k/68881\n\t" 459 "fmovemx %0,%%fp0-%%fp7\n\t" 460 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 461 ".chip 68k" 462 : /* no outputs */ 463 : "m" (*fpregs.f_fpregs), 464 "m" (*fpregs.f_fpcntl)); 465 } 466 } 467 if (context_size && 468 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1, 469 context_size)) 470 goto out; 471 472 if (CPU_IS_COLDFIRE) { 473 __asm__ volatile ("frestore %0" : : "m" (*fpstate)); 474 } else { 475 __asm__ volatile (".chip 68k/68881\n\t" 476 "frestore %0\n\t" 477 ".chip 68k" 478 : : "m" (*fpstate)); 479 } 480 err = 0; 481 482 out: 483 return err; 484 } 485 486 /* 487 * Set up a signal frame. 488 */ 489 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 490 { 491 if (FPU_IS_EMU) { 492 /* save registers */ 493 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); 494 memcpy(sc->sc_fpregs, current->thread.fp, 24); 495 return; 496 } 497 498 if (CPU_IS_COLDFIRE) { 499 __asm__ volatile ("fsave %0" 500 : : "m" (*sc->sc_fpstate) : "memory"); 501 } else { 502 __asm__ volatile (".chip 68k/68881\n\t" 503 "fsave %0\n\t" 504 ".chip 68k" 505 : : "m" (*sc->sc_fpstate) : "memory"); 506 } 507 508 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 509 fpu_version = sc->sc_fpstate[0]; 510 if (CPU_IS_020_OR_030 && 511 regs->vector >= (VEC_FPBRUC * 4) && 512 regs->vector <= (VEC_FPNAN * 4)) { 513 /* Clear pending exception in 68882 idle frame */ 514 if (*(unsigned short *) sc->sc_fpstate == 0x1f38) 515 sc->sc_fpstate[0x38] |= 1 << 3; 516 } 517 518 if (CPU_IS_COLDFIRE) { 519 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t" 520 "fmovel %%fpcr,%1\n\t" 521 "fmovel %%fpsr,%2\n\t" 522 "fmovel %%fpiar,%3" 523 : "=m" (sc->sc_fpregs[0]), 524 "=m" (sc->sc_fpcntl[0]), 525 "=m" (sc->sc_fpcntl[1]), 526 "=m" (sc->sc_fpcntl[2]) 527 : /* no inputs */ 528 : "memory"); 529 } else { 530 __asm__ volatile (".chip 68k/68881\n\t" 531 "fmovemx %%fp0-%%fp1,%0\n\t" 532 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 533 ".chip 68k" 534 : "=m" (*sc->sc_fpregs), 535 "=m" (*sc->sc_fpcntl) 536 : /* no inputs */ 537 : "memory"); 538 } 539 } 540 } 541 542 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 543 { 544 unsigned char fpstate[FPCONTEXT_SIZE]; 545 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 546 int err = 0; 547 548 if (FPU_IS_EMU) { 549 /* save fpu control register */ 550 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, 551 current->thread.fpcntl, 12); 552 /* save all other fpu register */ 553 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, 554 current->thread.fp, 96); 555 return err; 556 } 557 558 if (CPU_IS_COLDFIRE) { 559 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory"); 560 } else { 561 __asm__ volatile (".chip 68k/68881\n\t" 562 "fsave %0\n\t" 563 ".chip 68k" 564 : : "m" (*fpstate) : "memory"); 565 } 566 567 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate); 568 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 569 fpregset_t fpregs; 570 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 571 context_size = fpstate[1]; 572 fpu_version = fpstate[0]; 573 if (CPU_IS_020_OR_030 && 574 regs->vector >= (VEC_FPBRUC * 4) && 575 regs->vector <= (VEC_FPNAN * 4)) { 576 /* Clear pending exception in 68882 idle frame */ 577 if (*(unsigned short *) fpstate == 0x1f38) 578 fpstate[0x38] |= 1 << 3; 579 } 580 if (CPU_IS_COLDFIRE) { 581 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t" 582 "fmovel %%fpcr,%1\n\t" 583 "fmovel %%fpsr,%2\n\t" 584 "fmovel %%fpiar,%3" 585 : "=m" (fpregs.f_fpregs[0]), 586 "=m" (fpregs.f_fpcntl[0]), 587 "=m" (fpregs.f_fpcntl[1]), 588 "=m" (fpregs.f_fpcntl[2]) 589 : /* no inputs */ 590 : "memory"); 591 } else { 592 __asm__ volatile (".chip 68k/68881\n\t" 593 "fmovemx %%fp0-%%fp7,%0\n\t" 594 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 595 ".chip 68k" 596 : "=m" (*fpregs.f_fpregs), 597 "=m" (*fpregs.f_fpcntl) 598 : /* no inputs */ 599 : "memory"); 600 } 601 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, 602 sizeof(fpregs)); 603 } 604 if (context_size) 605 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4, 606 context_size); 607 return err; 608 } 609 610 #else /* CONFIG_FPU */ 611 612 /* 613 * For the case with no FPU configured these all do nothing. 614 */ 615 static inline int restore_fpu_state(struct sigcontext *sc) 616 { 617 return 0; 618 } 619 620 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 621 { 622 return 0; 623 } 624 625 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 626 { 627 } 628 629 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 630 { 631 return 0; 632 } 633 634 #endif /* CONFIG_FPU */ 635 636 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, 637 void __user *fp) 638 { 639 int fsize = frame_extra_sizes(formatvec >> 12); 640 if (fsize < 0) { 641 /* 642 * user process trying to return with weird frame format 643 */ 644 #ifdef DEBUG 645 printk("user process returning with weird frame format\n"); 646 #endif 647 return 1; 648 } 649 if (!fsize) { 650 regs->format = formatvec >> 12; 651 regs->vector = formatvec & 0xfff; 652 } else { 653 struct switch_stack *sw = (struct switch_stack *)regs - 1; 654 unsigned long buf[fsize / 2]; /* yes, twice as much */ 655 656 /* that'll make sure that expansion won't crap over data */ 657 if (copy_from_user(buf + fsize / 4, fp, fsize)) 658 return 1; 659 660 /* point of no return */ 661 regs->format = formatvec >> 12; 662 regs->vector = formatvec & 0xfff; 663 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) 664 __asm__ __volatile__ ( 665 #ifdef CONFIG_COLDFIRE 666 " movel %0,%/sp\n\t" 667 " bra ret_from_signal\n" 668 #else 669 " movel %0,%/a0\n\t" 670 " subl %1,%/a0\n\t" /* make room on stack */ 671 " movel %/a0,%/sp\n\t" /* set stack pointer */ 672 /* move switch_stack and pt_regs */ 673 "1: movel %0@+,%/a0@+\n\t" 674 " dbra %2,1b\n\t" 675 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ 676 " lsrl #2,%1\n\t" 677 " subql #1,%1\n\t" 678 /* copy to the gap we'd made */ 679 "2: movel %4@+,%/a0@+\n\t" 680 " dbra %1,2b\n\t" 681 " bral ret_from_signal\n" 682 #endif 683 : /* no outputs, it doesn't ever return */ 684 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), 685 "n" (frame_offset), "a" (buf + fsize/4) 686 : "a0"); 687 #undef frame_offset 688 } 689 return 0; 690 } 691 692 static inline int 693 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) 694 { 695 int formatvec; 696 struct sigcontext context; 697 int err = 0; 698 699 /* Always make any pending restarted system calls return -EINTR */ 700 current_thread_info()->restart_block.fn = do_no_restart_syscall; 701 702 /* get previous context */ 703 if (copy_from_user(&context, usc, sizeof(context))) 704 goto badframe; 705 706 /* restore passed registers */ 707 regs->d0 = context.sc_d0; 708 regs->d1 = context.sc_d1; 709 regs->a0 = context.sc_a0; 710 regs->a1 = context.sc_a1; 711 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); 712 regs->pc = context.sc_pc; 713 regs->orig_d0 = -1; /* disable syscall checks */ 714 wrusp(context.sc_usp); 715 formatvec = context.sc_formatvec; 716 717 err = restore_fpu_state(&context); 718 719 if (err || mangle_kernel_stack(regs, formatvec, fp)) 720 goto badframe; 721 722 return 0; 723 724 badframe: 725 return 1; 726 } 727 728 static inline int 729 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, 730 struct ucontext __user *uc) 731 { 732 int temp; 733 greg_t __user *gregs = uc->uc_mcontext.gregs; 734 unsigned long usp; 735 int err; 736 737 /* Always make any pending restarted system calls return -EINTR */ 738 current_thread_info()->restart_block.fn = do_no_restart_syscall; 739 740 err = __get_user(temp, &uc->uc_mcontext.version); 741 if (temp != MCONTEXT_VERSION) 742 goto badframe; 743 /* restore passed registers */ 744 err |= __get_user(regs->d0, &gregs[0]); 745 err |= __get_user(regs->d1, &gregs[1]); 746 err |= __get_user(regs->d2, &gregs[2]); 747 err |= __get_user(regs->d3, &gregs[3]); 748 err |= __get_user(regs->d4, &gregs[4]); 749 err |= __get_user(regs->d5, &gregs[5]); 750 err |= __get_user(sw->d6, &gregs[6]); 751 err |= __get_user(sw->d7, &gregs[7]); 752 err |= __get_user(regs->a0, &gregs[8]); 753 err |= __get_user(regs->a1, &gregs[9]); 754 err |= __get_user(regs->a2, &gregs[10]); 755 err |= __get_user(sw->a3, &gregs[11]); 756 err |= __get_user(sw->a4, &gregs[12]); 757 err |= __get_user(sw->a5, &gregs[13]); 758 err |= __get_user(sw->a6, &gregs[14]); 759 err |= __get_user(usp, &gregs[15]); 760 wrusp(usp); 761 err |= __get_user(regs->pc, &gregs[16]); 762 err |= __get_user(temp, &gregs[17]); 763 regs->sr = (regs->sr & 0xff00) | (temp & 0xff); 764 regs->orig_d0 = -1; /* disable syscall checks */ 765 err |= __get_user(temp, &uc->uc_formatvec); 766 767 err |= rt_restore_fpu_state(uc); 768 769 if (err || do_sigaltstack(&uc->uc_stack, NULL, usp) == -EFAULT) 770 goto badframe; 771 772 if (mangle_kernel_stack(regs, temp, &uc->uc_extra)) 773 goto badframe; 774 775 return 0; 776 777 badframe: 778 return 1; 779 } 780 781 asmlinkage int do_sigreturn(unsigned long __unused) 782 { 783 struct switch_stack *sw = (struct switch_stack *) &__unused; 784 struct pt_regs *regs = (struct pt_regs *) (sw + 1); 785 unsigned long usp = rdusp(); 786 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 787 sigset_t set; 788 789 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 790 goto badframe; 791 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 792 (_NSIG_WORDS > 1 && 793 __copy_from_user(&set.sig[1], &frame->extramask, 794 sizeof(frame->extramask)))) 795 goto badframe; 796 797 set_current_blocked(&set); 798 799 if (restore_sigcontext(regs, &frame->sc, frame + 1)) 800 goto badframe; 801 return regs->d0; 802 803 badframe: 804 force_sig(SIGSEGV, current); 805 return 0; 806 } 807 808 asmlinkage int do_rt_sigreturn(unsigned long __unused) 809 { 810 struct switch_stack *sw = (struct switch_stack *) &__unused; 811 struct pt_regs *regs = (struct pt_regs *) (sw + 1); 812 unsigned long usp = rdusp(); 813 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 814 sigset_t set; 815 816 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 817 goto badframe; 818 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 819 goto badframe; 820 821 set_current_blocked(&set); 822 823 if (rt_restore_ucontext(regs, sw, &frame->uc)) 824 goto badframe; 825 return regs->d0; 826 827 badframe: 828 force_sig(SIGSEGV, current); 829 return 0; 830 } 831 832 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 833 unsigned long mask) 834 { 835 sc->sc_mask = mask; 836 sc->sc_usp = rdusp(); 837 sc->sc_d0 = regs->d0; 838 sc->sc_d1 = regs->d1; 839 sc->sc_a0 = regs->a0; 840 sc->sc_a1 = regs->a1; 841 sc->sc_sr = regs->sr; 842 sc->sc_pc = regs->pc; 843 sc->sc_formatvec = regs->format << 12 | regs->vector; 844 save_a5_state(sc, regs); 845 save_fpu_state(sc, regs); 846 } 847 848 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 849 { 850 struct switch_stack *sw = (struct switch_stack *)regs - 1; 851 greg_t __user *gregs = uc->uc_mcontext.gregs; 852 int err = 0; 853 854 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 855 err |= __put_user(regs->d0, &gregs[0]); 856 err |= __put_user(regs->d1, &gregs[1]); 857 err |= __put_user(regs->d2, &gregs[2]); 858 err |= __put_user(regs->d3, &gregs[3]); 859 err |= __put_user(regs->d4, &gregs[4]); 860 err |= __put_user(regs->d5, &gregs[5]); 861 err |= __put_user(sw->d6, &gregs[6]); 862 err |= __put_user(sw->d7, &gregs[7]); 863 err |= __put_user(regs->a0, &gregs[8]); 864 err |= __put_user(regs->a1, &gregs[9]); 865 err |= __put_user(regs->a2, &gregs[10]); 866 err |= __put_user(sw->a3, &gregs[11]); 867 err |= __put_user(sw->a4, &gregs[12]); 868 err |= __put_user(sw->a5, &gregs[13]); 869 err |= __put_user(sw->a6, &gregs[14]); 870 err |= __put_user(rdusp(), &gregs[15]); 871 err |= __put_user(regs->pc, &gregs[16]); 872 err |= __put_user(regs->sr, &gregs[17]); 873 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); 874 err |= rt_save_fpu_state(uc, regs); 875 return err; 876 } 877 878 static inline void __user * 879 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) 880 { 881 unsigned long usp; 882 883 /* Default to using normal stack. */ 884 usp = rdusp(); 885 886 /* This is the X/Open sanctioned signal stack switching. */ 887 if (ka->sa.sa_flags & SA_ONSTACK) { 888 if (!sas_ss_flags(usp)) 889 usp = current->sas_ss_sp + current->sas_ss_size; 890 } 891 return (void __user *)((usp - frame_size) & -8UL); 892 } 893 894 static int setup_frame (int sig, struct k_sigaction *ka, 895 sigset_t *set, struct pt_regs *regs) 896 { 897 struct sigframe __user *frame; 898 int fsize = frame_extra_sizes(regs->format); 899 struct sigcontext context; 900 int err = 0; 901 902 if (fsize < 0) { 903 #ifdef DEBUG 904 printk ("setup_frame: Unknown frame format %#x\n", 905 regs->format); 906 #endif 907 goto give_sigsegv; 908 } 909 910 frame = get_sigframe(ka, regs, sizeof(*frame) + fsize); 911 912 if (fsize) 913 err |= copy_to_user (frame + 1, regs + 1, fsize); 914 915 err |= __put_user((current_thread_info()->exec_domain 916 && current_thread_info()->exec_domain->signal_invmap 917 && sig < 32 918 ? current_thread_info()->exec_domain->signal_invmap[sig] 919 : sig), 920 &frame->sig); 921 922 err |= __put_user(regs->vector, &frame->code); 923 err |= __put_user(&frame->sc, &frame->psc); 924 925 if (_NSIG_WORDS > 1) 926 err |= copy_to_user(frame->extramask, &set->sig[1], 927 sizeof(frame->extramask)); 928 929 setup_sigcontext(&context, regs, set->sig[0]); 930 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 931 932 /* Set up to return from userspace. */ 933 #ifdef CONFIG_MMU 934 err |= __put_user(frame->retcode, &frame->pretcode); 935 /* moveq #,d0; trap #0 */ 936 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 937 (long __user *)(frame->retcode)); 938 #else 939 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode); 940 #endif 941 942 if (err) 943 goto give_sigsegv; 944 945 push_cache ((unsigned long) &frame->retcode); 946 947 /* 948 * Set up registers for signal handler. All the state we are about 949 * to destroy is successfully copied to sigframe. 950 */ 951 wrusp ((unsigned long) frame); 952 regs->pc = (unsigned long) ka->sa.sa_handler; 953 adjustformat(regs); 954 955 /* 956 * This is subtle; if we build more than one sigframe, all but the 957 * first one will see frame format 0 and have fsize == 0, so we won't 958 * screw stkadj. 959 */ 960 if (fsize) 961 regs->stkadj = fsize; 962 963 /* Prepare to skip over the extra stuff in the exception frame. */ 964 if (regs->stkadj) { 965 struct pt_regs *tregs = 966 (struct pt_regs *)((ulong)regs + regs->stkadj); 967 #ifdef DEBUG 968 printk("Performing stackadjust=%04x\n", regs->stkadj); 969 #endif 970 /* This must be copied with decreasing addresses to 971 handle overlaps. */ 972 tregs->vector = 0; 973 tregs->format = 0; 974 tregs->pc = regs->pc; 975 tregs->sr = regs->sr; 976 } 977 return 0; 978 979 give_sigsegv: 980 force_sigsegv(sig, current); 981 return err; 982 } 983 984 static int setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info, 985 sigset_t *set, struct pt_regs *regs) 986 { 987 struct rt_sigframe __user *frame; 988 int fsize = frame_extra_sizes(regs->format); 989 int err = 0; 990 991 if (fsize < 0) { 992 #ifdef DEBUG 993 printk ("setup_frame: Unknown frame format %#x\n", 994 regs->format); 995 #endif 996 goto give_sigsegv; 997 } 998 999 frame = get_sigframe(ka, regs, sizeof(*frame)); 1000 1001 if (fsize) 1002 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 1003 1004 err |= __put_user((current_thread_info()->exec_domain 1005 && current_thread_info()->exec_domain->signal_invmap 1006 && sig < 32 1007 ? current_thread_info()->exec_domain->signal_invmap[sig] 1008 : sig), 1009 &frame->sig); 1010 err |= __put_user(&frame->info, &frame->pinfo); 1011 err |= __put_user(&frame->uc, &frame->puc); 1012 err |= copy_siginfo_to_user(&frame->info, info); 1013 1014 /* Create the ucontext. */ 1015 err |= __put_user(0, &frame->uc.uc_flags); 1016 err |= __put_user(NULL, &frame->uc.uc_link); 1017 err |= __put_user((void __user *)current->sas_ss_sp, 1018 &frame->uc.uc_stack.ss_sp); 1019 err |= __put_user(sas_ss_flags(rdusp()), 1020 &frame->uc.uc_stack.ss_flags); 1021 err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); 1022 err |= rt_setup_ucontext(&frame->uc, regs); 1023 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 1024 1025 /* Set up to return from userspace. */ 1026 #ifdef CONFIG_MMU 1027 err |= __put_user(frame->retcode, &frame->pretcode); 1028 #ifdef __mcoldfire__ 1029 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 1030 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 1031 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 1032 (long __user *)(frame->retcode + 4)); 1033 #else 1034 /* moveq #,d0; notb d0; trap #0 */ 1035 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 1036 (long __user *)(frame->retcode + 0)); 1037 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 1038 #endif 1039 #else 1040 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode); 1041 #endif /* CONFIG_MMU */ 1042 1043 if (err) 1044 goto give_sigsegv; 1045 1046 push_cache ((unsigned long) &frame->retcode); 1047 1048 /* 1049 * Set up registers for signal handler. All the state we are about 1050 * to destroy is successfully copied to sigframe. 1051 */ 1052 wrusp ((unsigned long) frame); 1053 regs->pc = (unsigned long) ka->sa.sa_handler; 1054 adjustformat(regs); 1055 1056 /* 1057 * This is subtle; if we build more than one sigframe, all but the 1058 * first one will see frame format 0 and have fsize == 0, so we won't 1059 * screw stkadj. 1060 */ 1061 if (fsize) 1062 regs->stkadj = fsize; 1063 1064 /* Prepare to skip over the extra stuff in the exception frame. */ 1065 if (regs->stkadj) { 1066 struct pt_regs *tregs = 1067 (struct pt_regs *)((ulong)regs + regs->stkadj); 1068 #ifdef DEBUG 1069 printk("Performing stackadjust=%04x\n", regs->stkadj); 1070 #endif 1071 /* This must be copied with decreasing addresses to 1072 handle overlaps. */ 1073 tregs->vector = 0; 1074 tregs->format = 0; 1075 tregs->pc = regs->pc; 1076 tregs->sr = regs->sr; 1077 } 1078 return 0; 1079 1080 give_sigsegv: 1081 force_sigsegv(sig, current); 1082 return err; 1083 } 1084 1085 static inline void 1086 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1087 { 1088 switch (regs->d0) { 1089 case -ERESTARTNOHAND: 1090 if (!has_handler) 1091 goto do_restart; 1092 regs->d0 = -EINTR; 1093 break; 1094 1095 case -ERESTART_RESTARTBLOCK: 1096 if (!has_handler) { 1097 regs->d0 = __NR_restart_syscall; 1098 regs->pc -= 2; 1099 break; 1100 } 1101 regs->d0 = -EINTR; 1102 break; 1103 1104 case -ERESTARTSYS: 1105 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1106 regs->d0 = -EINTR; 1107 break; 1108 } 1109 /* fallthrough */ 1110 case -ERESTARTNOINTR: 1111 do_restart: 1112 regs->d0 = regs->orig_d0; 1113 regs->pc -= 2; 1114 break; 1115 } 1116 } 1117 1118 /* 1119 * OK, we're invoking a handler 1120 */ 1121 static void 1122 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info, 1123 struct pt_regs *regs) 1124 { 1125 sigset_t *oldset = sigmask_to_save(); 1126 int err; 1127 /* are we from a system call? */ 1128 if (regs->orig_d0 >= 0) 1129 /* If so, check system call restarting.. */ 1130 handle_restart(regs, ka, 1); 1131 1132 /* set up the stack frame */ 1133 if (ka->sa.sa_flags & SA_SIGINFO) 1134 err = setup_rt_frame(sig, ka, info, oldset, regs); 1135 else 1136 err = setup_frame(sig, ka, oldset, regs); 1137 1138 if (err) 1139 return; 1140 1141 signal_delivered(sig, info, ka, regs, 0); 1142 1143 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1144 regs->sr &= ~0x8000; 1145 send_sig(SIGTRAP, current, 1); 1146 } 1147 } 1148 1149 /* 1150 * Note that 'init' is a special process: it doesn't get signals it doesn't 1151 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1152 * mistake. 1153 */ 1154 static void do_signal(struct pt_regs *regs) 1155 { 1156 siginfo_t info; 1157 struct k_sigaction ka; 1158 int signr; 1159 1160 current->thread.esp0 = (unsigned long) regs; 1161 1162 signr = get_signal_to_deliver(&info, &ka, regs, NULL); 1163 if (signr > 0) { 1164 /* Whee! Actually deliver the signal. */ 1165 handle_signal(signr, &ka, &info, regs); 1166 return; 1167 } 1168 1169 /* Did we come from a system call? */ 1170 if (regs->orig_d0 >= 0) 1171 /* Restart the system call - no handlers present */ 1172 handle_restart(regs, NULL, 0); 1173 1174 /* If there's no signal to deliver, we just restore the saved mask. */ 1175 restore_saved_sigmask(); 1176 } 1177 1178 void do_notify_resume(struct pt_regs *regs) 1179 { 1180 if (test_thread_flag(TIF_SIGPENDING)) 1181 do_signal(regs); 1182 1183 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) 1184 tracehook_notify_resume(regs); 1185 } 1186