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