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 void ptrace_signal_deliver(void) 113 { 114 struct pt_regs *regs = signal_pt_regs(); 115 if (regs->orig_d0 < 0) 116 return; 117 switch (regs->d0) { 118 case -ERESTARTNOHAND: 119 case -ERESTARTSYS: 120 case -ERESTARTNOINTR: 121 regs->d0 = regs->orig_d0; 122 regs->orig_d0 = -1; 123 regs->pc -= 2; 124 break; 125 } 126 } 127 128 static inline void push_cache (unsigned long vaddr) 129 { 130 /* 131 * Using the old cache_push_v() was really a big waste. 132 * 133 * What we are trying to do is to flush 8 bytes to ram. 134 * Flushing 2 cache lines of 16 bytes is much cheaper than 135 * flushing 1 or 2 pages, as previously done in 136 * cache_push_v(). 137 * Jes 138 */ 139 if (CPU_IS_040) { 140 unsigned long temp; 141 142 __asm__ __volatile__ (".chip 68040\n\t" 143 "nop\n\t" 144 "ptestr (%1)\n\t" 145 "movec %%mmusr,%0\n\t" 146 ".chip 68k" 147 : "=r" (temp) 148 : "a" (vaddr)); 149 150 temp &= PAGE_MASK; 151 temp |= vaddr & ~PAGE_MASK; 152 153 __asm__ __volatile__ (".chip 68040\n\t" 154 "nop\n\t" 155 "cpushl %%bc,(%0)\n\t" 156 ".chip 68k" 157 : : "a" (temp)); 158 } 159 else if (CPU_IS_060) { 160 unsigned long temp; 161 __asm__ __volatile__ (".chip 68060\n\t" 162 "plpar (%0)\n\t" 163 ".chip 68k" 164 : "=a" (temp) 165 : "0" (vaddr)); 166 __asm__ __volatile__ (".chip 68060\n\t" 167 "cpushl %%bc,(%0)\n\t" 168 ".chip 68k" 169 : : "a" (temp)); 170 } else if (!CPU_IS_COLDFIRE) { 171 /* 172 * 68030/68020 have no writeback cache; 173 * still need to clear icache. 174 * Note that vaddr is guaranteed to be long word aligned. 175 */ 176 unsigned long temp; 177 asm volatile ("movec %%cacr,%0" : "=r" (temp)); 178 temp += 4; 179 asm volatile ("movec %0,%%caar\n\t" 180 "movec %1,%%cacr" 181 : : "r" (vaddr), "r" (temp)); 182 asm volatile ("movec %0,%%caar\n\t" 183 "movec %1,%%cacr" 184 : : "r" (vaddr + 4), "r" (temp)); 185 } else { 186 /* CPU_IS_COLDFIRE */ 187 #if defined(CONFIG_CACHE_COPYBACK) 188 flush_cf_dcache(0, DCACHE_MAX_ADDR); 189 #endif 190 /* Invalidate instruction cache for the pushed bytes */ 191 clear_cf_icache(vaddr, vaddr + 8); 192 } 193 } 194 195 static inline void adjustformat(struct pt_regs *regs) 196 { 197 } 198 199 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 200 { 201 } 202 203 #else /* CONFIG_MMU */ 204 205 void ret_from_user_signal(void); 206 void ret_from_user_rt_signal(void); 207 208 static inline int frame_extra_sizes(int f) 209 { 210 /* No frame size adjustments required on non-MMU CPUs */ 211 return 0; 212 } 213 214 static inline void adjustformat(struct pt_regs *regs) 215 { 216 /* 217 * set format byte to make stack appear modulo 4, which it will 218 * be when doing the rte 219 */ 220 regs->format = 0x4; 221 } 222 223 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 224 { 225 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5; 226 } 227 228 static inline void push_cache(unsigned long vaddr) 229 { 230 } 231 232 #endif /* CONFIG_MMU */ 233 234 /* 235 * Do a signal return; undo the signal stack. 236 * 237 * Keep the return code on the stack quadword aligned! 238 * That makes the cache flush below easier. 239 */ 240 241 struct sigframe 242 { 243 char __user *pretcode; 244 int sig; 245 int code; 246 struct sigcontext __user *psc; 247 char retcode[8]; 248 unsigned long extramask[_NSIG_WORDS-1]; 249 struct sigcontext sc; 250 }; 251 252 struct rt_sigframe 253 { 254 char __user *pretcode; 255 int sig; 256 struct siginfo __user *pinfo; 257 void __user *puc; 258 char retcode[8]; 259 struct siginfo info; 260 struct ucontext uc; 261 }; 262 263 #define FPCONTEXT_SIZE 216 264 #define uc_fpstate uc_filler[0] 265 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] 266 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] 267 268 #ifdef CONFIG_FPU 269 270 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ 271 272 static inline int restore_fpu_state(struct sigcontext *sc) 273 { 274 int err = 1; 275 276 if (FPU_IS_EMU) { 277 /* restore registers */ 278 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); 279 memcpy(current->thread.fp, sc->sc_fpregs, 24); 280 return 0; 281 } 282 283 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 284 /* Verify the frame format. */ 285 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 286 (sc->sc_fpstate[0] != fpu_version)) 287 goto out; 288 if (CPU_IS_020_OR_030) { 289 if (m68k_fputype & FPU_68881 && 290 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) 291 goto out; 292 if (m68k_fputype & FPU_68882 && 293 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) 294 goto out; 295 } else if (CPU_IS_040) { 296 if (!(sc->sc_fpstate[1] == 0x00 || 297 sc->sc_fpstate[1] == 0x28 || 298 sc->sc_fpstate[1] == 0x60)) 299 goto out; 300 } else if (CPU_IS_060) { 301 if (!(sc->sc_fpstate[3] == 0x00 || 302 sc->sc_fpstate[3] == 0x60 || 303 sc->sc_fpstate[3] == 0xe0)) 304 goto out; 305 } else if (CPU_IS_COLDFIRE) { 306 if (!(sc->sc_fpstate[0] == 0x00 || 307 sc->sc_fpstate[0] == 0x05 || 308 sc->sc_fpstate[0] == 0xe5)) 309 goto out; 310 } else 311 goto out; 312 313 if (CPU_IS_COLDFIRE) { 314 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t" 315 "fmovel %1,%%fpcr\n\t" 316 "fmovel %2,%%fpsr\n\t" 317 "fmovel %3,%%fpiar" 318 : /* no outputs */ 319 : "m" (sc->sc_fpregs[0]), 320 "m" (sc->sc_fpcntl[0]), 321 "m" (sc->sc_fpcntl[1]), 322 "m" (sc->sc_fpcntl[2])); 323 } else { 324 __asm__ volatile (".chip 68k/68881\n\t" 325 "fmovemx %0,%%fp0-%%fp1\n\t" 326 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 327 ".chip 68k" 328 : /* no outputs */ 329 : "m" (*sc->sc_fpregs), 330 "m" (*sc->sc_fpcntl)); 331 } 332 } 333 334 if (CPU_IS_COLDFIRE) { 335 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate)); 336 } else { 337 __asm__ volatile (".chip 68k/68881\n\t" 338 "frestore %0\n\t" 339 ".chip 68k" 340 : : "m" (*sc->sc_fpstate)); 341 } 342 err = 0; 343 344 out: 345 return err; 346 } 347 348 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 349 { 350 unsigned char fpstate[FPCONTEXT_SIZE]; 351 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 352 fpregset_t fpregs; 353 int err = 1; 354 355 if (FPU_IS_EMU) { 356 /* restore fpu control register */ 357 if (__copy_from_user(current->thread.fpcntl, 358 uc->uc_mcontext.fpregs.f_fpcntl, 12)) 359 goto out; 360 /* restore all other fpu register */ 361 if (__copy_from_user(current->thread.fp, 362 uc->uc_mcontext.fpregs.f_fpregs, 96)) 363 goto out; 364 return 0; 365 } 366 367 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate)) 368 goto out; 369 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 370 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 371 context_size = fpstate[1]; 372 /* Verify the frame format. */ 373 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 374 (fpstate[0] != fpu_version)) 375 goto out; 376 if (CPU_IS_020_OR_030) { 377 if (m68k_fputype & FPU_68881 && 378 !(context_size == 0x18 || context_size == 0xb4)) 379 goto out; 380 if (m68k_fputype & FPU_68882 && 381 !(context_size == 0x38 || context_size == 0xd4)) 382 goto out; 383 } else if (CPU_IS_040) { 384 if (!(context_size == 0x00 || 385 context_size == 0x28 || 386 context_size == 0x60)) 387 goto out; 388 } else if (CPU_IS_060) { 389 if (!(fpstate[3] == 0x00 || 390 fpstate[3] == 0x60 || 391 fpstate[3] == 0xe0)) 392 goto out; 393 } else if (CPU_IS_COLDFIRE) { 394 if (!(fpstate[3] == 0x00 || 395 fpstate[3] == 0x05 || 396 fpstate[3] == 0xe5)) 397 goto out; 398 } else 399 goto out; 400 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, 401 sizeof(fpregs))) 402 goto out; 403 404 if (CPU_IS_COLDFIRE) { 405 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t" 406 "fmovel %1,%%fpcr\n\t" 407 "fmovel %2,%%fpsr\n\t" 408 "fmovel %3,%%fpiar" 409 : /* no outputs */ 410 : "m" (fpregs.f_fpregs[0]), 411 "m" (fpregs.f_fpcntl[0]), 412 "m" (fpregs.f_fpcntl[1]), 413 "m" (fpregs.f_fpcntl[2])); 414 } else { 415 __asm__ volatile (".chip 68k/68881\n\t" 416 "fmovemx %0,%%fp0-%%fp7\n\t" 417 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 418 ".chip 68k" 419 : /* no outputs */ 420 : "m" (*fpregs.f_fpregs), 421 "m" (*fpregs.f_fpcntl)); 422 } 423 } 424 if (context_size && 425 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1, 426 context_size)) 427 goto out; 428 429 if (CPU_IS_COLDFIRE) { 430 __asm__ volatile ("frestore %0" : : "m" (*fpstate)); 431 } else { 432 __asm__ volatile (".chip 68k/68881\n\t" 433 "frestore %0\n\t" 434 ".chip 68k" 435 : : "m" (*fpstate)); 436 } 437 err = 0; 438 439 out: 440 return err; 441 } 442 443 /* 444 * Set up a signal frame. 445 */ 446 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 447 { 448 if (FPU_IS_EMU) { 449 /* save registers */ 450 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); 451 memcpy(sc->sc_fpregs, current->thread.fp, 24); 452 return; 453 } 454 455 if (CPU_IS_COLDFIRE) { 456 __asm__ volatile ("fsave %0" 457 : : "m" (*sc->sc_fpstate) : "memory"); 458 } else { 459 __asm__ volatile (".chip 68k/68881\n\t" 460 "fsave %0\n\t" 461 ".chip 68k" 462 : : "m" (*sc->sc_fpstate) : "memory"); 463 } 464 465 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 466 fpu_version = sc->sc_fpstate[0]; 467 if (CPU_IS_020_OR_030 && 468 regs->vector >= (VEC_FPBRUC * 4) && 469 regs->vector <= (VEC_FPNAN * 4)) { 470 /* Clear pending exception in 68882 idle frame */ 471 if (*(unsigned short *) sc->sc_fpstate == 0x1f38) 472 sc->sc_fpstate[0x38] |= 1 << 3; 473 } 474 475 if (CPU_IS_COLDFIRE) { 476 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t" 477 "fmovel %%fpcr,%1\n\t" 478 "fmovel %%fpsr,%2\n\t" 479 "fmovel %%fpiar,%3" 480 : "=m" (sc->sc_fpregs[0]), 481 "=m" (sc->sc_fpcntl[0]), 482 "=m" (sc->sc_fpcntl[1]), 483 "=m" (sc->sc_fpcntl[2]) 484 : /* no inputs */ 485 : "memory"); 486 } else { 487 __asm__ volatile (".chip 68k/68881\n\t" 488 "fmovemx %%fp0-%%fp1,%0\n\t" 489 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 490 ".chip 68k" 491 : "=m" (*sc->sc_fpregs), 492 "=m" (*sc->sc_fpcntl) 493 : /* no inputs */ 494 : "memory"); 495 } 496 } 497 } 498 499 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 500 { 501 unsigned char fpstate[FPCONTEXT_SIZE]; 502 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 503 int err = 0; 504 505 if (FPU_IS_EMU) { 506 /* save fpu control register */ 507 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, 508 current->thread.fpcntl, 12); 509 /* save all other fpu register */ 510 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, 511 current->thread.fp, 96); 512 return err; 513 } 514 515 if (CPU_IS_COLDFIRE) { 516 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory"); 517 } else { 518 __asm__ volatile (".chip 68k/68881\n\t" 519 "fsave %0\n\t" 520 ".chip 68k" 521 : : "m" (*fpstate) : "memory"); 522 } 523 524 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate); 525 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 526 fpregset_t fpregs; 527 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 528 context_size = fpstate[1]; 529 fpu_version = fpstate[0]; 530 if (CPU_IS_020_OR_030 && 531 regs->vector >= (VEC_FPBRUC * 4) && 532 regs->vector <= (VEC_FPNAN * 4)) { 533 /* Clear pending exception in 68882 idle frame */ 534 if (*(unsigned short *) fpstate == 0x1f38) 535 fpstate[0x38] |= 1 << 3; 536 } 537 if (CPU_IS_COLDFIRE) { 538 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t" 539 "fmovel %%fpcr,%1\n\t" 540 "fmovel %%fpsr,%2\n\t" 541 "fmovel %%fpiar,%3" 542 : "=m" (fpregs.f_fpregs[0]), 543 "=m" (fpregs.f_fpcntl[0]), 544 "=m" (fpregs.f_fpcntl[1]), 545 "=m" (fpregs.f_fpcntl[2]) 546 : /* no inputs */ 547 : "memory"); 548 } else { 549 __asm__ volatile (".chip 68k/68881\n\t" 550 "fmovemx %%fp0-%%fp7,%0\n\t" 551 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 552 ".chip 68k" 553 : "=m" (*fpregs.f_fpregs), 554 "=m" (*fpregs.f_fpcntl) 555 : /* no inputs */ 556 : "memory"); 557 } 558 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, 559 sizeof(fpregs)); 560 } 561 if (context_size) 562 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4, 563 context_size); 564 return err; 565 } 566 567 #else /* CONFIG_FPU */ 568 569 /* 570 * For the case with no FPU configured these all do nothing. 571 */ 572 static inline int restore_fpu_state(struct sigcontext *sc) 573 { 574 return 0; 575 } 576 577 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 578 { 579 return 0; 580 } 581 582 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 583 { 584 } 585 586 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 587 { 588 return 0; 589 } 590 591 #endif /* CONFIG_FPU */ 592 593 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, 594 void __user *fp) 595 { 596 int fsize = frame_extra_sizes(formatvec >> 12); 597 if (fsize < 0) { 598 /* 599 * user process trying to return with weird frame format 600 */ 601 pr_debug("user process returning with weird frame format\n"); 602 return 1; 603 } 604 if (!fsize) { 605 regs->format = formatvec >> 12; 606 regs->vector = formatvec & 0xfff; 607 } else { 608 struct switch_stack *sw = (struct switch_stack *)regs - 1; 609 unsigned long buf[fsize / 2]; /* yes, twice as much */ 610 611 /* that'll make sure that expansion won't crap over data */ 612 if (copy_from_user(buf + fsize / 4, fp, fsize)) 613 return 1; 614 615 /* point of no return */ 616 regs->format = formatvec >> 12; 617 regs->vector = formatvec & 0xfff; 618 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) 619 __asm__ __volatile__ ( 620 #ifdef CONFIG_COLDFIRE 621 " movel %0,%/sp\n\t" 622 " bra ret_from_signal\n" 623 #else 624 " movel %0,%/a0\n\t" 625 " subl %1,%/a0\n\t" /* make room on stack */ 626 " movel %/a0,%/sp\n\t" /* set stack pointer */ 627 /* move switch_stack and pt_regs */ 628 "1: movel %0@+,%/a0@+\n\t" 629 " dbra %2,1b\n\t" 630 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ 631 " lsrl #2,%1\n\t" 632 " subql #1,%1\n\t" 633 /* copy to the gap we'd made */ 634 "2: movel %4@+,%/a0@+\n\t" 635 " dbra %1,2b\n\t" 636 " bral ret_from_signal\n" 637 #endif 638 : /* no outputs, it doesn't ever return */ 639 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), 640 "n" (frame_offset), "a" (buf + fsize/4) 641 : "a0"); 642 #undef frame_offset 643 } 644 return 0; 645 } 646 647 static inline int 648 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) 649 { 650 int formatvec; 651 struct sigcontext context; 652 int err = 0; 653 654 /* Always make any pending restarted system calls return -EINTR */ 655 current->restart_block.fn = do_no_restart_syscall; 656 657 /* get previous context */ 658 if (copy_from_user(&context, usc, sizeof(context))) 659 goto badframe; 660 661 /* restore passed registers */ 662 regs->d0 = context.sc_d0; 663 regs->d1 = context.sc_d1; 664 regs->a0 = context.sc_a0; 665 regs->a1 = context.sc_a1; 666 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); 667 regs->pc = context.sc_pc; 668 regs->orig_d0 = -1; /* disable syscall checks */ 669 wrusp(context.sc_usp); 670 formatvec = context.sc_formatvec; 671 672 err = restore_fpu_state(&context); 673 674 if (err || mangle_kernel_stack(regs, formatvec, fp)) 675 goto badframe; 676 677 return 0; 678 679 badframe: 680 return 1; 681 } 682 683 static inline int 684 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, 685 struct ucontext __user *uc) 686 { 687 int temp; 688 greg_t __user *gregs = uc->uc_mcontext.gregs; 689 unsigned long usp; 690 int err; 691 692 /* Always make any pending restarted system calls return -EINTR */ 693 current->restart_block.fn = do_no_restart_syscall; 694 695 err = __get_user(temp, &uc->uc_mcontext.version); 696 if (temp != MCONTEXT_VERSION) 697 goto badframe; 698 /* restore passed registers */ 699 err |= __get_user(regs->d0, &gregs[0]); 700 err |= __get_user(regs->d1, &gregs[1]); 701 err |= __get_user(regs->d2, &gregs[2]); 702 err |= __get_user(regs->d3, &gregs[3]); 703 err |= __get_user(regs->d4, &gregs[4]); 704 err |= __get_user(regs->d5, &gregs[5]); 705 err |= __get_user(sw->d6, &gregs[6]); 706 err |= __get_user(sw->d7, &gregs[7]); 707 err |= __get_user(regs->a0, &gregs[8]); 708 err |= __get_user(regs->a1, &gregs[9]); 709 err |= __get_user(regs->a2, &gregs[10]); 710 err |= __get_user(sw->a3, &gregs[11]); 711 err |= __get_user(sw->a4, &gregs[12]); 712 err |= __get_user(sw->a5, &gregs[13]); 713 err |= __get_user(sw->a6, &gregs[14]); 714 err |= __get_user(usp, &gregs[15]); 715 wrusp(usp); 716 err |= __get_user(regs->pc, &gregs[16]); 717 err |= __get_user(temp, &gregs[17]); 718 regs->sr = (regs->sr & 0xff00) | (temp & 0xff); 719 regs->orig_d0 = -1; /* disable syscall checks */ 720 err |= __get_user(temp, &uc->uc_formatvec); 721 722 err |= rt_restore_fpu_state(uc); 723 err |= restore_altstack(&uc->uc_stack); 724 725 if (err) 726 goto badframe; 727 728 if (mangle_kernel_stack(regs, temp, &uc->uc_extra)) 729 goto badframe; 730 731 return 0; 732 733 badframe: 734 return 1; 735 } 736 737 asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 738 { 739 unsigned long usp = rdusp(); 740 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 741 sigset_t set; 742 743 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 744 goto badframe; 745 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 746 (_NSIG_WORDS > 1 && 747 __copy_from_user(&set.sig[1], &frame->extramask, 748 sizeof(frame->extramask)))) 749 goto badframe; 750 751 set_current_blocked(&set); 752 753 if (restore_sigcontext(regs, &frame->sc, frame + 1)) 754 goto badframe; 755 return regs->d0; 756 757 badframe: 758 force_sig(SIGSEGV, current); 759 return 0; 760 } 761 762 asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 763 { 764 unsigned long usp = rdusp(); 765 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 766 sigset_t set; 767 768 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 769 goto badframe; 770 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 771 goto badframe; 772 773 set_current_blocked(&set); 774 775 if (rt_restore_ucontext(regs, sw, &frame->uc)) 776 goto badframe; 777 return regs->d0; 778 779 badframe: 780 force_sig(SIGSEGV, current); 781 return 0; 782 } 783 784 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 785 unsigned long mask) 786 { 787 sc->sc_mask = mask; 788 sc->sc_usp = rdusp(); 789 sc->sc_d0 = regs->d0; 790 sc->sc_d1 = regs->d1; 791 sc->sc_a0 = regs->a0; 792 sc->sc_a1 = regs->a1; 793 sc->sc_sr = regs->sr; 794 sc->sc_pc = regs->pc; 795 sc->sc_formatvec = regs->format << 12 | regs->vector; 796 save_a5_state(sc, regs); 797 save_fpu_state(sc, regs); 798 } 799 800 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 801 { 802 struct switch_stack *sw = (struct switch_stack *)regs - 1; 803 greg_t __user *gregs = uc->uc_mcontext.gregs; 804 int err = 0; 805 806 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 807 err |= __put_user(regs->d0, &gregs[0]); 808 err |= __put_user(regs->d1, &gregs[1]); 809 err |= __put_user(regs->d2, &gregs[2]); 810 err |= __put_user(regs->d3, &gregs[3]); 811 err |= __put_user(regs->d4, &gregs[4]); 812 err |= __put_user(regs->d5, &gregs[5]); 813 err |= __put_user(sw->d6, &gregs[6]); 814 err |= __put_user(sw->d7, &gregs[7]); 815 err |= __put_user(regs->a0, &gregs[8]); 816 err |= __put_user(regs->a1, &gregs[9]); 817 err |= __put_user(regs->a2, &gregs[10]); 818 err |= __put_user(sw->a3, &gregs[11]); 819 err |= __put_user(sw->a4, &gregs[12]); 820 err |= __put_user(sw->a5, &gregs[13]); 821 err |= __put_user(sw->a6, &gregs[14]); 822 err |= __put_user(rdusp(), &gregs[15]); 823 err |= __put_user(regs->pc, &gregs[16]); 824 err |= __put_user(regs->sr, &gregs[17]); 825 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); 826 err |= rt_save_fpu_state(uc, regs); 827 return err; 828 } 829 830 static inline void __user * 831 get_sigframe(struct ksignal *ksig, size_t frame_size) 832 { 833 unsigned long usp = sigsp(rdusp(), ksig); 834 835 return (void __user *)((usp - frame_size) & -8UL); 836 } 837 838 static int setup_frame(struct ksignal *ksig, sigset_t *set, 839 struct pt_regs *regs) 840 { 841 struct sigframe __user *frame; 842 int fsize = frame_extra_sizes(regs->format); 843 struct sigcontext context; 844 int err = 0, sig = ksig->sig; 845 846 if (fsize < 0) { 847 pr_debug("setup_frame: Unknown frame format %#x\n", 848 regs->format); 849 return -EFAULT; 850 } 851 852 frame = get_sigframe(ksig, sizeof(*frame) + fsize); 853 854 if (fsize) 855 err |= copy_to_user (frame + 1, regs + 1, fsize); 856 857 err |= __put_user(sig, &frame->sig); 858 859 err |= __put_user(regs->vector, &frame->code); 860 err |= __put_user(&frame->sc, &frame->psc); 861 862 if (_NSIG_WORDS > 1) 863 err |= copy_to_user(frame->extramask, &set->sig[1], 864 sizeof(frame->extramask)); 865 866 setup_sigcontext(&context, regs, set->sig[0]); 867 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 868 869 /* Set up to return from userspace. */ 870 #ifdef CONFIG_MMU 871 err |= __put_user(frame->retcode, &frame->pretcode); 872 /* moveq #,d0; trap #0 */ 873 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 874 (long __user *)(frame->retcode)); 875 #else 876 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode); 877 #endif 878 879 if (err) 880 return -EFAULT; 881 882 push_cache ((unsigned long) &frame->retcode); 883 884 /* 885 * Set up registers for signal handler. All the state we are about 886 * to destroy is successfully copied to sigframe. 887 */ 888 wrusp ((unsigned long) frame); 889 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 890 adjustformat(regs); 891 892 /* 893 * This is subtle; if we build more than one sigframe, all but the 894 * first one will see frame format 0 and have fsize == 0, so we won't 895 * screw stkadj. 896 */ 897 if (fsize) 898 regs->stkadj = fsize; 899 900 /* Prepare to skip over the extra stuff in the exception frame. */ 901 if (regs->stkadj) { 902 struct pt_regs *tregs = 903 (struct pt_regs *)((ulong)regs + regs->stkadj); 904 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 905 /* This must be copied with decreasing addresses to 906 handle overlaps. */ 907 tregs->vector = 0; 908 tregs->format = 0; 909 tregs->pc = regs->pc; 910 tregs->sr = regs->sr; 911 } 912 return 0; 913 } 914 915 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, 916 struct pt_regs *regs) 917 { 918 struct rt_sigframe __user *frame; 919 int fsize = frame_extra_sizes(regs->format); 920 int err = 0, sig = ksig->sig; 921 922 if (fsize < 0) { 923 pr_debug("setup_frame: Unknown frame format %#x\n", 924 regs->format); 925 return -EFAULT; 926 } 927 928 frame = get_sigframe(ksig, sizeof(*frame)); 929 930 if (fsize) 931 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 932 933 err |= __put_user(sig, &frame->sig); 934 err |= __put_user(&frame->info, &frame->pinfo); 935 err |= __put_user(&frame->uc, &frame->puc); 936 err |= copy_siginfo_to_user(&frame->info, &ksig->info); 937 938 /* Create the ucontext. */ 939 err |= __put_user(0, &frame->uc.uc_flags); 940 err |= __put_user(NULL, &frame->uc.uc_link); 941 err |= __save_altstack(&frame->uc.uc_stack, rdusp()); 942 err |= rt_setup_ucontext(&frame->uc, regs); 943 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 944 945 /* Set up to return from userspace. */ 946 #ifdef CONFIG_MMU 947 err |= __put_user(frame->retcode, &frame->pretcode); 948 #ifdef __mcoldfire__ 949 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 950 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 951 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 952 (long __user *)(frame->retcode + 4)); 953 #else 954 /* moveq #,d0; notb d0; trap #0 */ 955 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 956 (long __user *)(frame->retcode + 0)); 957 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 958 #endif 959 #else 960 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode); 961 #endif /* CONFIG_MMU */ 962 963 if (err) 964 return -EFAULT; 965 966 push_cache ((unsigned long) &frame->retcode); 967 968 /* 969 * Set up registers for signal handler. All the state we are about 970 * to destroy is successfully copied to sigframe. 971 */ 972 wrusp ((unsigned long) frame); 973 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 974 adjustformat(regs); 975 976 /* 977 * This is subtle; if we build more than one sigframe, all but the 978 * first one will see frame format 0 and have fsize == 0, so we won't 979 * screw stkadj. 980 */ 981 if (fsize) 982 regs->stkadj = fsize; 983 984 /* Prepare to skip over the extra stuff in the exception frame. */ 985 if (regs->stkadj) { 986 struct pt_regs *tregs = 987 (struct pt_regs *)((ulong)regs + regs->stkadj); 988 pr_debug("Performing stackadjust=%04lx\n", regs->stkadj); 989 /* This must be copied with decreasing addresses to 990 handle overlaps. */ 991 tregs->vector = 0; 992 tregs->format = 0; 993 tregs->pc = regs->pc; 994 tregs->sr = regs->sr; 995 } 996 return 0; 997 } 998 999 static inline void 1000 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1001 { 1002 switch (regs->d0) { 1003 case -ERESTARTNOHAND: 1004 if (!has_handler) 1005 goto do_restart; 1006 regs->d0 = -EINTR; 1007 break; 1008 1009 case -ERESTART_RESTARTBLOCK: 1010 if (!has_handler) { 1011 regs->d0 = __NR_restart_syscall; 1012 regs->pc -= 2; 1013 break; 1014 } 1015 regs->d0 = -EINTR; 1016 break; 1017 1018 case -ERESTARTSYS: 1019 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1020 regs->d0 = -EINTR; 1021 break; 1022 } 1023 /* fallthrough */ 1024 case -ERESTARTNOINTR: 1025 do_restart: 1026 regs->d0 = regs->orig_d0; 1027 regs->pc -= 2; 1028 break; 1029 } 1030 } 1031 1032 /* 1033 * OK, we're invoking a handler 1034 */ 1035 static void 1036 handle_signal(struct ksignal *ksig, struct pt_regs *regs) 1037 { 1038 sigset_t *oldset = sigmask_to_save(); 1039 int err; 1040 /* are we from a system call? */ 1041 if (regs->orig_d0 >= 0) 1042 /* If so, check system call restarting.. */ 1043 handle_restart(regs, &ksig->ka, 1); 1044 1045 /* set up the stack frame */ 1046 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 1047 err = setup_rt_frame(ksig, oldset, regs); 1048 else 1049 err = setup_frame(ksig, oldset, regs); 1050 1051 signal_setup_done(err, ksig, 0); 1052 1053 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1054 regs->sr &= ~0x8000; 1055 send_sig(SIGTRAP, current, 1); 1056 } 1057 } 1058 1059 /* 1060 * Note that 'init' is a special process: it doesn't get signals it doesn't 1061 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1062 * mistake. 1063 */ 1064 static void do_signal(struct pt_regs *regs) 1065 { 1066 struct ksignal ksig; 1067 1068 current->thread.esp0 = (unsigned long) regs; 1069 1070 if (get_signal(&ksig)) { 1071 /* Whee! Actually deliver the signal. */ 1072 handle_signal(&ksig, regs); 1073 return; 1074 } 1075 1076 /* Did we come from a system call? */ 1077 if (regs->orig_d0 >= 0) 1078 /* Restart the system call - no handlers present */ 1079 handle_restart(regs, NULL, 0); 1080 1081 /* If there's no signal to deliver, we just restore the saved mask. */ 1082 restore_saved_sigmask(); 1083 } 1084 1085 void do_notify_resume(struct pt_regs *regs) 1086 { 1087 if (test_thread_flag(TIF_SIGPENDING)) 1088 do_signal(regs); 1089 1090 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) 1091 tracehook_notify_resume(regs); 1092 } 1093