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 #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 handle_kernel_fault(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 ((struct switch_stack *)regs - 1)->a5 = current->mm->start_data; 217 /* 218 * set format byte to make stack appear modulo 4, which it will 219 * be when doing the rte 220 */ 221 regs->format = 0x4; 222 } 223 224 static inline void save_a5_state(struct sigcontext *sc, struct pt_regs *regs) 225 { 226 sc->sc_a5 = ((struct switch_stack *)regs - 1)->a5; 227 } 228 229 static inline void push_cache(unsigned long vaddr) 230 { 231 } 232 233 #endif /* CONFIG_MMU */ 234 235 /* 236 * Do a signal return; undo the signal stack. 237 * 238 * Keep the return code on the stack quadword aligned! 239 * That makes the cache flush below easier. 240 */ 241 242 struct sigframe 243 { 244 char __user *pretcode; 245 int sig; 246 int code; 247 struct sigcontext __user *psc; 248 char retcode[8]; 249 unsigned long extramask[_NSIG_WORDS-1]; 250 struct sigcontext sc; 251 }; 252 253 struct rt_sigframe 254 { 255 char __user *pretcode; 256 int sig; 257 struct siginfo __user *pinfo; 258 void __user *puc; 259 char retcode[8]; 260 struct siginfo info; 261 struct ucontext uc; 262 }; 263 264 #define FPCONTEXT_SIZE 216 265 #define uc_fpstate uc_filler[0] 266 #define uc_formatvec uc_filler[FPCONTEXT_SIZE/4] 267 #define uc_extra uc_filler[FPCONTEXT_SIZE/4+1] 268 269 #ifdef CONFIG_FPU 270 271 static unsigned char fpu_version; /* version number of fpu, set by setup_frame */ 272 273 static inline int restore_fpu_state(struct sigcontext *sc) 274 { 275 int err = 1; 276 277 if (FPU_IS_EMU) { 278 /* restore registers */ 279 memcpy(current->thread.fpcntl, sc->sc_fpcntl, 12); 280 memcpy(current->thread.fp, sc->sc_fpregs, 24); 281 return 0; 282 } 283 284 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 285 /* Verify the frame format. */ 286 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 287 (sc->sc_fpstate[0] != fpu_version)) 288 goto out; 289 if (CPU_IS_020_OR_030) { 290 if (m68k_fputype & FPU_68881 && 291 !(sc->sc_fpstate[1] == 0x18 || sc->sc_fpstate[1] == 0xb4)) 292 goto out; 293 if (m68k_fputype & FPU_68882 && 294 !(sc->sc_fpstate[1] == 0x38 || sc->sc_fpstate[1] == 0xd4)) 295 goto out; 296 } else if (CPU_IS_040) { 297 if (!(sc->sc_fpstate[1] == 0x00 || 298 sc->sc_fpstate[1] == 0x28 || 299 sc->sc_fpstate[1] == 0x60)) 300 goto out; 301 } else if (CPU_IS_060) { 302 if (!(sc->sc_fpstate[3] == 0x00 || 303 sc->sc_fpstate[3] == 0x60 || 304 sc->sc_fpstate[3] == 0xe0)) 305 goto out; 306 } else if (CPU_IS_COLDFIRE) { 307 if (!(sc->sc_fpstate[0] == 0x00 || 308 sc->sc_fpstate[0] == 0x05 || 309 sc->sc_fpstate[0] == 0xe5)) 310 goto out; 311 } else 312 goto out; 313 314 if (CPU_IS_COLDFIRE) { 315 __asm__ volatile ("fmovemd %0,%%fp0-%%fp1\n\t" 316 "fmovel %1,%%fpcr\n\t" 317 "fmovel %2,%%fpsr\n\t" 318 "fmovel %3,%%fpiar" 319 : /* no outputs */ 320 : "m" (sc->sc_fpregs[0]), 321 "m" (sc->sc_fpcntl[0]), 322 "m" (sc->sc_fpcntl[1]), 323 "m" (sc->sc_fpcntl[2])); 324 } else { 325 __asm__ volatile (".chip 68k/68881\n\t" 326 "fmovemx %0,%%fp0-%%fp1\n\t" 327 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 328 ".chip 68k" 329 : /* no outputs */ 330 : "m" (*sc->sc_fpregs), 331 "m" (*sc->sc_fpcntl)); 332 } 333 } 334 335 if (CPU_IS_COLDFIRE) { 336 __asm__ volatile ("frestore %0" : : "m" (*sc->sc_fpstate)); 337 } else { 338 __asm__ volatile (".chip 68k/68881\n\t" 339 "frestore %0\n\t" 340 ".chip 68k" 341 : : "m" (*sc->sc_fpstate)); 342 } 343 err = 0; 344 345 out: 346 return err; 347 } 348 349 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 350 { 351 unsigned char fpstate[FPCONTEXT_SIZE]; 352 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 353 fpregset_t fpregs; 354 int err = 1; 355 356 if (FPU_IS_EMU) { 357 /* restore fpu control register */ 358 if (__copy_from_user(current->thread.fpcntl, 359 uc->uc_mcontext.fpregs.f_fpcntl, 12)) 360 goto out; 361 /* restore all other fpu register */ 362 if (__copy_from_user(current->thread.fp, 363 uc->uc_mcontext.fpregs.f_fpregs, 96)) 364 goto out; 365 return 0; 366 } 367 368 if (__get_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate)) 369 goto out; 370 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 371 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 372 context_size = fpstate[1]; 373 /* Verify the frame format. */ 374 if (!(CPU_IS_060 || CPU_IS_COLDFIRE) && 375 (fpstate[0] != fpu_version)) 376 goto out; 377 if (CPU_IS_020_OR_030) { 378 if (m68k_fputype & FPU_68881 && 379 !(context_size == 0x18 || context_size == 0xb4)) 380 goto out; 381 if (m68k_fputype & FPU_68882 && 382 !(context_size == 0x38 || context_size == 0xd4)) 383 goto out; 384 } else if (CPU_IS_040) { 385 if (!(context_size == 0x00 || 386 context_size == 0x28 || 387 context_size == 0x60)) 388 goto out; 389 } else if (CPU_IS_060) { 390 if (!(fpstate[3] == 0x00 || 391 fpstate[3] == 0x60 || 392 fpstate[3] == 0xe0)) 393 goto out; 394 } else if (CPU_IS_COLDFIRE) { 395 if (!(fpstate[3] == 0x00 || 396 fpstate[3] == 0x05 || 397 fpstate[3] == 0xe5)) 398 goto out; 399 } else 400 goto out; 401 if (__copy_from_user(&fpregs, &uc->uc_mcontext.fpregs, 402 sizeof(fpregs))) 403 goto out; 404 405 if (CPU_IS_COLDFIRE) { 406 __asm__ volatile ("fmovemd %0,%%fp0-%%fp7\n\t" 407 "fmovel %1,%%fpcr\n\t" 408 "fmovel %2,%%fpsr\n\t" 409 "fmovel %3,%%fpiar" 410 : /* no outputs */ 411 : "m" (fpregs.f_fpregs[0]), 412 "m" (fpregs.f_fpcntl[0]), 413 "m" (fpregs.f_fpcntl[1]), 414 "m" (fpregs.f_fpcntl[2])); 415 } else { 416 __asm__ volatile (".chip 68k/68881\n\t" 417 "fmovemx %0,%%fp0-%%fp7\n\t" 418 "fmoveml %1,%%fpcr/%%fpsr/%%fpiar\n\t" 419 ".chip 68k" 420 : /* no outputs */ 421 : "m" (*fpregs.f_fpregs), 422 "m" (*fpregs.f_fpcntl)); 423 } 424 } 425 if (context_size && 426 __copy_from_user(fpstate + 4, (long __user *)&uc->uc_fpstate + 1, 427 context_size)) 428 goto out; 429 430 if (CPU_IS_COLDFIRE) { 431 __asm__ volatile ("frestore %0" : : "m" (*fpstate)); 432 } else { 433 __asm__ volatile (".chip 68k/68881\n\t" 434 "frestore %0\n\t" 435 ".chip 68k" 436 : : "m" (*fpstate)); 437 } 438 err = 0; 439 440 out: 441 return err; 442 } 443 444 /* 445 * Set up a signal frame. 446 */ 447 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 448 { 449 if (FPU_IS_EMU) { 450 /* save registers */ 451 memcpy(sc->sc_fpcntl, current->thread.fpcntl, 12); 452 memcpy(sc->sc_fpregs, current->thread.fp, 24); 453 return; 454 } 455 456 if (CPU_IS_COLDFIRE) { 457 __asm__ volatile ("fsave %0" 458 : : "m" (*sc->sc_fpstate) : "memory"); 459 } else { 460 __asm__ volatile (".chip 68k/68881\n\t" 461 "fsave %0\n\t" 462 ".chip 68k" 463 : : "m" (*sc->sc_fpstate) : "memory"); 464 } 465 466 if (CPU_IS_060 ? sc->sc_fpstate[2] : sc->sc_fpstate[0]) { 467 fpu_version = sc->sc_fpstate[0]; 468 if (CPU_IS_020_OR_030 && 469 regs->vector >= (VEC_FPBRUC * 4) && 470 regs->vector <= (VEC_FPNAN * 4)) { 471 /* Clear pending exception in 68882 idle frame */ 472 if (*(unsigned short *) sc->sc_fpstate == 0x1f38) 473 sc->sc_fpstate[0x38] |= 1 << 3; 474 } 475 476 if (CPU_IS_COLDFIRE) { 477 __asm__ volatile ("fmovemd %%fp0-%%fp1,%0\n\t" 478 "fmovel %%fpcr,%1\n\t" 479 "fmovel %%fpsr,%2\n\t" 480 "fmovel %%fpiar,%3" 481 : "=m" (sc->sc_fpregs[0]), 482 "=m" (sc->sc_fpcntl[0]), 483 "=m" (sc->sc_fpcntl[1]), 484 "=m" (sc->sc_fpcntl[2]) 485 : /* no inputs */ 486 : "memory"); 487 } else { 488 __asm__ volatile (".chip 68k/68881\n\t" 489 "fmovemx %%fp0-%%fp1,%0\n\t" 490 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 491 ".chip 68k" 492 : "=m" (*sc->sc_fpregs), 493 "=m" (*sc->sc_fpcntl) 494 : /* no inputs */ 495 : "memory"); 496 } 497 } 498 } 499 500 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 501 { 502 unsigned char fpstate[FPCONTEXT_SIZE]; 503 int context_size = CPU_IS_060 ? 8 : (CPU_IS_COLDFIRE ? 12 : 0); 504 int err = 0; 505 506 if (FPU_IS_EMU) { 507 /* save fpu control register */ 508 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpcntl, 509 current->thread.fpcntl, 12); 510 /* save all other fpu register */ 511 err |= copy_to_user(uc->uc_mcontext.fpregs.f_fpregs, 512 current->thread.fp, 96); 513 return err; 514 } 515 516 if (CPU_IS_COLDFIRE) { 517 __asm__ volatile ("fsave %0" : : "m" (*fpstate) : "memory"); 518 } else { 519 __asm__ volatile (".chip 68k/68881\n\t" 520 "fsave %0\n\t" 521 ".chip 68k" 522 : : "m" (*fpstate) : "memory"); 523 } 524 525 err |= __put_user(*(long *)fpstate, (long __user *)&uc->uc_fpstate); 526 if (CPU_IS_060 ? fpstate[2] : fpstate[0]) { 527 fpregset_t fpregs; 528 if (!(CPU_IS_060 || CPU_IS_COLDFIRE)) 529 context_size = fpstate[1]; 530 fpu_version = fpstate[0]; 531 if (CPU_IS_020_OR_030 && 532 regs->vector >= (VEC_FPBRUC * 4) && 533 regs->vector <= (VEC_FPNAN * 4)) { 534 /* Clear pending exception in 68882 idle frame */ 535 if (*(unsigned short *) fpstate == 0x1f38) 536 fpstate[0x38] |= 1 << 3; 537 } 538 if (CPU_IS_COLDFIRE) { 539 __asm__ volatile ("fmovemd %%fp0-%%fp7,%0\n\t" 540 "fmovel %%fpcr,%1\n\t" 541 "fmovel %%fpsr,%2\n\t" 542 "fmovel %%fpiar,%3" 543 : "=m" (fpregs.f_fpregs[0]), 544 "=m" (fpregs.f_fpcntl[0]), 545 "=m" (fpregs.f_fpcntl[1]), 546 "=m" (fpregs.f_fpcntl[2]) 547 : /* no inputs */ 548 : "memory"); 549 } else { 550 __asm__ volatile (".chip 68k/68881\n\t" 551 "fmovemx %%fp0-%%fp7,%0\n\t" 552 "fmoveml %%fpcr/%%fpsr/%%fpiar,%1\n\t" 553 ".chip 68k" 554 : "=m" (*fpregs.f_fpregs), 555 "=m" (*fpregs.f_fpcntl) 556 : /* no inputs */ 557 : "memory"); 558 } 559 err |= copy_to_user(&uc->uc_mcontext.fpregs, &fpregs, 560 sizeof(fpregs)); 561 } 562 if (context_size) 563 err |= copy_to_user((long __user *)&uc->uc_fpstate + 1, fpstate + 4, 564 context_size); 565 return err; 566 } 567 568 #else /* CONFIG_FPU */ 569 570 /* 571 * For the case with no FPU configured these all do nothing. 572 */ 573 static inline int restore_fpu_state(struct sigcontext *sc) 574 { 575 return 0; 576 } 577 578 static inline int rt_restore_fpu_state(struct ucontext __user *uc) 579 { 580 return 0; 581 } 582 583 static inline void save_fpu_state(struct sigcontext *sc, struct pt_regs *regs) 584 { 585 } 586 587 static inline int rt_save_fpu_state(struct ucontext __user *uc, struct pt_regs *regs) 588 { 589 return 0; 590 } 591 592 #endif /* CONFIG_FPU */ 593 594 static int mangle_kernel_stack(struct pt_regs *regs, int formatvec, 595 void __user *fp) 596 { 597 int fsize = frame_extra_sizes(formatvec >> 12); 598 if (fsize < 0) { 599 /* 600 * user process trying to return with weird frame format 601 */ 602 #ifdef DEBUG 603 printk("user process returning with weird frame format\n"); 604 #endif 605 return 1; 606 } 607 if (!fsize) { 608 regs->format = formatvec >> 12; 609 regs->vector = formatvec & 0xfff; 610 } else { 611 struct switch_stack *sw = (struct switch_stack *)regs - 1; 612 unsigned long buf[fsize / 2]; /* yes, twice as much */ 613 614 /* that'll make sure that expansion won't crap over data */ 615 if (copy_from_user(buf + fsize / 4, fp, fsize)) 616 return 1; 617 618 /* point of no return */ 619 regs->format = formatvec >> 12; 620 regs->vector = formatvec & 0xfff; 621 #define frame_offset (sizeof(struct pt_regs)+sizeof(struct switch_stack)) 622 __asm__ __volatile__ ( 623 #ifdef CONFIG_COLDFIRE 624 " movel %0,%/sp\n\t" 625 " bra ret_from_signal\n" 626 #else 627 " movel %0,%/a0\n\t" 628 " subl %1,%/a0\n\t" /* make room on stack */ 629 " movel %/a0,%/sp\n\t" /* set stack pointer */ 630 /* move switch_stack and pt_regs */ 631 "1: movel %0@+,%/a0@+\n\t" 632 " dbra %2,1b\n\t" 633 " lea %/sp@(%c3),%/a0\n\t" /* add offset of fmt */ 634 " lsrl #2,%1\n\t" 635 " subql #1,%1\n\t" 636 /* copy to the gap we'd made */ 637 "2: movel %4@+,%/a0@+\n\t" 638 " dbra %1,2b\n\t" 639 " bral ret_from_signal\n" 640 #endif 641 : /* no outputs, it doesn't ever return */ 642 : "a" (sw), "d" (fsize), "d" (frame_offset/4-1), 643 "n" (frame_offset), "a" (buf + fsize/4) 644 : "a0"); 645 #undef frame_offset 646 } 647 return 0; 648 } 649 650 static inline int 651 restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *usc, void __user *fp) 652 { 653 int formatvec; 654 struct sigcontext context; 655 int err = 0; 656 657 /* Always make any pending restarted system calls return -EINTR */ 658 current->restart_block.fn = do_no_restart_syscall; 659 660 /* get previous context */ 661 if (copy_from_user(&context, usc, sizeof(context))) 662 goto badframe; 663 664 /* restore passed registers */ 665 regs->d0 = context.sc_d0; 666 regs->d1 = context.sc_d1; 667 regs->a0 = context.sc_a0; 668 regs->a1 = context.sc_a1; 669 regs->sr = (regs->sr & 0xff00) | (context.sc_sr & 0xff); 670 regs->pc = context.sc_pc; 671 regs->orig_d0 = -1; /* disable syscall checks */ 672 wrusp(context.sc_usp); 673 formatvec = context.sc_formatvec; 674 675 err = restore_fpu_state(&context); 676 677 if (err || mangle_kernel_stack(regs, formatvec, fp)) 678 goto badframe; 679 680 return 0; 681 682 badframe: 683 return 1; 684 } 685 686 static inline int 687 rt_restore_ucontext(struct pt_regs *regs, struct switch_stack *sw, 688 struct ucontext __user *uc) 689 { 690 int temp; 691 greg_t __user *gregs = uc->uc_mcontext.gregs; 692 unsigned long usp; 693 int err; 694 695 /* Always make any pending restarted system calls return -EINTR */ 696 current->restart_block.fn = do_no_restart_syscall; 697 698 err = __get_user(temp, &uc->uc_mcontext.version); 699 if (temp != MCONTEXT_VERSION) 700 goto badframe; 701 /* restore passed registers */ 702 err |= __get_user(regs->d0, &gregs[0]); 703 err |= __get_user(regs->d1, &gregs[1]); 704 err |= __get_user(regs->d2, &gregs[2]); 705 err |= __get_user(regs->d3, &gregs[3]); 706 err |= __get_user(regs->d4, &gregs[4]); 707 err |= __get_user(regs->d5, &gregs[5]); 708 err |= __get_user(sw->d6, &gregs[6]); 709 err |= __get_user(sw->d7, &gregs[7]); 710 err |= __get_user(regs->a0, &gregs[8]); 711 err |= __get_user(regs->a1, &gregs[9]); 712 err |= __get_user(regs->a2, &gregs[10]); 713 err |= __get_user(sw->a3, &gregs[11]); 714 err |= __get_user(sw->a4, &gregs[12]); 715 err |= __get_user(sw->a5, &gregs[13]); 716 err |= __get_user(sw->a6, &gregs[14]); 717 err |= __get_user(usp, &gregs[15]); 718 wrusp(usp); 719 err |= __get_user(regs->pc, &gregs[16]); 720 err |= __get_user(temp, &gregs[17]); 721 regs->sr = (regs->sr & 0xff00) | (temp & 0xff); 722 regs->orig_d0 = -1; /* disable syscall checks */ 723 err |= __get_user(temp, &uc->uc_formatvec); 724 725 err |= rt_restore_fpu_state(uc); 726 err |= restore_altstack(&uc->uc_stack); 727 728 if (err) 729 goto badframe; 730 731 if (mangle_kernel_stack(regs, temp, &uc->uc_extra)) 732 goto badframe; 733 734 return 0; 735 736 badframe: 737 return 1; 738 } 739 740 asmlinkage int do_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 741 { 742 unsigned long usp = rdusp(); 743 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 744 sigset_t set; 745 746 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 747 goto badframe; 748 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 749 (_NSIG_WORDS > 1 && 750 __copy_from_user(&set.sig[1], &frame->extramask, 751 sizeof(frame->extramask)))) 752 goto badframe; 753 754 set_current_blocked(&set); 755 756 if (restore_sigcontext(regs, &frame->sc, frame + 1)) 757 goto badframe; 758 return regs->d0; 759 760 badframe: 761 force_sig(SIGSEGV, current); 762 return 0; 763 } 764 765 asmlinkage int do_rt_sigreturn(struct pt_regs *regs, struct switch_stack *sw) 766 { 767 unsigned long usp = rdusp(); 768 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 769 sigset_t set; 770 771 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 772 goto badframe; 773 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 774 goto badframe; 775 776 set_current_blocked(&set); 777 778 if (rt_restore_ucontext(regs, sw, &frame->uc)) 779 goto badframe; 780 return regs->d0; 781 782 badframe: 783 force_sig(SIGSEGV, current); 784 return 0; 785 } 786 787 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 788 unsigned long mask) 789 { 790 sc->sc_mask = mask; 791 sc->sc_usp = rdusp(); 792 sc->sc_d0 = regs->d0; 793 sc->sc_d1 = regs->d1; 794 sc->sc_a0 = regs->a0; 795 sc->sc_a1 = regs->a1; 796 sc->sc_sr = regs->sr; 797 sc->sc_pc = regs->pc; 798 sc->sc_formatvec = regs->format << 12 | regs->vector; 799 save_a5_state(sc, regs); 800 save_fpu_state(sc, regs); 801 } 802 803 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 804 { 805 struct switch_stack *sw = (struct switch_stack *)regs - 1; 806 greg_t __user *gregs = uc->uc_mcontext.gregs; 807 int err = 0; 808 809 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 810 err |= __put_user(regs->d0, &gregs[0]); 811 err |= __put_user(regs->d1, &gregs[1]); 812 err |= __put_user(regs->d2, &gregs[2]); 813 err |= __put_user(regs->d3, &gregs[3]); 814 err |= __put_user(regs->d4, &gregs[4]); 815 err |= __put_user(regs->d5, &gregs[5]); 816 err |= __put_user(sw->d6, &gregs[6]); 817 err |= __put_user(sw->d7, &gregs[7]); 818 err |= __put_user(regs->a0, &gregs[8]); 819 err |= __put_user(regs->a1, &gregs[9]); 820 err |= __put_user(regs->a2, &gregs[10]); 821 err |= __put_user(sw->a3, &gregs[11]); 822 err |= __put_user(sw->a4, &gregs[12]); 823 err |= __put_user(sw->a5, &gregs[13]); 824 err |= __put_user(sw->a6, &gregs[14]); 825 err |= __put_user(rdusp(), &gregs[15]); 826 err |= __put_user(regs->pc, &gregs[16]); 827 err |= __put_user(regs->sr, &gregs[17]); 828 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); 829 err |= rt_save_fpu_state(uc, regs); 830 return err; 831 } 832 833 static inline void __user * 834 get_sigframe(struct ksignal *ksig, size_t frame_size) 835 { 836 unsigned long usp = sigsp(rdusp(), ksig); 837 838 return (void __user *)((usp - frame_size) & -8UL); 839 } 840 841 static int setup_frame(struct ksignal *ksig, sigset_t *set, 842 struct pt_regs *regs) 843 { 844 struct sigframe __user *frame; 845 int fsize = frame_extra_sizes(regs->format); 846 struct sigcontext context; 847 int err = 0, sig = ksig->sig; 848 849 if (fsize < 0) { 850 #ifdef DEBUG 851 printk ("setup_frame: Unknown frame format %#x\n", 852 regs->format); 853 #endif 854 return -EFAULT; 855 } 856 857 frame = get_sigframe(ksig, sizeof(*frame) + fsize); 858 859 if (fsize) 860 err |= copy_to_user (frame + 1, regs + 1, fsize); 861 862 err |= __put_user(sig, &frame->sig); 863 864 err |= __put_user(regs->vector, &frame->code); 865 err |= __put_user(&frame->sc, &frame->psc); 866 867 if (_NSIG_WORDS > 1) 868 err |= copy_to_user(frame->extramask, &set->sig[1], 869 sizeof(frame->extramask)); 870 871 setup_sigcontext(&context, regs, set->sig[0]); 872 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 873 874 /* Set up to return from userspace. */ 875 #ifdef CONFIG_MMU 876 err |= __put_user(frame->retcode, &frame->pretcode); 877 /* moveq #,d0; trap #0 */ 878 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 879 (long __user *)(frame->retcode)); 880 #else 881 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode); 882 #endif 883 884 if (err) 885 return -EFAULT; 886 887 push_cache ((unsigned long) &frame->retcode); 888 889 /* 890 * Set up registers for signal handler. All the state we are about 891 * to destroy is successfully copied to sigframe. 892 */ 893 wrusp ((unsigned long) frame); 894 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 895 adjustformat(regs); 896 897 /* 898 * This is subtle; if we build more than one sigframe, all but the 899 * first one will see frame format 0 and have fsize == 0, so we won't 900 * screw stkadj. 901 */ 902 if (fsize) 903 regs->stkadj = fsize; 904 905 /* Prepare to skip over the extra stuff in the exception frame. */ 906 if (regs->stkadj) { 907 struct pt_regs *tregs = 908 (struct pt_regs *)((ulong)regs + regs->stkadj); 909 #ifdef DEBUG 910 printk("Performing stackadjust=%04x\n", regs->stkadj); 911 #endif 912 /* This must be copied with decreasing addresses to 913 handle overlaps. */ 914 tregs->vector = 0; 915 tregs->format = 0; 916 tregs->pc = regs->pc; 917 tregs->sr = regs->sr; 918 } 919 return 0; 920 } 921 922 static int setup_rt_frame(struct ksignal *ksig, sigset_t *set, 923 struct pt_regs *regs) 924 { 925 struct rt_sigframe __user *frame; 926 int fsize = frame_extra_sizes(regs->format); 927 int err = 0, sig = ksig->sig; 928 929 if (fsize < 0) { 930 #ifdef DEBUG 931 printk ("setup_frame: Unknown frame format %#x\n", 932 regs->format); 933 #endif 934 return -EFAULT; 935 } 936 937 frame = get_sigframe(ksig, sizeof(*frame)); 938 939 if (fsize) 940 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 941 942 err |= __put_user(sig, &frame->sig); 943 err |= __put_user(&frame->info, &frame->pinfo); 944 err |= __put_user(&frame->uc, &frame->puc); 945 err |= copy_siginfo_to_user(&frame->info, &ksig->info); 946 947 /* Create the ucontext. */ 948 err |= __put_user(0, &frame->uc.uc_flags); 949 err |= __put_user(NULL, &frame->uc.uc_link); 950 err |= __save_altstack(&frame->uc.uc_stack, rdusp()); 951 err |= rt_setup_ucontext(&frame->uc, regs); 952 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 953 954 /* Set up to return from userspace. */ 955 #ifdef CONFIG_MMU 956 err |= __put_user(frame->retcode, &frame->pretcode); 957 #ifdef __mcoldfire__ 958 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 959 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 960 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 961 (long __user *)(frame->retcode + 4)); 962 #else 963 /* moveq #,d0; notb d0; trap #0 */ 964 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 965 (long __user *)(frame->retcode + 0)); 966 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 967 #endif 968 #else 969 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode); 970 #endif /* CONFIG_MMU */ 971 972 if (err) 973 return -EFAULT; 974 975 push_cache ((unsigned long) &frame->retcode); 976 977 /* 978 * Set up registers for signal handler. All the state we are about 979 * to destroy is successfully copied to sigframe. 980 */ 981 wrusp ((unsigned long) frame); 982 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 983 adjustformat(regs); 984 985 /* 986 * This is subtle; if we build more than one sigframe, all but the 987 * first one will see frame format 0 and have fsize == 0, so we won't 988 * screw stkadj. 989 */ 990 if (fsize) 991 regs->stkadj = fsize; 992 993 /* Prepare to skip over the extra stuff in the exception frame. */ 994 if (regs->stkadj) { 995 struct pt_regs *tregs = 996 (struct pt_regs *)((ulong)regs + regs->stkadj); 997 #ifdef DEBUG 998 printk("Performing stackadjust=%04x\n", regs->stkadj); 999 #endif 1000 /* This must be copied with decreasing addresses to 1001 handle overlaps. */ 1002 tregs->vector = 0; 1003 tregs->format = 0; 1004 tregs->pc = regs->pc; 1005 tregs->sr = regs->sr; 1006 } 1007 return 0; 1008 } 1009 1010 static inline void 1011 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1012 { 1013 switch (regs->d0) { 1014 case -ERESTARTNOHAND: 1015 if (!has_handler) 1016 goto do_restart; 1017 regs->d0 = -EINTR; 1018 break; 1019 1020 case -ERESTART_RESTARTBLOCK: 1021 if (!has_handler) { 1022 regs->d0 = __NR_restart_syscall; 1023 regs->pc -= 2; 1024 break; 1025 } 1026 regs->d0 = -EINTR; 1027 break; 1028 1029 case -ERESTARTSYS: 1030 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1031 regs->d0 = -EINTR; 1032 break; 1033 } 1034 /* fallthrough */ 1035 case -ERESTARTNOINTR: 1036 do_restart: 1037 regs->d0 = regs->orig_d0; 1038 regs->pc -= 2; 1039 break; 1040 } 1041 } 1042 1043 /* 1044 * OK, we're invoking a handler 1045 */ 1046 static void 1047 handle_signal(struct ksignal *ksig, struct pt_regs *regs) 1048 { 1049 sigset_t *oldset = sigmask_to_save(); 1050 int err; 1051 /* are we from a system call? */ 1052 if (regs->orig_d0 >= 0) 1053 /* If so, check system call restarting.. */ 1054 handle_restart(regs, &ksig->ka, 1); 1055 1056 /* set up the stack frame */ 1057 if (ksig->ka.sa.sa_flags & SA_SIGINFO) 1058 err = setup_rt_frame(ksig, oldset, regs); 1059 else 1060 err = setup_frame(ksig, oldset, regs); 1061 1062 signal_setup_done(err, ksig, 0); 1063 1064 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1065 regs->sr &= ~0x8000; 1066 send_sig(SIGTRAP, current, 1); 1067 } 1068 } 1069 1070 /* 1071 * Note that 'init' is a special process: it doesn't get signals it doesn't 1072 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1073 * mistake. 1074 */ 1075 static void do_signal(struct pt_regs *regs) 1076 { 1077 struct ksignal ksig; 1078 1079 current->thread.esp0 = (unsigned long) regs; 1080 1081 if (get_signal(&ksig)) { 1082 /* Whee! Actually deliver the signal. */ 1083 handle_signal(&ksig, regs); 1084 return; 1085 } 1086 1087 /* Did we come from a system call? */ 1088 if (regs->orig_d0 >= 0) 1089 /* Restart the system call - no handlers present */ 1090 handle_restart(regs, NULL, 0); 1091 1092 /* If there's no signal to deliver, we just restore the saved mask. */ 1093 restore_saved_sigmask(); 1094 } 1095 1096 void do_notify_resume(struct pt_regs *regs) 1097 { 1098 if (test_thread_flag(TIF_SIGPENDING)) 1099 do_signal(regs); 1100 1101 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) 1102 tracehook_notify_resume(regs); 1103 } 1104