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_thread_info()->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_thread_info()->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(unsigned long __unused) 741 { 742 struct switch_stack *sw = (struct switch_stack *) &__unused; 743 struct pt_regs *regs = (struct pt_regs *) (sw + 1); 744 unsigned long usp = rdusp(); 745 struct sigframe __user *frame = (struct sigframe __user *)(usp - 4); 746 sigset_t set; 747 748 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 749 goto badframe; 750 if (__get_user(set.sig[0], &frame->sc.sc_mask) || 751 (_NSIG_WORDS > 1 && 752 __copy_from_user(&set.sig[1], &frame->extramask, 753 sizeof(frame->extramask)))) 754 goto badframe; 755 756 set_current_blocked(&set); 757 758 if (restore_sigcontext(regs, &frame->sc, frame + 1)) 759 goto badframe; 760 return regs->d0; 761 762 badframe: 763 force_sig(SIGSEGV, current); 764 return 0; 765 } 766 767 asmlinkage int do_rt_sigreturn(unsigned long __unused) 768 { 769 struct switch_stack *sw = (struct switch_stack *) &__unused; 770 struct pt_regs *regs = (struct pt_regs *) (sw + 1); 771 unsigned long usp = rdusp(); 772 struct rt_sigframe __user *frame = (struct rt_sigframe __user *)(usp - 4); 773 sigset_t set; 774 775 if (!access_ok(VERIFY_READ, frame, sizeof(*frame))) 776 goto badframe; 777 if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) 778 goto badframe; 779 780 set_current_blocked(&set); 781 782 if (rt_restore_ucontext(regs, sw, &frame->uc)) 783 goto badframe; 784 return regs->d0; 785 786 badframe: 787 force_sig(SIGSEGV, current); 788 return 0; 789 } 790 791 static void setup_sigcontext(struct sigcontext *sc, struct pt_regs *regs, 792 unsigned long mask) 793 { 794 sc->sc_mask = mask; 795 sc->sc_usp = rdusp(); 796 sc->sc_d0 = regs->d0; 797 sc->sc_d1 = regs->d1; 798 sc->sc_a0 = regs->a0; 799 sc->sc_a1 = regs->a1; 800 sc->sc_sr = regs->sr; 801 sc->sc_pc = regs->pc; 802 sc->sc_formatvec = regs->format << 12 | regs->vector; 803 save_a5_state(sc, regs); 804 save_fpu_state(sc, regs); 805 } 806 807 static inline int rt_setup_ucontext(struct ucontext __user *uc, struct pt_regs *regs) 808 { 809 struct switch_stack *sw = (struct switch_stack *)regs - 1; 810 greg_t __user *gregs = uc->uc_mcontext.gregs; 811 int err = 0; 812 813 err |= __put_user(MCONTEXT_VERSION, &uc->uc_mcontext.version); 814 err |= __put_user(regs->d0, &gregs[0]); 815 err |= __put_user(regs->d1, &gregs[1]); 816 err |= __put_user(regs->d2, &gregs[2]); 817 err |= __put_user(regs->d3, &gregs[3]); 818 err |= __put_user(regs->d4, &gregs[4]); 819 err |= __put_user(regs->d5, &gregs[5]); 820 err |= __put_user(sw->d6, &gregs[6]); 821 err |= __put_user(sw->d7, &gregs[7]); 822 err |= __put_user(regs->a0, &gregs[8]); 823 err |= __put_user(regs->a1, &gregs[9]); 824 err |= __put_user(regs->a2, &gregs[10]); 825 err |= __put_user(sw->a3, &gregs[11]); 826 err |= __put_user(sw->a4, &gregs[12]); 827 err |= __put_user(sw->a5, &gregs[13]); 828 err |= __put_user(sw->a6, &gregs[14]); 829 err |= __put_user(rdusp(), &gregs[15]); 830 err |= __put_user(regs->pc, &gregs[16]); 831 err |= __put_user(regs->sr, &gregs[17]); 832 err |= __put_user((regs->format << 12) | regs->vector, &uc->uc_formatvec); 833 err |= rt_save_fpu_state(uc, regs); 834 return err; 835 } 836 837 static inline void __user * 838 get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size) 839 { 840 unsigned long usp; 841 842 /* Default to using normal stack. */ 843 usp = rdusp(); 844 845 /* This is the X/Open sanctioned signal stack switching. */ 846 if (ka->sa.sa_flags & SA_ONSTACK) { 847 if (!sas_ss_flags(usp)) 848 usp = current->sas_ss_sp + current->sas_ss_size; 849 } 850 return (void __user *)((usp - frame_size) & -8UL); 851 } 852 853 static int setup_frame (int sig, struct k_sigaction *ka, 854 sigset_t *set, struct pt_regs *regs) 855 { 856 struct sigframe __user *frame; 857 int fsize = frame_extra_sizes(regs->format); 858 struct sigcontext context; 859 int err = 0; 860 861 if (fsize < 0) { 862 #ifdef DEBUG 863 printk ("setup_frame: Unknown frame format %#x\n", 864 regs->format); 865 #endif 866 goto give_sigsegv; 867 } 868 869 frame = get_sigframe(ka, regs, sizeof(*frame) + fsize); 870 871 if (fsize) 872 err |= copy_to_user (frame + 1, regs + 1, fsize); 873 874 err |= __put_user((current_thread_info()->exec_domain 875 && current_thread_info()->exec_domain->signal_invmap 876 && sig < 32 877 ? current_thread_info()->exec_domain->signal_invmap[sig] 878 : sig), 879 &frame->sig); 880 881 err |= __put_user(regs->vector, &frame->code); 882 err |= __put_user(&frame->sc, &frame->psc); 883 884 if (_NSIG_WORDS > 1) 885 err |= copy_to_user(frame->extramask, &set->sig[1], 886 sizeof(frame->extramask)); 887 888 setup_sigcontext(&context, regs, set->sig[0]); 889 err |= copy_to_user (&frame->sc, &context, sizeof(context)); 890 891 /* Set up to return from userspace. */ 892 #ifdef CONFIG_MMU 893 err |= __put_user(frame->retcode, &frame->pretcode); 894 /* moveq #,d0; trap #0 */ 895 err |= __put_user(0x70004e40 + (__NR_sigreturn << 16), 896 (long __user *)(frame->retcode)); 897 #else 898 err |= __put_user((void *) ret_from_user_signal, &frame->pretcode); 899 #endif 900 901 if (err) 902 goto give_sigsegv; 903 904 push_cache ((unsigned long) &frame->retcode); 905 906 /* 907 * Set up registers for signal handler. All the state we are about 908 * to destroy is successfully copied to sigframe. 909 */ 910 wrusp ((unsigned long) frame); 911 regs->pc = (unsigned long) ka->sa.sa_handler; 912 adjustformat(regs); 913 914 /* 915 * This is subtle; if we build more than one sigframe, all but the 916 * first one will see frame format 0 and have fsize == 0, so we won't 917 * screw stkadj. 918 */ 919 if (fsize) 920 regs->stkadj = fsize; 921 922 /* Prepare to skip over the extra stuff in the exception frame. */ 923 if (regs->stkadj) { 924 struct pt_regs *tregs = 925 (struct pt_regs *)((ulong)regs + regs->stkadj); 926 #ifdef DEBUG 927 printk("Performing stackadjust=%04x\n", regs->stkadj); 928 #endif 929 /* This must be copied with decreasing addresses to 930 handle overlaps. */ 931 tregs->vector = 0; 932 tregs->format = 0; 933 tregs->pc = regs->pc; 934 tregs->sr = regs->sr; 935 } 936 return 0; 937 938 give_sigsegv: 939 force_sigsegv(sig, current); 940 return err; 941 } 942 943 static int setup_rt_frame (int sig, struct k_sigaction *ka, siginfo_t *info, 944 sigset_t *set, struct pt_regs *regs) 945 { 946 struct rt_sigframe __user *frame; 947 int fsize = frame_extra_sizes(regs->format); 948 int err = 0; 949 950 if (fsize < 0) { 951 #ifdef DEBUG 952 printk ("setup_frame: Unknown frame format %#x\n", 953 regs->format); 954 #endif 955 goto give_sigsegv; 956 } 957 958 frame = get_sigframe(ka, regs, sizeof(*frame)); 959 960 if (fsize) 961 err |= copy_to_user (&frame->uc.uc_extra, regs + 1, fsize); 962 963 err |= __put_user((current_thread_info()->exec_domain 964 && current_thread_info()->exec_domain->signal_invmap 965 && sig < 32 966 ? current_thread_info()->exec_domain->signal_invmap[sig] 967 : sig), 968 &frame->sig); 969 err |= __put_user(&frame->info, &frame->pinfo); 970 err |= __put_user(&frame->uc, &frame->puc); 971 err |= copy_siginfo_to_user(&frame->info, info); 972 973 /* Create the ucontext. */ 974 err |= __put_user(0, &frame->uc.uc_flags); 975 err |= __put_user(NULL, &frame->uc.uc_link); 976 err |= __save_altstack(&frame->uc.uc_stack, rdusp()); 977 err |= rt_setup_ucontext(&frame->uc, regs); 978 err |= copy_to_user (&frame->uc.uc_sigmask, set, sizeof(*set)); 979 980 /* Set up to return from userspace. */ 981 #ifdef CONFIG_MMU 982 err |= __put_user(frame->retcode, &frame->pretcode); 983 #ifdef __mcoldfire__ 984 /* movel #__NR_rt_sigreturn,d0; trap #0 */ 985 err |= __put_user(0x203c0000, (long __user *)(frame->retcode + 0)); 986 err |= __put_user(0x00004e40 + (__NR_rt_sigreturn << 16), 987 (long __user *)(frame->retcode + 4)); 988 #else 989 /* moveq #,d0; notb d0; trap #0 */ 990 err |= __put_user(0x70004600 + ((__NR_rt_sigreturn ^ 0xff) << 16), 991 (long __user *)(frame->retcode + 0)); 992 err |= __put_user(0x4e40, (short __user *)(frame->retcode + 4)); 993 #endif 994 #else 995 err |= __put_user((void *) ret_from_user_rt_signal, &frame->pretcode); 996 #endif /* CONFIG_MMU */ 997 998 if (err) 999 goto give_sigsegv; 1000 1001 push_cache ((unsigned long) &frame->retcode); 1002 1003 /* 1004 * Set up registers for signal handler. All the state we are about 1005 * to destroy is successfully copied to sigframe. 1006 */ 1007 wrusp ((unsigned long) frame); 1008 regs->pc = (unsigned long) ka->sa.sa_handler; 1009 adjustformat(regs); 1010 1011 /* 1012 * This is subtle; if we build more than one sigframe, all but the 1013 * first one will see frame format 0 and have fsize == 0, so we won't 1014 * screw stkadj. 1015 */ 1016 if (fsize) 1017 regs->stkadj = fsize; 1018 1019 /* Prepare to skip over the extra stuff in the exception frame. */ 1020 if (regs->stkadj) { 1021 struct pt_regs *tregs = 1022 (struct pt_regs *)((ulong)regs + regs->stkadj); 1023 #ifdef DEBUG 1024 printk("Performing stackadjust=%04x\n", regs->stkadj); 1025 #endif 1026 /* This must be copied with decreasing addresses to 1027 handle overlaps. */ 1028 tregs->vector = 0; 1029 tregs->format = 0; 1030 tregs->pc = regs->pc; 1031 tregs->sr = regs->sr; 1032 } 1033 return 0; 1034 1035 give_sigsegv: 1036 force_sigsegv(sig, current); 1037 return err; 1038 } 1039 1040 static inline void 1041 handle_restart(struct pt_regs *regs, struct k_sigaction *ka, int has_handler) 1042 { 1043 switch (regs->d0) { 1044 case -ERESTARTNOHAND: 1045 if (!has_handler) 1046 goto do_restart; 1047 regs->d0 = -EINTR; 1048 break; 1049 1050 case -ERESTART_RESTARTBLOCK: 1051 if (!has_handler) { 1052 regs->d0 = __NR_restart_syscall; 1053 regs->pc -= 2; 1054 break; 1055 } 1056 regs->d0 = -EINTR; 1057 break; 1058 1059 case -ERESTARTSYS: 1060 if (has_handler && !(ka->sa.sa_flags & SA_RESTART)) { 1061 regs->d0 = -EINTR; 1062 break; 1063 } 1064 /* fallthrough */ 1065 case -ERESTARTNOINTR: 1066 do_restart: 1067 regs->d0 = regs->orig_d0; 1068 regs->pc -= 2; 1069 break; 1070 } 1071 } 1072 1073 /* 1074 * OK, we're invoking a handler 1075 */ 1076 static void 1077 handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info, 1078 struct pt_regs *regs) 1079 { 1080 sigset_t *oldset = sigmask_to_save(); 1081 int err; 1082 /* are we from a system call? */ 1083 if (regs->orig_d0 >= 0) 1084 /* If so, check system call restarting.. */ 1085 handle_restart(regs, ka, 1); 1086 1087 /* set up the stack frame */ 1088 if (ka->sa.sa_flags & SA_SIGINFO) 1089 err = setup_rt_frame(sig, ka, info, oldset, regs); 1090 else 1091 err = setup_frame(sig, ka, oldset, regs); 1092 1093 if (err) 1094 return; 1095 1096 signal_delivered(sig, info, ka, regs, 0); 1097 1098 if (test_thread_flag(TIF_DELAYED_TRACE)) { 1099 regs->sr &= ~0x8000; 1100 send_sig(SIGTRAP, current, 1); 1101 } 1102 } 1103 1104 /* 1105 * Note that 'init' is a special process: it doesn't get signals it doesn't 1106 * want to handle. Thus you cannot kill init even with a SIGKILL even by 1107 * mistake. 1108 */ 1109 static void do_signal(struct pt_regs *regs) 1110 { 1111 siginfo_t info; 1112 struct k_sigaction ka; 1113 int signr; 1114 1115 current->thread.esp0 = (unsigned long) regs; 1116 1117 signr = get_signal_to_deliver(&info, &ka, regs, NULL); 1118 if (signr > 0) { 1119 /* Whee! Actually deliver the signal. */ 1120 handle_signal(signr, &ka, &info, regs); 1121 return; 1122 } 1123 1124 /* Did we come from a system call? */ 1125 if (regs->orig_d0 >= 0) 1126 /* Restart the system call - no handlers present */ 1127 handle_restart(regs, NULL, 0); 1128 1129 /* If there's no signal to deliver, we just restore the saved mask. */ 1130 restore_saved_sigmask(); 1131 } 1132 1133 void do_notify_resume(struct pt_regs *regs) 1134 { 1135 if (test_thread_flag(TIF_SIGPENDING)) 1136 do_signal(regs); 1137 1138 if (test_and_clear_thread_flag(TIF_NOTIFY_RESUME)) 1139 tracehook_notify_resume(regs); 1140 } 1141