Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/arch/alpha/kernel/signal.c |
| 3 | * |
| 4 | * Copyright (C) 1995 Linus Torvalds |
| 5 | * |
| 6 | * 1997-11-02 Modified for POSIX.1b signals by Richard Henderson |
| 7 | */ |
| 8 | |
| 9 | #include <linux/sched.h> |
| 10 | #include <linux/kernel.h> |
| 11 | #include <linux/signal.h> |
| 12 | #include <linux/errno.h> |
| 13 | #include <linux/wait.h> |
| 14 | #include <linux/ptrace.h> |
| 15 | #include <linux/unistd.h> |
| 16 | #include <linux/mm.h> |
| 17 | #include <linux/smp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | #include <linux/stddef.h> |
| 19 | #include <linux/tty.h> |
| 20 | #include <linux/binfmts.h> |
| 21 | #include <linux/bitops.h> |
| 22 | |
| 23 | #include <asm/uaccess.h> |
| 24 | #include <asm/sigcontext.h> |
| 25 | #include <asm/ucontext.h> |
| 26 | |
| 27 | #include "proto.h" |
| 28 | |
| 29 | |
| 30 | #define DEBUG_SIG 0 |
| 31 | |
| 32 | #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) |
| 33 | |
| 34 | asmlinkage void ret_from_sys_call(void); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 35 | static void do_signal(struct pt_regs *, struct switch_stack *, |
| 36 | unsigned long, unsigned long); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 37 | |
| 38 | |
| 39 | /* |
| 40 | * The OSF/1 sigprocmask calling sequence is different from the |
| 41 | * C sigprocmask() sequence.. |
| 42 | * |
| 43 | * how: |
| 44 | * 1 - SIG_BLOCK |
| 45 | * 2 - SIG_UNBLOCK |
| 46 | * 3 - SIG_SETMASK |
| 47 | * |
| 48 | * We change the range to -1 .. 1 in order to let gcc easily |
| 49 | * use the conditional move instructions. |
| 50 | * |
| 51 | * Note that we don't need to acquire the kernel lock for SMP |
| 52 | * operation, as all of this is local to this thread. |
| 53 | */ |
| 54 | asmlinkage unsigned long |
| 55 | do_osf_sigprocmask(int how, unsigned long newmask, struct pt_regs *regs) |
| 56 | { |
| 57 | unsigned long oldmask = -EINVAL; |
| 58 | |
| 59 | if ((unsigned long)how-1 <= 2) { |
| 60 | long sign = how-2; /* -1 .. 1 */ |
| 61 | unsigned long block, unblock; |
| 62 | |
| 63 | newmask &= _BLOCKABLE; |
| 64 | spin_lock_irq(¤t->sighand->siglock); |
| 65 | oldmask = current->blocked.sig[0]; |
| 66 | |
| 67 | unblock = oldmask & ~newmask; |
| 68 | block = oldmask | newmask; |
| 69 | if (!sign) |
| 70 | block = unblock; |
| 71 | if (sign <= 0) |
| 72 | newmask = block; |
| 73 | if (_NSIG_WORDS > 1 && sign > 0) |
| 74 | sigemptyset(¤t->blocked); |
| 75 | current->blocked.sig[0] = newmask; |
| 76 | recalc_sigpending(); |
| 77 | spin_unlock_irq(¤t->sighand->siglock); |
| 78 | |
| 79 | regs->r0 = 0; /* special no error return */ |
| 80 | } |
| 81 | return oldmask; |
| 82 | } |
| 83 | |
| 84 | asmlinkage int |
| 85 | osf_sigaction(int sig, const struct osf_sigaction __user *act, |
| 86 | struct osf_sigaction __user *oact) |
| 87 | { |
| 88 | struct k_sigaction new_ka, old_ka; |
| 89 | int ret; |
| 90 | |
| 91 | if (act) { |
| 92 | old_sigset_t mask; |
| 93 | if (!access_ok(VERIFY_READ, act, sizeof(*act)) || |
| 94 | __get_user(new_ka.sa.sa_handler, &act->sa_handler) || |
| 95 | __get_user(new_ka.sa.sa_flags, &act->sa_flags)) |
| 96 | return -EFAULT; |
| 97 | __get_user(mask, &act->sa_mask); |
| 98 | siginitset(&new_ka.sa.sa_mask, mask); |
| 99 | new_ka.ka_restorer = NULL; |
| 100 | } |
| 101 | |
| 102 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); |
| 103 | |
| 104 | if (!ret && oact) { |
| 105 | if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) || |
| 106 | __put_user(old_ka.sa.sa_handler, &oact->sa_handler) || |
| 107 | __put_user(old_ka.sa.sa_flags, &oact->sa_flags)) |
| 108 | return -EFAULT; |
| 109 | __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask); |
| 110 | } |
| 111 | |
| 112 | return ret; |
| 113 | } |
| 114 | |
| 115 | asmlinkage long |
| 116 | sys_rt_sigaction(int sig, const struct sigaction __user *act, |
| 117 | struct sigaction __user *oact, |
| 118 | size_t sigsetsize, void __user *restorer) |
| 119 | { |
| 120 | struct k_sigaction new_ka, old_ka; |
| 121 | int ret; |
| 122 | |
| 123 | /* XXX: Don't preclude handling different sized sigset_t's. */ |
| 124 | if (sigsetsize != sizeof(sigset_t)) |
| 125 | return -EINVAL; |
| 126 | |
| 127 | if (act) { |
| 128 | new_ka.ka_restorer = restorer; |
| 129 | if (copy_from_user(&new_ka.sa, act, sizeof(*act))) |
| 130 | return -EFAULT; |
| 131 | } |
| 132 | |
| 133 | ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); |
| 134 | |
| 135 | if (!ret && oact) { |
| 136 | if (copy_to_user(oact, &old_ka.sa, sizeof(*oact))) |
| 137 | return -EFAULT; |
| 138 | } |
| 139 | |
| 140 | return ret; |
| 141 | } |
| 142 | |
| 143 | /* |
| 144 | * Atomically swap in the new signal mask, and wait for a signal. |
| 145 | */ |
| 146 | asmlinkage int |
| 147 | do_sigsuspend(old_sigset_t mask, struct pt_regs *regs, struct switch_stack *sw) |
| 148 | { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | mask &= _BLOCKABLE; |
| 150 | spin_lock_irq(¤t->sighand->siglock); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 151 | current->saved_sigmask = current->blocked; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | siginitset(¤t->blocked, mask); |
| 153 | recalc_sigpending(); |
| 154 | spin_unlock_irq(¤t->sighand->siglock); |
| 155 | |
| 156 | /* Indicate EINTR on return from any possible signal handler, |
| 157 | which will not come back through here, but via sigreturn. */ |
| 158 | regs->r0 = EINTR; |
| 159 | regs->r19 = 1; |
| 160 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 161 | current->state = TASK_INTERRUPTIBLE; |
| 162 | schedule(); |
| 163 | set_thread_flag(TIF_RESTORE_SIGMASK); |
| 164 | return -ERESTARTNOHAND; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | } |
| 166 | |
| 167 | asmlinkage int |
| 168 | do_rt_sigsuspend(sigset_t __user *uset, size_t sigsetsize, |
| 169 | struct pt_regs *regs, struct switch_stack *sw) |
| 170 | { |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 171 | sigset_t set; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | |
| 173 | /* XXX: Don't preclude handling different sized sigset_t's. */ |
| 174 | if (sigsetsize != sizeof(sigset_t)) |
| 175 | return -EINVAL; |
| 176 | if (copy_from_user(&set, uset, sizeof(set))) |
| 177 | return -EFAULT; |
| 178 | |
| 179 | sigdelsetmask(&set, ~_BLOCKABLE); |
| 180 | spin_lock_irq(¤t->sighand->siglock); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 181 | current->saved_sigmask = current->blocked; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 182 | current->blocked = set; |
| 183 | recalc_sigpending(); |
| 184 | spin_unlock_irq(¤t->sighand->siglock); |
| 185 | |
| 186 | /* Indicate EINTR on return from any possible signal handler, |
| 187 | which will not come back through here, but via sigreturn. */ |
| 188 | regs->r0 = EINTR; |
| 189 | regs->r19 = 1; |
| 190 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 191 | current->state = TASK_INTERRUPTIBLE; |
| 192 | schedule(); |
| 193 | set_thread_flag(TIF_RESTORE_SIGMASK); |
| 194 | return -ERESTARTNOHAND; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | } |
| 196 | |
| 197 | asmlinkage int |
| 198 | sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss) |
| 199 | { |
| 200 | return do_sigaltstack(uss, uoss, rdusp()); |
| 201 | } |
| 202 | |
| 203 | /* |
| 204 | * Do a signal return; undo the signal stack. |
| 205 | */ |
| 206 | |
| 207 | #if _NSIG_WORDS > 1 |
| 208 | # error "Non SA_SIGINFO frame needs rearranging" |
| 209 | #endif |
| 210 | |
| 211 | struct sigframe |
| 212 | { |
| 213 | struct sigcontext sc; |
| 214 | unsigned int retcode[3]; |
| 215 | }; |
| 216 | |
| 217 | struct rt_sigframe |
| 218 | { |
| 219 | struct siginfo info; |
| 220 | struct ucontext uc; |
| 221 | unsigned int retcode[3]; |
| 222 | }; |
| 223 | |
| 224 | /* If this changes, userland unwinders that Know Things about our signal |
| 225 | frame will break. Do not undertake lightly. It also implies an ABI |
| 226 | change wrt the size of siginfo_t, which may cause some pain. */ |
| 227 | extern char compile_time_assert |
| 228 | [offsetof(struct rt_sigframe, uc.uc_mcontext) == 176 ? 1 : -1]; |
| 229 | |
| 230 | #define INSN_MOV_R30_R16 0x47fe0410 |
| 231 | #define INSN_LDI_R0 0x201f0000 |
| 232 | #define INSN_CALLSYS 0x00000083 |
| 233 | |
| 234 | static long |
| 235 | restore_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, |
| 236 | struct switch_stack *sw) |
| 237 | { |
| 238 | unsigned long usp; |
| 239 | long i, err = __get_user(regs->pc, &sc->sc_pc); |
| 240 | |
| 241 | sw->r26 = (unsigned long) ret_from_sys_call; |
| 242 | |
| 243 | err |= __get_user(regs->r0, sc->sc_regs+0); |
| 244 | err |= __get_user(regs->r1, sc->sc_regs+1); |
| 245 | err |= __get_user(regs->r2, sc->sc_regs+2); |
| 246 | err |= __get_user(regs->r3, sc->sc_regs+3); |
| 247 | err |= __get_user(regs->r4, sc->sc_regs+4); |
| 248 | err |= __get_user(regs->r5, sc->sc_regs+5); |
| 249 | err |= __get_user(regs->r6, sc->sc_regs+6); |
| 250 | err |= __get_user(regs->r7, sc->sc_regs+7); |
| 251 | err |= __get_user(regs->r8, sc->sc_regs+8); |
| 252 | err |= __get_user(sw->r9, sc->sc_regs+9); |
| 253 | err |= __get_user(sw->r10, sc->sc_regs+10); |
| 254 | err |= __get_user(sw->r11, sc->sc_regs+11); |
| 255 | err |= __get_user(sw->r12, sc->sc_regs+12); |
| 256 | err |= __get_user(sw->r13, sc->sc_regs+13); |
| 257 | err |= __get_user(sw->r14, sc->sc_regs+14); |
| 258 | err |= __get_user(sw->r15, sc->sc_regs+15); |
| 259 | err |= __get_user(regs->r16, sc->sc_regs+16); |
| 260 | err |= __get_user(regs->r17, sc->sc_regs+17); |
| 261 | err |= __get_user(regs->r18, sc->sc_regs+18); |
| 262 | err |= __get_user(regs->r19, sc->sc_regs+19); |
| 263 | err |= __get_user(regs->r20, sc->sc_regs+20); |
| 264 | err |= __get_user(regs->r21, sc->sc_regs+21); |
| 265 | err |= __get_user(regs->r22, sc->sc_regs+22); |
| 266 | err |= __get_user(regs->r23, sc->sc_regs+23); |
| 267 | err |= __get_user(regs->r24, sc->sc_regs+24); |
| 268 | err |= __get_user(regs->r25, sc->sc_regs+25); |
| 269 | err |= __get_user(regs->r26, sc->sc_regs+26); |
| 270 | err |= __get_user(regs->r27, sc->sc_regs+27); |
| 271 | err |= __get_user(regs->r28, sc->sc_regs+28); |
| 272 | err |= __get_user(regs->gp, sc->sc_regs+29); |
| 273 | err |= __get_user(usp, sc->sc_regs+30); |
| 274 | wrusp(usp); |
| 275 | |
| 276 | for (i = 0; i < 31; i++) |
| 277 | err |= __get_user(sw->fp[i], sc->sc_fpregs+i); |
| 278 | err |= __get_user(sw->fp[31], &sc->sc_fpcr); |
| 279 | |
| 280 | return err; |
| 281 | } |
| 282 | |
| 283 | /* Note that this syscall is also used by setcontext(3) to install |
| 284 | a given sigcontext. This because it's impossible to set *all* |
| 285 | registers and transfer control from userland. */ |
| 286 | |
| 287 | asmlinkage void |
| 288 | do_sigreturn(struct sigcontext __user *sc, struct pt_regs *regs, |
| 289 | struct switch_stack *sw) |
| 290 | { |
| 291 | sigset_t set; |
| 292 | |
| 293 | /* Verify that it's a good sigcontext before using it */ |
| 294 | if (!access_ok(VERIFY_READ, sc, sizeof(*sc))) |
| 295 | goto give_sigsegv; |
| 296 | if (__get_user(set.sig[0], &sc->sc_mask)) |
| 297 | goto give_sigsegv; |
| 298 | |
| 299 | sigdelsetmask(&set, ~_BLOCKABLE); |
| 300 | spin_lock_irq(¤t->sighand->siglock); |
| 301 | current->blocked = set; |
| 302 | recalc_sigpending(); |
| 303 | spin_unlock_irq(¤t->sighand->siglock); |
| 304 | |
| 305 | if (restore_sigcontext(sc, regs, sw)) |
| 306 | goto give_sigsegv; |
| 307 | |
| 308 | /* Send SIGTRAP if we're single-stepping: */ |
| 309 | if (ptrace_cancel_bpt (current)) { |
| 310 | siginfo_t info; |
| 311 | |
| 312 | info.si_signo = SIGTRAP; |
| 313 | info.si_errno = 0; |
| 314 | info.si_code = TRAP_BRKPT; |
| 315 | info.si_addr = (void __user *) regs->pc; |
| 316 | info.si_trapno = 0; |
| 317 | send_sig_info(SIGTRAP, &info, current); |
| 318 | } |
| 319 | return; |
| 320 | |
| 321 | give_sigsegv: |
| 322 | force_sig(SIGSEGV, current); |
| 323 | } |
| 324 | |
| 325 | asmlinkage void |
| 326 | do_rt_sigreturn(struct rt_sigframe __user *frame, struct pt_regs *regs, |
| 327 | struct switch_stack *sw) |
| 328 | { |
| 329 | sigset_t set; |
| 330 | |
| 331 | /* Verify that it's a good ucontext_t before using it */ |
| 332 | if (!access_ok(VERIFY_READ, &frame->uc, sizeof(frame->uc))) |
| 333 | goto give_sigsegv; |
| 334 | if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set))) |
| 335 | goto give_sigsegv; |
| 336 | |
| 337 | sigdelsetmask(&set, ~_BLOCKABLE); |
| 338 | spin_lock_irq(¤t->sighand->siglock); |
| 339 | current->blocked = set; |
| 340 | recalc_sigpending(); |
| 341 | spin_unlock_irq(¤t->sighand->siglock); |
| 342 | |
| 343 | if (restore_sigcontext(&frame->uc.uc_mcontext, regs, sw)) |
| 344 | goto give_sigsegv; |
| 345 | |
| 346 | /* Send SIGTRAP if we're single-stepping: */ |
| 347 | if (ptrace_cancel_bpt (current)) { |
| 348 | siginfo_t info; |
| 349 | |
| 350 | info.si_signo = SIGTRAP; |
| 351 | info.si_errno = 0; |
| 352 | info.si_code = TRAP_BRKPT; |
| 353 | info.si_addr = (void __user *) regs->pc; |
| 354 | info.si_trapno = 0; |
| 355 | send_sig_info(SIGTRAP, &info, current); |
| 356 | } |
| 357 | return; |
| 358 | |
| 359 | give_sigsegv: |
| 360 | force_sig(SIGSEGV, current); |
| 361 | } |
| 362 | |
| 363 | |
| 364 | /* |
| 365 | * Set up a signal frame. |
| 366 | */ |
| 367 | |
| 368 | static inline void __user * |
| 369 | get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size) |
| 370 | { |
Laurent MEYER | d09042d | 2006-06-23 02:05:36 -0700 | [diff] [blame] | 371 | if ((ka->sa.sa_flags & SA_ONSTACK) != 0 && ! sas_ss_flags(sp)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 372 | sp = current->sas_ss_sp + current->sas_ss_size; |
| 373 | |
| 374 | return (void __user *)((sp - frame_size) & -32ul); |
| 375 | } |
| 376 | |
| 377 | static long |
| 378 | setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs, |
| 379 | struct switch_stack *sw, unsigned long mask, unsigned long sp) |
| 380 | { |
| 381 | long i, err = 0; |
| 382 | |
| 383 | err |= __put_user(on_sig_stack((unsigned long)sc), &sc->sc_onstack); |
| 384 | err |= __put_user(mask, &sc->sc_mask); |
| 385 | err |= __put_user(regs->pc, &sc->sc_pc); |
| 386 | err |= __put_user(8, &sc->sc_ps); |
| 387 | |
| 388 | err |= __put_user(regs->r0 , sc->sc_regs+0); |
| 389 | err |= __put_user(regs->r1 , sc->sc_regs+1); |
| 390 | err |= __put_user(regs->r2 , sc->sc_regs+2); |
| 391 | err |= __put_user(regs->r3 , sc->sc_regs+3); |
| 392 | err |= __put_user(regs->r4 , sc->sc_regs+4); |
| 393 | err |= __put_user(regs->r5 , sc->sc_regs+5); |
| 394 | err |= __put_user(regs->r6 , sc->sc_regs+6); |
| 395 | err |= __put_user(regs->r7 , sc->sc_regs+7); |
| 396 | err |= __put_user(regs->r8 , sc->sc_regs+8); |
| 397 | err |= __put_user(sw->r9 , sc->sc_regs+9); |
| 398 | err |= __put_user(sw->r10 , sc->sc_regs+10); |
| 399 | err |= __put_user(sw->r11 , sc->sc_regs+11); |
| 400 | err |= __put_user(sw->r12 , sc->sc_regs+12); |
| 401 | err |= __put_user(sw->r13 , sc->sc_regs+13); |
| 402 | err |= __put_user(sw->r14 , sc->sc_regs+14); |
| 403 | err |= __put_user(sw->r15 , sc->sc_regs+15); |
| 404 | err |= __put_user(regs->r16, sc->sc_regs+16); |
| 405 | err |= __put_user(regs->r17, sc->sc_regs+17); |
| 406 | err |= __put_user(regs->r18, sc->sc_regs+18); |
| 407 | err |= __put_user(regs->r19, sc->sc_regs+19); |
| 408 | err |= __put_user(regs->r20, sc->sc_regs+20); |
| 409 | err |= __put_user(regs->r21, sc->sc_regs+21); |
| 410 | err |= __put_user(regs->r22, sc->sc_regs+22); |
| 411 | err |= __put_user(regs->r23, sc->sc_regs+23); |
| 412 | err |= __put_user(regs->r24, sc->sc_regs+24); |
| 413 | err |= __put_user(regs->r25, sc->sc_regs+25); |
| 414 | err |= __put_user(regs->r26, sc->sc_regs+26); |
| 415 | err |= __put_user(regs->r27, sc->sc_regs+27); |
| 416 | err |= __put_user(regs->r28, sc->sc_regs+28); |
| 417 | err |= __put_user(regs->gp , sc->sc_regs+29); |
| 418 | err |= __put_user(sp, sc->sc_regs+30); |
| 419 | err |= __put_user(0, sc->sc_regs+31); |
| 420 | |
| 421 | for (i = 0; i < 31; i++) |
| 422 | err |= __put_user(sw->fp[i], sc->sc_fpregs+i); |
| 423 | err |= __put_user(0, sc->sc_fpregs+31); |
| 424 | err |= __put_user(sw->fp[31], &sc->sc_fpcr); |
| 425 | |
| 426 | err |= __put_user(regs->trap_a0, &sc->sc_traparg_a0); |
| 427 | err |= __put_user(regs->trap_a1, &sc->sc_traparg_a1); |
| 428 | err |= __put_user(regs->trap_a2, &sc->sc_traparg_a2); |
| 429 | |
| 430 | return err; |
| 431 | } |
| 432 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 433 | static int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | setup_frame(int sig, struct k_sigaction *ka, sigset_t *set, |
| 435 | struct pt_regs *regs, struct switch_stack * sw) |
| 436 | { |
| 437 | unsigned long oldsp, r26, err = 0; |
| 438 | struct sigframe __user *frame; |
| 439 | |
| 440 | oldsp = rdusp(); |
| 441 | frame = get_sigframe(ka, oldsp, sizeof(*frame)); |
| 442 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| 443 | goto give_sigsegv; |
| 444 | |
| 445 | err |= setup_sigcontext(&frame->sc, regs, sw, set->sig[0], oldsp); |
| 446 | if (err) |
| 447 | goto give_sigsegv; |
| 448 | |
| 449 | /* Set up to return from userspace. If provided, use a stub |
| 450 | already in userspace. */ |
| 451 | if (ka->ka_restorer) { |
| 452 | r26 = (unsigned long) ka->ka_restorer; |
| 453 | } else { |
| 454 | err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0); |
| 455 | err |= __put_user(INSN_LDI_R0+__NR_sigreturn, frame->retcode+1); |
| 456 | err |= __put_user(INSN_CALLSYS, frame->retcode+2); |
| 457 | imb(); |
| 458 | r26 = (unsigned long) frame->retcode; |
| 459 | } |
| 460 | |
| 461 | /* Check that everything was written properly. */ |
| 462 | if (err) |
| 463 | goto give_sigsegv; |
| 464 | |
| 465 | /* "Return" to the handler */ |
| 466 | regs->r26 = r26; |
| 467 | regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler; |
| 468 | regs->r16 = sig; /* a0: signal number */ |
| 469 | regs->r17 = 0; /* a1: exception code */ |
| 470 | regs->r18 = (unsigned long) &frame->sc; /* a2: sigcontext pointer */ |
| 471 | wrusp((unsigned long) frame); |
| 472 | |
| 473 | #if DEBUG_SIG |
| 474 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", |
| 475 | current->comm, current->pid, frame, regs->pc, regs->r26); |
| 476 | #endif |
| 477 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 478 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 479 | |
| 480 | give_sigsegv: |
| 481 | force_sigsegv(sig, current); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 482 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | } |
| 484 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 485 | static int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 486 | setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, |
| 487 | sigset_t *set, struct pt_regs *regs, struct switch_stack * sw) |
| 488 | { |
| 489 | unsigned long oldsp, r26, err = 0; |
| 490 | struct rt_sigframe __user *frame; |
| 491 | |
| 492 | oldsp = rdusp(); |
| 493 | frame = get_sigframe(ka, oldsp, sizeof(*frame)); |
| 494 | if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) |
| 495 | goto give_sigsegv; |
| 496 | |
| 497 | err |= copy_siginfo_to_user(&frame->info, info); |
| 498 | |
| 499 | /* Create the ucontext. */ |
| 500 | err |= __put_user(0, &frame->uc.uc_flags); |
| 501 | err |= __put_user(0, &frame->uc.uc_link); |
| 502 | err |= __put_user(set->sig[0], &frame->uc.uc_osf_sigmask); |
| 503 | err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); |
| 504 | err |= __put_user(sas_ss_flags(oldsp), &frame->uc.uc_stack.ss_flags); |
| 505 | err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); |
| 506 | err |= setup_sigcontext(&frame->uc.uc_mcontext, regs, sw, |
| 507 | set->sig[0], oldsp); |
| 508 | err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); |
| 509 | if (err) |
| 510 | goto give_sigsegv; |
| 511 | |
| 512 | /* Set up to return from userspace. If provided, use a stub |
| 513 | already in userspace. */ |
| 514 | if (ka->ka_restorer) { |
| 515 | r26 = (unsigned long) ka->ka_restorer; |
| 516 | } else { |
| 517 | err |= __put_user(INSN_MOV_R30_R16, frame->retcode+0); |
| 518 | err |= __put_user(INSN_LDI_R0+__NR_rt_sigreturn, |
| 519 | frame->retcode+1); |
| 520 | err |= __put_user(INSN_CALLSYS, frame->retcode+2); |
| 521 | imb(); |
| 522 | r26 = (unsigned long) frame->retcode; |
| 523 | } |
| 524 | |
| 525 | if (err) |
| 526 | goto give_sigsegv; |
| 527 | |
| 528 | /* "Return" to the handler */ |
| 529 | regs->r26 = r26; |
| 530 | regs->r27 = regs->pc = (unsigned long) ka->sa.sa_handler; |
| 531 | regs->r16 = sig; /* a0: signal number */ |
| 532 | regs->r17 = (unsigned long) &frame->info; /* a1: siginfo pointer */ |
| 533 | regs->r18 = (unsigned long) &frame->uc; /* a2: ucontext pointer */ |
| 534 | wrusp((unsigned long) frame); |
| 535 | |
| 536 | #if DEBUG_SIG |
| 537 | printk("SIG deliver (%s:%d): sp=%p pc=%p ra=%p\n", |
| 538 | current->comm, current->pid, frame, regs->pc, regs->r26); |
| 539 | #endif |
| 540 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 541 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 542 | |
| 543 | give_sigsegv: |
| 544 | force_sigsegv(sig, current); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 545 | return -EFAULT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 546 | } |
| 547 | |
| 548 | |
| 549 | /* |
| 550 | * OK, we're invoking a handler. |
| 551 | */ |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 552 | static inline int |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 553 | handle_signal(int sig, struct k_sigaction *ka, siginfo_t *info, |
| 554 | sigset_t *oldset, struct pt_regs * regs, struct switch_stack *sw) |
| 555 | { |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 556 | int ret; |
| 557 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 558 | if (ka->sa.sa_flags & SA_SIGINFO) |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 559 | ret = setup_rt_frame(sig, ka, info, oldset, regs, sw); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 560 | else |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 561 | ret = setup_frame(sig, ka, oldset, regs, sw); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 563 | if (ret == 0) { |
| 564 | spin_lock_irq(¤t->sighand->siglock); |
| 565 | sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); |
| 566 | if (!(ka->sa.sa_flags & SA_NODEFER)) |
| 567 | sigaddset(¤t->blocked,sig); |
| 568 | recalc_sigpending(); |
| 569 | spin_unlock_irq(¤t->sighand->siglock); |
| 570 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 571 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 572 | return ret; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | } |
| 574 | |
| 575 | static inline void |
| 576 | syscall_restart(unsigned long r0, unsigned long r19, |
| 577 | struct pt_regs *regs, struct k_sigaction *ka) |
| 578 | { |
| 579 | switch (regs->r0) { |
| 580 | case ERESTARTSYS: |
| 581 | if (!(ka->sa.sa_flags & SA_RESTART)) { |
| 582 | case ERESTARTNOHAND: |
| 583 | regs->r0 = EINTR; |
| 584 | break; |
| 585 | } |
| 586 | /* fallthrough */ |
| 587 | case ERESTARTNOINTR: |
| 588 | regs->r0 = r0; /* reset v0 and a3 and replay syscall */ |
| 589 | regs->r19 = r19; |
| 590 | regs->pc -= 4; |
| 591 | break; |
| 592 | case ERESTART_RESTARTBLOCK: |
| 593 | current_thread_info()->restart_block.fn = do_no_restart_syscall; |
| 594 | regs->r0 = EINTR; |
| 595 | break; |
| 596 | } |
| 597 | } |
| 598 | |
| 599 | |
| 600 | /* |
| 601 | * Note that 'init' is a special process: it doesn't get signals it doesn't |
| 602 | * want to handle. Thus you cannot kill init even with a SIGKILL even by |
| 603 | * mistake. |
| 604 | * |
| 605 | * Note that we go through the signals twice: once to check the signals that |
| 606 | * the kernel can handle, and then we build all the user-level signal handling |
| 607 | * stack-frames in one go after that. |
| 608 | * |
| 609 | * "r0" and "r19" are the registers we need to restore for system call |
| 610 | * restart. "r0" is also used as an indicator whether we can restart at |
| 611 | * all (if we get here from anything but a syscall return, it will be 0) |
| 612 | */ |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 613 | static void |
| 614 | do_signal(struct pt_regs * regs, struct switch_stack * sw, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 615 | unsigned long r0, unsigned long r19) |
| 616 | { |
| 617 | siginfo_t info; |
| 618 | int signr; |
| 619 | unsigned long single_stepping = ptrace_cancel_bpt(current); |
| 620 | struct k_sigaction ka; |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 621 | sigset_t *oldset; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 622 | |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 623 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
| 624 | oldset = ¤t->saved_sigmask; |
| 625 | else |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 626 | oldset = ¤t->blocked; |
| 627 | |
| 628 | /* This lets the debugger run, ... */ |
| 629 | signr = get_signal_to_deliver(&info, &ka, regs, NULL); |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 630 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | /* ... so re-check the single stepping. */ |
| 632 | single_stepping |= ptrace_cancel_bpt(current); |
| 633 | |
| 634 | if (signr > 0) { |
| 635 | /* Whee! Actually deliver the signal. */ |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 636 | if (r0) |
| 637 | syscall_restart(r0, r19, regs, &ka); |
| 638 | if (handle_signal(signr, &ka, &info, oldset, regs, sw) == 0) { |
| 639 | /* A signal was successfully delivered, and the |
| 640 | saved sigmask was stored on the signal frame, |
| 641 | and will be restored by sigreturn. So we can |
| 642 | simply clear the restore sigmask flag. */ |
| 643 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) |
| 644 | clear_thread_flag(TIF_RESTORE_SIGMASK); |
| 645 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 646 | if (single_stepping) |
| 647 | ptrace_set_bpt(current); /* re-set bpt */ |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 648 | return; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 649 | } |
| 650 | |
| 651 | if (r0) { |
| 652 | switch (regs->r0) { |
| 653 | case ERESTARTNOHAND: |
| 654 | case ERESTARTSYS: |
| 655 | case ERESTARTNOINTR: |
| 656 | /* Reset v0 and a3 and replay syscall. */ |
| 657 | regs->r0 = r0; |
| 658 | regs->r19 = r19; |
| 659 | regs->pc -= 4; |
| 660 | break; |
| 661 | case ERESTART_RESTARTBLOCK: |
| 662 | /* Force v0 to the restart syscall and reply. */ |
| 663 | regs->r0 = __NR_restart_syscall; |
| 664 | regs->pc -= 4; |
| 665 | break; |
| 666 | } |
| 667 | } |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 668 | |
| 669 | /* If there's no signal to deliver, we just restore the saved mask. */ |
| 670 | if (test_thread_flag(TIF_RESTORE_SIGMASK)) { |
| 671 | clear_thread_flag(TIF_RESTORE_SIGMASK); |
| 672 | sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); |
| 673 | } |
| 674 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 675 | if (single_stepping) |
| 676 | ptrace_set_bpt(current); /* re-set breakpoint */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 677 | } |
| 678 | |
| 679 | void |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 680 | do_notify_resume(struct pt_regs *regs, struct switch_stack *sw, |
| 681 | unsigned long thread_info_flags, |
| 682 | unsigned long r0, unsigned long r19) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | { |
Richard Henderson | b927b3e | 2007-05-29 16:03:28 -0700 | [diff] [blame] | 684 | if (thread_info_flags & (_TIF_SIGPENDING | _TIF_RESTORE_SIGMASK)) |
| 685 | do_signal(regs, sw, r0, r19); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | } |