1 #ifndef _LINUX_SIGNAL_H 2 #define _LINUX_SIGNAL_H 3 4 #include <linux/list.h> 5 #include <uapi/linux/signal.h> 6 7 struct task_struct; 8 9 /* for sysctl */ 10 extern int print_fatal_signals; 11 /* 12 * Real Time signals may be queued. 13 */ 14 15 struct sigqueue { 16 struct list_head list; 17 int flags; 18 siginfo_t info; 19 struct user_struct *user; 20 }; 21 22 /* flags values. */ 23 #define SIGQUEUE_PREALLOC 1 24 25 struct sigpending { 26 struct list_head list; 27 sigset_t signal; 28 }; 29 30 /* 31 * Define some primitives to manipulate sigset_t. 32 */ 33 34 #ifndef __HAVE_ARCH_SIG_BITOPS 35 #include <linux/bitops.h> 36 37 /* We don't use <linux/bitops.h> for these because there is no need to 38 be atomic. */ 39 static inline void sigaddset(sigset_t *set, int _sig) 40 { 41 unsigned long sig = _sig - 1; 42 if (_NSIG_WORDS == 1) 43 set->sig[0] |= 1UL << sig; 44 else 45 set->sig[sig / _NSIG_BPW] |= 1UL << (sig % _NSIG_BPW); 46 } 47 48 static inline void sigdelset(sigset_t *set, int _sig) 49 { 50 unsigned long sig = _sig - 1; 51 if (_NSIG_WORDS == 1) 52 set->sig[0] &= ~(1UL << sig); 53 else 54 set->sig[sig / _NSIG_BPW] &= ~(1UL << (sig % _NSIG_BPW)); 55 } 56 57 static inline int sigismember(sigset_t *set, int _sig) 58 { 59 unsigned long sig = _sig - 1; 60 if (_NSIG_WORDS == 1) 61 return 1 & (set->sig[0] >> sig); 62 else 63 return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW)); 64 } 65 66 #endif /* __HAVE_ARCH_SIG_BITOPS */ 67 68 static inline int sigisemptyset(sigset_t *set) 69 { 70 extern void _NSIG_WORDS_is_unsupported_size(void); 71 switch (_NSIG_WORDS) { 72 case 4: 73 return (set->sig[3] | set->sig[2] | 74 set->sig[1] | set->sig[0]) == 0; 75 case 2: 76 return (set->sig[1] | set->sig[0]) == 0; 77 case 1: 78 return set->sig[0] == 0; 79 default: 80 _NSIG_WORDS_is_unsupported_size(); 81 return 0; 82 } 83 } 84 85 #define sigmask(sig) (1UL << ((sig) - 1)) 86 87 #ifndef __HAVE_ARCH_SIG_SETOPS 88 #include <linux/string.h> 89 90 #define _SIG_SET_BINOP(name, op) \ 91 static inline void name(sigset_t *r, const sigset_t *a, const sigset_t *b) \ 92 { \ 93 extern void _NSIG_WORDS_is_unsupported_size(void); \ 94 unsigned long a0, a1, a2, a3, b0, b1, b2, b3; \ 95 \ 96 switch (_NSIG_WORDS) { \ 97 case 4: \ 98 a3 = a->sig[3]; a2 = a->sig[2]; \ 99 b3 = b->sig[3]; b2 = b->sig[2]; \ 100 r->sig[3] = op(a3, b3); \ 101 r->sig[2] = op(a2, b2); \ 102 case 2: \ 103 a1 = a->sig[1]; b1 = b->sig[1]; \ 104 r->sig[1] = op(a1, b1); \ 105 case 1: \ 106 a0 = a->sig[0]; b0 = b->sig[0]; \ 107 r->sig[0] = op(a0, b0); \ 108 break; \ 109 default: \ 110 _NSIG_WORDS_is_unsupported_size(); \ 111 } \ 112 } 113 114 #define _sig_or(x,y) ((x) | (y)) 115 _SIG_SET_BINOP(sigorsets, _sig_or) 116 117 #define _sig_and(x,y) ((x) & (y)) 118 _SIG_SET_BINOP(sigandsets, _sig_and) 119 120 #define _sig_andn(x,y) ((x) & ~(y)) 121 _SIG_SET_BINOP(sigandnsets, _sig_andn) 122 123 #undef _SIG_SET_BINOP 124 #undef _sig_or 125 #undef _sig_and 126 #undef _sig_andn 127 128 #define _SIG_SET_OP(name, op) \ 129 static inline void name(sigset_t *set) \ 130 { \ 131 extern void _NSIG_WORDS_is_unsupported_size(void); \ 132 \ 133 switch (_NSIG_WORDS) { \ 134 case 4: set->sig[3] = op(set->sig[3]); \ 135 set->sig[2] = op(set->sig[2]); \ 136 case 2: set->sig[1] = op(set->sig[1]); \ 137 case 1: set->sig[0] = op(set->sig[0]); \ 138 break; \ 139 default: \ 140 _NSIG_WORDS_is_unsupported_size(); \ 141 } \ 142 } 143 144 #define _sig_not(x) (~(x)) 145 _SIG_SET_OP(signotset, _sig_not) 146 147 #undef _SIG_SET_OP 148 #undef _sig_not 149 150 static inline void sigemptyset(sigset_t *set) 151 { 152 switch (_NSIG_WORDS) { 153 default: 154 memset(set, 0, sizeof(sigset_t)); 155 break; 156 case 2: set->sig[1] = 0; 157 case 1: set->sig[0] = 0; 158 break; 159 } 160 } 161 162 static inline void sigfillset(sigset_t *set) 163 { 164 switch (_NSIG_WORDS) { 165 default: 166 memset(set, -1, sizeof(sigset_t)); 167 break; 168 case 2: set->sig[1] = -1; 169 case 1: set->sig[0] = -1; 170 break; 171 } 172 } 173 174 /* Some extensions for manipulating the low 32 signals in particular. */ 175 176 static inline void sigaddsetmask(sigset_t *set, unsigned long mask) 177 { 178 set->sig[0] |= mask; 179 } 180 181 static inline void sigdelsetmask(sigset_t *set, unsigned long mask) 182 { 183 set->sig[0] &= ~mask; 184 } 185 186 static inline int sigtestsetmask(sigset_t *set, unsigned long mask) 187 { 188 return (set->sig[0] & mask) != 0; 189 } 190 191 static inline void siginitset(sigset_t *set, unsigned long mask) 192 { 193 set->sig[0] = mask; 194 switch (_NSIG_WORDS) { 195 default: 196 memset(&set->sig[1], 0, sizeof(long)*(_NSIG_WORDS-1)); 197 break; 198 case 2: set->sig[1] = 0; 199 case 1: ; 200 } 201 } 202 203 static inline void siginitsetinv(sigset_t *set, unsigned long mask) 204 { 205 set->sig[0] = ~mask; 206 switch (_NSIG_WORDS) { 207 default: 208 memset(&set->sig[1], -1, sizeof(long)*(_NSIG_WORDS-1)); 209 break; 210 case 2: set->sig[1] = -1; 211 case 1: ; 212 } 213 } 214 215 #endif /* __HAVE_ARCH_SIG_SETOPS */ 216 217 static inline void init_sigpending(struct sigpending *sig) 218 { 219 sigemptyset(&sig->signal); 220 INIT_LIST_HEAD(&sig->list); 221 } 222 223 extern void flush_sigqueue(struct sigpending *queue); 224 225 /* Test if 'sig' is valid signal. Use this instead of testing _NSIG directly */ 226 static inline int valid_signal(unsigned long sig) 227 { 228 return sig <= _NSIG ? 1 : 0; 229 } 230 231 struct timespec; 232 struct pt_regs; 233 234 extern int next_signal(struct sigpending *pending, sigset_t *mask); 235 extern int do_send_sig_info(int sig, struct siginfo *info, 236 struct task_struct *p, bool group); 237 extern int group_send_sig_info(int sig, struct siginfo *info, struct task_struct *p); 238 extern int __group_send_sig_info(int, struct siginfo *, struct task_struct *); 239 extern int do_sigtimedwait(const sigset_t *, siginfo_t *, 240 const struct timespec *); 241 extern int sigprocmask(int, sigset_t *, sigset_t *); 242 extern void set_current_blocked(sigset_t *); 243 extern void __set_current_blocked(const sigset_t *); 244 extern int show_unhandled_signals; 245 extern int sigsuspend(sigset_t *); 246 247 struct sigaction { 248 #ifndef __ARCH_HAS_IRIX_SIGACTION 249 __sighandler_t sa_handler; 250 unsigned long sa_flags; 251 #else 252 unsigned int sa_flags; 253 __sighandler_t sa_handler; 254 #endif 255 #ifdef __ARCH_HAS_SA_RESTORER 256 __sigrestore_t sa_restorer; 257 #endif 258 sigset_t sa_mask; /* mask last for extensibility */ 259 }; 260 261 struct k_sigaction { 262 struct sigaction sa; 263 #ifdef __ARCH_HAS_KA_RESTORER 264 __sigrestore_t ka_restorer; 265 #endif 266 }; 267 268 #ifdef CONFIG_OLD_SIGACTION 269 struct old_sigaction { 270 __sighandler_t sa_handler; 271 old_sigset_t sa_mask; 272 unsigned long sa_flags; 273 __sigrestore_t sa_restorer; 274 }; 275 #endif 276 277 struct ksignal { 278 struct k_sigaction ka; 279 siginfo_t info; 280 int sig; 281 }; 282 283 extern int get_signal_to_deliver(siginfo_t *info, struct k_sigaction *return_ka, struct pt_regs *regs, void *cookie); 284 extern void signal_setup_done(int failed, struct ksignal *ksig, int stepping); 285 extern void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka, struct pt_regs *regs, int stepping); 286 extern void exit_signals(struct task_struct *tsk); 287 extern void kernel_sigaction(int, __sighandler_t); 288 289 static inline void allow_signal(int sig) 290 { 291 /* 292 * Kernel threads handle their own signals. Let the signal code 293 * know it'll be handled, so that they don't get converted to 294 * SIGKILL or just silently dropped. 295 */ 296 kernel_sigaction(sig, (__force __sighandler_t)2); 297 } 298 299 static inline void disallow_signal(int sig) 300 { 301 kernel_sigaction(sig, SIG_IGN); 302 } 303 304 /* 305 * Eventually that'll replace get_signal_to_deliver(); macro for now, 306 * to avoid nastiness with include order. 307 */ 308 #define get_signal(ksig) \ 309 ({ \ 310 struct ksignal *p = (ksig); \ 311 p->sig = get_signal_to_deliver(&p->info, &p->ka, \ 312 signal_pt_regs(), NULL);\ 313 p->sig > 0; \ 314 }) 315 316 extern struct kmem_cache *sighand_cachep; 317 318 int unhandled_signal(struct task_struct *tsk, int sig); 319 320 /* 321 * In POSIX a signal is sent either to a specific thread (Linux task) 322 * or to the process as a whole (Linux thread group). How the signal 323 * is sent determines whether it's to one thread or the whole group, 324 * which determines which signal mask(s) are involved in blocking it 325 * from being delivered until later. When the signal is delivered, 326 * either it's caught or ignored by a user handler or it has a default 327 * effect that applies to the whole thread group (POSIX process). 328 * 329 * The possible effects an unblocked signal set to SIG_DFL can have are: 330 * ignore - Nothing Happens 331 * terminate - kill the process, i.e. all threads in the group, 332 * similar to exit_group. The group leader (only) reports 333 * WIFSIGNALED status to its parent. 334 * coredump - write a core dump file describing all threads using 335 * the same mm and then kill all those threads 336 * stop - stop all the threads in the group, i.e. TASK_STOPPED state 337 * 338 * SIGKILL and SIGSTOP cannot be caught, blocked, or ignored. 339 * Other signals when not blocked and set to SIG_DFL behaves as follows. 340 * The job control signals also have other special effects. 341 * 342 * +--------------------+------------------+ 343 * | POSIX signal | default action | 344 * +--------------------+------------------+ 345 * | SIGHUP | terminate | 346 * | SIGINT | terminate | 347 * | SIGQUIT | coredump | 348 * | SIGILL | coredump | 349 * | SIGTRAP | coredump | 350 * | SIGABRT/SIGIOT | coredump | 351 * | SIGBUS | coredump | 352 * | SIGFPE | coredump | 353 * | SIGKILL | terminate(+) | 354 * | SIGUSR1 | terminate | 355 * | SIGSEGV | coredump | 356 * | SIGUSR2 | terminate | 357 * | SIGPIPE | terminate | 358 * | SIGALRM | terminate | 359 * | SIGTERM | terminate | 360 * | SIGCHLD | ignore | 361 * | SIGCONT | ignore(*) | 362 * | SIGSTOP | stop(*)(+) | 363 * | SIGTSTP | stop(*) | 364 * | SIGTTIN | stop(*) | 365 * | SIGTTOU | stop(*) | 366 * | SIGURG | ignore | 367 * | SIGXCPU | coredump | 368 * | SIGXFSZ | coredump | 369 * | SIGVTALRM | terminate | 370 * | SIGPROF | terminate | 371 * | SIGPOLL/SIGIO | terminate | 372 * | SIGSYS/SIGUNUSED | coredump | 373 * | SIGSTKFLT | terminate | 374 * | SIGWINCH | ignore | 375 * | SIGPWR | terminate | 376 * | SIGRTMIN-SIGRTMAX | terminate | 377 * +--------------------+------------------+ 378 * | non-POSIX signal | default action | 379 * +--------------------+------------------+ 380 * | SIGEMT | coredump | 381 * +--------------------+------------------+ 382 * 383 * (+) For SIGKILL and SIGSTOP the action is "always", not just "default". 384 * (*) Special job control effects: 385 * When SIGCONT is sent, it resumes the process (all threads in the group) 386 * from TASK_STOPPED state and also clears any pending/queued stop signals 387 * (any of those marked with "stop(*)"). This happens regardless of blocking, 388 * catching, or ignoring SIGCONT. When any stop signal is sent, it clears 389 * any pending/queued SIGCONT signals; this happens regardless of blocking, 390 * catching, or ignored the stop signal, though (except for SIGSTOP) the 391 * default action of stopping the process may happen later or never. 392 */ 393 394 #ifdef SIGEMT 395 #define SIGEMT_MASK rt_sigmask(SIGEMT) 396 #else 397 #define SIGEMT_MASK 0 398 #endif 399 400 #if SIGRTMIN > BITS_PER_LONG 401 #define rt_sigmask(sig) (1ULL << ((sig)-1)) 402 #else 403 #define rt_sigmask(sig) sigmask(sig) 404 #endif 405 #define siginmask(sig, mask) (rt_sigmask(sig) & (mask)) 406 407 #define SIG_KERNEL_ONLY_MASK (\ 408 rt_sigmask(SIGKILL) | rt_sigmask(SIGSTOP)) 409 410 #define SIG_KERNEL_STOP_MASK (\ 411 rt_sigmask(SIGSTOP) | rt_sigmask(SIGTSTP) | \ 412 rt_sigmask(SIGTTIN) | rt_sigmask(SIGTTOU) ) 413 414 #define SIG_KERNEL_COREDUMP_MASK (\ 415 rt_sigmask(SIGQUIT) | rt_sigmask(SIGILL) | \ 416 rt_sigmask(SIGTRAP) | rt_sigmask(SIGABRT) | \ 417 rt_sigmask(SIGFPE) | rt_sigmask(SIGSEGV) | \ 418 rt_sigmask(SIGBUS) | rt_sigmask(SIGSYS) | \ 419 rt_sigmask(SIGXCPU) | rt_sigmask(SIGXFSZ) | \ 420 SIGEMT_MASK ) 421 422 #define SIG_KERNEL_IGNORE_MASK (\ 423 rt_sigmask(SIGCONT) | rt_sigmask(SIGCHLD) | \ 424 rt_sigmask(SIGWINCH) | rt_sigmask(SIGURG) ) 425 426 #define sig_kernel_only(sig) \ 427 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_ONLY_MASK)) 428 #define sig_kernel_coredump(sig) \ 429 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_COREDUMP_MASK)) 430 #define sig_kernel_ignore(sig) \ 431 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_IGNORE_MASK)) 432 #define sig_kernel_stop(sig) \ 433 (((sig) < SIGRTMIN) && siginmask(sig, SIG_KERNEL_STOP_MASK)) 434 435 #define sig_user_defined(t, signr) \ 436 (((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_DFL) && \ 437 ((t)->sighand->action[(signr)-1].sa.sa_handler != SIG_IGN)) 438 439 #define sig_fatal(t, signr) \ 440 (!siginmask(signr, SIG_KERNEL_IGNORE_MASK|SIG_KERNEL_STOP_MASK) && \ 441 (t)->sighand->action[(signr)-1].sa.sa_handler == SIG_DFL) 442 443 void signals_init(void); 444 445 int restore_altstack(const stack_t __user *); 446 int __save_altstack(stack_t __user *, unsigned long); 447 448 #define save_altstack_ex(uss, sp) do { \ 449 stack_t __user *__uss = uss; \ 450 struct task_struct *t = current; \ 451 put_user_ex((void __user *)t->sas_ss_sp, &__uss->ss_sp); \ 452 put_user_ex(sas_ss_flags(sp), &__uss->ss_flags); \ 453 put_user_ex(t->sas_ss_size, &__uss->ss_size); \ 454 } while (0); 455 456 #ifdef CONFIG_PROC_FS 457 struct seq_file; 458 extern void render_sigset_t(struct seq_file *, const char *, sigset_t *); 459 #endif 460 461 #endif /* _LINUX_SIGNAL_H */ 462