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TOMOYO Linux Cross Reference
Linux/include/linux/sched/signal.h

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  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 #ifndef _LINUX_SCHED_SIGNAL_H
  3 #define _LINUX_SCHED_SIGNAL_H
  4 
  5 #include <linux/rculist.h>
  6 #include <linux/signal.h>
  7 #include <linux/sched.h>
  8 #include <linux/sched/jobctl.h>
  9 #include <linux/sched/task.h>
 10 #include <linux/cred.h>
 11 
 12 /*
 13  * Types defining task->signal and task->sighand and APIs using them:
 14  */
 15 
 16 struct sighand_struct {
 17         atomic_t                count;
 18         struct k_sigaction      action[_NSIG];
 19         spinlock_t              siglock;
 20         wait_queue_head_t       signalfd_wqh;
 21 };
 22 
 23 /*
 24  * Per-process accounting stats:
 25  */
 26 struct pacct_struct {
 27         int                     ac_flag;
 28         long                    ac_exitcode;
 29         unsigned long           ac_mem;
 30         u64                     ac_utime, ac_stime;
 31         unsigned long           ac_minflt, ac_majflt;
 32 };
 33 
 34 struct cpu_itimer {
 35         u64 expires;
 36         u64 incr;
 37 };
 38 
 39 /*
 40  * This is the atomic variant of task_cputime, which can be used for
 41  * storing and updating task_cputime statistics without locking.
 42  */
 43 struct task_cputime_atomic {
 44         atomic64_t utime;
 45         atomic64_t stime;
 46         atomic64_t sum_exec_runtime;
 47 };
 48 
 49 #define INIT_CPUTIME_ATOMIC \
 50         (struct task_cputime_atomic) {                          \
 51                 .utime = ATOMIC64_INIT(0),                      \
 52                 .stime = ATOMIC64_INIT(0),                      \
 53                 .sum_exec_runtime = ATOMIC64_INIT(0),           \
 54         }
 55 /**
 56  * struct thread_group_cputimer - thread group interval timer counts
 57  * @cputime_atomic:     atomic thread group interval timers.
 58  * @running:            true when there are timers running and
 59  *                      @cputime_atomic receives updates.
 60  * @checking_timer:     true when a thread in the group is in the
 61  *                      process of checking for thread group timers.
 62  *
 63  * This structure contains the version of task_cputime, above, that is
 64  * used for thread group CPU timer calculations.
 65  */
 66 struct thread_group_cputimer {
 67         struct task_cputime_atomic cputime_atomic;
 68         bool running;
 69         bool checking_timer;
 70 };
 71 
 72 struct multiprocess_signals {
 73         sigset_t signal;
 74         struct hlist_node node;
 75 };
 76 
 77 /*
 78  * NOTE! "signal_struct" does not have its own
 79  * locking, because a shared signal_struct always
 80  * implies a shared sighand_struct, so locking
 81  * sighand_struct is always a proper superset of
 82  * the locking of signal_struct.
 83  */
 84 struct signal_struct {
 85         atomic_t                sigcnt;
 86         atomic_t                live;
 87         int                     nr_threads;
 88         struct list_head        thread_head;
 89 
 90         wait_queue_head_t       wait_chldexit;  /* for wait4() */
 91 
 92         /* current thread group signal load-balancing target: */
 93         struct task_struct      *curr_target;
 94 
 95         /* shared signal handling: */
 96         struct sigpending       shared_pending;
 97 
 98         /* For collecting multiprocess signals during fork */
 99         struct hlist_head       multiprocess;
100 
101         /* thread group exit support */
102         int                     group_exit_code;
103         /* overloaded:
104          * - notify group_exit_task when ->count is equal to notify_count
105          * - everyone except group_exit_task is stopped during signal delivery
106          *   of fatal signals, group_exit_task processes the signal.
107          */
108         int                     notify_count;
109         struct task_struct      *group_exit_task;
110 
111         /* thread group stop support, overloads group_exit_code too */
112         int                     group_stop_count;
113         unsigned int            flags; /* see SIGNAL_* flags below */
114 
115         /*
116          * PR_SET_CHILD_SUBREAPER marks a process, like a service
117          * manager, to re-parent orphan (double-forking) child processes
118          * to this process instead of 'init'. The service manager is
119          * able to receive SIGCHLD signals and is able to investigate
120          * the process until it calls wait(). All children of this
121          * process will inherit a flag if they should look for a
122          * child_subreaper process at exit.
123          */
124         unsigned int            is_child_subreaper:1;
125         unsigned int            has_child_subreaper:1;
126 
127 #ifdef CONFIG_POSIX_TIMERS
128 
129         /* POSIX.1b Interval Timers */
130         int                     posix_timer_id;
131         struct list_head        posix_timers;
132 
133         /* ITIMER_REAL timer for the process */
134         struct hrtimer real_timer;
135         ktime_t it_real_incr;
136 
137         /*
138          * ITIMER_PROF and ITIMER_VIRTUAL timers for the process, we use
139          * CPUCLOCK_PROF and CPUCLOCK_VIRT for indexing array as these
140          * values are defined to 0 and 1 respectively
141          */
142         struct cpu_itimer it[2];
143 
144         /*
145          * Thread group totals for process CPU timers.
146          * See thread_group_cputimer(), et al, for details.
147          */
148         struct thread_group_cputimer cputimer;
149 
150         /* Earliest-expiration cache. */
151         struct task_cputime cputime_expires;
152 
153         struct list_head cpu_timers[3];
154 
155 #endif
156 
157         /* PID/PID hash table linkage. */
158         struct pid *pids[PIDTYPE_MAX];
159 
160 #ifdef CONFIG_NO_HZ_FULL
161         atomic_t tick_dep_mask;
162 #endif
163 
164         struct pid *tty_old_pgrp;
165 
166         /* boolean value for session group leader */
167         int leader;
168 
169         struct tty_struct *tty; /* NULL if no tty */
170 
171 #ifdef CONFIG_SCHED_AUTOGROUP
172         struct autogroup *autogroup;
173 #endif
174         /*
175          * Cumulative resource counters for dead threads in the group,
176          * and for reaped dead child processes forked by this group.
177          * Live threads maintain their own counters and add to these
178          * in __exit_signal, except for the group leader.
179          */
180         seqlock_t stats_lock;
181         u64 utime, stime, cutime, cstime;
182         u64 gtime;
183         u64 cgtime;
184         struct prev_cputime prev_cputime;
185         unsigned long nvcsw, nivcsw, cnvcsw, cnivcsw;
186         unsigned long min_flt, maj_flt, cmin_flt, cmaj_flt;
187         unsigned long inblock, oublock, cinblock, coublock;
188         unsigned long maxrss, cmaxrss;
189         struct task_io_accounting ioac;
190 
191         /*
192          * Cumulative ns of schedule CPU time fo dead threads in the
193          * group, not including a zombie group leader, (This only differs
194          * from jiffies_to_ns(utime + stime) if sched_clock uses something
195          * other than jiffies.)
196          */
197         unsigned long long sum_sched_runtime;
198 
199         /*
200          * We don't bother to synchronize most readers of this at all,
201          * because there is no reader checking a limit that actually needs
202          * to get both rlim_cur and rlim_max atomically, and either one
203          * alone is a single word that can safely be read normally.
204          * getrlimit/setrlimit use task_lock(current->group_leader) to
205          * protect this instead of the siglock, because they really
206          * have no need to disable irqs.
207          */
208         struct rlimit rlim[RLIM_NLIMITS];
209 
210 #ifdef CONFIG_BSD_PROCESS_ACCT
211         struct pacct_struct pacct;      /* per-process accounting information */
212 #endif
213 #ifdef CONFIG_TASKSTATS
214         struct taskstats *stats;
215 #endif
216 #ifdef CONFIG_AUDIT
217         unsigned audit_tty;
218         struct tty_audit_buf *tty_audit_buf;
219 #endif
220 
221         /*
222          * Thread is the potential origin of an oom condition; kill first on
223          * oom
224          */
225         bool oom_flag_origin;
226         short oom_score_adj;            /* OOM kill score adjustment */
227         short oom_score_adj_min;        /* OOM kill score adjustment min value.
228                                          * Only settable by CAP_SYS_RESOURCE. */
229         struct mm_struct *oom_mm;       /* recorded mm when the thread group got
230                                          * killed by the oom killer */
231 
232         struct mutex cred_guard_mutex;  /* guard against foreign influences on
233                                          * credential calculations
234                                          * (notably. ptrace) */
235 } __randomize_layout;
236 
237 /*
238  * Bits in flags field of signal_struct.
239  */
240 #define SIGNAL_STOP_STOPPED     0x00000001 /* job control stop in effect */
241 #define SIGNAL_STOP_CONTINUED   0x00000002 /* SIGCONT since WCONTINUED reap */
242 #define SIGNAL_GROUP_EXIT       0x00000004 /* group exit in progress */
243 #define SIGNAL_GROUP_COREDUMP   0x00000008 /* coredump in progress */
244 /*
245  * Pending notifications to parent.
246  */
247 #define SIGNAL_CLD_STOPPED      0x00000010
248 #define SIGNAL_CLD_CONTINUED    0x00000020
249 #define SIGNAL_CLD_MASK         (SIGNAL_CLD_STOPPED|SIGNAL_CLD_CONTINUED)
250 
251 #define SIGNAL_UNKILLABLE       0x00000040 /* for init: ignore fatal signals */
252 
253 #define SIGNAL_STOP_MASK (SIGNAL_CLD_MASK | SIGNAL_STOP_STOPPED | \
254                           SIGNAL_STOP_CONTINUED)
255 
256 static inline void signal_set_stop_flags(struct signal_struct *sig,
257                                          unsigned int flags)
258 {
259         WARN_ON(sig->flags & (SIGNAL_GROUP_EXIT|SIGNAL_GROUP_COREDUMP));
260         sig->flags = (sig->flags & ~SIGNAL_STOP_MASK) | flags;
261 }
262 
263 /* If true, all threads except ->group_exit_task have pending SIGKILL */
264 static inline int signal_group_exit(const struct signal_struct *sig)
265 {
266         return  (sig->flags & SIGNAL_GROUP_EXIT) ||
267                 (sig->group_exit_task != NULL);
268 }
269 
270 extern void flush_signals(struct task_struct *);
271 extern void ignore_signals(struct task_struct *);
272 extern void flush_signal_handlers(struct task_struct *, int force_default);
273 extern int dequeue_signal(struct task_struct *tsk, sigset_t *mask, kernel_siginfo_t *info);
274 
275 static inline int kernel_dequeue_signal(void)
276 {
277         struct task_struct *tsk = current;
278         kernel_siginfo_t __info;
279         int ret;
280 
281         spin_lock_irq(&tsk->sighand->siglock);
282         ret = dequeue_signal(tsk, &tsk->blocked, &__info);
283         spin_unlock_irq(&tsk->sighand->siglock);
284 
285         return ret;
286 }
287 
288 static inline void kernel_signal_stop(void)
289 {
290         spin_lock_irq(&current->sighand->siglock);
291         if (current->jobctl & JOBCTL_STOP_DEQUEUED)
292                 set_special_state(TASK_STOPPED);
293         spin_unlock_irq(&current->sighand->siglock);
294 
295         schedule();
296 }
297 #ifdef __ARCH_SI_TRAPNO
298 # define ___ARCH_SI_TRAPNO(_a1) , _a1
299 #else
300 # define ___ARCH_SI_TRAPNO(_a1)
301 #endif
302 #ifdef __ia64__
303 # define ___ARCH_SI_IA64(_a1, _a2, _a3) , _a1, _a2, _a3
304 #else
305 # define ___ARCH_SI_IA64(_a1, _a2, _a3)
306 #endif
307 
308 int force_sig_fault(int sig, int code, void __user *addr
309         ___ARCH_SI_TRAPNO(int trapno)
310         ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
311         , struct task_struct *t);
312 int send_sig_fault(int sig, int code, void __user *addr
313         ___ARCH_SI_TRAPNO(int trapno)
314         ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
315         , struct task_struct *t);
316 
317 int force_sig_mceerr(int code, void __user *, short, struct task_struct *);
318 int send_sig_mceerr(int code, void __user *, short, struct task_struct *);
319 
320 int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper);
321 int force_sig_pkuerr(void __user *addr, u32 pkey);
322 
323 int force_sig_ptrace_errno_trap(int errno, void __user *addr);
324 
325 extern int send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
326 extern void force_sigsegv(int sig, struct task_struct *p);
327 extern int force_sig_info(int, struct kernel_siginfo *, struct task_struct *);
328 extern int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp);
329 extern int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid);
330 extern int kill_pid_info_as_cred(int, struct kernel_siginfo *, struct pid *,
331                                 const struct cred *);
332 extern int kill_pgrp(struct pid *pid, int sig, int priv);
333 extern int kill_pid(struct pid *pid, int sig, int priv);
334 extern __must_check bool do_notify_parent(struct task_struct *, int);
335 extern void __wake_up_parent(struct task_struct *p, struct task_struct *parent);
336 extern void force_sig(int, struct task_struct *);
337 extern int send_sig(int, struct task_struct *, int);
338 extern int zap_other_threads(struct task_struct *p);
339 extern struct sigqueue *sigqueue_alloc(void);
340 extern void sigqueue_free(struct sigqueue *);
341 extern int send_sigqueue(struct sigqueue *, struct pid *, enum pid_type);
342 extern int do_sigaction(int, struct k_sigaction *, struct k_sigaction *);
343 
344 static inline int restart_syscall(void)
345 {
346         set_tsk_thread_flag(current, TIF_SIGPENDING);
347         return -ERESTARTNOINTR;
348 }
349 
350 static inline int signal_pending(struct task_struct *p)
351 {
352         return unlikely(test_tsk_thread_flag(p,TIF_SIGPENDING));
353 }
354 
355 static inline int __fatal_signal_pending(struct task_struct *p)
356 {
357         return unlikely(sigismember(&p->pending.signal, SIGKILL));
358 }
359 
360 static inline int fatal_signal_pending(struct task_struct *p)
361 {
362         return signal_pending(p) && __fatal_signal_pending(p);
363 }
364 
365 static inline int signal_pending_state(long state, struct task_struct *p)
366 {
367         if (!(state & (TASK_INTERRUPTIBLE | TASK_WAKEKILL)))
368                 return 0;
369         if (!signal_pending(p))
370                 return 0;
371 
372         return (state & TASK_INTERRUPTIBLE) || __fatal_signal_pending(p);
373 }
374 
375 /*
376  * Reevaluate whether the task has signals pending delivery.
377  * Wake the task if so.
378  * This is required every time the blocked sigset_t changes.
379  * callers must hold sighand->siglock.
380  */
381 extern void recalc_sigpending_and_wake(struct task_struct *t);
382 extern void recalc_sigpending(void);
383 extern void calculate_sigpending(void);
384 
385 extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
386 
387 static inline void signal_wake_up(struct task_struct *t, bool resume)
388 {
389         signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
390 }
391 static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
392 {
393         signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
394 }
395 
396 void task_join_group_stop(struct task_struct *task);
397 
398 #ifdef TIF_RESTORE_SIGMASK
399 /*
400  * Legacy restore_sigmask accessors.  These are inefficient on
401  * SMP architectures because they require atomic operations.
402  */
403 
404 /**
405  * set_restore_sigmask() - make sure saved_sigmask processing gets done
406  *
407  * This sets TIF_RESTORE_SIGMASK and ensures that the arch signal code
408  * will run before returning to user mode, to process the flag.  For
409  * all callers, TIF_SIGPENDING is already set or it's no harm to set
410  * it.  TIF_RESTORE_SIGMASK need not be in the set of bits that the
411  * arch code will notice on return to user mode, in case those bits
412  * are scarce.  We set TIF_SIGPENDING here to ensure that the arch
413  * signal code always gets run when TIF_RESTORE_SIGMASK is set.
414  */
415 static inline void set_restore_sigmask(void)
416 {
417         set_thread_flag(TIF_RESTORE_SIGMASK);
418         WARN_ON(!test_thread_flag(TIF_SIGPENDING));
419 }
420 static inline void clear_restore_sigmask(void)
421 {
422         clear_thread_flag(TIF_RESTORE_SIGMASK);
423 }
424 static inline bool test_restore_sigmask(void)
425 {
426         return test_thread_flag(TIF_RESTORE_SIGMASK);
427 }
428 static inline bool test_and_clear_restore_sigmask(void)
429 {
430         return test_and_clear_thread_flag(TIF_RESTORE_SIGMASK);
431 }
432 
433 #else   /* TIF_RESTORE_SIGMASK */
434 
435 /* Higher-quality implementation, used if TIF_RESTORE_SIGMASK doesn't exist. */
436 static inline void set_restore_sigmask(void)
437 {
438         current->restore_sigmask = true;
439         WARN_ON(!test_thread_flag(TIF_SIGPENDING));
440 }
441 static inline void clear_restore_sigmask(void)
442 {
443         current->restore_sigmask = false;
444 }
445 static inline bool test_restore_sigmask(void)
446 {
447         return current->restore_sigmask;
448 }
449 static inline bool test_and_clear_restore_sigmask(void)
450 {
451         if (!current->restore_sigmask)
452                 return false;
453         current->restore_sigmask = false;
454         return true;
455 }
456 #endif
457 
458 static inline void restore_saved_sigmask(void)
459 {
460         if (test_and_clear_restore_sigmask())
461                 __set_current_blocked(&current->saved_sigmask);
462 }
463 
464 static inline sigset_t *sigmask_to_save(void)
465 {
466         sigset_t *res = &current->blocked;
467         if (unlikely(test_restore_sigmask()))
468                 res = &current->saved_sigmask;
469         return res;
470 }
471 
472 static inline int kill_cad_pid(int sig, int priv)
473 {
474         return kill_pid(cad_pid, sig, priv);
475 }
476 
477 /* These can be the second arg to send_sig_info/send_group_sig_info.  */
478 #define SEND_SIG_NOINFO ((struct kernel_siginfo *) 0)
479 #define SEND_SIG_PRIV   ((struct kernel_siginfo *) 1)
480 
481 /*
482  * True if we are on the alternate signal stack.
483  */
484 static inline int on_sig_stack(unsigned long sp)
485 {
486         /*
487          * If the signal stack is SS_AUTODISARM then, by construction, we
488          * can't be on the signal stack unless user code deliberately set
489          * SS_AUTODISARM when we were already on it.
490          *
491          * This improves reliability: if user state gets corrupted such that
492          * the stack pointer points very close to the end of the signal stack,
493          * then this check will enable the signal to be handled anyway.
494          */
495         if (current->sas_ss_flags & SS_AUTODISARM)
496                 return 0;
497 
498 #ifdef CONFIG_STACK_GROWSUP
499         return sp >= current->sas_ss_sp &&
500                 sp - current->sas_ss_sp < current->sas_ss_size;
501 #else
502         return sp > current->sas_ss_sp &&
503                 sp - current->sas_ss_sp <= current->sas_ss_size;
504 #endif
505 }
506 
507 static inline int sas_ss_flags(unsigned long sp)
508 {
509         if (!current->sas_ss_size)
510                 return SS_DISABLE;
511 
512         return on_sig_stack(sp) ? SS_ONSTACK : 0;
513 }
514 
515 static inline void sas_ss_reset(struct task_struct *p)
516 {
517         p->sas_ss_sp = 0;
518         p->sas_ss_size = 0;
519         p->sas_ss_flags = SS_DISABLE;
520 }
521 
522 static inline unsigned long sigsp(unsigned long sp, struct ksignal *ksig)
523 {
524         if (unlikely((ksig->ka.sa.sa_flags & SA_ONSTACK)) && ! sas_ss_flags(sp))
525 #ifdef CONFIG_STACK_GROWSUP
526                 return current->sas_ss_sp;
527 #else
528                 return current->sas_ss_sp + current->sas_ss_size;
529 #endif
530         return sp;
531 }
532 
533 extern void __cleanup_sighand(struct sighand_struct *);
534 extern void flush_itimer_signals(void);
535 
536 #define tasklist_empty() \
537         list_empty(&init_task.tasks)
538 
539 #define next_task(p) \
540         list_entry_rcu((p)->tasks.next, struct task_struct, tasks)
541 
542 #define for_each_process(p) \
543         for (p = &init_task ; (p = next_task(p)) != &init_task ; )
544 
545 extern bool current_is_single_threaded(void);
546 
547 /*
548  * Careful: do_each_thread/while_each_thread is a double loop so
549  *          'break' will not work as expected - use goto instead.
550  */
551 #define do_each_thread(g, t) \
552         for (g = t = &init_task ; (g = t = next_task(g)) != &init_task ; ) do
553 
554 #define while_each_thread(g, t) \
555         while ((t = next_thread(t)) != g)
556 
557 #define __for_each_thread(signal, t)    \
558         list_for_each_entry_rcu(t, &(signal)->thread_head, thread_node)
559 
560 #define for_each_thread(p, t)           \
561         __for_each_thread((p)->signal, t)
562 
563 /* Careful: this is a double loop, 'break' won't work as expected. */
564 #define for_each_process_thread(p, t)   \
565         for_each_process(p) for_each_thread(p, t)
566 
567 typedef int (*proc_visitor)(struct task_struct *p, void *data);
568 void walk_process_tree(struct task_struct *top, proc_visitor, void *);
569 
570 static inline
571 struct pid *task_pid_type(struct task_struct *task, enum pid_type type)
572 {
573         struct pid *pid;
574         if (type == PIDTYPE_PID)
575                 pid = task_pid(task);
576         else
577                 pid = task->signal->pids[type];
578         return pid;
579 }
580 
581 static inline struct pid *task_tgid(struct task_struct *task)
582 {
583         return task->signal->pids[PIDTYPE_TGID];
584 }
585 
586 /*
587  * Without tasklist or RCU lock it is not safe to dereference
588  * the result of task_pgrp/task_session even if task == current,
589  * we can race with another thread doing sys_setsid/sys_setpgid.
590  */
591 static inline struct pid *task_pgrp(struct task_struct *task)
592 {
593         return task->signal->pids[PIDTYPE_PGID];
594 }
595 
596 static inline struct pid *task_session(struct task_struct *task)
597 {
598         return task->signal->pids[PIDTYPE_SID];
599 }
600 
601 static inline int get_nr_threads(struct task_struct *tsk)
602 {
603         return tsk->signal->nr_threads;
604 }
605 
606 static inline bool thread_group_leader(struct task_struct *p)
607 {
608         return p->exit_signal >= 0;
609 }
610 
611 /* Do to the insanities of de_thread it is possible for a process
612  * to have the pid of the thread group leader without actually being
613  * the thread group leader.  For iteration through the pids in proc
614  * all we care about is that we have a task with the appropriate
615  * pid, we don't actually care if we have the right task.
616  */
617 static inline bool has_group_leader_pid(struct task_struct *p)
618 {
619         return task_pid(p) == task_tgid(p);
620 }
621 
622 static inline
623 bool same_thread_group(struct task_struct *p1, struct task_struct *p2)
624 {
625         return p1->signal == p2->signal;
626 }
627 
628 static inline struct task_struct *next_thread(const struct task_struct *p)
629 {
630         return list_entry_rcu(p->thread_group.next,
631                               struct task_struct, thread_group);
632 }
633 
634 static inline int thread_group_empty(struct task_struct *p)
635 {
636         return list_empty(&p->thread_group);
637 }
638 
639 #define delay_group_leader(p) \
640                 (thread_group_leader(p) && !thread_group_empty(p))
641 
642 extern struct sighand_struct *__lock_task_sighand(struct task_struct *tsk,
643                                                         unsigned long *flags);
644 
645 static inline struct sighand_struct *lock_task_sighand(struct task_struct *tsk,
646                                                        unsigned long *flags)
647 {
648         struct sighand_struct *ret;
649 
650         ret = __lock_task_sighand(tsk, flags);
651         (void)__cond_lock(&tsk->sighand->siglock, ret);
652         return ret;
653 }
654 
655 static inline void unlock_task_sighand(struct task_struct *tsk,
656                                                 unsigned long *flags)
657 {
658         spin_unlock_irqrestore(&tsk->sighand->siglock, *flags);
659 }
660 
661 static inline unsigned long task_rlimit(const struct task_struct *tsk,
662                 unsigned int limit)
663 {
664         return READ_ONCE(tsk->signal->rlim[limit].rlim_cur);
665 }
666 
667 static inline unsigned long task_rlimit_max(const struct task_struct *tsk,
668                 unsigned int limit)
669 {
670         return READ_ONCE(tsk->signal->rlim[limit].rlim_max);
671 }
672 
673 static inline unsigned long rlimit(unsigned int limit)
674 {
675         return task_rlimit(current, limit);
676 }
677 
678 static inline unsigned long rlimit_max(unsigned int limit)
679 {
680         return task_rlimit_max(current, limit);
681 }
682 
683 #endif /* _LINUX_SCHED_SIGNAL_H */
684 

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