Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * linux/kernel/exit.c |
| 3 | * |
| 4 | * Copyright (C) 1991, 1992 Linus Torvalds |
| 5 | */ |
| 6 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | #include <linux/mm.h> |
| 8 | #include <linux/slab.h> |
| 9 | #include <linux/interrupt.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 10 | #include <linux/module.h> |
Randy.Dunlap | c59ede7 | 2006-01-11 12:17:46 -0800 | [diff] [blame] | 11 | #include <linux/capability.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/completion.h> |
| 13 | #include <linux/personality.h> |
| 14 | #include <linux/tty.h> |
Kirill Korotaev | 6b3286e | 2006-12-08 02:37:56 -0800 | [diff] [blame] | 15 | #include <linux/mnt_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/key.h> |
| 17 | #include <linux/security.h> |
| 18 | #include <linux/cpu.h> |
| 19 | #include <linux/acct.h> |
Jay Lan | 8f0ab51 | 2006-09-30 23:28:59 -0700 | [diff] [blame] | 20 | #include <linux/tsacct_kern.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/file.h> |
| 22 | #include <linux/binfmts.h> |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 23 | #include <linux/nsproxy.h> |
Sukadev Bhattiprolu | 84d7378 | 2006-12-08 02:38:01 -0800 | [diff] [blame] | 24 | #include <linux/pid_namespace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 25 | #include <linux/ptrace.h> |
| 26 | #include <linux/profile.h> |
| 27 | #include <linux/mount.h> |
| 28 | #include <linux/proc_fs.h> |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 29 | #include <linux/kthread.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | #include <linux/mempolicy.h> |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 31 | #include <linux/taskstats_kern.h> |
Shailabh Nagar | ca74e92 | 2006-07-14 00:24:36 -0700 | [diff] [blame] | 32 | #include <linux/delayacct.h> |
Rafael J. Wysocki | 8314418 | 2007-07-17 04:03:35 -0700 | [diff] [blame] | 33 | #include <linux/freezer.h> |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 34 | #include <linux/cgroup.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 35 | #include <linux/syscalls.h> |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 36 | #include <linux/signal.h> |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 37 | #include <linux/posix-timers.h> |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 38 | #include <linux/cn_proc.h> |
Ingo Molnar | de5097c | 2006-01-09 15:59:21 -0800 | [diff] [blame] | 39 | #include <linux/mutex.h> |
Ingo Molnar | 0771dfe | 2006-03-27 01:16:22 -0800 | [diff] [blame] | 40 | #include <linux/futex.h> |
Ingo Molnar | 34f192c | 2006-03-27 01:16:24 -0800 | [diff] [blame] | 41 | #include <linux/compat.h> |
Jens Axboe | b92ce55 | 2006-04-11 13:52:07 +0200 | [diff] [blame] | 42 | #include <linux/pipe_fs_i.h> |
Al Viro | fa84cb9 | 2006-03-29 20:30:19 -0500 | [diff] [blame] | 43 | #include <linux/audit.h> /* for audit_free() */ |
Adrian Bunk | 83cc5ed | 2006-06-25 05:47:41 -0700 | [diff] [blame] | 44 | #include <linux/resource.h> |
David Howells | 0d67a46 | 2006-08-29 19:05:56 +0100 | [diff] [blame] | 45 | #include <linux/blkdev.h> |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 46 | #include <linux/task_io_accounting_ops.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | |
| 48 | #include <asm/uaccess.h> |
| 49 | #include <asm/unistd.h> |
| 50 | #include <asm/pgtable.h> |
| 51 | #include <asm/mmu_context.h> |
| 52 | |
Adrian Bunk | 408b664 | 2005-05-01 08:59:29 -0700 | [diff] [blame] | 53 | static void exit_mm(struct task_struct * tsk); |
| 54 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | static void __unhash_process(struct task_struct *p) |
| 56 | { |
| 57 | nr_threads--; |
| 58 | detach_pid(p, PIDTYPE_PID); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 59 | if (thread_group_leader(p)) { |
| 60 | detach_pid(p, PIDTYPE_PGID); |
| 61 | detach_pid(p, PIDTYPE_SID); |
Oleg Nesterov | c97d989 | 2006-03-28 16:11:06 -0800 | [diff] [blame] | 62 | |
Eric W. Biederman | 5e85d4a | 2006-04-18 22:20:16 -0700 | [diff] [blame] | 63 | list_del_rcu(&p->tasks); |
Oleg Nesterov | 73b9ebf | 2006-03-28 16:11:07 -0800 | [diff] [blame] | 64 | __get_cpu_var(process_counts)--; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 65 | } |
Oleg Nesterov | 47e6532 | 2006-03-28 16:11:25 -0800 | [diff] [blame] | 66 | list_del_rcu(&p->thread_group); |
Oleg Nesterov | c97d989 | 2006-03-28 16:11:06 -0800 | [diff] [blame] | 67 | remove_parent(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | } |
| 69 | |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 70 | /* |
| 71 | * This function expects the tasklist_lock write-locked. |
| 72 | */ |
| 73 | static void __exit_signal(struct task_struct *tsk) |
| 74 | { |
| 75 | struct signal_struct *sig = tsk->signal; |
| 76 | struct sighand_struct *sighand; |
| 77 | |
| 78 | BUG_ON(!sig); |
| 79 | BUG_ON(!atomic_read(&sig->count)); |
| 80 | |
| 81 | rcu_read_lock(); |
| 82 | sighand = rcu_dereference(tsk->sighand); |
| 83 | spin_lock(&sighand->siglock); |
| 84 | |
| 85 | posix_cpu_timers_exit(tsk); |
| 86 | if (atomic_dec_and_test(&sig->count)) |
| 87 | posix_cpu_timers_exit_group(tsk); |
| 88 | else { |
| 89 | /* |
| 90 | * If there is any task waiting for the group exit |
| 91 | * then notify it: |
| 92 | */ |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 93 | if (sig->group_exit_task && atomic_read(&sig->count) == sig->notify_count) |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 94 | wake_up_process(sig->group_exit_task); |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 95 | |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 96 | if (tsk == sig->curr_target) |
| 97 | sig->curr_target = next_thread(tsk); |
| 98 | /* |
| 99 | * Accumulate here the counters for all threads but the |
| 100 | * group leader as they die, so they can be added into |
| 101 | * the process-wide totals when those are taken. |
| 102 | * The group leader stays around as a zombie as long |
| 103 | * as there are other threads. When it gets reaped, |
| 104 | * the exit.c code will add its counts into these totals. |
| 105 | * We won't ever get here for the group leader, since it |
| 106 | * will have been the last reference on the signal_struct. |
| 107 | */ |
| 108 | sig->utime = cputime_add(sig->utime, tsk->utime); |
| 109 | sig->stime = cputime_add(sig->stime, tsk->stime); |
Laurent Vivier | 9ac5231 | 2007-10-15 17:00:19 +0200 | [diff] [blame] | 110 | sig->gtime = cputime_add(sig->gtime, tsk->gtime); |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 111 | sig->min_flt += tsk->min_flt; |
| 112 | sig->maj_flt += tsk->maj_flt; |
| 113 | sig->nvcsw += tsk->nvcsw; |
| 114 | sig->nivcsw += tsk->nivcsw; |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 115 | sig->inblock += task_io_get_inblock(tsk); |
| 116 | sig->oublock += task_io_get_oublock(tsk); |
Balbir Singh | 172ba84 | 2007-07-09 18:52:00 +0200 | [diff] [blame] | 117 | sig->sum_sched_runtime += tsk->se.sum_exec_runtime; |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 118 | sig = NULL; /* Marker for below. */ |
| 119 | } |
| 120 | |
Oleg Nesterov | 5876700 | 2006-03-28 16:11:20 -0800 | [diff] [blame] | 121 | __unhash_process(tsk); |
| 122 | |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 123 | tsk->signal = NULL; |
Oleg Nesterov | a7e5328 | 2006-03-28 16:11:27 -0800 | [diff] [blame] | 124 | tsk->sighand = NULL; |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 125 | spin_unlock(&sighand->siglock); |
| 126 | rcu_read_unlock(); |
| 127 | |
Oleg Nesterov | a7e5328 | 2006-03-28 16:11:27 -0800 | [diff] [blame] | 128 | __cleanup_sighand(sighand); |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 129 | clear_tsk_thread_flag(tsk,TIF_SIGPENDING); |
| 130 | flush_sigqueue(&tsk->pending); |
| 131 | if (sig) { |
| 132 | flush_sigqueue(&sig->shared_pending); |
Oleg Nesterov | 093a8e8 | 2006-10-28 10:38:51 -0700 | [diff] [blame] | 133 | taskstats_tgid_free(sig); |
Oleg Nesterov | 6a14c5c | 2006-03-28 16:11:18 -0800 | [diff] [blame] | 134 | __cleanup_signal(sig); |
| 135 | } |
| 136 | } |
| 137 | |
Eric W. Biederman | 8c7904a | 2006-03-31 02:31:37 -0800 | [diff] [blame] | 138 | static void delayed_put_task_struct(struct rcu_head *rhp) |
| 139 | { |
| 140 | put_task_struct(container_of(rhp, struct task_struct, rcu)); |
| 141 | } |
| 142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 143 | void release_task(struct task_struct * p) |
| 144 | { |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 145 | struct task_struct *leader; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 146 | int zap_leader; |
Oleg Nesterov | 1f09f97 | 2006-03-28 16:11:11 -0800 | [diff] [blame] | 147 | repeat: |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | atomic_dec(&p->user->processes); |
Pavel Emelyanov | 60347f6 | 2007-10-18 23:40:03 -0700 | [diff] [blame] | 149 | proc_flush_task(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 150 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | 1f09f97 | 2006-03-28 16:11:11 -0800 | [diff] [blame] | 151 | ptrace_unlink(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 152 | BUG_ON(!list_empty(&p->ptrace_list) || !list_empty(&p->ptrace_children)); |
| 153 | __exit_signal(p); |
Oleg Nesterov | 35f5cad | 2006-03-28 16:11:19 -0800 | [diff] [blame] | 154 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | /* |
| 156 | * If we are the last non-leader member of the thread |
| 157 | * group, and the leader is zombie, then notify the |
| 158 | * group leader's parent process. (if it wants notification.) |
| 159 | */ |
| 160 | zap_leader = 0; |
| 161 | leader = p->group_leader; |
| 162 | if (leader != p && thread_group_empty(leader) && leader->exit_state == EXIT_ZOMBIE) { |
| 163 | BUG_ON(leader->exit_signal == -1); |
| 164 | do_notify_parent(leader, leader->exit_signal); |
| 165 | /* |
| 166 | * If we were the last child thread and the leader has |
| 167 | * exited already, and the leader's parent ignores SIGCHLD, |
| 168 | * then we are the one who should release the leader. |
| 169 | * |
| 170 | * do_notify_parent() will have marked it self-reaping in |
| 171 | * that case. |
| 172 | */ |
| 173 | zap_leader = (leader->exit_signal == -1); |
| 174 | } |
| 175 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 176 | write_unlock_irq(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 177 | release_thread(p); |
Eric W. Biederman | 8c7904a | 2006-03-31 02:31:37 -0800 | [diff] [blame] | 178 | call_rcu(&p->rcu, delayed_put_task_struct); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 179 | |
| 180 | p = leader; |
| 181 | if (unlikely(zap_leader)) |
| 182 | goto repeat; |
| 183 | } |
| 184 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 185 | /* |
| 186 | * This checks not only the pgrp, but falls back on the pid if no |
| 187 | * satisfactory pgrp is found. I dunno - gdb doesn't work correctly |
| 188 | * without this... |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 189 | * |
| 190 | * The caller must hold rcu lock or the tasklist lock. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 191 | */ |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 192 | struct pid *session_of_pgrp(struct pid *pgrp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 193 | { |
| 194 | struct task_struct *p; |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 195 | struct pid *sid = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 197 | p = pid_task(pgrp, PIDTYPE_PGID); |
Oleg Nesterov | 62dfb55 | 2006-12-08 02:38:03 -0800 | [diff] [blame] | 198 | if (p == NULL) |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 199 | p = pid_task(pgrp, PIDTYPE_PID); |
Oleg Nesterov | 62dfb55 | 2006-12-08 02:38:03 -0800 | [diff] [blame] | 200 | if (p != NULL) |
Eric W. Biederman | 04a2e6a | 2007-02-12 00:52:56 -0800 | [diff] [blame] | 201 | sid = task_session(p); |
Oleg Nesterov | 62dfb55 | 2006-12-08 02:38:03 -0800 | [diff] [blame] | 202 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 203 | return sid; |
| 204 | } |
| 205 | |
| 206 | /* |
| 207 | * Determine if a process group is "orphaned", according to the POSIX |
| 208 | * definition in 2.2.2.52. Orphaned process groups are not to be affected |
| 209 | * by terminal-generated stop signals. Newly orphaned process groups are |
| 210 | * to receive a SIGHUP and a SIGCONT. |
| 211 | * |
| 212 | * "I ask you, have you ever known what it is to be an orphan?" |
| 213 | */ |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 214 | static int will_become_orphaned_pgrp(struct pid *pgrp, struct task_struct *ignored_task) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | { |
| 216 | struct task_struct *p; |
| 217 | int ret = 1; |
| 218 | |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 219 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 220 | if (p == ignored_task |
| 221 | || p->exit_state |
Serge E. Hallyn | b460cbc | 2007-10-18 23:39:52 -0700 | [diff] [blame] | 222 | || is_global_init(p->real_parent)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 223 | continue; |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 224 | if (task_pgrp(p->real_parent) != pgrp && |
| 225 | task_session(p->real_parent) == task_session(p)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 226 | ret = 0; |
| 227 | break; |
| 228 | } |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 229 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | return ret; /* (sighing) "Often!" */ |
| 231 | } |
| 232 | |
Eric W. Biederman | 3e7cd6c | 2007-02-12 00:52:58 -0800 | [diff] [blame] | 233 | int is_current_pgrp_orphaned(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 234 | { |
| 235 | int retval; |
| 236 | |
| 237 | read_lock(&tasklist_lock); |
Eric W. Biederman | 3e7cd6c | 2007-02-12 00:52:58 -0800 | [diff] [blame] | 238 | retval = will_become_orphaned_pgrp(task_pgrp(current), NULL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | read_unlock(&tasklist_lock); |
| 240 | |
| 241 | return retval; |
| 242 | } |
| 243 | |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 244 | static int has_stopped_jobs(struct pid *pgrp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 245 | { |
| 246 | int retval = 0; |
| 247 | struct task_struct *p; |
| 248 | |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 249 | do_each_pid_task(pgrp, PIDTYPE_PGID, p) { |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 250 | if (!task_is_stopped(p)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 251 | continue; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 252 | retval = 1; |
| 253 | break; |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 254 | } while_each_pid_task(pgrp, PIDTYPE_PGID, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 255 | return retval; |
| 256 | } |
| 257 | |
| 258 | /** |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 259 | * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 260 | * |
| 261 | * If a kernel thread is launched as a result of a system call, or if |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 262 | * it ever exits, it should generally reparent itself to kthreadd so it |
| 263 | * isn't in the way of other processes and is correctly cleaned up on exit. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 264 | * |
| 265 | * The various task state such as scheduling policy and priority may have |
| 266 | * been inherited from a user process, so we reset them to sane values here. |
| 267 | * |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 268 | * NOTE that reparent_to_kthreadd() gives the caller full capabilities. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 269 | */ |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 270 | static void reparent_to_kthreadd(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | { |
| 272 | write_lock_irq(&tasklist_lock); |
| 273 | |
| 274 | ptrace_unlink(current); |
| 275 | /* Reparent to init */ |
Oleg Nesterov | 9b678ec | 2006-03-28 16:11:05 -0800 | [diff] [blame] | 276 | remove_parent(current); |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 277 | current->real_parent = current->parent = kthreadd_task; |
Oleg Nesterov | 9b678ec | 2006-03-28 16:11:05 -0800 | [diff] [blame] | 278 | add_parent(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | |
| 280 | /* Set the exit signal to SIGCHLD so we signal init on exit */ |
| 281 | current->exit_signal = SIGCHLD; |
| 282 | |
Ingo Molnar | e05606d | 2007-07-09 18:51:59 +0200 | [diff] [blame] | 283 | if (task_nice(current) < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 284 | set_user_nice(current, 0); |
| 285 | /* cpus_allowed? */ |
| 286 | /* rt_priority? */ |
| 287 | /* signals? */ |
| 288 | security_task_reparent_to_init(current); |
| 289 | memcpy(current->signal->rlim, init_task.signal->rlim, |
| 290 | sizeof(current->signal->rlim)); |
| 291 | atomic_inc(&(INIT_USER->__count)); |
| 292 | write_unlock_irq(&tasklist_lock); |
| 293 | switch_uid(INIT_USER); |
| 294 | } |
| 295 | |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 296 | void __set_special_pids(struct pid *pid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | { |
Oren Laadan | e19f247 | 2006-01-08 01:03:58 -0800 | [diff] [blame] | 298 | struct task_struct *curr = current->group_leader; |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 299 | pid_t nr = pid_nr(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 300 | |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 301 | if (task_session(curr) != pid) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | detach_pid(curr, PIDTYPE_SID); |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 303 | attach_pid(curr, PIDTYPE_SID, pid); |
| 304 | set_task_session(curr, nr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | } |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 306 | if (task_pgrp(curr) != pid) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | detach_pid(curr, PIDTYPE_PGID); |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 308 | attach_pid(curr, PIDTYPE_PGID, pid); |
| 309 | set_task_pgrp(curr, nr); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 310 | } |
| 311 | } |
| 312 | |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 313 | static void set_special_pids(struct pid *pid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 314 | { |
| 315 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 316 | __set_special_pids(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 317 | write_unlock_irq(&tasklist_lock); |
| 318 | } |
| 319 | |
| 320 | /* |
| 321 | * Let kernel threads use this to say that they |
| 322 | * allow a certain signal (since daemonize() will |
| 323 | * have disabled all of them by default). |
| 324 | */ |
| 325 | int allow_signal(int sig) |
| 326 | { |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 327 | if (!valid_signal(sig) || sig < 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | return -EINVAL; |
| 329 | |
| 330 | spin_lock_irq(¤t->sighand->siglock); |
| 331 | sigdelset(¤t->blocked, sig); |
| 332 | if (!current->mm) { |
| 333 | /* Kernel threads handle their own signals. |
| 334 | Let the signal code know it'll be handled, so |
| 335 | that they don't get converted to SIGKILL or |
| 336 | just silently dropped */ |
| 337 | current->sighand->action[(sig)-1].sa.sa_handler = (void __user *)2; |
| 338 | } |
| 339 | recalc_sigpending(); |
| 340 | spin_unlock_irq(¤t->sighand->siglock); |
| 341 | return 0; |
| 342 | } |
| 343 | |
| 344 | EXPORT_SYMBOL(allow_signal); |
| 345 | |
| 346 | int disallow_signal(int sig) |
| 347 | { |
Jesper Juhl | 7ed20e1 | 2005-05-01 08:59:14 -0700 | [diff] [blame] | 348 | if (!valid_signal(sig) || sig < 1) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 349 | return -EINVAL; |
| 350 | |
| 351 | spin_lock_irq(¤t->sighand->siglock); |
Oleg Nesterov | 10ab825 | 2007-05-09 02:34:37 -0700 | [diff] [blame] | 352 | current->sighand->action[(sig)-1].sa.sa_handler = SIG_IGN; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 353 | recalc_sigpending(); |
| 354 | spin_unlock_irq(¤t->sighand->siglock); |
| 355 | return 0; |
| 356 | } |
| 357 | |
| 358 | EXPORT_SYMBOL(disallow_signal); |
| 359 | |
| 360 | /* |
| 361 | * Put all the gunge required to become a kernel thread without |
| 362 | * attached user resources in one place where it belongs. |
| 363 | */ |
| 364 | |
| 365 | void daemonize(const char *name, ...) |
| 366 | { |
| 367 | va_list args; |
| 368 | struct fs_struct *fs; |
| 369 | sigset_t blocked; |
| 370 | |
| 371 | va_start(args, name); |
| 372 | vsnprintf(current->comm, sizeof(current->comm), name, args); |
| 373 | va_end(args); |
| 374 | |
| 375 | /* |
| 376 | * If we were started as result of loading a module, close all of the |
| 377 | * user space pages. We don't need them, and if we didn't close them |
| 378 | * they would be locked into memory. |
| 379 | */ |
| 380 | exit_mm(current); |
Rafael J. Wysocki | 8314418 | 2007-07-17 04:03:35 -0700 | [diff] [blame] | 381 | /* |
| 382 | * We don't want to have TIF_FREEZE set if the system-wide hibernation |
| 383 | * or suspend transition begins right now. |
| 384 | */ |
| 385 | current->flags |= PF_NOFREEZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 386 | |
Oleg Nesterov | 8520d7c | 2008-02-08 04:19:09 -0800 | [diff] [blame] | 387 | if (current->nsproxy != &init_nsproxy) { |
| 388 | get_nsproxy(&init_nsproxy); |
| 389 | switch_task_namespaces(current, &init_nsproxy); |
| 390 | } |
Oleg Nesterov | 297bd42 | 2008-02-08 04:19:10 -0800 | [diff] [blame] | 391 | set_special_pids(&init_struct_pid); |
Peter Zijlstra | 24ec839 | 2006-12-08 02:36:04 -0800 | [diff] [blame] | 392 | proc_clear_tty(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 393 | |
| 394 | /* Block and flush all signals */ |
| 395 | sigfillset(&blocked); |
| 396 | sigprocmask(SIG_BLOCK, &blocked, NULL); |
| 397 | flush_signals(current); |
| 398 | |
| 399 | /* Become as one with the init task */ |
| 400 | |
| 401 | exit_fs(current); /* current->fs->count--; */ |
| 402 | fs = init_task.fs; |
| 403 | current->fs = fs; |
| 404 | atomic_inc(&fs->count); |
Serge E. Hallyn | ab51601 | 2006-10-02 02:18:06 -0700 | [diff] [blame] | 405 | |
Daniel Walker | d4c5e41 | 2007-10-18 23:39:59 -0700 | [diff] [blame] | 406 | exit_files(current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 407 | current->files = init_task.files; |
| 408 | atomic_inc(¤t->files->count); |
| 409 | |
Eric W. Biederman | 49d769d | 2007-05-09 02:34:33 -0700 | [diff] [blame] | 410 | reparent_to_kthreadd(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | } |
| 412 | |
| 413 | EXPORT_SYMBOL(daemonize); |
| 414 | |
Arjan van de Ven | 858119e | 2006-01-14 13:20:43 -0800 | [diff] [blame] | 415 | static void close_files(struct files_struct * files) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 416 | { |
| 417 | int i, j; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 418 | struct fdtable *fdt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 419 | |
| 420 | j = 0; |
Dipankar Sarma | 4fb3a53 | 2005-09-16 19:28:13 -0700 | [diff] [blame] | 421 | |
| 422 | /* |
| 423 | * It is safe to dereference the fd table without RCU or |
| 424 | * ->file_lock because this is the last reference to the |
| 425 | * files structure. |
| 426 | */ |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 427 | fdt = files_fdtable(files); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 428 | for (;;) { |
| 429 | unsigned long set; |
| 430 | i = j * __NFDBITS; |
Vadim Lobanov | bbea9f6 | 2006-12-10 02:21:12 -0800 | [diff] [blame] | 431 | if (i >= fdt->max_fds) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | break; |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 433 | set = fdt->open_fds->fds_bits[j++]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 434 | while (set) { |
| 435 | if (set & 1) { |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 436 | struct file * file = xchg(&fdt->fd[i], NULL); |
Ingo Molnar | 944be0b | 2007-02-12 00:52:26 -0800 | [diff] [blame] | 437 | if (file) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | filp_close(file, files); |
Ingo Molnar | 944be0b | 2007-02-12 00:52:26 -0800 | [diff] [blame] | 439 | cond_resched(); |
| 440 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 441 | } |
| 442 | i++; |
| 443 | set >>= 1; |
| 444 | } |
| 445 | } |
| 446 | } |
| 447 | |
| 448 | struct files_struct *get_files_struct(struct task_struct *task) |
| 449 | { |
| 450 | struct files_struct *files; |
| 451 | |
| 452 | task_lock(task); |
| 453 | files = task->files; |
| 454 | if (files) |
| 455 | atomic_inc(&files->count); |
| 456 | task_unlock(task); |
| 457 | |
| 458 | return files; |
| 459 | } |
| 460 | |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 461 | void put_files_struct(struct files_struct *files) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | { |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 463 | struct fdtable *fdt; |
| 464 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 465 | if (atomic_dec_and_test(&files->count)) { |
| 466 | close_files(files); |
| 467 | /* |
| 468 | * Free the fd and fdset arrays if we expanded them. |
Dipankar Sarma | ab2af1f | 2005-09-09 13:04:13 -0700 | [diff] [blame] | 469 | * If the fdtable was embedded, pass files for freeing |
| 470 | * at the end of the RCU grace period. Otherwise, |
| 471 | * you can free files immediately. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 472 | */ |
Dipankar Sarma | badf166 | 2005-09-09 13:04:10 -0700 | [diff] [blame] | 473 | fdt = files_fdtable(files); |
Vadim Lobanov | 4fd4581 | 2006-12-10 02:21:17 -0800 | [diff] [blame] | 474 | if (fdt != &files->fdtab) |
Dipankar Sarma | ab2af1f | 2005-09-09 13:04:13 -0700 | [diff] [blame] | 475 | kmem_cache_free(files_cachep, files); |
Vadim Lobanov | 01b2d93 | 2006-12-22 01:10:43 -0800 | [diff] [blame] | 476 | free_fdtable(fdt); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 477 | } |
| 478 | } |
| 479 | |
| 480 | EXPORT_SYMBOL(put_files_struct); |
| 481 | |
Kirill Korotaev | 3b9b8ab | 2006-09-29 02:00:05 -0700 | [diff] [blame] | 482 | void reset_files_struct(struct task_struct *tsk, struct files_struct *files) |
| 483 | { |
| 484 | struct files_struct *old; |
| 485 | |
| 486 | old = tsk->files; |
| 487 | task_lock(tsk); |
| 488 | tsk->files = files; |
| 489 | task_unlock(tsk); |
| 490 | put_files_struct(old); |
| 491 | } |
| 492 | EXPORT_SYMBOL(reset_files_struct); |
| 493 | |
Alexey Dobriyan | a39bc51 | 2007-10-18 23:41:10 -0700 | [diff] [blame] | 494 | static void __exit_files(struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 495 | { |
| 496 | struct files_struct * files = tsk->files; |
| 497 | |
| 498 | if (files) { |
| 499 | task_lock(tsk); |
| 500 | tsk->files = NULL; |
| 501 | task_unlock(tsk); |
| 502 | put_files_struct(files); |
| 503 | } |
| 504 | } |
| 505 | |
| 506 | void exit_files(struct task_struct *tsk) |
| 507 | { |
| 508 | __exit_files(tsk); |
| 509 | } |
| 510 | |
Alexey Dobriyan | a39bc51 | 2007-10-18 23:41:10 -0700 | [diff] [blame] | 511 | static void __put_fs_struct(struct fs_struct *fs) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 512 | { |
| 513 | /* No need to hold fs->lock if we are killing it */ |
| 514 | if (atomic_dec_and_test(&fs->count)) { |
Jan Blunck | 6ac08c3 | 2008-02-14 19:34:38 -0800 | [diff] [blame] | 515 | path_put(&fs->root); |
| 516 | path_put(&fs->pwd); |
| 517 | if (fs->altroot.dentry) |
| 518 | path_put(&fs->altroot); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 519 | kmem_cache_free(fs_cachep, fs); |
| 520 | } |
| 521 | } |
| 522 | |
| 523 | void put_fs_struct(struct fs_struct *fs) |
| 524 | { |
| 525 | __put_fs_struct(fs); |
| 526 | } |
| 527 | |
Alexey Dobriyan | a39bc51 | 2007-10-18 23:41:10 -0700 | [diff] [blame] | 528 | static void __exit_fs(struct task_struct *tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 529 | { |
| 530 | struct fs_struct * fs = tsk->fs; |
| 531 | |
| 532 | if (fs) { |
| 533 | task_lock(tsk); |
| 534 | tsk->fs = NULL; |
| 535 | task_unlock(tsk); |
| 536 | __put_fs_struct(fs); |
| 537 | } |
| 538 | } |
| 539 | |
| 540 | void exit_fs(struct task_struct *tsk) |
| 541 | { |
| 542 | __exit_fs(tsk); |
| 543 | } |
| 544 | |
| 545 | EXPORT_SYMBOL_GPL(exit_fs); |
| 546 | |
| 547 | /* |
| 548 | * Turn us into a lazy TLB process if we |
| 549 | * aren't already.. |
| 550 | */ |
Adrian Bunk | 408b664 | 2005-05-01 08:59:29 -0700 | [diff] [blame] | 551 | static void exit_mm(struct task_struct * tsk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 552 | { |
| 553 | struct mm_struct *mm = tsk->mm; |
| 554 | |
| 555 | mm_release(tsk, mm); |
| 556 | if (!mm) |
| 557 | return; |
| 558 | /* |
| 559 | * Serialize with any possible pending coredump. |
| 560 | * We must hold mmap_sem around checking core_waiters |
| 561 | * and clearing tsk->mm. The core-inducing thread |
| 562 | * will increment core_waiters for each thread in the |
| 563 | * group with ->mm != NULL. |
| 564 | */ |
| 565 | down_read(&mm->mmap_sem); |
| 566 | if (mm->core_waiters) { |
| 567 | up_read(&mm->mmap_sem); |
| 568 | down_write(&mm->mmap_sem); |
| 569 | if (!--mm->core_waiters) |
| 570 | complete(mm->core_startup_done); |
| 571 | up_write(&mm->mmap_sem); |
| 572 | |
| 573 | wait_for_completion(&mm->core_done); |
| 574 | down_read(&mm->mmap_sem); |
| 575 | } |
| 576 | atomic_inc(&mm->mm_count); |
Eric Sesterhenn | 125e187 | 2006-06-23 02:06:06 -0700 | [diff] [blame] | 577 | BUG_ON(mm != tsk->active_mm); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 578 | /* more a memory barrier than a real lock */ |
| 579 | task_lock(tsk); |
| 580 | tsk->mm = NULL; |
| 581 | up_read(&mm->mmap_sem); |
| 582 | enter_lazy_tlb(mm, current); |
Rafael J. Wysocki | 0c1eecf | 2007-07-19 01:47:33 -0700 | [diff] [blame] | 583 | /* We don't want this task to be frozen prematurely */ |
| 584 | clear_freeze_flag(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 585 | task_unlock(tsk); |
| 586 | mmput(mm); |
| 587 | } |
| 588 | |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 589 | static void |
| 590 | reparent_thread(struct task_struct *p, struct task_struct *father, int traced) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 591 | { |
Oleg Nesterov | 241ceee | 2006-12-24 23:30:44 +0300 | [diff] [blame] | 592 | if (p->pdeath_signal) |
| 593 | /* We already hold the tasklist_lock here. */ |
| 594 | group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p); |
| 595 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 596 | /* Move the child from its dying parent to the new one. */ |
| 597 | if (unlikely(traced)) { |
| 598 | /* Preserve ptrace links if someone else is tracing this child. */ |
| 599 | list_del_init(&p->ptrace_list); |
| 600 | if (p->parent != p->real_parent) |
| 601 | list_add(&p->ptrace_list, &p->real_parent->ptrace_children); |
| 602 | } else { |
| 603 | /* If this child is being traced, then we're the one tracing it |
| 604 | * anyway, so let go of it. |
| 605 | */ |
| 606 | p->ptrace = 0; |
Oleg Nesterov | 6ac781b | 2006-03-28 16:11:09 -0800 | [diff] [blame] | 607 | remove_parent(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 608 | p->parent = p->real_parent; |
Oleg Nesterov | 6ac781b | 2006-03-28 16:11:09 -0800 | [diff] [blame] | 609 | add_parent(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 610 | |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 611 | if (task_is_traced(p)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 612 | /* |
| 613 | * If it was at a trace stop, turn it into |
| 614 | * a normal stop since it's no longer being |
| 615 | * traced. |
| 616 | */ |
| 617 | ptrace_untrace(p); |
| 618 | } |
| 619 | } |
| 620 | |
Eric W. Biederman | b2b2cbc | 2006-12-21 21:28:40 -0700 | [diff] [blame] | 621 | /* If this is a threaded reparent there is no need to |
| 622 | * notify anyone anything has happened. |
| 623 | */ |
| 624 | if (p->real_parent->group_leader == father->group_leader) |
| 625 | return; |
| 626 | |
| 627 | /* We don't want people slaying init. */ |
| 628 | if (p->exit_signal != -1) |
| 629 | p->exit_signal = SIGCHLD; |
Eric W. Biederman | b2b2cbc | 2006-12-21 21:28:40 -0700 | [diff] [blame] | 630 | |
| 631 | /* If we'd notified the old parent about this child's death, |
| 632 | * also notify the new parent. |
| 633 | */ |
| 634 | if (!traced && p->exit_state == EXIT_ZOMBIE && |
| 635 | p->exit_signal != -1 && thread_group_empty(p)) |
| 636 | do_notify_parent(p, p->exit_signal); |
| 637 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 638 | /* |
| 639 | * process group orphan check |
| 640 | * Case ii: Our child is in a different pgrp |
| 641 | * than we are, and it was the only connection |
| 642 | * outside, so the child pgrp is now orphaned. |
| 643 | */ |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 644 | if ((task_pgrp(p) != task_pgrp(father)) && |
| 645 | (task_session(p) == task_session(father))) { |
| 646 | struct pid *pgrp = task_pgrp(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 647 | |
Cedric Le Goater | 937949d | 2006-12-08 02:37:54 -0800 | [diff] [blame] | 648 | if (will_become_orphaned_pgrp(pgrp, NULL) && |
| 649 | has_stopped_jobs(pgrp)) { |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 650 | __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp); |
| 651 | __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 652 | } |
| 653 | } |
| 654 | } |
| 655 | |
| 656 | /* |
| 657 | * When we die, we re-parent all our children. |
| 658 | * Try to give them to another thread in our thread |
| 659 | * group, and if no such member exists, give it to |
Sukadev Bhattiprolu | 84d7378 | 2006-12-08 02:38:01 -0800 | [diff] [blame] | 660 | * the child reaper process (ie "init") in our pid |
| 661 | * space. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | */ |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 663 | static void forget_original_parent(struct task_struct *father) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | { |
Matthias Kaehlcke | 03ff179 | 2007-10-18 23:39:57 -0700 | [diff] [blame] | 665 | struct task_struct *p, *n, *reaper = father; |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 666 | struct list_head ptrace_dead; |
| 667 | |
| 668 | INIT_LIST_HEAD(&ptrace_dead); |
| 669 | |
| 670 | write_lock_irq(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 671 | |
| 672 | do { |
| 673 | reaper = next_thread(reaper); |
| 674 | if (reaper == father) { |
Sukadev Bhattiprolu | 88f21d8 | 2007-10-18 23:39:50 -0700 | [diff] [blame] | 675 | reaper = task_child_reaper(father); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 676 | break; |
| 677 | } |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 678 | } while (reaper->flags & PF_EXITING); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 679 | |
| 680 | /* |
| 681 | * There are only two places where our children can be: |
| 682 | * |
| 683 | * - in our child list |
| 684 | * - in our ptraced child list |
| 685 | * |
| 686 | * Search them and reparent children. |
| 687 | */ |
Matthias Kaehlcke | 03ff179 | 2007-10-18 23:39:57 -0700 | [diff] [blame] | 688 | list_for_each_entry_safe(p, n, &father->children, sibling) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 689 | int ptrace; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 690 | |
| 691 | ptrace = p->ptrace; |
| 692 | |
| 693 | /* if father isn't the real parent, then ptrace must be enabled */ |
| 694 | BUG_ON(father != p->real_parent && !ptrace); |
| 695 | |
| 696 | if (father == p->real_parent) { |
| 697 | /* reparent with a reaper, real father it's us */ |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 698 | p->real_parent = reaper; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 699 | reparent_thread(p, father, 0); |
| 700 | } else { |
| 701 | /* reparent ptraced task to its real parent */ |
| 702 | __ptrace_unlink (p); |
| 703 | if (p->exit_state == EXIT_ZOMBIE && p->exit_signal != -1 && |
| 704 | thread_group_empty(p)) |
| 705 | do_notify_parent(p, p->exit_signal); |
| 706 | } |
| 707 | |
| 708 | /* |
| 709 | * if the ptraced child is a zombie with exit_signal == -1 |
| 710 | * we must collect it before we exit, or it will remain |
| 711 | * zombie forever since we prevented it from self-reap itself |
| 712 | * while it was being traced by us, to be able to see it in wait4. |
| 713 | */ |
| 714 | if (unlikely(ptrace && p->exit_state == EXIT_ZOMBIE && p->exit_signal == -1)) |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 715 | list_add(&p->ptrace_list, &ptrace_dead); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 716 | } |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 717 | |
Matthias Kaehlcke | 03ff179 | 2007-10-18 23:39:57 -0700 | [diff] [blame] | 718 | list_for_each_entry_safe(p, n, &father->ptrace_children, ptrace_list) { |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 719 | p->real_parent = reaper; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | reparent_thread(p, father, 1); |
| 721 | } |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 722 | |
| 723 | write_unlock_irq(&tasklist_lock); |
| 724 | BUG_ON(!list_empty(&father->children)); |
| 725 | BUG_ON(!list_empty(&father->ptrace_children)); |
| 726 | |
| 727 | list_for_each_entry_safe(p, n, &ptrace_dead, ptrace_list) { |
| 728 | list_del_init(&p->ptrace_list); |
| 729 | release_task(p); |
| 730 | } |
| 731 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 732 | } |
| 733 | |
| 734 | /* |
| 735 | * Send signals to all our closest relatives so that they know |
| 736 | * to properly mourn us.. |
| 737 | */ |
| 738 | static void exit_notify(struct task_struct *tsk) |
| 739 | { |
| 740 | int state; |
| 741 | struct task_struct *t; |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 742 | struct pid *pgrp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 743 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | /* |
| 745 | * This does two things: |
| 746 | * |
| 747 | * A. Make init inherit all the child processes |
| 748 | * B. Check to see if any process groups have become orphaned |
| 749 | * as a result of our exiting, and if they have any stopped |
| 750 | * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) |
| 751 | */ |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 752 | forget_original_parent(tsk); |
Pavel Emelyanov | 2e4a707 | 2007-10-18 23:40:01 -0700 | [diff] [blame] | 753 | exit_task_namespaces(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 754 | |
Oleg Nesterov | 762a24b | 2007-10-18 23:40:00 -0700 | [diff] [blame] | 755 | write_lock_irq(&tasklist_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 756 | /* |
| 757 | * Check to see if any process groups have become orphaned |
| 758 | * as a result of our exiting, and if they have any stopped |
| 759 | * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) |
| 760 | * |
| 761 | * Case i: Our father is in a different pgrp than we are |
| 762 | * and we were the only connection outside, so our pgrp |
| 763 | * is about to become orphaned. |
| 764 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 765 | t = tsk->real_parent; |
Oleg Nesterov | 3ae4cba | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 766 | |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 767 | pgrp = task_pgrp(tsk); |
| 768 | if ((task_pgrp(t) != pgrp) && |
Eric W. Biederman | 14e9d57 | 2007-03-28 23:38:16 -0600 | [diff] [blame] | 769 | (task_session(t) == task_session(tsk)) && |
Eric W. Biederman | 0475ac0 | 2007-02-12 00:52:57 -0800 | [diff] [blame] | 770 | will_become_orphaned_pgrp(pgrp, tsk) && |
| 771 | has_stopped_jobs(pgrp)) { |
| 772 | __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp); |
| 773 | __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 774 | } |
| 775 | |
Oleg Nesterov | 2472844 | 2007-08-04 01:04:41 +0400 | [diff] [blame] | 776 | /* Let father know we died |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 777 | * |
| 778 | * Thread signals are configurable, but you aren't going to use |
Daniel Walker | d4c5e41 | 2007-10-18 23:39:59 -0700 | [diff] [blame] | 779 | * that to send signals to arbitary processes. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 780 | * That stops right now. |
| 781 | * |
| 782 | * If the parent exec id doesn't match the exec id we saved |
| 783 | * when we started then we know the parent has changed security |
| 784 | * domain. |
| 785 | * |
| 786 | * If our self_exec id doesn't match our parent_exec_id then |
| 787 | * we have changed execution domain as these two values started |
| 788 | * the same after a fork. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 789 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 790 | if (tsk->exit_signal != SIGCHLD && tsk->exit_signal != -1 && |
| 791 | ( tsk->parent_exec_id != t->self_exec_id || |
| 792 | tsk->self_exec_id != tsk->parent_exec_id) |
| 793 | && !capable(CAP_KILL)) |
| 794 | tsk->exit_signal = SIGCHLD; |
| 795 | |
| 796 | |
| 797 | /* If something other than our normal parent is ptracing us, then |
| 798 | * send it a SIGCHLD instead of honoring exit_signal. exit_signal |
| 799 | * only has special meaning to our real parent. |
| 800 | */ |
| 801 | if (tsk->exit_signal != -1 && thread_group_empty(tsk)) { |
| 802 | int signal = tsk->parent == tsk->real_parent ? tsk->exit_signal : SIGCHLD; |
| 803 | do_notify_parent(tsk, signal); |
| 804 | } else if (tsk->ptrace) { |
| 805 | do_notify_parent(tsk, SIGCHLD); |
| 806 | } |
| 807 | |
| 808 | state = EXIT_ZOMBIE; |
Oleg Nesterov | 2472844 | 2007-08-04 01:04:41 +0400 | [diff] [blame] | 809 | if (tsk->exit_signal == -1 && likely(!tsk->ptrace)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 810 | state = EXIT_DEAD; |
| 811 | tsk->exit_state = state; |
| 812 | |
Oleg Nesterov | 6db840f | 2007-10-16 23:27:23 -0700 | [diff] [blame] | 813 | if (thread_group_leader(tsk) && |
| 814 | tsk->signal->notify_count < 0 && |
| 815 | tsk->signal->group_exit_task) |
| 816 | wake_up_process(tsk->signal->group_exit_task); |
| 817 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 818 | write_unlock_irq(&tasklist_lock); |
| 819 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 820 | /* If the process is dead, release it - nobody will wait for it */ |
| 821 | if (state == EXIT_DEAD) |
| 822 | release_task(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 823 | } |
| 824 | |
Jeff Dike | e18eecb | 2007-07-15 23:38:48 -0700 | [diff] [blame] | 825 | #ifdef CONFIG_DEBUG_STACK_USAGE |
| 826 | static void check_stack_usage(void) |
| 827 | { |
| 828 | static DEFINE_SPINLOCK(low_water_lock); |
| 829 | static int lowest_to_date = THREAD_SIZE; |
| 830 | unsigned long *n = end_of_stack(current); |
| 831 | unsigned long free; |
| 832 | |
| 833 | while (*n == 0) |
| 834 | n++; |
| 835 | free = (unsigned long)n - (unsigned long)end_of_stack(current); |
| 836 | |
| 837 | if (free >= lowest_to_date) |
| 838 | return; |
| 839 | |
| 840 | spin_lock(&low_water_lock); |
| 841 | if (free < lowest_to_date) { |
| 842 | printk(KERN_WARNING "%s used greatest stack depth: %lu bytes " |
| 843 | "left\n", |
| 844 | current->comm, free); |
| 845 | lowest_to_date = free; |
| 846 | } |
| 847 | spin_unlock(&low_water_lock); |
| 848 | } |
| 849 | #else |
| 850 | static inline void check_stack_usage(void) {} |
| 851 | #endif |
| 852 | |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 853 | static inline void exit_child_reaper(struct task_struct *tsk) |
| 854 | { |
Sukadev Bhattiprolu | 88f21d8 | 2007-10-18 23:39:50 -0700 | [diff] [blame] | 855 | if (likely(tsk->group_leader != task_child_reaper(tsk))) |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 856 | return; |
| 857 | |
Sukadev Bhattiprolu | 3eb07c8 | 2007-10-18 23:40:13 -0700 | [diff] [blame] | 858 | if (tsk->nsproxy->pid_ns == &init_pid_ns) |
| 859 | panic("Attempted to kill init!"); |
| 860 | |
| 861 | /* |
| 862 | * @tsk is the last thread in the 'cgroup-init' and is exiting. |
| 863 | * Terminate all remaining processes in the namespace and reap them |
| 864 | * before exiting @tsk. |
| 865 | * |
| 866 | * Note that @tsk (last thread of cgroup-init) may not necessarily |
| 867 | * be the child-reaper (i.e main thread of cgroup-init) of the |
| 868 | * namespace i.e the child_reaper may have already exited. |
| 869 | * |
| 870 | * Even after a child_reaper exits, we let it inherit orphaned children, |
| 871 | * because, pid_ns->child_reaper remains valid as long as there is |
| 872 | * at least one living sub-thread in the cgroup init. |
| 873 | |
| 874 | * This living sub-thread of the cgroup-init will be notified when |
| 875 | * a child inherited by the 'child-reaper' exits (do_notify_parent() |
| 876 | * uses __group_send_sig_info()). Further, when reaping child processes, |
| 877 | * do_wait() iterates over children of all living sub threads. |
| 878 | |
| 879 | * i.e even though 'child_reaper' thread is listed as the parent of the |
| 880 | * orphaned children, any living sub-thread in the cgroup-init can |
| 881 | * perform the role of the child_reaper. |
| 882 | */ |
| 883 | zap_pid_ns_processes(tsk->nsproxy->pid_ns); |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 884 | } |
| 885 | |
Harvey Harrison | 7ad5b3a | 2008-02-08 04:19:53 -0800 | [diff] [blame] | 886 | NORET_TYPE void do_exit(long code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 887 | { |
| 888 | struct task_struct *tsk = current; |
| 889 | int group_dead; |
| 890 | |
| 891 | profile_task_exit(tsk); |
| 892 | |
Jens Axboe | 22e2c50 | 2005-06-27 10:55:12 +0200 | [diff] [blame] | 893 | WARN_ON(atomic_read(&tsk->fs_excl)); |
| 894 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 895 | if (unlikely(in_interrupt())) |
| 896 | panic("Aiee, killing interrupt handler!"); |
| 897 | if (unlikely(!tsk->pid)) |
| 898 | panic("Attempted to kill the idle task!"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 899 | |
| 900 | if (unlikely(current->ptrace & PT_TRACE_EXIT)) { |
| 901 | current->ptrace_message = code; |
| 902 | ptrace_notify((PTRACE_EVENT_EXIT << 8) | SIGTRAP); |
| 903 | } |
| 904 | |
Alexander Nyberg | df164db | 2005-06-23 00:09:13 -0700 | [diff] [blame] | 905 | /* |
| 906 | * We're taking recursive faults here in do_exit. Safest is to just |
| 907 | * leave this task alone and wait for reboot. |
| 908 | */ |
| 909 | if (unlikely(tsk->flags & PF_EXITING)) { |
| 910 | printk(KERN_ALERT |
| 911 | "Fixing recursive fault but reboot is needed!\n"); |
Alexey Kuznetsov | 778e9a9 | 2007-06-08 13:47:00 -0700 | [diff] [blame] | 912 | /* |
| 913 | * We can do this unlocked here. The futex code uses |
| 914 | * this flag just to verify whether the pi state |
| 915 | * cleanup has been done or not. In the worst case it |
| 916 | * loops once more. We pretend that the cleanup was |
| 917 | * done as there is no way to return. Either the |
| 918 | * OWNER_DIED bit is set by now or we push the blocked |
| 919 | * task into the wait for ever nirwana as well. |
| 920 | */ |
| 921 | tsk->flags |= PF_EXITPIDONE; |
Al Viro | afc847b | 2006-02-28 12:51:55 -0500 | [diff] [blame] | 922 | if (tsk->io_context) |
| 923 | exit_io_context(); |
Alexander Nyberg | df164db | 2005-06-23 00:09:13 -0700 | [diff] [blame] | 924 | set_current_state(TASK_UNINTERRUPTIBLE); |
| 925 | schedule(); |
| 926 | } |
| 927 | |
Oleg Nesterov | d12619b | 2008-02-08 04:19:12 -0800 | [diff] [blame] | 928 | exit_signals(tsk); /* sets PF_EXITING */ |
Alexey Kuznetsov | 778e9a9 | 2007-06-08 13:47:00 -0700 | [diff] [blame] | 929 | /* |
| 930 | * tsk->flags are checked in the futex code to protect against |
| 931 | * an exiting task cleaning up the robust pi futexes. |
| 932 | */ |
Oleg Nesterov | d2ee719 | 2007-10-16 23:26:47 -0700 | [diff] [blame] | 933 | smp_mb(); |
| 934 | spin_unlock_wait(&tsk->pi_lock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 936 | if (unlikely(in_atomic())) |
| 937 | printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n", |
Pavel Emelyanov | ba25f9d | 2007-10-18 23:40:40 -0700 | [diff] [blame] | 938 | current->comm, task_pid_nr(current), |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 939 | preempt_count()); |
| 940 | |
| 941 | acct_update_integrals(tsk); |
Hugh Dickins | 365e9c87 | 2005-10-29 18:16:18 -0700 | [diff] [blame] | 942 | if (tsk->mm) { |
| 943 | update_hiwater_rss(tsk->mm); |
| 944 | update_hiwater_vm(tsk->mm); |
| 945 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 946 | group_dead = atomic_dec_and_test(&tsk->signal->live); |
Andrew Morton | c306895 | 2005-08-04 16:49:32 -0700 | [diff] [blame] | 947 | if (group_dead) { |
Oleg Nesterov | 84eb646 | 2007-10-16 23:26:49 -0700 | [diff] [blame] | 948 | exit_child_reaper(tsk); |
Alexey Kuznetsov | 778e9a9 | 2007-06-08 13:47:00 -0700 | [diff] [blame] | 949 | hrtimer_cancel(&tsk->signal->real_timer); |
Roland McGrath | 25f407f | 2005-10-21 15:03:29 -0700 | [diff] [blame] | 950 | exit_itimers(tsk->signal); |
Andrew Morton | c306895 | 2005-08-04 16:49:32 -0700 | [diff] [blame] | 951 | } |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 952 | acct_collect(code, group_dead); |
Alexey Dobriyan | 42b2dd0 | 2007-10-16 23:27:30 -0700 | [diff] [blame] | 953 | #ifdef CONFIG_FUTEX |
Ingo Molnar | 0771dfe | 2006-03-27 01:16:22 -0800 | [diff] [blame] | 954 | if (unlikely(tsk->robust_list)) |
| 955 | exit_robust_list(tsk); |
Alexey Dobriyan | 42b2dd0 | 2007-10-16 23:27:30 -0700 | [diff] [blame] | 956 | #ifdef CONFIG_COMPAT |
Ingo Molnar | 34f192c | 2006-03-27 01:16:24 -0800 | [diff] [blame] | 957 | if (unlikely(tsk->compat_robust_list)) |
| 958 | compat_exit_robust_list(tsk); |
| 959 | #endif |
Alexey Dobriyan | 42b2dd0 | 2007-10-16 23:27:30 -0700 | [diff] [blame] | 960 | #endif |
Miloslav Trmac | 522ed77 | 2007-07-15 23:40:56 -0700 | [diff] [blame] | 961 | if (group_dead) |
| 962 | tty_audit_exit(); |
Al Viro | fa84cb9 | 2006-03-29 20:30:19 -0500 | [diff] [blame] | 963 | if (unlikely(tsk->audit_context)) |
| 964 | audit_free(tsk); |
Oleg Nesterov | 115085e | 2006-12-06 20:36:51 -0800 | [diff] [blame] | 965 | |
Jonathan Lim | f2ab6d8 | 2007-08-30 23:56:23 -0700 | [diff] [blame] | 966 | tsk->exit_code = code; |
Oleg Nesterov | 115085e | 2006-12-06 20:36:51 -0800 | [diff] [blame] | 967 | taskstats_exit(tsk, group_dead); |
Shailabh Nagar | c757249 | 2006-07-14 00:24:40 -0700 | [diff] [blame] | 968 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | exit_mm(tsk); |
| 970 | |
KaiGai Kohei | 0e46481 | 2006-06-25 05:49:24 -0700 | [diff] [blame] | 971 | if (group_dead) |
KaiGai Kohei | f6ec29a | 2006-06-25 05:49:25 -0700 | [diff] [blame] | 972 | acct_process(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 973 | exit_sem(tsk); |
| 974 | __exit_files(tsk); |
| 975 | __exit_fs(tsk); |
Jeff Dike | e18eecb | 2007-07-15 23:38:48 -0700 | [diff] [blame] | 976 | check_stack_usage(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 977 | exit_thread(); |
Paul Menage | b4f48b6 | 2007-10-18 23:39:33 -0700 | [diff] [blame] | 978 | cgroup_exit(tsk, 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 979 | exit_keys(tsk); |
| 980 | |
| 981 | if (group_dead && tsk->signal->leader) |
| 982 | disassociate_ctty(1); |
| 983 | |
Al Viro | a1261f5 | 2005-11-13 16:06:55 -0800 | [diff] [blame] | 984 | module_put(task_thread_info(tsk)->exec_domain->module); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 985 | if (tsk->binfmt) |
| 986 | module_put(tsk->binfmt->module); |
| 987 | |
Matt Helsley | 9f46080 | 2005-11-07 00:59:16 -0800 | [diff] [blame] | 988 | proc_exit_connector(tsk); |
Serge E. Hallyn | 0f24528 | 2007-01-30 15:28:23 -0600 | [diff] [blame] | 989 | exit_notify(tsk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 990 | #ifdef CONFIG_NUMA |
| 991 | mpol_free(tsk->mempolicy); |
| 992 | tsk->mempolicy = NULL; |
| 993 | #endif |
Alexey Dobriyan | 42b2dd0 | 2007-10-16 23:27:30 -0700 | [diff] [blame] | 994 | #ifdef CONFIG_FUTEX |
Ingo Molnar | de5097c | 2006-01-09 15:59:21 -0800 | [diff] [blame] | 995 | /* |
Ingo Molnar | c87e283 | 2006-06-27 02:54:58 -0700 | [diff] [blame] | 996 | * This must happen late, after the PID is not |
| 997 | * hashed anymore: |
| 998 | */ |
| 999 | if (unlikely(!list_empty(&tsk->pi_state_list))) |
| 1000 | exit_pi_state_list(tsk); |
| 1001 | if (unlikely(current->pi_state_cache)) |
| 1002 | kfree(current->pi_state_cache); |
Alexey Dobriyan | 42b2dd0 | 2007-10-16 23:27:30 -0700 | [diff] [blame] | 1003 | #endif |
Ingo Molnar | c87e283 | 2006-06-27 02:54:58 -0700 | [diff] [blame] | 1004 | /* |
Ingo Molnar | 9a11b49a | 2006-07-03 00:24:33 -0700 | [diff] [blame] | 1005 | * Make sure we are holding no locks: |
Ingo Molnar | de5097c | 2006-01-09 15:59:21 -0800 | [diff] [blame] | 1006 | */ |
Ingo Molnar | 9a11b49a | 2006-07-03 00:24:33 -0700 | [diff] [blame] | 1007 | debug_check_no_locks_held(tsk); |
Alexey Kuznetsov | 778e9a9 | 2007-06-08 13:47:00 -0700 | [diff] [blame] | 1008 | /* |
| 1009 | * We can do this unlocked here. The futex code uses this flag |
| 1010 | * just to verify whether the pi state cleanup has been done |
| 1011 | * or not. In the worst case it loops once more. |
| 1012 | */ |
| 1013 | tsk->flags |= PF_EXITPIDONE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1014 | |
Al Viro | afc847b | 2006-02-28 12:51:55 -0500 | [diff] [blame] | 1015 | if (tsk->io_context) |
| 1016 | exit_io_context(); |
| 1017 | |
Jens Axboe | b92ce55 | 2006-04-11 13:52:07 +0200 | [diff] [blame] | 1018 | if (tsk->splice_pipe) |
| 1019 | __free_pipe_info(tsk->splice_pipe); |
| 1020 | |
Coywolf Qi Hunt | 7407251 | 2005-10-30 15:02:47 -0800 | [diff] [blame] | 1021 | preempt_disable(); |
Oleg Nesterov | 55a101f | 2006-09-29 02:01:10 -0700 | [diff] [blame] | 1022 | /* causes final put_task_struct in finish_task_switch(). */ |
Oleg Nesterov | c394cc9 | 2006-09-29 02:01:11 -0700 | [diff] [blame] | 1023 | tsk->state = TASK_DEAD; |
Coywolf Qi Hunt | 7407251 | 2005-10-30 15:02:47 -0800 | [diff] [blame] | 1024 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1025 | schedule(); |
| 1026 | BUG(); |
| 1027 | /* Avoid "noreturn function does return". */ |
Alan Cox | 54306cf | 2006-09-29 02:00:42 -0700 | [diff] [blame] | 1028 | for (;;) |
| 1029 | cpu_relax(); /* For when BUG is null */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1030 | } |
| 1031 | |
Russ Anderson | 012914d | 2005-04-23 00:08:00 -0700 | [diff] [blame] | 1032 | EXPORT_SYMBOL_GPL(do_exit); |
| 1033 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1034 | NORET_TYPE void complete_and_exit(struct completion *comp, long code) |
| 1035 | { |
| 1036 | if (comp) |
| 1037 | complete(comp); |
Oleg Nesterov | 55a101f | 2006-09-29 02:01:10 -0700 | [diff] [blame] | 1038 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1039 | do_exit(code); |
| 1040 | } |
| 1041 | |
| 1042 | EXPORT_SYMBOL(complete_and_exit); |
| 1043 | |
| 1044 | asmlinkage long sys_exit(int error_code) |
| 1045 | { |
| 1046 | do_exit((error_code&0xff)<<8); |
| 1047 | } |
| 1048 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1049 | /* |
| 1050 | * Take down every thread in the group. This is called by fatal signals |
| 1051 | * as well as by sys_exit_group (below). |
| 1052 | */ |
| 1053 | NORET_TYPE void |
| 1054 | do_group_exit(int exit_code) |
| 1055 | { |
| 1056 | BUG_ON(exit_code & 0x80); /* core dumps don't get here */ |
| 1057 | |
| 1058 | if (current->signal->flags & SIGNAL_GROUP_EXIT) |
| 1059 | exit_code = current->signal->group_exit_code; |
| 1060 | else if (!thread_group_empty(current)) { |
| 1061 | struct signal_struct *const sig = current->signal; |
| 1062 | struct sighand_struct *const sighand = current->sighand; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1063 | spin_lock_irq(&sighand->siglock); |
Oleg Nesterov | ed5d2ca | 2008-02-04 22:27:24 -0800 | [diff] [blame] | 1064 | if (signal_group_exit(sig)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1065 | /* Another thread got here before we took the lock. */ |
| 1066 | exit_code = sig->group_exit_code; |
| 1067 | else { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1068 | sig->group_exit_code = exit_code; |
Oleg Nesterov | ed5d2ca | 2008-02-04 22:27:24 -0800 | [diff] [blame] | 1069 | sig->flags = SIGNAL_GROUP_EXIT; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1070 | zap_other_threads(current); |
| 1071 | } |
| 1072 | spin_unlock_irq(&sighand->siglock); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1073 | } |
| 1074 | |
| 1075 | do_exit(exit_code); |
| 1076 | /* NOTREACHED */ |
| 1077 | } |
| 1078 | |
| 1079 | /* |
| 1080 | * this kills every thread in the thread group. Note that any externally |
| 1081 | * wait4()-ing process will get the correct exit code - even if this |
| 1082 | * thread is not the thread group leader. |
| 1083 | */ |
| 1084 | asmlinkage void sys_exit_group(int error_code) |
| 1085 | { |
| 1086 | do_group_exit((error_code & 0xff) << 8); |
| 1087 | } |
| 1088 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1089 | static struct pid *task_pid_type(struct task_struct *task, enum pid_type type) |
| 1090 | { |
| 1091 | struct pid *pid = NULL; |
| 1092 | if (type == PIDTYPE_PID) |
| 1093 | pid = task->pids[type].pid; |
| 1094 | else if (type < PIDTYPE_MAX) |
| 1095 | pid = task->group_leader->pids[type].pid; |
| 1096 | return pid; |
| 1097 | } |
| 1098 | |
| 1099 | static int eligible_child(enum pid_type type, struct pid *pid, int options, |
| 1100 | struct task_struct *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1101 | { |
Roland McGrath | 7324328 | 2007-05-06 14:50:20 -0700 | [diff] [blame] | 1102 | int err; |
| 1103 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1104 | if (type < PIDTYPE_MAX) { |
| 1105 | if (task_pid_type(p, type) != pid) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1106 | return 0; |
| 1107 | } |
| 1108 | |
| 1109 | /* |
| 1110 | * Do not consider detached threads that are |
| 1111 | * not ptraced: |
| 1112 | */ |
| 1113 | if (p->exit_signal == -1 && !p->ptrace) |
| 1114 | return 0; |
| 1115 | |
| 1116 | /* Wait for all children (clone and not) if __WALL is set; |
| 1117 | * otherwise, wait for clone children *only* if __WCLONE is |
| 1118 | * set; otherwise, wait for non-clone children *only*. (Note: |
| 1119 | * A "clone" child here is one that reports to its parent |
| 1120 | * using a signal other than SIGCHLD.) */ |
| 1121 | if (((p->exit_signal != SIGCHLD) ^ ((options & __WCLONE) != 0)) |
| 1122 | && !(options & __WALL)) |
| 1123 | return 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1124 | |
Roland McGrath | 7324328 | 2007-05-06 14:50:20 -0700 | [diff] [blame] | 1125 | err = security_task_wait(p); |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1126 | if (likely(!err)) |
| 1127 | return 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1129 | if (type != PIDTYPE_PID) |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1130 | return 0; |
| 1131 | /* This child was explicitly requested, abort */ |
| 1132 | read_unlock(&tasklist_lock); |
| 1133 | return err; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1134 | } |
| 1135 | |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1136 | static int wait_noreap_copyout(struct task_struct *p, pid_t pid, uid_t uid, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1137 | int why, int status, |
| 1138 | struct siginfo __user *infop, |
| 1139 | struct rusage __user *rusagep) |
| 1140 | { |
| 1141 | int retval = rusagep ? getrusage(p, RUSAGE_BOTH, rusagep) : 0; |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1142 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1143 | put_task_struct(p); |
| 1144 | if (!retval) |
| 1145 | retval = put_user(SIGCHLD, &infop->si_signo); |
| 1146 | if (!retval) |
| 1147 | retval = put_user(0, &infop->si_errno); |
| 1148 | if (!retval) |
| 1149 | retval = put_user((short)why, &infop->si_code); |
| 1150 | if (!retval) |
| 1151 | retval = put_user(pid, &infop->si_pid); |
| 1152 | if (!retval) |
| 1153 | retval = put_user(uid, &infop->si_uid); |
| 1154 | if (!retval) |
| 1155 | retval = put_user(status, &infop->si_status); |
| 1156 | if (!retval) |
| 1157 | retval = pid; |
| 1158 | return retval; |
| 1159 | } |
| 1160 | |
| 1161 | /* |
| 1162 | * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold |
| 1163 | * read_lock(&tasklist_lock) on entry. If we return zero, we still hold |
| 1164 | * the lock and this task is uninteresting. If we return nonzero, we have |
| 1165 | * released the lock and the system call should return. |
| 1166 | */ |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1167 | static int wait_task_zombie(struct task_struct *p, int noreap, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1168 | struct siginfo __user *infop, |
| 1169 | int __user *stat_addr, struct rusage __user *ru) |
| 1170 | { |
| 1171 | unsigned long state; |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1172 | int retval, status, traced; |
Pavel Emelyanov | 6c5f3e7 | 2008-02-08 04:19:20 -0800 | [diff] [blame] | 1173 | pid_t pid = task_pid_vnr(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1174 | |
| 1175 | if (unlikely(noreap)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1176 | uid_t uid = p->uid; |
| 1177 | int exit_code = p->exit_code; |
| 1178 | int why, status; |
| 1179 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1180 | get_task_struct(p); |
| 1181 | read_unlock(&tasklist_lock); |
| 1182 | if ((exit_code & 0x7f) == 0) { |
| 1183 | why = CLD_EXITED; |
| 1184 | status = exit_code >> 8; |
| 1185 | } else { |
| 1186 | why = (exit_code & 0x80) ? CLD_DUMPED : CLD_KILLED; |
| 1187 | status = exit_code & 0x7f; |
| 1188 | } |
| 1189 | return wait_noreap_copyout(p, pid, uid, why, |
| 1190 | status, infop, ru); |
| 1191 | } |
| 1192 | |
| 1193 | /* |
| 1194 | * Try to move the task's state to DEAD |
| 1195 | * only one thread is allowed to do this: |
| 1196 | */ |
| 1197 | state = xchg(&p->exit_state, EXIT_DEAD); |
| 1198 | if (state != EXIT_ZOMBIE) { |
| 1199 | BUG_ON(state != EXIT_DEAD); |
| 1200 | return 0; |
| 1201 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1202 | |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1203 | /* traced means p->ptrace, but not vice versa */ |
| 1204 | traced = (p->real_parent != p->parent); |
| 1205 | |
| 1206 | if (likely(!traced)) { |
Jesper Juhl | 3795e16 | 2006-01-09 20:54:39 -0800 | [diff] [blame] | 1207 | struct signal_struct *psig; |
| 1208 | struct signal_struct *sig; |
| 1209 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1210 | /* |
| 1211 | * The resource counters for the group leader are in its |
| 1212 | * own task_struct. Those for dead threads in the group |
| 1213 | * are in its signal_struct, as are those for the child |
| 1214 | * processes it has previously reaped. All these |
| 1215 | * accumulate in the parent's signal_struct c* fields. |
| 1216 | * |
| 1217 | * We don't bother to take a lock here to protect these |
| 1218 | * p->signal fields, because they are only touched by |
| 1219 | * __exit_signal, which runs with tasklist_lock |
| 1220 | * write-locked anyway, and so is excluded here. We do |
| 1221 | * need to protect the access to p->parent->signal fields, |
| 1222 | * as other threads in the parent group can be right |
| 1223 | * here reaping other children at the same time. |
| 1224 | */ |
| 1225 | spin_lock_irq(&p->parent->sighand->siglock); |
Jesper Juhl | 3795e16 | 2006-01-09 20:54:39 -0800 | [diff] [blame] | 1226 | psig = p->parent->signal; |
| 1227 | sig = p->signal; |
| 1228 | psig->cutime = |
| 1229 | cputime_add(psig->cutime, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1230 | cputime_add(p->utime, |
Jesper Juhl | 3795e16 | 2006-01-09 20:54:39 -0800 | [diff] [blame] | 1231 | cputime_add(sig->utime, |
| 1232 | sig->cutime))); |
| 1233 | psig->cstime = |
| 1234 | cputime_add(psig->cstime, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1235 | cputime_add(p->stime, |
Jesper Juhl | 3795e16 | 2006-01-09 20:54:39 -0800 | [diff] [blame] | 1236 | cputime_add(sig->stime, |
| 1237 | sig->cstime))); |
Laurent Vivier | 9ac5231 | 2007-10-15 17:00:19 +0200 | [diff] [blame] | 1238 | psig->cgtime = |
| 1239 | cputime_add(psig->cgtime, |
| 1240 | cputime_add(p->gtime, |
| 1241 | cputime_add(sig->gtime, |
| 1242 | sig->cgtime))); |
Jesper Juhl | 3795e16 | 2006-01-09 20:54:39 -0800 | [diff] [blame] | 1243 | psig->cmin_flt += |
| 1244 | p->min_flt + sig->min_flt + sig->cmin_flt; |
| 1245 | psig->cmaj_flt += |
| 1246 | p->maj_flt + sig->maj_flt + sig->cmaj_flt; |
| 1247 | psig->cnvcsw += |
| 1248 | p->nvcsw + sig->nvcsw + sig->cnvcsw; |
| 1249 | psig->cnivcsw += |
| 1250 | p->nivcsw + sig->nivcsw + sig->cnivcsw; |
Eric Dumazet | 6eaeeab | 2007-05-10 22:22:37 -0700 | [diff] [blame] | 1251 | psig->cinblock += |
| 1252 | task_io_get_inblock(p) + |
| 1253 | sig->inblock + sig->cinblock; |
| 1254 | psig->coublock += |
| 1255 | task_io_get_oublock(p) + |
| 1256 | sig->oublock + sig->coublock; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1257 | spin_unlock_irq(&p->parent->sighand->siglock); |
| 1258 | } |
| 1259 | |
| 1260 | /* |
| 1261 | * Now we are sure this task is interesting, and no other |
| 1262 | * thread can reap it because we set its state to EXIT_DEAD. |
| 1263 | */ |
| 1264 | read_unlock(&tasklist_lock); |
| 1265 | |
| 1266 | retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; |
| 1267 | status = (p->signal->flags & SIGNAL_GROUP_EXIT) |
| 1268 | ? p->signal->group_exit_code : p->exit_code; |
| 1269 | if (!retval && stat_addr) |
| 1270 | retval = put_user(status, stat_addr); |
| 1271 | if (!retval && infop) |
| 1272 | retval = put_user(SIGCHLD, &infop->si_signo); |
| 1273 | if (!retval && infop) |
| 1274 | retval = put_user(0, &infop->si_errno); |
| 1275 | if (!retval && infop) { |
| 1276 | int why; |
| 1277 | |
| 1278 | if ((status & 0x7f) == 0) { |
| 1279 | why = CLD_EXITED; |
| 1280 | status >>= 8; |
| 1281 | } else { |
| 1282 | why = (status & 0x80) ? CLD_DUMPED : CLD_KILLED; |
| 1283 | status &= 0x7f; |
| 1284 | } |
| 1285 | retval = put_user((short)why, &infop->si_code); |
| 1286 | if (!retval) |
| 1287 | retval = put_user(status, &infop->si_status); |
| 1288 | } |
| 1289 | if (!retval && infop) |
Oleg Nesterov | 3a515e4 | 2008-02-08 04:19:07 -0800 | [diff] [blame] | 1290 | retval = put_user(pid, &infop->si_pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1291 | if (!retval && infop) |
| 1292 | retval = put_user(p->uid, &infop->si_uid); |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1293 | if (!retval) |
Oleg Nesterov | 3a515e4 | 2008-02-08 04:19:07 -0800 | [diff] [blame] | 1294 | retval = pid; |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1295 | |
| 1296 | if (traced) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1297 | write_lock_irq(&tasklist_lock); |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1298 | /* We dropped tasklist, ptracer could die and untrace */ |
| 1299 | ptrace_unlink(p); |
| 1300 | /* |
| 1301 | * If this is not a detached task, notify the parent. |
| 1302 | * If it's still not detached after that, don't release |
| 1303 | * it now. |
| 1304 | */ |
| 1305 | if (p->exit_signal != -1) { |
| 1306 | do_notify_parent(p, p->exit_signal); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1307 | if (p->exit_signal != -1) { |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1308 | p->exit_state = EXIT_ZOMBIE; |
| 1309 | p = NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | } |
| 1311 | } |
| 1312 | write_unlock_irq(&tasklist_lock); |
| 1313 | } |
| 1314 | if (p != NULL) |
| 1315 | release_task(p); |
Oleg Nesterov | 2f4e6e2 | 2007-10-16 23:26:58 -0700 | [diff] [blame] | 1316 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1317 | return retval; |
| 1318 | } |
| 1319 | |
| 1320 | /* |
| 1321 | * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold |
| 1322 | * read_lock(&tasklist_lock) on entry. If we return zero, we still hold |
| 1323 | * the lock and this task is uninteresting. If we return nonzero, we have |
| 1324 | * released the lock and the system call should return. |
| 1325 | */ |
Oleg Nesterov | 1bad95c | 2008-02-08 04:19:03 -0800 | [diff] [blame] | 1326 | static int wait_task_stopped(struct task_struct *p, |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1327 | int noreap, struct siginfo __user *infop, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1328 | int __user *stat_addr, struct rusage __user *ru) |
| 1329 | { |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1330 | int retval, exit_code, why; |
| 1331 | uid_t uid = 0; /* unneeded, required by compiler */ |
Oleg Nesterov | c895078 | 2007-11-28 16:21:24 -0800 | [diff] [blame] | 1332 | pid_t pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1334 | exit_code = 0; |
| 1335 | spin_lock_irq(&p->sighand->siglock); |
| 1336 | |
| 1337 | if (unlikely(!task_is_stopped_or_traced(p))) |
| 1338 | goto unlock_sig; |
| 1339 | |
Oleg Nesterov | 1bad95c | 2008-02-08 04:19:03 -0800 | [diff] [blame] | 1340 | if (!(p->ptrace & PT_PTRACED) && p->signal->group_stop_count > 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1341 | /* |
| 1342 | * A group stop is in progress and this is the group leader. |
| 1343 | * We won't report until all threads have stopped. |
| 1344 | */ |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1345 | goto unlock_sig; |
| 1346 | |
| 1347 | exit_code = p->exit_code; |
| 1348 | if (!exit_code) |
| 1349 | goto unlock_sig; |
| 1350 | |
| 1351 | if (!noreap) |
| 1352 | p->exit_code = 0; |
| 1353 | |
| 1354 | uid = p->uid; |
| 1355 | unlock_sig: |
| 1356 | spin_unlock_irq(&p->sighand->siglock); |
| 1357 | if (!exit_code) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1358 | return 0; |
| 1359 | |
| 1360 | /* |
| 1361 | * Now we are pretty sure this task is interesting. |
| 1362 | * Make sure it doesn't get reaped out from under us while we |
| 1363 | * give up the lock and then examine it below. We don't want to |
| 1364 | * keep holding onto the tasklist_lock while we call getrusage and |
| 1365 | * possibly take page faults for user memory. |
| 1366 | */ |
| 1367 | get_task_struct(p); |
Pavel Emelyanov | 6c5f3e7 | 2008-02-08 04:19:20 -0800 | [diff] [blame] | 1368 | pid = task_pid_vnr(p); |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1369 | why = (p->ptrace & PT_PTRACED) ? CLD_TRAPPED : CLD_STOPPED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1370 | read_unlock(&tasklist_lock); |
| 1371 | |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1372 | if (unlikely(noreap)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1373 | return wait_noreap_copyout(p, pid, uid, |
Scott James Remnant | e6ceb32 | 2007-11-28 16:22:07 -0800 | [diff] [blame] | 1374 | why, exit_code, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1375 | infop, ru); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1376 | |
| 1377 | retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; |
| 1378 | if (!retval && stat_addr) |
| 1379 | retval = put_user((exit_code << 8) | 0x7f, stat_addr); |
| 1380 | if (!retval && infop) |
| 1381 | retval = put_user(SIGCHLD, &infop->si_signo); |
| 1382 | if (!retval && infop) |
| 1383 | retval = put_user(0, &infop->si_errno); |
| 1384 | if (!retval && infop) |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1385 | retval = put_user(why, &infop->si_code); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1386 | if (!retval && infop) |
| 1387 | retval = put_user(exit_code, &infop->si_status); |
| 1388 | if (!retval && infop) |
Oleg Nesterov | c895078 | 2007-11-28 16:21:24 -0800 | [diff] [blame] | 1389 | retval = put_user(pid, &infop->si_pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1390 | if (!retval && infop) |
Oleg Nesterov | ee7c82d | 2008-02-08 04:19:01 -0800 | [diff] [blame] | 1391 | retval = put_user(uid, &infop->si_uid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1392 | if (!retval) |
Oleg Nesterov | c895078 | 2007-11-28 16:21:24 -0800 | [diff] [blame] | 1393 | retval = pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1394 | put_task_struct(p); |
| 1395 | |
| 1396 | BUG_ON(!retval); |
| 1397 | return retval; |
| 1398 | } |
| 1399 | |
| 1400 | /* |
| 1401 | * Handle do_wait work for one task in a live, non-stopped state. |
| 1402 | * read_lock(&tasklist_lock) on entry. If we return zero, we still hold |
| 1403 | * the lock and this task is uninteresting. If we return nonzero, we have |
| 1404 | * released the lock and the system call should return. |
| 1405 | */ |
Ingo Molnar | 36c8b58 | 2006-07-03 00:25:41 -0700 | [diff] [blame] | 1406 | static int wait_task_continued(struct task_struct *p, int noreap, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1407 | struct siginfo __user *infop, |
| 1408 | int __user *stat_addr, struct rusage __user *ru) |
| 1409 | { |
| 1410 | int retval; |
| 1411 | pid_t pid; |
| 1412 | uid_t uid; |
| 1413 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1414 | if (!(p->signal->flags & SIGNAL_STOP_CONTINUED)) |
| 1415 | return 0; |
| 1416 | |
| 1417 | spin_lock_irq(&p->sighand->siglock); |
| 1418 | /* Re-check with the lock held. */ |
| 1419 | if (!(p->signal->flags & SIGNAL_STOP_CONTINUED)) { |
| 1420 | spin_unlock_irq(&p->sighand->siglock); |
| 1421 | return 0; |
| 1422 | } |
| 1423 | if (!noreap) |
| 1424 | p->signal->flags &= ~SIGNAL_STOP_CONTINUED; |
| 1425 | spin_unlock_irq(&p->sighand->siglock); |
| 1426 | |
Pavel Emelyanov | 6c5f3e7 | 2008-02-08 04:19:20 -0800 | [diff] [blame] | 1427 | pid = task_pid_vnr(p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1428 | uid = p->uid; |
| 1429 | get_task_struct(p); |
| 1430 | read_unlock(&tasklist_lock); |
| 1431 | |
| 1432 | if (!infop) { |
| 1433 | retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; |
| 1434 | put_task_struct(p); |
| 1435 | if (!retval && stat_addr) |
| 1436 | retval = put_user(0xffff, stat_addr); |
| 1437 | if (!retval) |
Oleg Nesterov | 3a515e4 | 2008-02-08 04:19:07 -0800 | [diff] [blame] | 1438 | retval = pid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1439 | } else { |
| 1440 | retval = wait_noreap_copyout(p, pid, uid, |
| 1441 | CLD_CONTINUED, SIGCONT, |
| 1442 | infop, ru); |
| 1443 | BUG_ON(retval == 0); |
| 1444 | } |
| 1445 | |
| 1446 | return retval; |
| 1447 | } |
| 1448 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1449 | static long do_wait(enum pid_type type, struct pid *pid, int options, |
| 1450 | struct siginfo __user *infop, int __user *stat_addr, |
| 1451 | struct rusage __user *ru) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1452 | { |
| 1453 | DECLARE_WAITQUEUE(wait, current); |
| 1454 | struct task_struct *tsk; |
| 1455 | int flag, retval; |
| 1456 | |
| 1457 | add_wait_queue(¤t->signal->wait_chldexit,&wait); |
| 1458 | repeat: |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1459 | /* If there is nothing that can match our critier just get out */ |
| 1460 | retval = -ECHILD; |
| 1461 | if ((type < PIDTYPE_MAX) && (!pid || hlist_empty(&pid->tasks[type]))) |
| 1462 | goto end; |
| 1463 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1464 | /* |
| 1465 | * We will set this flag if we see any child that might later |
| 1466 | * match our criteria, even if we are not able to reap it yet. |
| 1467 | */ |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1468 | flag = retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1469 | current->state = TASK_INTERRUPTIBLE; |
| 1470 | read_lock(&tasklist_lock); |
| 1471 | tsk = current; |
| 1472 | do { |
| 1473 | struct task_struct *p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1474 | |
Matthias Kaehlcke | 03ff179 | 2007-10-18 23:39:57 -0700 | [diff] [blame] | 1475 | list_for_each_entry(p, &tsk->children, sibling) { |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1476 | int ret = eligible_child(type, pid, options, p); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1477 | if (!ret) |
| 1478 | continue; |
| 1479 | |
Roland McGrath | 7324328 | 2007-05-06 14:50:20 -0700 | [diff] [blame] | 1480 | if (unlikely(ret < 0)) { |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1481 | retval = ret; |
| 1482 | } else if (task_is_stopped_or_traced(p)) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1483 | /* |
| 1484 | * It's stopped now, so it might later |
| 1485 | * continue, exit, or stop again. |
| 1486 | */ |
| 1487 | flag = 1; |
Oleg Nesterov | 34a1738 | 2008-02-08 04:18:59 -0800 | [diff] [blame] | 1488 | if (!(p->ptrace & PT_PTRACED) && |
| 1489 | !(options & WUNTRACED)) |
| 1490 | continue; |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1491 | |
Oleg Nesterov | 1bad95c | 2008-02-08 04:19:03 -0800 | [diff] [blame] | 1492 | retval = wait_task_stopped(p, |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1493 | (options & WNOWAIT), infop, |
| 1494 | stat_addr, ru); |
Oleg Nesterov | 96fabbf | 2008-02-08 04:19:04 -0800 | [diff] [blame] | 1495 | } else if (p->exit_state == EXIT_ZOMBIE && |
| 1496 | !delay_group_leader(p)) { |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1497 | /* |
Oleg Nesterov | 96fabbf | 2008-02-08 04:19:04 -0800 | [diff] [blame] | 1498 | * We don't reap group leaders with subthreads. |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1499 | */ |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1500 | if (!likely(options & WEXITED)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1501 | continue; |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1502 | retval = wait_task_zombie(p, |
| 1503 | (options & WNOWAIT), infop, |
| 1504 | stat_addr, ru); |
Oleg Nesterov | 0a76fe8 | 2008-02-06 01:37:06 -0800 | [diff] [blame] | 1505 | } else if (p->exit_state != EXIT_DEAD) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1506 | /* |
| 1507 | * It's running now, so it might later |
| 1508 | * exit, stop, or stop and then continue. |
| 1509 | */ |
| 1510 | flag = 1; |
| 1511 | if (!unlikely(options & WCONTINUED)) |
| 1512 | continue; |
Matthew Wilcox | 338077e | 2007-12-06 11:09:35 -0500 | [diff] [blame] | 1513 | retval = wait_task_continued(p, |
| 1514 | (options & WNOWAIT), infop, |
| 1515 | stat_addr, ru); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1516 | } |
Oleg Nesterov | 9cbab81 | 2008-02-08 04:19:02 -0800 | [diff] [blame] | 1517 | if (retval != 0) /* tasklist_lock released */ |
| 1518 | goto end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1519 | } |
| 1520 | if (!flag) { |
Matthias Kaehlcke | 03ff179 | 2007-10-18 23:39:57 -0700 | [diff] [blame] | 1521 | list_for_each_entry(p, &tsk->ptrace_children, |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1522 | ptrace_list) { |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1523 | flag = eligible_child(type, pid, options, p); |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1524 | if (!flag) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1525 | continue; |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1526 | if (likely(flag > 0)) |
| 1527 | break; |
| 1528 | retval = flag; |
| 1529 | goto end; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1530 | } |
| 1531 | } |
| 1532 | if (options & __WNOTHREAD) |
| 1533 | break; |
| 1534 | tsk = next_thread(tsk); |
Eric Sesterhenn | 125e187 | 2006-06-23 02:06:06 -0700 | [diff] [blame] | 1535 | BUG_ON(tsk->signal != current->signal); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1536 | } while (tsk != current); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1537 | read_unlock(&tasklist_lock); |
Oleg Nesterov | f2cc3eb | 2008-02-08 04:19:06 -0800 | [diff] [blame] | 1538 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1539 | if (flag) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1540 | if (options & WNOHANG) |
| 1541 | goto end; |
| 1542 | retval = -ERESTARTSYS; |
| 1543 | if (signal_pending(current)) |
| 1544 | goto end; |
| 1545 | schedule(); |
| 1546 | goto repeat; |
| 1547 | } |
| 1548 | retval = -ECHILD; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1549 | end: |
| 1550 | current->state = TASK_RUNNING; |
| 1551 | remove_wait_queue(¤t->signal->wait_chldexit,&wait); |
| 1552 | if (infop) { |
| 1553 | if (retval > 0) |
Oleg Nesterov | 9cbab81 | 2008-02-08 04:19:02 -0800 | [diff] [blame] | 1554 | retval = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1555 | else { |
| 1556 | /* |
| 1557 | * For a WNOHANG return, clear out all the fields |
| 1558 | * we would set so the user can easily tell the |
| 1559 | * difference. |
| 1560 | */ |
| 1561 | if (!retval) |
| 1562 | retval = put_user(0, &infop->si_signo); |
| 1563 | if (!retval) |
| 1564 | retval = put_user(0, &infop->si_errno); |
| 1565 | if (!retval) |
| 1566 | retval = put_user(0, &infop->si_code); |
| 1567 | if (!retval) |
| 1568 | retval = put_user(0, &infop->si_pid); |
| 1569 | if (!retval) |
| 1570 | retval = put_user(0, &infop->si_uid); |
| 1571 | if (!retval) |
| 1572 | retval = put_user(0, &infop->si_status); |
| 1573 | } |
| 1574 | } |
| 1575 | return retval; |
| 1576 | } |
| 1577 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1578 | asmlinkage long sys_waitid(int which, pid_t upid, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1579 | struct siginfo __user *infop, int options, |
| 1580 | struct rusage __user *ru) |
| 1581 | { |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1582 | struct pid *pid = NULL; |
| 1583 | enum pid_type type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1584 | long ret; |
| 1585 | |
| 1586 | if (options & ~(WNOHANG|WNOWAIT|WEXITED|WSTOPPED|WCONTINUED)) |
| 1587 | return -EINVAL; |
| 1588 | if (!(options & (WEXITED|WSTOPPED|WCONTINUED))) |
| 1589 | return -EINVAL; |
| 1590 | |
| 1591 | switch (which) { |
| 1592 | case P_ALL: |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1593 | type = PIDTYPE_MAX; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1594 | break; |
| 1595 | case P_PID: |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1596 | type = PIDTYPE_PID; |
| 1597 | if (upid <= 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1598 | return -EINVAL; |
| 1599 | break; |
| 1600 | case P_PGID: |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1601 | type = PIDTYPE_PGID; |
| 1602 | if (upid <= 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1603 | return -EINVAL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1604 | break; |
| 1605 | default: |
| 1606 | return -EINVAL; |
| 1607 | } |
| 1608 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1609 | if (type < PIDTYPE_MAX) |
| 1610 | pid = find_get_pid(upid); |
| 1611 | ret = do_wait(type, pid, options, infop, NULL, ru); |
| 1612 | put_pid(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1613 | |
| 1614 | /* avoid REGPARM breakage on x86: */ |
| 1615 | prevent_tail_call(ret); |
| 1616 | return ret; |
| 1617 | } |
| 1618 | |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1619 | asmlinkage long sys_wait4(pid_t upid, int __user *stat_addr, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1620 | int options, struct rusage __user *ru) |
| 1621 | { |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1622 | struct pid *pid = NULL; |
| 1623 | enum pid_type type; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1624 | long ret; |
| 1625 | |
| 1626 | if (options & ~(WNOHANG|WUNTRACED|WCONTINUED| |
| 1627 | __WNOTHREAD|__WCLONE|__WALL)) |
| 1628 | return -EINVAL; |
Eric W. Biederman | 161550d | 2008-02-08 04:19:14 -0800 | [diff] [blame] | 1629 | |
| 1630 | if (upid == -1) |
| 1631 | type = PIDTYPE_MAX; |
| 1632 | else if (upid < 0) { |
| 1633 | type = PIDTYPE_PGID; |
| 1634 | pid = find_get_pid(-upid); |
| 1635 | } else if (upid == 0) { |
| 1636 | type = PIDTYPE_PGID; |
| 1637 | pid = get_pid(task_pgrp(current)); |
| 1638 | } else /* upid > 0 */ { |
| 1639 | type = PIDTYPE_PID; |
| 1640 | pid = find_get_pid(upid); |
| 1641 | } |
| 1642 | |
| 1643 | ret = do_wait(type, pid, options | WEXITED, NULL, stat_addr, ru); |
| 1644 | put_pid(pid); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1645 | |
| 1646 | /* avoid REGPARM breakage on x86: */ |
| 1647 | prevent_tail_call(ret); |
| 1648 | return ret; |
| 1649 | } |
| 1650 | |
| 1651 | #ifdef __ARCH_WANT_SYS_WAITPID |
| 1652 | |
| 1653 | /* |
| 1654 | * sys_waitpid() remains for compatibility. waitpid() should be |
| 1655 | * implemented by calling sys_wait4() from libc.a. |
| 1656 | */ |
| 1657 | asmlinkage long sys_waitpid(pid_t pid, int __user *stat_addr, int options) |
| 1658 | { |
| 1659 | return sys_wait4(pid, stat_addr, options, NULL); |
| 1660 | } |
| 1661 | |
| 1662 | #endif |