diff options
Diffstat (limited to 'libdde_linux26/lib/src/kernel/exit.c')
| -rw-r--r-- | libdde_linux26/lib/src/kernel/exit.c | 1850 |
1 files changed, 0 insertions, 1850 deletions
diff --git a/libdde_linux26/lib/src/kernel/exit.c b/libdde_linux26/lib/src/kernel/exit.c deleted file mode 100644 index 703f9aab..00000000 --- a/libdde_linux26/lib/src/kernel/exit.c +++ /dev/null @@ -1,1850 +0,0 @@ -/* - * linux/kernel/exit.c - * - * Copyright (C) 1991, 1992 Linus Torvalds - */ - -#include <linux/mm.h> -#include <linux/slab.h> -#include <linux/interrupt.h> -#include <linux/module.h> -#include <linux/capability.h> -#include <linux/completion.h> -#include <linux/personality.h> -#include <linux/tty.h> -#include <linux/mnt_namespace.h> -#include <linux/iocontext.h> -#include <linux/key.h> -#include <linux/security.h> -#include <linux/cpu.h> -#include <linux/acct.h> -#include <linux/tsacct_kern.h> -#include <linux/file.h> -#include <linux/fdtable.h> -#include <linux/binfmts.h> -#include <linux/nsproxy.h> -#include <linux/pid_namespace.h> -#include <linux/ptrace.h> -#include <linux/profile.h> -#include <linux/mount.h> -#include <linux/proc_fs.h> -#include <linux/kthread.h> -#include <linux/mempolicy.h> -#include <linux/taskstats_kern.h> -#include <linux/delayacct.h> -#include <linux/freezer.h> -#include <linux/cgroup.h> -#include <linux/syscalls.h> -#include <linux/signal.h> -#include <linux/posix-timers.h> -#include <linux/cn_proc.h> -#include <linux/mutex.h> -#include <linux/futex.h> -#include <linux/pipe_fs_i.h> -#include <linux/audit.h> /* for audit_free() */ -#include <linux/resource.h> -#include <linux/blkdev.h> -#include <linux/task_io_accounting_ops.h> -#include <linux/tracehook.h> -#include <linux/init_task.h> -#include <trace/sched.h> - -#include <asm/uaccess.h> -#include <asm/unistd.h> -#include <asm/pgtable.h> -#include <asm/mmu_context.h> -#include "cred-internals.h" - -DEFINE_TRACE(sched_process_free); -DEFINE_TRACE(sched_process_exit); -DEFINE_TRACE(sched_process_wait); - -#ifndef DDE_LINUX -static void exit_mm(struct task_struct * tsk); - -static inline int task_detached(struct task_struct *p) -{ - return p->exit_signal == -1; -} - -static void __unhash_process(struct task_struct *p) -{ - nr_threads--; - detach_pid(p, PIDTYPE_PID); - if (thread_group_leader(p)) { - detach_pid(p, PIDTYPE_PGID); - detach_pid(p, PIDTYPE_SID); - - list_del_rcu(&p->tasks); - __get_cpu_var(process_counts)--; - } - list_del_rcu(&p->thread_group); - list_del_init(&p->sibling); -} - -/* - * This function expects the tasklist_lock write-locked. - */ -static void __exit_signal(struct task_struct *tsk) -{ - struct signal_struct *sig = tsk->signal; - struct sighand_struct *sighand; - - BUG_ON(!sig); - BUG_ON(!atomic_read(&sig->count)); - - sighand = rcu_dereference(tsk->sighand); - spin_lock(&sighand->siglock); - - posix_cpu_timers_exit(tsk); - if (atomic_dec_and_test(&sig->count)) - posix_cpu_timers_exit_group(tsk); - else { - /* - * If there is any task waiting for the group exit - * then notify it: - */ - if (sig->group_exit_task && atomic_read(&sig->count) == sig->notify_count) - wake_up_process(sig->group_exit_task); - - if (tsk == sig->curr_target) - sig->curr_target = next_thread(tsk); - /* - * Accumulate here the counters for all threads but the - * group leader as they die, so they can be added into - * the process-wide totals when those are taken. - * The group leader stays around as a zombie as long - * as there are other threads. When it gets reaped, - * the exit.c code will add its counts into these totals. - * We won't ever get here for the group leader, since it - * will have been the last reference on the signal_struct. - */ - sig->utime = cputime_add(sig->utime, task_utime(tsk)); - sig->stime = cputime_add(sig->stime, task_stime(tsk)); - sig->gtime = cputime_add(sig->gtime, task_gtime(tsk)); - sig->min_flt += tsk->min_flt; - sig->maj_flt += tsk->maj_flt; - sig->nvcsw += tsk->nvcsw; - sig->nivcsw += tsk->nivcsw; - sig->inblock += task_io_get_inblock(tsk); - sig->oublock += task_io_get_oublock(tsk); - task_io_accounting_add(&sig->ioac, &tsk->ioac); - sig->sum_sched_runtime += tsk->se.sum_exec_runtime; - sig = NULL; /* Marker for below. */ - } - - __unhash_process(tsk); - - /* - * Do this under ->siglock, we can race with another thread - * doing sigqueue_free() if we have SIGQUEUE_PREALLOC signals. - */ - flush_sigqueue(&tsk->pending); - - tsk->signal = NULL; - tsk->sighand = NULL; - spin_unlock(&sighand->siglock); - - __cleanup_sighand(sighand); - clear_tsk_thread_flag(tsk,TIF_SIGPENDING); - if (sig) { - flush_sigqueue(&sig->shared_pending); - taskstats_tgid_free(sig); - /* - * Make sure ->signal can't go away under rq->lock, - * see account_group_exec_runtime(). - */ - task_rq_unlock_wait(tsk); - __cleanup_signal(sig); - } -} - -static void delayed_put_task_struct(struct rcu_head *rhp) -{ - struct task_struct *tsk = container_of(rhp, struct task_struct, rcu); - - trace_sched_process_free(tsk); - put_task_struct(tsk); -} - - -void release_task(struct task_struct * p) -{ - struct task_struct *leader; - int zap_leader; -repeat: - tracehook_prepare_release_task(p); - /* don't need to get the RCU readlock here - the process is dead and - * can't be modifying its own credentials */ - atomic_dec(&__task_cred(p)->user->processes); - - proc_flush_task(p); - write_lock_irq(&tasklist_lock); - tracehook_finish_release_task(p); - __exit_signal(p); - - /* - * If we are the last non-leader member of the thread - * group, and the leader is zombie, then notify the - * group leader's parent process. (if it wants notification.) - */ - zap_leader = 0; - leader = p->group_leader; - if (leader != p && thread_group_empty(leader) && leader->exit_state == EXIT_ZOMBIE) { - BUG_ON(task_detached(leader)); - do_notify_parent(leader, leader->exit_signal); - /* - * If we were the last child thread and the leader has - * exited already, and the leader's parent ignores SIGCHLD, - * then we are the one who should release the leader. - * - * do_notify_parent() will have marked it self-reaping in - * that case. - */ - zap_leader = task_detached(leader); - - /* - * This maintains the invariant that release_task() - * only runs on a task in EXIT_DEAD, just for sanity. - */ - if (zap_leader) - leader->exit_state = EXIT_DEAD; - } - - write_unlock_irq(&tasklist_lock); - release_thread(p); - call_rcu(&p->rcu, delayed_put_task_struct); - - p = leader; - if (unlikely(zap_leader)) - goto repeat; -} - -/* - * This checks not only the pgrp, but falls back on the pid if no - * satisfactory pgrp is found. I dunno - gdb doesn't work correctly - * without this... - * - * The caller must hold rcu lock or the tasklist lock. - */ -struct pid *session_of_pgrp(struct pid *pgrp) -{ - struct task_struct *p; - struct pid *sid = NULL; - - p = pid_task(pgrp, PIDTYPE_PGID); - if (p == NULL) - p = pid_task(pgrp, PIDTYPE_PID); - if (p != NULL) - sid = task_session(p); - - return sid; -} - -/* - * Determine if a process group is "orphaned", according to the POSIX - * definition in 2.2.2.52. Orphaned process groups are not to be affected - * by terminal-generated stop signals. Newly orphaned process groups are - * to receive a SIGHUP and a SIGCONT. - * - * "I ask you, have you ever known what it is to be an orphan?" - */ -static int will_become_orphaned_pgrp(struct pid *pgrp, struct task_struct *ignored_task) -{ - struct task_struct *p; - - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { - if ((p == ignored_task) || - (p->exit_state && thread_group_empty(p)) || - is_global_init(p->real_parent)) - continue; - - if (task_pgrp(p->real_parent) != pgrp && - task_session(p->real_parent) == task_session(p)) - return 0; - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); - - return 1; -} - -int is_current_pgrp_orphaned(void) -{ - int retval; - - read_lock(&tasklist_lock); - retval = will_become_orphaned_pgrp(task_pgrp(current), NULL); - read_unlock(&tasklist_lock); - - return retval; -} - -static int has_stopped_jobs(struct pid *pgrp) -{ - int retval = 0; - struct task_struct *p; - - do_each_pid_task(pgrp, PIDTYPE_PGID, p) { - if (!task_is_stopped(p)) - continue; - retval = 1; - break; - } while_each_pid_task(pgrp, PIDTYPE_PGID, p); - return retval; -} - -/* - * Check to see if any process groups have become orphaned as - * a result of our exiting, and if they have any stopped jobs, - * send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) - */ -static void -kill_orphaned_pgrp(struct task_struct *tsk, struct task_struct *parent) -{ - struct pid *pgrp = task_pgrp(tsk); - struct task_struct *ignored_task = tsk; - - if (!parent) - /* exit: our father is in a different pgrp than - * we are and we were the only connection outside. - */ - parent = tsk->real_parent; - else - /* reparent: our child is in a different pgrp than - * we are, and it was the only connection outside. - */ - ignored_task = NULL; - - if (task_pgrp(parent) != pgrp && - task_session(parent) == task_session(tsk) && - will_become_orphaned_pgrp(pgrp, ignored_task) && - has_stopped_jobs(pgrp)) { - __kill_pgrp_info(SIGHUP, SEND_SIG_PRIV, pgrp); - __kill_pgrp_info(SIGCONT, SEND_SIG_PRIV, pgrp); - } -} - -/** - * reparent_to_kthreadd - Reparent the calling kernel thread to kthreadd - * - * If a kernel thread is launched as a result of a system call, or if - * it ever exits, it should generally reparent itself to kthreadd so it - * isn't in the way of other processes and is correctly cleaned up on exit. - * - * The various task state such as scheduling policy and priority may have - * been inherited from a user process, so we reset them to sane values here. - * - * NOTE that reparent_to_kthreadd() gives the caller full capabilities. - */ -static void reparent_to_kthreadd(void) -{ - write_lock_irq(&tasklist_lock); - - ptrace_unlink(current); - /* Reparent to init */ - current->real_parent = current->parent = kthreadd_task; - list_move_tail(¤t->sibling, ¤t->real_parent->children); - - /* Set the exit signal to SIGCHLD so we signal init on exit */ - current->exit_signal = SIGCHLD; - - if (task_nice(current) < 0) - set_user_nice(current, 0); - /* cpus_allowed? */ - /* rt_priority? */ - /* signals? */ - memcpy(current->signal->rlim, init_task.signal->rlim, - sizeof(current->signal->rlim)); - -#ifndef DDE_LINUX - atomic_inc(&init_cred.usage); - commit_creds(&init_cred); -#endif - write_unlock_irq(&tasklist_lock); -} - -void __set_special_pids(struct pid *pid) -{ - struct task_struct *curr = current->group_leader; - pid_t nr = pid_nr(pid); - - if (task_session(curr) != pid) { - change_pid(curr, PIDTYPE_SID, pid); - set_task_session(curr, nr); - } - if (task_pgrp(curr) != pid) { - change_pid(curr, PIDTYPE_PGID, pid); - set_task_pgrp(curr, nr); - } -} - -static void set_special_pids(struct pid *pid) -{ - write_lock_irq(&tasklist_lock); - __set_special_pids(pid); - write_unlock_irq(&tasklist_lock); -} - -/* - * Let kernel threads use this to say that they - * allow a certain signal (since daemonize() will - * have disabled all of them by default). - */ -int allow_signal(int sig) -{ - if (!valid_signal(sig) || sig < 1) - return -EINVAL; - - spin_lock_irq(¤t->sighand->siglock); - sigdelset(¤t->blocked, sig); - if (!current->mm) { - /* Kernel threads handle their own signals. - Let the signal code know it'll be handled, so - that they don't get converted to SIGKILL or - just silently dropped */ - current->sighand->action[(sig)-1].sa.sa_handler = (void __user *)2; - } - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - return 0; -} - -EXPORT_SYMBOL(allow_signal); - -int disallow_signal(int sig) -{ - if (!valid_signal(sig) || sig < 1) - return -EINVAL; - - spin_lock_irq(¤t->sighand->siglock); - current->sighand->action[(sig)-1].sa.sa_handler = SIG_IGN; - recalc_sigpending(); - spin_unlock_irq(¤t->sighand->siglock); - return 0; -} - -EXPORT_SYMBOL(disallow_signal); - -/* - * Put all the gunge required to become a kernel thread without - * attached user resources in one place where it belongs. - */ - -void daemonize(const char *name, ...) -{ - va_list args; - struct fs_struct *fs; - sigset_t blocked; - - va_start(args, name); - vsnprintf(current->comm, sizeof(current->comm), name, args); - va_end(args); - - /* - * If we were started as result of loading a module, close all of the - * user space pages. We don't need them, and if we didn't close them - * they would be locked into memory. - */ - exit_mm(current); - /* - * We don't want to have TIF_FREEZE set if the system-wide hibernation - * or suspend transition begins right now. - */ - current->flags |= (PF_NOFREEZE | PF_KTHREAD); - - if (current->nsproxy != &init_nsproxy) { - get_nsproxy(&init_nsproxy); - switch_task_namespaces(current, &init_nsproxy); - } - set_special_pids(&init_struct_pid); - proc_clear_tty(current); - - /* Block and flush all signals */ - sigfillset(&blocked); - sigprocmask(SIG_BLOCK, &blocked, NULL); - flush_signals(current); - - /* Become as one with the init task */ - - exit_fs(current); /* current->fs->count--; */ - fs = init_task.fs; - current->fs = fs; - atomic_inc(&fs->count); - - exit_files(current); - current->files = init_task.files; - atomic_inc(¤t->files->count); - - reparent_to_kthreadd(); -} - -EXPORT_SYMBOL(daemonize); - -static void close_files(struct files_struct * files) -{ - int i, j; - struct fdtable *fdt; - - j = 0; - - /* - * It is safe to dereference the fd table without RCU or - * ->file_lock because this is the last reference to the - * files structure. - */ - fdt = files_fdtable(files); - for (;;) { - unsigned long set; - i = j * __NFDBITS; - if (i >= fdt->max_fds) - break; - set = fdt->open_fds->fds_bits[j++]; - while (set) { - if (set & 1) { - struct file * file = xchg(&fdt->fd[i], NULL); - if (file) { - filp_close(file, files); - cond_resched(); - } - } - i++; - set >>= 1; - } - } -} - -struct files_struct *get_files_struct(struct task_struct *task) -{ - struct files_struct *files; - - task_lock(task); - files = task->files; - if (files) - atomic_inc(&files->count); - task_unlock(task); - - return files; -} - -void put_files_struct(struct files_struct *files) -{ - struct fdtable *fdt; - - if (atomic_dec_and_test(&files->count)) { - close_files(files); - /* - * Free the fd and fdset arrays if we expanded them. - * If the fdtable was embedded, pass files for freeing - * at the end of the RCU grace period. Otherwise, - * you can free files immediately. - */ - fdt = files_fdtable(files); - if (fdt != &files->fdtab) - kmem_cache_free(files_cachep, files); - free_fdtable(fdt); - } -} - -void reset_files_struct(struct files_struct *files) -{ - struct task_struct *tsk = current; - struct files_struct *old; - - old = tsk->files; - task_lock(tsk); - tsk->files = files; - task_unlock(tsk); - put_files_struct(old); -} - -void exit_files(struct task_struct *tsk) -{ - struct files_struct * files = tsk->files; - - if (files) { - task_lock(tsk); - tsk->files = NULL; - task_unlock(tsk); - put_files_struct(files); - } -} - -void put_fs_struct(struct fs_struct *fs) -{ - /* No need to hold fs->lock if we are killing it */ - if (atomic_dec_and_test(&fs->count)) { - path_put(&fs->root); - path_put(&fs->pwd); - kmem_cache_free(fs_cachep, fs); - } -} - -void exit_fs(struct task_struct *tsk) -{ - struct fs_struct * fs = tsk->fs; - - if (fs) { - task_lock(tsk); - tsk->fs = NULL; - task_unlock(tsk); - put_fs_struct(fs); - } -} - -EXPORT_SYMBOL_GPL(exit_fs); - -#ifdef CONFIG_MM_OWNER -/* - * Task p is exiting and it owned mm, lets find a new owner for it - */ -static inline int -mm_need_new_owner(struct mm_struct *mm, struct task_struct *p) -{ - /* - * If there are other users of the mm and the owner (us) is exiting - * we need to find a new owner to take on the responsibility. - */ - if (atomic_read(&mm->mm_users) <= 1) - return 0; - if (mm->owner != p) - return 0; - return 1; -} - -void mm_update_next_owner(struct mm_struct *mm) -{ - struct task_struct *c, *g, *p = current; - -retry: - if (!mm_need_new_owner(mm, p)) - return; - - read_lock(&tasklist_lock); - /* - * Search in the children - */ - list_for_each_entry(c, &p->children, sibling) { - if (c->mm == mm) - goto assign_new_owner; - } - - /* - * Search in the siblings - */ - list_for_each_entry(c, &p->parent->children, sibling) { - if (c->mm == mm) - goto assign_new_owner; - } - - /* - * Search through everything else. We should not get - * here often - */ - do_each_thread(g, c) { - if (c->mm == mm) - goto assign_new_owner; - } while_each_thread(g, c); - - read_unlock(&tasklist_lock); - /* - * We found no owner yet mm_users > 1: this implies that we are - * most likely racing with swapoff (try_to_unuse()) or /proc or - * ptrace or page migration (get_task_mm()). Mark owner as NULL. - */ - mm->owner = NULL; - return; - -assign_new_owner: - BUG_ON(c == p); - get_task_struct(c); - /* - * The task_lock protects c->mm from changing. - * We always want mm->owner->mm == mm - */ - task_lock(c); - /* - * Delay read_unlock() till we have the task_lock() - * to ensure that c does not slip away underneath us - */ - read_unlock(&tasklist_lock); - if (c->mm != mm) { - task_unlock(c); - put_task_struct(c); - goto retry; - } - mm->owner = c; - task_unlock(c); - put_task_struct(c); -} -#endif /* CONFIG_MM_OWNER */ - -/* - * Turn us into a lazy TLB process if we - * aren't already.. - */ -static void exit_mm(struct task_struct * tsk) -{ - struct mm_struct *mm = tsk->mm; - struct core_state *core_state; - - mm_release(tsk, mm); - if (!mm) - return; - /* - * Serialize with any possible pending coredump. - * We must hold mmap_sem around checking core_state - * and clearing tsk->mm. The core-inducing thread - * will increment ->nr_threads for each thread in the - * group with ->mm != NULL. - */ - down_read(&mm->mmap_sem); - core_state = mm->core_state; - if (core_state) { - struct core_thread self; - up_read(&mm->mmap_sem); - - self.task = tsk; - self.next = xchg(&core_state->dumper.next, &self); - /* - * Implies mb(), the result of xchg() must be visible - * to core_state->dumper. - */ - if (atomic_dec_and_test(&core_state->nr_threads)) - complete(&core_state->startup); - - for (;;) { - set_task_state(tsk, TASK_UNINTERRUPTIBLE); - if (!self.task) /* see coredump_finish() */ - break; - schedule(); - } - __set_task_state(tsk, TASK_RUNNING); - down_read(&mm->mmap_sem); - } - atomic_inc(&mm->mm_count); - BUG_ON(mm != tsk->active_mm); - /* more a memory barrier than a real lock */ - task_lock(tsk); - tsk->mm = NULL; - up_read(&mm->mmap_sem); - enter_lazy_tlb(mm, current); - /* We don't want this task to be frozen prematurely */ - clear_freeze_flag(tsk); - task_unlock(tsk); - mm_update_next_owner(mm); - mmput(mm); -} - -/* - * Return nonzero if @parent's children should reap themselves. - * - * Called with write_lock_irq(&tasklist_lock) held. - */ -static int ignoring_children(struct task_struct *parent) -{ - int ret; - struct sighand_struct *psig = parent->sighand; - unsigned long flags; - spin_lock_irqsave(&psig->siglock, flags); - ret = (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN || - (psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT)); - spin_unlock_irqrestore(&psig->siglock, flags); - return ret; -} - -/* - * Detach all tasks we were using ptrace on. - * Any that need to be release_task'd are put on the @dead list. - * - * Called with write_lock(&tasklist_lock) held. - */ -static void ptrace_exit(struct task_struct *parent, struct list_head *dead) -{ - struct task_struct *p, *n; - int ign = -1; - - list_for_each_entry_safe(p, n, &parent->ptraced, ptrace_entry) { - __ptrace_unlink(p); - - if (p->exit_state != EXIT_ZOMBIE) - continue; - - /* - * If it's a zombie, our attachedness prevented normal - * parent notification or self-reaping. Do notification - * now if it would have happened earlier. If it should - * reap itself, add it to the @dead list. We can't call - * release_task() here because we already hold tasklist_lock. - * - * If it's our own child, there is no notification to do. - * But if our normal children self-reap, then this child - * was prevented by ptrace and we must reap it now. - */ - if (!task_detached(p) && thread_group_empty(p)) { - if (!same_thread_group(p->real_parent, parent)) - do_notify_parent(p, p->exit_signal); - else { - if (ign < 0) - ign = ignoring_children(parent); - if (ign) - p->exit_signal = -1; - } - } - - if (task_detached(p)) { - /* - * Mark it as in the process of being reaped. - */ - p->exit_state = EXIT_DEAD; - list_add(&p->ptrace_entry, dead); - } - } -} - -/* - * Finish up exit-time ptrace cleanup. - * - * Called without locks. - */ -static void ptrace_exit_finish(struct task_struct *parent, - struct list_head *dead) -{ - struct task_struct *p, *n; - - BUG_ON(!list_empty(&parent->ptraced)); - - list_for_each_entry_safe(p, n, dead, ptrace_entry) { - list_del_init(&p->ptrace_entry); - release_task(p); - } -} - -static void reparent_thread(struct task_struct *p, struct task_struct *father) -{ - if (p->pdeath_signal) - /* We already hold the tasklist_lock here. */ - group_send_sig_info(p->pdeath_signal, SEND_SIG_NOINFO, p); - - list_move_tail(&p->sibling, &p->real_parent->children); - - /* If this is a threaded reparent there is no need to - * notify anyone anything has happened. - */ - if (same_thread_group(p->real_parent, father)) - return; - - /* We don't want people slaying init. */ - if (!task_detached(p)) - p->exit_signal = SIGCHLD; - - /* If we'd notified the old parent about this child's death, - * also notify the new parent. - */ - if (!ptrace_reparented(p) && - p->exit_state == EXIT_ZOMBIE && - !task_detached(p) && thread_group_empty(p)) - do_notify_parent(p, p->exit_signal); - - kill_orphaned_pgrp(p, father); -} - -/* - * When we die, we re-parent all our children. - * Try to give them to another thread in our thread - * group, and if no such member exists, give it to - * the child reaper process (ie "init") in our pid - * space. - */ -static struct task_struct *find_new_reaper(struct task_struct *father) -{ - struct pid_namespace *pid_ns = task_active_pid_ns(father); - struct task_struct *thread; - - thread = father; - while_each_thread(father, thread) { - if (thread->flags & PF_EXITING) - continue; - if (unlikely(pid_ns->child_reaper == father)) - pid_ns->child_reaper = thread; - return thread; - } - - if (unlikely(pid_ns->child_reaper == father)) { - write_unlock_irq(&tasklist_lock); - if (unlikely(pid_ns == &init_pid_ns)) - panic("Attempted to kill init!"); - - zap_pid_ns_processes(pid_ns); - write_lock_irq(&tasklist_lock); - /* - * We can not clear ->child_reaper or leave it alone. - * There may by stealth EXIT_DEAD tasks on ->children, - * forget_original_parent() must move them somewhere. - */ - pid_ns->child_reaper = init_pid_ns.child_reaper; - } - - return pid_ns->child_reaper; -} - -static void forget_original_parent(struct task_struct *father) -{ - struct task_struct *p, *n, *reaper; - LIST_HEAD(ptrace_dead); - - write_lock_irq(&tasklist_lock); - reaper = find_new_reaper(father); - /* - * First clean up ptrace if we were using it. - */ - ptrace_exit(father, &ptrace_dead); - - list_for_each_entry_safe(p, n, &father->children, sibling) { - p->real_parent = reaper; - if (p->parent == father) { - BUG_ON(p->ptrace); - p->parent = p->real_parent; - } - reparent_thread(p, father); - } - - write_unlock_irq(&tasklist_lock); - BUG_ON(!list_empty(&father->children)); - - ptrace_exit_finish(father, &ptrace_dead); -} - -/* - * Send signals to all our closest relatives so that they know - * to properly mourn us.. - */ -static void exit_notify(struct task_struct *tsk, int group_dead) -{ - int signal; - void *cookie; - - /* - * This does two things: - * - * A. Make init inherit all the child processes - * B. Check to see if any process groups have become orphaned - * as a result of our exiting, and if they have any stopped - * jobs, send them a SIGHUP and then a SIGCONT. (POSIX 3.2.2.2) - */ - forget_original_parent(tsk); - exit_task_namespaces(tsk); - - write_lock_irq(&tasklist_lock); - if (group_dead) - kill_orphaned_pgrp(tsk->group_leader, NULL); - - /* Let father know we died - * - * Thread signals are configurable, but you aren't going to use - * that to send signals to arbitary processes. - * That stops right now. - * - * If the parent exec id doesn't match the exec id we saved - * when we started then we know the parent has changed security - * domain. - * - * If our self_exec id doesn't match our parent_exec_id then - * we have changed execution domain as these two values started - * the same after a fork. - */ - if (tsk->exit_signal != SIGCHLD && !task_detached(tsk) && - (tsk->parent_exec_id != tsk->real_parent->self_exec_id || - tsk->self_exec_id != tsk->parent_exec_id) && - !capable(CAP_KILL)) - tsk->exit_signal = SIGCHLD; - - signal = tracehook_notify_death(tsk, &cookie, group_dead); - if (signal >= 0) - signal = do_notify_parent(tsk, signal); - - tsk->exit_state = signal == DEATH_REAP ? EXIT_DEAD : EXIT_ZOMBIE; - - /* mt-exec, de_thread() is waiting for us */ - if (thread_group_leader(tsk) && - tsk->signal->group_exit_task && - tsk->signal->notify_count < 0) - wake_up_process(tsk->signal->group_exit_task); - - write_unlock_irq(&tasklist_lock); - - tracehook_report_death(tsk, signal, cookie, group_dead); - - /* If the process is dead, release it - nobody will wait for it */ - if (signal == DEATH_REAP) - release_task(tsk); -} - -#ifdef CONFIG_DEBUG_STACK_USAGE -static void check_stack_usage(void) -{ - static DEFINE_SPINLOCK(low_water_lock); - static int lowest_to_date = THREAD_SIZE; - unsigned long *n = end_of_stack(current); - unsigned long free; - - while (*n == 0) - n++; - free = (unsigned long)n - (unsigned long)end_of_stack(current); - - if (free >= lowest_to_date) - return; - - spin_lock(&low_water_lock); - if (free < lowest_to_date) { - printk(KERN_WARNING "%s used greatest stack depth: %lu bytes " - "left\n", - current->comm, free); - lowest_to_date = free; - } - spin_unlock(&low_water_lock); -} -#else -static inline void check_stack_usage(void) {} -#endif - -NORET_TYPE void do_exit(long code) -{ - struct task_struct *tsk = current; - int group_dead; - - profile_task_exit(tsk); - - WARN_ON(atomic_read(&tsk->fs_excl)); - - if (unlikely(in_interrupt())) - panic("Aiee, killing interrupt handler!"); - if (unlikely(!tsk->pid)) - panic("Attempted to kill the idle task!"); - - tracehook_report_exit(&code); - - /* - * We're taking recursive faults here in do_exit. Safest is to just - * leave this task alone and wait for reboot. - */ - if (unlikely(tsk->flags & PF_EXITING)) { - printk(KERN_ALERT - "Fixing recursive fault but reboot is needed!\n"); - /* - * We can do this unlocked here. The futex code uses - * this flag just to verify whether the pi state - * cleanup has been done or not. In the worst case it - * loops once more. We pretend that the cleanup was - * done as there is no way to return. Either the - * OWNER_DIED bit is set by now or we push the blocked - * task into the wait for ever nirwana as well. - */ - tsk->flags |= PF_EXITPIDONE; - set_current_state(TASK_UNINTERRUPTIBLE); - schedule(); - } - - exit_signals(tsk); /* sets PF_EXITING */ - /* - * tsk->flags are checked in the futex code to protect against - * an exiting task cleaning up the robust pi futexes. - */ - smp_mb(); - spin_unlock_wait(&tsk->pi_lock); - - if (unlikely(in_atomic())) - printk(KERN_INFO "note: %s[%d] exited with preempt_count %d\n", - current->comm, task_pid_nr(current), - preempt_count()); - - acct_update_integrals(tsk); - - group_dead = atomic_dec_and_test(&tsk->signal->live); - if (group_dead) { - hrtimer_cancel(&tsk->signal->real_timer); - exit_itimers(tsk->signal); - } - acct_collect(code, group_dead); - if (group_dead) - tty_audit_exit(); - if (unlikely(tsk->audit_context)) - audit_free(tsk); - - tsk->exit_code = code; - taskstats_exit(tsk, group_dead); - - exit_mm(tsk); - - if (group_dead) - acct_process(); - trace_sched_process_exit(tsk); - - exit_sem(tsk); - exit_files(tsk); - exit_fs(tsk); - check_stack_usage(); - exit_thread(); - cgroup_exit(tsk, 1); - - if (group_dead && tsk->signal->leader) - disassociate_ctty(1); - - module_put(task_thread_info(tsk)->exec_domain->module); - if (tsk->binfmt) - module_put(tsk->binfmt->module); - - proc_exit_connector(tsk); - exit_notify(tsk, group_dead); -#ifdef CONFIG_NUMA - mpol_put(tsk->mempolicy); - tsk->mempolicy = NULL; -#endif -#ifdef CONFIG_FUTEX - /* - * This must happen late, after the PID is not - * hashed anymore: - */ - if (unlikely(!list_empty(&tsk->pi_state_list))) - exit_pi_state_list(tsk); - if (unlikely(current->pi_state_cache)) - kfree(current->pi_state_cache); -#endif - /* - * Make sure we are holding no locks: - */ - debug_check_no_locks_held(tsk); - /* - * We can do this unlocked here. The futex code uses this flag - * just to verify whether the pi state cleanup has been done - * or not. In the worst case it loops once more. - */ - tsk->flags |= PF_EXITPIDONE; - - if (tsk->io_context) - exit_io_context(); - - if (tsk->splice_pipe) - __free_pipe_info(tsk->splice_pipe); - - preempt_disable(); - /* causes final put_task_struct in finish_task_switch(). */ - tsk->state = TASK_DEAD; - schedule(); - BUG(); - /* Avoid "noreturn function does return". */ - for (;;) - cpu_relax(); /* For when BUG is null */ -} - -EXPORT_SYMBOL_GPL(do_exit); - -#endif /* !DDE_LINUX */ - -NORET_TYPE void complete_and_exit(struct completion *comp, long code) -{ - if (comp) - complete(comp); - - do_exit(code); -} - -EXPORT_SYMBOL(complete_and_exit); - -#ifndef DDE_LINUX -SYSCALL_DEFINE1(exit, int, error_code) -{ - do_exit((error_code&0xff)<<8); -} - -/* - * Take down every thread in the group. This is called by fatal signals - * as well as by sys_exit_group (below). - */ -NORET_TYPE void -do_group_exit(int exit_code) -{ - struct signal_struct *sig = current->signal; - - BUG_ON(exit_code & 0x80); /* core dumps don't get here */ - - if (signal_group_exit(sig)) - exit_code = sig->group_exit_code; - else if (!thread_group_empty(current)) { - struct sighand_struct *const sighand = current->sighand; - spin_lock_irq(&sighand->siglock); - if (signal_group_exit(sig)) - /* Another thread got here before we took the lock. */ - exit_code = sig->group_exit_code; - else { - sig->group_exit_code = exit_code; - sig->flags = SIGNAL_GROUP_EXIT; - zap_other_threads(current); - } - spin_unlock_irq(&sighand->siglock); - } - - do_exit(exit_code); - /* NOTREACHED */ -} - -/* - * this kills every thread in the thread group. Note that any externally - * wait4()-ing process will get the correct exit code - even if this - * thread is not the thread group leader. - */ -SYSCALL_DEFINE1(exit_group, int, error_code) -{ - do_group_exit((error_code & 0xff) << 8); - /* NOTREACHED */ - return 0; -} - -static struct pid *task_pid_type(struct task_struct *task, enum pid_type type) -{ - struct pid *pid = NULL; - if (type == PIDTYPE_PID) - pid = task->pids[type].pid; - else if (type < PIDTYPE_MAX) - pid = task->group_leader->pids[type].pid; - return pid; -} - -static int eligible_child(enum pid_type type, struct pid *pid, int options, - struct task_struct *p) -{ - int err; - - if (type < PIDTYPE_MAX) { - if (task_pid_type(p, type) != pid) - return 0; - } - - /* Wait for all children (clone and not) if __WALL is set; - * otherwise, wait for clone children *only* if __WCLONE is - * set; otherwise, wait for non-clone children *only*. (Note: - * A "clone" child here is one that reports to its parent - * using a signal other than SIGCHLD.) */ - if (((p->exit_signal != SIGCHLD) ^ ((options & __WCLONE) != 0)) - && !(options & __WALL)) - return 0; - - err = security_task_wait(p); - if (err) - return err; - - return 1; -} - -static int wait_noreap_copyout(struct task_struct *p, pid_t pid, uid_t uid, - int why, int status, - struct siginfo __user *infop, - struct rusage __user *rusagep) -{ - int retval = rusagep ? getrusage(p, RUSAGE_BOTH, rusagep) : 0; - - put_task_struct(p); - if (!retval) - retval = put_user(SIGCHLD, &infop->si_signo); - if (!retval) - retval = put_user(0, &infop->si_errno); - if (!retval) - retval = put_user((short)why, &infop->si_code); - if (!retval) - retval = put_user(pid, &infop->si_pid); - if (!retval) - retval = put_user(uid, &infop->si_uid); - if (!retval) - retval = put_user(status, &infop->si_status); - if (!retval) - retval = pid; - return retval; -} - -/* - * Handle sys_wait4 work for one task in state EXIT_ZOMBIE. We hold - * read_lock(&tasklist_lock) on entry. If we return zero, we still hold - * the lock and this task is uninteresting. If we return nonzero, we have - * released the lock and the system call should return. - */ -static int wait_task_zombie(struct task_struct *p, int options, - struct siginfo __user *infop, - int __user *stat_addr, struct rusage __user *ru) -{ - unsigned long state; - int retval, status, traced; - pid_t pid = task_pid_vnr(p); - uid_t uid = __task_cred(p)->uid; - - if (!likely(options & WEXITED)) - return 0; - - if (unlikely(options & WNOWAIT)) { - int exit_code = p->exit_code; - int why, status; - - get_task_struct(p); - read_unlock(&tasklist_lock); - if ((exit_code & 0x7f) == 0) { - why = CLD_EXITED; - status = exit_code >> 8; - } else { - why = (exit_code & 0x80) ? CLD_DUMPED : CLD_KILLED; - status = exit_code & 0x7f; - } - return wait_noreap_copyout(p, pid, uid, why, - status, infop, ru); - } - - /* - * Try to move the task's state to DEAD - * only one thread is allowed to do this: - */ - state = xchg(&p->exit_state, EXIT_DEAD); - if (state != EXIT_ZOMBIE) { - BUG_ON(state != EXIT_DEAD); - return 0; - } - - traced = ptrace_reparented(p); - - if (likely(!traced)) { - struct signal_struct *psig; - struct signal_struct *sig; - struct task_cputime cputime; - - /* - * The resource counters for the group leader are in its - * own task_struct. Those for dead threads in the group - * are in its signal_struct, as are those for the child - * processes it has previously reaped. All these - * accumulate in the parent's signal_struct c* fields. - * - * We don't bother to take a lock here to protect these - * p->signal fields, because they are only touched by - * __exit_signal, which runs with tasklist_lock - * write-locked anyway, and so is excluded here. We do - * need to protect the access to p->parent->signal fields, - * as other threads in the parent group can be right - * here reaping other children at the same time. - * - * We use thread_group_cputime() to get times for the thread - * group, which consolidates times for all threads in the - * group including the group leader. - */ - thread_group_cputime(p, &cputime); - spin_lock_irq(&p->parent->sighand->siglock); - psig = p->parent->signal; - sig = p->signal; - psig->cutime = - cputime_add(psig->cutime, - cputime_add(cputime.utime, - sig->cutime)); - psig->cstime = - cputime_add(psig->cstime, - cputime_add(cputime.stime, - sig->cstime)); - psig->cgtime = - cputime_add(psig->cgtime, - cputime_add(p->gtime, - cputime_add(sig->gtime, - sig->cgtime))); - psig->cmin_flt += - p->min_flt + sig->min_flt + sig->cmin_flt; - psig->cmaj_flt += - p->maj_flt + sig->maj_flt + sig->cmaj_flt; - psig->cnvcsw += - p->nvcsw + sig->nvcsw + sig->cnvcsw; - psig->cnivcsw += - p->nivcsw + sig->nivcsw + sig->cnivcsw; - psig->cinblock += - task_io_get_inblock(p) + - sig->inblock + sig->cinblock; - psig->coublock += - task_io_get_oublock(p) + - sig->oublock + sig->coublock; - task_io_accounting_add(&psig->ioac, &p->ioac); - task_io_accounting_add(&psig->ioac, &sig->ioac); - spin_unlock_irq(&p->parent->sighand->siglock); - } - - /* - * Now we are sure this task is interesting, and no other - * thread can reap it because we set its state to EXIT_DEAD. - */ - read_unlock(&tasklist_lock); - - retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; - status = (p->signal->flags & SIGNAL_GROUP_EXIT) - ? p->signal->group_exit_code : p->exit_code; - if (!retval && stat_addr) - retval = put_user(status, stat_addr); - if (!retval && infop) - retval = put_user(SIGCHLD, &infop->si_signo); - if (!retval && infop) - retval = put_user(0, &infop->si_errno); - if (!retval && infop) { - int why; - - if ((status & 0x7f) == 0) { - why = CLD_EXITED; - status >>= 8; - } else { - why = (status & 0x80) ? CLD_DUMPED : CLD_KILLED; - status &= 0x7f; - } - retval = put_user((short)why, &infop->si_code); - if (!retval) - retval = put_user(status, &infop->si_status); - } - if (!retval && infop) - retval = put_user(pid, &infop->si_pid); - if (!retval && infop) - retval = put_user(uid, &infop->si_uid); - if (!retval) - retval = pid; - - if (traced) { - write_lock_irq(&tasklist_lock); - /* We dropped tasklist, ptracer could die and untrace */ - ptrace_unlink(p); - /* - * If this is not a detached task, notify the parent. - * If it's still not detached after that, don't release - * it now. - */ - if (!task_detached(p)) { - do_notify_parent(p, p->exit_signal); - if (!task_detached(p)) { - p->exit_state = EXIT_ZOMBIE; - p = NULL; - } - } - write_unlock_irq(&tasklist_lock); - } - if (p != NULL) - release_task(p); - - return retval; -} - -/* - * Handle sys_wait4 work for one task in state TASK_STOPPED. We hold - * read_lock(&tasklist_lock) on entry. If we return zero, we still hold - * the lock and this task is uninteresting. If we return nonzero, we have - * released the lock and the system call should return. - */ -static int wait_task_stopped(int ptrace, struct task_struct *p, - int options, struct siginfo __user *infop, - int __user *stat_addr, struct rusage __user *ru) -{ - int retval, exit_code, why; - uid_t uid = 0; /* unneeded, required by compiler */ - pid_t pid; - - if (!(options & WUNTRACED)) - return 0; - - exit_code = 0; - spin_lock_irq(&p->sighand->siglock); - - if (unlikely(!task_is_stopped_or_traced(p))) - goto unlock_sig; - - if (!ptrace && p->signal->group_stop_count > 0) - /* - * A group stop is in progress and this is the group leader. - * We won't report until all threads have stopped. - */ - goto unlock_sig; - - exit_code = p->exit_code; - if (!exit_code) - goto unlock_sig; - - if (!unlikely(options & WNOWAIT)) - p->exit_code = 0; - - /* don't need the RCU readlock here as we're holding a spinlock */ - uid = __task_cred(p)->uid; -unlock_sig: - spin_unlock_irq(&p->sighand->siglock); - if (!exit_code) - return 0; - - /* - * Now we are pretty sure this task is interesting. - * Make sure it doesn't get reaped out from under us while we - * give up the lock and then examine it below. We don't want to - * keep holding onto the tasklist_lock while we call getrusage and - * possibly take page faults for user memory. - */ - get_task_struct(p); - pid = task_pid_vnr(p); - why = ptrace ? CLD_TRAPPED : CLD_STOPPED; - read_unlock(&tasklist_lock); - - if (unlikely(options & WNOWAIT)) - return wait_noreap_copyout(p, pid, uid, - why, exit_code, - infop, ru); - - retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; - if (!retval && stat_addr) - retval = put_user((exit_code << 8) | 0x7f, stat_addr); - if (!retval && infop) - retval = put_user(SIGCHLD, &infop->si_signo); - if (!retval && infop) - retval = put_user(0, &infop->si_errno); - if (!retval && infop) - retval = put_user((short)why, &infop->si_code); - if (!retval && infop) - retval = put_user(exit_code, &infop->si_status); - if (!retval && infop) - retval = put_user(pid, &infop->si_pid); - if (!retval && infop) - retval = put_user(uid, &infop->si_uid); - if (!retval) - retval = pid; - put_task_struct(p); - - BUG_ON(!retval); - return retval; -} - -/* - * Handle do_wait work for one task in a live, non-stopped state. - * read_lock(&tasklist_lock) on entry. If we return zero, we still hold - * the lock and this task is uninteresting. If we return nonzero, we have - * released the lock and the system call should return. - */ -static int wait_task_continued(struct task_struct *p, int options, - struct siginfo __user *infop, - int __user *stat_addr, struct rusage __user *ru) -{ - int retval; - pid_t pid; - uid_t uid; - - if (!unlikely(options & WCONTINUED)) - return 0; - - if (!(p->signal->flags & SIGNAL_STOP_CONTINUED)) - return 0; - - spin_lock_irq(&p->sighand->siglock); - /* Re-check with the lock held. */ - if (!(p->signal->flags & SIGNAL_STOP_CONTINUED)) { - spin_unlock_irq(&p->sighand->siglock); - return 0; - } - if (!unlikely(options & WNOWAIT)) - p->signal->flags &= ~SIGNAL_STOP_CONTINUED; - uid = __task_cred(p)->uid; - spin_unlock_irq(&p->sighand->siglock); - - pid = task_pid_vnr(p); - get_task_struct(p); - read_unlock(&tasklist_lock); - - if (!infop) { - retval = ru ? getrusage(p, RUSAGE_BOTH, ru) : 0; - put_task_struct(p); - if (!retval && stat_addr) - retval = put_user(0xffff, stat_addr); - if (!retval) - retval = pid; - } else { - retval = wait_noreap_copyout(p, pid, uid, - CLD_CONTINUED, SIGCONT, - infop, ru); - BUG_ON(retval == 0); - } - - return retval; -} - -/* - * Consider @p for a wait by @parent. - * - * -ECHILD should be in *@notask_error before the first call. - * Returns nonzero for a final return, when we have unlocked tasklist_lock. - * Returns zero if the search for a child should continue; - * then *@notask_error is 0 if @p is an eligible child, - * or another error from security_task_wait(), or still -ECHILD. - */ -static int wait_consider_task(struct task_struct *parent, int ptrace, - struct task_struct *p, int *notask_error, - enum pid_type type, struct pid *pid, int options, - struct siginfo __user *infop, - int __user *stat_addr, struct rusage __user *ru) -{ - int ret = eligible_child(type, pid, options, p); - if (!ret) - return ret; - - if (unlikely(ret < 0)) { - /* - * If we have not yet seen any eligible child, - * then let this error code replace -ECHILD. - * A permission error will give the user a clue - * to look for security policy problems, rather - * than for mysterious wait bugs. - */ - if (*notask_error) - *notask_error = ret; - } - - if (likely(!ptrace) && unlikely(p->ptrace)) { - /* - * This child is hidden by ptrace. - * We aren't allowed to see it now, but eventually we will. - */ - *notask_error = 0; - return 0; - } - - if (p->exit_state == EXIT_DEAD) - return 0; - - /* - * We don't reap group leaders with subthreads. - */ - if (p->exit_state == EXIT_ZOMBIE && !delay_group_leader(p)) - return wait_task_zombie(p, options, infop, stat_addr, ru); - - /* - * It's stopped or running now, so it might - * later continue, exit, or stop again. - */ - *notask_error = 0; - - if (task_is_stopped_or_traced(p)) - return wait_task_stopped(ptrace, p, options, - infop, stat_addr, ru); - - return wait_task_continued(p, options, infop, stat_addr, ru); -} - -/* - * Do the work of do_wait() for one thread in the group, @tsk. - * - * -ECHILD should be in *@notask_error before the first call. - * Returns nonzero for a final return, when we have unlocked tasklist_lock. - * Returns zero if the search for a child should continue; then - * *@notask_error is 0 if there were any eligible children, - * or another error from security_task_wait(), or still -ECHILD. - */ -static int do_wait_thread(struct task_struct *tsk, int *notask_error, - enum pid_type type, struct pid *pid, int options, - struct siginfo __user *infop, int __user *stat_addr, - struct rusage __user *ru) -{ - struct task_struct *p; - - list_for_each_entry(p, &tsk->children, sibling) { - /* - * Do not consider detached threads. - */ - if (!task_detached(p)) { - int ret = wait_consider_task(tsk, 0, p, notask_error, - type, pid, options, - infop, stat_addr, ru); - if (ret) - return ret; - } - } - - return 0; -} - -static int ptrace_do_wait(struct task_struct *tsk, int *notask_error, - enum pid_type type, struct pid *pid, int options, - struct siginfo __user *infop, int __user *stat_addr, - struct rusage __user *ru) -{ - struct task_struct *p; - - /* - * Traditionally we see ptrace'd stopped tasks regardless of options. - */ - options |= WUNTRACED; - - list_for_each_entry(p, &tsk->ptraced, ptrace_entry) { - int ret = wait_consider_task(tsk, 1, p, notask_error, - type, pid, options, - infop, stat_addr, ru); - if (ret) - return ret; - } - - return 0; -} - -static long do_wait(enum pid_type type, struct pid *pid, int options, - struct siginfo __user *infop, int __user *stat_addr, - struct rusage __user *ru) -{ - DECLARE_WAITQUEUE(wait, current); - struct task_struct *tsk; - int retval; - - trace_sched_process_wait(pid); - - add_wait_queue(¤t->signal->wait_chldexit,&wait); -repeat: - /* - * If there is nothing that can match our critiera just get out. - * We will clear @retval to zero if we see any child that might later - * match our criteria, even if we are not able to reap it yet. - */ - retval = -ECHILD; - if ((type < PIDTYPE_MAX) && (!pid || hlist_empty(&pid->tasks[type]))) - goto end; - - current->state = TASK_INTERRUPTIBLE; - read_lock(&tasklist_lock); - tsk = current; - do { - int tsk_result = do_wait_thread(tsk, &retval, - type, pid, options, - infop, stat_addr, ru); - if (!tsk_result) - tsk_result = ptrace_do_wait(tsk, &retval, - type, pid, options, - infop, stat_addr, ru); - if (tsk_result) { - /* - * tasklist_lock is unlocked and we have a final result. - */ - retval = tsk_result; - goto end; - } - - if (options & __WNOTHREAD) - break; - tsk = next_thread(tsk); - BUG_ON(tsk->signal != current->signal); - } while (tsk != current); - read_unlock(&tasklist_lock); - - if (!retval && !(options & WNOHANG)) { - retval = -ERESTARTSYS; - if (!signal_pending(current)) { - schedule(); - goto repeat; - } - } - -end: - current->state = TASK_RUNNING; - remove_wait_queue(¤t->signal->wait_chldexit,&wait); - if (infop) { - if (retval > 0) - retval = 0; - else { - /* - * For a WNOHANG return, clear out all the fields - * we would set so the user can easily tell the - * difference. - */ - if (!retval) - retval = put_user(0, &infop->si_signo); - if (!retval) - retval = put_user(0, &infop->si_errno); - if (!retval) - retval = put_user(0, &infop->si_code); - if (!retval) - retval = put_user(0, &infop->si_pid); - if (!retval) - retval = put_user(0, &infop->si_uid); - if (!retval) - retval = put_user(0, &infop->si_status); - } - } - return retval; -} - -SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *, - infop, int, options, struct rusage __user *, ru) -{ - struct pid *pid = NULL; - enum pid_type type; - long ret; - - if (options & ~(WNOHANG|WNOWAIT|WEXITED|WSTOPPED|WCONTINUED)) - return -EINVAL; - if (!(options & (WEXITED|WSTOPPED|WCONTINUED))) - return -EINVAL; - - switch (which) { - case P_ALL: - type = PIDTYPE_MAX; - break; - case P_PID: - type = PIDTYPE_PID; - if (upid <= 0) - return -EINVAL; - break; - case P_PGID: - type = PIDTYPE_PGID; - if (upid <= 0) - return -EINVAL; - break; - default: - return -EINVAL; - } - - if (type < PIDTYPE_MAX) - pid = find_get_pid(upid); - ret = do_wait(type, pid, options, infop, NULL, ru); - put_pid(pid); - - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(5, ret, which, upid, infop, options, ru); - return ret; -} - -SYSCALL_DEFINE4(wait4, pid_t, upid, int __user *, stat_addr, - int, options, struct rusage __user *, ru) -{ - struct pid *pid = NULL; - enum pid_type type; - long ret; - - if (options & ~(WNOHANG|WUNTRACED|WCONTINUED| - __WNOTHREAD|__WCLONE|__WALL)) - return -EINVAL; - - if (upid == -1) - type = PIDTYPE_MAX; - else if (upid < 0) { - type = PIDTYPE_PGID; - pid = find_get_pid(-upid); - } else if (upid == 0) { - type = PIDTYPE_PGID; - pid = get_pid(task_pgrp(current)); - } else /* upid > 0 */ { - type = PIDTYPE_PID; - pid = find_get_pid(upid); - } - - ret = do_wait(type, pid, options | WEXITED, NULL, stat_addr, ru); - put_pid(pid); - - /* avoid REGPARM breakage on x86: */ - asmlinkage_protect(4, ret, upid, stat_addr, options, ru); - return ret; -} - -#ifdef __ARCH_WANT_SYS_WAITPID - -/* - * sys_waitpid() remains for compatibility. waitpid() should be - * implemented by calling sys_wait4() from libc.a. - */ -SYSCALL_DEFINE3(waitpid, pid_t, pid, int __user *, stat_addr, int, options) -{ - return sys_wait4(pid, stat_addr, options, NULL); -} - -#endif -#endif |