diff options
Diffstat (limited to 'kernel/pid.c')
| -rw-r--r-- | kernel/pid.c | 41 |
1 files changed, 23 insertions, 18 deletions
diff --git a/kernel/pid.c b/kernel/pid.c index 477691576b3..20d59fa2d49 100644 --- a/kernel/pid.c +++ b/kernel/pid.c @@ -111,10 +111,11 @@ EXPORT_SYMBOL(is_container_init); static __cacheline_aligned_in_smp DEFINE_SPINLOCK(pidmap_lock); -static void free_pidmap(struct pid_namespace *pid_ns, int pid) +static void free_pidmap(struct upid *upid) { - struct pidmap *map = pid_ns->pidmap + pid / BITS_PER_PAGE; - int offset = pid & BITS_PER_PAGE_MASK; + int nr = upid->nr; + struct pidmap *map = upid->ns->pidmap + nr / BITS_PER_PAGE; + int offset = nr & BITS_PER_PAGE_MASK; clear_bit(offset, map->page); atomic_inc(&map->nr_free); @@ -232,7 +233,7 @@ void free_pid(struct pid *pid) spin_unlock_irqrestore(&pidmap_lock, flags); for (i = 0; i <= pid->level; i++) - free_pidmap(pid->numbers[i].ns, pid->numbers[i].nr); + free_pidmap(pid->numbers + i); call_rcu(&pid->rcu, delayed_put_pid); } @@ -278,8 +279,8 @@ out: return pid; out_free: - for (i++; i <= ns->level; i++) - free_pidmap(pid->numbers[i].ns, pid->numbers[i].nr); + while (++i <= ns->level) + free_pidmap(pid->numbers + i); kmem_cache_free(ns->pid_cachep, pid); pid = NULL; @@ -316,7 +317,7 @@ EXPORT_SYMBOL_GPL(find_pid); /* * attach_pid() must be called with the tasklist_lock write-held. */ -int attach_pid(struct task_struct *task, enum pid_type type, +void attach_pid(struct task_struct *task, enum pid_type type, struct pid *pid) { struct pid_link *link; @@ -324,11 +325,10 @@ int attach_pid(struct task_struct *task, enum pid_type type, link = &task->pids[type]; link->pid = pid; hlist_add_head_rcu(&link->node, &pid->tasks[type]); - - return 0; } -void detach_pid(struct task_struct *task, enum pid_type type) +static void __change_pid(struct task_struct *task, enum pid_type type, + struct pid *new) { struct pid_link *link; struct pid *pid; @@ -338,7 +338,7 @@ void detach_pid(struct task_struct *task, enum pid_type type) pid = link->pid; hlist_del_rcu(&link->node); - link->pid = NULL; + link->pid = new; for (tmp = PIDTYPE_MAX; --tmp >= 0; ) if (!hlist_empty(&pid->tasks[tmp])) @@ -347,13 +347,24 @@ void detach_pid(struct task_struct *task, enum pid_type type) free_pid(pid); } +void detach_pid(struct task_struct *task, enum pid_type type) +{ + __change_pid(task, type, NULL); +} + +void change_pid(struct task_struct *task, enum pid_type type, + struct pid *pid) +{ + __change_pid(task, type, pid); + attach_pid(task, type, pid); +} + /* transfer_pid is an optimization of attach_pid(new), detach_pid(old) */ void transfer_pid(struct task_struct *old, struct task_struct *new, enum pid_type type) { new->pids[type].pid = old->pids[type].pid; hlist_replace_rcu(&old->pids[type].node, &new->pids[type].node); - old->pids[type].pid = NULL; } struct task_struct *pid_task(struct pid *pid, enum pid_type type) @@ -380,12 +391,6 @@ struct task_struct *find_task_by_pid_type_ns(int type, int nr, EXPORT_SYMBOL(find_task_by_pid_type_ns); -struct task_struct *find_task_by_pid(pid_t nr) -{ - return find_task_by_pid_type_ns(PIDTYPE_PID, nr, &init_pid_ns); -} -EXPORT_SYMBOL(find_task_by_pid); - struct task_struct *find_task_by_vpid(pid_t vnr) { return find_task_by_pid_type_ns(PIDTYPE_PID, vnr, |