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-rw-r--r--kernel/cgroup.c116
1 files changed, 0 insertions, 116 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 00a884342d3d..2731d115d725 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -4630,122 +4630,6 @@ void cgroup_exit(struct task_struct *tsk, int run_callbacks)
4630} 4630}
4631 4631
4632/** 4632/**
4633 * cgroup_clone - clone the cgroup the given subsystem is attached to
4634 * @tsk: the task to be moved
4635 * @subsys: the given subsystem
4636 * @nodename: the name for the new cgroup
4637 *
4638 * Duplicate the current cgroup in the hierarchy that the given
4639 * subsystem is attached to, and move this task into the new
4640 * child.
4641 */
4642int cgroup_clone(struct task_struct *tsk, struct cgroup_subsys *subsys,
4643 char *nodename)
4644{
4645 struct dentry *dentry;
4646 int ret = 0;
4647 struct cgroup *parent, *child;
4648 struct inode *inode;
4649 struct css_set *cg;
4650 struct cgroupfs_root *root;
4651 struct cgroup_subsys *ss;
4652
4653 /* We shouldn't be called by an unregistered subsystem */
4654 BUG_ON(!subsys->active);
4655
4656 /* First figure out what hierarchy and cgroup we're dealing
4657 * with, and pin them so we can drop cgroup_mutex */
4658 mutex_lock(&cgroup_mutex);
4659 again:
4660 root = subsys->root;
4661 if (root == &rootnode) {
4662 mutex_unlock(&cgroup_mutex);
4663 return 0;
4664 }
4665
4666 /* Pin the hierarchy */
4667 if (!atomic_inc_not_zero(&root->sb->s_active)) {
4668 /* We race with the final deactivate_super() */
4669 mutex_unlock(&cgroup_mutex);
4670 return 0;
4671 }
4672
4673 /* Keep the cgroup alive */
4674 task_lock(tsk);
4675 parent = task_cgroup(tsk, subsys->subsys_id);
4676 cg = tsk->cgroups;
4677 get_css_set(cg);
4678 task_unlock(tsk);
4679
4680 mutex_unlock(&cgroup_mutex);
4681
4682 /* Now do the VFS work to create a cgroup */
4683 inode = parent->dentry->d_inode;
4684
4685 /* Hold the parent directory mutex across this operation to
4686 * stop anyone else deleting the new cgroup */
4687 mutex_lock(&inode->i_mutex);
4688 dentry = lookup_one_len(nodename, parent->dentry, strlen(nodename));
4689 if (IS_ERR(dentry)) {
4690 printk(KERN_INFO
4691 "cgroup: Couldn't allocate dentry for %s: %ld\n", nodename,
4692 PTR_ERR(dentry));
4693 ret = PTR_ERR(dentry);
4694 goto out_release;
4695 }
4696
4697 /* Create the cgroup directory, which also creates the cgroup */
4698 ret = vfs_mkdir(inode, dentry, 0755);
4699 child = __d_cgrp(dentry);
4700 dput(dentry);
4701 if (ret) {
4702 printk(KERN_INFO
4703 "Failed to create cgroup %s: %d\n", nodename,
4704 ret);
4705 goto out_release;
4706 }
4707
4708 /* The cgroup now exists. Retake cgroup_mutex and check
4709 * that we're still in the same state that we thought we
4710 * were. */
4711 mutex_lock(&cgroup_mutex);
4712 if ((root != subsys->root) ||
4713 (parent != task_cgroup(tsk, subsys->subsys_id))) {
4714 /* Aargh, we raced ... */
4715 mutex_unlock(&inode->i_mutex);
4716 put_css_set(cg);
4717
4718 deactivate_super(root->sb);
4719 /* The cgroup is still accessible in the VFS, but
4720 * we're not going to try to rmdir() it at this
4721 * point. */
4722 printk(KERN_INFO
4723 "Race in cgroup_clone() - leaking cgroup %s\n",
4724 nodename);
4725 goto again;
4726 }
4727
4728 /* do any required auto-setup */
4729 for_each_subsys(root, ss) {
4730 if (ss->post_clone)
4731 ss->post_clone(ss, child);
4732 }
4733
4734 /* All seems fine. Finish by moving the task into the new cgroup */
4735 ret = cgroup_attach_task(child, tsk);
4736 mutex_unlock(&cgroup_mutex);
4737
4738 out_release:
4739 mutex_unlock(&inode->i_mutex);
4740
4741 mutex_lock(&cgroup_mutex);
4742 put_css_set(cg);
4743 mutex_unlock(&cgroup_mutex);
4744 deactivate_super(root->sb);
4745 return ret;
4746}
4747
4748/**
4749 * cgroup_is_descendant - see if @cgrp is a descendant of @task's cgrp 4633 * cgroup_is_descendant - see if @cgrp is a descendant of @task's cgrp
4750 * @cgrp: the cgroup in question 4634 * @cgrp: the cgroup in question
4751 * @task: the task in question 4635 * @task: the task in question