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Diffstat (limited to 'kernel/cgroup.c')
-rw-r--r--kernel/cgroup.c76
1 files changed, 12 insertions, 64 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 2097684cf19..79818507e44 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -822,7 +822,7 @@ EXPORT_SYMBOL_GPL(cgroup_unlock);
*/
static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode);
-static struct dentry *cgroup_lookup(struct inode *, struct dentry *, struct nameidata *);
+static struct dentry *cgroup_lookup(struct inode *, struct dentry *, unsigned int);
static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
static int cgroup_populate_dir(struct cgroup *cgrp);
static const struct inode_operations cgroup_dir_inode_operations;
@@ -901,13 +901,10 @@ static void cgroup_diput(struct dentry *dentry, struct inode *inode)
mutex_unlock(&cgroup_mutex);
/*
- * We want to drop the active superblock reference from the
- * cgroup creation after all the dentry refs are gone -
- * kill_sb gets mighty unhappy otherwise. Mark
- * dentry->d_fsdata with cgroup_diput() to tell
- * cgroup_d_release() to call deactivate_super().
+ * Drop the active superblock reference that we took when we
+ * created the cgroup
*/
- dentry->d_fsdata = cgroup_diput;
+ deactivate_super(cgrp->root->sb);
/*
* if we're getting rid of the cgroup, refcount should ensure
@@ -933,13 +930,6 @@ static int cgroup_delete(const struct dentry *d)
return 1;
}
-static void cgroup_d_release(struct dentry *dentry)
-{
- /* did cgroup_diput() tell me to deactivate super? */
- if (dentry->d_fsdata == cgroup_diput)
- deactivate_super(dentry->d_sb);
-}
-
static void remove_dir(struct dentry *d)
{
struct dentry *parent = dget(d->d_parent);
@@ -964,7 +954,7 @@ static int cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft)
dget(d);
d_delete(d);
- simple_unlink(d->d_inode, d);
+ simple_unlink(cgrp->dentry->d_inode, d);
list_del_init(&cfe->node);
dput(d);
@@ -1078,28 +1068,24 @@ static int rebind_subsystems(struct cgroupfs_root *root,
BUG_ON(cgrp->subsys[i]);
BUG_ON(!dummytop->subsys[i]);
BUG_ON(dummytop->subsys[i]->cgroup != dummytop);
- mutex_lock(&ss->hierarchy_mutex);
cgrp->subsys[i] = dummytop->subsys[i];
cgrp->subsys[i]->cgroup = cgrp;
list_move(&ss->sibling, &root->subsys_list);
ss->root = root;
if (ss->bind)
ss->bind(cgrp);
- mutex_unlock(&ss->hierarchy_mutex);
/* refcount was already taken, and we're keeping it */
} else if (bit & removed_bits) {
/* We're removing this subsystem */
BUG_ON(ss == NULL);
BUG_ON(cgrp->subsys[i] != dummytop->subsys[i]);
BUG_ON(cgrp->subsys[i]->cgroup != cgrp);
- mutex_lock(&ss->hierarchy_mutex);
if (ss->bind)
ss->bind(dummytop);
dummytop->subsys[i]->cgroup = dummytop;
cgrp->subsys[i] = NULL;
subsys[i]->root = &rootnode;
list_move(&ss->sibling, &rootnode.subsys_list);
- mutex_unlock(&ss->hierarchy_mutex);
/* subsystem is now free - drop reference on module */
module_put(ss->module);
} else if (bit & final_bits) {
@@ -1547,7 +1533,6 @@ static int cgroup_get_rootdir(struct super_block *sb)
static const struct dentry_operations cgroup_dops = {
.d_iput = cgroup_diput,
.d_delete = cgroup_delete,
- .d_release = cgroup_d_release,
};
struct inode *inode =
@@ -1598,7 +1583,7 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
opts.new_root = new_root;
/* Locate an existing or new sb for this hierarchy */
- sb = sget(fs_type, cgroup_test_super, cgroup_set_super, &opts);
+ sb = sget(fs_type, cgroup_test_super, cgroup_set_super, 0, &opts);
if (IS_ERR(sb)) {
ret = PTR_ERR(sb);
cgroup_drop_root(opts.new_root);
@@ -2581,7 +2566,7 @@ static const struct inode_operations cgroup_dir_inode_operations = {
.rename = cgroup_rename,
};
-static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry *cgroup_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
{
if (dentry->d_name.len > NAME_MAX)
return ERR_PTR(-ENAMETOOLONG);
@@ -3894,8 +3879,12 @@ static void css_dput_fn(struct work_struct *work)
{
struct cgroup_subsys_state *css =
container_of(work, struct cgroup_subsys_state, dput_work);
+ struct dentry *dentry = css->cgroup->dentry;
+ struct super_block *sb = dentry->d_sb;
- dput(css->cgroup->dentry);
+ atomic_inc(&sb->s_active);
+ dput(dentry);
+ deactivate_super(sb);
}
static void init_cgroup_css(struct cgroup_subsys_state *css,
@@ -3922,37 +3911,6 @@ static void init_cgroup_css(struct cgroup_subsys_state *css,
set_bit(CSS_CLEAR_CSS_REFS, &css->flags);
}
-static void cgroup_lock_hierarchy(struct cgroupfs_root *root)
-{
- /* We need to take each hierarchy_mutex in a consistent order */
- int i;
-
- /*
- * No worry about a race with rebind_subsystems that might mess up the
- * locking order, since both parties are under cgroup_mutex.
- */
- for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
- struct cgroup_subsys *ss = subsys[i];
- if (ss == NULL)
- continue;
- if (ss->root == root)
- mutex_lock(&ss->hierarchy_mutex);
- }
-}
-
-static void cgroup_unlock_hierarchy(struct cgroupfs_root *root)
-{
- int i;
-
- for (i = 0; i < CGROUP_SUBSYS_COUNT; i++) {
- struct cgroup_subsys *ss = subsys[i];
- if (ss == NULL)
- continue;
- if (ss->root == root)
- mutex_unlock(&ss->hierarchy_mutex);
- }
-}
-
/*
* cgroup_create - create a cgroup
* @parent: cgroup that will be parent of the new cgroup
@@ -4013,9 +3971,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
ss->post_clone(cgrp);
}
- cgroup_lock_hierarchy(root);
list_add(&cgrp->sibling, &cgrp->parent->children);
- cgroup_unlock_hierarchy(root);
root->number_of_cgroups++;
err = cgroup_create_dir(cgrp, dentry, mode);
@@ -4042,9 +3998,7 @@ static long cgroup_create(struct cgroup *parent, struct dentry *dentry,
err_remove:
- cgroup_lock_hierarchy(root);
list_del(&cgrp->sibling);
- cgroup_unlock_hierarchy(root);
root->number_of_cgroups--;
err_destroy:
@@ -4252,10 +4206,8 @@ again:
list_del_init(&cgrp->release_list);
raw_spin_unlock(&release_list_lock);
- cgroup_lock_hierarchy(cgrp->root);
/* delete this cgroup from parent->children */
list_del_init(&cgrp->sibling);
- cgroup_unlock_hierarchy(cgrp->root);
list_del_init(&cgrp->allcg_node);
@@ -4329,8 +4281,6 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss)
* need to invoke fork callbacks here. */
BUG_ON(!list_empty(&init_task.tasks));
- mutex_init(&ss->hierarchy_mutex);
- lockdep_set_class(&ss->hierarchy_mutex, &ss->subsys_key);
ss->active = 1;
/* this function shouldn't be used with modular subsystems, since they
@@ -4457,8 +4407,6 @@ int __init_or_module cgroup_load_subsys(struct cgroup_subsys *ss)
}
write_unlock(&css_set_lock);
- mutex_init(&ss->hierarchy_mutex);
- lockdep_set_class(&ss->hierarchy_mutex, &ss->subsys_key);
ss->active = 1;
/* success! */