Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris...

[firefly-linux-kernel-4.4.55.git] / kernel / cgroup.c

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 746055b214d7a84077bb5a166dd477d357ae9a84..51cddc11cd85c847ec0fee3cd9a00fae3b66b4b0 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -876,25 +876,29 @@ static void cgroup_clear_directory(struct dentry *dentry)
        struct list_head *node;
 
        BUG_ON(!mutex_is_locked(&dentry->d_inode->i_mutex));
-       spin_lock(&dcache_lock);
+       spin_lock(&dentry->d_lock);
        node = dentry->d_subdirs.next;
        while (node != &dentry->d_subdirs) {
                struct dentry *d = list_entry(node, struct dentry, d_u.d_child);
+
+               spin_lock_nested(&d->d_lock, DENTRY_D_LOCK_NESTED);
                list_del_init(node);
                if (d->d_inode) {
                        /* This should never be called on a cgroup
                         * directory with child cgroups */
                        BUG_ON(d->d_inode->i_mode & S_IFDIR);
-                       d = dget_locked(d);
-                       spin_unlock(&dcache_lock);
+                       dget_dlock(d);
+                       spin_unlock(&d->d_lock);
+                       spin_unlock(&dentry->d_lock);
                        d_delete(d);
                        simple_unlink(dentry->d_inode, d);
                        dput(d);
-                       spin_lock(&dcache_lock);
-               }
+                       spin_lock(&dentry->d_lock);
+               } else
+                       spin_unlock(&d->d_lock);
                node = dentry->d_subdirs.next;
        }
-       spin_unlock(&dcache_lock);
+       spin_unlock(&dentry->d_lock);
 }
 
 /*
@@ -902,11 +906,16 @@ static void cgroup_clear_directory(struct dentry *dentry)
  */
 static void cgroup_d_remove_dir(struct dentry *dentry)
 {
+       struct dentry *parent;
+
        cgroup_clear_directory(dentry);
 
-       spin_lock(&dcache_lock);
+       parent = dentry->d_parent;
+       spin_lock(&parent->d_lock);
+       spin_lock(&dentry->d_lock);
        list_del_init(&dentry->d_u.d_child);
-       spin_unlock(&dcache_lock);
+       spin_unlock(&dentry->d_lock);
+       spin_unlock(&parent->d_lock);
        remove_dir(dentry);
 }
 
@@ -2213,7 +2222,7 @@ static struct dentry *cgroup_lookup(struct inode *dir,
 
        if (dentry->d_name.len > NAME_MAX)
                return ERR_PTR(-ENAMETOOLONG);
-       dentry->d_op = &cgroup_dentry_operations;
+       d_set_d_op(dentry, &cgroup_dentry_operations);
        d_add(dentry, NULL);
        return NULL;
 }
@@ -3655,9 +3664,7 @@ again:
        list_del(&cgrp->sibling);
        cgroup_unlock_hierarchy(cgrp->root);
 
-       spin_lock(&cgrp->dentry->d_lock);
        d = dget(cgrp->dentry);
-       spin_unlock(&d->d_lock);
 
        cgroup_d_remove_dir(d);
        dput(d);