thp: update futex compound knowledge

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

diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index 746055b214d7a84077bb5a166dd477d357ae9a84..5c5f4cc2e99a8b36ea19f0841e10d80937e58b38 100644 (file)
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -763,8 +763,6 @@ EXPORT_SYMBOL_GPL(cgroup_unlock);
  * -> cgroup_mkdir.
  */
 
-static struct dentry *cgroup_lookup(struct inode *dir,
-                       struct dentry *dentry, struct nameidata *nd);
 static int cgroup_mkdir(struct inode *dir, struct dentry *dentry, int mode);
 static int cgroup_rmdir(struct inode *unused_dir, struct dentry *dentry);
 static int cgroup_populate_dir(struct cgroup *cgrp);
@@ -876,25 +874,29 @@ 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 +904,16 @@ 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);
 }
 
@@ -1442,6 +1449,10 @@ static int cgroup_set_super(struct super_block *sb, void *data)
 
 static int cgroup_get_rootdir(struct super_block *sb)
 {
+       static const struct dentry_operations cgroup_dops = {
+               .d_iput = cgroup_diput,
+       };
+
        struct inode *inode =
                cgroup_new_inode(S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR, sb);
        struct dentry *dentry;
@@ -1459,6 +1470,8 @@ static int cgroup_get_rootdir(struct super_block *sb)
                return -ENOMEM;
        }
        sb->s_root = dentry;
+       /* for everything else we want ->d_op set */
+       sb->s_d_op = &cgroup_dops;
        return 0;
 }
 
@@ -2182,7 +2195,7 @@ static const struct file_operations cgroup_file_operations = {
 };
 
 static const struct inode_operations cgroup_dir_inode_operations = {
-       .lookup = cgroup_lookup,
+       .lookup = simple_lookup,
        .mkdir = cgroup_mkdir,
        .rmdir = cgroup_rmdir,
        .rename = cgroup_rename,
@@ -2198,26 +2211,6 @@ static inline struct cftype *__file_cft(struct file *file)
        return __d_cft(file->f_dentry);
 }
 
-static int cgroup_delete_dentry(const struct dentry *dentry)
-{
-       return 1;
-}
-
-static struct dentry *cgroup_lookup(struct inode *dir,
-                       struct dentry *dentry, struct nameidata *nd)
-{
-       static const struct dentry_operations cgroup_dentry_operations = {
-               .d_delete = cgroup_delete_dentry,
-               .d_iput = cgroup_diput,
-       };
-
-       if (dentry->d_name.len > NAME_MAX)
-               return ERR_PTR(-ENAMETOOLONG);
-       dentry->d_op = &cgroup_dentry_operations;
-       d_add(dentry, NULL);
-       return NULL;
-}
-
 static int cgroup_create_file(struct dentry *dentry, mode_t mode,
                                struct super_block *sb)
 {
@@ -3655,9 +3648,7 @@ 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);