diff options
| -rw-r--r-- | fs/dcache.c | 49 |
1 files changed, 23 insertions, 26 deletions
diff --git a/fs/dcache.c b/fs/dcache.c index 0a58038091f2..c159a4b304cf 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -2773,25 +2773,6 @@ static void copy_name(struct dentry *dentry, struct dentry *target) kfree_rcu(old_name, u.head); } -static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target) -{ - if (IS_ROOT(dentry) || dentry->d_parent == target->d_parent) - spin_lock(&target->d_parent->d_lock); - else { - if (d_ancestor(dentry->d_parent, target->d_parent)) { - spin_lock(&dentry->d_parent->d_lock); - spin_lock_nested(&target->d_parent->d_lock, - DENTRY_D_LOCK_NESTED); - } else { - spin_lock(&target->d_parent->d_lock); - spin_lock_nested(&dentry->d_parent->d_lock, - DENTRY_D_LOCK_NESTED); - } - } - spin_lock_nested(&dentry->d_lock, 2); - spin_lock_nested(&target->d_lock, 3); -} - /* * __d_move - move a dentry * @dentry: entry to move @@ -2806,16 +2787,34 @@ static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target) static void __d_move(struct dentry *dentry, struct dentry *target, bool exchange) { - struct dentry *old_parent; + struct dentry *old_parent, *p; struct inode *dir = NULL; unsigned n; - if (!dentry->d_inode) - printk(KERN_WARNING "VFS: moving negative dcache entry\n"); - BUG_ON(d_ancestor(dentry, target)); + WARN_ON(!dentry->d_inode); + if (WARN_ON(dentry == target)) + return; + BUG_ON(d_ancestor(target, dentry)); + old_parent = dentry->d_parent; + p = d_ancestor(old_parent, target); + if (IS_ROOT(dentry)) { + BUG_ON(p); + spin_lock(&target->d_parent->d_lock); + } else if (!p) { + /* target is not a descendent of dentry->d_parent */ + spin_lock(&target->d_parent->d_lock); + spin_lock_nested(&old_parent->d_lock, DENTRY_D_LOCK_NESTED); + } else { + BUG_ON(p == dentry); + spin_lock(&old_parent->d_lock); + if (p != target) + spin_lock_nested(&target->d_parent->d_lock, + DENTRY_D_LOCK_NESTED); + } + spin_lock_nested(&dentry->d_lock, 2); + spin_lock_nested(&target->d_lock, 3); - dentry_lock_for_move(dentry, target); if (unlikely(d_in_lookup(target))) { dir = target->d_parent->d_inode; n = start_dir_add(dir); @@ -2825,8 +2824,6 @@ static void __d_move(struct dentry *dentry, struct dentry *target, write_seqcount_begin(&dentry->d_seq); write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED); - old_parent = dentry->d_parent; - /* unhash both */ if (!d_unhashed(dentry)) ___d_drop(dentry); |