Commit 856bf3e5 authored by Chris Mason's avatar Chris Mason
Browse files

Btrfs: Avoid extent_buffer lru corruption 



Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 257d0ce3

fs/btrfs/extent_map.c

+7 −1
Original line number Diff line number Diff line
@@ -2047,7 +2047,7 @@ static int add_lru(struct extent_map_tree *tree, struct extent_buffer *eb) 
			rm = list_entry(tree->buffer_lru.prev,

					struct extent_buffer, lru);

			tree->lru_size--;

			list_del(&rm->lru);

			list_del_init(&rm->lru);

			free_extent_buffer(rm);

		}

	} else
@@ -2187,6 +2187,9 @@ struct extent_buffer *alloc_extent_buffer(struct extent_map_tree *tree, 
	return eb;



fail:

	spin_lock(&tree->lru_lock);

	list_del_init(&eb->lru);

	spin_unlock(&tree->lru_lock);

	if (!atomic_dec_and_test(&eb->refs))

		return NULL;

	for (index = 0; index < i; index++) {
@@ -2246,6 +2249,9 @@ struct extent_buffer *find_extent_buffer(struct extent_map_tree *tree, 
	spin_unlock(&tree->lru_lock);

	return eb;

fail:

	spin_lock(&tree->lru_lock);

	list_del_init(&eb->lru);

	spin_unlock(&tree->lru_lock);

	if (!atomic_dec_and_test(&eb->refs))

		return NULL;

	for (index = 0; index < i; index++) {