Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f1ca7e98 authored by Josef Bacik's avatar Josef Bacik
Browse files

Btrfs: hold the tree mod lock in __tree_mod_log_rewind 



We need to hold the tree mod log lock in __tree_mod_log_rewind since we walk
forward in the tree mod entries, otherwise we'll end up with random entries and
trip the BUG_ON() at the front of __tree_mod_log_rewind.  This fixes the panics
people were seeing when running

find /whatever -type f -exec btrfs fi defrag {} \;

Thansk,

Cc: stable@vger.kernel.org
Signed-off-by: default avatarJosef Bacik <jbacik@fusionio.com>
parent 261c84b6

fs/btrfs/ctree.c

+6 −4
Original line number Diff line number Diff line
@@ -1161,8 +1161,8 @@ __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info, 
 * time_seq).

 */

static void

__tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq,

		      struct tree_mod_elem *first_tm)

__tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,

		      u64 time_seq, struct tree_mod_elem *first_tm)

{

	u32 n;

	struct rb_node *next;
@@ -1172,6 +1172,7 @@ __tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq, 
	unsigned long p_size = sizeof(struct btrfs_key_ptr);



	n = btrfs_header_nritems(eb);

	tree_mod_log_read_lock(fs_info);

	while (tm && tm->seq >= time_seq) {

		/*

		 * all the operations are recorded with the operator used for
@@ -1226,6 +1227,7 @@ __tree_mod_log_rewind(struct extent_buffer *eb, u64 time_seq, 
		if (tm->index != first_tm->index)

			break;

	}

	tree_mod_log_read_unlock(fs_info);

	btrfs_set_header_nritems(eb, n);

}
@@ -1274,7 +1276,7 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb, 


	extent_buffer_get(eb_rewin);

	btrfs_tree_read_lock(eb_rewin);

	__tree_mod_log_rewind(eb_rewin, time_seq, tm);

	__tree_mod_log_rewind(fs_info, eb_rewin, time_seq, tm);

	WARN_ON(btrfs_header_nritems(eb_rewin) >

		BTRFS_NODEPTRS_PER_BLOCK(fs_info->tree_root));
@@ -1350,7 +1352,7 @@ get_old_root(struct btrfs_root *root, u64 time_seq) 
		btrfs_set_header_generation(eb, old_generation);

	}

	if (tm)

		__tree_mod_log_rewind(eb, time_seq, tm);

		__tree_mod_log_rewind(root->fs_info, eb, time_seq, tm);

	else

		WARN_ON(btrfs_header_level(eb) != 0);

	WARN_ON(btrfs_header_nritems(eb) > BTRFS_NODEPTRS_PER_BLOCK(root));