diff options
| author | Filipe Manana <fdmanana@suse.com> | 2014-07-02 20:07:54 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-09-05 16:36:37 -0700 |
| commit | 480f1ea5e0697c721149fb6abe93652dc48e30ae (patch) | |
| tree | 6edc8563e1d6917b8f6d0c87a58e7965fe93a060 | |
| parent | 4dc6ec45580779f8d79972d32ffe7501f6f5cf6d (diff) | |
Btrfs: read lock extent buffer while walking backrefs
commit 6f7ff6d7832c6be13e8c95598884dbc40ad69fb7 upstream.
Before processing the extent buffer, acquire a read lock on it, so
that we're safe against concurrent updates on the extent buffer.
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Chris Mason <clm@fb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/btrfs/backref.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index d7a24620a963..54a201dac7f9 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -1000,8 +1000,11 @@ again: ret = -EIO; goto out; } + btrfs_tree_read_lock(eb); + btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK); ret = find_extent_in_eb(eb, bytenr, *extent_item_pos, &eie); + btrfs_tree_read_unlock_blocking(eb); free_extent_buffer(eb); if (ret < 0) goto out; |