From: Josef Bacik josef@toxicpanda.com
commit 9bc574de590510eff899c3ca8dbaf013566b5efe upstream.
My fsstress modifications coupled with generic/475 uncovered a failure to mount and replay the log if we hit a orphaned root. We do not want to replay the log for an orphan root, but it's completely legitimate to have an orphaned root with a log attached. Fix this by simply skipping replaying the log. We still need to pin it's root node so that we do not overwrite it while replaying other logs, as we re-read the log root at every stage of the replay.
CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Josef Bacik josef@toxicpanda.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- fs/btrfs/tree-log.c | 23 +++++++++++++++++++++-- 1 file changed, 21 insertions(+), 2 deletions(-)
--- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -6018,9 +6018,28 @@ again: wc.replay_dest = btrfs_read_fs_root_no_name(fs_info, &tmp_key); if (IS_ERR(wc.replay_dest)) { ret = PTR_ERR(wc.replay_dest); + + /* + * We didn't find the subvol, likely because it was + * deleted. This is ok, simply skip this log and go to + * the next one. + * + * We need to exclude the root because we can't have + * other log replays overwriting this log as we'll read + * it back in a few more times. This will keep our + * block from being modified, and we'll just bail for + * each subsequent pass. + */ + if (ret == -ENOENT) + ret = btrfs_pin_extent_for_log_replay(fs_info, + log->node->start, + log->node->len); free_extent_buffer(log->node); free_extent_buffer(log->commit_root); kfree(log); + + if (!ret) + goto next; btrfs_handle_fs_error(fs_info, ret, "Couldn't read target root for tree log recovery."); goto error; @@ -6052,7 +6071,6 @@ again: &root->highest_objectid); }
- key.offset = found_key.offset - 1; wc.replay_dest->log_root = NULL; free_extent_buffer(log->node); free_extent_buffer(log->commit_root); @@ -6060,9 +6078,10 @@ again:
if (ret) goto error; - +next: if (found_key.offset == 0) break; + key.offset = found_key.offset - 1; } btrfs_release_path(path);