From: Liu Bo Date: Wed, 14 Sep 2016 15:51:46 +0000 (-0700) Subject: Btrfs: return gracefully from balance if fs tree is corrupted X-Git-Tag: firefly_0821_release~176^2~4^2~7^2~39 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=8ca6845a58cda0cda9359eb313af35c2f88df073;p=firefly-linux-kernel-4.4.55.git Btrfs: return gracefully from balance if fs tree is corrupted commit 3561b9db70928f207be4570b48fc19898eeaef54 upstream. When relocating tree blocks, we firstly get block information from back references in the extent tree, we then search fs tree to try to find all parents of a block. However, if fs tree is corrupted, eg. if there're some missing items, we could come across these WARN_ONs and BUG_ONs. This makes us print some error messages and return gracefully from balance. Signed-off-by: Liu Bo Reviewed-by: Josef Bacik Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index b4ca5454ef1a..937d015422e0 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -921,9 +921,16 @@ again: path2->slots[level]--; eb = path2->nodes[level]; - WARN_ON(btrfs_node_blockptr(eb, path2->slots[level]) != - cur->bytenr); - + if (btrfs_node_blockptr(eb, path2->slots[level]) != + cur->bytenr) { + btrfs_err(root->fs_info, + "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)", + cur->bytenr, level - 1, root->objectid, + node_key->objectid, node_key->type, + node_key->offset); + err = -ENOENT; + goto out; + } lower = cur; need_check = true; for (; level < BTRFS_MAX_LEVEL; level++) { @@ -2676,11 +2683,15 @@ static int do_relocation(struct btrfs_trans_handle *trans, if (!upper->eb) { ret = btrfs_search_slot(trans, root, key, path, 0, 1); - if (ret < 0) { - err = ret; + if (ret) { + if (ret < 0) + err = ret; + else + err = -ENOENT; + + btrfs_release_path(path); break; } - BUG_ON(ret > 0); if (!upper->eb) { upper->eb = path->nodes[upper->level];