path: root/Documentation/btrfs-rescue.asciidoc
diff options
authorDavid Sterba <>2013-11-13 18:55:12 +0100
committerDavid Sterba <>2015-04-22 18:21:48 +0200
commit49eab991720a1dbeaffade98fb946f6a22848867 (patch)
treef1c86951673c329fd67b9266009f75bd9c361179 /Documentation/btrfs-rescue.asciidoc
parentc8927d51164f68a5c96090c5f52d8ffa81ec98b7 (diff)
btrfs-progs: add zero-log to rescue command
Copy the functionality of standalone btrfs-zero-log to the main tool. Delete man page for btrfs-zero-log and copy the relevant parts into btrfs-rescue(8). The standalone utility will be removed later. Signed-off-by: David Sterba <>
Diffstat (limited to 'Documentation/btrfs-rescue.asciidoc')
1 files changed, 24 insertions, 0 deletions
diff --git a/Documentation/btrfs-rescue.asciidoc b/Documentation/btrfs-rescue.asciidoc
index e0acf091..32d8a927 100644
--- a/Documentation/btrfs-rescue.asciidoc
+++ b/Documentation/btrfs-rescue.asciidoc
@@ -40,6 +40,30 @@ assume an answer of 'yes' to all questions.
verbose mode.
+*zero-log* <device>::
+clear out log tree
+*btrfs rescue zero-log* will remove the log tree if log tree is corrupt, which
+will allow you to mount the filesystem again.
+The common case where this happens has been fixed a long time ago,
+so it is unlikely that you will see this particular problem.
+One can determine whether *btrfs-zero-log* is needed according to the kernel
+? replay_one_dir_item+0xb5/0xb5 [btrfs]
+? walk_log_tree+0x9c/0x19d [btrfs]
+? btrfs_read_fs_root_no_radix+0x169/0x1a1 [btrfs]
+? btrfs_recover_log_trees+0x195/0x29c [btrfs]
+? replay_one_dir_item+0xb5/0xb5 [btrfs]
+? btree_read_extent_buffer_pages+0x76/0xbc [btrfs]
+? open_ctree+0xff6/0x132c [btrfs]
+If the errors are like above, then *zero-log* could be used to clear
+the log and the filesystem may be mounted normally again.
*btrfs rescue* returns a zero exit status if it succeeds. Non zero is