path: root/Documentation/btrfs-zero-log.asciidoc
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authorDavid Sterba <>2015-04-14 17:37:23 +0200
committerDavid Sterba <>2015-04-14 17:41:27 +0200
commit7ffccaf0c3b4d4979d7d74bab3d79d9541a6e665 (patch)
tree1d64b306503787588d0d79ab467b95f8c6a83c99 /Documentation/btrfs-zero-log.asciidoc
parent32ca2fa502c0a00a7dc40adbdae2e7b7765e6d63 (diff)
btrfs-progs: Documentaion: rename to .asciidoc
A few minor benefits: * editors set highliting according to the extensions * web access to the git repository (github) renders the .asciidoc files: * we can link to them from the wiki * the files are editable via browser and such editations can be submitted for merge easily Signed-off-by: David Sterba <>
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+btrfs-zero-log - clear out log tree
+*btrfs-zero-log* <dev>
+*btrfs-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 *btrfs-zero-log* should be used to clear
+the log and the filesystem may be mounted normally again.
+NOTE: If you use btrfs as the root filesystem, you may want to include
+*btrfs-zero-log* into initramdisk if the log problems hits you often.
+*btrfs-zero-log* will return 0 if no error happened.
+Other exit code means some problems happened.