Btrfs-progs: Add chunk recover function - using old chunk items

Add chunk-recover program to check or rebuild chunk tree when the system
chunk array or chunk tree is broken.

Due to the importance of the system chunk array and chunk tree, if one of
them is broken, the whole btrfs will be broken even other data are OK.

But we have some hint(fsid, checksum...) to salvage the old metadata.
So this function will first scan the whole file system and collect the
needed data(chunk/block group/dev extent), and check for the references
between them. If the references are OK, the chunk tree can be rebuilt and
luckily the file system will be mountable.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/disk-io.h b/disk-io.h
index e845459a..5fed663c 100644
--- a/disk-io.h
+++ b/disk-io.h
@@ -92,6 +92,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 int btrfs_open_device(struct btrfs_device *dev);
 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_sectorsize,
 			 int verify);
+int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size);
 int csum_tree_block(struct btrfs_root *root, struct extent_buffer *buf,
 		    int verify);
 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);