btrfs: introduce mount option rescue=ignorebadroots
In the face of extent root corruption, or any other core fs wide root
corruption we will fail to mount the file system. This makes recovery
kind of a pain, because you need to fall back to userspace tools to
scrape off data. Instead provide a mechanism to gracefully handle bad
roots, so we can at least mount read-only and possibly recover data from
the file system.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 7e1eb57..972fb68 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -150,7 +150,7 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio,
struct compressed_bio *cb = bio->bi_private;
u8 *cb_sum = cb->sums;
- if (inode->flags & BTRFS_INODE_NODATASUM)
+ if (!fs_info->csum_root || (inode->flags & BTRFS_INODE_NODATASUM))
return 0;
shash->tfm = fs_info->csum_shash;