Btrfs: superblock duplication

This patch implements superblock duplication. Superblocks
are stored at offset 16K, 64M and 256G on every devices.
Spaces used by superblocks are preserved by the allocator,
which uses a reverse mapping function to find the logical
addresses that correspond to superblocks. Thank you,

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>

1 files changed, 0 insertions, 1 deletions

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 09462adfbe33..2e69b9c30437 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -290,7 +290,6 @@ __btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
                         ret = -EINVAL;
                         goto out;
                 }
-
                 unlink_free_space(block_group, info);
 
                 if (info->bytes == bytes) {