btrfs: merge btrfs_read_dev_one_super() into btrfs_read_disk_super()

We have two functions to read a super block from a block device:

- btrfs_read_dev_one_super()
  Exported from disk-io.c

- btrfs_read_disk_super()
  Local to volumes.c

And they have some minor differences:

- btrfs_read_dev_one_super() uses @copy_num
  Meanwhile btrfs_read_disk_super() relies on the physical and expected
  bytenr passed from the caller.

  The parameter list of btrfs_read_dev_one_super() is more user
  friendly.

- btrfs_read_disk_super() makes sure the label is NUL terminated

We do not need two different functions doing the same job, so merge the
behavior into btrfs_read_disk_super() by:

- Remove btrfs_read_dev_one_super()

- Export btrfs_read_disk_super()
  The name pairs with btrfs_release_disk_super() perfectly.

- Change the parameter list of btrfs_read_disk_super() to mimic
  btrfs_read_dev_one_super()
  All existing callers are calculating the physical address and expect
  bytenr before calling btrfs_read_disk_super() already.

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 0 insertions, 2 deletions

diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index f87bbb7f8e7e..0ac9baf1215f 100644
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -59,8 +59,6 @@ int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
 int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount);
 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
-struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
-						   int copy_num, bool drop_cache);
 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
 					const struct btrfs_key *key);