btrfs: remove the start argument from btrfs_free_reserved_data_space_noquota()

The start argument for btrfs_free_reserved_data_space_noquota() is only
used to make sure the amount of bytes we decrement from the bytes_may_use
counter of the data space_info object is aligned to the filesystem's
sector size. It serves no other purpose.

All its current callers always pass a length argument that is already
aligned to the sector size, so we can make the start argument go away.
In fact its presence makes it impossible to use it in a context where we
just want to free a number of bytes for a range for which either we do
not know its start offset or for freeing multiple ranges at once (which
are not contiguous).

This change is preparatory work for a patch (third patch in this series)
that makes relocation of data block groups that are not full reserve less
data space.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 4 insertions, 7 deletions

diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index 1245739a3a6e..d05648f882ca 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -255,7 +255,7 @@ int btrfs_check_data_free_space(struct inode *inode,
 	/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
 	ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
 	if (ret < 0)
-		btrfs_free_reserved_data_space_noquota(inode, start, len);
+		btrfs_free_reserved_data_space_noquota(inode, len);
 	else
 		ret = 0;
 	return ret;
@@ -269,16 +269,13 @@ int btrfs_check_data_free_space(struct inode *inode,
  * which we can't sleep and is sure it won't affect qgroup reserved space.
  * Like clear_bit_hook().
  */
-void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
+void btrfs_free_reserved_data_space_noquota(struct inode *inode,
 					    u64 len)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
 	struct btrfs_space_info *data_sinfo;
 
-	/* Make sure the range is aligned to sectorsize */
-	len = round_up(start + len, fs_info->sectorsize) -
-	      round_down(start, fs_info->sectorsize);
-	start = round_down(start, fs_info->sectorsize);
+	ASSERT(IS_ALIGNED(len, fs_info->sectorsize));
 
 	data_sinfo = fs_info->data_sinfo;
 	spin_lock(&data_sinfo->lock);
@@ -303,7 +300,7 @@ void btrfs_free_reserved_data_space(struct inode *inode,
 	      round_down(start, root->fs_info->sectorsize);
 	start = round_down(start, root->fs_info->sectorsize);
 
-	btrfs_free_reserved_data_space_noquota(inode, start, len);
+	btrfs_free_reserved_data_space_noquota(inode, len);
 	btrfs_qgroup_free_data(inode, reserved, start, len);
 }