btrfs: add helper to calculate space for delayed references

Instead of duplicating the logic for calculating how much space is
required for a given number of delayed references, add an inline helper
to encapsulate that logic and use it everywhere we are calculating the
space required.

Reviewed-by: Josef Bacik <josef@toxicpanda.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, 1 insertions, 13 deletions

diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c
index a2e14c410416..75e7fa337e66 100644
--- a/fs/btrfs/space-info.c
+++ b/fs/btrfs/space-info.c
@@ -553,21 +553,9 @@ static inline u64 calc_reclaim_items_nr(const struct btrfs_fs_info *fs_info,
 static inline u64 calc_delayed_refs_nr(const struct btrfs_fs_info *fs_info,
 				       u64 to_reclaim)
 {
-	u64 bytes;
+	const u64 bytes = btrfs_calc_delayed_ref_bytes(fs_info, 1);
 	u64 nr;
 
-	bytes = btrfs_calc_insert_metadata_size(fs_info, 1);
-	/*
-	 * We have to check the mount option here because we could be enabling
-	 * the free space tree for the first time and don't have the compat_ro
-	 * option set yet.
-	 *
-	 * We need extra reservations if we have the free space tree because
-	 * we'll have to modify that tree as well.
-	 */
-	if (btrfs_test_opt(fs_info, FREE_SPACE_TREE))
-		bytes *= 2;
-
 	nr = div64_u64(to_reclaim, bytes);
 	if (!nr)
 		nr = 1;