btrfs: Remove unnecessary variants in relocation.c

These arguments are not used in functions, remove them for cleanup
and make kernel stack happy.

Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>

fs/btrfs/ctree.h

@@ -4185,8 +4185,7 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len);
 int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
 			  struct btrfs_root *root, struct extent_buffer *buf,
 			  struct extent_buffer *cow);
-void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans,
-			      struct btrfs_pending_snapshot *pending,
+void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending,
 			      u64 *bytes_to_reserve);
 int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
 			      struct btrfs_pending_snapshot *pending);

fs/btrfs/relocation.c

@@ -2523,8 +2523,7 @@ struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans,
  * counted. return -ENOENT if the block is root of reloc tree.
  */
 static noinline_for_stack
-struct btrfs_root *select_one_root(struct btrfs_trans_handle *trans,
-				   struct backref_node *node)
+struct btrfs_root *select_one_root(struct backref_node *node)
 {
 	struct backref_node *next;
 	struct btrfs_root *root;
@@ -2912,7 +2911,7 @@ static int relocate_tree_block(struct btrfs_trans_handle *trans,
 		return 0;
 
 	BUG_ON(node->processed);
-	root = select_one_root(trans, node);
+	root = select_one_root(node);
 	if (root == ERR_PTR(-ENOENT)) {
 		update_processed_blocks(rc, node);
 		goto out;
@@ -3755,8 +3754,7 @@ out:
  * helper to find next unprocessed extent
  */
 static noinline_for_stack
-int find_next_extent(struct btrfs_trans_handle *trans,
-		     struct reloc_control *rc, struct btrfs_path *path,
+int find_next_extent(struct reloc_control *rc, struct btrfs_path *path,
 		     struct btrfs_key *extent_key)
 {
 	struct btrfs_key key;
@@ -3951,7 +3949,7 @@ restart:
 			continue;
 		}
 
-		ret = find_next_extent(trans, rc, path, &key);
+		ret = find_next_extent(rc, path, &key);
 		if (ret < 0)
 			err = ret;
 		if (ret != 0)
@@ -4596,8 +4594,7 @@ int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
  * called before creating snapshot. it calculates metadata reservation
  * requried for relocating tree blocks in the snapshot
  */
-void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans,
-			      struct btrfs_pending_snapshot *pending,
+void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending,
 			      u64 *bytes_to_reserve)
 {
 	struct btrfs_root *root;

fs/btrfs/transaction.c

@@ -1301,7 +1301,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
 	 */
 	btrfs_set_skip_qgroup(trans, objectid);
 
-	btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
+	btrfs_reloc_pre_snapshot(pending, &to_reserve);
 
 	if (to_reserve > 0) {
 		pending->error = btrfs_block_rsv_add(root,