diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 974687808153..37c4da3403d0 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -3359,9 +3359,8 @@ int __must_check btrfs_update_root(struct btrfs_trans_handle *trans,
 				   struct btrfs_root *root,
 				   struct btrfs_key *key,
 				   struct btrfs_root_item *item);
-void btrfs_read_root_item(struct btrfs_root *root,
-			 struct extent_buffer *eb, int slot,
-			 struct btrfs_root_item *item);
+void btrfs_read_root_item(struct extent_buffer *eb, int slot,
+			  struct btrfs_root_item *item);
 int btrfs_find_last_root(struct btrfs_root *root, u64 objectid, struct
 			 btrfs_root_item *item, struct btrfs_key *key);
 int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 84c4fa503ef5..a03a96650548 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1481,7 +1481,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
 	if (ret == 0) {
 		l = path->nodes[0];
 		slot = path->slots[0];
-		btrfs_read_root_item(tree_root, l, slot, &root->root_item);
+		btrfs_read_root_item(l, slot, &root->root_item);
 		memcpy(&root->root_key, location, sizeof(*location));
 	}
 	btrfs_free_path(path);
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 668af537a3ea..5bf1ed57f178 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -29,9 +29,8 @@
  * generation numbers as then we know the root was once mounted with an older
  * kernel that was not aware of the root item structure change.
  */
-void btrfs_read_root_item(struct btrfs_root *root,
-			 struct extent_buffer *eb, int slot,
-			 struct btrfs_root_item *item)
+void btrfs_read_root_item(struct extent_buffer *eb, int slot,
+			  struct btrfs_root_item *item)
 {
 	uuid_le uuid;
 	int len;
@@ -104,7 +103,7 @@ int btrfs_find_last_root(struct btrfs_root *root, u64 objectid,
 		goto out;
 	}
 	if (item)
-		btrfs_read_root_item(root, l, slot, item);
+		btrfs_read_root_item(l, slot, item);
 	if (key)
 		memcpy(key, &found_key, sizeof(found_key));