btrfs: Move may_destroy_subvol() from ioctl.c to inode.c

This is a preparation work to refactor btrfs_ioctl_snap_destroy()
and to allow rmdir(2) to delete an empty subvolume.

Signed-off-by: Tomohiro Misono <misono.tomohiro@jp.fujitsu.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ minor update of the function comment ]
Signed-off-by: David Sterba <dsterba@suse.com>

1 files changed, 0 insertions, 54 deletions

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 61a58214681c..592ef10a6604 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1832,60 +1832,6 @@ out:
 	return ret;
 }
 
-/*
- * helper to check if the subvolume references other subvolumes
- */
-static noinline int may_destroy_subvol(struct btrfs_root *root)
-{
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_path *path;
-	struct btrfs_dir_item *di;
-	struct btrfs_key key;
-	u64 dir_id;
-	int ret;
-
-	path = btrfs_alloc_path();
-	if (!path)
-		return -ENOMEM;
-
-	/* Make sure this root isn't set as the default subvol */
-	dir_id = btrfs_super_root_dir(fs_info->super_copy);
-	di = btrfs_lookup_dir_item(NULL, fs_info->tree_root, path,
-				   dir_id, "default", 7, 0);
-	if (di && !IS_ERR(di)) {
-		btrfs_dir_item_key_to_cpu(path->nodes[0], di, &key);
-		if (key.objectid == root->root_key.objectid) {
-			ret = -EPERM;
-			btrfs_err(fs_info,
-				  "deleting default subvolume %llu is not allowed",
-				  key.objectid);
-			goto out;
-		}
-		btrfs_release_path(path);
-	}
-
-	key.objectid = root->root_key.objectid;
-	key.type = BTRFS_ROOT_REF_KEY;
-	key.offset = (u64)-1;
-
-	ret = btrfs_search_slot(NULL, fs_info->tree_root, &key, path, 0, 0);
-	if (ret < 0)
-		goto out;
-	BUG_ON(ret == 0);
-
-	ret = 0;
-	if (path->slots[0] > 0) {
-		path->slots[0]--;
-		btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
-		if (key.objectid == root->root_key.objectid &&
-		    key.type == BTRFS_ROOT_REF_KEY)
-			ret = -ENOTEMPTY;
-	}
-out:
-	btrfs_free_path(path);
-	return ret;
-}
-
 static noinline int key_in_sk(struct btrfs_key *key,
 			      struct btrfs_ioctl_search_key *sk)
 {