Btrfs: fix missing deleted items in btrfs_clean_quota_tree

Steps to reproduce:

	i=0
	ncases=100

	mkfs.btrfs <disk>
	mount <disk> <mnt>
	btrfs quota enable <mnt>
	btrfs qgroup create 2/1 <mnt>
	while [ $i -le $ncases ]
	do
		btrfs qgroup create 1/$i <mnt>
		btrfs qgroup assign 1/$i 2/1 <mnt>
		i=$(($i+1))
	done

	btrfs quota disable <mnt>
	umount <mnt>
	btrfsck <mnt>

You can also use the commands:
	btrfs-debug-tree <disk> | grep QGROUP

You will find there are still items existed.The reasons why this happens
is because the original code just checks slots[0]==0 and returns.
We try to fix it by deleting the leaf one by one.

Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 88ab785bbd73181e64843d97838799619e1c140e..f011d9b8ffb1fbe66715fc2dd281434f8d716c4f 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -732,7 +732,9 @@ static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
 {
        struct btrfs_path *path;
        struct btrfs_key key;
+       struct extent_buffer *leaf = NULL;
        int ret;
+       int nr = 0;
 
        if (!root)
                return -EINVAL;
@@ -741,24 +743,30 @@ static int btrfs_clean_quota_tree(struct btrfs_trans_handle *trans,
        if (!path)
                return -ENOMEM;
 
-       while (1) {
-               key.objectid = 0;
-               key.offset = 0;
-               key.type = 0;
+       path->leave_spinning = 1;
 
-               path->leave_spinning = 1;
+       key.objectid = 0;
+       key.offset = 0;
+       key.type = 0;
+
+       while (1) {
                ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
-               if (ret > 0) {
-                       if (path->slots[0] == 0)
-                               break;
-                       path->slots[0]--;
-               } else if (ret < 0) {
+               if (ret < 0)
+                       goto out;
+               leaf = path->nodes[0];
+               nr = btrfs_header_nritems(leaf);
+               if (!nr)
                        break;
-               }
-
-               ret = btrfs_del_item(trans, root, path);
+               /*
+                * delete the leaf one by one
+                * since the whole tree is going
+                * to be deleted.
+                */
+               path->slots[0] = 0;
+               ret = btrfs_del_items(trans, root, path, 0, nr);
                if (ret)
                        goto out;
+
                btrfs_release_path(path);
        }
        ret = 0;