btrfs: use rb_find() in find_qgroup_rb()

Use the rb-tree helper so we don't open code the search code.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Signed-off-by: Pan Chuang <panchuang@vivo.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index b3176edbde82a0c2027553c014c68d119dbc7ceb..2e2a76c3e92a9c3781681fbf828c1fde8b3f5246 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -160,23 +160,27 @@ qgroup_rescan_init(struct btrfs_fs_info *fs_info, u64 progress_objectid,
                   int init_flags);
 static void qgroup_rescan_zero_tracking(struct btrfs_fs_info *fs_info);
 
+static int btrfs_qgroup_qgroupid_key_cmp(const void *key, const struct rb_node *node)
+{
+       const u64 *qgroupid = key;
+       const struct btrfs_qgroup *qgroup = rb_entry(node, struct btrfs_qgroup, node);
+
+       if (qgroup->qgroupid < *qgroupid)
+               return -1;
+       else if (qgroup->qgroupid > *qgroupid)
+               return 1;
+
+       return 0;
+}
+
 /* must be called with qgroup_ioctl_lock held */
 static struct btrfs_qgroup *find_qgroup_rb(const struct btrfs_fs_info *fs_info,
                                           u64 qgroupid)
 {
-       struct rb_node *n = fs_info->qgroup_tree.rb_node;
-       struct btrfs_qgroup *qgroup;
+       struct rb_node *node;
 
-       while (n) {
-               qgroup = rb_entry(n, struct btrfs_qgroup, node);
-               if (qgroup->qgroupid < qgroupid)
-                       n = n->rb_left;
-               else if (qgroup->qgroupid > qgroupid)
-                       n = n->rb_right;
-               else
-                       return qgroup;
-       }
-       return NULL;
+       node = rb_find(&qgroupid, &fs_info->qgroup_tree, btrfs_qgroup_qgroupid_key_cmp);
+       return rb_entry_safe(node, struct btrfs_qgroup, node);
 }
 
 /*