Btrfs: creating the subvolume qgroup automatically when enabling quota

Creating the subvolume/snapshots(including root subvolume) qgroup
auotomatically when enabling quota.

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

1 files changed, 55 insertions, 0 deletions

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 33b0bea50b45..5be5a39dedc4 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -781,11 +781,15 @@ int btrfs_quota_enable(struct btrfs_trans_handle *trans,
                        struct btrfs_fs_info *fs_info)
 {
         struct btrfs_root *quota_root;
+        struct btrfs_root *tree_root = fs_info->tree_root;
         struct btrfs_path *path = NULL;
         struct btrfs_qgroup_status_item *ptr;
         struct extent_buffer *leaf;
         struct btrfs_key key;
+        struct btrfs_key found_key;
+        struct btrfs_qgroup *qgroup = NULL;
         int ret = 0;
+        int slot;
 
         spin_lock(&fs_info->qgroup_lock);
         if (fs_info->quota_root) {
@@ -832,7 +836,58 @@ int btrfs_quota_enable(struct btrfs_trans_handle *trans,
 
         btrfs_mark_buffer_dirty(leaf);
 
+        key.objectid = 0;
+        key.type = BTRFS_ROOT_REF_KEY;
+        key.offset = 0;
+
+        btrfs_release_path(path);
+        ret = btrfs_search_slot_for_read(tree_root, &key, path, 1, 0);
+        if (ret > 0)
+                goto out_add_root;
+        if (ret < 0)
+                goto out_free_path;
+
+
+        while (1) {
+                slot = path->slots[0];
+                leaf = path->nodes[0];
+                btrfs_item_key_to_cpu(leaf, &found_key, slot);
+
+                if (found_key.type == BTRFS_ROOT_REF_KEY) {
+                        ret = add_qgroup_item(trans, quota_root,
+                                              found_key.offset);
+                        if (ret)
+                                goto out_free_path;
+
+                        spin_lock(&fs_info->qgroup_lock);
+                        qgroup = add_qgroup_rb(fs_info, found_key.offset);
+                        if (IS_ERR(qgroup)) {
+                                spin_unlock(&fs_info->qgroup_lock);
+                                ret = PTR_ERR(qgroup);
+                                goto out_free_path;
+                        }
+                        spin_unlock(&fs_info->qgroup_lock);
+                }
+                ret = btrfs_next_item(tree_root, path);
+                if (ret < 0)
+                        goto out_free_path;
+                if (ret)
+                        break;
+        }
+
+out_add_root:
+        btrfs_release_path(path);
+        ret = add_qgroup_item(trans, quota_root, BTRFS_FS_TREE_OBJECTID);
+        if (ret)
+                goto out_free_path;
+
         spin_lock(&fs_info->qgroup_lock);
+        qgroup = add_qgroup_rb(fs_info, BTRFS_FS_TREE_OBJECTID);
+        if (IS_ERR(qgroup)) {
+                spin_unlock(&fs_info->qgroup_lock);
+                ret = PTR_ERR(qgroup);
+                goto out_free_path;
+        }
         fs_info->quota_root = quota_root;
         fs_info->pending_quota_state = 1;
         spin_unlock(&fs_info->qgroup_lock);