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>

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 9c44d65..4fc9751 100644 (file)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -3697,6 +3697,7 @@ static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
                goto drop_write;
        }
 
+       down_write(&root->fs_info->subvol_sem);
        if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
                trans = btrfs_start_transaction(root, 2);
                if (IS_ERR(trans)) {
@@ -3730,6 +3731,7 @@ static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
        }
 out:
        kfree(sa);
+       up_write(&root->fs_info->subvol_sem);
 drop_write:
        mnt_drop_write_file(file);
        return ret;

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 33b0bea..5be5a39 100644 (file)
--- 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);