btrfs: delayed-inode: Remove wrong qgroup meta reservation calls

Commit 4f5427ccce5d ("btrfs: delayed-inode: Use new qgroup meta rsv for
delayed inode and item") merged into mainline was not latest version
submitted to the mail list in Dec 2017.

Which lacks the following fixes:

1) Remove btrfs_qgroup_convert_reserved_meta() call in
   btrfs_delayed_item_release_metadata()
2) Remove btrfs_qgroup_reserve_meta_prealloc() call in
   btrfs_delayed_inode_reserve_metadata()

Those fixes will resolve unexpected EDQUOT problems.

Fixes: 4f5427ccce5d ("btrfs: delayed-inode: Use new qgroup meta rsv for delayed inode and item")
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/delayed-inode.c

@@ -556,6 +556,12 @@ static int btrfs_delayed_item_reserve_metadata(struct btrfs_trans_handle *trans,
 	dst_rsv = &fs_info->delayed_block_rsv;
 
 	num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
+
+	/*
+	 * Here we migrate space rsv from transaction rsv, since have already
+	 * reserved space when starting a transaction.  So no need to reserve
+	 * qgroup space here.
+	 */
 	ret = btrfs_block_rsv_migrate(src_rsv, dst_rsv, num_bytes, 1);
 	if (!ret) {
 		trace_btrfs_space_reservation(fs_info, "delayed_item",
@@ -577,7 +583,10 @@ static void btrfs_delayed_item_release_metadata(struct btrfs_root *root,
 		return;
 
 	rsv = &fs_info->delayed_block_rsv;
-	btrfs_qgroup_convert_reserved_meta(root, item->bytes_reserved);
+	/*
+	 * Check btrfs_delayed_item_reserve_metadata() to see why we don't need
+	 * to release/reserve qgroup space.
+	 */
 	trace_btrfs_space_reservation(fs_info, "delayed_item",
 				      item->key.objectid, item->bytes_reserved,
 				      0);
@@ -602,9 +611,6 @@ static int btrfs_delayed_inode_reserve_metadata(
 
 	num_bytes = btrfs_calc_trans_metadata_size(fs_info, 1);
 
-	ret = btrfs_qgroup_reserve_meta_prealloc(root, num_bytes, true);
-	if (ret < 0)
-		return ret;
 	/*
 	 * btrfs_dirty_inode will update the inode under btrfs_join_transaction
 	 * which doesn't reserve space for speed.  This is a problem since we
@@ -616,6 +622,10 @@ static int btrfs_delayed_inode_reserve_metadata(
 	 */
 	if (!src_rsv || (!trans->bytes_reserved &&
 			 src_rsv->type != BTRFS_BLOCK_RSV_DELALLOC)) {
+		ret = btrfs_qgroup_reserve_meta_prealloc(root,
+				fs_info->nodesize, true);
+		if (ret < 0)
+			return ret;
 		ret = btrfs_block_rsv_add(root, dst_rsv, num_bytes,
 					  BTRFS_RESERVE_NO_FLUSH);
 		/*
@@ -634,6 +644,8 @@ static int btrfs_delayed_inode_reserve_metadata(
 						      "delayed_inode",
 						      btrfs_ino(inode),
 						      num_bytes, 1);
+		} else {
+			btrfs_qgroup_free_meta_prealloc(root, fs_info->nodesize);
 		}
 		return ret;
 	}