Btrfs: reada while dropping snapshots (e011599b) · Commits · e / devices / android_kernel_teracube_emerald

fs/btrfs/extent-tree.c

+30 −1

Original line number	Diff line number	Diff line
		@@ -940,7 +940,6 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		int wrapped = 0;
		u64 limit;

		path = btrfs_alloc_path();
		ins->flags = 0;
		btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);

		@@ -974,6 +973,8 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
		data, 1);
		}

		path = btrfs_alloc_path();

		check_failed:
		if (!block_group->data)
		search_start = find_search_start(root, &block_group,
		@@ -1355,6 +1356,28 @@ static int drop_leaf_ref(struct btrfs_trans_handle *trans,
		return 0;
		}

		static void reada_walk_down(struct btrfs_root *root,
		struct btrfs_node *node)
		{
		int i;
		u32 nritems;
		u64 blocknr;
		int ret;
		u32 refs;

		nritems = btrfs_header_nritems(&node->header);
		for (i = 0; i < nritems; i++) {
		blocknr = btrfs_node_blockptr(node, i);
		ret = lookup_extent_ref(NULL, root, blocknr, 1, &refs);
		BUG_ON(ret);
		if (refs != 1)
		continue;
		ret = readahead_tree_block(root, blocknr);
		if (ret)
		break;
		}
		}

		/*
		* helper function for drop_snapshot, this walks down the tree dropping ref
		* counts as it goes.
		@@ -1375,6 +1398,7 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root
		BUG_ON(ret);
		if (refs > 1)
		goto out;

		/*
		* walk down to the last node level and free all the leaves
		*/
		@@ -1382,8 +1406,13 @@ static int walk_down_tree(struct btrfs_trans_handle *trans, struct btrfs_root
		WARN_ON(*level < 0);
		WARN_ON(*level >= BTRFS_MAX_LEVEL);
		cur = path->nodes[*level];

		if (level > 0 && path->slots[level] == 0)
		reada_walk_down(root, btrfs_buffer_node(cur));

		if (btrfs_header_level(btrfs_buffer_header(cur)) != *level)
		WARN_ON(1);

		if (path->slots[*level] >=
		btrfs_header_nritems(btrfs_buffer_header(cur)))
		break;