Commit 4eb150d6 authored by Qu Wenruo's avatar Qu Wenruo Committed by David Sterba
Browse files

btrfs: unify the error handling pattern for read_tree_block() 



We had an error handling pattern for read_tree_block() like this:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 * Normally ended up with return or goto out.
		 */
	} else if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 * Normally also ended up with return or goto out;
		 */
	}

This is fine, but if we want to add extra check for each
read_tree_block(), the existing if-else-if is not that expandable and
will take reader some seconds to figure out there is no extra branch.

Here we change it to a more common way, without the extra else:

	eb = read_tree_block();
	if (IS_ERR(eb)) {
		/*
		 * Handling error here
		 */
		return eb or goto out;
	}
	if (!extent_buffer_uptodate(eb)) {
		/*
		 * Different error handling here
		 */
		return eb or goto out;
	}

This also removes some oddball call sites which uses some creative way
to check error.

Signed-off-by: default avatarQu Wenruo <wqu@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 8f8aa4c7

fs/btrfs/backref.c

+5 −2
Original line number Diff line number Diff line
@@ -789,11 +789,13 @@ static int add_missing_keys(struct btrfs_fs_info *fs_info, 
		if (IS_ERR(eb)) {

			free_pref(ref);

			return PTR_ERR(eb);

		} else if (!extent_buffer_uptodate(eb)) {

		}

		if (!extent_buffer_uptodate(eb)) {

			free_pref(ref);

			free_extent_buffer(eb);

			return -EIO;

		}



		if (lock)

			btrfs_tree_read_lock(eb);

		if (btrfs_header_level(eb) == 0)
@@ -1335,7 +1337,8 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans, 
				if (IS_ERR(eb)) {

					ret = PTR_ERR(eb);

					goto out;

				} else if (!extent_buffer_uptodate(eb)) {

				}

				if (!extent_buffer_uptodate(eb)) {

					free_extent_buffer(eb);

					ret = -EIO;

					goto out;

fs/btrfs/ctree.c

+16 −14
Original line number Diff line number Diff line
@@ -846,9 +846,11 @@ struct extent_buffer *btrfs_read_node_slot(struct extent_buffer *parent, 
			     btrfs_header_owner(parent),

			     btrfs_node_ptr_generation(parent, slot),

			     level - 1, &first_key);

	if (!IS_ERR(eb) && !extent_buffer_uptodate(eb)) {

	if (IS_ERR(eb))

		return eb;

	if (!extent_buffer_uptodate(eb)) {

		free_extent_buffer(eb);

		eb = ERR_PTR(-EIO);

		return ERR_PTR(-EIO);

	}



	return eb;
@@ -1460,7 +1462,10 @@ read_block_for_search(struct btrfs_root *root, struct btrfs_path *p, 
	ret = -EAGAIN;

	tmp = read_tree_block(fs_info, blocknr, root->root_key.objectid,

			      gen, parent_level - 1, &first_key);

	if (!IS_ERR(tmp)) {

	if (IS_ERR(tmp)) {

		btrfs_release_path(p);

		return PTR_ERR(tmp);

	}

	/*

	 * If the read above didn't mark this buffer up to date,

	 * it will never end up being up to date.  Set ret to EIO now
@@ -1470,9 +1475,6 @@ read_block_for_search(struct btrfs_root *root, struct btrfs_path *p, 
	if (!extent_buffer_uptodate(tmp))

		ret = -EIO;

	free_extent_buffer(tmp);

	} else {

		ret = PTR_ERR(tmp);

	}



	btrfs_release_path(p);

	return ret;

fs/btrfs/disk-io.c

+9 −7
Original line number Diff line number Diff line
@@ -1543,7 +1543,8 @@ static struct btrfs_root *read_tree_root_path(struct btrfs_root *tree_root, 
		ret = PTR_ERR(root->node);

		root->node = NULL;

		goto fail;

	} else if (!btrfs_buffer_uptodate(root->node, generation, 0)) {

	}

	if (!btrfs_buffer_uptodate(root->node, generation, 0)) {

		ret = -EIO;

		goto fail;

	}
@@ -2537,11 +2538,13 @@ static int btrfs_replay_log(struct btrfs_fs_info *fs_info, 
		log_tree_root->node = NULL;

		btrfs_put_root(log_tree_root);

		return ret;

	} else if (!extent_buffer_uptodate(log_tree_root->node)) {

	}

	if (!extent_buffer_uptodate(log_tree_root->node)) {

		btrfs_err(fs_info, "failed to read log tree");

		btrfs_put_root(log_tree_root);

		return -EIO;

	}



	/* returns with log_tree_root freed on success */

	ret = btrfs_recover_log_trees(log_tree_root);

	if (ret) {
@@ -2983,15 +2986,14 @@ static int load_super_root(struct btrfs_root *root, u64 bytenr, u64 gen, int lev 
	if (IS_ERR(root->node)) {

		ret = PTR_ERR(root->node);

		root->node = NULL;

	} else if (!extent_buffer_uptodate(root->node)) {

		return ret;

	}

	if (!extent_buffer_uptodate(root->node)) {

		free_extent_buffer(root->node);

		root->node = NULL;

		ret = -EIO;

		return -EIO;

	}



	if (ret)

		return ret;



	btrfs_set_root_node(&root->root_item, root->node);

	root->commit_root = btrfs_root_node(root);

	btrfs_set_root_refs(&root->root_item, 1);

fs/btrfs/print-tree.c

+2 −2
Original line number Diff line number Diff line
@@ -392,9 +392,9 @@ void btrfs_print_tree(struct extent_buffer *c, bool follow) 
				       btrfs_header_owner(c),

				       btrfs_node_ptr_generation(c, i),

				       level - 1, &first_key);

		if (IS_ERR(next)) {

		if (IS_ERR(next))

			continue;

		} else if (!extent_buffer_uptodate(next)) {

		if (!extent_buffer_uptodate(next)) {

			free_extent_buffer(next);

			continue;

		}

fs/btrfs/relocation.c

+2 −2
Original line number Diff line number Diff line
@@ -2599,9 +2599,9 @@ static int get_tree_block_key(struct btrfs_fs_info *fs_info, 


	eb = read_tree_block(fs_info, block->bytenr, block->owner,

			     block->key.offset, block->level, NULL);

	if (IS_ERR(eb)) {

	if (IS_ERR(eb))

		return PTR_ERR(eb);

	} else if (!extent_buffer_uptodate(eb)) {

	if (!extent_buffer_uptodate(eb)) {

		free_extent_buffer(eb);

		return -EIO;

	}