From 3444a97255de907f32562741fb6d104620b9fce3 Mon Sep 17 00:00:00 2001 From: Jeff Mahoney Date: Mon, 3 Oct 2011 23:23:13 -0400 Subject: [PATCH] btrfs: Factor out tree->ops->merge_bio_hook call In submit_extent_page, there's a visually noisy if statement that, in the midst of other conditions, does the tree dependency for tree->ops and tree->ops->merge_bio_hook before calling it, and then another condition afterwards. If an error is returned from merge_bio_hook, there's no way to catch it. It's considered a routine "1" return value instead of a failure. This patch factors out the dependency check into a new local merge_bio routine and BUG's on an error. The if statement is less noisy as a side- effect. Signed-off-by: Jeff Mahoney --- fs/btrfs/extent_io.c | 17 ++++++++++++++--- fs/btrfs/inode.c | 5 +++-- 2 files changed, 17 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index a4a7a18..c342e92 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2429,6 +2429,19 @@ static int submit_one_bio(int rw, struct bio *bio, int mirror_num, return ret; } +static int merge_bio(struct extent_io_tree *tree, struct page *page, + unsigned long offset, size_t size, struct bio *bio, + unsigned long bio_flags) +{ + int ret = 0; + if (tree->ops && tree->ops->merge_bio_hook) + ret = tree->ops->merge_bio_hook(page, offset, size, bio, + bio_flags); + BUG_ON(ret < 0); + return ret; + +} + static int submit_extent_page(int rw, struct extent_io_tree *tree, struct page *page, sector_t sector, size_t size, unsigned long offset, @@ -2457,9 +2470,7 @@ static int submit_extent_page(int rw, struct extent_io_tree *tree, sector; if (prev_bio_flags != bio_flags || !contig || - (tree->ops && tree->ops->merge_bio_hook && - tree->ops->merge_bio_hook(page, offset, page_size, bio, - bio_flags)) || + merge_bio(tree, page, offset, page_size, bio, bio_flags) || bio_add_page(bio, page, page_size, offset) < page_size) { ret = submit_one_bio(rw, bio, mirror_num, prev_bio_flags); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index f0dfd7d..ad1e88d 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1425,10 +1425,11 @@ int btrfs_merge_bio_hook(struct page *page, unsigned long offset, map_length = length; ret = btrfs_map_block(map_tree, READ, logical, &map_length, NULL, 0); - + /* Will always return 0 or 1 with map_multi == NULL */ + BUG_ON(ret < 0); if (map_length < length + size) return 1; - return ret; + return 0; } /* -- 2.7.4