[dm-devel] [PATCH 11/17] btrfs: make dec_and_test_compressed_bio() to be split bio compatible

[Qu Wenruo]

For compression read write endio functions, they all rely on
dec_and_test_compressed_bio() to determine if they are the last bio.

So here we only need to convert the bio_for_each_segment_all() call into
__bio_for_each_segment() so that compression read/write endio functions
will handle both split and unsplit bios well.

Signed-off-by: Qu Wenruo <wqu at suse.com>
---
 fs/btrfs/compression.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 8668c5190805..8b4b84b59b0c 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -205,18 +205,14 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct bio *bio,
 static bool dec_and_test_compressed_bio(struct compressed_bio *cb, struct bio *bio)
 {
 	struct btrfs_fs_info *fs_info = btrfs_sb(cb->inode->i_sb);
+	struct bio_vec bvec;
+	struct bvec_iter iter;
 	unsigned int bi_size = 0;
 	bool last_io = false;
-	struct bio_vec *bvec;
-	struct bvec_iter_all iter_all;
 
-	/*
-	 * At endio time, bi_iter.bi_size doesn't represent the real bio size.
-	 * Thus here we have to iterate through all segments to grab correct
-	 * bio size.
-	 */
-	bio_for_each_segment_all(bvec, bio, iter_all)
-		bi_size += bvec->bv_len;
+	ASSERT(btrfs_bio(bio)->iter.bi_size);
+	__bio_for_each_segment(bvec, bio, iter, btrfs_bio(bio)->iter)
+		bi_size += bvec.bv_len;
 
 	if (bio->bi_status)
 		cb->errors = 1;
-- 
2.34.1