[PATCH v1 3/4] block: get the 1st and last bvec via helpers

Ming Lei
2016-02-19T03:21:21Z

This patch applies the two introduced helpers to
figure out the 1st and last bvec, and fixes the
original way after bio splitting.

Cc: stable@vger.kernel.org
Reported-by: Sagi Grimberg <sagig@dev.mellanox.co.il>
Cc: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
include/linux/blkdev.h | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 5023401..de4fc002 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1394,11 +1394,16 @@ static inline bool bvec_gap_to_prev(struct request_queue *q,
static inline bool bio_will_gap(struct request_queue *q, struct bio *prev,
struct bio *next)
{
- if (!bio_has_data(prev) || !queue_virt_boundary(q))
+ if (!bio_has_data(prev) || !queue_virt_boundary(q)) {
return false;
+ } else {
+ struct bio_vec pb, nb;

- return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1],
- next->bi_io_vec[0].bv_offset);
+ bio_get_last_bvec(prev, &pb);
+ bio_get_first_bvec(next, &nb);
+
+ return __bvec_gap_to_prev(q, &pb, nb.bv_offset);
+ }
}

static inline bool req_gap_back_merge(struct request *req, struct bio *bio)
--
1.9.1