diff options
| author | Ming Lei <ming.lei@canonical.com> | 2016-02-26 23:40:51 +0800 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2016-03-03 14:42:49 -0700 |
| commit | e0af29171aa8912e1ca95023b75ef336cd70d661 (patch) | |
| tree | 0e8bd6fdfb2b96eb505f71f306afbab72d4f3c88 | |
| parent | 7bcd79ac50d9d83350a835bdb91c04ac9e098412 (diff) | |
| download | kvm-e0af29171aa8912e1ca95023b75ef336cd70d661.tar.gz | |
block: check virt boundary in bio_will_gap()
In the following patch, the way for figuring out
the last bvec will be changed with a bit cost introduced,
so return immediately if the queue doesn't have virt
boundary limit. Actually most of devices have not
this limit.
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
| -rw-r--r-- | include/linux/blkdev.h | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 4571ef1a12a968..cd06a41581b321 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1372,6 +1372,13 @@ static inline void put_dev_sector(Sector p) page_cache_release(p.v); } +static inline bool __bvec_gap_to_prev(struct request_queue *q, + struct bio_vec *bprv, unsigned int offset) +{ + return offset || + ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); +} + /* * Check if adding a bio_vec after bprv with offset would create a gap in * the SG list. Most drivers don't care about this, but some do. @@ -1381,18 +1388,17 @@ static inline bool bvec_gap_to_prev(struct request_queue *q, { if (!queue_virt_boundary(q)) return false; - return offset || - ((bprv->bv_offset + bprv->bv_len) & queue_virt_boundary(q)); + return __bvec_gap_to_prev(q, bprv, offset); } static inline bool bio_will_gap(struct request_queue *q, struct bio *prev, struct bio *next) { - if (!bio_has_data(prev)) + if (!bio_has_data(prev) || !queue_virt_boundary(q)) return false; - return bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1], - next->bi_io_vec[0].bv_offset); + return __bvec_gap_to_prev(q, &prev->bi_io_vec[prev->bi_vcnt - 1], + next->bi_io_vec[0].bv_offset); } static inline bool req_gap_back_merge(struct request *req, struct bio *bio) |