This patch pulls the trigger for multipage bvecs. Any request queue which doesn't set QUEUE_FLAG_NO_MP should support to handle multipage bvecs.
Signed-off-by: Ming Lei <[email protected]> --- block/bio.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/block/bio.c b/block/bio.c index 9acc3db0f2df..a2ad9c577aff 100644 --- a/block/bio.c +++ b/block/bio.c @@ -843,6 +843,11 @@ int bio_add_page(struct bio *bio, struct page *page, * a consecutive offset. Optimize this special case. */ if (bio->bi_vcnt > 0) { + struct request_queue *q = NULL; + + if (bio->bi_bdev) + q = bdev_get_queue(bio->bi_bdev); + bv = &bio->bi_io_vec[bio->bi_vcnt - 1]; if (page == bv->bv_page && @@ -850,6 +855,14 @@ int bio_add_page(struct bio *bio, struct page *page, bv->bv_len += len; goto done; } + + /* disable multipage bvec too if cluster isn't enabled */ + if (q && !blk_queue_no_mp(q) && blk_queue_cluster(q) && + (bvec_to_phys(bv) + bv->bv_len == + page_to_phys(page) + offset)) { + bv->bv_len += len; + goto done; + } } if (bio->bi_vcnt >= bio->bi_max_vecs) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
