From 73383adfad245bb84e6d6ef7830f01048fcfc217 Mon Sep 17 00:00:00 2001 From: Sagi Grimberg Date: Fri, 28 Sep 2018 15:40:43 -0700 Subject: [PATCH] nvmet: don't split large I/Os unconditionally If we know that the I/O size exceeds our inline bio vec, no point using it and split the rest to begin with. We could in theory reuse the inline bio and only allocate the bio_vec, but its really not worth optimizing for. Signed-off-by: Sagi Grimberg Signed-off-by: Christoph Hellwig --- drivers/nvme/target/io-cmd-bdev.c | 9 +++++++-- drivers/nvme/target/nvmet.h | 1 + 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c index 7bc9f6240432..f93fb5711142 100644 --- a/drivers/nvme/target/io-cmd-bdev.c +++ b/drivers/nvme/target/io-cmd-bdev.c @@ -58,7 +58,7 @@ static void nvmet_bio_done(struct bio *bio) static void nvmet_bdev_execute_rw(struct nvmet_req *req) { int sg_cnt = req->sg_cnt; - struct bio *bio = &req->b.inline_bio; + struct bio *bio; struct scatterlist *sg; sector_t sector; blk_qc_t cookie; @@ -81,7 +81,12 @@ static void nvmet_bdev_execute_rw(struct nvmet_req *req) sector = le64_to_cpu(req->cmd->rw.slba); sector <<= (req->ns->blksize_shift - 9); - bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec)); + if (req->data_len <= NVMET_MAX_INLINE_DATA_LEN) { + bio = &req->b.inline_bio; + bio_init(bio, req->inline_bvec, ARRAY_SIZE(req->inline_bvec)); + } else { + bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES)); + } bio_set_dev(bio, req->ns->bdev); bio->bi_iter.bi_sector = sector; bio->bi_private = req; diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h index ec9af4ee03b6..08f7b57a1203 100644 --- a/drivers/nvme/target/nvmet.h +++ b/drivers/nvme/target/nvmet.h @@ -264,6 +264,7 @@ struct nvmet_fabrics_ops { }; #define NVMET_MAX_INLINE_BIOVEC 8 +#define NVMET_MAX_INLINE_DATA_LEN NVMET_MAX_INLINE_BIOVEC * PAGE_SIZE struct nvmet_req { struct nvme_command *cmd; -- 2.11.0