Commit 73383adf authored by Sagi Grimberg's avatar Sagi Grimberg Committed by Christoph Hellwig
Browse files

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: default avatarSagi Grimberg <sagi@grimberg.me>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 783f4a44

drivers/nvme/target/io-cmd-bdev.c

+7 −2
Original line number Diff line number Diff line
@@ -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);



	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;

drivers/nvme/target/nvmet.h

+1 −0
Original line number Diff line number Diff line
@@ -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;

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