diff options
| author | Logan Gunthorpe | 2020-10-16 16:19:05 -0600 |
|---|---|---|
| committer | Christoph Hellwig | 2020-10-22 15:28:02 +0200 |
| commit | 5e063101ffacf7c14797f5185c58a967ca83c79f (patch) | |
| tree | 9dd5d8300c7ec5af92fe15492027363d6ed7f370 | |
| parent | df06047d54276f73782c9d97882b305fca745d3f (diff) | |
nvmet: cleanup nvmet_passthru_map_sg()
Clean up some confusing elements of nvmet_passthru_map_sg() by returning
early if the request is greater than the maximum bio size. This allows
us to drop the sg_cnt variable.
This should not result in any functional change but makes the code
clearer and more understandable. The original code allocated a truncated
bio then would return EINVAL when bio_add_pc_page() filled that bio. The
new code just returns EINVAL early if this would happen.
Fixes: c1fef73f793b ("nvmet: add passthru code to process commands")
Signed-off-by: Logan Gunthorpe <logang@deltatee.com>
Suggested-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
| -rw-r--r-- | drivers/nvme/target/passthru.c | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c index 323046e1d67f..0814cba8298a 100644 --- a/drivers/nvme/target/passthru.c +++ b/drivers/nvme/target/passthru.c @@ -187,18 +187,20 @@ static void nvmet_passthru_req_done(struct request *rq, static int nvmet_passthru_map_sg(struct nvmet_req *req, struct request *rq) { - int sg_cnt = req->sg_cnt; struct scatterlist *sg; int op_flags = 0; struct bio *bio; int i, ret; + if (req->sg_cnt > BIO_MAX_PAGES) + return -EINVAL; + if (req->cmd->common.opcode == nvme_cmd_flush) op_flags = REQ_FUA; else if (nvme_is_write(req->cmd)) op_flags = REQ_SYNC | REQ_IDLE; - bio = bio_alloc(GFP_KERNEL, min(sg_cnt, BIO_MAX_PAGES)); + bio = bio_alloc(GFP_KERNEL, req->sg_cnt); bio->bi_end_io = bio_put; bio->bi_opf = req_op(rq) | op_flags; @@ -208,7 +210,6 @@ static int nvmet_passthru_map_sg(struct nvmet_req *req, struct request *rq) bio_put(bio); return -EINVAL; } - sg_cnt--; } ret = blk_rq_append_bio(rq, &bio); |