nvme: add helper nvme_map_len()

The helper returns the number of bytes that need to be mapped
using PRPs/SGL entries.

Signed-off-by: Ming Lin <ming.l@ssi.samsung.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
(cherry picked from commit 58b45602751ddf16e57170656670aa5a8f78eeca)

Orabug: 25130845

Signed-off-by: Ashok Vairavan <ashok.vairavan@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index 7f5a4dae1bcfdbca5d258753e6b5c398daf50c82..e0d878d339363098c8ea59f0b26c9d6c580ee790 100644 (file)
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -160,6 +160,14 @@ static inline u64 nvme_block_nr(struct nvme_ns *ns, sector_t sector)
        return (sector >> (ns->lba_shift - 9));
 }
 
+static inline unsigned nvme_map_len(struct request *rq)
+{
+       if (rq->cmd_flags & REQ_DISCARD)
+               return sizeof(struct nvme_dsm_range);
+       else
+               return blk_rq_bytes(rq);
+}
+
 static inline void nvme_setup_flush(struct nvme_ns *ns,
                struct nvme_command *cmnd)
 {

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index ea82c7d83e3428c58f64fad6ed98f1946e16f3fc..ec706faa0262ec93d2c4629abe690ce6fafccc0e 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -361,16 +361,11 @@ static __le64 **iod_list(struct request *req)
        return (__le64 **)(iod->sg + req->nr_phys_segments);
 }
 
-static int nvme_init_iod(struct request *rq, struct nvme_dev *dev)
+static int nvme_init_iod(struct request *rq, unsigned size,
+               struct nvme_dev *dev)
 {
        struct nvme_iod *iod = blk_mq_rq_to_pdu(rq);
        int nseg = rq->nr_phys_segments;
-       unsigned size;
-
-       if (rq->cmd_flags & REQ_DISCARD)
-               size = sizeof(struct nvme_dsm_range);
-       else
-               size = blk_rq_bytes(rq);
 
        if (nseg > NVME_INT_PAGES || size > NVME_INT_BYTES(dev)) {
                iod->sg = kmalloc(nvme_iod_alloc_size(dev, size, nseg), GFP_ATOMIC);
@@ -701,6 +696,7 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
        struct nvme_dev *dev = nvmeq->dev;
        struct request *req = bd->rq;
        struct nvme_command cmnd;
+       unsigned map_len;
        int ret = BLK_MQ_RQ_QUEUE_OK;
 
        /*
@@ -717,7 +713,8 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
                }
        }
 
-       ret = nvme_init_iod(req, dev);
+       map_len = nvme_map_len(req);
+       ret = nvme_init_iod(req, map_len, dev);
        if (ret)
                return ret;