On 3/21/19 4:12 PM, Christoph Hellwig wrote:
> We always have exactly one segment, so we can simply call dma_map_bvec.
>
> Signed-off-by: Christoph Hellwig <hch@xxxxxx>
> ---
> drivers/nvme/host/pci.c | 23 ++++++++++-------------
> 1 file changed, 10 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index bc4ee869fe82..a7dad24e0406 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -221,7 +221,7 @@ struct nvme_iod {
> int npages; /* In the PRP list. 0 means small pool in use */
> int nents; /* Used in scatterlist */
> dma_addr_t first_dma;
> - struct scatterlist meta_sg; /* metadata requires single contiguous buffer */
> + dma_addr_t meta_dma;
> struct scatterlist *sg;
> struct scatterlist inline_sg[0];
> };
> @@ -592,13 +592,16 @@ static void nvme_unmap_data(struct nvme_dev *dev, struct request *req)
> dma_addr_t dma_addr = iod->first_dma, next_dma_addr;
> int i;
>
> + if (blk_integrity_rq(req)) {
> + dma_unmap_page(dev->dev, iod->meta_dma,
> + rq_integrity_vec(req)->bv_len, dma_dir);
> + }
> +
> if (iod->nents) {
> /* P2PDMA requests do not need to be unmapped */
> if (!is_pci_p2pdma_page(sg_page(iod->sg)))
> dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
>
> - if (blk_integrity_rq(req))
> - dma_unmap_sg(dev->dev, &iod->meta_sg, 1, dma_dir);
> }
>
> if (iod->npages == 0)
> @@ -861,17 +864,11 @@ static blk_status_t nvme_map_data(struct nvme_dev *dev, struct request *req,
>
> ret = BLK_STS_IOERR;
> if (blk_integrity_rq(req)) {
> - if (blk_rq_count_integrity_sg(q, req->bio) != 1)
> - goto out;
> -
> - sg_init_table(&iod->meta_sg, 1);
> - if (blk_rq_map_integrity_sg(q, req->bio, &iod->meta_sg) != 1)
> - goto out;
> -
> - if (!dma_map_sg(dev->dev, &iod->meta_sg, 1, dma_dir))
> + iod->meta_dma = dma_map_bvec(dev->dev, rq_integrity_vec(req),
> + dma_dir, 0);
> + if (dma_mapping_error(dev->dev, iod->meta_dma))
> goto out;
> -
> - cmnd->rw.metadata = cpu_to_le64(sg_dma_address(&iod->meta_sg));
> + cmnd->rw.metadata = cpu_to_le64(iod->meta_dma);
> }
>
> return BLK_STS_OK;
>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@xxxxxxx>
