nvme-pci: use blk_map_iter for p2p metadata

The dma_map_bvec helper doesn't work for p2p data, so use the same
blk_map_iter method that sgl uses for this memory type.

Reported-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index c916176bd9f058b49e6e6768675711df52b15765..72fb675a696f49a9819744da84f8f85ed9aed33d 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -1042,7 +1042,7 @@ static blk_status_t nvme_map_data(struct request *req)
        return nvme_pci_setup_data_prp(req, &iter);
 }
 
-static blk_status_t nvme_pci_setup_meta_sgls(struct request *req)
+static blk_status_t nvme_pci_setup_meta_iter(struct request *req)
 {
        struct nvme_queue *nvmeq = req->mq_hctx->driver_data;
        unsigned int entries = req->nr_integrity_segments;
@@ -1072,8 +1072,12 @@ static blk_status_t nvme_pci_setup_meta_sgls(struct request *req)
         * descriptor provides an explicit length, so we're relying on that
         * mechanism to catch any misunderstandings between the application and
         * device.
+        *
+        * P2P DMA also needs to use the blk_dma_iter method, so mptr setup
+        * leverages this routine when that happens.
         */
-       if (entries == 1 && !(nvme_req(req)->flags & NVME_REQ_USERCMD)) {
+       if (!nvme_ctrl_meta_sgl_supported(&dev->ctrl) ||
+           (entries == 1 && !(nvme_req(req)->flags & NVME_REQ_USERCMD))) {
                iod->cmd.common.metadata = cpu_to_le64(iter.addr);
                iod->meta_total_len = iter.len;
                iod->meta_dma = iter.addr;
@@ -1114,6 +1118,9 @@ static blk_status_t nvme_pci_setup_meta_mptr(struct request *req)
        struct nvme_queue *nvmeq = req->mq_hctx->driver_data;
        struct bio_vec bv = rq_integrity_vec(req);
 
+       if (is_pci_p2pdma_page(bv.bv_page))
+               return nvme_pci_setup_meta_iter(req);
+
        iod->meta_dma = dma_map_bvec(nvmeq->dev->dev, &bv, rq_dma_dir(req), 0);
        if (dma_mapping_error(nvmeq->dev->dev, iod->meta_dma))
                return BLK_STS_IOERR;
@@ -1128,7 +1135,7 @@ static blk_status_t nvme_map_metadata(struct request *req)
 
        if ((iod->cmd.common.flags & NVME_CMD_SGL_METABUF) &&
            nvme_pci_metadata_use_sgls(req))
-               return nvme_pci_setup_meta_sgls(req);
+               return nvme_pci_setup_meta_iter(req);
        return nvme_pci_setup_meta_mptr(req);
 }