nvme: simplify nvme_setup_prps calling convention

Pass back a true/false value instead of the length which needs a compare
with the bytes in the request and drop the pointless gfp_t argument.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 8a564f4ecf9913643a0ff89195237afba82a43e7..75970fdeeecb3026ca31d9e51b86dba8a79735f9 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -709,9 +709,8 @@ release_iod:
                blk_mq_complete_request(req, error);
 }
 
-/* length is in bytes.  gfp flags indicates whether we may sleep. */
-static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
-               int total_len, gfp_t gfp)
+static bool nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
+               int total_len)
 {
        struct dma_pool *pool;
        int length = total_len;
@@ -727,7 +726,7 @@ static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
 
        length -= (page_size - offset);
        if (length <= 0)
-               return total_len;
+               return true;
 
        dma_len -= (page_size - offset);
        if (dma_len) {
@@ -740,7 +739,7 @@ static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
 
        if (length <= page_size) {
                iod->first_dma = dma_addr;
-               return total_len;
+               return true;
        }
 
        nprps = DIV_ROUND_UP(length, page_size);
@@ -752,11 +751,11 @@ static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
                iod->npages = 1;
        }
 
-       prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
+       prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
        if (!prp_list) {
                iod->first_dma = dma_addr;
                iod->npages = -1;
-               return (total_len - length) + page_size;
+               return false;
        }
        list[0] = prp_list;
        iod->first_dma = prp_dma;
@@ -764,9 +763,9 @@ static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
        for (;;) {
                if (i == page_size >> 3) {
                        __le64 *old_prp_list = prp_list;
-                       prp_list = dma_pool_alloc(pool, gfp, &prp_dma);
+                       prp_list = dma_pool_alloc(pool, GFP_ATOMIC, &prp_dma);
                        if (!prp_list)
-                               return total_len - length;
+                               return false;
                        list[iod->npages++] = prp_list;
                        prp_list[0] = old_prp_list[i - 1];
                        old_prp_list[i - 1] = cpu_to_le64(prp_dma);
@@ -786,7 +785,7 @@ static int nvme_setup_prps(struct nvme_dev *dev, struct nvme_iod *iod,
                dma_len = sg_dma_len(sg);
        }
 
-       return total_len;
+       return true;
 }
 
 static void nvme_submit_priv(struct nvme_queue *nvmeq, struct request *req,
@@ -952,8 +951,7 @@ static int nvme_queue_rq(struct blk_mq_hw_ctx *hctx,
                if (!dma_map_sg(nvmeq->q_dmadev, iod->sg, iod->nents, dma_dir))
                        goto retry_cmd;
 
-               if (blk_rq_bytes(req) !=
-                    nvme_setup_prps(dev, iod, blk_rq_bytes(req), GFP_ATOMIC)) {
+               if (!nvme_setup_prps(dev, iod, blk_rq_bytes(req))) {
                        dma_unmap_sg(dev->dev, iod->sg, iod->nents, dma_dir);
                        goto retry_cmd;
                }