nvme-pci: add a symolic name for the small pool size

Open coding magic numbers in multiple places is never a good idea.

Signed-off-by: Leon Romanovsky <leon@kernel.org>
[hch: split from a larger patch]
Signed-off-by: Christoph Hellwig <hch@lst.de>

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 16e2ce25da8324f984f25e689f9cd53a0ce8c495..5396fe30eb94045774d84d474de33668e5f706b4 100644 (file)
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -37,6 +37,8 @@
 
 #define SGES_PER_PAGE  (NVME_CTRL_PAGE_SIZE / sizeof(struct nvme_sgl_desc))
 
+#define NVME_SMALL_POOL_SIZE   256
+
 /*
  * These can be higher, but we need to ensure that any command doesn't
  * require an sg allocation that needs more than a page of data.
@@ -407,7 +409,7 @@ static struct nvme_descriptor_pools *
 nvme_setup_descriptor_pools(struct nvme_dev *dev, unsigned numa_node)
 {
        struct nvme_descriptor_pools *pools = &dev->descriptor_pools[numa_node];
-       size_t small_align = 256;
+       size_t small_align = NVME_SMALL_POOL_SIZE;
 
        if (pools->small)
                return pools; /* already initialized */
@@ -422,7 +424,7 @@ nvme_setup_descriptor_pools(struct nvme_dev *dev, unsigned numa_node)
 
        /* Optimisation for I/Os between 4k and 128k */
        pools->small = dma_pool_create_node("nvme descriptor 256", dev->dev,
-                       256, small_align, 0, numa_node);
+                       NVME_SMALL_POOL_SIZE, small_align, 0, numa_node);
        if (!pools->small) {
                dma_pool_destroy(pools->large);
                pools->large = NULL;
@@ -689,7 +691,7 @@ static blk_status_t nvme_pci_setup_prps(struct nvme_queue *nvmeq,
        }
 
        if (DIV_ROUND_UP(length, NVME_CTRL_PAGE_SIZE) <=
-           256 / sizeof(__le64))
+           NVME_SMALL_POOL_SIZE / sizeof(__le64))
                iod->flags |= IOD_SMALL_DESCRIPTOR;
 
        prp_list = dma_pool_alloc(nvme_dma_pool(nvmeq, iod), GFP_ATOMIC,
@@ -774,7 +776,7 @@ static blk_status_t nvme_pci_setup_sgls(struct nvme_queue *nvmeq,
                return BLK_STS_OK;
        }
 
-       if (entries <= 256 / sizeof(*sg_list))
+       if (entries <= NVME_SMALL_POOL_SIZE / sizeof(*sg_list))
                iod->flags |= IOD_SMALL_DESCRIPTOR;
 
        sg_list = dma_pool_alloc(nvme_dma_pool(nvmeq, iod), GFP_ATOMIC,