[PATCH 7/8] nvme-pci: replace NVME_MAX_KB_SZ with NVME_MAX_BYTE

Christoph Hellwig hch at lst.de
Mon Jun 23 07:12:29 PDT 2025


Having a define in kiB units is a bit weird.  Also update the
comment now that there is not scatterlist limit.

Signed-off-by: Christoph Hellwig <hch at lst.de>
Reviewed-by: Daniel Gomez <da.gomez at samsung.com>
Reviewed-by: Leon Romanovsky <leonro at nvidia.com>
---
 drivers/nvme/host/pci.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index 040ed906c580..4bcd1fdf9a71 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -38,10 +38,9 @@
 #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.
+ * Arbitrary upper bound.
  */
-#define NVME_MAX_KB_SZ	8192
+#define NVME_MAX_BYTES		SZ_8M
 #define NVME_MAX_NR_DESCRIPTORS	5
 
 /*
@@ -413,7 +412,7 @@ static bool nvme_dbbuf_update_and_check_event(u16 value, __le32 *dbbuf_db,
  */
 static __always_inline int nvme_pci_npages_prp(void)
 {
-	unsigned max_bytes = (NVME_MAX_KB_SZ * 1024) + NVME_CTRL_PAGE_SIZE;
+	unsigned max_bytes = NVME_MAX_BYTES + NVME_CTRL_PAGE_SIZE;
 	unsigned nprps = DIV_ROUND_UP(max_bytes, NVME_CTRL_PAGE_SIZE);
 	return DIV_ROUND_UP(8 * nprps, NVME_CTRL_PAGE_SIZE - 8);
 }
@@ -3367,7 +3366,8 @@ static struct nvme_dev *nvme_pci_alloc_dev(struct pci_dev *pdev,
 	 * over a single page.
 	 */
 	dev->ctrl.max_hw_sectors = min_t(u32,
-		NVME_MAX_KB_SZ << 1, dma_opt_mapping_size(&pdev->dev) >> 9);
+			NVME_MAX_BYTES >> SECTOR_SHIFT,
+			dma_opt_mapping_size(&pdev->dev) >> 9);
 	dev->ctrl.max_segments = NVME_MAX_SEGS;
 	dev->ctrl.max_integrity_segments = 1;
 	return dev;
-- 
2.47.2




More information about the Linux-nvme mailing list