[PATCH 11/12] lpfc: Use sg_dma_address and sg_dma_len macros for NVMe I/O

From: James Smart <jsmart2021@gmail.com>
To: linux-scsi@vger.kernel.org
Cc: James Smart <jsmart2021@gmail.com>,
	Nigel Kirkland <nkirkland2304@gmail.com>
Subject: [PATCH 11/12] lpfc: Use sg_dma_address and sg_dma_len macros for NVMe I/O
Date: Thu,  5 May 2022 20:55:18 -0700	[thread overview]
Message-ID: <20220506035519.50908-12-jsmart2021@gmail.com> (raw)
In-Reply-To: <20220506035519.50908-1-jsmart2021@gmail.com>

NVME I/O problems may be seen on IOMMU enabled platforms. Adapter I/O's
failing with transfer length mismatches.

The sg list processing routine for nvme I/O is accessing the sg entry
directly for the length and address fields. On some iommu platforms,
contigous mappings are compressed to the first sg entry with the sum
of the lengths set to the sg entry dma_length field. The length fields
are left for later use by the unmap call. As such, the driver didn't see
the actual dma_length value, just the first entries length value.
Drivers are to use the sg_dma_length and sg_dma_address macros to
reference the sg entry. The macros select the proper length field
(dma_length or length) to reference.

Fix the offending code to use the sg_dma_xxx macros.

Signed-off-by: Nigel Kirkland <nkirkland2304@gmail.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
---
 drivers/scsi/lpfc/lpfc_nvme.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_nvme.c b/drivers/scsi/lpfc/lpfc_nvme.c
index 3aebd01e07fd..5385f4de5523 100644
--- a/drivers/scsi/lpfc/lpfc_nvme.c
+++ b/drivers/scsi/lpfc/lpfc_nvme.c
@@ -1401,8 +1401,8 @@ lpfc_nvme_prep_io_dma(struct lpfc_vport *vport,
 				if ((nseg - 1) == i)
 					bf_set(lpfc_sli4_sge_last, sgl, 1);
 
-				physaddr = data_sg->dma_address;
-				dma_len = data_sg->length;
+				physaddr = sg_dma_address(data_sg);
+				dma_len = sg_dma_len(data_sg);
 				sgl->addr_lo = cpu_to_le32(
 							 putPaddrLow(physaddr));
 				sgl->addr_hi = cpu_to_le32(
-- 
2.26.2

