From: Aya Levin <ayal@nvidia.com>
Date: Thu, 23 Dec 2021 14:38:28 +0200
Subject: net/mlx5e: Fix page DMA map/unmap attributes
Patch-mainline: v5.17-rc1
Git-commit: 0b7cfa4082fbf550595bc0e40f05614bd83bf0cd
References: bsc#1196468

Driver initiates DMA sync, hence it may skip CPU sync. Add
DMA_ATTR_SKIP_CPU_SYNC as input attribute both to dma_map_page and
dma_unmap_page to avoid redundant sync with the CPU.
When forcing the device to work with SWIOTLB, the extra sync might cause
data corruption. The driver unmaps the whole page while the hardware
used just a part of the bounce buffer. So syncing overrides the entire
page with bounce buffer that only partially contains real data.

Fixes: bc77b240b3c5 ("net/mlx5e: Add fragmented memory support for RX multi packet WQE")
Fixes: db05815b36cb ("net/mlx5e: Add XSK zero-copy support")
Signed-off-by: Aya Levin <ayal@nvidia.com>
Reviewed-by: Gal Pressman <gal@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/mellanox/mlx5/core/en_rx.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

--- a/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
@@ -228,8 +228,8 @@ static inline int mlx5e_page_alloc_mappe
 	if (unlikely(!dma_info->page))
 		return -ENOMEM;
 
-	dma_info->addr = dma_map_page(rq->pdev, dma_info->page, 0,
-				      PAGE_SIZE, rq->buff.map_dir);
+	dma_info->addr = dma_map_page_attrs(rq->pdev, dma_info->page, 0, PAGE_SIZE,
+					    rq->buff.map_dir, DMA_ATTR_SKIP_CPU_SYNC);
 	if (unlikely(dma_mapping_error(rq->pdev, dma_info->addr))) {
 		put_page(dma_info->page);
 		dma_info->page = NULL;
@@ -241,7 +241,8 @@ static inline int mlx5e_page_alloc_mappe
 
 void mlx5e_page_dma_unmap(struct mlx5e_rq *rq, struct mlx5e_dma_info *dma_info)
 {
-	dma_unmap_page(rq->pdev, dma_info->addr, PAGE_SIZE, rq->buff.map_dir);
+	dma_unmap_page_attrs(rq->pdev, dma_info->addr, PAGE_SIZE, rq->buff.map_dir,
+			     DMA_ATTR_SKIP_CPU_SYNC);
 }
 
 void mlx5e_page_release(struct mlx5e_rq *rq, struct mlx5e_dma_info *dma_info,