[PATCH] net/mlx5/hws: add the DF bit for IPv4 header in NAT64 action

[Bing Zhao]

From: Erez Shitrit <erezsh at nvidia.com>

We set the DF bit to 1, and re-calculate the csum for that buffer.

Fixes: 06d969a8c5b8 ("net/mlx5/hws: support NAT64 flow action")
Cc: stable at dpdk.org

Signed-off-by: Erez Shitrit <erezsh at nvidia.com>
Acked-by: Bing Zhao <bingz at nvidia.com>
Acked-by: Matan Azrad <matan at nvidia.com>
---
 drivers/net/mlx5/hws/mlx5dr_action.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/mlx5/hws/mlx5dr_action.c b/drivers/net/mlx5/hws/mlx5dr_action.c
index 498c6aa109..3e48739eb5 100644
--- a/drivers/net/mlx5/hws/mlx5dr_action.c
+++ b/drivers/net/mlx5/hws/mlx5dr_action.c
@@ -507,8 +507,11 @@ mlx5dr_action_create_nat64_repalce_state(struct mlx5dr_context *ctx,
 		memcpy(address_prefix, nat64_well_known_pref,
 		       MLX5DR_ACTION_NAT64_HEADER_MINUS_ONE * sizeof(uint32_t));
 	} else {
-		/* In order to fix HW csum issue, make the prefix ready */
-		uint32_t ipv4_pref[] = {0x0, 0xffba0000, 0x0, 0x0, 0x0};
+		/* We make a buffer that contain the right HW csum and the DF bit set.
+		 * 0x00400000 - contain the DF bit in the right place.
+		 * 0xff7a0000 - is the csum for that buffer, calculated via external tool.
+		 */
+		uint32_t ipv4_pref[] = {0x00400000, 0xff7a0000, 0x0, 0x0, 0x0};
 
 		header_size_in_dw = MLX5DR_ACTION_NAT64_IPV4_HEADER;
 		ip_ver = MLX5DR_ACTION_NAT64_IPV4_VER;
-- 
2.34.1