Re: [PATCH net-next V2 09/12] net/mlx5_core: Make ipv4/ipv6 location more clear

On Mon, Jan 11, 2016 at 2:17 PM, David Laight [off-list ref] wrote:

From: Or Gerlitz

quoted

Sent: 10 January 2016 08:40
Change the mlx5 firmware interface header to make it
more clear which bytes should be used by IPv4 or
IPv6 addresses.

Signed-off-by: Maor Gottlieb <redacted>
Signed-off-by: Moni Shoua <redacted>
Signed-off-by: Matan Barak <redacted>
---
 include/linux/mlx5/mlx5_ifc.h | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h
index 7f16695..68d73f8 100644
--- a/include/linux/mlx5/mlx5_ifc.h
+++ b/include/linux/mlx5/mlx5_ifc.h

@@ -298,6 +298,22 @@ struct mlx5_ifc_odp_per_transport_service_cap_bits {
      u8         reserved_1[0x1a];
 };

+struct mlx5_ifc_ipv4_layout_bits {
+     u8         reserved_0[0x60];
+
+     u8         ipv4[0x20];
+};
+
+struct mlx5_ifc_ipv6_layout_bits {
+     u8         ipv6[16][0x8];
+};
+
+union mlx5_ifc_ipv6_layout_ipv4_layout_auto_bits {
+     struct mlx5_ifc_ipv6_layout_bits ipv6_layout;
+     struct mlx5_ifc_ipv4_layout_bits ipv4_layout;
+     u8         reserved_0[0x80];
+};

I like the way these names just roll off the tongue :-)

quoted

+
 struct mlx5_ifc_fte_match_set_lyr_2_4_bits {
      u8         smac_47_16[0x20];

@@ -328,9 +344,9 @@ struct mlx5_ifc_fte_match_set_lyr_2_4_bits {
      u8         udp_sport[0x10];
      u8         udp_dport[0x10];

-     u8         src_ip[4][0x20];
+     union mlx5_ifc_ipv6_layout_ipv4_layout_auto_bits src_ipv4_src_ipv6;

-     u8         dst_ip[4][0x20];
+     union mlx5_ifc_ipv6_layout_ipv4_layout_auto_bits dst_ipv4_dst_ipv6;
 };

Have you considered just how long the line of code to access these
fields will be?
It might be better to do (I think it compiles):
        union {
                u8      src_ipv6[16][0x8];
                struct {
                        u8      src_ipv4_pad[0x60];
                        u8      src_ipv4[0x20];
                }
        };
Repeated for the 'dst' addresses.
Then fixup the definition of src_ipv4[] (and probably src_ipv6[]) to
be much clearer about how the addresses are supplied.

David,

As Matan commented, these is an auto generated header, done by a tool
that runs over the firmware spec.

Indeed, the names here are sort of odd / too long and Matan/Maor will
provide the feedback into the internal chain (tool/spec, depends where
the problem is) - however, we would prefer to address that as
incremental fix over the code after the series is applied, hope this
makes sense to you.

Or.