Re: [PATCH net-next v1 3/3] net/mlx5e: TC, Add support for VxLAN GBP encap/decap flows offload

[Gavin Li <gavinl@nvidia.com>]

On 2/15/2023 11:36 AM, Gavin Li wrote:
> External email: Use caution opening links or attachments
>
>
> On 2/14/2023 11:26 PM, Alexander Lobakin wrote:
>> External email: Use caution opening links or attachments
>>
>>
>> From: Gavin Li <gavinl@nvidia.com>
>> Date: Tue, 14 Feb 2023 15:41:37 +0200
>>
>>> Add HW offloading support for TC flows with VxLAN GBP encap/decap.
>>>
>>> Example of encap rule:
>>> tc filter add dev eth0 protocol ip ingress flower \
>>>      action tunnel_key set id 42 vxlan_opts 512 \
>>>      action mirred egress redirect dev vxlan1
>>>
>>> Example of decap rule:
>>> tc filter add dev vxlan1 protocol ip ingress flower \
>>>      enc_key_id 42 enc_dst_port 4789 vxlan_opts 1024 \
>>>      action tunnel_key unset action mirred egress redirect dev eth0
>>>
>>> Change-Id: I48f61d02201bf3f79dcbe5d0f022f7bb27ed630f
>>> Signed-off-by: Gavin Li <gavinl@nvidia.com>
>>> Reviewed-by: Roi Dayan <roid@nvidia.com>
>>> Reviewed-by: Maor Dickman <maord@nvidia.com>
>>> Acked-by: Saeed Mahameed <saeedm@nvidia.com>
>>> ---
>>>   .../mellanox/mlx5/core/en/tc_tun_vxlan.c      | 85 
>>> ++++++++++++++++++-
>>>   include/linux/mlx5/device.h                   |  6 ++
>>>   include/linux/mlx5/mlx5_ifc.h                 | 13 ++-
>>>   3 files changed, 100 insertions(+), 4 deletions(-)
>>>
>>> diff --git 
>>> a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_vxlan.c 
>>> b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_vxlan.c
>>> index 1f62c702b625..444512ca9e0d 100644
>>> --- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_vxlan.c
>>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun_vxlan.c
>>> @@ -1,6 +1,7 @@
>>>   // SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB
>>>   /* Copyright (c) 2018 Mellanox Technologies. */
>>>
>>> +#include <net/ip_tunnels.h>
>>>   #include <net/vxlan.h>
>>>   #include "lib/vxlan.h"
>>>   #include "en/tc_tun.h"
>>> @@ -86,9 +87,11 @@ static int mlx5e_gen_ip_tunnel_header_vxlan(char 
>>> buf[],
>>>        const struct ip_tunnel_key *tun_key = &e->tun_info->key;
>>>        __be32 tun_id = tunnel_id_to_key32(tun_key->tun_id);
>>>        struct udphdr *udp = (struct udphdr *)(buf);
>>> +     const struct vxlan_metadata *md;
>>>        struct vxlanhdr *vxh;
>>>
>>> -     if (tun_key->tun_flags & TUNNEL_VXLAN_OPT)
>>> +     if (tun_key->tun_flags & TUNNEL_VXLAN_OPT &&
>> A separate pair of braces is preferred around bitops.
ACK
>>
>>> +         e->tun_info->options_len != sizeof(*md))
>>>                return -EOPNOTSUPP;
>>>        vxh = (struct vxlanhdr *)((char *)udp + sizeof(struct udphdr));
>>>        *ip_proto = IPPROTO_UDP;
>>> @@ -96,6 +99,70 @@ static int mlx5e_gen_ip_tunnel_header_vxlan(char 
>>> buf[],
>>>        udp->dest = tun_key->tp_dst;
>>>        vxh->vx_flags = VXLAN_HF_VNI;
>>>        vxh->vx_vni = vxlan_vni_field(tun_id);
>>> +     if (tun_key->tun_flags & TUNNEL_VXLAN_OPT) {
>>> +             md = ip_tunnel_info_opts((struct ip_tunnel_info 
>>> *)e->tun_info);
>>> +             vxlan_build_gbp_hdr(vxh, tun_key->tun_flags,
>>> +                                 (struct vxlan_metadata *)md);
>> Maybe constify both ip_tunnel_info_opts() and vxlan_build_gbp_hdr()
>> arguments instead of working around by casting away?
> ACK. Sorry for the confusion---I misunderstood the comment.
This ip_tunnel_info_opts is tricky to use const to annotate the arg 
because it will have to cast from const to non-const again upon returning.
>>
>>> +     }
>>> +
>>> +     return 0;
>>> +}
>>> +
>>> +static int mlx5e_tc_tun_parse_vxlan_gbp_option(struct mlx5e_priv 
>>> *priv,
>>> +                                            struct mlx5_flow_spec 
>>> *spec,
>>> +                                            struct flow_cls_offload 
>>> *f)
>>> +{
>>> +     struct flow_rule *rule = flow_cls_offload_flow_rule(f);
>>> +     struct netlink_ext_ack *extack = f->common.extack;
>>> +     struct flow_match_enc_opts enc_opts;
>>> +     void *misc5_c, *misc5_v;
>>> +     u32 *gbp, *gbp_mask;
>>> +
>>> +     flow_rule_match_enc_opts(rule, &enc_opts);
>>> +
>>> +     if (memchr_inv(&enc_opts.mask->data, 0, 
>>> sizeof(enc_opts.mask->data)) &&
>>> +         !MLX5_CAP_ESW_FT_FIELD_SUPPORT_2(priv->mdev, 
>>> tunnel_header_0_1)) {
>>> +             NL_SET_ERR_MSG_MOD(extack,
>>> +                                "Matching on VxLAN GBP is not 
>>> supported");
>>> +             netdev_warn(priv->netdev,
>>> +                         "Matching on VxLAN GBP is not supported\n");
>>> +             return -EOPNOTSUPP;
>>> +     }
>>> +
>>> +     if (enc_opts.key->dst_opt_type != TUNNEL_VXLAN_OPT) {
>>> +             NL_SET_ERR_MSG_MOD(extack,
>>> +                                "Wrong VxLAN option type: not GBP");
>> Fits into one line I believe.
ACK
>>
>>> + netdev_warn(priv->netdev,
>>> +                         "Wrong VxLAN option type: not GBP\n");
>>> +             return -EOPNOTSUPP;
>>> +     }
>>> +
>>> +     if (enc_opts.key->len != sizeof(*gbp) ||
>>> +         enc_opts.mask->len != sizeof(*gbp_mask)) {
>>> +             NL_SET_ERR_MSG_MOD(extack,
>>> +                                "VxLAN GBP option/mask len is not 
>>> 32 bits");
>>> +             netdev_warn(priv->netdev,
>>> +                         "VxLAN GBP option/mask len is not 32 
>>> bits\n");
>>> +             return -EINVAL;
>>> +     }
>>> +
>>> +     gbp = (u32 *)&enc_opts.key->data[0];
>>> +     gbp_mask = (u32 *)&enc_opts.mask->data[0];
>>> +
>>> +     if (*gbp_mask & ~VXLAN_GBP_MASK) {
>>> +             NL_SET_ERR_MSG_MOD(extack,
>>> +                                "Wrong VxLAN GBP mask");
>> You can use new NL_SET_ERR_MSG_FMT_MOD() here to print @gbp_mask to the
>> user, as you do it next line.
ACK
>>
>>> + netdev_warn(priv->netdev,
>>> +                         "Wrong VxLAN GBP mask(0x%08X)\n", *gbp_mask);
>>> +             return -EINVAL;
>>> +     }
>>> +
>>> +     misc5_c = MLX5_ADDR_OF(fte_match_param, spec->match_criteria, 
>>> misc_parameters_5);
>>> +     misc5_v = MLX5_ADDR_OF(fte_match_param, spec->match_value, 
>>> misc_parameters_5);
>>> +     MLX5_SET(fte_match_set_misc5, misc5_c, tunnel_header_0, 
>>> *gbp_mask);
>>> +     MLX5_SET(fte_match_set_misc5, misc5_v, tunnel_header_0, *gbp);
>>> +
>>> +     spec->match_criteria_enable |= MLX5_MATCH_MISC_PARAMETERS_5;
>>>
>>>        return 0;
>>>   }
>> Thanks,
>> Olek