From 64848f062e33df61fb1f9f7b7a3dc7b44e0d36d7 Mon Sep 17 00:00:00 2001 From: Pieter Jansen van Vuuren Date: Thu, 24 Aug 2023 12:28:41 +0100 Subject: [PATCH] sfc: introduce pedit add actions on the ipv4 ttl field Introduce pedit add actions and use it to achieve decrement ttl offload. Decrement ttl can be achieved by adding 0xff to the ttl field. Co-developed-by: Edward Cree Signed-off-by: Edward Cree Signed-off-by: Pieter Jansen van Vuuren Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/tc.c | 46 +++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/drivers/net/ethernet/sfc/tc.c b/drivers/net/ethernet/sfc/tc.c index 354c635be59ff..dfe3a8bf74f04 100644 --- a/drivers/net/ethernet/sfc/tc.c +++ b/drivers/net/ethernet/sfc/tc.c @@ -1054,6 +1054,47 @@ static int efx_tc_complete_mac_mangle(struct efx_nic *efx, return 0; } +static int efx_tc_pedit_add(struct efx_nic *efx, struct efx_tc_action_set *act, + const struct flow_action_entry *fa, + struct netlink_ext_ack *extack) +{ + switch (fa->mangle.htype) { + case FLOW_ACT_MANGLE_HDR_TYPE_IP4: + switch (fa->mangle.offset) { + case offsetof(struct iphdr, ttl): + /* check that pedit applies to ttl only */ + if (fa->mangle.mask != ~EFX_TC_HDR_TYPE_TTL_MASK) + break; + + /* Adding 0xff is equivalent to decrementing the ttl. + * Other added values are not supported. + */ + if ((fa->mangle.val & EFX_TC_HDR_TYPE_TTL_MASK) != U8_MAX) + break; + + /* check that we do not decrement ttl twice */ + if (!efx_tc_flower_action_order_ok(act, + EFX_TC_AO_DEC_TTL)) { + NL_SET_ERR_MSG_MOD(extack, "Unsupported: multiple dec ttl"); + return -EOPNOTSUPP; + } + act->do_ttl_dec = 1; + return 0; + default: + break; + } + break; + default: + break; + } + + NL_SET_ERR_MSG_FMT_MOD(extack, + "Unsupported: ttl add action type %x %x %x/%x", + fa->mangle.htype, fa->mangle.offset, + fa->mangle.val, fa->mangle.mask); + return -EOPNOTSUPP; +} + /** * efx_tc_mangle() - handle a single 32-bit (or less) pedit * @efx: NIC we're installing a flow rule on @@ -2014,6 +2055,11 @@ static int efx_tc_flower_replace(struct efx_nic *efx, act->vlan_proto[act->vlan_push] = fa->vlan.proto; act->vlan_push++; break; + case FLOW_ACTION_ADD: + rc = efx_tc_pedit_add(efx, act, fa, extack); + if (rc < 0) + goto release; + break; case FLOW_ACTION_MANGLE: rc = efx_tc_mangle(efx, act, fa, &mung, extack, &match); if (rc < 0) -- 2.30.2