nfp: flower: add ipv6 set flow label and hop limit offload

Add ipv6 set flow label and hop limit action offload. Since pedit sets
headers per 4 byte word, we need to ensure that setting either version,
priority, payload_len or nexthdr does not get offloaded.
Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/flower/action.c

@@ -476,12 +476,57 @@ nfp_fl_set_ip6_helper(int opcode_tag, u8 word, __be32 exact, __be32 mask,
 	ip6->head.len_lw = sizeof(*ip6) >> NFP_FL_LW_SIZ;
 }
 
+struct ipv6_hop_limit_word {
+	__be16 payload_len;
+	u8 nexthdr;
+	u8 hop_limit;
+};
+
+static int
+nfp_fl_set_ip6_hop_limit_flow_label(u32 off, __be32 exact, __be32 mask,
+				    struct nfp_fl_set_ipv6_tc_hl_fl *ip_hl_fl)
+{
+	struct ipv6_hop_limit_word *fl_hl_mask;
+	struct ipv6_hop_limit_word *fl_hl;
+
+	switch (off) {
+	case offsetof(struct ipv6hdr, payload_len):
+		fl_hl_mask = (struct ipv6_hop_limit_word *)&mask;
+		fl_hl = (struct ipv6_hop_limit_word *)&exact;
+
+		if (fl_hl_mask->nexthdr || fl_hl_mask->payload_len)
+			return -EOPNOTSUPP;
+
+		ip_hl_fl->ipv6_hop_limit_mask |= fl_hl_mask->hop_limit;
+		ip_hl_fl->ipv6_hop_limit &= ~fl_hl_mask->hop_limit;
+		ip_hl_fl->ipv6_hop_limit |= fl_hl->hop_limit &
+					    fl_hl_mask->hop_limit;
+		break;
+	case round_down(offsetof(struct ipv6hdr, flow_lbl), 4):
+		if (mask & ~IPV6_FLOW_LABEL_MASK ||
+		    exact & ~IPV6_FLOW_LABEL_MASK)
+			return -EOPNOTSUPP;
+
+		ip_hl_fl->ipv6_label_mask |= mask;
+		ip_hl_fl->ipv6_label &= ~mask;
+		ip_hl_fl->ipv6_label |= exact & mask;
+		break;
+	}
+
+	ip_hl_fl->head.jump_id = NFP_FL_ACTION_OPCODE_SET_IPV6_TC_HL_FL;
+	ip_hl_fl->head.len_lw = sizeof(*ip_hl_fl) >> NFP_FL_LW_SIZ;
+
+	return 0;
+}
+
 static int
 nfp_fl_set_ip6(const struct tc_action *action, int idx, u32 off,
 	       struct nfp_fl_set_ipv6_addr *ip_dst,
-	       struct nfp_fl_set_ipv6_addr *ip_src)
+	       struct nfp_fl_set_ipv6_addr *ip_src,
+	       struct nfp_fl_set_ipv6_tc_hl_fl *ip_hl_fl)
 {
 	__be32 exact, mask;
+	int err = 0;
 	u8 word;
 
 	/* We are expecting tcf_pedit to return a big endian value */
@@ -492,7 +537,8 @@ nfp_fl_set_ip6(const struct tc_action *action, int idx, u32 off,
 		return -EOPNOTSUPP;
 
 	if (off < offsetof(struct ipv6hdr, saddr)) {
-		return -EOPNOTSUPP;
+		err = nfp_fl_set_ip6_hop_limit_flow_label(off, exact, mask,
+							  ip_hl_fl);
 	} else if (off < offsetof(struct ipv6hdr, daddr)) {
 		word = (off - offsetof(struct ipv6hdr, saddr)) / sizeof(exact);
 		nfp_fl_set_ip6_helper(NFP_FL_ACTION_OPCODE_SET_IPV6_SRC, word,
@@ -506,7 +552,7 @@ nfp_fl_set_ip6(const struct tc_action *action, int idx, u32 off,
 		return -EOPNOTSUPP;
 	}
 
-	return 0;
+	return err;
 }
 
 static int
@@ -557,6 +603,7 @@ nfp_fl_pedit(const struct tc_action *action, struct tc_cls_flower_offload *flow,
 	     char *nfp_action, int *a_len, u32 *csum_updated)
 {
 	struct nfp_fl_set_ipv6_addr set_ip6_dst, set_ip6_src;
+	struct nfp_fl_set_ipv6_tc_hl_fl set_ip6_tc_hl_fl;
 	struct nfp_fl_set_ip4_ttl_tos set_ip_ttl_tos;
 	struct nfp_fl_set_ip4_addrs set_ip_addr;
 	struct nfp_fl_set_tport set_tport;
@@ -567,6 +614,7 @@ nfp_fl_pedit(const struct tc_action *action, struct tc_cls_flower_offload *flow,
 	u32 offset, cmd;
 	u8 ip_proto = 0;
 
+	memset(&set_ip6_tc_hl_fl, 0, sizeof(set_ip6_tc_hl_fl));
 	memset(&set_ip_ttl_tos, 0, sizeof(set_ip_ttl_tos));
 	memset(&set_ip6_dst, 0, sizeof(set_ip6_dst));
 	memset(&set_ip6_src, 0, sizeof(set_ip6_src));
@@ -593,7 +641,7 @@ nfp_fl_pedit(const struct tc_action *action, struct tc_cls_flower_offload *flow,
 			break;
 		case TCA_PEDIT_KEY_EX_HDR_TYPE_IP6:
 			err = nfp_fl_set_ip6(action, idx, offset, &set_ip6_dst,
-					     &set_ip6_src);
+					     &set_ip6_src, &set_ip6_tc_hl_fl);
 			break;
 		case TCA_PEDIT_KEY_EX_HDR_TYPE_TCP:
 			err = nfp_fl_set_tport(action, idx, offset, &set_tport,
@@ -644,6 +692,15 @@ nfp_fl_pedit(const struct tc_action *action, struct tc_cls_flower_offload *flow,
 		*csum_updated |= TCA_CSUM_UPDATE_FLAG_IPV4HDR |
 				nfp_fl_csum_l4_to_flag(ip_proto);
 	}
+	if (set_ip6_tc_hl_fl.head.len_lw) {
+		nfp_action += act_size;
+		act_size = sizeof(set_ip6_tc_hl_fl);
+		memcpy(nfp_action, &set_ip6_tc_hl_fl, act_size);
+		*a_len += act_size;
+
+		/* Hardware will automatically fix TCP/UDP checksum. */
+		*csum_updated |= nfp_fl_csum_l4_to_flag(ip_proto);
+	}
 	if (set_ip6_dst.head.len_lw && set_ip6_src.head.len_lw) {
 		/* TC compiles set src and dst IPv6 address as a single action,
 		 * the hardware requires this to be 2 separate actions.

drivers/net/ethernet/netronome/nfp/flower/cmsg.h

@@ -68,6 +68,7 @@
 #define NFP_FL_ACTION_OPCODE_SET_IPV4_TTL_TOS	10
 #define NFP_FL_ACTION_OPCODE_SET_IPV6_SRC	11
 #define NFP_FL_ACTION_OPCODE_SET_IPV6_DST	12
+#define NFP_FL_ACTION_OPCODE_SET_IPV6_TC_HL_FL	13
 #define NFP_FL_ACTION_OPCODE_SET_UDP		14
 #define NFP_FL_ACTION_OPCODE_SET_TCP		15
 #define NFP_FL_ACTION_OPCODE_PRE_LAG		16
@@ -83,6 +84,8 @@
 #define NFP_FL_PUSH_VLAN_CFI		BIT(12)
 #define NFP_FL_PUSH_VLAN_VID		GENMASK(11, 0)
 
+#define IPV6_FLOW_LABEL_MASK		cpu_to_be32(0x000fffff)
+
 /* LAG ports */
 #define NFP_FL_LAG_OUT			0xC0DE0000
 
@@ -135,6 +138,17 @@ struct nfp_fl_set_ip4_ttl_tos {
 	__be16 reserved;
 };
 
+struct nfp_fl_set_ipv6_tc_hl_fl {
+	struct nfp_fl_act_head head;
+	u8 ipv6_tc_mask;
+	u8 ipv6_hop_limit_mask;
+	__be16 reserved;
+	u8 ipv6_tc;
+	u8 ipv6_hop_limit;
+	__be32 ipv6_label_mask;
+	__be32 ipv6_label;
+};
+
 struct nfp_fl_set_ipv6_addr {
 	struct nfp_fl_act_head head;
 	__be16 reserved;