nfp: flower: implement ip fragmentation match offload

Implement ip fragmentation match offloading for both IPv4 and IPv6. Allows
offloading frag, nofrag, first and nofirstfrag classification.

Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -61,6 +61,9 @@
 #define NFP_FLOWER_MASK_MPLS_BOS	BIT(8)
 #define NFP_FLOWER_MASK_MPLS_Q		BIT(0)
 
+#define NFP_FL_IP_FRAG_FIRST		BIT(7)
+#define NFP_FL_IP_FRAGMENTED		BIT(6)
+
 /* Compressed HW representation of TCP Flags */
 #define NFP_FL_TCP_FLAG_URG		BIT(4)
 #define NFP_FL_TCP_FLAG_PSH		BIT(3)

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

@@ -190,6 +190,18 @@ nfp_flower_compile_ip_ext(struct nfp_flower_ip_ext *frame,
 		if (tcp_flags & TCPHDR_URG)
 			frame->flags |= NFP_FL_TCP_FLAG_URG;
 	}
+
+	if (dissector_uses_key(flow->dissector, FLOW_DISSECTOR_KEY_CONTROL)) {
+		struct flow_dissector_key_control *key;
+
+		key = skb_flow_dissector_target(flow->dissector,
+						FLOW_DISSECTOR_KEY_CONTROL,
+						target);
+		if (key->flags & FLOW_DIS_IS_FRAGMENT)
+			frame->flags |= NFP_FL_IP_FRAGMENTED;
+		if (key->flags & FLOW_DIS_FIRST_FRAG)
+			frame->flags |= NFP_FL_IP_FRAG_FIRST;
+	}
 }
 
 static void

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

@@ -48,6 +48,10 @@
 	(TCPHDR_FIN | TCPHDR_SYN | TCPHDR_RST | \
 	 TCPHDR_PSH | TCPHDR_URG)
 
+#define NFP_FLOWER_SUPPORTED_CTLFLAGS \
+	(FLOW_DIS_IS_FRAGMENT | \
+	 FLOW_DIS_FIRST_FRAG)
+
 #define NFP_FLOWER_WHITELIST_DISSECTOR \
 	(BIT(FLOW_DISSECTOR_KEY_CONTROL) | \
 	 BIT(FLOW_DISSECTOR_KEY_BASIC) | \
@@ -322,6 +326,17 @@ nfp_flower_calculate_key_layers(struct nfp_app *app,
 		}
 	}
 
+	if (dissector_uses_key(flow->dissector, FLOW_DISSECTOR_KEY_CONTROL)) {
+		struct flow_dissector_key_control *key_ctl;
+
+		key_ctl = skb_flow_dissector_target(flow->dissector,
+						    FLOW_DISSECTOR_KEY_CONTROL,
+						    flow->key);
+
+		if (key_ctl->flags & ~NFP_FLOWER_SUPPORTED_CTLFLAGS)
+			return -EOPNOTSUPP;
+	}
+
 	ret_key_ls->key_layer = key_layer;
 	ret_key_ls->key_layer_two = key_layer_two;
 	ret_key_ls->key_size = key_size;