Add IBoE support

Modify libmlx4 to support IBoE.  The only user space piece to handle
is the creation of UD address handles - the L2 Ethernet attributes
have to be resolved from the DGID.  Derived from work by Eli Cohen
<eli@mellanox.co.il>

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>

4 files changed, 51 insertions, 3 deletions

diff --git a/src/mlx4.h b/src/mlx4.h
index 4445998..b277b06 100644
--- a/src/mlx4.h
+++ b/src/mlx4.h
@@ -241,6 +241,7 @@ struct mlx4_av {
 struct mlx4_ah {
 	struct ibv_ah			ibv_ah;
 	struct mlx4_av			av;
+	uint8_t				mac[6];
 };
 
 static inline unsigned long align(unsigned long val, unsigned long align)
diff --git a/src/qp.c b/src/qp.c
index ec138cd..4d79e38 100644
--- a/src/qp.c
+++ b/src/qp.c
@@ -144,6 +144,7 @@ static void set_datagram_seg(struct mlx4_wqe_datagram_seg *dseg,
 	memcpy(dseg->av, &to_mah(wr->wr.ud.ah)->av, sizeof (struct mlx4_av));
 	dseg->dqpn = htonl(wr->wr.ud.remote_qpn);
 	dseg->qkey = htonl(wr->wr.ud.remote_qkey);
+	memcpy(dseg->mac, to_mah(wr->wr.ud.ah)->mac, 6);
 }
 
 static void __set_data_seg(struct mlx4_wqe_data_seg *dseg, struct ibv_sge *sg)
diff --git a/src/verbs.c b/src/verbs.c
index 1ac1362..389801c 100644
--- a/src/verbs.c
+++ b/src/verbs.c
@@ -614,9 +614,44 @@ int mlx4_destroy_qp(struct ibv_qp *ibqp)
 	return 0;
 }
 
+static int link_local_gid(const union ibv_gid *gid)
+{
+	uint32_t hi = *(uint32_t *)(gid->raw);
+	uint32_t lo = *(uint32_t *)(gid->raw + 4);
+	if (hi == htonl(0xfe800000) && lo == 0)
+		return 1;
+
+	return 0;
+}
+
+static uint16_t get_vlan_id(union ibv_gid *gid)
+{
+	uint16_t vid;
+	vid = gid->raw[11] << 8 | gid->raw[12];
+	return vid < 0x1000 ? vid : 0xffff;
+}
+
+static int mlx4_resolve_grh_to_l2(struct mlx4_ah *ah, struct ibv_ah_attr *attr)
+{
+	if (get_vlan_id(&attr->grh.dgid) != 0xffff)
+		return 1;
+
+	if (link_local_gid(&attr->grh.dgid)) {
+		memcpy(ah->mac, &attr->grh.dgid.raw[8], 3);
+		memcpy(ah->mac + 3, &attr->grh.dgid.raw[13], 3);
+		ah->mac[0] ^= 2;
+		return 0;
+	} else
+		return 1;
+}
+
 struct ibv_ah *mlx4_create_ah(struct ibv_pd *pd, struct ibv_ah_attr *attr)
 {
 	struct mlx4_ah *ah;
+	struct ibv_port_attr port_attr;
+
+	if (ibv_query_port(pd->context, attr->port_num, &port_attr))
+		return NULL;
 
 	ah = malloc(sizeof *ah);
 	if (!ah)
@@ -625,8 +660,12 @@ struct ibv_ah *mlx4_create_ah(struct ibv_pd *pd, struct ibv_ah_attr *attr)
 	memset(&ah->av, 0, sizeof ah->av);
 
 	ah->av.port_pd   = htonl(to_mpd(pd)->pdn | (attr->port_num << 24));
-	ah->av.g_slid    = attr->src_path_bits;
-	ah->av.dlid      = htons(attr->dlid);
+
+	if (port_attr.link_layer != IBV_LINK_LAYER_ETHERNET) {
+		ah->av.g_slid = attr->src_path_bits;
+		ah->av.dlid   = htons(attr->dlid);
+	}
+
 	if (attr->static_rate) {
 		ah->av.stat_rate = attr->static_rate + MLX4_STAT_RATE_OFFSET;
 		/* XXX check rate cap? */
@@ -642,6 +681,12 @@ struct ibv_ah *mlx4_create_ah(struct ibv_pd *pd, struct ibv_ah_attr *attr)
 		memcpy(ah->av.dgid, attr->grh.dgid.raw, 16);
 	}
 
+	if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET)
+		if (mlx4_resolve_grh_to_l2(ah, attr)) {
+			free(ah);
+			return NULL;
+		}
+
 	return &ah->ibv_ah;
 }
 
diff --git a/src/wqe.h b/src/wqe.h
index 6f7f309..043f0da 100644
--- a/src/wqe.h
+++ b/src/wqe.h
@@ -78,7 +78,8 @@ struct mlx4_wqe_datagram_seg {
 	uint32_t		av[8];
 	uint32_t		dqpn;
 	uint32_t		qkey;
-	uint32_t		reserved[2];
+	uint16_t		reserved;
+	uint8_t			mac[6];
 };
 
 struct mlx4_wqe_data_seg {