[PATCH 5/7] libmlx4: add IBoE support

Or Gerlitz
2011-07-19T09:32:52Z

Modify libmlx4 to support IBoE, where 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-VPRAkNaXOzVS1MOuV/RT9w@public.gmane.org>

Signed-off-by: Or Gerlitz <ogerlitz-VPRAkNaXOzVWk0Htik3J/w@public.gmane.org>
---
src/mlx4.h | 1 +
src/qp.c | 1 +
src/verbs.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++--
src/wqe.h | 3 ++-
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..6620ac2 100644
--- a/src/verbs.c
+++ b/src/verbs.c
@@ -614,9 +614,45 @@ 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 +661,11 @@ 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 {
--
1.5.5