IB/mlx4: Update HW GID table while adding vlan GID

When adding a new GID compare the vlan along with the GID and type. This
allows vlan's to have GIDs that alias each other, such as the default
GID. Otherwise they the GID cache view can become inconsistent with the HW
view.

Link: https://lore.kernel.org/r/20191115154457.247763-1-leon@kernel.orgSigned-off-by: Danit Goldberg <danitg@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/mlx4/main.c

@@ -256,6 +256,8 @@ static int mlx4_ib_add_gid(const struct ib_gid_attr *attr, void **context)
 	int hw_update = 0;
 	int i;
 	struct gid_entry *gids = NULL;
+	u16 vlan_id = 0xffff;
+	u8 mac[ETH_ALEN];
 
 	if (!rdma_cap_roce_gid_table(attr->device, attr->port_num))
 		return -EINVAL;
@@ -266,12 +268,16 @@ static int mlx4_ib_add_gid(const struct ib_gid_attr *attr, void **context)
 	if (!context)
 		return -EINVAL;
 
+	ret = rdma_read_gid_l2_fields(attr, &vlan_id, &mac[0]);
+	if (ret)
+		return ret;
 	port_gid_table = &iboe->gids[attr->port_num - 1];
 	spin_lock_bh(&iboe->lock);
 	for (i = 0; i < MLX4_MAX_PORT_GIDS; ++i) {
 		if (!memcmp(&port_gid_table->gids[i].gid,
 			    &attr->gid, sizeof(attr->gid)) &&
-		    port_gid_table->gids[i].gid_type == attr->gid_type)  {
+		    port_gid_table->gids[i].gid_type == attr->gid_type &&
+		    port_gid_table->gids[i].vlan_id == vlan_id)  {
 			found = i;
 			break;
 		}
@@ -291,6 +297,7 @@ static int mlx4_ib_add_gid(const struct ib_gid_attr *attr, void **context)
 				memcpy(&port_gid_table->gids[free].gid,
 				       &attr->gid, sizeof(attr->gid));
 				port_gid_table->gids[free].gid_type = attr->gid_type;
+				port_gid_table->gids[free].vlan_id = vlan_id;
 				port_gid_table->gids[free].ctx->real_index = free;
 				port_gid_table->gids[free].ctx->refcount = 1;
 				hw_update = 1;

drivers/infiniband/hw/mlx4/mlx4_ib.h

@@ -508,6 +508,7 @@ struct gid_entry {
 	union ib_gid	gid;
 	enum ib_gid_type gid_type;
 	struct gid_cache_context *ctx;
+	u16 vlan_id;
 };
 
 struct mlx4_port_gid_table {