prov/verbs: fi_getinfo() returns fi_sockaddr_ib interfaces.

This is the final patch of the series that adds the support
of GID-base connection establishment.

The Verbs provider now can directly connect to the network
adapters using the GID. In other words, the patch allows
to use Libfabric even if there is no IP address set for the
Infiniband interfaces.

There are significant issues of issues IP addresses for connection
establishment:
- It requires to set up/maintain IP addresses for every IB interfaces.
- In the context of multirail (multiple local interfaces that belong
  to the same network subnet), it requires specific IP routes to
  prevent an interface to reply for another one. Connection
  establishment would fail otherwise.

The GID can be accessed  by looking at the field src_addr returned
by "fi_info -p verbs -v".

Example of output:
src_addr: fi_sockaddr_ib://[fe80::248a:703:1c:dc0c]:ffff:13f:0

The patch also modifies fabtest so anybody can start testing this
new feature. A new option -F allows to specify the address format
that is use for the source/destination addresses.

After figuring out the GID of interface that will be used for the
server, one can run the following commands with fabtest:

Server:
fi_msg_bw -s [fe80::248a:703:1c:dc0c]:ffff:13f:0 -e msg \
-p verbs -F fi_sockaddr_ib

Client:
fi_msg_bw -e msg -p verbs \
-F fi_sockaddr_ib [fe80::248a:703:1c:dc0c]:ffff:13f:0

Signed-off-by: Sylvain Didelot <sdidelot@ddn.com>

prov/verbs/src/fi_verbs.c

@@ -103,7 +103,7 @@ int vrb_sockaddr_len(struct sockaddr *addr)
 }
 
 static int
-vrb_get_rdma_rai(const char *node, const char *service, uint64_t flags,
+vrb_get_rdmacm_rai(const char *node, const char *service, uint64_t flags,
 		 const struct fi_info *hints, struct rdma_addrinfo **rai)
 {
 	struct rdma_addrinfo rai_hints, *_rai;
@@ -154,6 +154,73 @@ vrb_get_rdma_rai(const char *node, const char *service, uint64_t flags,
 	return ret;
 }
 
+static int vrb_get_sib_rai(const char *node, const char *service, uint64_t flags,
+		      const struct fi_info *hints, struct rdma_addrinfo **rai)
+{
+	struct sockaddr_ib *sib;
+	size_t sib_len;
+	char *straddr;
+	uint32_t fmt;
+	int ret;
+	bool has_prefix;
+	const char *prefix = "fi_sockaddr_ib://";
+
+	if (!node)
+		return -FI_EINVAL;
+
+	fmt = ofi_addr_format(node);
+	if (fmt == FI_SOCKADDR_IB)
+		has_prefix = true;
+	else if (fmt == FI_FORMAT_UNSPEC)
+		has_prefix = false;
+	else
+		return -FI_EINVAL;
+
+	if (service) {
+		asprintf(&straddr, "%s%s:%s", has_prefix ? "" : prefix, node, service);
+	} else {
+		asprintf(&straddr, "%s%s", has_prefix ? "" : prefix, node);
+	}
+
+	ret = ofi_str_toaddr(straddr, &fmt, (void **)&sib, &sib_len);
+	free(straddr);
+
+	if (ret || fmt != FI_SOCKADDR_IB) {
+		return -FI_EINVAL;
+	}
+
+	*rai = calloc(1, sizeof(struct rdma_addrinfo));
+	if (*rai == NULL)
+		return -FI_ENOMEM;
+
+	(*rai)->ai_family = AF_IB;
+	(*rai)->ai_port_space = RDMA_PS_IB;
+	(*rai)->ai_qp_type = IBV_QPT_RC;
+
+	if (flags & FI_SOURCE) {
+		(*rai)->ai_flags |= RAI_PASSIVE;
+		(*rai)->ai_src_addr = (void *)sib;
+		(*rai)->ai_src_len = sizeof(struct sockaddr_ib);
+	} else {
+		(*rai)->ai_dst_addr = (void *)sib;
+		(*rai)->ai_dst_len = sizeof(struct sockaddr_ib);
+	}
+
+	ofi_straddr_log(&vrb_prov, FI_LOG_INFO, FI_LOG_FABRIC,
+			"src addr", sib);
+
+	return 0;
+}
+
+int vrb_get_rdma_rai(const char *node, const char *service, uint64_t flags,
+		      const struct fi_info *hints, struct rdma_addrinfo **rai)
+{
+	if (node && hints && hints->addr_format == FI_SOCKADDR_IB)
+		return vrb_get_sib_rai(node, service, flags, hints, rai);
+	else
+		return vrb_get_rdmacm_rai(node, service, flags, hints, rai);
+}
+
 int vrb_get_rai_id(const char *node, const char *service, uint64_t flags,
 		      const struct fi_info *hints, struct rdma_addrinfo **rai,
 		      struct rdma_cm_id **id)