[RFC 04/10] net/mlx5: add multiport IB device support to probing

[Viacheslav Ovsiienko <viacheslavo@mellanox.com>]

mlx5_pci_probe() routine is refactored to probe the ports
of found Infiniband devices. All active ports (with attached
network interface), belonging to the same Infiniband device
will use the signle shared Infiniband context of that device.

Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
---
 drivers/net/mlx5/mlx5.c | 302 +++++++++++++++++++++++++++++++++---------------
 1 file changed, 210 insertions(+), 92 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index d7226fc..c6ddeb3 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -131,6 +131,16 @@
 /** Driver-specific log messages type. */
 int mlx5_logtype;
 
+/** Data associated with devices to spawn. */
+struct mlx5_dev_spawn_data {
+	uint32_t ifindex; /**< Network interface index. */
+	uint32_t max_port; /**< IB device maximal port index. */
+	uint32_t ibv_port; /**< IB device physical port index. */
+	struct mlx5_switch_info info; /**< Switch information. */
+	struct ibv_device *ibv_dev; /**< Associated IB device. */
+	struct rte_eth_dev *eth_dev; /**< Associated Ethernet device. */
+};
+
 /**
  * Prepare shared data between primary and secondary process.
  */
@@ -717,12 +727,10 @@
  *
  * @param dpdk_dev
  *   Backing DPDK device.
- * @param ibv_dev
- *   Verbs device.
+ * @param spawn
+ *   Verbs device parameters (name, port, switch_info) to spawn.
  * @param config
  *   Device configuration parameters.
- * @param[in] switch_info
- *   Switch properties of Ethernet device.
  *
  * @return
  *   A valid Ethernet device object on success, NULL otherwise and rte_errno
@@ -733,10 +741,11 @@
  */
 static struct rte_eth_dev *
 mlx5_dev_spawn(struct rte_device *dpdk_dev,
-	       struct ibv_device *ibv_dev,
-	       struct mlx5_dev_config config,
-	       const struct mlx5_switch_info *switch_info)
+	       struct mlx5_dev_spawn_data *spawn,
+	       struct mlx5_dev_config config)
 {
+	const struct mlx5_switch_info *switch_info = &spawn->info;
+	struct ibv_device *ibv_dev = spawn->ibv_dev;
 	struct ibv_context *ctx = NULL;
 	struct ibv_device_attr_ex attr;
 	struct ibv_port_attr port_attr;
@@ -950,7 +959,7 @@
 		return eth_dev;
 	}
 	/* Check port status. */
-	err = mlx5_glue->query_port(ctx, 1, &port_attr);
+	err = mlx5_glue->query_port(ctx, spawn->ibv_port, &port_attr);
 	if (err) {
 		DRV_LOG(ERR, "port query failed: %s", strerror(err));
 		goto error;
@@ -1295,14 +1304,6 @@
 	return NULL;
 }
 
-/** Data associated with devices to spawn. */
-struct mlx5_dev_spawn_data {
-	unsigned int ifindex; /**< Network interface index. */
-	struct mlx5_switch_info info; /**< Switch information. */
-	struct ibv_device *ibv_dev; /**< Associated IB device. */
-	struct rte_eth_dev *eth_dev; /**< Associated Ethernet device. */
-};
-
 /**
  * Comparison callback to sort device data.
  *
@@ -1359,7 +1360,9 @@ struct mlx5_dev_spawn_data {
 	       struct rte_pci_device *pci_dev)
 {
 	struct ibv_device **ibv_list;
-	unsigned int n = 0;
+	unsigned int nd = 0;
+	unsigned int np = 0;
+	unsigned int ns = 0;
 	struct mlx5_dev_config dev_config;
 	int ret;
 
@@ -1371,8 +1374,14 @@ struct mlx5_dev_spawn_data {
 		DRV_LOG(ERR, "cannot list devices, is ib_uverbs loaded?");
 		return -rte_errno;
 	}
-
+	/*
+	 * First scan the list of all Infiniband devices to find
+	 * matching ones, gathering into the list.
+	 */
 	struct ibv_device *ibv_match[ret + 1];
+	int nl_route = -1;
+	int nl_rdma = -1;
+	unsigned int i;
 
 	while (ret-- > 0) {
 		struct rte_pci_addr pci_addr;
@@ -1387,77 +1396,183 @@ struct mlx5_dev_spawn_data {
 			continue;
 		DRV_LOG(INFO, "PCI information matches for device \"%s\"",
 			ibv_list[ret]->name);
-		ibv_match[n++] = ibv_list[ret];
+		ibv_match[nd++] = ibv_list[ret];
+	}
+	ibv_match[nd] = NULL;
+	if (!nd) {
+		/* No device macthes, just complain and bail out. */
+		mlx5_glue->free_device_list(ibv_list);
+		DRV_LOG(WARNING,
+			"no Verbs device matches PCI device " PCI_PRI_FMT ","
+			" are kernel drivers loaded?",
+			pci_dev->addr.domain, pci_dev->addr.bus,
+			pci_dev->addr.devid, pci_dev->addr.function);
+		rte_errno = ENOENT;
+		ret = -rte_errno;
+		return ret;
+	}
+	nl_route = mlx5_nl_init(NETLINK_ROUTE);
+	nl_rdma = mlx5_nl_init(NETLINK_RDMA);
+	if (nd == 1) {
+		/*
+		 * Found single matching device may have multiple ports.
+		 * Each port may be representor, we have to check the port
+		 * number and check the representors existence.
+		 */
+		if (nl_rdma >= 0)
+			np = mlx5_nl_portnum(nl_rdma, ibv_match[0]->name);
+		if (!np)
+			DRV_LOG(WARNING, "can not get IB device \"%s\""
+					 " ports number", ibv_match[0]->name);
 	}
-	ibv_match[n] = NULL;
-
-	struct mlx5_dev_spawn_data list[n];
-	int nl_route = n ? mlx5_nl_init(NETLINK_ROUTE) : -1;
-	int nl_rdma = n ? mlx5_nl_init(NETLINK_RDMA) : -1;
-	unsigned int i;
-	unsigned int u;
-
 	/*
-	 * The existence of several matching entries (n > 1) means port
-	 * representors have been instantiated. No existing Verbs call nor
-	 * /sys entries can tell them apart, this can only be done through
-	 * Netlink calls assuming kernel drivers are recent enough to
-	 * support them.
-	 *
-	 * In the event of identification failure through Netlink, try again
-	 * through sysfs, then either:
-	 *
-	 * 1. No device matches (n == 0), complain and bail out.
-	 * 2. A single IB device matches (n == 1) and is not a representor,
-	 *    assume no switch support.
-	 * 3. Otherwise no safe assumptions can be made; complain louder and
-	 *    bail out.
+	 * Now we can determine the maximal
+	 * amount of devices to be spawned.
 	 */
-	for (i = 0; i != n; ++i) {
-		list[i].ibv_dev = ibv_match[i];
-		list[i].eth_dev = NULL;
-		if (nl_rdma < 0)
-			list[i].ifindex = 0;
-		else
-			list[i].ifindex = mlx5_nl_ifindex
-				(nl_rdma, list[i].ibv_dev->name, 1);
-		if (nl_route < 0 ||
-		    !list[i].ifindex ||
-		    mlx5_nl_switch_info(nl_route, list[i].ifindex,
-					&list[i].info) ||
-		    ((!list[i].info.representor && !list[i].info.master) &&
-		     mlx5_sysfs_switch_info(list[i].ifindex, &list[i].info))) {
-			list[i].ifindex = 0;
-			memset(&list[i].info, 0, sizeof(list[i].info));
-			continue;
+	struct mlx5_dev_spawn_data list[np ? np : nd];
+
+	if (np > 1) {
+		/*
+		 * Signle IB device with multiple ports found,
+		 * it may be E-Switch master device and representors.
+		 * We have to perform identification trough the ports.
+		 */
+		assert(nl_rdma >= 0);
+		assert(ns == 0);
+		assert(nd == 1);
+		for (i = 1; i <= np; ++i) {
+			list[ns].max_port = np;
+			list[ns].ibv_port = i;
+			list[ns].ibv_dev = ibv_match[0];
+			list[ns].eth_dev = NULL;
+			list[ns].ifindex = mlx5_nl_ifindex
+					(nl_rdma, list[ns].ibv_dev->name, i);
+			if (!list[ns].ifindex) {
+				/*
+				 * No network interface index found for the
+				 * specified port, it means there is no
+				 * representor on this port. It's OK,
+				 * there can be disabled ports, for example
+				 * if sriov_numvfs < sriov_totalvfs.
+				 */
+				continue;
+			}
+			ret = -1;
+			if (nl_route >= 0)
+				ret = mlx5_nl_switch_info
+					       (nl_route,
+						list[ns].ifindex,
+						&list[ns].info);
+			if (ret || (!list[ns].info.representor &&
+				    !list[ns].info.master)) {
+				/*
+				 * We failed to recognize representors with
+				 * Netlink, let's try to perform the task
+				 * with sysfs.
+				 */
+				ret =  mlx5_sysfs_switch_info
+						(list[ns].ifindex,
+						 &list[ns].info);
+			}
+			if (!ret && (list[ns].info.representor ^
+				     list[ns].info.master))
+				ns++;
 		}
-	}
-	if (nl_rdma >= 0)
-		close(nl_rdma);
-	if (nl_route >= 0)
-		close(nl_route);
-	/* Count unidentified devices. */
-	for (u = 0, i = 0; i != n; ++i)
-		if (!list[i].info.master && !list[i].info.representor)
-			++u;
-	if (u) {
-		if (n == 1 && u == 1) {
-			/* Case #2. */
-			DRV_LOG(INFO, "no switch support detected");
-		} else {
-			/* Case #3. */
+		if (!ns) {
+			DRV_LOG(ERR,
+				"unable to recognize master/representors"
+				" on the IB device with multiple ports");
+			rte_errno = ENOENT;
+			ret = -rte_errno;
+			goto exit;
+		}
+	} else {
+		/*
+		 * The existence of several matching entries (nd > 1) means
+		 * port representors have been instantiated. No existing Verbs
+		 * call nor sysfs entries can tell them apart, this can only
+		 * be done through Netlink calls assuming kernel drivers are
+		 * recent enough to support them.
+		 *
+		 * In the event of identification failure through Netlink,
+		 * try again through sysfs, then:
+		 *
+		 * 1. A single IB device matches (nd == 1) with single
+		 *    port (np=0/1) and is not a representor, assume
+		 *    no switch support.
+		 *
+		 * 2. Otherwise no safe assumptions can be made;
+		 *    complain louder and bail out.
+		 */
+		np = 1;
+		for (i = 0; i != nd; ++i) {
+			memset(&list[ns].info, 0, sizeof(list[ns].info));
+			list[ns].max_port = 1;
+			list[ns].ibv_port = 1;
+			list[ns].ibv_dev = ibv_match[i];
+			list[ns].eth_dev = NULL;
+			list[ns].ifindex = 0;
+			if (nl_rdma >= 0)
+				list[ns].ifindex = mlx5_nl_ifindex
+					(nl_rdma, list[ns].ibv_dev->name, 1);
+			if (!list[ns].ifindex) {
+				/*
+				 * No network interface index found for the
+				 * specified device, it means there it is not
+				 * a representor/master.
+				 */
+				continue;
+			}
+			ret = -1;
+			if (nl_route >= 0)
+				ret = mlx5_nl_switch_info
+					       (nl_route,
+						list[ns].ifindex,
+						&list[ns].info);
+			if (ret || (!list[ns].info.representor &&
+				    !list[ns].info.master)) {
+				/*
+				 * We failed to recognize representors with
+				 * Netlink, let's try to perform the task
+				 * with sysfs.
+				 */
+				ret =  mlx5_sysfs_switch_info
+						(list[ns].ifindex,
+						 &list[ns].info);
+			}
+			if (!ret && (list[ns].info.representor ^
+				     list[ns].info.master)) {
+				ns++;
+			} else if ((nd == 1) &&
+				   !list[ns].info.representor &&
+				   !list[ns].info.master) {
+				/*
+				 * Single IB device with
+				 * one physical port and
+				 * attached network device.
+				 * May be SRIOV is not enabled
+				 * or there is no representors.
+				 */
+				DRV_LOG(INFO, "no E-Switch support detected");
+				ns++;
+				break;
+			}
+		}
+		if (!ns) {
 			DRV_LOG(ERR,
-				"unable to tell which of the matching devices"
-				" is the master (lack of kernel support?)");
-			n = 0;
+				"unable to recognize master/representors"
+				" on the multiple IB devices");
+			rte_errno = ENOENT;
+			ret = -rte_errno;
+			goto exit;
 		}
 	}
+	assert(ns);
 	/*
 	 * Sort list to probe devices in natural order for users convenience
 	 * (i.e. master first, then representors from lowest to highest ID).
 	 */
-	if (n)
-		qsort(list, n, sizeof(*list), mlx5_dev_spawn_data_cmp);
+	qsort(list, ns, sizeof(*list), mlx5_dev_spawn_data_cmp);
 	/* Default configuration. */
 	dev_config = (struct mlx5_dev_config){
 		.hw_padding = 0,
@@ -1476,7 +1591,7 @@ struct mlx5_dev_spawn_data {
 			.min_rxqs_num = MLX5_MPRQ_MIN_RXQS,
 		},
 	};
-	/* Device speicific configuration. */
+	/* Device specific configuration. */
 	switch (pci_dev->id.device_id) {
 	case PCI_DEVICE_ID_MELLANOX_CONNECTX5BF:
 		dev_config.txqs_vec = MLX5_VPMD_MAX_TXQS_BLUEFIELD;
@@ -1493,12 +1608,12 @@ struct mlx5_dev_spawn_data {
 	/* Set architecture-dependent default value if unset. */
 	if (dev_config.txqs_vec == MLX5_ARG_UNSET)
 		dev_config.txqs_vec = MLX5_VPMD_MAX_TXQS;
-	for (i = 0; i != n; ++i) {
+	for (i = 0; i != ns; ++i) {
 		uint32_t restore;
 
 		list[i].eth_dev = mlx5_dev_spawn(&pci_dev->device,
-						 list[i].ibv_dev, dev_config,
-						 &list[i].info);
+						 &list[i],
+						 dev_config);
 		if (!list[i].eth_dev) {
 			if (rte_errno != EBUSY && rte_errno != EEXIST)
 				break;
@@ -1511,16 +1626,7 @@ struct mlx5_dev_spawn_data {
 		list[i].eth_dev->data->dev_flags |= restore;
 		rte_eth_dev_probing_finish(list[i].eth_dev);
 	}
-	mlx5_glue->free_device_list(ibv_list);
-	if (!n) {
-		DRV_LOG(WARNING,
-			"no Verbs device matches PCI device " PCI_PRI_FMT ","
-			" are kernel drivers loaded?",
-			pci_dev->addr.domain, pci_dev->addr.bus,
-			pci_dev->addr.devid, pci_dev->addr.function);
-		rte_errno = ENOENT;
-		ret = -rte_errno;
-	} else if (i != n) {
+	if (i != ns) {
 		DRV_LOG(ERR,
 			"probe of PCI device " PCI_PRI_FMT " aborted after"
 			" encountering an error: %s",
@@ -1542,6 +1648,18 @@ struct mlx5_dev_spawn_data {
 	} else {
 		ret = 0;
 	}
+exit:
+	/*
+	 * Do the routine cleanup:
+	 * - close opened Netlink sockets
+	 * - free the Infiniband device list
+	 */
+	if (nl_rdma >= 0)
+		close(nl_rdma);
+	if (nl_route >= 0)
+		close(nl_route);
+	assert(ibv_list);
+	mlx5_glue->free_device_list(ibv_list);
 	return ret;
 }
 
-- 
1.8.3.1