[dpdk-dev] [PATCH 1/2] common/mlx5: share kernel interface name getter

[Matan Azrad <matan@mellanox.com>]

Some configuration of the mlx5 port are done by the kernel net device
associated to the IB device represents the PCI device.

The DPDK mlx5 driver uses linux system calls, for example ioctl, in
order to configure per port configurations requested by the DPDK user.

One of the basic knowledges required to access the correct kernel net
device is its name.

Move function to get interface name from IB device path to the common
library.

Signed-off-by: Matan Azrad <matan@mellanox.com>
---
 drivers/common/mlx5/mlx5_common.c               | 88 ++++++++++++++++++++++++
 drivers/common/mlx5/mlx5_common.h               |  3 +
 drivers/common/mlx5/rte_common_mlx5_version.map |  2 +
 drivers/net/mlx5/mlx5.c                         |  2 +-
 drivers/net/mlx5/mlx5.h                         |  1 -
 drivers/net/mlx5/mlx5_ethdev.c                  | 90 +------------------------
 6 files changed, 96 insertions(+), 90 deletions(-)

diff --git a/drivers/common/mlx5/mlx5_common.c b/drivers/common/mlx5/mlx5_common.c
index 1c77763..3f0d8d3 100644
--- a/drivers/common/mlx5/mlx5_common.c
+++ b/drivers/common/mlx5/mlx5_common.c
@@ -8,8 +8,10 @@
 #ifdef RTE_IBVERBS_LINK_DLOPEN
 #include <dlfcn.h>
 #endif
+#include <dirent.h>
 
 #include <rte_errno.h>
+#include <rte_string_fns.h>
 
 #include "mlx5_common.h"
 #include "mlx5_common_utils.h"
@@ -167,6 +169,92 @@ enum mlx5_class
 	return;
 }
 
+/**
+ * Get kernel interface name from IB device path.
+ *
+ * @param[in] ibdev_path
+ *   Pointer to IB device path.
+ * @param[out] ifname
+ *   Interface name output buffer.
+ *
+ * @return
+ *   0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_get_ifname_sysfs(const char *ibdev_path, char (*ifname)[IF_NAMESIZE])
+{
+	DIR *dir;
+	struct dirent *dent;
+	unsigned int dev_type = 0;
+	unsigned int dev_port_prev = ~0u;
+	char match[IF_NAMESIZE] = "";
+
+	MLX5_ASSERT(ibdev_path);
+	{
+		MKSTR(path, "%s/device/net", ibdev_path);
+
+		dir = opendir(path);
+		if (dir == NULL) {
+			rte_errno = errno;
+			return -rte_errno;
+		}
+	}
+	while ((dent = readdir(dir)) != NULL) {
+		char *name = dent->d_name;
+		FILE *file;
+		unsigned int dev_port;
+		int r;
+
+		if ((name[0] == '.') &&
+		    ((name[1] == '\0') ||
+		     ((name[1] == '.') && (name[2] == '\0'))))
+			continue;
+
+		MKSTR(path, "%s/device/net/%s/%s",
+		      ibdev_path, name,
+		      (dev_type ? "dev_id" : "dev_port"));
+
+		file = fopen(path, "rb");
+		if (file == NULL) {
+			if (errno != ENOENT)
+				continue;
+			/*
+			 * Switch to dev_id when dev_port does not exist as
+			 * is the case with Linux kernel versions < 3.15.
+			 */
+try_dev_id:
+			match[0] = '\0';
+			if (dev_type)
+				break;
+			dev_type = 1;
+			dev_port_prev = ~0u;
+			rewinddir(dir);
+			continue;
+		}
+		r = fscanf(file, (dev_type ? "%x" : "%u"), &dev_port);
+		fclose(file);
+		if (r != 1)
+			continue;
+		/*
+		 * Switch to dev_id when dev_port returns the same value for
+		 * all ports. May happen when using a MOFED release older than
+		 * 3.0 with a Linux kernel >= 3.15.
+		 */
+		if (dev_port == dev_port_prev)
+			goto try_dev_id;
+		dev_port_prev = dev_port;
+		if (dev_port == 0)
+			strlcpy(match, name, sizeof(match));
+	}
+	closedir(dir);
+	if (match[0] == '\0') {
+		rte_errno = ENOENT;
+		return -rte_errno;
+	}
+	strncpy(*ifname, match, sizeof(*ifname));
+	return 0;
+}
+
 #ifdef MLX5_GLUE
 
 /**
diff --git a/drivers/common/mlx5/mlx5_common.h b/drivers/common/mlx5/mlx5_common.h
index 8cd3ea5..4f6373b 100644
--- a/drivers/common/mlx5/mlx5_common.h
+++ b/drivers/common/mlx5/mlx5_common.h
@@ -6,6 +6,7 @@
 #define RTE_PMD_MLX5_COMMON_H_
 
 #include <stdio.h>
+#include <net/if.h>
 
 #include <rte_pci.h>
 #include <rte_debug.h>
@@ -212,6 +213,8 @@ enum mlx5_class {
 __rte_internal
 void mlx5_translate_port_name(const char *port_name_in,
 			      struct mlx5_switch_info *port_info_out);
+__rte_internal
+int mlx5_get_ifname_sysfs(const char *ibdev_path, char (*ifname)[IF_NAMESIZE]);
 
 extern uint8_t haswell_broadwell_cpu;
 
diff --git a/drivers/common/mlx5/rte_common_mlx5_version.map b/drivers/common/mlx5/rte_common_mlx5_version.map
index b3410df..a62584d 100644
--- a/drivers/common/mlx5/rte_common_mlx5_version.map
+++ b/drivers/common/mlx5/rte_common_mlx5_version.map
@@ -33,6 +33,8 @@ INTERNAL {
 	mlx5_devx_cmd_query_virtq;
 	mlx5_devx_get_out_command_status;
 
+	mlx5_get_ifname_sysfs;
+
 	mlx5_mp_init_primary;
 	mlx5_mp_uninit_primary;
 	mlx5_mp_init_secondary;
diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 469ff73..91af47b 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -3570,7 +3570,7 @@ struct mlx5_flow_id_pool *
 					 */
 					continue;
 				}
-				ret = mlx5_get_master_ifname
+				ret = mlx5_get_ifname_sysfs
 					(ibv_match[i]->ibdev_path, &ifname);
 				if (!ret)
 					list[ns].ifindex =
diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index 2908c8b..536afae 100644
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -645,7 +645,6 @@ int mlx5_udp_tunnel_port_add(struct rte_eth_dev *dev,
 /* mlx5_ethdev.c */
 
 int mlx5_get_ifname(const struct rte_eth_dev *dev, char (*ifname)[IF_NAMESIZE]);
-int mlx5_get_master_ifname(const char *ibdev_path, char (*ifname)[IF_NAMESIZE]);
 unsigned int mlx5_ifindex(const struct rte_eth_dev *dev);
 int mlx5_ifreq(const struct rte_eth_dev *dev, int req, struct ifreq *ifr);
 int mlx5_get_mtu(struct rte_eth_dev *dev, uint16_t *mtu);
diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index b837ce6..62344d1 100644
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -129,95 +129,9 @@ struct ethtool_link_settings {
 #endif
 
 /**
- * Get master interface name from private structure.
- *
- * @param[in] dev
- *   Pointer to Ethernet device.
- * @param[out] ifname
- *   Interface name output buffer.
- *
- * @return
- *   0 on success, a negative errno value otherwise and rte_errno is set.
- */
-int
-mlx5_get_master_ifname(const char *ibdev_path, char (*ifname)[IF_NAMESIZE])
-{
-	DIR *dir;
-	struct dirent *dent;
-	unsigned int dev_type = 0;
-	unsigned int dev_port_prev = ~0u;
-	char match[IF_NAMESIZE] = "";
-
-	MLX5_ASSERT(ibdev_path);
-	{
-		MKSTR(path, "%s/device/net", ibdev_path);
-
-		dir = opendir(path);
-		if (dir == NULL) {
-			rte_errno = errno;
-			return -rte_errno;
-		}
-	}
-	while ((dent = readdir(dir)) != NULL) {
-		char *name = dent->d_name;
-		FILE *file;
-		unsigned int dev_port;
-		int r;
-
-		if ((name[0] == '.') &&
-		    ((name[1] == '\0') ||
-		     ((name[1] == '.') && (name[2] == '\0'))))
-			continue;
-
-		MKSTR(path, "%s/device/net/%s/%s",
-		      ibdev_path, name,
-		      (dev_type ? "dev_id" : "dev_port"));
-
-		file = fopen(path, "rb");
-		if (file == NULL) {
-			if (errno != ENOENT)
-				continue;
-			/*
-			 * Switch to dev_id when dev_port does not exist as
-			 * is the case with Linux kernel versions < 3.15.
-			 */
-try_dev_id:
-			match[0] = '\0';
-			if (dev_type)
-				break;
-			dev_type = 1;
-			dev_port_prev = ~0u;
-			rewinddir(dir);
-			continue;
-		}
-		r = fscanf(file, (dev_type ? "%x" : "%u"), &dev_port);
-		fclose(file);
-		if (r != 1)
-			continue;
-		/*
-		 * Switch to dev_id when dev_port returns the same value for
-		 * all ports. May happen when using a MOFED release older than
-		 * 3.0 with a Linux kernel >= 3.15.
-		 */
-		if (dev_port == dev_port_prev)
-			goto try_dev_id;
-		dev_port_prev = dev_port;
-		if (dev_port == 0)
-			strlcpy(match, name, sizeof(match));
-	}
-	closedir(dir);
-	if (match[0] == '\0') {
-		rte_errno = ENOENT;
-		return -rte_errno;
-	}
-	strncpy(*ifname, match, sizeof(*ifname));
-	return 0;
-}
-
-/**
  * Get interface name from private structure.
  *
- * This is a port representor-aware version of mlx5_get_master_ifname().
+ * This is a port representor-aware version of mlx5_get_ifname_sysfs().
  *
  * @param[in] dev
  *   Pointer to Ethernet device.
@@ -238,7 +152,7 @@ struct ethtool_link_settings {
 	ifindex = mlx5_ifindex(dev);
 	if (!ifindex) {
 		if (!priv->representor)
-			return mlx5_get_master_ifname(priv->sh->ibdev_path,
+			return mlx5_get_ifname_sysfs(priv->sh->ibdev_path,
 						      ifname);
 		rte_errno = ENXIO;
 		return -rte_errno;
-- 
1.8.3.1