[dpdk-dev] [PATCH v2 07/41] common/mlx5: retrieve the device index and name

[Srikanth Kaka]

The mlx5_core kernel driver creates a sysctl variable
dev.mlx5_core.0.ifname: mce0

Using this the device index and interface name are obtained
The interface name can be used by PMD to communicate with
FreeBSD network stack

Signed-off-by: Srikanth Kaka <srikant...@oneconvergence.com>
Signed-off-by: Vag Singh <vag.si...@oneconvergence.com>
Signed-off-by: Anand Thulasiram <av...@juniper.net>
---
 drivers/common/mlx5/freebsd/mlx5_common_os.c | 44 ++++++++++++++++++++
 drivers/common/mlx5/freebsd/mlx5_common_os.h |  6 +++
 2 files changed, 50 insertions(+)

diff --git a/drivers/common/mlx5/freebsd/mlx5_common_os.c 
b/drivers/common/mlx5/freebsd/mlx5_common_os.c
index 9c3cd1e4e6..23370857eb 100644
--- a/drivers/common/mlx5/freebsd/mlx5_common_os.c
+++ b/drivers/common/mlx5/freebsd/mlx5_common_os.c
@@ -4,14 +4,58 @@
 
 #include <unistd.h>
 #include <stdio.h>
+#include <net/if.h>
 #include <sys/sysctl.h>
 
 #include <rte_errno.h>
 
 #include "mlx5_common.h"
 #include "mlx5_common_log.h"
+#include "mlx5_common_os.h"
 #include "mlx5_glue.h"
 
+/**
+ * Derive IB dev index from devpath
+ */
+int
+mlx5_get_ibvindex(const char *ibdev_path)
+{
+       unsigned int ibv_idx;
+
+       MLX5_ASSERT(ibdev_path);
+       if (sscanf(ibdev_path, "/sys/class/infiniband/mlx5_%u",
+                  &ibv_idx) != 1)
+               ibv_idx = -1;
+
+       return ibv_idx;
+}
+
+int
+mlx5_get_ifname_sysfs(const char *ibdev_path, char *ifname)
+{
+       char buffer[MLX5_SYSCTL_BY_NAME_SIZE];
+       char name[IF_NAMESIZE];
+       size_t len = IF_NAMESIZE;
+       unsigned int idx;
+
+       idx = mlx5_get_ibvindex(ibdev_path);
+       if (idx < 0) {
+               rte_errno = EINVAL;
+               return -rte_errno;
+       }
+
+       snprintf(buffer, sizeof(buffer), "dev.mlx5_core.%u.ifname", idx);
+       if (sysctlbyname(buffer, &name, &len, NULL, 0)) {
+               DRV_LOG(ERR, "port %u failed to get interface name: %s",
+                       idx, strerror(errno));
+               rte_errno = errno;
+               return -rte_errno;
+       }
+       strncpy(ifname, name, IF_NAMESIZE);
+
+       return 0;
+}
+
 /**
  * Initialization routine for run-time dependency on rdma-core.
  */
diff --git a/drivers/common/mlx5/freebsd/mlx5_common_os.h 
b/drivers/common/mlx5/freebsd/mlx5_common_os.h
index dab67ecbf0..60e7c4f21f 100644
--- a/drivers/common/mlx5/freebsd/mlx5_common_os.h
+++ b/drivers/common/mlx5/freebsd/mlx5_common_os.h
@@ -18,6 +18,8 @@
 #include "mlx5_autoconf.h"
 #include "mlx5_glue.h"
 
+#define MLX5_SYSCTL_BY_NAME_SIZE 100
+
 /**
  * Get device name. Given an ibv_device pointer - return a
  * pointer to the corresponding device name.
@@ -287,4 +289,8 @@ mlx5_os_free(void *addr)
 {
        free(addr);
 }
+
+int
+mlx5_get_ibvindex(const char *ibdev_path);
+
 #endif /* RTE_PMD_MLX5_COMMON_OS_H_ */
-- 
2.30.2