[PATCH 02/13] common/mlx5: allow ifindex query without cache

[Dariusz Sosnowski]

Translating IB port to netdev ifindex requires that cache
on mlx5 common device is initialized and RDMA monitoring
is set up. Latter happens only when ethdev mlx5 port is spawned.

To enable usage of mlx5_nl_ifindex() inside common driver code,
allow calling it without cache.
If cache is not provided, netlink query will always be executed.

Signed-off-by: Dariusz Sosnowski <dsosnowski at nvidia.com>
Acked-by: Viacheslav Ovsiienko <viacheslavo at nvidia.com>
---
 drivers/common/mlx5/linux/mlx5_nl.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/common/mlx5/linux/mlx5_nl.c b/drivers/common/mlx5/linux/mlx5_nl.c
index 1132e3fa5f..d4b40bec2c 100644
--- a/drivers/common/mlx5/linux/mlx5_nl.c
+++ b/drivers/common/mlx5/linux/mlx5_nl.c
@@ -1181,14 +1181,14 @@ mlx5_nl_port_info(int nl, uint32_t pindex, struct mlx5_nl_port_info *data)
  * when faced with port representors. Unfortunately it requires at least
  * Linux 4.17.
  *
- * @param nl
+ * @param[in] nl
  *   Netlink socket of the RDMA kind (NETLINK_RDMA).
  * @param[in] name
  *   IB device name.
  * @param[in] pindex
  *   IB device port index, starting from 1
- * @param[in] dev_info
- *   Cached mlx5 device information.
+ * @param[in,out] dev_info
+ *   Cached mlx5 device information. If NULL, netlink query is done and caching is skipped.
  * @return
  *   A valid (nonzero) interface index on success, 0 otherwise and rte_errno
  *   is set.
@@ -1206,6 +1206,9 @@ mlx5_nl_ifindex(int nl, const char *name, uint32_t pindex, struct mlx5_dev_info
 			.flags = 0,
 	};
 
+	if (dev_info == NULL)
+		goto query_port_info;
+
 	if (dev_info->probe_opt && !strcmp(name, dev_info->ibname)) {
 		if (dev_info->port_info && pindex <= dev_info->port_num &&
 		    dev_info->port_info[pindex].valid) {
@@ -1222,8 +1225,9 @@ mlx5_nl_ifindex(int nl, const char *name, uint32_t pindex, struct mlx5_dev_info
 		rte_errno = ENODEV;
 		return 0;
 	}
+query_port_info:
 	ret = mlx5_nl_port_info(nl, pindex, &data);
-	if (dev_info->probe_opt && !strcmp(dev_info->ibname, name)) {
+	if (dev_info != NULL && dev_info->probe_opt && !strcmp(dev_info->ibname, name)) {
 		if ((!ret || ret == -ENODEV) && dev_info->port_info &&
 		    pindex <= dev_info->port_num) {
 			if (!ret)
-- 
2.43.0