[dpdk-dev] [PATCH v5] net/mlx5: support new representor naming format

[Dekel Peled <dekelp@mellanox.com>]

Kernel update [1] introduce new format of representors names.
This patch implements RFC [2], updating MLX5 PMD to support the new
format, while maintaining support of the existing format.

[1] https://github.com/torvalds/linux/commit/c12ecc2
[2] http://mails.dpdk.org/archives/dev/2019-March/125676.html

Signed-off-by: Dekel Peled <dekelp@mellanox.com>

---
v5: Add flag to indicate if rep. port name is in new format.
v4: Remove redundant clear of errno.
v3: Add utility function with common logic, call it from sysfs and nl.
v2: Use public link to kernel patch, add link to RFC.
---
---
 drivers/net/mlx5/mlx5.h        |  3 +++
 drivers/net/mlx5/mlx5_ethdev.c | 54 ++++++++++++++++++++++++++++++++++++++----
 drivers/net/mlx5/mlx5_nl.c     | 11 ++++-----
 3 files changed, 57 insertions(+), 11 deletions(-)

diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index 5384453..88ffb19 100644
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -60,6 +60,7 @@ enum {
 struct mlx5_switch_info {
 	uint32_t master:1; /**< Master device. */
 	uint32_t representor:1; /**< Representor device. */
+	uint32_t port_name_new:1; /**< Rep. port name is in new format. */
 	int32_t port_name; /**< Representor port name. */
 	uint64_t switch_id; /**< Switch identifier. */
 };
@@ -300,6 +301,8 @@ unsigned int mlx5_dev_to_port_id(const struct rte_device *dev,
 				 unsigned int port_list_n);
 int mlx5_sysfs_switch_info(unsigned int ifindex,
 			   struct mlx5_switch_info *info);
+bool mlx5_translate_port_name(const char *port_name_in,
+			      struct mlx5_switch_info *port_info_out);
 
 /* mlx5_mac.c */
 
diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index 795c9c7..428a465 100644
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -1353,9 +1353,16 @@ int mlx5_fw_version_get(struct rte_eth_dev *dev, char *fw_ver, size_t fw_size)
 mlx5_sysfs_switch_info(unsigned int ifindex, struct mlx5_switch_info *info)
 {
 	char ifname[IF_NAMESIZE];
+	char port_name[IF_NAMESIZE];
 	FILE *file;
 	DIR *dir;
-	struct mlx5_switch_info data = { .master = 0, };
+	struct mlx5_switch_info data = {
+		.master = 0,
+		.representor = 0,
+		.port_name_new = 0,
+		.port_name = 0,
+		.switch_id = 0,
+	};
 	bool port_name_set = false;
 	bool port_switch_id_set = false;
 	bool device_dir = false;
@@ -1375,10 +1382,9 @@ int mlx5_fw_version_get(struct rte_eth_dev *dev, char *fw_ver, size_t fw_size)
 
 	file = fopen(phys_port_name, "rb");
 	if (file != NULL) {
-		port_name_set =
-			fscanf(file, "%d%c", &data.port_name, &c) == 2 &&
-			c == '\n';
+		fscanf(file, "%s", port_name);
 		fclose(file);
+		port_name_set = mlx5_translate_port_name(port_name, &data);
 	}
 	file = fopen(phys_switch_id, "rb");
 	if (file == NULL) {
@@ -1399,3 +1405,43 @@ int mlx5_fw_version_get(struct rte_eth_dev *dev, char *fw_ver, size_t fw_size)
 	*info = data;
 	return 0;
 }
+
+/**
+ * Extract port name, as a number, from sysfs or netlink information.
+ *
+ * @param[in] port_name_in
+ *   String representing the port name.
+ * @param[out] port_info_out
+ *   Port information, including port name as a number.
+ *
+ * @return
+ *   true on success, false otherwise.
+ */
+bool
+mlx5_translate_port_name(const char *port_name_in,
+			 struct mlx5_switch_info *port_info_out)
+{
+	char pf_c1, pf_c2, vf_c1, vf_c2;
+	char *end;
+	int32_t pf_num;
+	bool port_name_set = false;
+
+	/*
+	 * Check for port-name as a string of the form pf0vf0
+	 * (support kernel ver >= 5.0)
+	 */
+	port_name_set =	(sscanf(port_name_in, "%c%c%d%c%c%d", &pf_c1, &pf_c2,
+				&pf_num, &vf_c1, &vf_c2,
+				&port_info_out->port_name) == 6);
+	if (port_name_set) {
+		port_info_out->port_name_new = 1;
+	} else {
+		/* Check for port-name as a number (support kernel ver < 5.0 */
+		errno = 0;
+		port_info_out->port_name = strtol(port_name_in, &end, 0);
+		if (!errno &&
+		    (size_t)(end - port_name_in) == strlen(port_name_in))
+			port_name_set = true;
+	}
+	return port_name_set;
+}
diff --git a/drivers/net/mlx5/mlx5_nl.c b/drivers/net/mlx5/mlx5_nl.c
index 0bf6845..cb34de3 100644
--- a/drivers/net/mlx5/mlx5_nl.c
+++ b/drivers/net/mlx5/mlx5_nl.c
@@ -836,6 +836,7 @@ struct mlx5_nl_ifindex_data {
 	struct mlx5_switch_info info = {
 		.master = 0,
 		.representor = 0,
+		.port_name_new = 0,
 		.port_name = 0,
 		.switch_id = 0,
 	};
@@ -849,7 +850,6 @@ struct mlx5_nl_ifindex_data {
 	while (off < nh->nlmsg_len) {
 		struct rtattr *ra = (void *)((uintptr_t)nh + off);
 		void *payload = RTA_DATA(ra);
-		char *end;
 		unsigned int i;
 
 		if (ra->rta_len > nh->nlmsg_len - off)
@@ -859,12 +859,9 @@ struct mlx5_nl_ifindex_data {
 			num_vf_set = true;
 			break;
 		case IFLA_PHYS_PORT_NAME:
-			errno = 0;
-			info.port_name = strtol(payload, &end, 0);
-			if (errno ||
-			    (size_t)(end - (char *)payload) != strlen(payload))
-				goto error;
-			port_name_set = true;
+			port_name_set =
+				mlx5_translate_port_name((char *)payload,
+							 &info);
 			break;
 		case IFLA_PHYS_SWITCH_ID:
 			info.switch_id = 0;
-- 
1.8.3.1