[dpdk-dev] [PATCH v2 11/25] mlx5: add support for configuration through kvargs

[Nelio Laranjeiro <nelio.laranjeiro@6wind.com>]

The intent is to replace the remaining compile-time options and environment
variables with a common mean of runtime configuration. This commit only
adds the kvargs handling code, subsequent commits will update the rest.

Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
---
 drivers/net/mlx5/mlx5.c | 72 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 72 insertions(+)

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 3f45d84..56b1dfc 100644
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -37,6 +37,7 @@
 #include <assert.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <errno.h>
 #include <net/if.h>
 
 /* Verbs header. */
@@ -57,6 +58,7 @@
 #include <rte_ethdev.h>
 #include <rte_pci.h>
 #include <rte_common.h>
+#include <rte_kvargs.h>
 #ifdef PEDANTIC
 #pragma GCC diagnostic error "-pedantic"
 #endif
@@ -237,6 +239,70 @@ mlx5_dev_idx(struct rte_pci_addr *pci_addr)
 	return ret;
 }
 
+/**
+ * Verify and store value for device argument.
+ *
+ * @param[in] key
+ *   Key argument to verify.
+ * @param[in] val
+ *   Value associated with key.
+ * @param opaque
+ *   User data.
+ *
+ * @return
+ *   0 on success, errno value on failure.
+ */
+static int
+mlx5_args_check(const char *key, const char *val, void *opaque)
+{
+	struct priv *priv = opaque;
+
+	/* No parameters are expected at the moment. */
+	(void)priv;
+	(void)val;
+	WARN("%s: unknown parameter", key);
+	return EINVAL;
+}
+
+/**
+ * Parse device parameters.
+ *
+ * @param priv
+ *   Pointer to private structure.
+ * @param devargs
+ *   Device arguments structure.
+ *
+ * @return
+ *   0 on success, errno value on failure.
+ */
+static int
+mlx5_args(struct priv *priv, struct rte_devargs *devargs)
+{
+	static const char *params[] = {
+		NULL,
+	};
+	struct rte_kvargs *kvlist;
+	int ret = 0;
+	int i;
+
+	if (devargs == NULL)
+		return 0;
+	kvlist = rte_kvargs_parse(devargs->args, params);
+	if (kvlist == NULL)
+		return 0;
+	/* Process parameters. */
+	for (i = 0; (i != RTE_DIM(params)); ++i) {
+		if (rte_kvargs_count(kvlist, params[i])) {
+			ret = rte_kvargs_process(kvlist, params[i],
+						 mlx5_args_check, priv);
+			if (ret != 0)
+				return ret;
+		}
+	}
+	rte_kvargs_free(kvlist);
+	return 0;
+}
+
 static struct eth_driver mlx5_driver;
 
 /**
@@ -408,6 +474,12 @@ mlx5_pci_devinit(struct rte_pci_driver *pci_drv, struct rte_pci_device *pci_dev)
 		priv->port = port;
 		priv->pd = pd;
 		priv->mtu = ETHER_MTU;
+		err = mlx5_args(priv, pci_dev->devargs);
+		if (err) {
+			ERROR("failed to process device arguments: %s",
+			      strerror(err));
+			goto port_error;
+		}
 		if (ibv_exp_query_device(ctx, &exp_device_attr)) {
 			ERROR("ibv_exp_query_device() failed");
 			goto port_error;
-- 
2.1.4