[PATCH v10 4/8] net/nfb: add device argument "port" to limit used ports

[spinler@cesnet.cz]

From: Martin Spinler <spinler@cesnet.cz>

NFB devices do not use separate PCI device for each port; one PCI device
contains handles for all ports instead. For some application this approach
can be limiting.

The "port" argument can be used to select only desired ports.
It can be used multiple times. When is not used at all, the driver
selects all ports.

Signed-off-by: Martin Spinler <spinler@cesnet.cz>
---
 drivers/net/nfb/nfb.h        |  7 ++++
 drivers/net/nfb/nfb_ethdev.c | 71 ++++++++++++++++++++++++++++++++++--
 drivers/net/nfb/nfb_vdev.c   |  3 +-
 3 files changed, 76 insertions(+), 5 deletions(-)

diff --git a/drivers/net/nfb/nfb.h b/drivers/net/nfb/nfb.h
index a854d16426..22fcb68cd7 100644
--- a/drivers/net/nfb/nfb.h
+++ b/drivers/net/nfb/nfb.h
@@ -42,6 +42,13 @@ extern int nfb_logtype;
 
 #define RTE_NFB_DRIVER_NAME net_nfb
 
+/* Device arguments */
+#define NFB_ARG_PORT "port"
+
+#define NFB_COMMON_ARGS \
+	NFB_ARG_PORT "=<number>" \
+	""
+
 /*
  * Handles obtained from the libnfb: each process must use own instance.
  * Stored inside dev->process_private.
diff --git a/drivers/net/nfb/nfb_ethdev.c b/drivers/net/nfb/nfb_ethdev.c
index 233eb91e18..706b90bae5 100644
--- a/drivers/net/nfb/nfb_ethdev.c
+++ b/drivers/net/nfb/nfb_ethdev.c
@@ -4,6 +4,7 @@
  * All rights reserved.
  */
 
+#include <ctype.h>
 #include <sys/queue.h>
 #include <eal_export.h>
 #include <rte_tailq.h>
@@ -22,12 +23,19 @@
 #include "nfb_rxmode.h"
 #include "nfb.h"
 
+static const char * const VALID_KEYS[] = {
+	NFB_ARG_PORT,
+	NULL
+};
+
 struct nfb_ifc_create_params {
 	struct nfb_probe_params *probe_params;
 	struct nc_ifc_map_info map_info;
 	struct nc_ifc_info *ifc_info;
 
 	int basename_len;       /* Cached real length of original probe_params->name */
+	/* Return value of failed nfb_eth_dev_create_for_ifc when rte_kvargs_process is used */
+	int ret;
 };
 
 /* The TAILQ entries are used for cleanup of allocated resources
@@ -738,6 +746,33 @@ nfb_eth_dev_create_for_ifc(struct nfb_ifc_create_params *cp)
 	return ret;
 }
 
+static int nfb_eth_dev_create_for_ifc_by_port(const char *key __rte_unused,
+		const char *value, void *opaque)
+{
+	int ret = -EINVAL;
+	char *end;
+	unsigned long port;
+	struct nfb_ifc_create_params *ifc_params = opaque;
+
+	if (value == NULL || strlen(value) == 0 || !isdigit(*value))
+		goto out;
+
+	errno = 0;
+	port = strtoul(value, &end, 10);
+	if (errno != 0 || *end != '\0')
+		goto out;
+
+	if (port >= LONG_MAX || port >= (unsigned long)ifc_params->map_info.ifc_cnt)
+		goto out;
+
+	ifc_params->ifc_info = &ifc_params->map_info.ifc[port];
+	ret = nfb_eth_dev_create_for_ifc(ifc_params);
+
+out:
+	ifc_params->ret = ret;
+	return ret;
+}
+
 int
 nfb_eth_common_probe(struct nfb_probe_params *params)
 {
@@ -746,6 +781,7 @@ nfb_eth_common_probe(struct nfb_probe_params *params)
 
 	struct nfb_device *nfb_dev;
 	struct nfb_ifc_create_params ifc_params;
+	struct rte_kvargs *kvlist = NULL;
 
 	/* Open the device handle just for parsing ifc_params.
 	 * A separate handle is used later for each netdev.
@@ -760,16 +796,38 @@ nfb_eth_common_probe(struct nfb_probe_params *params)
 	if (ret)
 		goto err_map_info_create;
 
+	if (params->args != NULL && strlen(params->args) > 0) {
+		kvlist = rte_kvargs_parse(params->args, VALID_KEYS);
+		if (kvlist == NULL) {
+			NFB_LOG(ERR, "Failed to parse device arguments %s", params->args);
+			ret = -EINVAL;
+			goto err_parse_args;
+		}
+	}
+
+	ifc_params.ret = 0;
 	ifc_params.probe_params = params;
 	ifc_params.basename_len = strlen(params->name);
 
-	for (i = 0; i < ifc_params.map_info.ifc_cnt; i++) {
-		ifc_params.ifc_info = &ifc_params.map_info.ifc[i];
-		ret = nfb_eth_dev_create_for_ifc(&ifc_params);
-		if (ret)
+	/* When at least one port argument is specified, create only selected ports */
+	if (kvlist && rte_kvargs_count(kvlist, NFB_ARG_PORT)) {
+		ret = rte_kvargs_process(kvlist, NFB_ARG_PORT,
+				nfb_eth_dev_create_for_ifc_by_port, (void *)&ifc_params);
+		if (ret) {
+			ret = ifc_params.ret;
 			goto err_dev_create;
+		}
+	} else {
+		for (i = 0; i < ifc_params.map_info.ifc_cnt; i++) {
+			ifc_params.ifc_info = &ifc_params.map_info.ifc[i];
+			ret = nfb_eth_dev_create_for_ifc(&ifc_params);
+			if (ret)
+				goto err_dev_create;
+		}
 	}
 
+	rte_kvargs_free(kvlist);
+
 	nc_map_info_destroy(&ifc_params.map_info);
 	nfb_close(nfb_dev);
 
@@ -777,6 +835,8 @@ nfb_eth_common_probe(struct nfb_probe_params *params)
 
 err_dev_create:
 	nfb_eth_common_remove(params->device);
+	rte_kvargs_free(kvlist);
+err_parse_args:
 	nc_map_info_destroy(&ifc_params.map_info);
 err_map_info_create:
 	nfb_close(nfb_dev);
@@ -882,3 +942,6 @@ RTE_PMD_REGISTER_PCI(RTE_NFB_DRIVER_NAME, nfb_eth_driver);
 RTE_PMD_REGISTER_PCI_TABLE(RTE_NFB_DRIVER_NAME, nfb_pci_id_table);
 RTE_PMD_REGISTER_KMOD_DEP(RTE_NFB_DRIVER_NAME, "* nfb");
 RTE_LOG_REGISTER_DEFAULT(nfb_logtype, NOTICE);
+RTE_PMD_REGISTER_PARAM_STRING(RTE_NFB_DRIVER_NAME,
+		NFB_COMMON_ARGS
+		);
diff --git a/drivers/net/nfb/nfb_vdev.c b/drivers/net/nfb/nfb_vdev.c
index b79f7ac416..57f10d2068 100644
--- a/drivers/net/nfb/nfb_vdev.c
+++ b/drivers/net/nfb/nfb_vdev.c
@@ -102,5 +102,6 @@ static struct rte_vdev_driver vdev_nfb_vdev = {
 RTE_PMD_REGISTER_VDEV(VDEV_NFB_DRIVER, vdev_nfb_vdev);
 RTE_PMD_REGISTER_ALIAS(VDEV_NFB_DRIVER, eth_vdev_nfb);
 RTE_PMD_REGISTER_PARAM_STRING(net_vdev_nfb,
-		VDEV_NFB_ARG_DEV "=<string>"
+		VDEV_NFB_ARG_DEV "=<string> "
+		NFB_COMMON_ARGS
 		);
-- 
2.53.0