[dpdk-dev] [PATCH v3 4/5] bus: add device arguments name parsing API

[Xueming Li]

To use Global Device Syntax as devargs, name is required for device
management.

In legacy parsing API, devargs name was extracted after bus name:
  bus:name,kv_params,,,

To parse new Global Device Syntax, this patch introduces new bus API to
parse devargs and update name, different bus driver might choose
different keys from parameters with unified formating, example:
 -a bus=pci,addr=83:00.0/class=eth/driver=mlx5,...
    name: 0000:03:00.0
 -a bus=vdev,name=pcap0/class=eth/driver=pcap,...
    name:pcap0

Signed-off-by: Xueming Li <xuemingl at nvidia.com>
---
 drivers/bus/pci/pci_common.c               |  1 +
 drivers/bus/pci/pci_params.c               | 48 ++++++++++++++++++++++
 drivers/bus/pci/private.h                  | 14 +++++++
 drivers/bus/vdev/vdev.c                    |  1 +
 drivers/bus/vdev/vdev_params.c             | 43 +++++++++++++++++++
 drivers/bus/vdev/vdev_private.h            | 15 +++++++
 lib/librte_eal/common/eal_common_devargs.c |  6 +++
 lib/librte_eal/include/rte_bus.h           | 19 +++++++++
 8 files changed, 147 insertions(+)

diff --git a/drivers/bus/pci/pci_common.c b/drivers/bus/pci/pci_common.c
index 9b8d769287..61d3f51452 100644
--- a/drivers/bus/pci/pci_common.c
+++ b/drivers/bus/pci/pci_common.c
@@ -760,6 +760,7 @@ struct rte_pci_bus rte_pci_bus = {
 		.dev_iterate = rte_pci_dev_iterate,
 		.hot_unplug_handler = pci_hot_unplug_handler,
 		.sigbus_handler = pci_sigbus_handler,
+		.devargs_parse = rte_pci_devargs_parse,
 	},
 	.device_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.device_list),
 	.driver_list = TAILQ_HEAD_INITIALIZER(rte_pci_bus.driver_list),
diff --git a/drivers/bus/pci/pci_params.c b/drivers/bus/pci/pci_params.c
index 3192e9c967..7ba9e2650f 100644
--- a/drivers/bus/pci/pci_params.c
+++ b/drivers/bus/pci/pci_params.c
@@ -8,6 +8,8 @@
 #include <rte_errno.h>
 #include <rte_kvargs.h>
 #include <rte_pci.h>
+#include <rte_devargs.h>
+#include <rte_debug.h>
 
 #include "private.h"
 
@@ -76,3 +78,49 @@ rte_pci_dev_iterate(const void *start,
 	rte_kvargs_free(kvargs);
 	return dev;
 }
+
+int
+rte_pci_devargs_parse(struct rte_devargs *da)
+{
+	struct rte_kvargs *kvargs;
+	const char *addr_str;
+	struct rte_pci_addr addr;
+	int ret;
+
+	if (da == NULL)
+		return 0;
+	RTE_ASSERT(da->bus_str != NULL);
+
+	kvargs = rte_kvargs_parse(da->bus_str, NULL);
+	if (kvargs == NULL) {
+		RTE_LOG(ERR, EAL, "cannot parse argument list: %s\n",
+			da->bus_str);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	addr_str = rte_kvargs_get(kvargs, pci_params_keys[RTE_PCI_PARAM_ADDR]);
+	if (addr_str == NULL) {
+		RTE_LOG(ERR, EAL, "No PCI address specified using '%s=<id>' in: %s\n",
+			pci_params_keys[RTE_PCI_PARAM_ADDR], da->bus_str);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	ret = rte_pci_addr_parse(addr_str, &addr);
+	if (ret != 0) {
+		RTE_LOG(ERR, EAL, "PCI address invalid: %s\n", da->bus_str);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	rte_pci_device_name(&addr, da->name, sizeof(da->name));
+
+	/* TODO: class parse -> driver parse */
+out:
+	if (kvargs != NULL)
+		rte_kvargs_free(kvargs);
+	if (ret != 0)
+		rte_errno = -ret;
+	return ret;
+}
diff --git a/drivers/bus/pci/private.h b/drivers/bus/pci/private.h
index f566943f5e..8bc5140e97 100644
--- a/drivers/bus/pci/private.h
+++ b/drivers/bus/pci/private.h
@@ -267,4 +267,18 @@ rte_pci_dev_iterate(const void *start,
 		    const char *str,
 		    const struct rte_dev_iterator *it);
 
+/*
+ * Parse device arguments and update name.
+ *
+ * @param da
+ *   device arguments to parse.
+ *
+ * @return
+ *   0 on success.
+ *   -EINVAL: kvargs string is invalid and cannot be parsed.
+ *   -ENODEV: no key matching a device ID is found in the kv list.
+ */
+int
+rte_pci_devargs_parse(struct rte_devargs *da);
+
 #endif /* _PCI_PRIVATE_H_ */
diff --git a/drivers/bus/vdev/vdev.c b/drivers/bus/vdev/vdev.c
index d075409942..d6f651bff2 100644
--- a/drivers/bus/vdev/vdev.c
+++ b/drivers/bus/vdev/vdev.c
@@ -634,6 +634,7 @@ static struct rte_bus rte_vdev_bus = {
 	.dma_unmap = vdev_dma_unmap,
 	.get_iommu_class = vdev_get_iommu_class,
 	.dev_iterate = rte_vdev_dev_iterate,
+	.devargs_parse = rte_vdev_devargs_parse,
 };
 
 RTE_REGISTER_BUS(vdev, rte_vdev_bus);
diff --git a/drivers/bus/vdev/vdev_params.c b/drivers/bus/vdev/vdev_params.c
index 6f74704d1c..3e644ade95 100644
--- a/drivers/bus/vdev/vdev_params.c
+++ b/drivers/bus/vdev/vdev_params.c
@@ -8,6 +8,9 @@
 #include <rte_bus.h>
 #include <rte_kvargs.h>
 #include <rte_errno.h>
+#include <rte_devargs.h>
+#include <rte_string_fns.h>
+#include <rte_debug.h>
 
 #include "vdev_logs.h"
 #include "vdev_private.h"
@@ -64,3 +67,43 @@ rte_vdev_dev_iterate(const void *start,
 	rte_kvargs_free(kvargs);
 	return dev;
 }
+
+int
+rte_vdev_devargs_parse(struct rte_devargs *da)
+{
+	struct rte_kvargs *kvargs;
+	const char *name;
+	int ret = 0;
+
+	if (da == NULL)
+		return 0;
+	RTE_ASSERT(da->bus_str != NULL);
+
+	kvargs = rte_kvargs_parse(da->bus_str, NULL);
+	if (kvargs == NULL) {
+		RTE_LOG(ERR, EAL, "cannot parse argument list: %s\n",
+			da->bus_str);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	name = rte_kvargs_get(kvargs, vdev_params_keys[RTE_VDEV_PARAM_NAME]);
+	if (name == NULL) {
+		RTE_LOG(ERR, EAL, "name not found: %s\n", da->bus_str);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	if (rte_strscpy(da->name, name, sizeof(da->name)) < 0) {
+		RTE_LOG(ERR, EAL, "device name is too long: %s\n", name);
+		ret = -E2BIG;
+	}
+
+	/* TODO: class parse -> driver parse */
+out:
+	if (kvargs != NULL)
+		rte_kvargs_free(kvargs);
+	if (ret != 0)
+		rte_errno = -ret;
+	return ret;
+}
diff --git a/drivers/bus/vdev/vdev_private.h b/drivers/bus/vdev/vdev_private.h
index ba6dc48ff3..257682daac 100644
--- a/drivers/bus/vdev/vdev_private.h
+++ b/drivers/bus/vdev/vdev_private.h
@@ -19,6 +19,21 @@ rte_vdev_dev_iterate(const void *start,
 		     const char *str,
 		     const struct rte_dev_iterator *it);
 
+/*
+ * Parse device argument and update name.
+ *
+ * @param da
+ *   device argument to parse.
+ *
+ * @return
+ *   0 on success.
+ *   -EINVAL: kvargs string is invalid and cannot be parsed.
+ *   -ENODEV: no key matching a device ID is found in the kv list.
+ *   -E2BIG: device name is too long.
+ */
+int
+rte_vdev_devargs_parse(struct rte_devargs *da);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/common/eal_common_devargs.c b/lib/librte_eal/common/eal_common_devargs.c
index e40b91ea66..b4dcb0099c 100644
--- a/lib/librte_eal/common/eal_common_devargs.c
+++ b/lib/librte_eal/common/eal_common_devargs.c
@@ -118,6 +118,8 @@ rte_devargs_layers_parse(struct rte_devargs *devargs,
 		if (layers[i].kvlist == NULL)
 			continue;
 		kv = &layers[i].kvlist->pairs[0];
+		if (!kv->key)
+			continue;
 		if (strcmp(kv->key, "bus") == 0) {
 			bus = rte_bus_find_by_name(kv->value);
 			if (bus == NULL) {
@@ -160,6 +162,10 @@ rte_devargs_layers_parse(struct rte_devargs *devargs,
 		}
 	}
 
+	/* Parse device name, optional for iterator filter. */
+	if (bus && bus->devargs_parse)
+		bus->devargs_parse(devargs);
+
 get_out:
 	for (i = 0; i < RTE_DIM(layers); i++) {
 		if (layers[i].kvlist)
diff --git a/lib/librte_eal/include/rte_bus.h b/lib/librte_eal/include/rte_bus.h
index 80b154fb98..e006b514de 100644
--- a/lib/librte_eal/include/rte_bus.h
+++ b/lib/librte_eal/include/rte_bus.h
@@ -210,6 +210,24 @@ typedef int (*rte_bus_hot_unplug_handler_t)(struct rte_device *dev);
  */
 typedef int (*rte_bus_sigbus_handler_t)(const void *failure_addr);
 
+/**
+ * Parse device arguments, setting the device name in the devargs as a result.
+ * A bus could use the class and driver layers to resolve name furthermore.
+ *
+ * On error rte_errno is set.
+ *
+ * @param da
+ *	Pointer to the devargs to parse.
+ *	The 'bus_str' field must be set.
+ *
+ * @return
+ *	0 on successful parsing.
+ *	-EINVAL: on parsing error.
+ *	-ENODEV: if no key matching a device argument is specified.
+ *	-E2BIG: device name is too long.
+ */
+typedef int (*rte_bus_devargs_parse_t)(struct rte_devargs *da);
+
 /**
  * Bus scan policies
  */
@@ -267,6 +285,7 @@ struct rte_bus {
 				/**< handle hot-unplug failure on the bus */
 	rte_bus_sigbus_handler_t sigbus_handler;
 					/**< handle sigbus error on the bus */
+	rte_bus_devargs_parse_t devargs_parse; /**< Parse device arguments */
 
 };
 
-- 
2.25.1