dev: introduce driver accessors

Prepare for making the driver object opaque by adding accessors.
Update existing "external" users.
Internal users may still dereference a rte_driver object.

Signed-off-by: David Marchand <david.marchand@redhat.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>

app/test-pmd/config.c

@@ -656,7 +656,7 @@ device_infos_display(const char *identifier)
 			printf("\n%s Infos for device %s %s\n",
 			       info_border, dev->name, info_border);
 			printf("Bus name: %s", rte_bus_name(dev->bus));
-			printf("\nDriver name: %s", dev->driver->name);
+			printf("\nDriver name: %s", rte_driver_name(dev->driver));
 			printf("\nDevargs: %s",
 			       dev->devargs ? dev->devargs->args : "");
 			printf("\nConnect to socket: %d", dev->numa_node);

lib/eal/common/eal_common_dev.c

@@ -20,6 +20,12 @@
 #include "eal_private.h"
 #include "hotplug_mp.h"
 
+const char *
+rte_driver_name(const struct rte_driver *driver)
+{
+	return driver->name;
+}
+
 /**
  * The device event callback description.
  *

lib/eal/include/rte_dev.h

@@ -76,6 +76,21 @@ struct rte_driver {
 	const char *alias;              /**< Driver alias. */
 };
 
+/**
+ * Retrieve a driver name.
+ *
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * @param driver
+ *   A pointer to a driver structure.
+ * @return
+ *   A pointer to the driver name string.
+ */
+__rte_experimental
+const char *
+rte_driver_name(const struct rte_driver *driver);
+
 /*
  * Internal identifier length
  * Sufficiently large to allow for UUID or PCI address

lib/eal/version.map

@@ -424,6 +424,9 @@ EXPERIMENTAL {
 	rte_thread_self;
 	rte_thread_set_affinity_by_id;
 	rte_thread_set_priority;
+
+	# added in 22.11
+	rte_driver_name;
 };
 
 INTERNAL {

lib/ethdev/rte_ethdev.h

@@ -3380,7 +3380,7 @@ int rte_eth_macaddrs_get(uint16_t port_id, struct rte_ether_addr *ma,
  * exists for the device and the rte_eth_dev 'dev' has been populated
  * successfully with a call to it:
  *
- * driver_name = dev->device->driver->name
+ * driver_name = rte_driver_name(dev->device->driver)
  * nb_rx_queues = dev->data->nb_rx_queues
  * nb_tx_queues = dev->data->nb_tx_queues
  * dev_flags = &dev->data->dev_flags