ethdev: add switch domain allocator

Add switch domain allocate and free API to enable NET devices to
synchronise switch domain allocation.

Signed-off-by: Declan Doherty <declan.doherty@intel.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

lib/librte_ether/rte_ethdev.c

@@ -4126,6 +4126,60 @@ rte_eth_dev_pool_ops_supported(uint16_t port_id, const char *pool)
 	return (*dev->dev_ops->pool_ops_supported)(dev, pool);
 }
 
+/**
+ * A set of values to describe the possible states of a switch domain.
+ */
+enum rte_eth_switch_domain_state {
+	RTE_ETH_SWITCH_DOMAIN_UNUSED = 0,
+	RTE_ETH_SWITCH_DOMAIN_ALLOCATED
+};
+
+/**
+ * Array of switch domains available for allocation. Array is sized to
+ * RTE_MAX_ETHPORTS elements as there cannot be more active switch domains than
+ * ethdev ports in a single process.
+ */
+struct rte_eth_dev_switch {
+	enum rte_eth_switch_domain_state state;
+} rte_eth_switch_domains[RTE_MAX_ETHPORTS];
+
+int __rte_experimental
+rte_eth_switch_domain_alloc(uint16_t *domain_id)
+{
+	unsigned int i;
+
+	*domain_id = RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID;
+
+	for (i = RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID + 1;
+		i < RTE_MAX_ETHPORTS; i++) {
+		if (rte_eth_switch_domains[i].state ==
+			RTE_ETH_SWITCH_DOMAIN_UNUSED) {
+			rte_eth_switch_domains[i].state =
+				RTE_ETH_SWITCH_DOMAIN_ALLOCATED;
+			*domain_id = i;
+			return 0;
+		}
+	}
+
+	return -ENOSPC;
+}
+
+int __rte_experimental
+rte_eth_switch_domain_free(uint16_t domain_id)
+{
+	if (domain_id == RTE_ETH_DEV_SWITCH_DOMAIN_ID_INVALID ||
+		domain_id >= RTE_MAX_ETHPORTS)
+		return -EINVAL;
+
+	if (rte_eth_switch_domains[domain_id].state !=
+		RTE_ETH_SWITCH_DOMAIN_ALLOCATED)
+		return -EINVAL;
+
+	rte_eth_switch_domains[domain_id].state = RTE_ETH_SWITCH_DOMAIN_UNUSED;
+
+	return 0;
+}
+
 typedef int (*rte_eth_devargs_callback_t)(char *str, void *data);
 
 static int

lib/librte_ether/rte_ethdev_driver.h

@@ -188,6 +188,43 @@ rte_eth_linkstatus_get(const struct rte_eth_dev *dev,
 #endif
 }
 
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Allocate an unique switch domain identifier.
+ *
+ * A pool of switch domain identifiers which can be allocated on request. This
+ * will enabled devices which support the concept of switch domains to request
+ * a switch domain id which is guaranteed to be unique from other devices
+ * running in the same process.
+ *
+ * @param domain_id
+ *  switch domain identifier parameter to pass back to application
+ *
+ * @return
+ *   Negative errno value on error, 0 on success.
+ */
+int __rte_experimental
+rte_eth_switch_domain_alloc(uint16_t *domain_id);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice.
+ *
+ * Free switch domain.
+ *
+ * Return a switch domain identifier to the pool of free identifiers after it is
+ * no longer in use by device.
+ *
+ * @param domain_id
+ *  switch domain identifier to free
+ *
+ * @return
+ *   Negative errno value on error, 0 on success.
+ */
+int __rte_experimental
+rte_eth_switch_domain_free(uint16_t domain_id);
 
 /** Generic Ethernet device arguments  */
 struct rte_eth_devargs {

lib/librte_ether/rte_ethdev_version.map

@@ -228,6 +228,8 @@ EXPERIMENTAL {
 	rte_eth_dev_owner_unset;
 	rte_eth_dev_rx_offload_name;
 	rte_eth_dev_tx_offload_name;
+	rte_eth_switch_domain_alloc;
+	rte_eth_switch_domain_free;
 	rte_mtr_capabilities_get;
 	rte_mtr_create;
 	rte_mtr_destroy;