+/**
+ * Device comparison function.
+ *
+ * This type of function is used to compare an rte_device with arbitrary
+ * data.
+ *
+ * @param dev
+ * Device handle.
+ *
+ * @param data
+ * Data to compare against. The type of this parameter is determined by
+ * the kind of comparison performed by the function.
+ *
+ * @return
+ * 0 if the device matches the data.
+ * !0 if the device does not match.
+ * <0 if ordering is possible and the device is lower than the data.
+ * >0 if ordering is possible and the device is greater than the data.
+ */
+typedef int (*rte_dev_cmp_t)(const struct rte_device *dev, const void *data);
+
+#define RTE_PMD_EXPORT_NAME_ARRAY(n, idx) n##idx[]
+
+#define RTE_PMD_EXPORT_NAME(name, idx) \
+static const char RTE_PMD_EXPORT_NAME_ARRAY(this_pmd_name, idx) \
+__attribute__((used)) = RTE_STR(name)
+
+#define DRV_EXP_TAG(name, tag) __##name##_##tag
+
+#define RTE_PMD_REGISTER_PCI_TABLE(name, table) \
+static const char DRV_EXP_TAG(name, pci_tbl_export)[] __attribute__((used)) = \
+RTE_STR(table)
+
+#define RTE_PMD_REGISTER_PARAM_STRING(name, str) \
+static const char DRV_EXP_TAG(name, param_string_export)[] \
+__attribute__((used)) = str
+
+/**
+ * Advertise the list of kernel modules required to run this driver
+ *
+ * This string lists the kernel modules required for the devices
+ * associated to a PMD. The format of each line of the string is:
+ * "<device-pattern> <kmod-expression>".
+ *
+ * The possible formats for the device pattern are:
+ * "*" all devices supported by this driver
+ * "pci:*" all PCI devices supported by this driver
+ * "pci:v8086:d*:sv*:sd*" all PCI devices supported by this driver
+ * whose vendor id is 0x8086.
+ *
+ * The format of the kernel modules list is a parenthesized expression
+ * containing logical-and (&) and logical-or (|).
+ *
+ * The device pattern and the kmod expression are separated by a space.
+ *
+ * Example:
+ * - "* igb_uio | uio_pci_generic | vfio"
+ */
+#define RTE_PMD_REGISTER_KMOD_DEP(name, str) \
+static const char DRV_EXP_TAG(name, kmod_dep_export)[] \
+__attribute__((used)) = str
+
+/**
+ * Iteration context.
+ *
+ * This context carries over the current iteration state.
+ */
+struct rte_dev_iterator {
+ const char *dev_str; /**< device string. */
+ const char *bus_str; /**< bus-related part of device string. */
+ const char *cls_str; /**< class-related part of device string. */
+ struct rte_bus *bus; /**< bus handle. */
+ struct rte_class *cls; /**< class handle. */
+ struct rte_device *device; /**< current position. */
+ void *class_device; /**< additional specialized context. */
+};
+
+/**
+ * Device iteration function.
+ *
+ * Find the next device matching properties passed in parameters.
+ * The function takes an additional ``start`` parameter, that is
+ * used as starting context when relevant.
+ *
+ * The function returns the current element in the iteration.
+ * This return value will potentially be used as a start parameter
+ * in subsequent calls to the function.
+ *
+ * The additional iterator parameter is only there if a specific
+ * implementation needs additional context. It must not be modified by
+ * the iteration function itself.
+ *
+ * @param start
+ * Starting iteration context.
+ *
+ * @param devstr
+ * Device description string.
+ *
+ * @param it
+ * Device iterator.
+ *
+ * @return
+ * The address of the current element matching the device description
+ * string.
+ */
+typedef void *(*rte_dev_iterate_t)(const void *start,
+ const char *devstr,
+ const struct rte_dev_iterator *it);
+
+/**
+ * Initializes a device iterator.
+ *
+ * This iterator allows accessing a list of devices matching a criteria.
+ * The device matching is made among all buses and classes currently registered,
+ * filtered by the device description given as parameter.
+ *
+ * This function will not allocate any memory. It is safe to stop the
+ * iteration at any moment and let the iterator go out of context.
+ *
+ * @param it
+ * Device iterator handle.
+ *
+ * @param str
+ * Device description string.
+ *
+ * @return
+ * 0 on successful initialization.
+ * <0 on error.
+ */
+__rte_experimental
+int
+rte_dev_iterator_init(struct rte_dev_iterator *it, const char *str);
+
+/**
+ * Iterates on a device iterator.
+ *
+ * Generates a new rte_device handle corresponding to the next element
+ * in the list described in comprehension by the iterator.
+ *
+ * The next object is returned, and the iterator is updated.
+ *
+ * @param it
+ * Device iterator handle.
+ *
+ * @return
+ * An rte_device handle if found.
+ * NULL if an error occurred (rte_errno is set).
+ * NULL if no device could be found (rte_errno is not set).
+ */
+__rte_experimental
+struct rte_device *
+rte_dev_iterator_next(struct rte_dev_iterator *it);
+
+#define RTE_DEV_FOREACH(dev, devstr, it) \
+ for (rte_dev_iterator_init(it, devstr), \
+ dev = rte_dev_iterator_next(it); \
+ dev != NULL; \
+ dev = rte_dev_iterator_next(it))