[v11,09/25] eal/dev: add device iterator interface
Checks
Commit Message
A device iterator allows iterating over a set of devices.
This set is defined by the two descriptions offered,
* rte_bus
* rte_class
Only one description can be provided, or both. It is not allowed to
provide no description at all.
Each layer of abstraction then performs a filter based on the
description provided. This filtering allows iterating on their internal
set of devices, stopping when a match is valid and returning the current
iteration context.
This context allows starting the next iteration from the same point and
going forward.
Signed-off-by: Gaetan Rivet <gaetan.rivet@6wind.com>
---
lib/librte_eal/common/include/rte_bus.h | 1 +
lib/librte_eal/common/include/rte_class.h | 1 +
lib/librte_eal/common/include/rte_dev.h | 47 +++++++++++++++++++++++
3 files changed, 49 insertions(+)
@@ -211,6 +211,7 @@ struct rte_bus {
rte_bus_parse_t parse; /**< Parse a device name */
struct rte_bus_conf conf; /**< Bus configuration */
rte_bus_get_iommu_class_t get_iommu_class; /**< Get iommu class */
+ rte_dev_iterate_t dev_iterate; /**< Device iterator. */
};
/**
@@ -35,6 +35,7 @@ TAILQ_HEAD(rte_class_list, rte_class);
struct rte_class {
TAILQ_ENTRY(rte_class) next; /**< Next device class in linked list */
const char *name; /**< Name of the class */
+ rte_dev_iterate_t dev_iterate; /**< Device iterator. */
};
/**
@@ -284,6 +284,53 @@ __attribute__((used)) = 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);
+
#ifdef __cplusplus
}
#endif