- /* Releases resources from 'dpif' for 'state', which was initialized by a
- * successful call to the 'flow_dump_start' function for 'dpif'. */
- int (*flow_dump_done)(const struct dpif *dpif, void *state);
-
- /* Performs the 'actions_len' bytes of actions in 'actions' on the Ethernet
- * frame specified in 'packet'. */
- int (*execute)(struct dpif *dpif, const struct nlattr *actions,
- size_t actions_len, const struct ofpbuf *packet);
-
- /* Retrieves 'dpif''s "listen mask" into '*listen_mask'. A 1-bit of value
- * 2**X set in '*listen_mask' indicates that 'dpif' will receive messages
- * of the type (from "enum dpif_upcall_type") with value X when its 'recv'
- * function is called. */
- int (*recv_get_mask)(const struct dpif *dpif, int *listen_mask);
-
- /* Sets 'dpif''s "listen mask" to 'listen_mask'. A 1-bit of value 2**X set
- * in '*listen_mask' requests that 'dpif' will receive messages of the type
- * (from "enum dpif_upcall_type") with value X when its 'recv' function is
- * called. */
- int (*recv_set_mask)(struct dpif *dpif, int listen_mask);
-
- /* Retrieves 'dpif''s sFlow sampling probability into '*probability'.
- * Return value is 0 or a positive errno value. EOPNOTSUPP indicates that
- * the datapath does not support sFlow, as does a null pointer.
- *
- * '*probability' is expressed as the number of packets out of UINT_MAX to
- * sample, e.g. probability/UINT_MAX is the probability of sampling a given
- * packet. */
- int (*get_sflow_probability)(const struct dpif *dpif,
- uint32_t *probability);
-
- /* Sets 'dpif''s sFlow sampling probability to 'probability'. Return value
- * is 0 or a positive errno value. EOPNOTSUPP indicates that the datapath
- * does not support sFlow, as does a null pointer.
- *
- * 'probability' is expressed as the number of packets out of UINT_MAX to
- * sample, e.g. probability/UINT_MAX is the probability of sampling a given
- * packet. */
- int (*set_sflow_probability)(struct dpif *dpif, uint32_t probability);
+ /* Determines whether the next call to 'flow_dump_next' with 'state' will
+ * modify or free the keys that it previously returned. 'state' must have
+ * been initialized by a call to 'flow_dump_state_init' for 'dpif'.
+ *
+ * 'dpif' guarantees that data returned by flow_dump_next() will remain
+ * accessible and unchanging until the next call. This function provides a
+ * way for callers to determine whether that guarantee extends beyond the
+ * next call.
+ *
+ * Returns true if the next call to flow_dump_next() is expected to be
+ * destructive to previously returned keys for 'state', false otherwise. */
+ bool (*flow_dump_next_may_destroy_keys)(void *state);
+
+ /* Releases resources from 'dpif' for 'iter', which was initialized by a
+ * successful call to the 'flow_dump_start' function for 'dpif'. Callers
+ * must ensure that this function is called once within a given iteration,
+ * as the final flow dump operation. */
+ int (*flow_dump_done)(const struct dpif *dpif, void *iter);
+
+ /* Releases 'state' which was initialized by a call to the
+ * 'flow_dump_state_init' function for this 'dpif'. */
+ void (*flow_dump_state_uninit)(void *statep);
+
+ /* Performs the 'execute->actions_len' bytes of actions in
+ * 'execute->actions' on the Ethernet frame in 'execute->packet'
+ * and on the packet metadata in 'execute->md'.
+ * May modify both packet and metadata. */
+ int (*execute)(struct dpif *dpif, struct dpif_execute *execute);
+
+ /* Executes each of the 'n_ops' operations in 'ops' on 'dpif', in the order
+ * in which they are specified, placing each operation's results in the
+ * "output" members documented in comments.
+ *
+ * This function is optional. It is only worthwhile to implement it if
+ * 'dpif' can perform operations in batch faster than individually. */
+ void (*operate)(struct dpif *dpif, struct dpif_op **ops, size_t n_ops);
+
+ /* Enables or disables receiving packets with dpif_recv() for 'dpif'.
+ * Turning packet receive off and then back on is allowed to change Netlink
+ * PID assignments (see ->port_get_pid()). The client is responsible for
+ * updating flows as necessary if it does this. */
+ int (*recv_set)(struct dpif *dpif, bool enable);
+
+ /* Refreshes the poll loops and Netlink sockets associated to each port,
+ * when the number of upcall handlers (upcall receiving thread) is changed
+ * to 'n_handlers' and receiving packets for 'dpif' is enabled by
+ * recv_set().
+ *
+ * Since multiple upcall handlers can read upcalls simultaneously from
+ * 'dpif', each port can have multiple Netlink sockets, one per upcall
+ * handler. So, handlers_set() is responsible for the following tasks:
+ *
+ * When receiving upcall is enabled, extends or creates the
+ * configuration to support:
+ *
+ * - 'n_handlers' Netlink sockets for each port.
+ *
+ * - 'n_handlers' poll loops, one for each upcall handler.
+ *
+ * - registering the Netlink sockets for the same upcall handler to
+ * the corresponding poll loop.
+ * */
+ int (*handlers_set)(struct dpif *dpif, uint32_t n_handlers);