this device. */
int ref_cnt; /* Times this devices was opened. */
struct shash_node *node; /* Pointer to element in global map. */
- struct shash args; /* Argument list from last config. */
};
void netdev_dev_init(struct netdev_dev *, const char *name,
- const struct shash *args,
const struct netdev_class *);
void netdev_dev_uninit(struct netdev_dev *, bool destroy);
const char *netdev_dev_get_type(const struct netdev_dev *);
netdev_dev_assert_class(netdev_get_dev(netdev), netdev_class);
}
-/* A network device notifier.
- *
- * Network device implementations should use netdev_notifier_init() to
- * initialize this structure, but they may freely read its members after
- * initialization. */
-struct netdev_notifier {
- struct netdev *netdev;
- void (*cb)(struct netdev_notifier *);
- void *aux;
-};
-void netdev_notifier_init(struct netdev_notifier *, struct netdev *,
- void (*cb)(struct netdev_notifier *), void *aux);
-
/* Network device class structure, to be defined by each implementation of a
* network device.
*
void (*run)(void);
/* Arranges for poll_block() to wake up if the "run" member function needs
- * to be called. May be null if nothing is needed here. */
+ * to be called. Implementations are additionally required to wake
+ * whenever something changes in any of its netdevs which would cause their
+ * ->change_seq() function to change its result. May be null if nothing is
+ * needed here. */
void (*wait)(void);
- /* Attempts to create a network device named 'name' with initial 'args' in
- * 'netdev_class'. On success sets 'netdev_devp' to the newly created
- * device. */
+ /* Attempts to create a network device named 'name' in 'netdev_class'. On
+ * success sets 'netdev_devp' to the newly created device. */
int (*create)(const struct netdev_class *netdev_class, const char *name,
- const struct shash *args, struct netdev_dev **netdev_devp);
+ struct netdev_dev **netdev_devp);
/* Destroys 'netdev_dev'.
*
* called. */
void (*destroy)(struct netdev_dev *netdev_dev);
+ /* Fetches the device 'netdev_dev''s configuration, storing it in 'args'.
+ * The caller owns 'args' and pre-initializes it to an empty shash.
+ *
+ * If this netdev class does not have any configuration options, this may
+ * be a null pointer. */
+ int (*get_config)(struct netdev_dev *netdev_dev, struct shash *args);
+
/* Changes the device 'netdev_dev''s configuration to 'args'.
*
- * If this netdev class does not support reconfiguring a netdev
- * device, this may be a null pointer.
- */
+ * If this netdev class does not support configuration, this may be a null
+ * pointer. */
int (*set_config)(struct netdev_dev *netdev_dev, const struct shash *args);
/* Attempts to open a network device. On success, sets 'netdevp'
- * to the new network device.
- *
- * 'ethertype' may be a 16-bit Ethernet protocol value in host byte order
- * to capture frames of that type received on the device. It may also be
- * one of the 'enum netdev_pseudo_ethertype' values to receive frames in
- * one of those categories. */
- int (*open)(struct netdev_dev *netdev_dev, int ethertype,
- struct netdev **netdevp);
+ * to the new network device. */
+ int (*open)(struct netdev_dev *netdev_dev, struct netdev **netdevp);
/* Closes 'netdev'. */
void (*close)(struct netdev *netdev);
+\f
+/* ## ----------------- ## */
+/* ## Receiving Packets ## */
+/* ## ----------------- ## */
+
+/* The network provider interface is mostly used for inspecting and configuring
+ * device "metadata", not for sending and receiving packets directly. It may
+ * be impractical to implement these functions on some operating systems and
+ * hardware. These functions may all be NULL in such cases.
+ *
+ * (However, the "dpif-netdev" implementation, which is the easiest way to
+ * integrate Open vSwitch with a new operating system or hardware, does require
+ * the ability to receive packets.) */
- /* Enumerates the names of all network devices of this class.
- *
- * The caller has already initialized 'all_names' and might already have
- * added some names to it. This function should not disturb any existing
- * names in 'all_names'.
- *
- * If this netdev class does not support enumeration, this may be a null
- * pointer. */
- int (*enumerate)(struct sset *all_names);
+ /* Attempts to set up 'netdev' for receiving packets with ->recv().
+ * Returns 0 if successful, otherwise a positive errno value. Return
+ * EOPNOTSUPP to indicate that the network device does not implement packet
+ * reception through this interface. This function may be set to null if
+ * it would always return EOPNOTSUPP anyhow. (This will prevent the
+ * network device from being usefully used by the netdev-based "userspace
+ * datapath".)*/
+ int (*listen)(struct netdev *netdev);
/* Attempts to receive a packet from 'netdev' into the 'size' bytes in
* 'buffer'. If successful, returns the number of bytes in the received
* packet, otherwise a negative errno value. Returns -EAGAIN immediately
* if no packet is ready to be received.
*
- * May return -EOPNOTSUPP if a network device does not implement packet
- * reception through this interface. This function may be set to null if
- * it would always return -EOPNOTSUPP anyhow. (This will prevent the
- * network device from being usefully used by the netdev-based "userspace
- * datapath".) */
+ * This function can only be expected to return a packet if ->listen() has
+ * been called successfully.
+ *
+ * May be null if not needed, such as for a network device that does not
+ * implement packet reception through the 'recv' member function. */
int (*recv)(struct netdev *netdev, void *buffer, size_t size);
/* Registers with the poll loop to wake up from the next call to
* May be null if not needed, such as for a network device that does not
* implement packet reception through the 'recv' member function. */
int (*drain)(struct netdev *netdev);
-
+\f
/* Sends the 'size'-byte packet in 'buffer' on 'netdev'. Returns 0 if
* successful, otherwise a positive errno value. Returns EAGAIN without
* blocking if the packet cannot be queued immediately. Returns EMSGSIZE
* bytes for Ethernet devices.
*
* If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
- * this function should set '*mtup' to INT_MAX. */
+ * this function should return EOPNOTSUPP. This function may be set to
+ * null if it would always return EOPNOTSUPP. */
int (*get_mtu)(const struct netdev *netdev, int *mtup);
+ /* Sets 'netdev''s MTU to 'mtu'.
+ *
+ * If 'netdev' does not have an MTU (e.g. as some tunnels do not), then
+ * this function should return EOPNOTSUPP. This function may be set to
+ * null if it would always return EOPNOTSUPP. */
+ int (*set_mtu)(const struct netdev *netdev, int mtu);
+
/* Returns the ifindex of 'netdev', if successful, as a positive number.
* On failure, returns a negative errno value.
*
*/
int (*get_carrier)(const struct netdev *netdev, bool *carrier);
- /* Sets 'miimon' to true if 'netdev' is up according to its MII. If
- * 'netdev' does not support MII, may fall back to another method or return
- * EOPNOTSUPP.
+ /* Forces ->get_carrier() to poll 'netdev''s MII registers for link status
+ * instead of checking 'netdev''s carrier. 'netdev''s MII registers will
+ * be polled once ever 'interval' milliseconds. If 'netdev' does not
+ * support MII, another method may be used as a fallback. If 'interval' is
+ * less than or equal to zero, reverts ->get_carrier() to its normal
+ * behavior.
*
- * This function may be set to null if it would always return EOPNOTSUPP.
+ * Most network devices won't support this feature and will set this
+ * function pointer to NULL, which is equivalent to returning EOPNOTSUPP.
*/
- int (*get_miimon)(const struct netdev *netdev, bool *miimon);
+ int (*set_miimon_interval)(struct netdev *netdev, long long int interval);
/* Retrieves current device stats for 'netdev' into 'stats'.
*
int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
enum netdev_flags on, enum netdev_flags *old_flags);
- /* Arranges for 'cb' to be called whenever one of the attributes of
- * 'netdev' changes and sets '*notifierp' to a newly created
- * netdev_notifier that represents this arrangement. The created notifier
- * will have its 'netdev', 'cb', and 'aux' members set to the values of the
- * corresponding parameters. */
- int (*poll_add)(struct netdev *netdev,
- void (*cb)(struct netdev_notifier *notifier), void *aux,
- struct netdev_notifier **notifierp);
-
- /* Cancels poll notification for 'notifier'. */
- void (*poll_remove)(struct netdev_notifier *notifier);
+ /* Returns a sequence number which indicates changes in one of 'netdev''s
+ * properties. The returned sequence number must be nonzero so that
+ * callers have a value which they may use as a reset when tracking
+ * 'netdev'.
+ *
+ * Minimally, the returned sequence number is required to change whenever
+ * 'netdev''s flags, features, ethernet address, or carrier changes. The
+ * returned sequence number is allowed to change even when 'netdev' doesn't
+ * change, although implementations should try to avoid this. */
+ unsigned int (*change_seq)(const struct netdev *netdev);
};
int netdev_register_provider(const struct netdev_class *);