/* Generic interface to network devices. */
-#include <assert.h>
-
#include "netdev.h"
#include "list.h"
#include "shash.h"
/* A network device (e.g. an Ethernet device).
*
- * This structure should be treated as opaque by network device
- * implementations. */
-struct netdev_dev {
+ * Network device implementations may read these members but should not modify
+ * them. */
+struct netdev {
+ /* The following do not change during the lifetime of a struct netdev. */
char *name; /* Name of network device. */
const struct netdev_class *netdev_class; /* Functions to control
this device. */
+
+ /* The following are protected by 'netdev_mutex' (internal to netdev.c). */
+ int n_rxq;
int ref_cnt; /* Times this devices was opened. */
struct shash_node *node; /* Pointer to element in global map. */
+ struct list saved_flags_list; /* Contains "struct netdev_saved_flags". */
};
-void netdev_dev_init(struct netdev_dev *, const char *name,
- const struct netdev_class *);
-void netdev_dev_uninit(struct netdev_dev *, bool destroy);
-const char *netdev_dev_get_type(const struct netdev_dev *);
-const struct netdev_class *netdev_dev_get_class(const struct netdev_dev *);
-const char *netdev_dev_get_name(const struct netdev_dev *);
-struct netdev_dev *netdev_dev_from_name(const char *name);
-void netdev_dev_get_devices(const struct netdev_class *,
- struct shash *device_list);
-
-static inline void netdev_dev_assert_class(const struct netdev_dev *netdev_dev,
- const struct netdev_class *class_)
-{
- assert(netdev_dev->netdev_class == class_);
-}
+const char *netdev_get_type(const struct netdev *);
+const struct netdev_class *netdev_get_class(const struct netdev *);
+const char *netdev_get_name(const struct netdev *);
+struct netdev *netdev_from_name(const char *name);
+void netdev_get_devices(const struct netdev_class *,
+ struct shash *device_list);
-/* A instance of an open network device.
+/* A data structure for capturing packets received by a network device.
*
- * This structure should be treated as opaque by network device
- * implementations. */
-struct netdev {
- struct netdev_dev *netdev_dev; /* Parent netdev_dev. */
- struct list node; /* Element in global list. */
-
- enum netdev_flags save_flags; /* Initial device flags. */
- enum netdev_flags changed_flags; /* Flags that we changed. */
+ * Network device implementations may read these members but should not modify
+ * them.
+ *
+ * None of these members change during the lifetime of a struct netdev_rxq. */
+struct netdev_rxq {
+ struct netdev *netdev; /* Owns a reference to the netdev. */
+ int queue_id;
};
-void netdev_init(struct netdev *, struct netdev_dev *);
-void netdev_uninit(struct netdev *, bool close);
-struct netdev_dev *netdev_get_dev(const struct netdev *);
-
-static inline void netdev_assert_class(const struct netdev *netdev,
- const struct netdev_class *netdev_class)
-{
- netdev_dev_assert_class(netdev_get_dev(netdev), netdev_class);
-}
+struct netdev *netdev_rxq_get_netdev(const struct netdev_rxq *);
/* Network device class structure, to be defined by each implementation of a
* network device.
*
* These functions return 0 if successful or a positive errno value on failure,
- * except where otherwise noted. */
+ * except where otherwise noted.
+ *
+ *
+ * Data Structures
+ * ===============
+ *
+ * These functions work primarily with two different kinds of data structures:
+ *
+ * - "struct netdev", which represents a network device.
+ *
+ * - "struct netdev_rxq", which represents a handle for capturing packets
+ * received on a network device
+ *
+ * Each of these data structures contains all of the implementation-independent
+ * generic state for the respective concept, called the "base" state. None of
+ * them contains any extra space for implementations to use. Instead, each
+ * implementation is expected to declare its own data structure that contains
+ * an instance of the generic data structure plus additional
+ * implementation-specific members, called the "derived" state. The
+ * implementation can use casts or (preferably) the CONTAINER_OF macro to
+ * obtain access to derived state given only a pointer to the embedded generic
+ * data structure.
+ *
+ *
+ * Life Cycle
+ * ==========
+ *
+ * Four stylized functions accompany each of these data structures:
+ *
+ * "alloc" "construct" "destruct" "dealloc"
+ * ------------ ---------------- --------------- --------------
+ * netdev ->alloc ->construct ->destruct ->dealloc
+ * netdev_rxq ->rxq_alloc ->rxq_construct ->rxq_destruct ->rxq_dealloc
+ *
+ * Any instance of a given data structure goes through the following life
+ * cycle:
+ *
+ * 1. The client calls the "alloc" function to obtain raw memory. If "alloc"
+ * fails, skip all the other steps.
+ *
+ * 2. The client initializes all of the data structure's base state. If this
+ * fails, skip to step 7.
+ *
+ * 3. The client calls the "construct" function. The implementation
+ * initializes derived state. It may refer to the already-initialized
+ * base state. If "construct" fails, skip to step 6.
+ *
+ * 4. The data structure is now initialized and in use.
+ *
+ * 5. When the data structure is no longer needed, the client calls the
+ * "destruct" function. The implementation uninitializes derived state.
+ * The base state has not been uninitialized yet, so the implementation
+ * may still refer to it.
+ *
+ * 6. The client uninitializes all of the data structure's base state.
+ *
+ * 7. The client calls the "dealloc" to free the raw memory. The
+ * implementation must not refer to base or derived state in the data
+ * structure, because it has already been uninitialized.
+ *
+ * If netdev support multi-queue IO then netdev->construct should set initialize
+ * netdev->n_rxq to number of queues.
+ *
+ * Each "alloc" function allocates and returns a new instance of the respective
+ * data structure. The "alloc" function is not given any information about the
+ * use of the new data structure, so it cannot perform much initialization.
+ * Its purpose is just to ensure that the new data structure has enough room
+ * for base and derived state. It may return a null pointer if memory is not
+ * available, in which case none of the other functions is called.
+ *
+ * Each "construct" function initializes derived state in its respective data
+ * structure. When "construct" is called, all of the base state has already
+ * been initialized, so the "construct" function may refer to it. The
+ * "construct" function is allowed to fail, in which case the client calls the
+ * "dealloc" function (but not the "destruct" function).
+ *
+ * Each "destruct" function uninitializes and frees derived state in its
+ * respective data structure. When "destruct" is called, the base state has
+ * not yet been uninitialized, so the "destruct" function may refer to it. The
+ * "destruct" function is not allowed to fail.
+ *
+ * Each "dealloc" function frees raw memory that was allocated by the the
+ * "alloc" function. The memory's base and derived members might not have ever
+ * been initialized (but if "construct" returned successfully, then it has been
+ * "destruct"ed already). The "dealloc" function is not allowed to fail.
+ *
+ *
+ * Device Change Notification
+ * ==========================
+ *
+ * Minimally, implementations are required to report changes to netdev flags,
+ * features, ethernet address or carrier through connectivity_seq. Changes to
+ * other properties are allowed to cause notification through this interface,
+ * although implementations should try to avoid this. connectivity_seq_get()
+ * can be used to acquire a reference to the struct seq. The interface is
+ * described in detail in seq.h. */
struct netdev_class {
/* Type of netdevs in this class, e.g. "system", "tap", "gre", etc.
*
* the system. */
const char *type;
+/* ## ------------------- ## */
+/* ## Top-Level Functions ## */
+/* ## ------------------- ## */
+
/* Called when the netdev provider is registered, typically at program
* startup. Returning an error from this function will prevent any network
* device in this class from being opened.
* needed here. */
void (*wait)(void);
- /* 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,
- struct netdev_dev **netdev_devp);
+/* ## ---------------- ## */
+/* ## netdev Functions ## */
+/* ## ---------------- ## */
- /* Destroys 'netdev_dev'.
- *
- * Netdev devices maintain a reference count that is incremented on
- * netdev_open() and decremented on netdev_close(). If 'netdev_dev'
- * has a non-zero reference count, then this function will not be
- * called. */
- void (*destroy)(struct netdev_dev *netdev_dev);
+ /* Life-cycle functions for a netdev. See the large comment above on
+ * struct netdev_class. */
+ struct netdev *(*alloc)(void);
+ int (*construct)(struct netdev *);
+ void (*destruct)(struct netdev *);
+ void (*dealloc)(struct netdev *);
- /* Fetches the device 'netdev_dev''s configuration, storing it in 'args'.
+ /* Fetches the device 'netdev''s configuration, storing it in 'args'.
* The caller owns 'args' and pre-initializes it to an empty smap.
*
* 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 smap *args);
+ int (*get_config)(const struct netdev *netdev, struct smap *args);
- /* Changes the device 'netdev_dev''s configuration to 'args'.
+ /* Changes the device 'netdev''s configuration to 'args'.
*
* If this netdev class does not support configuration, this may be a null
* pointer. */
- int (*set_config)(struct netdev_dev *netdev_dev, const struct smap *args);
+ int (*set_config)(struct netdev *netdev, const struct smap *args);
- /* Returns the tunnel configuration of 'netdev_dev'. If 'netdev_dev' is
+ /* Returns the tunnel configuration of 'netdev'. If 'netdev' is
* not a tunnel, returns null.
*
* If this function would always return null, it may be null instead. */
const struct netdev_tunnel_config *
- (*get_tunnel_config)(const struct netdev_dev *netdev_dev);
-
- /* Attempts to open a network device. On success, sets '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.) */
-
- /* 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);
+ (*get_tunnel_config)(const 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.
+ /* Sends the 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 if a partial packet was transmitted or if the packet
+ * is too big or too small to transmit on the device.
*
- * Returns -EMSGSIZE, and discards the packet, if the received packet is
- * longer than 'size' bytes.
- *
- * 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
- * poll_block() when a packet is ready to be received with netdev_recv() on
- * 'netdev'.
- *
- * May be null if not needed, such as for a network device that does not
- * implement packet reception through the 'recv' member function. */
- void (*recv_wait)(struct netdev *netdev);
-
- /* Discards all packets waiting to be received from 'netdev'.
- *
- * 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
- * if a partial packet was transmitted or if the packet is too big or too
- * small to transmit on the device.
- *
- * The caller retains ownership of 'buffer' in all cases.
+ * To retain ownership of 'buffer' caller can set may_steal to false.
*
* The network device is expected to maintain a packet transmission queue,
* so that the caller does not ordinarily have to do additional queuing of
* network device from being usefully used by the netdev-based "userspace
* datapath". It will also prevent the OVS implementation of bonding from
* working properly over 'netdev'.) */
- int (*send)(struct netdev *netdev, const void *buffer, size_t size);
+ int (*send)(struct netdev *netdev, struct ofpbuf *buffer, bool may_steal);
/* Registers with the poll loop to wake up from the next call to
* poll_block() when the packet transmission queue for 'netdev' has
int (*get_queue_stats)(const struct netdev *netdev, unsigned int queue_id,
struct netdev_queue_stats *stats);
- /* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
- * ID, its configuration, and the 'aux' specified by the caller. The order
- * of iteration is unspecified, but (when successful) each queue is visited
- * exactly once.
- *
- * 'cb' will not modify or free the 'details' argument passed in. It may
- * delete or modify the queue passed in as its 'queue_id' argument. It may
- * modify but will not delete any other queue within 'netdev'. If 'cb'
- * adds new queues, then ->dump_queues is allowed to visit some queues
- * twice or not at all.
- */
- int (*dump_queues)(const struct netdev *netdev,
- void (*cb)(unsigned int queue_id,
- const struct smap *details,
- void *aux),
- void *aux);
+ /* Attempts to begin dumping the queues in 'netdev'. On success, returns 0
+ * and initializes '*statep' with any data needed for iteration. On
+ * failure, returns a positive errno value.
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_start)(const struct netdev *netdev, void **statep);
+
+ /* Attempts to retrieve another queue from 'netdev' for 'state', which was
+ * initialized by a successful call to the 'queue_dump_start' function for
+ * 'netdev'. On success, stores a queue ID into '*queue_id' and fills
+ * 'details' with the configuration of the queue with that ID. Returns EOF
+ * if the last queue has been dumped, or a positive errno value on error.
+ * This function will not be called again once it returns nonzero once for
+ * a given iteration (but the 'queue_dump_done' function will be called
+ * afterward).
+ *
+ * The caller initializes and clears 'details' before calling this
+ * function. The caller takes ownership of the string key-values pairs
+ * added to 'details'.
+ *
+ * The returned contents of 'details' should be documented as valid for the
+ * given 'type' in the "other_config" column in the "Queue" table in
+ * vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)).
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_next)(const struct netdev *netdev, void *state,
+ unsigned int *queue_id, struct smap *details);
+
+ /* Releases resources from 'netdev' for 'state', which was initialized by a
+ * successful call to the 'queue_dump_start' function for 'netdev'.
+ *
+ * May be NULL if 'netdev' does not support QoS at all. */
+ int (*queue_dump_done)(const struct netdev *netdev, void *state);
/* Iterates over all of 'netdev''s queues, calling 'cb' with the queue's
* ID, its statistics, and the 'aux' specified by the caller. The order of
* anyhow. */
int (*add_router)(struct netdev *netdev, struct in_addr router);
- /* Looks up the next hop for 'host'. If succesful, stores the next hop
+ /* Looks up the next hop for 'host'. If successful, stores the next hop
* gateway's address (0 if 'host' is on a directly connected network) in
* '*next_hop' and a copy of the name of the device to reach 'host' in
* '*netdev_name', and returns 0. The caller is responsible for freeing
int (*arp_lookup)(const struct netdev *netdev, ovs_be32 ip,
uint8_t mac[6]);
- /* Retrieves the current set of flags on 'netdev' into '*old_flags'.
- * Then, turns off the flags that are set to 1 in 'off' and turns on the
- * flags that are set to 1 in 'on'. (No bit will be set to 1 in both 'off'
- * and 'on'; that is, off & on == 0.)
+ /* Retrieves the current set of flags on 'netdev' into '*old_flags'. Then,
+ * turns off the flags that are set to 1 in 'off' and turns on the flags
+ * that are set to 1 in 'on'. (No bit will be set to 1 in both 'off' and
+ * 'on'; that is, off & on == 0.)
*
* This function may be invoked from a signal handler. Therefore, it
* should not do anything that is not signal-safe (such as logging). */
int (*update_flags)(struct netdev *netdev, enum netdev_flags off,
enum netdev_flags on, enum netdev_flags *old_flags);
- /* 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'.
+/* ## -------------------- ## */
+/* ## netdev_rxq Functions ## */
+/* ## -------------------- ## */
+
+/* If a particular netdev class does not support receiving packets, all these
+ * function pointers must be NULL. */
+
+ /* Life-cycle functions for a netdev_rxq. See the large comment above on
+ * struct netdev_class. */
+ struct netdev_rxq *(*rxq_alloc)(void);
+ int (*rxq_construct)(struct netdev_rxq *);
+ void (*rxq_destruct)(struct netdev_rxq *);
+ void (*rxq_dealloc)(struct netdev_rxq *);
+
+ /* Attempts to receive batch of packets from 'rx' and place array of pointers
+ * into '*pkt'. netdev is responsible for allocating buffers.
+ * '*cnt' points to packet count for given batch. Once packets are returned
+ * to caller, netdev should give up ownership of ofpbuf data.
+ *
+ * Implementations should allocate buffer with DP_NETDEV_HEADROOM headroom
+ * and add a VLAN header which is obtained out-of-band to the packet.
*
- * 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);
+ * Caller is expected to pass array of size MAX_RX_BATCH.
+ * This function may be set to null if it would always return EOPNOTSUPP
+ * anyhow. */
+ int (*rxq_recv)(struct netdev_rxq *rx, struct ofpbuf **pkt, int *cnt);
+
+ /* Registers with the poll loop to wake up from the next call to
+ * poll_block() when a packet is ready to be received with netdev_rxq_recv()
+ * on 'rx'. */
+ void (*rxq_wait)(struct netdev_rxq *rx);
+
+ /* Discards all packets waiting to be received from 'rx'. */
+ int (*rxq_drain)(struct netdev_rxq *rx);
};
int netdev_register_provider(const struct netdev_class *);
int netdev_unregister_provider(const char *type);
-const struct netdev_class *netdev_lookup_provider(const char *type);
extern const struct netdev_class netdev_linux_class;
extern const struct netdev_class netdev_internal_class;
extern const struct netdev_class netdev_tap_class;
-#ifdef __FreeBSD__
+#if defined(__FreeBSD__) || defined(__NetBSD__)
extern const struct netdev_class netdev_bsd_class;
#endif
+extern const struct netdev_class netdev_tunnel_class;
+extern const struct netdev_class netdev_pltap_class;
+
#ifdef __cplusplus
}
#endif