/* * Copyright (c) 2009, 2010, 2011, 2012 Nicira, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #ifndef NETDEV_PROVIDER_H #define NETDEV_PROVIDER_H 1 /* Generic interface to network devices. */ #include #include "netdev.h" #include "list.h" #include "shash.h" #include "smap.h" #ifdef __cplusplus extern "C" { #endif /* A network device (e.g. an Ethernet device). * * This structure should be treated as opaque by network device * implementations. */ struct netdev_dev { char *name; /* Name of network device. */ const struct netdev_class *netdev_class; /* Functions to control this device. */ int ref_cnt; /* Times this devices was opened. */ struct shash_node *node; /* Pointer to element in global map. */ }; 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_); } /* A instance of an open 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. */ }; 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); } /* 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. */ struct netdev_class { /* Type of netdevs in this class, e.g. "system", "tap", "gre", etc. * * One of the providers should supply a "system" type, since this is * the type assumed if no type is specified when opening a netdev. * The "system" type corresponds to an existing network device on * the system. */ const char *type; /* 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. * * This function may be set to null if a network device class needs no * initialization at registration time. */ int (*init)(void); /* Performs periodic work needed by netdevs of this class. May be null if * no periodic work is necessary. */ void (*run)(void); /* Arranges for poll_block() to wake up if the "run" member function needs * 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' 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); /* 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); /* Fetches the device 'netdev_dev''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); /* Changes the device 'netdev_dev''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); /* 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); /* ## ----------------- ## */ /* ## 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); /* 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. * * 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); /* 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. * * The network device is expected to maintain a packet transmission queue, * so that the caller does not ordinarily have to do additional queuing of * packets. * * May return EOPNOTSUPP if a network device does not implement packet * transmission 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". 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); /* Registers with the poll loop to wake up from the next call to * poll_block() when the packet transmission queue for 'netdev' has * sufficient room to transmit a packet with netdev_send(). * * The network device is expected to maintain a packet transmission queue, * so that the caller does not ordinarily have to do additional queuing of * packets. Thus, this function is unlikely to ever be useful. * * May be null if not needed, such as for a network device that does not * implement packet transmission through the 'send' member function. */ void (*send_wait)(struct netdev *netdev); /* Sets 'netdev''s Ethernet address to 'mac' */ int (*set_etheraddr)(struct netdev *netdev, const uint8_t mac[6]); /* Retrieves 'netdev''s Ethernet address into 'mac'. * * This address will be advertised as 'netdev''s MAC address through the * OpenFlow protocol, among other uses. */ int (*get_etheraddr)(const struct netdev *netdev, uint8_t mac[6]); /* Retrieves 'netdev''s MTU into '*mtup'. * * The MTU is the maximum size of transmitted (and received) packets, in * bytes, not including the hardware header; thus, this is typically 1500 * bytes for Ethernet devices. * * 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 (*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. * * The desired semantics of the ifindex value are a combination of those * specified by POSIX for if_nametoindex() and by SNMP for ifIndex. An * ifindex value should be unique within a host and remain stable at least * until reboot. SNMP says an ifindex "ranges between 1 and the value of * ifNumber" but many systems do not follow this rule anyhow. * * This function may be set to null if it would always return -EOPNOTSUPP. */ int (*get_ifindex)(const struct netdev *netdev); /* Sets 'carrier' to true if carrier is active (link light is on) on * 'netdev'. * * May be null if device does not provide carrier status (will be always * up as long as device is up). */ int (*get_carrier)(const struct netdev *netdev, bool *carrier); /* Returns the number of times 'netdev''s carrier has changed since being * initialized. * * If null, callers will assume the number of carrier resets is zero. */ long long int (*get_carrier_resets)(const struct netdev *netdev); /* 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. * * Most network devices won't support this feature and will set this * function pointer to NULL, which is equivalent to returning EOPNOTSUPP. */ int (*set_miimon_interval)(struct netdev *netdev, long long int interval); /* Retrieves current device stats for 'netdev' into 'stats'. * * A network device that supports some statistics but not others, it should * set the values of the unsupported statistics to all-1-bits * (UINT64_MAX). */ int (*get_stats)(const struct netdev *netdev, struct netdev_stats *); /* Sets the device stats for 'netdev' to 'stats'. * * Most network devices won't support this feature and will set this * function pointer to NULL, which is equivalent to returning EOPNOTSUPP. * * Some network devices might only allow setting their stats to 0. */ int (*set_stats)(struct netdev *netdev, const struct netdev_stats *); /* Stores the features supported by 'netdev' into each of '*current', * '*advertised', '*supported', and '*peer'. Each value is a bitmap of * NETDEV_F_* bits. * * This function may be set to null if it would always return EOPNOTSUPP. */ int (*get_features)(const struct netdev *netdev, enum netdev_features *current, enum netdev_features *advertised, enum netdev_features *supported, enum netdev_features *peer); /* Set the features advertised by 'netdev' to 'advertise', which is a * set of NETDEV_F_* bits. * * This function may be set to null for a network device that does not * support configuring advertisements. */ int (*set_advertisements)(struct netdev *netdev, enum netdev_features advertise); /* Attempts to set input rate limiting (policing) policy, such that up to * 'kbits_rate' kbps of traffic is accepted, with a maximum accumulative * burst size of 'kbits' kb. * * This function may be set to null if policing is not supported. */ int (*set_policing)(struct netdev *netdev, unsigned int kbits_rate, unsigned int kbits_burst); /* Adds to 'types' all of the forms of QoS supported by 'netdev', or leaves * it empty if 'netdev' does not support QoS. Any names added to 'types' * should be documented as valid for the "type" column in the "QoS" table * in vswitchd/vswitch.xml (which is built as ovs-vswitchd.conf.db(8)). * * Every network device must support disabling QoS with a type of "", but * this function must not add "" to 'types'. * * The caller is responsible for initializing 'types' (e.g. with * sset_init()) before calling this function. The caller retains ownership * of 'types'. * * May be NULL if 'netdev' does not support QoS at all. */ int (*get_qos_types)(const struct netdev *netdev, struct sset *types); /* Queries 'netdev' for its capabilities regarding the specified 'type' of * QoS. On success, initializes 'caps' with the QoS capabilities. * * Should return EOPNOTSUPP if 'netdev' does not support 'type'. May be * NULL if 'netdev' does not support QoS at all. */ int (*get_qos_capabilities)(const struct netdev *netdev, const char *type, struct netdev_qos_capabilities *caps); /* Queries 'netdev' about its currently configured form of QoS. If * successful, stores the name of the current form of QoS into '*typep' * and any details of configuration as string key-value pairs in * 'details'. * * A '*typep' of "" indicates that QoS is currently disabled on 'netdev'. * * The caller initializes 'details' before calling this function. The * caller takes ownership of the string key-values pairs added to * 'details'. * * The netdev retains ownership of '*typep'. * * '*typep' will be one of the types returned by netdev_get_qos_types() for * 'netdev'. The contents of 'details' should be documented as valid for * '*typep' in the "other_config" column in the "QoS" 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 (*get_qos)(const struct netdev *netdev, const char **typep, struct smap *details); /* Attempts to reconfigure QoS on 'netdev', changing the form of QoS to * 'type' with details of configuration from 'details'. * * On error, the previous QoS configuration is retained. * * When this function changes the type of QoS (not just 'details'), this * also resets all queue configuration for 'netdev' to their defaults * (which depend on the specific type of QoS). Otherwise, the queue * configuration for 'netdev' is unchanged. * * 'type' should be "" (to disable QoS) or one of the types returned by * netdev_get_qos_types() for 'netdev'. The contents of 'details' should * be documented as valid for the given 'type' in the "other_config" column * in the "QoS" 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 (*set_qos)(struct netdev *netdev, const char *type, const struct smap *details); /* Queries 'netdev' for information about the queue numbered 'queue_id'. * If successful, adds that information as string key-value pairs to * 'details'. Returns 0 if successful, otherwise a positive errno value. * * Should return EINVAL if 'queue_id' is greater than or equal to the * number of supported queues (as reported in the 'n_queues' member of * struct netdev_qos_capabilities by 'get_qos_capabilities'). * * The caller initializes '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)). */ int (*get_queue)(const struct netdev *netdev, unsigned int queue_id, struct smap *details); /* Configures the queue numbered 'queue_id' on 'netdev' with the key-value * string pairs in 'details'. The 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)). Returns 0 if successful, otherwise a positive * errno value. On failure, the given queue's configuration should be * unmodified. * * Should return EINVAL if 'queue_id' is greater than or equal to the * number of supported queues (as reported in the 'n_queues' member of * struct netdev_qos_capabilities by 'get_qos_capabilities'), or if * 'details' is invalid for the type of queue. * * This function does not modify 'details', and the caller retains * ownership of it. * * May be NULL if 'netdev' does not support QoS at all. */ int (*set_queue)(struct netdev *netdev, unsigned int queue_id, const struct smap *details); /* Attempts to delete the queue numbered 'queue_id' from 'netdev'. * * Should return EINVAL if 'queue_id' is greater than or equal to the * number of supported queues (as reported in the 'n_queues' member of * struct netdev_qos_capabilities by 'get_qos_capabilities'). Should * return EOPNOTSUPP if 'queue_id' is valid but may not be deleted (e.g. if * 'netdev' has a fixed set of queues with the current QoS mode). * * May be NULL if 'netdev' does not support QoS at all, or if all of its * QoS modes have fixed sets of queues. */ int (*delete_queue)(struct netdev *netdev, unsigned int queue_id); /* Obtains statistics about 'queue_id' on 'netdev'. Fills 'stats' with the * queue's statistics. May set individual members of 'stats' to all-1-bits * if the statistic is unavailable. * * May be NULL if 'netdev' does not support QoS at all. */ 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); /* 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 * iteration is unspecified, but (when successful) each queue must be * visited exactly once. * * 'cb' will not modify or free the statistics passed in. */ int (*dump_queue_stats)(const struct netdev *netdev, void (*cb)(unsigned int queue_id, struct netdev_queue_stats *, void *aux), void *aux); /* If 'netdev' has an assigned IPv4 address, sets '*address' to that * address and '*netmask' to the associated netmask. * * The following error values have well-defined meanings: * * - EADDRNOTAVAIL: 'netdev' has no assigned IPv4 address. * * - EOPNOTSUPP: No IPv4 network stack attached to 'netdev'. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*get_in4)(const struct netdev *netdev, struct in_addr *address, struct in_addr *netmask); /* Assigns 'addr' as 'netdev''s IPv4 address and 'mask' as its netmask. If * 'addr' is INADDR_ANY, 'netdev''s IPv4 address is cleared. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*set_in4)(struct netdev *netdev, struct in_addr addr, struct in_addr mask); /* If 'netdev' has an assigned IPv6 address, sets '*in6' to that address. * * The following error values have well-defined meanings: * * - EADDRNOTAVAIL: 'netdev' has no assigned IPv6 address. * * - EOPNOTSUPP: No IPv6 network stack attached to 'netdev'. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*get_in6)(const struct netdev *netdev, struct in6_addr *in6); /* Adds 'router' as a default IP gateway for the TCP/IP stack that * corresponds to 'netdev'. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*add_router)(struct netdev *netdev, struct in_addr router); /* Looks up the next hop for 'host'. If succesful, 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 * '*netdev_name' (by calling free()). * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*get_next_hop)(const struct in_addr *host, struct in_addr *next_hop, char **netdev_name); /* Retrieves driver information of the device. * * Populates 'sh' with key-value pairs representing the status of the * device. Driver info is a set of key-value string pairs * representing netdev type specific information. For more information see * ovs-vswitchd.conf.db(5). * * The caller is responsible for destroying 'smap' and its data. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ int (*get_drv_info)(const struct netdev *netdev, struct smap *smap); /* Looks up the ARP table entry for 'ip' on 'netdev' and stores the * corresponding MAC address in 'mac'. A return value of ENXIO, in * particular, indicates that there is no ARP table entry for 'ip' on * 'netdev'. * * This function may be set to null if it would always return EOPNOTSUPP * anyhow. */ 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.) * * 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'. * * 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 *); 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__ extern const struct netdev_class netdev_bsd_class; #endif #ifdef __cplusplus } #endif #endif /* netdev.h */