X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Fnetdev.c;h=cd824f84e97cc2a813060bd0861a47ebe59d3c81;hb=299016266ed13376a7d671f66d4e0181b41098e3;hp=b8592c19f9e3e1760734a593d26f933b441be380;hpb=aebf4235f3938b9e8865d4eb4a767d7584478d30;p=openvswitch diff --git a/lib/netdev.c b/lib/netdev.c index b8592c19..cd824f84 100644 --- a/lib/netdev.c +++ b/lib/netdev.c @@ -192,66 +192,42 @@ netdev_enumerate_types(struct sset *types) } } -void -update_device_args(struct netdev_dev *dev, const struct shash *args) -{ - smap_destroy(&dev->args); - smap_clone(&dev->args, args); -} - -/* Opens the network device named 'name' (e.g. "eth0") and returns zero if - * successful, otherwise a positive errno value. On success, sets '*netdevp' - * to the new network device, otherwise to null. - * - * If this is the first time the device has been opened, then create is called - * before opening. The device is created using the given type and arguments. +/* Opens the network device named 'name' (e.g. "eth0") of the specified 'type' + * (e.g. "system") and returns zero if successful, otherwise a positive errno + * value. On success, sets '*netdevp' to the new network device, otherwise to + * null. * - * '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. */ + * Some network devices may need to be configured (with netdev_set_config()) + * before they can be used. */ int -netdev_open(struct netdev_options *options, struct netdev **netdevp) +netdev_open(const char *name, const char *type, struct netdev **netdevp) { - struct shash empty_args = SHASH_INITIALIZER(&empty_args); struct netdev_dev *netdev_dev; int error; *netdevp = NULL; netdev_initialize(); - if (!options->args) { - options->args = &empty_args; - } - - netdev_dev = shash_find_data(&netdev_dev_shash, options->name); + netdev_dev = shash_find_data(&netdev_dev_shash, name); if (!netdev_dev) { const struct netdev_class *class; - class = netdev_lookup_provider(options->type); + class = netdev_lookup_provider(type); if (!class) { VLOG_WARN("could not create netdev %s of unknown type %s", - options->name, options->type); + name, type); return EAFNOSUPPORT; } - error = class->create(class, options->name, options->args, - &netdev_dev); + error = class->create(class, name, &netdev_dev); if (error) { return error; } assert(netdev_dev->netdev_class == class); - } else if (!shash_is_empty(options->args) && - !netdev_dev_args_equal(netdev_dev, options->args)) { - - VLOG_WARN("%s: attempted to open already open netdev with " - "different arguments", options->name); - return EINVAL; } - error = netdev_dev->netdev_class->open(netdev_dev, options->ethertype, - netdevp); + error = netdev_dev->netdev_class->open(netdev_dev, netdevp); if (!error) { netdev_dev->ref_cnt++; @@ -264,53 +240,49 @@ netdev_open(struct netdev_options *options, struct netdev **netdevp) return error; } -int -netdev_open_default(const char *name, struct netdev **netdevp) -{ - struct netdev_options options; - - memset(&options, 0, sizeof options); - options.name = name; - options.ethertype = NETDEV_ETH_TYPE_NONE; - - return netdev_open(&options, netdevp); -} - /* Reconfigures the device 'netdev' with 'args'. 'args' may be empty * or NULL if none are needed. */ int netdev_set_config(struct netdev *netdev, const struct shash *args) { - struct shash empty_args = SHASH_INITIALIZER(&empty_args); struct netdev_dev *netdev_dev = netdev_get_dev(netdev); - if (!args) { - args = &empty_args; - } - if (netdev_dev->netdev_class->set_config) { - if (!netdev_dev_args_equal(netdev_dev, args)) { - update_device_args(netdev_dev, args); - return netdev_dev->netdev_class->set_config(netdev_dev, args); - } - } else if (!shash_is_empty(args)) { - VLOG_WARN("%s: arguments provided to device whose configuration " - "cannot be changed", netdev_get_name(netdev)); + struct shash no_args = SHASH_INITIALIZER(&no_args); + return netdev_dev->netdev_class->set_config(netdev_dev, + args ? args : &no_args); + } else if (args && !shash_is_empty(args)) { + VLOG_WARN("%s: arguments provided to device that is not configurable", + netdev_get_name(netdev)); } return 0; } -/* Returns the current configuration for 'netdev'. This is either the - * configuration passed to netdev_open() or netdev_set_config(), or it is a - * configuration retrieved from the device itself if no configuration was - * passed to those functions. +/* Returns the current configuration for 'netdev' in 'args'. The caller must + * have already initialized 'args' with shash_init(). Returns 0 on success, in + * which case 'args' will be filled with 'netdev''s configuration. On failure + * returns a positive errno value, in which case 'args' will be empty. * - * 'netdev' retains ownership of the returned configuration. */ -const struct shash * -netdev_get_config(const struct netdev *netdev) + * The caller owns 'args' and its contents and must eventually free them with + * shash_destroy_free_data(). */ +int +netdev_get_config(const struct netdev *netdev, struct shash *args) { - return &netdev_get_dev(netdev)->args; + struct netdev_dev *netdev_dev = netdev_get_dev(netdev); + int error; + + shash_clear_free_data(args); + if (netdev_dev->netdev_class->get_config) { + error = netdev_dev->netdev_class->get_config(netdev_dev, args); + if (error) { + shash_clear_free_data(args); + } + } else { + error = 0; + } + + return error; } /* Closes and destroys 'netdev'. */ @@ -339,7 +311,7 @@ netdev_exists(const char *name) struct netdev *netdev; int error; - error = netdev_open_default(name, &netdev); + error = netdev_open(name, "system", &netdev); if (!error) { netdev_close(netdev); return true; @@ -387,6 +359,19 @@ netdev_enumerate(struct sset *sset) return error; } +/* Attempts to set up 'netdev' for receiving packets with netdev_recv(). + * Returns 0 if successful, otherwise a positive errno value. EOPNOTSUPP + * indicates that the network device does not implement packet reception + * through this interface. */ +int +netdev_listen(struct netdev *netdev) +{ + int (*listen)(struct netdev *); + + listen = netdev_get_dev(netdev)->netdev_class->listen; + return listen ? (listen)(netdev) : EOPNOTSUPP; +} + /* Attempts to receive a packet from 'netdev' into 'buffer', which the caller * must have initialized with sufficient room for the packet. The space * required to receive any packet is ETH_HEADER_LEN bytes, plus VLAN_HEADER_LEN @@ -394,6 +379,9 @@ netdev_enumerate(struct sset *sset) * (Some devices do not allow for a VLAN header, in which case VLAN_HEADER_LEN * need not be included.) * + * This function can only be expected to return a packet if ->listen() has + * been called successfully. + * * If a packet is successfully retrieved, returns 0. In this case 'buffer' is * guaranteed to contain at least ETH_TOTAL_MIN bytes. Otherwise, returns a * positive errno value. Returns EAGAIN immediately if no packet is ready to @@ -1267,7 +1255,7 @@ netdev_find_dev_by_in4(const struct in_addr *in4) SSET_FOR_EACH (name, &dev_list) { struct in_addr dev_in4; - if (!netdev_open_default(name, &netdev) + if (!netdev_open(name, "system", &netdev) && !netdev_get_in4(netdev, &dev_in4, NULL) && dev_in4.s_addr == in4->s_addr) { goto exit; @@ -1285,17 +1273,11 @@ exit: * 'netdev_class'. This function is ordinarily called from a netdev provider's * 'create' function. * - * 'args' should be the arguments that were passed to the netdev provider's - * 'create'. If an empty set of arguments was passed, and 'name' is the name - * of a network device that existed before the 'create' call, then 'args' may - * instead be the configuration for that existing device. - * * This function adds 'netdev_dev' to a netdev-owned shash, so it is * very important that 'netdev_dev' only be freed after calling * the refcount drops to zero. */ void netdev_dev_init(struct netdev_dev *netdev_dev, const char *name, - const struct shash *args, const struct netdev_class *netdev_class) { assert(!shash_find(&netdev_dev_shash, name)); @@ -1304,7 +1286,6 @@ netdev_dev_init(struct netdev_dev *netdev_dev, const char *name, netdev_dev->netdev_class = netdev_class; netdev_dev->name = xstrdup(name); netdev_dev->node = shash_add(&netdev_dev_shash, name, netdev_dev); - smap_clone(&netdev_dev->args, args); } /* Undoes the results of initialization. @@ -1322,7 +1303,6 @@ netdev_dev_uninit(struct netdev_dev *netdev_dev, bool destroy) assert(!netdev_dev->ref_cnt); shash_delete(&netdev_dev_shash, netdev_dev->node); - smap_destroy(&netdev_dev->args); if (destroy) { netdev_dev->netdev_class->destroy(netdev_dev); @@ -1382,19 +1362,6 @@ netdev_dev_get_devices(const struct netdev_class *netdev_class, } } -/* Returns true if 'args' is equivalent to the "args" field in - * 'netdev_dev', otherwise false. */ -bool -netdev_dev_args_equal(const struct netdev_dev *netdev_dev, - const struct shash *args) -{ - if (netdev_dev->netdev_class->config_equal) { - return netdev_dev->netdev_class->config_equal(netdev_dev, args); - } else { - return smap_equal(&netdev_dev->args, args); - } -} - /* Initializes 'netdev' as a instance of the netdev_dev. * * This function adds 'netdev' to a netdev-owned linked list, so it is very