}
}
-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++;
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'. */
struct netdev *netdev;
int error;
- error = netdev_open_default(name, &netdev);
+ error = netdev_open(name, "system", &netdev);
if (!error) {
netdev_close(netdev);
return true;
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
* (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
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;
* '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));
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.
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);
}
}
-/* 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