ieee802154: add del interface command

This patch adds support for deleting a wpan interface via nl802154.
Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/cfg802154.h

@@ -43,6 +43,8 @@ struct cfg802154_ops {
 				    const char *name,
 				    enum nl802154_iftype type,
 				    __le64 extended_addr);
+	int	(*del_virtual_intf)(struct wpan_phy *wpan_phy,
+				    struct wpan_dev *wpan_dev);
 	int	(*set_channel)(struct wpan_phy *wpan_phy, u8 page, u8 channel);
 	int	(*set_pan_id)(struct wpan_phy *wpan_phy,
 			      struct wpan_dev *wpan_dev, u16 pan_id);

net/ieee802154/nl802154.c

@@ -583,6 +583,26 @@ static int nl802154_new_interface(struct sk_buff *skb, struct genl_info *info)
 				     type, extended_addr);
 }
 
+static int nl802154_del_interface(struct sk_buff *skb, struct genl_info *info)
+{
+	struct cfg802154_registered_device *rdev = info->user_ptr[0];
+	struct wpan_dev *wpan_dev = info->user_ptr[1];
+
+	if (!rdev->ops->del_virtual_intf)
+		return -EOPNOTSUPP;
+
+	/* If we remove a wpan device without a netdev then clear
+	 * user_ptr[1] so that nl802154_post_doit won't dereference it
+	 * to check if it needs to do dev_put(). Otherwise it crashes
+	 * since the wpan_dev has been freed, unlike with a netdev where
+	 * we need the dev_put() for the netdev to really be freed.
+	 */
+	if (!wpan_dev->netdev)
+		info->user_ptr[1] = NULL;
+
+	return rdev_del_virtual_intf(rdev, wpan_dev);
+}
+
 static int nl802154_set_channel(struct sk_buff *skb, struct genl_info *info)
 {
 	struct cfg802154_registered_device *rdev = info->user_ptr[0];
@@ -858,6 +878,14 @@ static const struct genl_ops nl802154_ops[] = {
 		.internal_flags = NL802154_FLAG_NEED_WPAN_PHY |
 				  NL802154_FLAG_NEED_RTNL,
 	},
+	{
+		.cmd = NL802154_CMD_DEL_INTERFACE,
+		.doit = nl802154_del_interface,
+		.policy = nl802154_policy,
+		.flags = GENL_ADMIN_PERM,
+		.internal_flags = NL802154_FLAG_NEED_WPAN_DEV |
+				  NL802154_FLAG_NEED_RTNL,
+	},
 	{
 		.cmd = NL802154_CMD_SET_CHANNEL,
 		.doit = nl802154_set_channel,

net/ieee802154/rdev-ops.h

@@ -28,6 +28,13 @@ rdev_add_virtual_intf(struct cfg802154_registered_device *rdev, char *name,
 					   extended_addr);
 }
 
+static inline int
+rdev_del_virtual_intf(struct cfg802154_registered_device *rdev,
+		      struct wpan_dev *wpan_dev)
+{
+	return rdev->ops->del_virtual_intf(&rdev->wpan_phy, wpan_dev);
+}
+
 static inline int
 rdev_set_channel(struct cfg802154_registered_device *rdev, u8 page, u8 channel)
 {

net/mac802154/cfg.c

@@ -57,6 +57,14 @@ ieee802154_add_iface(struct wpan_phy *phy, const char *name,
 	return 0;
 }
 
+static int
+ieee802154_del_iface(struct wpan_phy *wpan_phy, struct wpan_dev *wpan_dev)
+{
+	ieee802154_if_remove(IEEE802154_WPAN_DEV_TO_SUB_IF(wpan_dev));
+
+	return 0;
+}
+
 static int
 ieee802154_set_channel(struct wpan_phy *wpan_phy, u8 page, u8 channel)
 {
@@ -191,6 +199,7 @@ const struct cfg802154_ops mac802154_config_ops = {
 	.add_virtual_intf_deprecated = ieee802154_add_iface_deprecated,
 	.del_virtual_intf_deprecated = ieee802154_del_iface_deprecated,
 	.add_virtual_intf = ieee802154_add_iface,
+	.del_virtual_intf = ieee802154_del_iface,
 	.set_channel = ieee802154_set_channel,
 	.set_pan_id = ieee802154_set_pan_id,
 	.set_short_addr = ieee802154_set_short_addr,

net/mac802154/ieee802154_i.h

@@ -115,6 +115,12 @@ IEEE802154_DEV_TO_SUB_IF(const struct net_device *dev)
 	return netdev_priv(dev);
 }
 
+static inline struct ieee802154_sub_if_data *
+IEEE802154_WPAN_DEV_TO_SUB_IF(struct wpan_dev *wpan_dev)
+{
+	return container_of(wpan_dev, struct ieee802154_sub_if_data, wpan_dev);
+}
+
 static inline bool
 ieee802154_sdata_running(struct ieee802154_sub_if_data *sdata)
 {