From cd16627fc0468564fdd60f20ad52420b87195127 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Sat, 23 May 2020 15:27:10 +0200 Subject: [PATCH] net: devres: provide devm_register_netdev() Provide devm_register_netdev() - a device resource managed variant of register_netdev(). This new helper will only work for net_device structs that are also already managed by devres. Signed-off-by: Bartosz Golaszewski Signed-off-by: David S. Miller --- Documentation/driver-api/driver-model/devres.rst | 1 + include/linux/netdevice.h | 2 + net/devres.c | 55 ++++++++++++++++++++++++ 3 files changed, 58 insertions(+) diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst index 50df28d20fa7..fc242ed4bde5 100644 --- a/Documentation/driver-api/driver-model/devres.rst +++ b/Documentation/driver-api/driver-model/devres.rst @@ -375,6 +375,7 @@ MUX NET devm_alloc_etherdev() devm_alloc_etherdev_mqs() + devm_register_netdev() PER-CPU MEM devm_alloc_percpu() diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a18f8fdf4260..1a96e9c4ec36 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -4280,6 +4280,8 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, int register_netdev(struct net_device *dev); void unregister_netdev(struct net_device *dev); +int devm_register_netdev(struct device *dev, struct net_device *ndev); + /* General hardware address lists handling functions */ int __hw_addr_sync(struct netdev_hw_addr_list *to_list, struct netdev_hw_addr_list *from_list, int addr_len); diff --git a/net/devres.c b/net/devres.c index b97b0c5a8216..57a6a88d11f6 100644 --- a/net/devres.c +++ b/net/devres.c @@ -38,3 +38,58 @@ struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, return dr->ndev; } EXPORT_SYMBOL(devm_alloc_etherdev_mqs); + +static void devm_netdev_release(struct device *dev, void *this) +{ + struct net_device_devres *res = this; + + unregister_netdev(res->ndev); +} + +static int netdev_devres_match(struct device *dev, void *this, void *match_data) +{ + struct net_device_devres *res = this; + struct net_device *ndev = match_data; + + return ndev == res->ndev; +} + +/** + * devm_register_netdev - resource managed variant of register_netdev() + * @dev: managing device for this netdev - usually the parent device + * @ndev: device to register + * + * This is a devres variant of register_netdev() for which the unregister + * function will be call automatically when the managing device is + * detached. Note: the net_device used must also be resource managed by + * the same struct device. + */ +int devm_register_netdev(struct device *dev, struct net_device *ndev) +{ + struct net_device_devres *dr; + int ret; + + /* struct net_device must itself be managed. For now a managed netdev + * can only be allocated by devm_alloc_etherdev_mqs() so the check is + * straightforward. + */ + if (WARN_ON(!devres_find(dev, devm_free_netdev, + netdev_devres_match, ndev))) + return -EINVAL; + + dr = devres_alloc(devm_netdev_release, sizeof(*dr), GFP_KERNEL); + if (!dr) + return -ENOMEM; + + ret = register_netdev(ndev); + if (ret) { + devres_free(dr); + return ret; + } + + dr->ndev = ndev; + devres_add(ndev->dev.parent, dr); + + return 0; +} +EXPORT_SYMBOL(devm_register_netdev); -- 2.11.0