1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * This file contains all networking devres helpers. 4 */ 5 6 #include <linux/device.h> 7 #include <linux/etherdevice.h> 8 #include <linux/netdevice.h> 9 10 struct net_device_devres { 11 struct net_device *ndev; 12 }; 13 14 static void devm_free_netdev(struct device *dev, void *this) 15 { 16 struct net_device_devres *res = this; 17 18 free_netdev(res->ndev); 19 } 20 21 struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv, 22 unsigned int txqs, unsigned int rxqs) 23 { 24 struct net_device_devres *dr; 25 26 dr = devres_alloc(devm_free_netdev, sizeof(*dr), GFP_KERNEL); 27 if (!dr) 28 return NULL; 29 30 dr->ndev = alloc_etherdev_mqs(sizeof_priv, txqs, rxqs); 31 if (!dr->ndev) { 32 devres_free(dr); 33 return NULL; 34 } 35 36 devres_add(dev, dr); 37 38 return dr->ndev; 39 } 40 EXPORT_SYMBOL(devm_alloc_etherdev_mqs); 41 42 static void devm_netdev_release(struct device *dev, void *this) 43 { 44 struct net_device_devres *res = this; 45 46 unregister_netdev(res->ndev); 47 } 48 49 static int netdev_devres_match(struct device *dev, void *this, void *match_data) 50 { 51 struct net_device_devres *res = this; 52 struct net_device *ndev = match_data; 53 54 return ndev == res->ndev; 55 } 56 57 /** 58 * devm_register_netdev - resource managed variant of register_netdev() 59 * @dev: managing device for this netdev - usually the parent device 60 * @ndev: device to register 61 * 62 * This is a devres variant of register_netdev() for which the unregister 63 * function will be call automatically when the managing device is 64 * detached. Note: the net_device used must also be resource managed by 65 * the same struct device. 66 */ 67 int devm_register_netdev(struct device *dev, struct net_device *ndev) 68 { 69 struct net_device_devres *dr; 70 int ret; 71 72 /* struct net_device must itself be managed. For now a managed netdev 73 * can only be allocated by devm_alloc_etherdev_mqs() so the check is 74 * straightforward. 75 */ 76 if (WARN_ON(!devres_find(dev, devm_free_netdev, 77 netdev_devres_match, ndev))) 78 return -EINVAL; 79 80 dr = devres_alloc(devm_netdev_release, sizeof(*dr), GFP_KERNEL); 81 if (!dr) 82 return -ENOMEM; 83 84 ret = register_netdev(ndev); 85 if (ret) { 86 devres_free(dr); 87 return ret; 88 } 89 90 dr->ndev = ndev; 91 devres_add(ndev->dev.parent, dr); 92 93 return 0; 94 } 95 EXPORT_SYMBOL(devm_register_netdev); 96