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
10struct net_device_devres {
11 struct net_device *ndev;
12};
13
14static void devm_free_netdev(struct device *dev, void *this)
15{
16 struct net_device_devres *res = this;
17
18 free_netdev(dev: res->ndev);
19}
20
21struct 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(res: dr);
33 return NULL;
34 }
35
36 devres_add(dev, res: dr);
37
38 return dr->ndev;
39}
40EXPORT_SYMBOL(devm_alloc_etherdev_mqs);
41
42static void devm_unregister_netdev(struct device *dev, void *this)
43{
44 struct net_device_devres *res = this;
45
46 unregister_netdev(dev: res->ndev);
47}
48
49static 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 called 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 */
67int 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_unregister_netdev, sizeof(*dr), GFP_KERNEL);
81 if (!dr)
82 return -ENOMEM;
83
84 ret = register_netdev(dev: ndev);
85 if (ret) {
86 devres_free(res: dr);
87 return ret;
88 }
89
90 dr->ndev = ndev;
91 devres_add(dev: ndev->dev.parent, res: dr);
92
93 return 0;
94}
95EXPORT_SYMBOL(devm_register_netdev);
96

source code of linux/net/devres.c