// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * This file contains all networking devres helpers.
 */

#include <linux/device.h>
#include <linux/etherdevice.h>
#include <linux/netdevice.h>

struct net_device_devres {
        struct net_device *ndev;
};

static void devm_free_netdev(struct device *dev, void *this)
{
        struct net_device_devres *res = this;

        free_netdev(res->ndev);
}

struct net_device *devm_alloc_etherdev_mqs(struct device *dev, int sizeof_priv,
                                           unsigned int txqs, unsigned int rxqs)
{
        struct net_device_devres *dr;

        dr = devres_alloc(devm_free_netdev, sizeof(*dr), GFP_KERNEL);
        if (!dr)
                return NULL;

        dr->ndev = alloc_etherdev_mqs(sizeof_priv, txqs, rxqs);
        if (!dr->ndev) {
                devres_free(dr);
                return NULL;
        }

        devres_add(dev, dr);

        return dr->ndev;
}
EXPORT_SYMBOL(devm_alloc_etherdev_mqs);

static void devm_unregister_netdev(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 called 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_unregister_netdev, 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);