// SPDX-License-Identifier: GPL-2.0-only

#include "netlink.h"
#include "common.h"

struct linkinfo_req_info {
        struct ethnl_req_info           base;
};

struct linkinfo_reply_data {
        struct ethnl_reply_data         base;
        struct ethtool_link_ksettings   ksettings;
        struct ethtool_link_settings    *lsettings;
};

#define LINKINFO_REPDATA(__reply_base) \
        container_of(__reply_base, struct linkinfo_reply_data, base)

const struct nla_policy ethnl_linkinfo_get_policy[] = {
        [ETHTOOL_A_LINKINFO_HEADER]             =
                NLA_POLICY_NESTED(ethnl_header_policy),
};

static int linkinfo_prepare_data(const struct ethnl_req_info *req_base,
                                 struct ethnl_reply_data *reply_base,
                                 const struct genl_info *info)
{
        struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base);
        struct net_device *dev = reply_base->dev;
        int ret;

        data->lsettings = &data->ksettings.base;

        ret = ethnl_ops_begin(dev);
        if (ret < 0)
                return ret;
        ret = __ethtool_get_link_ksettings(dev, &data->ksettings);
        if (ret < 0)
                GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
        ethnl_ops_complete(dev);

        return ret;
}

static int linkinfo_reply_size(const struct ethnl_req_info *req_base,
                               const struct ethnl_reply_data *reply_base)
{
        return nla_total_size(sizeof(u8)) /* LINKINFO_PORT */
                + nla_total_size(sizeof(u8)) /* LINKINFO_PHYADDR */
                + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX */
                + nla_total_size(sizeof(u8)) /* LINKINFO_TP_MDIX_CTRL */
                + nla_total_size(sizeof(u8)) /* LINKINFO_TRANSCEIVER */
                + 0;
}

static int linkinfo_fill_reply(struct sk_buff *skb,
                               const struct ethnl_req_info *req_base,
                               const struct ethnl_reply_data *reply_base)
{
        const struct linkinfo_reply_data *data = LINKINFO_REPDATA(reply_base);

        if (nla_put_u8(skb, ETHTOOL_A_LINKINFO_PORT, data->lsettings->port) ||
            nla_put_u8(skb, ETHTOOL_A_LINKINFO_PHYADDR,
                       data->lsettings->phy_address) ||
            nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX,
                       data->lsettings->eth_tp_mdix) ||
            nla_put_u8(skb, ETHTOOL_A_LINKINFO_TP_MDIX_CTRL,
                       data->lsettings->eth_tp_mdix_ctrl) ||
            nla_put_u8(skb, ETHTOOL_A_LINKINFO_TRANSCEIVER,
                       data->lsettings->transceiver))
                return -EMSGSIZE;

        return 0;
}

/* LINKINFO_SET */

const struct nla_policy ethnl_linkinfo_set_policy[] = {
        [ETHTOOL_A_LINKINFO_HEADER]             =
                NLA_POLICY_NESTED(ethnl_header_policy),
        [ETHTOOL_A_LINKINFO_PORT]               = { .type = NLA_U8 },
        [ETHTOOL_A_LINKINFO_PHYADDR]            = { .type = NLA_U8 },
        [ETHTOOL_A_LINKINFO_TP_MDIX_CTRL]       = { .type = NLA_U8 },
};

static int
ethnl_set_linkinfo_validate(struct ethnl_req_info *req_info,
                            struct genl_info *info)
{
        const struct ethtool_ops *ops = req_info->dev->ethtool_ops;

        if (!ops->get_link_ksettings || !ops->set_link_ksettings)
                return -EOPNOTSUPP;
        return 1;
}

static int
ethnl_set_linkinfo(struct ethnl_req_info *req_info, struct genl_info *info)
{
        struct ethtool_link_ksettings ksettings = {};
        struct ethtool_link_settings *lsettings;
        struct net_device *dev = req_info->dev;
        struct nlattr **tb = info->attrs;
        bool mod = false;
        int ret;

        ret = __ethtool_get_link_ksettings(dev, &ksettings);
        if (ret < 0) {
                GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
                return ret;
        }
        lsettings = &ksettings.base;

        ethnl_update_u8(&lsettings->port, tb[ETHTOOL_A_LINKINFO_PORT], &mod);
        ethnl_update_u8(&lsettings->phy_address, tb[ETHTOOL_A_LINKINFO_PHYADDR],
                        &mod);
        ethnl_update_u8(&lsettings->eth_tp_mdix_ctrl,
                        tb[ETHTOOL_A_LINKINFO_TP_MDIX_CTRL], &mod);
        if (!mod)
                return 0;

        ret = dev->ethtool_ops->set_link_ksettings(dev, &ksettings);
        if (ret < 0) {
                GENL_SET_ERR_MSG(info, "link settings update failed");
                return ret;
        }

        return 1;
}

const struct ethnl_request_ops ethnl_linkinfo_request_ops = {
        .request_cmd            = ETHTOOL_MSG_LINKINFO_GET,
        .reply_cmd              = ETHTOOL_MSG_LINKINFO_GET_REPLY,
        .hdr_attr               = ETHTOOL_A_LINKINFO_HEADER,
        .req_info_size          = sizeof(struct linkinfo_req_info),
        .reply_data_size        = sizeof(struct linkinfo_reply_data),

        .prepare_data           = linkinfo_prepare_data,
        .reply_size             = linkinfo_reply_size,
        .fill_reply             = linkinfo_fill_reply,

        .set_validate           = ethnl_set_linkinfo_validate,
        .set                    = ethnl_set_linkinfo,
        .set_ntf_cmd            = ETHTOOL_MSG_LINKINFO_NTF,
};