net/ethtool/linkmodes.c - linux - Git at Google

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

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

 /* LINKMODES_GET */

 struct linkmodes_req_info {
 	struct ethnl_req_info		base;
 };

 struct linkmodes_reply_data {
 	struct ethnl_reply_data		base;
 	struct ethtool_link_ksettings	ksettings;
 	struct ethtool_link_settings	*lsettings;
 	bool				peer_empty;
 };

 #define LINKMODES_REPDATA(__reply_base) \
 	container_of(__reply_base, struct linkmodes_reply_data, base)

 const struct nla_policy ethnl_linkmodes_get_policy[] = {
 	[ETHTOOL_A_LINKMODES_HEADER]		=
 		NLA_POLICY_NESTED(ethnl_header_policy),
 };

 static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
 				  struct ethnl_reply_data *reply_base,
 				  struct genl_info *info)
 {
 	struct linkmodes_reply_data *data = LINKMODES_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 && info) {
 		GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
 		goto out;
 	}

 	if (!dev->ethtool_ops->cap_link_lanes_supported)
 		data->ksettings.lanes = 0;

 	data->peer_empty =
 		bitmap_empty(data->ksettings.link_modes.lp_advertising,
 			     __ETHTOOL_LINK_MODE_MASK_NBITS);

 out:
 	ethnl_ops_complete(dev);
 	return ret;
 }

 static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
 				const struct ethnl_reply_data *reply_base)
 {
 	const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
 	const struct ethtool_link_ksettings *ksettings = &data->ksettings;
 	const struct ethtool_link_settings *lsettings = &ksettings->base;
 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
 	int len, ret;

 	len = nla_total_size(sizeof(u8)) /* LINKMODES_AUTONEG */
 		+ nla_total_size(sizeof(u32)) /* LINKMODES_SPEED */
 		+ nla_total_size(sizeof(u32)) /* LINKMODES_LANES */
 		+ nla_total_size(sizeof(u8)) /* LINKMODES_DUPLEX */
 		+ nla_total_size(sizeof(u8)) /* LINKMODES_RATE_MATCHING */
 		+ 0;
 	ret = ethnl_bitset_size(ksettings->link_modes.advertising,
 				ksettings->link_modes.supported,
 				__ETHTOOL_LINK_MODE_MASK_NBITS,
 				link_mode_names, compact);
 	if (ret < 0)
 		return ret;
 	len += ret;
 	if (!data->peer_empty) {
 		ret = ethnl_bitset_size(ksettings->link_modes.lp_advertising,
 					NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
 					link_mode_names, compact);
 		if (ret < 0)
 			return ret;
 		len += ret;
 	}

 	if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED)
 		len += nla_total_size(sizeof(u8));

 	if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED)
 		len += nla_total_size(sizeof(u8));

 	return len;
 }

 static int linkmodes_fill_reply(struct sk_buff *skb,
 				const struct ethnl_req_info *req_base,
 				const struct ethnl_reply_data *reply_base)
 {
 	const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
 	const struct ethtool_link_ksettings *ksettings = &data->ksettings;
 	const struct ethtool_link_settings *lsettings = &ksettings->base;
 	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
 	int ret;

 	if (nla_put_u8(skb, ETHTOOL_A_LINKMODES_AUTONEG, lsettings->autoneg))
 		return -EMSGSIZE;

 	ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_OURS,
 			       ksettings->link_modes.advertising,
 			       ksettings->link_modes.supported,
 			       __ETHTOOL_LINK_MODE_MASK_NBITS, link_mode_names,
 			       compact);
 	if (ret < 0)
 		return -EMSGSIZE;
 	if (!data->peer_empty) {
 		ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_PEER,
 				       ksettings->link_modes.lp_advertising,
 				       NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
 				       link_mode_names, compact);
 		if (ret < 0)
 			return -EMSGSIZE;
 	}

 	if (nla_put_u32(skb, ETHTOOL_A_LINKMODES_SPEED, lsettings->speed) ||
 	    nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
 		return -EMSGSIZE;

 	if (ksettings->lanes &&
 	    nla_put_u32(skb, ETHTOOL_A_LINKMODES_LANES, ksettings->lanes))
 		return -EMSGSIZE;

 	if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED &&
 	    nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
 		       lsettings->master_slave_cfg))
 		return -EMSGSIZE;

 	if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED &&
 	    nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE,
 		       lsettings->master_slave_state))
 		return -EMSGSIZE;

 	if (nla_put_u8(skb, ETHTOOL_A_LINKMODES_RATE_MATCHING,
 		       lsettings->rate_matching))
 		return -EMSGSIZE;

 	return 0;
 }

 const struct ethnl_request_ops ethnl_linkmodes_request_ops = {
 	.request_cmd		= ETHTOOL_MSG_LINKMODES_GET,
 	.reply_cmd		= ETHTOOL_MSG_LINKMODES_GET_REPLY,
 	.hdr_attr		= ETHTOOL_A_LINKMODES_HEADER,
 	.req_info_size		= sizeof(struct linkmodes_req_info),
 	.reply_data_size	= sizeof(struct linkmodes_reply_data),

 	.prepare_data		= linkmodes_prepare_data,
 	.reply_size		= linkmodes_reply_size,
 	.fill_reply		= linkmodes_fill_reply,
 };

 /* LINKMODES_SET */

 const struct nla_policy ethnl_linkmodes_set_policy[] = {
 	[ETHTOOL_A_LINKMODES_HEADER]		=
 		NLA_POLICY_NESTED(ethnl_header_policy),
 	[ETHTOOL_A_LINKMODES_AUTONEG]		= { .type = NLA_U8 },
 	[ETHTOOL_A_LINKMODES_OURS]		= { .type = NLA_NESTED },
 	[ETHTOOL_A_LINKMODES_SPEED]		= { .type = NLA_U32 },
 	[ETHTOOL_A_LINKMODES_DUPLEX]		= { .type = NLA_U8 },
 	[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG]	= { .type = NLA_U8 },
 	[ETHTOOL_A_LINKMODES_LANES]		= NLA_POLICY_RANGE(NLA_U32, 1, 8),
 };

 /* Set advertised link modes to all supported modes matching requested speed,
  * lanes and duplex values. Called when autonegotiation is on, speed, lanes or
  * duplex is requested but no link mode change. This is done in userspace with
  * ioctl() interface, move it into kernel for netlink.
  * Returns true if advertised modes bitmap was modified.
  */
 static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
 				 bool req_speed, bool req_lanes, bool req_duplex)
 {
 	unsigned long *advertising = ksettings->link_modes.advertising;
 	unsigned long *supported = ksettings->link_modes.supported;
 	DECLARE_BITMAP(old_adv, __ETHTOOL_LINK_MODE_MASK_NBITS);
 	unsigned int i;

 	bitmap_copy(old_adv, advertising, __ETHTOOL_LINK_MODE_MASK_NBITS);

 	for (i = 0; i < __ETHTOOL_LINK_MODE_MASK_NBITS; i++) {
 		const struct link_mode_info *info = &link_mode_params[i];

 		if (info->speed == SPEED_UNKNOWN)
 			continue;
 		if (test_bit(i, supported) &&
 		    (!req_speed || info->speed == ksettings->base.speed) &&
 		    (!req_lanes || info->lanes == ksettings->lanes) &&
 		    (!req_duplex || info->duplex == ksettings->base.duplex))
 			set_bit(i, advertising);
 		else
 			clear_bit(i, advertising);
 	}

 	return !bitmap_equal(old_adv, advertising,
 			     __ETHTOOL_LINK_MODE_MASK_NBITS);
 }

 static bool ethnl_validate_master_slave_cfg(u8 cfg)
 {
 	switch (cfg) {
 	case MASTER_SLAVE_CFG_MASTER_PREFERRED:
 	case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
 	case MASTER_SLAVE_CFG_MASTER_FORCE:
 	case MASTER_SLAVE_CFG_SLAVE_FORCE:
 		return true;
 	}

 	return false;
 }

 static int ethnl_check_linkmodes(struct genl_info *info, struct nlattr **tb)
 {
 	const struct nlattr *master_slave_cfg, *lanes_cfg;

 	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
 	if (master_slave_cfg &&
 	    !ethnl_validate_master_slave_cfg(nla_get_u8(master_slave_cfg))) {
 		NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
 				    "master/slave value is invalid");
 		return -EOPNOTSUPP;
 	}

 	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
 	if (lanes_cfg && !is_power_of_2(nla_get_u32(lanes_cfg))) {
 		NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
 				    "lanes value is invalid");
 		return -EINVAL;
 	}

 	return 0;
 }

 static int ethnl_update_linkmodes(struct genl_info *info, struct nlattr **tb,
 				  struct ethtool_link_ksettings *ksettings,
 				  bool *mod, const struct net_device *dev)
 {
 	struct ethtool_link_settings *lsettings = &ksettings->base;
 	bool req_speed, req_lanes, req_duplex;
 	const struct nlattr *master_slave_cfg, *lanes_cfg;
 	int ret;

 	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
 	if (master_slave_cfg) {
 		if (lsettings->master_slave_cfg == MASTER_SLAVE_CFG_UNSUPPORTED) {
 			NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
 					    "master/slave configuration not supported by device");
 			return -EOPNOTSUPP;
 		}
 	}

 	*mod = false;
 	req_speed = tb[ETHTOOL_A_LINKMODES_SPEED];
 	req_lanes = tb[ETHTOOL_A_LINKMODES_LANES];
 	req_duplex = tb[ETHTOOL_A_LINKMODES_DUPLEX];

 	ethnl_update_u8(&lsettings->autoneg, tb[ETHTOOL_A_LINKMODES_AUTONEG],
 			mod);

 	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
 	if (lanes_cfg) {
 		/* If autoneg is off and lanes parameter is not supported by the
 		 * driver, return an error.
 		 */
 		if (!lsettings->autoneg &&
 		    !dev->ethtool_ops->cap_link_lanes_supported) {
 			NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
 					    "lanes configuration not supported by device");
 			return -EOPNOTSUPP;
 		}
 	} else if (!lsettings->autoneg) {
 		/* If autoneg is off and lanes parameter is not passed from user,
 		 * set the lanes parameter to 0.
 		 */
 		ksettings->lanes = 0;
 	}

 	ret = ethnl_update_bitset(ksettings->link_modes.advertising,
 				  __ETHTOOL_LINK_MODE_MASK_NBITS,
 				  tb[ETHTOOL_A_LINKMODES_OURS], link_mode_names,
 				  info->extack, mod);
 	if (ret < 0)
 		return ret;
 	ethnl_update_u32(&lsettings->speed, tb[ETHTOOL_A_LINKMODES_SPEED],
 			 mod);
 	ethnl_update_u32(&ksettings->lanes, lanes_cfg, mod);
 	ethnl_update_u8(&lsettings->duplex, tb[ETHTOOL_A_LINKMODES_DUPLEX],
 			mod);
 	ethnl_update_u8(&lsettings->master_slave_cfg, master_slave_cfg, mod);

 	if (!tb[ETHTOOL_A_LINKMODES_OURS] && lsettings->autoneg &&
 	    (req_speed || req_lanes || req_duplex) &&
 	    ethnl_auto_linkmodes(ksettings, req_speed, req_lanes, req_duplex))
 		*mod = true;

 	return 0;
 }

 int ethnl_set_linkmodes(struct sk_buff *skb, struct genl_info *info)
 {
 	struct ethtool_link_ksettings ksettings = {};
 	struct ethnl_req_info req_info = {};
 	struct nlattr **tb = info->attrs;
 	struct net_device *dev;
 	bool mod = false;
 	int ret;

 	ret = ethnl_check_linkmodes(info, tb);
 	if (ret < 0)
 		return ret;

 	ret = ethnl_parse_header_dev_get(&req_info,
 					 tb[ETHTOOL_A_LINKMODES_HEADER],
 					 genl_info_net(info), info->extack,
 					 true);
 	if (ret < 0)
 		return ret;
 	dev = req_info.dev;
 	ret = -EOPNOTSUPP;
 	if (!dev->ethtool_ops->get_link_ksettings ||
 	    !dev->ethtool_ops->set_link_ksettings)
 		goto out_dev;

 	rtnl_lock();
 	ret = ethnl_ops_begin(dev);
 	if (ret < 0)
 		goto out_rtnl;

 	ret = __ethtool_get_link_ksettings(dev, &ksettings);
 	if (ret < 0) {
 		GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
 		goto out_ops;
 	}

 	ret = ethnl_update_linkmodes(info, tb, &ksettings, &mod, dev);
 	if (ret < 0)
 		goto out_ops;

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

 out_ops:
 	ethnl_ops_complete(dev);
 out_rtnl:
 	rtnl_unlock();
 out_dev:
 	ethnl_parse_header_dev_put(&req_info);
 	return ret;
 }
	// SPDX-License-Identifier: GPL-2.0-only

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

	/* LINKMODES_GET */

	struct linkmodes_req_info {
	struct ethnl_req_info base;
	};

	struct linkmodes_reply_data {
	struct ethnl_reply_data base;
	struct ethtool_link_ksettings ksettings;
	struct ethtool_link_settings *lsettings;
	bool peer_empty;
	};

	#define LINKMODES_REPDATA(__reply_base) \
	container_of(__reply_base, struct linkmodes_reply_data, base)

	const struct nla_policy ethnl_linkmodes_get_policy[] = {
	[ETHTOOL_A_LINKMODES_HEADER] =
	NLA_POLICY_NESTED(ethnl_header_policy),
	};

	static int linkmodes_prepare_data(const struct ethnl_req_info *req_base,
	struct ethnl_reply_data *reply_base,
	struct genl_info *info)
	{
	struct linkmodes_reply_data *data = LINKMODES_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 && info) {
	GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
	goto out;
	}

	if (!dev->ethtool_ops->cap_link_lanes_supported)
	data->ksettings.lanes = 0;

	data->peer_empty =
	bitmap_empty(data->ksettings.link_modes.lp_advertising,
	__ETHTOOL_LINK_MODE_MASK_NBITS);

	out:
	ethnl_ops_complete(dev);
	return ret;
	}

	static int linkmodes_reply_size(const struct ethnl_req_info *req_base,
	const struct ethnl_reply_data *reply_base)
	{
	const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
	const struct ethtool_link_ksettings *ksettings = &data->ksettings;
	const struct ethtool_link_settings *lsettings = &ksettings->base;
	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
	int len, ret;

	len = nla_total_size(sizeof(u8)) /* LINKMODES_AUTONEG */
	+ nla_total_size(sizeof(u32)) /* LINKMODES_SPEED */
	+ nla_total_size(sizeof(u32)) /* LINKMODES_LANES */
	+ nla_total_size(sizeof(u8)) /* LINKMODES_DUPLEX */
	+ nla_total_size(sizeof(u8)) /* LINKMODES_RATE_MATCHING */
	+ 0;
	ret = ethnl_bitset_size(ksettings->link_modes.advertising,
	ksettings->link_modes.supported,
	__ETHTOOL_LINK_MODE_MASK_NBITS,
	link_mode_names, compact);
	if (ret < 0)
	return ret;
	len += ret;
	if (!data->peer_empty) {
	ret = ethnl_bitset_size(ksettings->link_modes.lp_advertising,
	NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
	link_mode_names, compact);
	if (ret < 0)
	return ret;
	len += ret;
	}

	if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED)
	len += nla_total_size(sizeof(u8));

	if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED)
	len += nla_total_size(sizeof(u8));

	return len;
	}

	static int linkmodes_fill_reply(struct sk_buff *skb,
	const struct ethnl_req_info *req_base,
	const struct ethnl_reply_data *reply_base)
	{
	const struct linkmodes_reply_data *data = LINKMODES_REPDATA(reply_base);
	const struct ethtool_link_ksettings *ksettings = &data->ksettings;
	const struct ethtool_link_settings *lsettings = &ksettings->base;
	bool compact = req_base->flags & ETHTOOL_FLAG_COMPACT_BITSETS;
	int ret;

	if (nla_put_u8(skb, ETHTOOL_A_LINKMODES_AUTONEG, lsettings->autoneg))
	return -EMSGSIZE;

	ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_OURS,
	ksettings->link_modes.advertising,
	ksettings->link_modes.supported,
	__ETHTOOL_LINK_MODE_MASK_NBITS, link_mode_names,
	compact);
	if (ret < 0)
	return -EMSGSIZE;
	if (!data->peer_empty) {
	ret = ethnl_put_bitset(skb, ETHTOOL_A_LINKMODES_PEER,
	ksettings->link_modes.lp_advertising,
	NULL, __ETHTOOL_LINK_MODE_MASK_NBITS,
	link_mode_names, compact);
	if (ret < 0)
	return -EMSGSIZE;
	}

	if (nla_put_u32(skb, ETHTOOL_A_LINKMODES_SPEED, lsettings->speed) \|\|
	nla_put_u8(skb, ETHTOOL_A_LINKMODES_DUPLEX, lsettings->duplex))
	return -EMSGSIZE;

	if (ksettings->lanes &&
	nla_put_u32(skb, ETHTOOL_A_LINKMODES_LANES, ksettings->lanes))
	return -EMSGSIZE;

	if (lsettings->master_slave_cfg != MASTER_SLAVE_CFG_UNSUPPORTED &&
	nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG,
	lsettings->master_slave_cfg))
	return -EMSGSIZE;

	if (lsettings->master_slave_state != MASTER_SLAVE_STATE_UNSUPPORTED &&
	nla_put_u8(skb, ETHTOOL_A_LINKMODES_MASTER_SLAVE_STATE,
	lsettings->master_slave_state))
	return -EMSGSIZE;

	if (nla_put_u8(skb, ETHTOOL_A_LINKMODES_RATE_MATCHING,
	lsettings->rate_matching))
	return -EMSGSIZE;

	return 0;
	}

	const struct ethnl_request_ops ethnl_linkmodes_request_ops = {
	.request_cmd = ETHTOOL_MSG_LINKMODES_GET,
	.reply_cmd = ETHTOOL_MSG_LINKMODES_GET_REPLY,
	.hdr_attr = ETHTOOL_A_LINKMODES_HEADER,
	.req_info_size = sizeof(struct linkmodes_req_info),
	.reply_data_size = sizeof(struct linkmodes_reply_data),

	.prepare_data = linkmodes_prepare_data,
	.reply_size = linkmodes_reply_size,
	.fill_reply = linkmodes_fill_reply,
	};

	/* LINKMODES_SET */

	const struct nla_policy ethnl_linkmodes_set_policy[] = {
	[ETHTOOL_A_LINKMODES_HEADER] =
	NLA_POLICY_NESTED(ethnl_header_policy),
	[ETHTOOL_A_LINKMODES_AUTONEG] = { .type = NLA_U8 },
	[ETHTOOL_A_LINKMODES_OURS] = { .type = NLA_NESTED },
	[ETHTOOL_A_LINKMODES_SPEED] = { .type = NLA_U32 },
	[ETHTOOL_A_LINKMODES_DUPLEX] = { .type = NLA_U8 },
	[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG] = { .type = NLA_U8 },
	[ETHTOOL_A_LINKMODES_LANES] = NLA_POLICY_RANGE(NLA_U32, 1, 8),
	};

	/* Set advertised link modes to all supported modes matching requested speed,
	* lanes and duplex values. Called when autonegotiation is on, speed, lanes or
	* duplex is requested but no link mode change. This is done in userspace with
	* ioctl() interface, move it into kernel for netlink.
	* Returns true if advertised modes bitmap was modified.
	*/
	static bool ethnl_auto_linkmodes(struct ethtool_link_ksettings *ksettings,
	bool req_speed, bool req_lanes, bool req_duplex)
	{
	unsigned long *advertising = ksettings->link_modes.advertising;
	unsigned long *supported = ksettings->link_modes.supported;
	DECLARE_BITMAP(old_adv, __ETHTOOL_LINK_MODE_MASK_NBITS);
	unsigned int i;

	bitmap_copy(old_adv, advertising, __ETHTOOL_LINK_MODE_MASK_NBITS);

	for (i = 0; i < __ETHTOOL_LINK_MODE_MASK_NBITS; i++) {
	const struct link_mode_info *info = &link_mode_params[i];

	if (info->speed == SPEED_UNKNOWN)
	continue;
	if (test_bit(i, supported) &&
	(!req_speed \|\| info->speed == ksettings->base.speed) &&
	(!req_lanes \|\| info->lanes == ksettings->lanes) &&
	(!req_duplex \|\| info->duplex == ksettings->base.duplex))
	set_bit(i, advertising);
	else
	clear_bit(i, advertising);
	}

	return !bitmap_equal(old_adv, advertising,
	__ETHTOOL_LINK_MODE_MASK_NBITS);
	}

	static bool ethnl_validate_master_slave_cfg(u8 cfg)
	{
	switch (cfg) {
	case MASTER_SLAVE_CFG_MASTER_PREFERRED:
	case MASTER_SLAVE_CFG_SLAVE_PREFERRED:
	case MASTER_SLAVE_CFG_MASTER_FORCE:
	case MASTER_SLAVE_CFG_SLAVE_FORCE:
	return true;
	}

	return false;
	}

	static int ethnl_check_linkmodes(struct genl_info info, struct nlattr *tb)
	{
	const struct nlattr master_slave_cfg, lanes_cfg;

	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
	if (master_slave_cfg &&
	!ethnl_validate_master_slave_cfg(nla_get_u8(master_slave_cfg))) {
	NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
	"master/slave value is invalid");
	return -EOPNOTSUPP;
	}

	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
	if (lanes_cfg && !is_power_of_2(nla_get_u32(lanes_cfg))) {
	NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
	"lanes value is invalid");
	return -EINVAL;
	}

	return 0;
	}

	static int ethnl_update_linkmodes(struct genl_info info, struct nlattr *tb,
	struct ethtool_link_ksettings *ksettings,
	bool mod, const struct net_device dev)
	{
	struct ethtool_link_settings *lsettings = &ksettings->base;
	bool req_speed, req_lanes, req_duplex;
	const struct nlattr master_slave_cfg, lanes_cfg;
	int ret;

	master_slave_cfg = tb[ETHTOOL_A_LINKMODES_MASTER_SLAVE_CFG];
	if (master_slave_cfg) {
	if (lsettings->master_slave_cfg == MASTER_SLAVE_CFG_UNSUPPORTED) {
	NL_SET_ERR_MSG_ATTR(info->extack, master_slave_cfg,
	"master/slave configuration not supported by device");
	return -EOPNOTSUPP;
	}
	}

	*mod = false;
	req_speed = tb[ETHTOOL_A_LINKMODES_SPEED];
	req_lanes = tb[ETHTOOL_A_LINKMODES_LANES];
	req_duplex = tb[ETHTOOL_A_LINKMODES_DUPLEX];

	ethnl_update_u8(&lsettings->autoneg, tb[ETHTOOL_A_LINKMODES_AUTONEG],
	mod);

	lanes_cfg = tb[ETHTOOL_A_LINKMODES_LANES];
	if (lanes_cfg) {
	/* If autoneg is off and lanes parameter is not supported by the
	* driver, return an error.
	*/
	if (!lsettings->autoneg &&
	!dev->ethtool_ops->cap_link_lanes_supported) {
	NL_SET_ERR_MSG_ATTR(info->extack, lanes_cfg,
	"lanes configuration not supported by device");
	return -EOPNOTSUPP;
	}
	} else if (!lsettings->autoneg) {
	/* If autoneg is off and lanes parameter is not passed from user,
	* set the lanes parameter to 0.
	*/
	ksettings->lanes = 0;
	}

	ret = ethnl_update_bitset(ksettings->link_modes.advertising,
	__ETHTOOL_LINK_MODE_MASK_NBITS,
	tb[ETHTOOL_A_LINKMODES_OURS], link_mode_names,
	info->extack, mod);
	if (ret < 0)
	return ret;
	ethnl_update_u32(&lsettings->speed, tb[ETHTOOL_A_LINKMODES_SPEED],
	mod);
	ethnl_update_u32(&ksettings->lanes, lanes_cfg, mod);
	ethnl_update_u8(&lsettings->duplex, tb[ETHTOOL_A_LINKMODES_DUPLEX],
	mod);
	ethnl_update_u8(&lsettings->master_slave_cfg, master_slave_cfg, mod);

	if (!tb[ETHTOOL_A_LINKMODES_OURS] && lsettings->autoneg &&
	(req_speed \|\| req_lanes \|\| req_duplex) &&
	ethnl_auto_linkmodes(ksettings, req_speed, req_lanes, req_duplex))
	*mod = true;

	return 0;
	}

	int ethnl_set_linkmodes(struct sk_buff skb, struct genl_info info)
	{
	struct ethtool_link_ksettings ksettings = {};
	struct ethnl_req_info req_info = {};
	struct nlattr **tb = info->attrs;
	struct net_device *dev;
	bool mod = false;
	int ret;

	ret = ethnl_check_linkmodes(info, tb);
	if (ret < 0)
	return ret;

	ret = ethnl_parse_header_dev_get(&req_info,
	tb[ETHTOOL_A_LINKMODES_HEADER],
	genl_info_net(info), info->extack,
	true);
	if (ret < 0)
	return ret;
	dev = req_info.dev;
	ret = -EOPNOTSUPP;
	if (!dev->ethtool_ops->get_link_ksettings \|\|
	!dev->ethtool_ops->set_link_ksettings)
	goto out_dev;

	rtnl_lock();
	ret = ethnl_ops_begin(dev);
	if (ret < 0)
	goto out_rtnl;

	ret = __ethtool_get_link_ksettings(dev, &ksettings);
	if (ret < 0) {
	GENL_SET_ERR_MSG(info, "failed to retrieve link settings");
	goto out_ops;
	}

	ret = ethnl_update_linkmodes(info, tb, &ksettings, &mod, dev);
	if (ret < 0)
	goto out_ops;

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

	out_ops:
	ethnl_ops_complete(dev);
	out_rtnl:
	rtnl_unlock();
	out_dev:
	ethnl_parse_header_dev_put(&req_info);
	return ret;
	}