Commit 172265b4 authored by Maxime Chevallier's avatar Maxime Chevallier Committed by Jakub Kicinski
Browse files

net: ethtool: Introduce per-PHY DUMP operations 



ethnl commands that target a phy_device need a DUMP implementation that
will fill the reply for every PHY behind a netdev. We therefore need to
iterate over the dev->topo to list them.

When multiple PHYs are behind the same netdev, it's also useful to
perform DUMP with a filter on a given netdev, to get the capability of
every PHY.

Implement dedicated genl ->start(), ->dumpit() and ->done() operations
for PHY-targetting command, allowing filtered dumps and using a dump
context that keep track of the PHY iteration for multi-message dump.

PSE-PD and PLCA are converted to this new set of ops along the way.

Signed-off-by: default avatarMaxime Chevallier <maxime.chevallier@bootlin.com>
Link: https://patch.msgid.link/20250502085242.248645-2-maxime.chevallier@bootlin.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 953d9480

net/ethtool/netlink.c

+194 −9
Original line number Diff line number Diff line
@@ -357,6 +357,18 @@ struct ethnl_dump_ctx { 
	unsigned long			pos_ifindex;

};



/**

 * struct ethnl_perphy_dump_ctx - context for dumpit() PHY-aware callbacks

 * @ethnl_ctx: generic ethnl context

 * @ifindex: For Filtered DUMP requests, the ifindex of the targeted netdev

 * @pos_phyindex: iterator position for multi-msg DUMP

 */

struct ethnl_perphy_dump_ctx {

	struct ethnl_dump_ctx	ethnl_ctx;

	unsigned int		ifindex;

	unsigned long		pos_phyindex;

};



static const struct ethnl_request_ops *

ethnl_default_requests[__ETHTOOL_MSG_USER_CNT] = {

	[ETHTOOL_MSG_STRSET_GET]	= &ethnl_strset_request_ops,
@@ -407,6 +419,12 @@ static struct ethnl_dump_ctx *ethnl_dump_context(struct netlink_callback *cb) 
	return (struct ethnl_dump_ctx *)cb->ctx;

}



static struct ethnl_perphy_dump_ctx *

ethnl_perphy_dump_context(struct netlink_callback *cb)

{

	return (struct ethnl_perphy_dump_ctx *)cb->ctx;

}



/**

 * ethnl_default_parse() - Parse request message

 * @req_info:    pointer to structure to put data into
@@ -662,6 +680,173 @@ static int ethnl_default_start(struct netlink_callback *cb) 
	return ret;

}



/* per-PHY ->start() handler for GET requests */

static int ethnl_perphy_start(struct netlink_callback *cb)

{

	struct ethnl_perphy_dump_ctx *phy_ctx = ethnl_perphy_dump_context(cb);

	const struct genl_dumpit_info *info = genl_dumpit_info(cb);

	struct ethnl_dump_ctx *ctx = &phy_ctx->ethnl_ctx;

	struct ethnl_reply_data *reply_data;

	const struct ethnl_request_ops *ops;

	struct ethnl_req_info *req_info;

	struct genlmsghdr *ghdr;

	int ret;



	BUILD_BUG_ON(sizeof(*ctx) > sizeof(cb->ctx));



	ghdr = nlmsg_data(cb->nlh);

	ops = ethnl_default_requests[ghdr->cmd];

	if (WARN_ONCE(!ops, "cmd %u has no ethnl_request_ops\n", ghdr->cmd))

		return -EOPNOTSUPP;

	req_info = kzalloc(ops->req_info_size, GFP_KERNEL);

	if (!req_info)

		return -ENOMEM;

	reply_data = kmalloc(ops->reply_data_size, GFP_KERNEL);

	if (!reply_data) {

		ret = -ENOMEM;

		goto free_req_info;

	}



	/* Unlike per-dev dump, don't ignore dev. The dump handler

	 * will notice it and dump PHYs from given dev. We only keep track of

	 * the dev's ifindex, .dumpit() will grab and release the netdev itself.

	 */

	ret = ethnl_default_parse(req_info, &info->info, ops, false);

	if (req_info->dev) {

		phy_ctx->ifindex = req_info->dev->ifindex;

		netdev_put(req_info->dev, &req_info->dev_tracker);

		req_info->dev = NULL;

	}

	if (ret < 0)

		goto free_reply_data;



	ctx->ops = ops;

	ctx->req_info = req_info;

	ctx->reply_data = reply_data;

	ctx->pos_ifindex = 0;



	return 0;



free_reply_data:

	kfree(reply_data);

free_req_info:

	kfree(req_info);



	return ret;

}



static int ethnl_perphy_dump_one_dev(struct sk_buff *skb,

				     struct ethnl_perphy_dump_ctx *ctx,

				     const struct genl_info *info)

{

	struct ethnl_dump_ctx *ethnl_ctx = &ctx->ethnl_ctx;

	struct net_device *dev = ethnl_ctx->req_info->dev;

	struct phy_device_node *pdn;

	int ret;



	if (!dev->link_topo)

		return 0;



	xa_for_each_start(&dev->link_topo->phys, ctx->pos_phyindex, pdn,

			  ctx->pos_phyindex) {

		ethnl_ctx->req_info->phy_index = ctx->pos_phyindex;



		/* We can re-use the original dump_one as ->prepare_data in

		 * commands use ethnl_req_get_phydev(), which gets the PHY from

		 * the req_info->phy_index

		 */

		ret = ethnl_default_dump_one(skb, dev, ethnl_ctx, info);

		if (ret)

			return ret;

	}



	ctx->pos_phyindex = 0;



	return 0;

}



static int ethnl_perphy_dump_all_dev(struct sk_buff *skb,

				     struct ethnl_perphy_dump_ctx *ctx,

				     const struct genl_info *info)

{

	struct ethnl_dump_ctx *ethnl_ctx = &ctx->ethnl_ctx;

	struct net *net = sock_net(skb->sk);

	netdevice_tracker dev_tracker;

	struct net_device *dev;

	int ret = 0;



	rcu_read_lock();

	for_each_netdev_dump(net, dev, ethnl_ctx->pos_ifindex) {

		netdev_hold(dev, &dev_tracker, GFP_ATOMIC);

		rcu_read_unlock();



		/* per-PHY commands use ethnl_req_get_phydev(), which needs the

		 * net_device in the req_info

		 */

		ethnl_ctx->req_info->dev = dev;

		ret = ethnl_perphy_dump_one_dev(skb, ctx, info);



		rcu_read_lock();

		netdev_put(dev, &dev_tracker);

		ethnl_ctx->req_info->dev = NULL;



		if (ret < 0 && ret != -EOPNOTSUPP) {

			if (likely(skb->len))

				ret = skb->len;

			break;

		}

		ret = 0;

	}

	rcu_read_unlock();



	return ret;

}



/* per-PHY ->dumpit() handler for GET requests. */

static int ethnl_perphy_dumpit(struct sk_buff *skb,

			       struct netlink_callback *cb)

{

	struct ethnl_perphy_dump_ctx *ctx = ethnl_perphy_dump_context(cb);

	const struct genl_dumpit_info *info = genl_dumpit_info(cb);

	struct ethnl_dump_ctx *ethnl_ctx = &ctx->ethnl_ctx;

	int ret = 0;



	if (ctx->ifindex) {

		netdevice_tracker dev_tracker;

		struct net_device *dev;



		dev = netdev_get_by_index(genl_info_net(&info->info),

					  ctx->ifindex, &dev_tracker,

					  GFP_KERNEL);

		if (!dev)

			return -ENODEV;



		ethnl_ctx->req_info->dev = dev;

		ret = ethnl_perphy_dump_one_dev(skb, ctx, genl_info_dump(cb));



		if (ret < 0 && ret != -EOPNOTSUPP && likely(skb->len))

			ret = skb->len;



		netdev_put(dev, &dev_tracker);

	} else {

		ret = ethnl_perphy_dump_all_dev(skb, ctx, genl_info_dump(cb));

	}



	return ret;

}



/* per-PHY ->done() handler for GET requests */

static int ethnl_perphy_done(struct netlink_callback *cb)

{

	struct ethnl_perphy_dump_ctx *ctx = ethnl_perphy_dump_context(cb);

	struct ethnl_dump_ctx *ethnl_ctx = &ctx->ethnl_ctx;



	kfree(ethnl_ctx->reply_data);

	kfree(ethnl_ctx->req_info);



	return 0;

}



/* default ->done() handler for GET requests */

static int ethnl_default_done(struct netlink_callback *cb)

{
@@ -1200,9 +1385,9 @@ static const struct genl_ops ethtool_genl_ops[] = { 
	{

		.cmd	= ETHTOOL_MSG_PSE_GET,

		.doit	= ethnl_default_doit,

		.start	= ethnl_default_start,

		.dumpit	= ethnl_default_dumpit,

		.done	= ethnl_default_done,

		.start	= ethnl_perphy_start,

		.dumpit	= ethnl_perphy_dumpit,

		.done	= ethnl_perphy_done,

		.policy = ethnl_pse_get_policy,

		.maxattr = ARRAY_SIZE(ethnl_pse_get_policy) - 1,

	},
@@ -1224,9 +1409,9 @@ static const struct genl_ops ethtool_genl_ops[] = { 
	{

		.cmd	= ETHTOOL_MSG_PLCA_GET_CFG,

		.doit	= ethnl_default_doit,

		.start	= ethnl_default_start,

		.dumpit	= ethnl_default_dumpit,

		.done	= ethnl_default_done,

		.start	= ethnl_perphy_start,

		.dumpit	= ethnl_perphy_dumpit,

		.done	= ethnl_perphy_done,

		.policy = ethnl_plca_get_cfg_policy,

		.maxattr = ARRAY_SIZE(ethnl_plca_get_cfg_policy) - 1,

	},
@@ -1240,9 +1425,9 @@ static const struct genl_ops ethtool_genl_ops[] = { 
	{

		.cmd	= ETHTOOL_MSG_PLCA_GET_STATUS,

		.doit	= ethnl_default_doit,

		.start	= ethnl_default_start,

		.dumpit	= ethnl_default_dumpit,

		.done	= ethnl_default_done,

		.start	= ethnl_perphy_start,

		.dumpit	= ethnl_perphy_dumpit,

		.done	= ethnl_perphy_done,

		.policy = ethnl_plca_get_status_policy,

		.maxattr = ARRAY_SIZE(ethnl_plca_get_status_policy) - 1,

	},