Commit f6122900 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

ethtool: rss: support dumping RSS contexts 



Now that we track RSS contexts in the core we can easily dump
them. This is a major introspection improvement, as previously
the only way to find all contexts would be to try all ids
(of which there may be 2^32 - 1).

Don't use the XArray iterators (like xa_for_each_start()) as they
do not move the index past the end of the array once done, which
caused multiple bugs in Netlink dumps in the past.

Reviewed-by: default avatarEdward Cree <ecree.xilinx@gmail.com>
Reviewed-by: default avatarJoe Damato <jdamato@fastly.com>
Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent bb87f2c7

Documentation/netlink/specs/ethtool.yaml

+7 −2
Original line number Diff line number Diff line
@@ -1749,12 +1749,12 @@ operations: 


      attribute-set: rss



      do: &rss-get-op

      do:

        request:

          attributes:

            - header

            - context

        reply:

        reply: &rss-reply

          attributes:

            - header

            - context
@@ -1762,6 +1762,11 @@ operations: 
            - indir

            - hkey

            - input_xfrm

      dump:

        request:

          attributes:

            - header

        reply: *rss-reply

    -

      name: plca-get-cfg

      doc: Get PLCA params.

net/ethtool/netlink.c

+2 −0
Original line number Diff line number Diff line
@@ -1128,6 +1128,8 @@ static const struct genl_ops ethtool_genl_ops[] = { 
	{

		.cmd	= ETHTOOL_MSG_RSS_GET,

		.doit	= ethnl_default_doit,

		.start	= ethnl_rss_dump_start,

		.dumpit	= ethnl_rss_dumpit,

		.policy = ethnl_rss_get_policy,

		.maxattr = ARRAY_SIZE(ethnl_rss_get_policy) - 1,

	},

net/ethtool/netlink.h

+2 −0
Original line number Diff line number Diff line
@@ -464,6 +464,8 @@ int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info); 
int ethnl_tunnel_info_start(struct netlink_callback *cb);

int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb);

int ethnl_act_module_fw_flash(struct sk_buff *skb, struct genl_info *info);

int ethnl_rss_dump_start(struct netlink_callback *cb);

int ethnl_rss_dumpit(struct sk_buff *skb, struct netlink_callback *cb);



extern const char stats_std_names[__ETHTOOL_STATS_CNT][ETH_GSTRING_LEN];

extern const char stats_eth_phy_names[__ETHTOOL_A_STATS_ETH_PHY_CNT][ETH_GSTRING_LEN];

net/ethtool/rss.c

+135 −0
Original line number Diff line number Diff line
@@ -208,6 +208,141 @@ static void rss_cleanup_data(struct ethnl_reply_data *reply_base) 
	kfree(data->indir_table);

}



struct rss_nl_dump_ctx {

	unsigned long		ifindex;

	unsigned long		ctx_idx;



	/* User wants to only dump contexts from given ifindex */

	unsigned int		match_ifindex;

};



static struct rss_nl_dump_ctx *rss_dump_ctx(struct netlink_callback *cb)

{

	NL_ASSERT_DUMP_CTX_FITS(struct rss_nl_dump_ctx);



	return (struct rss_nl_dump_ctx *)cb->ctx;

}



int ethnl_rss_dump_start(struct netlink_callback *cb)

{

	const struct genl_info *info = genl_info_dump(cb);

	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);

	struct ethnl_req_info req_info = {};

	struct nlattr **tb = info->attrs;

	int ret;



	/* Filtering by context not supported */

	if (tb[ETHTOOL_A_RSS_CONTEXT]) {

		NL_SET_BAD_ATTR(info->extack, tb[ETHTOOL_A_RSS_CONTEXT]);

		return -EINVAL;

	}



	ret = ethnl_parse_header_dev_get(&req_info,

					 tb[ETHTOOL_A_RSS_HEADER],

					 sock_net(cb->skb->sk), cb->extack,

					 false);

	if (req_info.dev) {

		ctx->match_ifindex = req_info.dev->ifindex;

		ctx->ifindex = ctx->match_ifindex;

		ethnl_parse_header_dev_put(&req_info);

		req_info.dev = NULL;

	}



	return ret;

}



static int

rss_dump_one_ctx(struct sk_buff *skb, struct netlink_callback *cb,

		 struct net_device *dev, u32 rss_context)

{

	const struct genl_info *info = genl_info_dump(cb);

	struct rss_reply_data data = {};

	struct rss_req_info req = {};

	void *ehdr;

	int ret;



	req.rss_context = rss_context;



	ehdr = ethnl_dump_put(skb, cb, ETHTOOL_MSG_RSS_GET_REPLY);

	if (!ehdr)

		return -EMSGSIZE;



	ret = ethnl_fill_reply_header(skb, dev, ETHTOOL_A_RSS_HEADER);

	if (ret < 0)

		goto err_cancel;



	/* Context 0 is not currently storred or cached in the XArray */

	if (!rss_context)

		ret = rss_prepare_get(&req, dev, &data, info);

	else

		ret = rss_prepare_ctx(&req, dev, &data, info);

	if (ret)

		goto err_cancel;



	ret = rss_fill_reply(skb, &req.base, &data.base);

	if (ret)

		goto err_cleanup;

	genlmsg_end(skb, ehdr);



	rss_cleanup_data(&data.base);

	return 0;



err_cleanup:

	rss_cleanup_data(&data.base);

err_cancel:

	genlmsg_cancel(skb, ehdr);

	return ret;

}



static int

rss_dump_one_dev(struct sk_buff *skb, struct netlink_callback *cb,

		 struct net_device *dev)

{

	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);

	int ret;



	if (!dev->ethtool_ops->get_rxfh)

		return 0;



	if (!ctx->ctx_idx) {

		ret = rss_dump_one_ctx(skb, cb, dev, 0);

		if (ret)

			return ret;

		ctx->ctx_idx++;

	}



	for (; xa_find(&dev->ethtool->rss_ctx, &ctx->ctx_idx,

		       ULONG_MAX, XA_PRESENT); ctx->ctx_idx++) {

		ret = rss_dump_one_ctx(skb, cb, dev, ctx->ctx_idx);

		if (ret)

			return ret;

	}

	ctx->ctx_idx = 0;



	return 0;

}



int ethnl_rss_dumpit(struct sk_buff *skb, struct netlink_callback *cb)

{

	struct rss_nl_dump_ctx *ctx = rss_dump_ctx(cb);

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

	struct net_device *dev;

	int ret = 0;



	rtnl_lock();

	for_each_netdev_dump(net, dev, ctx->ifindex) {

		if (ctx->match_ifindex && ctx->match_ifindex != ctx->ifindex)

			break;



		ret = rss_dump_one_dev(skb, cb, dev);

		if (ret)

			break;

	}

	rtnl_unlock();



	return ret;

}



const struct ethnl_request_ops ethnl_rss_request_ops = {

	.request_cmd		= ETHTOOL_MSG_RSS_GET,

	.reply_cmd		= ETHTOOL_MSG_RSS_GET_REPLY,