Commit 2fc2929e authored by Michal Kubecek's avatar Michal Kubecek Committed by David S. Miller
Browse files

ethtool: set device ring sizes with RINGS_SET request 



Implement RINGS_SET netlink request to set ring sizes of a network device.
These are traditionally set with ETHTOOL_SRINGPARAM ioctl request.

Like the ioctl implementation, the generic ethtool code checks if supplied
values do not exceed driver defined limits; if they do, first offending
attribute is reported using extack.

v2:
  - fix netdev reference leak in error path (found by Jakub Kicinsky)

Signed-off-by: default avatarMichal Kubecek <mkubecek@suse.cz>
Reviewed-by: default avatarJakub Kicinski <kuba@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent e4a1717b

Documentation/networking/ethtool-netlink.rst

+22 −1
Original line number Diff line number Diff line
@@ -194,6 +194,7 @@ Userspace to kernel: 
  ``ETHTOOL_MSG_PRIVFLAGS_GET``         get private flags

  ``ETHTOOL_MSG_PRIVFLAGS_SET``         set private flags

  ``ETHTOOL_MSG_RINGS_GET``             get ring sizes

  ``ETHTOOL_MSG_RINGS_SET``             set ring sizes

  ===================================== ================================



Kernel to userspace:
@@ -673,6 +674,26 @@ Kernel response contents: 
  ====================================  ======  ==========================





RINGS_SET

=========



Sets ring sizes like ``ETHTOOL_SRINGPARAM`` ioctl request.



Request contents:



  ====================================  ======  ==========================

  ``ETHTOOL_A_RINGS_HEADER``            nested  reply header

  ``ETHTOOL_A_RINGS_RX``                u32     size of RX ring

  ``ETHTOOL_A_RINGS_RX_MINI``           u32     size of RX mini ring

  ``ETHTOOL_A_RINGS_RX_JUMBO``          u32     size of RX jumbo ring

  ``ETHTOOL_A_RINGS_TX``                u32     size of TX ring

  ====================================  ======  ==========================



Kernel checks that requested ring sizes do not exceed limits reported by

driver. Driver may impose additional constraints and may not suspport all

attributes.





Request translation

===================
@@ -700,7 +721,7 @@ have their netlink replacement yet. 
  ``ETHTOOL_GCOALESCE``               n/a

  ``ETHTOOL_SCOALESCE``               n/a

  ``ETHTOOL_GRINGPARAM``              ``ETHTOOL_MSG_RINGS_GET``

  ``ETHTOOL_SRINGPARAM``              n/a

  ``ETHTOOL_SRINGPARAM``              ``ETHTOOL_MSG_RINGS_SET``

  ``ETHTOOL_GPAUSEPARAM``             n/a

  ``ETHTOOL_SPAUSEPARAM``             n/a

  ``ETHTOOL_GRXCSUM``                 ``ETHTOOL_MSG_FEATURES_GET``

include/uapi/linux/ethtool_netlink.h

+1 −0
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ enum { 
	ETHTOOL_MSG_PRIVFLAGS_GET,

	ETHTOOL_MSG_PRIVFLAGS_SET,

	ETHTOOL_MSG_RINGS_GET,

	ETHTOOL_MSG_RINGS_SET,



	/* add new constants above here */

	__ETHTOOL_MSG_USER_CNT,

net/ethtool/netlink.c

+5 −0
Original line number Diff line number Diff line
@@ -756,6 +756,11 @@ static const struct genl_ops ethtool_genl_ops[] = { 
		.dumpit	= ethnl_default_dumpit,

		.done	= ethnl_default_done,

	},

	{

		.cmd	= ETHTOOL_MSG_RINGS_SET,

		.flags	= GENL_UNS_ADMIN_PERM,

		.doit	= ethnl_set_rings,

	},

};



static const struct genl_multicast_group ethtool_nl_mcgrps[] = {

net/ethtool/netlink.h

+1 −0
Original line number Diff line number Diff line
@@ -347,5 +347,6 @@ int ethnl_set_debug(struct sk_buff *skb, struct genl_info *info); 
int ethnl_set_wol(struct sk_buff *skb, struct genl_info *info);

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

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

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



#endif /* _NET_ETHTOOL_NETLINK_H */

net/ethtool/rings.c

+89 −0
Original line number Diff line number Diff line
@@ -106,3 +106,92 @@ const struct ethnl_request_ops ethnl_rings_request_ops = { 
	.reply_size		= rings_reply_size,

	.fill_reply		= rings_fill_reply,

};



/* RINGS_SET */



static const struct nla_policy

rings_set_policy[ETHTOOL_A_RINGS_MAX + 1] = {

	[ETHTOOL_A_RINGS_UNSPEC]		= { .type = NLA_REJECT },

	[ETHTOOL_A_RINGS_HEADER]		= { .type = NLA_NESTED },

	[ETHTOOL_A_RINGS_RX_MAX]		= { .type = NLA_REJECT },

	[ETHTOOL_A_RINGS_RX_MINI_MAX]		= { .type = NLA_REJECT },

	[ETHTOOL_A_RINGS_RX_JUMBO_MAX]		= { .type = NLA_REJECT },

	[ETHTOOL_A_RINGS_TX_MAX]		= { .type = NLA_REJECT },

	[ETHTOOL_A_RINGS_RX]			= { .type = NLA_U32 },

	[ETHTOOL_A_RINGS_RX_MINI]		= { .type = NLA_U32 },

	[ETHTOOL_A_RINGS_RX_JUMBO]		= { .type = NLA_U32 },

	[ETHTOOL_A_RINGS_TX]			= { .type = NLA_U32 },

};



int ethnl_set_rings(struct sk_buff *skb, struct genl_info *info)

{

	struct nlattr *tb[ETHTOOL_A_RINGS_MAX + 1];

	struct ethtool_ringparam ringparam = {};

	struct ethnl_req_info req_info = {};

	const struct nlattr *err_attr;

	const struct ethtool_ops *ops;

	struct net_device *dev;

	bool mod = false;

	int ret;



	ret = nlmsg_parse(info->nlhdr, GENL_HDRLEN, tb,

			  ETHTOOL_A_RINGS_MAX, rings_set_policy,

			  info->extack);

	if (ret < 0)

		return ret;

	ret = ethnl_parse_header_dev_get(&req_info,

					 tb[ETHTOOL_A_RINGS_HEADER],

					 genl_info_net(info), info->extack,

					 true);

	if (ret < 0)

		return ret;

	dev = req_info.dev;

	ops = dev->ethtool_ops;

	ret = -EOPNOTSUPP;

	if (!ops->get_ringparam || !ops->set_ringparam)

		goto out_dev;



	rtnl_lock();

	ret = ethnl_ops_begin(dev);

	if (ret < 0)

		goto out_rtnl;

	ops->get_ringparam(dev, &ringparam);



	ethnl_update_u32(&ringparam.rx_pending, tb[ETHTOOL_A_RINGS_RX], &mod);

	ethnl_update_u32(&ringparam.rx_mini_pending,

			 tb[ETHTOOL_A_RINGS_RX_MINI], &mod);

	ethnl_update_u32(&ringparam.rx_jumbo_pending,

			 tb[ETHTOOL_A_RINGS_RX_JUMBO], &mod);

	ethnl_update_u32(&ringparam.tx_pending, tb[ETHTOOL_A_RINGS_TX], &mod);

	ret = 0;

	if (!mod)

		goto out_ops;



	/* ensure new ring parameters are within limits */

	if (ringparam.rx_pending > ringparam.rx_max_pending)

		err_attr = tb[ETHTOOL_A_RINGS_RX];

	else if (ringparam.rx_mini_pending > ringparam.rx_mini_max_pending)

		err_attr = tb[ETHTOOL_A_RINGS_RX_MINI];

	else if (ringparam.rx_jumbo_pending > ringparam.rx_jumbo_max_pending)

		err_attr = tb[ETHTOOL_A_RINGS_RX_JUMBO];

	else if (ringparam.tx_pending > ringparam.tx_max_pending)

		err_attr = tb[ETHTOOL_A_RINGS_TX];

	else

		err_attr = NULL;

	if (err_attr) {

		ret = -EINVAL;

		NL_SET_ERR_MSG_ATTR(info->extack, err_attr,

				    "requested ring size exceeeds maximum");

		goto out_ops;

	}



	ret = dev->ethtool_ops->set_ringparam(dev, &ringparam);



out_ops:

	ethnl_ops_complete(dev);

out_rtnl:

	rtnl_unlock();

out_dev:

	dev_put(dev);

	return ret;

}