diff mbox series

[net-next,11/15] ethtool: set device ring sizes with RINGS_SET request

Message ID ec91e4c53d75ec8e499ecaec36948674b2ef07cc.1583962006.git.mkubecek@suse.cz
State Changes Requested
Delegated to: David Miller
Headers show
Series ethtool netlink interface, part 3 | expand

Commit Message

Michal Kubecek March 11, 2020, 9:40 p.m. UTC 
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.

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
---
 Documentation/networking/ethtool-netlink.rst | 23 +++++-
 include/uapi/linux/ethtool_netlink.h         |  1 +
 net/ethtool/netlink.c                        |  5 ++
 net/ethtool/netlink.h                        |  1 +
 net/ethtool/rings.c                          | 87 ++++++++++++++++++++
 5 files changed, 116 insertions(+), 1 deletion(-)

Comments

Jakub Kicinski March 11, 2020, 11:22 p.m. UTC | #1 
On Wed, 11 Mar 2020 22:40:58 +0100 (CET) Michal Kubecek wrote:
> +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;
> +	if (!ops->get_ringparam || !ops->set_ringparam)
> +		return -EOPNOTSUPP;

Leaking the dev reference here?

> +
> +	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();
> +	dev_put(dev);
> +	return ret;
> +}
diff mbox series

Patch

diff --git a/Documentation/networking/ethtool-netlink.rst b/Documentation/networking/ethtool-netlink.rst
index 798c2f97d89b..ba31ae8f1feb 100644
--- a/Documentation/networking/ethtool-netlink.rst
+++ b/Documentation/networking/ethtool-netlink.rst
@@ -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``
diff --git a/include/uapi/linux/ethtool_netlink.h b/include/uapi/linux/ethtool_netlink.h
index 7cd220f8cf73..ae71801b7aac 100644
--- a/include/uapi/linux/ethtool_netlink.h
+++ b/include/uapi/linux/ethtool_netlink.h
@@ -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,
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index 0dc25a490450..6a1ac8897a7e 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -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[] = {
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 01761932ed15..b30426d01890 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -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 */
diff --git a/net/ethtool/rings.c b/net/ethtool/rings.c
index 945b2323daff..56e628456619 100644
--- a/net/ethtool/rings.c
+++ b/net/ethtool/rings.c
@@ -97,3 +97,90 @@  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;
+	if (!ops->get_ringparam || !ops->set_ringparam)
+		return -EOPNOTSUPP;
+
+	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();
+	dev_put(dev);
+	return ret;
+}