diff mbox

[SRU,Trusty,1/5] rtnetlink: provide api for getting and setting slave info

Message ID 3aa6d0c8c471e0ca03be33ec725efa4db9758c04.1496256804.git.joseph.salisbury@canonical.com
State New
Headers show

Commit Message

Joseph Salisbury June 2, 2017, 3:19 p.m. UTC 
From: Jiri Pirko <jiri@resnulli.us>

BugLink: http://bugs.launchpad.net/bugs/1690094

Recent patch
bonding: add netlink attributes to slave link dev (1d3ee88ae0d6)

Introduced yet another device specific way to access slave information
over rtnetlink. There is one already there for bridge.

This patch introduces generic way to do this, for getting and setting
info as well by extending link_ops. Later on, this new interface will
be used for bridge ports as well.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
(backported from commit ba7d49b1f0f8e5f24294a880ed576964059af5ef)
Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
---
 include/net/rtnetlink.h      |  14 ++++
 include/uapi/linux/if_link.h |   2 +
 net/core/rtnetlink.c         | 155 ++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 154 insertions(+), 17 deletions(-)
diff mbox

Patch

diff --git a/include/net/rtnetlink.h b/include/net/rtnetlink.h
index bb13a18..59830f9 100644
--- a/include/net/rtnetlink.h
+++ b/include/net/rtnetlink.h
@@ -79,6 +79,20 @@  struct rtnl_link_ops {
 					       const struct net_device *dev);
 	unsigned int		(*get_num_tx_queues)(void);
 	unsigned int		(*get_num_rx_queues)(void);
+
+	int			slave_maxtype;
+	const struct nla_policy	*slave_policy;
+	int			(*slave_validate)(struct nlattr *tb[],
+						  struct nlattr *data[]);
+	int			(*slave_changelink)(struct net_device *dev,
+						    struct net_device *slave_dev,
+						    struct nlattr *tb[],
+						    struct nlattr *data[]);
+	size_t			(*get_slave_size)(const struct net_device *dev,
+						  const struct net_device *slave_dev);
+	int			(*fill_slave_info)(struct sk_buff *skb,
+						   const struct net_device *dev,
+						   const struct net_device *slave_dev);
 };
 
 int __rtnl_link_register(struct rtnl_link_ops *ops);
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 6db4601..8a6063a 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -240,6 +240,8 @@  enum {
 	IFLA_INFO_KIND,
 	IFLA_INFO_DATA,
 	IFLA_INFO_XSTATS,
+	IFLA_INFO_SLAVE_KIND,
+	IFLA_INFO_SLAVE_DATA,
 	__IFLA_INFO_MAX,
 };
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index ba9a9af..d8638b9 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -396,6 +396,22 @@  void rtnl_link_unregister(struct rtnl_link_ops *ops)
 }
 EXPORT_SYMBOL_GPL(rtnl_link_unregister);
 
+static size_t rtnl_link_get_slave_info_data_size(const struct net_device *dev)
+{
+	struct net_device *master_dev;
+	const struct rtnl_link_ops *ops;
+
+	master_dev = netdev_master_upper_dev_get((struct net_device *) dev);
+	if (!master_dev)
+		return 0;
+	ops = master_dev->rtnl_link_ops;
+	if (!ops->get_slave_size)
+		return 0;
+	/* IFLA_INFO_SLAVE_DATA + nested data */
+	return nla_total_size(sizeof(struct nlattr)) +
+	       ops->get_slave_size(master_dev, dev);
+}
+
 static size_t rtnl_link_get_size(const struct net_device *dev)
 {
 	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
@@ -416,6 +432,8 @@  static size_t rtnl_link_get_size(const struct net_device *dev)
 		/* IFLA_INFO_XSTATS */
 		size += nla_total_size(ops->get_xstats_size(dev));
 
+	size += rtnl_link_get_slave_info_data_size(dev);
+
 	return size;
 }
 
@@ -508,40 +526,101 @@  static size_t rtnl_link_get_af_size(const struct net_device *dev)
 	return size;
 }
 
-static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
+static bool rtnl_have_link_slave_info(const struct net_device *dev)
 {
-	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
-	struct nlattr *linkinfo, *data;
-	int err = -EMSGSIZE;
+	struct net_device *master_dev;
 
-	linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
-	if (linkinfo == NULL)
-		goto out;
+	master_dev = netdev_master_upper_dev_get((struct net_device *) dev);
+	if (master_dev && master_dev->rtnl_link_ops &&
+	    master_dev->rtnl_link_ops->fill_slave_info)
+		return true;
+	return false;
+}
+
+static int rtnl_link_slave_info_fill(struct sk_buff *skb,
+				     const struct net_device *dev)
+{
+	struct net_device *master_dev;
+	const struct rtnl_link_ops *ops;
+	struct nlattr *slave_data;
+	int err;
+
+	master_dev = netdev_master_upper_dev_get((struct net_device *) dev);
+	if (!master_dev)
+		return 0;
+	ops = master_dev->rtnl_link_ops;
+	if (!ops)
+		return 0;
+	if (nla_put_string(skb, IFLA_INFO_SLAVE_KIND, ops->kind) < 0)
+		return -EMSGSIZE;
+	if (ops->fill_slave_info) {
+		slave_data = nla_nest_start(skb, IFLA_INFO_SLAVE_DATA);
+		if (!slave_data)
+			return -EMSGSIZE;
+		err = ops->fill_slave_info(skb, master_dev, dev);
+		if (err < 0)
+			goto err_cancel_slave_data;
+		nla_nest_end(skb, slave_data);
+	}
+	return 0;
+
+err_cancel_slave_data:
+	nla_nest_cancel(skb, slave_data);
+	return err;
+}
 
+static int rtnl_link_info_fill(struct sk_buff *skb,
+			       const struct net_device *dev)
+{
+	const struct rtnl_link_ops *ops = dev->rtnl_link_ops;
+	struct nlattr *data;
+	int err;
+
+	if (!ops)
+		return 0;
 	if (nla_put_string(skb, IFLA_INFO_KIND, ops->kind) < 0)
-		goto err_cancel_link;
+		return -EMSGSIZE;
 	if (ops->fill_xstats) {
 		err = ops->fill_xstats(skb, dev);
 		if (err < 0)
-			goto err_cancel_link;
+			return err;
 	}
 	if (ops->fill_info) {
 		data = nla_nest_start(skb, IFLA_INFO_DATA);
-		if (data == NULL) {
-			err = -EMSGSIZE;
-			goto err_cancel_link;
-		}
+		if (data == NULL)
+			return -EMSGSIZE;
 		err = ops->fill_info(skb, dev);
 		if (err < 0)
 			goto err_cancel_data;
 		nla_nest_end(skb, data);
 	}
-
-	nla_nest_end(skb, linkinfo);
 	return 0;
 
 err_cancel_data:
 	nla_nest_cancel(skb, data);
+	return err;
+}
+
+static int rtnl_link_fill(struct sk_buff *skb, const struct net_device *dev)
+{
+	struct nlattr *linkinfo;
+	int err = -EMSGSIZE;
+
+	linkinfo = nla_nest_start(skb, IFLA_LINKINFO);
+	if (linkinfo == NULL)
+		goto out;
+
+	err = rtnl_link_info_fill(skb, dev);
+	if (err < 0)
+		goto err_cancel_link;
+
+	err = rtnl_link_slave_info_fill(skb, dev);
+	if (err < 0)
+		goto err_cancel_link;
+
+	nla_nest_end(skb, linkinfo);
+	return 0;
+
 err_cancel_link:
 	nla_nest_cancel(skb, linkinfo);
 out:
@@ -1057,7 +1136,7 @@  static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 	if (rtnl_port_fill(skb, dev, ext_filter_mask))
 		goto nla_put_failure;
 
-	if (dev->rtnl_link_ops) {
+	if (dev->rtnl_link_ops || rtnl_have_link_slave_info(dev)) {
 		if (rtnl_link_fill(skb, dev) < 0)
 			goto nla_put_failure;
 	}
@@ -1197,6 +1276,8 @@  EXPORT_SYMBOL(ifla_policy);
 static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {
 	[IFLA_INFO_KIND]	= { .type = NLA_STRING },
 	[IFLA_INFO_DATA]	= { .type = NLA_NESTED },
+	[IFLA_INFO_SLAVE_KIND]	= { .type = NLA_STRING },
+	[IFLA_INFO_SLAVE_DATA]	= { .type = NLA_NESTED },
 };
 
 static const struct nla_policy ifla_vf_policy[IFLA_VF_MAX+1] = {
@@ -1784,7 +1865,9 @@  static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh)
 {
 	struct net *net = sock_net(skb->sk);
 	const struct rtnl_link_ops *ops;
+	const struct rtnl_link_ops *m_ops = NULL;
 	struct net_device *dev;
+	struct net_device *master_dev = NULL;
 	struct ifinfomsg *ifm;
 	char kind[MODULE_NAME_LEN];
 	char ifname[IFNAMSIZ];
@@ -1814,6 +1897,12 @@  replay:
 			dev = NULL;
 	}
 
+	if (dev) {
+		master_dev = netdev_master_upper_dev_get(dev);
+		if (master_dev)
+			m_ops = master_dev->rtnl_link_ops;
+	}
+
 	err = validate_linkmsg(dev, tb);
 	if (err < 0)
 		return err;
@@ -1835,7 +1924,10 @@  replay:
 	}
 
 	if (1) {
-		struct nlattr *attr[ops ? ops->maxtype + 1 : 0], **data = NULL;
+		struct nlattr *attr[ops ? ops->maxtype + 1 : 0];
+		struct nlattr *slave_attr[m_ops ? m_ops->slave_maxtype + 1 : 0];
+		struct nlattr **data = NULL;
+		struct nlattr **slave_data = NULL;
 		struct net *dest_net;
 
 		if (ops) {
@@ -1854,6 +1946,24 @@  replay:
 			}
 		}
 
+		if (m_ops) {
+			if (m_ops->slave_maxtype &&
+			    linkinfo[IFLA_INFO_SLAVE_DATA]) {
+				err = nla_parse_nested(slave_attr,
+						       m_ops->slave_maxtype,
+						       linkinfo[IFLA_INFO_SLAVE_DATA],
+						       m_ops->slave_policy);
+				if (err < 0)
+					return err;
+				slave_data = slave_attr;
+			}
+			if (m_ops->slave_validate) {
+				err = m_ops->slave_validate(tb, slave_data);
+				if (err < 0)
+					return err;
+			}
+		}
+
 		if (dev) {
 			int modified = 0;
 
@@ -1873,6 +1983,17 @@  replay:
 				modified = 1;
 			}
 
+			if (linkinfo[IFLA_INFO_SLAVE_DATA]) {
+				if (!m_ops || !m_ops->slave_changelink)
+					return -EOPNOTSUPP;
+
+				err = m_ops->slave_changelink(master_dev, dev,
+							      tb, slave_data);
+				if (err < 0)
+					return err;
+				modified = 1;
+			}
+
 			return do_setlink(skb, dev, ifm, tb, ifname, modified);
 		}