[patch net-next V3 00/15] net: introduce upper device lists and remove dev->master

[patch net-next V3 00/15] net: introduce upper device lists and remove dev->master

[Jiri Pirko]

This is a V3 of a repost of my previous patchset:
"[patch net-next v2 00/15] net: introduce upper device lists and remove dev->master" fomr Aug 14

The discussion around
"[net-next] bonding: don't allow the master to become its slave"
forced me to think about upper<->lower device connections.

This patchset adds a possibility to record upper device linkage.
All upper<->lower devices are converted to use this mechanism right after.
That leads to dev->master removal because this info becomes redundant since
"master links" have the same value.

After all changes, there is no longer possible to do things as:
"bond->someotherdevice->samebond"

Also I think that drivers like cxgb3, qlcnic, qeth would benefit by this
in future by being able to get more appropriate info about l3 addresses.

v2->v3:
- removed recursion in __netdev_has_upper_dev()
- refreshed bits to be applicable on current net-next

v1->v2:
- s/unique/master/ better naming + stays closer to the past
- fixed vlan err goto
- original patch 15 (WARN_ON change) is squashed into the first patch

Jiri Pirko (15):
  net: introduce upper device lists
  macvlan: add link to upper device
  vlan: add link to upper device
  rtnetlink: remove usage of dev->master
  team: remove usage of netdev_set_master()
  bridge: remove usage of netdev_set_master()
  netpoll: remove usage of dev->master
  cxgb3: remove usage of dev->master
  qlcnic: guard __vlan_find_dev_deep() by rcu_read_lock
  qeth: ensure that __vlan_find_dev_deep() is called with rcu_read_lock
  vlan: remove usage of dev->master in __vlan_find_dev_deep()
  nes: remove usage of dev->master
  bonding: remove usage of dev->master
  net: remove no longer used netdev_set_bond_master() and
    netdev_set_master()
  net: kill dev->master

 drivers/infiniband/hw/nes/nes.c                    |   8 +-
 drivers/infiniband/hw/nes/nes_cm.c                 |   2 +-
 drivers/net/bonding/bond_3ad.c                     |  30 +--
 drivers/net/bonding/bond_alb.c                     |   6 +-
 drivers/net/bonding/bond_main.c                    |  94 +++++---
 drivers/net/bonding/bonding.h                      |  14 +-
 drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c |  11 +-
 drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c   |   2 +
 drivers/net/macvlan.c                              |   9 +-
 drivers/net/team/team.c                            |  13 +-
 drivers/s390/net/qeth_l3_main.c                    |  21 +-
 include/linux/netdevice.h                          |  22 +-
 net/8021q/vlan.c                                   |  10 +-
 net/8021q/vlan_core.c                              |  18 +-
 net/bridge/br_if.c                                 |   6 +-
 net/core/dev.c                                     | 262 ++++++++++++++++++---
 net/core/netpoll.c                                 |   9 +-
 net/core/rtnetlink.c                               |  70 +++---
 18 files changed, 425 insertions(+), 182 deletions(-)

-- 
1.8.0

[patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

This lists are supposed to serve for storing pointers to all upper devices.
Eventually it will replace dev->master pointer which is used for
bonding, bridge, team but it cannot be used for vlan, macvlan where
there might be multiple upper present. In case the upper link is
replacement for dev->master, it is marked with "master" flag.

New upper device list resolves this limitation. Also, the information
stored in lists is used for preventing looping setups like
"bond->somethingelse->samebond"

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 include/linux/netdevice.h |  14 +++
 net/core/dev.c            | 255 +++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 265 insertions(+), 4 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 0e1b92a..2e5a217 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1172,6 +1172,8 @@ struct net_device {
 					  * which this device is member of.
 					  */
 
+	struct list_head	upper_dev_list; /* List of upper devices */
+
 	/* Interface address info used in eth_type_trans() */
 	unsigned char		*dev_addr;	/* hw address, (before bcast
 						   because most packets are
@@ -2633,6 +2635,18 @@ extern int		netdev_max_backlog;
 extern int		netdev_tstamp_prequeue;
 extern int		weight_p;
 extern int		bpf_jit_enable;
+
+extern bool netdev_has_upper_dev(struct net_device *dev,
+				 struct net_device *upper_dev);
+extern bool netdev_has_any_upper_dev(struct net_device *dev);
+extern struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
+extern struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev);
+extern int netdev_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev);
+extern int netdev_master_upper_dev_link(struct net_device *dev,
+					struct net_device *upper_dev);
+extern void netdev_upper_dev_unlink(struct net_device *dev,
+				    struct net_device *upper_dev);
 extern int		netdev_set_master(struct net_device *dev, struct net_device *master);
 extern int netdev_set_bond_master(struct net_device *dev,
 				  struct net_device *master);
diff --git a/net/core/dev.c b/net/core/dev.c
index 21c5b97..cf63a85 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4600,6 +4600,248 @@ static int __init dev_proc_init(void)
 #endif	/* CONFIG_PROC_FS */
 
 
+struct netdev_upper {
+	struct net_device *dev;
+	bool master;
+	struct list_head list;
+	struct rcu_head rcu;
+	struct list_head search_list;
+};
+
+static void __append_search_uppers(struct list_head *search_list, struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	list_for_each_entry(upper, &dev->upper_dev_list, list) {
+		/* check if this upper is not already in search list */
+		if (list_empty(&upper->search_list))
+			list_add_tail(&upper->search_list, search_list);
+	}
+}
+
+static bool __netdev_has_upper_dev(struct net_device *dev,
+				   struct net_device *upper_dev)
+{
+	LIST_HEAD(search_list);
+	struct netdev_upper *upper;
+	struct netdev_upper *tmp;
+	bool ret = false;
+
+	__append_search_uppers(&search_list, dev);
+	list_for_each_entry(upper, &search_list, search_list) {
+		if (upper->dev == upper_dev) {
+			ret = true;
+			break;
+		}
+		__append_search_uppers(&search_list, upper->dev);
+	}
+	list_for_each_entry_safe(upper, tmp, &search_list, search_list)
+		INIT_LIST_HEAD(&upper->search_list);
+	return ret;
+}
+
+static struct netdev_upper *__netdev_find_upper(struct net_device *dev,
+						struct net_device *upper_dev)
+{
+	struct netdev_upper *upper;
+
+	list_for_each_entry(upper, &dev->upper_dev_list, list) {
+		if (upper->dev == upper_dev)
+			return upper;
+	}
+	return NULL;
+}
+
+/**
+ * netdev_has_upper_dev - Check if device is linked to an upper device
+ * @dev: device
+ * @upper_dev: upper device to check
+ *
+ * Find out if a device is linked to specified upper device and return true
+ * in case it is. The caller must hold the RTNL semaphore.
+ */
+bool netdev_has_upper_dev(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	ASSERT_RTNL();
+
+	return __netdev_find_upper(dev, upper_dev);
+}
+EXPORT_SYMBOL(netdev_has_upper_dev);
+
+/**
+ * netdev_has_any_upper_dev - Check if device is linked to some device
+ * @dev: device
+ *
+ * Find out if a device is linked to an upper device and return true in case
+ * it is. The caller must hold the RTNL semaphore.
+ */
+bool netdev_has_any_upper_dev(struct net_device *dev)
+{
+	ASSERT_RTNL();
+
+	return !list_empty(&dev->upper_dev_list);
+}
+EXPORT_SYMBOL(netdev_has_any_upper_dev);
+
+/**
+ * netdev_master_upper_dev_get - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RTNL semaphore.
+ */
+struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	if (list_empty(&dev->upper_dev_list))
+		return NULL;
+
+	upper = list_first_entry(&dev->upper_dev_list,
+				 struct netdev_upper, list);
+	if (likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get);
+
+/**
+ * netdev_master_upper_dev_get_rcu - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RCU read lock.
+ */
+struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	upper = list_first_or_null_rcu(&dev->upper_dev_list,
+				       struct netdev_upper, list);
+	if (upper && likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
+
+static int __netdev_upper_dev_link(struct net_device *dev,
+				   struct net_device *upper_dev, bool master)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	if (dev == upper_dev)
+		return -EBUSY;
+	/*
+	 * To prevent loops, check if dev is not upper device to upper_dev.
+	 */
+	if (__netdev_has_upper_dev(upper_dev, dev))
+		return -EBUSY;
+
+	if (__netdev_find_upper(dev, upper_dev))
+		return -EEXIST;
+
+	if (master && netdev_master_upper_dev_get(dev))
+		return -EBUSY;
+
+	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
+	if (!upper)
+		return -ENOMEM;
+
+	upper->dev = upper_dev;
+	upper->master = master;
+	INIT_LIST_HEAD(&upper->search_list);
+
+	/*
+	 * Ensure that master upper link is always the first item in the list.
+	 */
+	if (master)
+		list_add_rcu(&upper->list, &dev->upper_dev_list);
+	else
+		list_add_tail_rcu(&upper->list, &dev->upper_dev_list);
+	dev_hold(upper_dev);
+
+	return 0;
+}
+/**
+ * netdev_upper_dev_link - Add a link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. The caller must hold
+ * the RTNL semaphore. On a failure a negative errno code is returned.
+ * On success the reference counts are adjusted and the function
+ * returns zero.
+ */
+int netdev_upper_dev_link(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, false);
+}
+EXPORT_SYMBOL(netdev_upper_dev_link);
+
+/**
+ * netdev_master_upper_dev_link - Add a master link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. In this case, only
+ * one master upper device can be linked, although other non-master devices
+ * might be linked as well. The caller must hold the RTNL semaphore.
+ * On a failure a negative errno code is returned. On success the reference
+ * counts are adjusted and the function returns zero.
+ */
+int netdev_master_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, true);
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_link);
+
+/**
+ * netdev_upper_free_rcu - Frees a upper device list item via the RCU pointer
+ * @entry: the entry's RCU field
+ *
+ * This function is designed to be used as a callback to the call_rcu()
+ * function so that the memory allocated to the netdev upper device list item
+ * can be released safely.
+ */
+static void netdev_upper_free_rcu(struct rcu_head *entry)
+{
+	struct netdev_upper *upper;
+
+	upper = container_of(entry, struct netdev_upper, rcu);
+	kfree(upper);
+}
+
+/**
+ * netdev_upper_dev_unlink - Removes a link to upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Removes a link to device which is upper to this one. The caller must hold
+ * the RTNL semaphore.
+ */
+void netdev_upper_dev_unlink(struct net_device *dev,
+			     struct net_device *upper_dev)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	upper = __netdev_find_upper(dev, upper_dev);
+	if (!upper)
+		return;
+	list_del_rcu(&upper->list);
+	dev_put(upper_dev);
+	call_rcu(&upper->rcu, netdev_upper_free_rcu);
+}
+EXPORT_SYMBOL(netdev_upper_dev_unlink);
+
 /**
  *	netdev_set_master	-	set up master pointer
  *	@slave: slave device
@@ -4613,19 +4855,23 @@ static int __init dev_proc_init(void)
 int netdev_set_master(struct net_device *slave, struct net_device *master)
 {
 	struct net_device *old = slave->master;
+	int err;
 
 	ASSERT_RTNL();
 
 	if (master) {
 		if (old)
 			return -EBUSY;
-		dev_hold(master);
+		err = netdev_master_upper_dev_link(slave, master);
+		if (err)
+			return err;
 	}
 
 	slave->master = master;
 
 	if (old)
-		dev_put(old);
+		netdev_upper_dev_unlink(slave, master);
+
 	return 0;
 }
 EXPORT_SYMBOL(netdev_set_master);
@@ -5501,8 +5747,8 @@ static void rollback_registered_many(struct list_head *head)
 		if (dev->netdev_ops->ndo_uninit)
 			dev->netdev_ops->ndo_uninit(dev);
 
-		/* Notifier chain MUST detach us from master device. */
-		WARN_ON(dev->master);
+		/* Notifier chain MUST detach us all upper devices. */
+		WARN_ON(netdev_has_any_upper_dev(dev));
 
 		/* Remove entries from kobject tree */
 		netdev_unregister_kobject(dev);
@@ -6210,6 +6456,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 	INIT_LIST_HEAD(&dev->napi_list);
 	INIT_LIST_HEAD(&dev->unreg_list);
 	INIT_LIST_HEAD(&dev->link_watch_list);
+	INIT_LIST_HEAD(&dev->upper_dev_list);
 	dev->priv_flags = IFF_XMIT_DST_RELEASE;
 	setup(dev);
 
-- 
1.8.0

[patch net-next 02/15] macvlan: add link to upper device

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/net/macvlan.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 68a43fe..b7b614f 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -765,16 +765,22 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
 		memcpy(dev->dev_addr, lowerdev->dev_addr, ETH_ALEN);
 	}
 
+	err = netdev_upper_dev_link(lowerdev, dev);
+	if (err)
+		goto destroy_port;
+
 	port->count += 1;
 	err = register_netdevice(dev);
 	if (err < 0)
-		goto destroy_port;
+		goto upper_dev_unlink;
 
 	list_add_tail(&vlan->list, &port->vlans);
 	netif_stacked_transfer_operstate(lowerdev, dev);
 
 	return 0;
 
+upper_dev_unlink:
+	netdev_upper_dev_unlink(lowerdev, dev);
 destroy_port:
 	port->count -= 1;
 	if (!port->count)
@@ -798,6 +804,7 @@ void macvlan_dellink(struct net_device *dev, struct list_head *head)
 
 	list_del(&vlan->list);
 	unregister_netdevice_queue(dev, head);
+	netdev_upper_dev_unlink(vlan->lowerdev, dev);
 }
 EXPORT_SYMBOL_GPL(macvlan_dellink);
 
-- 
1.8.0

[patch net-next 03/15] vlan: add link to upper device

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/8021q/vlan.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/net/8021q/vlan.c b/net/8021q/vlan.c
index a292e80..babfde9 100644
--- a/net/8021q/vlan.c
+++ b/net/8021q/vlan.c
@@ -105,6 +105,8 @@ void unregister_vlan_dev(struct net_device *dev, struct list_head *head)
 	 */
 	unregister_netdevice_queue(dev, head);
 
+	netdev_upper_dev_unlink(real_dev, dev);
+
 	if (grp->nr_vlan_devs == 0)
 		vlan_gvrp_uninit_applicant(real_dev);
 
@@ -162,9 +164,13 @@ int register_vlan_dev(struct net_device *dev)
 	if (err < 0)
 		goto out_uninit_applicant;
 
+	err = netdev_upper_dev_link(real_dev, dev);
+	if (err)
+		goto out_uninit_applicant;
+
 	err = register_netdevice(dev);
 	if (err < 0)
-		goto out_uninit_applicant;
+		goto out_upper_dev_unlink;
 
 	/* Account for reference in struct vlan_dev_priv */
 	dev_hold(real_dev);
@@ -180,6 +186,8 @@ int register_vlan_dev(struct net_device *dev)
 
 	return 0;
 
+out_upper_dev_unlink:
+	netdev_upper_dev_unlink(real_dev, dev);
 out_uninit_applicant:
 	if (grp->nr_vlan_devs == 0)
 		vlan_gvrp_uninit_applicant(real_dev);
-- 
1.8.0

[patch net-next 04/15] rtnetlink: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/core/rtnetlink.c | 69 ++++++++++++++++++++++++++++------------------------
 1 file changed, 37 insertions(+), 32 deletions(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 2ef7a56..ae612f4 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -880,6 +880,7 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 	const struct rtnl_link_stats64 *stats;
 	struct nlattr *attr, *af_spec;
 	struct rtnl_af_ops *af_ops;
+	struct net_device *upper_dev = netdev_master_upper_dev_get(dev);
 
 	ASSERT_RTNL();
 	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
@@ -908,8 +909,8 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, struct net_device *dev,
 #endif
 	    (dev->ifindex != dev->iflink &&
 	     nla_put_u32(skb, IFLA_LINK, dev->iflink)) ||
-	    (dev->master &&
-	     nla_put_u32(skb, IFLA_MASTER, dev->master->ifindex)) ||
+	    (upper_dev &&
+	     nla_put_u32(skb, IFLA_MASTER, upper_dev->ifindex)) ||
 	    nla_put_u8(skb, IFLA_CARRIER, netif_carrier_ok(dev)) ||
 	    (dev->qdisc &&
 	     nla_put_string(skb, IFLA_QDISC, dev->qdisc->ops->id)) ||
@@ -1273,16 +1274,16 @@ static int do_setvfinfo(struct net_device *dev, struct nlattr *attr)
 
 static int do_set_master(struct net_device *dev, int ifindex)
 {
-	struct net_device *master_dev;
+	struct net_device *upper_dev = netdev_master_upper_dev_get(dev);
 	const struct net_device_ops *ops;
 	int err;
 
-	if (dev->master) {
-		if (dev->master->ifindex == ifindex)
+	if (upper_dev) {
+		if (upper_dev->ifindex == ifindex)
 			return 0;
-		ops = dev->master->netdev_ops;
+		ops = upper_dev->netdev_ops;
 		if (ops->ndo_del_slave) {
-			err = ops->ndo_del_slave(dev->master, dev);
+			err = ops->ndo_del_slave(upper_dev, dev);
 			if (err)
 				return err;
 		} else {
@@ -1291,12 +1292,12 @@ static int do_set_master(struct net_device *dev, int ifindex)
 	}
 
 	if (ifindex) {
-		master_dev = __dev_get_by_index(dev_net(dev), ifindex);
-		if (!master_dev)
+		upper_dev = __dev_get_by_index(dev_net(dev), ifindex);
+		if (!upper_dev)
 			return -EINVAL;
-		ops = master_dev->netdev_ops;
+		ops = upper_dev->netdev_ops;
 		if (ops->ndo_add_slave) {
-			err = ops->ndo_add_slave(master_dev, dev);
+			err = ops->ndo_add_slave(upper_dev, dev);
 			if (err)
 				return err;
 		} else {
@@ -2064,7 +2065,6 @@ errout:
 static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 {
 	struct net *net = sock_net(skb->sk);
-	struct net_device *master = NULL;
 	struct ndmsg *ndm;
 	struct nlattr *tb[NDA_MAX+1];
 	struct net_device *dev;
@@ -2106,10 +2106,10 @@ static int rtnl_fdb_add(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	/* Support fdb on master device the net/bridge default case */
 	if ((!ndm->ndm_flags || ndm->ndm_flags & NTF_MASTER) &&
 	    (dev->priv_flags & IFF_BRIDGE_PORT)) {
-		master = dev->master;
-		err = master->netdev_ops->ndo_fdb_add(ndm, tb,
-						      dev, addr,
-						      nlh->nlmsg_flags);
+		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
+		const struct net_device_ops *ops = br_dev->netdev_ops;
+
+		err = ops->ndo_fdb_add(ndm, tb, dev, addr, nlh->nlmsg_flags);
 		if (err)
 			goto out;
 		else
@@ -2170,10 +2170,11 @@ static int rtnl_fdb_del(struct sk_buff *skb, struct nlmsghdr *nlh, void *arg)
 	/* Support fdb on master device the net/bridge default case */
 	if ((!ndm->ndm_flags || ndm->ndm_flags & NTF_MASTER) &&
 	    (dev->priv_flags & IFF_BRIDGE_PORT)) {
-		struct net_device *master = dev->master;
+		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
+		const struct net_device_ops *ops = br_dev->netdev_ops;
 
-		if (master->netdev_ops->ndo_fdb_del)
-			err = master->netdev_ops->ndo_fdb_del(ndm, dev, addr);
+		if (ops->ndo_fdb_del)
+			err = ops->ndo_fdb_del(ndm, dev, addr);
 
 		if (err)
 			goto out;
@@ -2257,9 +2258,11 @@ static int rtnl_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb)
 	rcu_read_lock();
 	for_each_netdev_rcu(net, dev) {
 		if (dev->priv_flags & IFF_BRIDGE_PORT) {
-			struct net_device *master = dev->master;
-			const struct net_device_ops *ops = master->netdev_ops;
+			struct net_device *br_dev;
+			const struct net_device_ops *ops;
 
+			br_dev = netdev_master_upper_dev_get(dev);
+			ops = br_dev->netdev_ops;
 			if (ops->ndo_fdb_dump)
 				idx = ops->ndo_fdb_dump(skb, cb, dev, idx);
 		}
@@ -2280,6 +2283,7 @@ int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
 	struct ifinfomsg *ifm;
 	struct nlattr *br_afspec;
 	u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;
+	struct net_device *br_dev = netdev_master_upper_dev_get(dev);
 
 	nlh = nlmsg_put(skb, pid, seq, RTM_NEWLINK, sizeof(*ifm), NLM_F_MULTI);
 	if (nlh == NULL)
@@ -2297,8 +2301,8 @@ int ndo_dflt_bridge_getlink(struct sk_buff *skb, u32 pid, u32 seq,
 	if (nla_put_string(skb, IFLA_IFNAME, dev->name) ||
 	    nla_put_u32(skb, IFLA_MTU, dev->mtu) ||
 	    nla_put_u8(skb, IFLA_OPERSTATE, operstate) ||
-	    (dev->master &&
-	     nla_put_u32(skb, IFLA_MASTER, dev->master->ifindex)) ||
+	    (br_dev &&
+	     nla_put_u32(skb, IFLA_MASTER, br_dev->ifindex)) ||
 	    (dev->addr_len &&
 	     nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) ||
 	    (dev->ifindex != dev->iflink &&
@@ -2334,11 +2338,11 @@ static int rtnl_bridge_getlink(struct sk_buff *skb, struct netlink_callback *cb)
 	rcu_read_lock();
 	for_each_netdev_rcu(net, dev) {
 		const struct net_device_ops *ops = dev->netdev_ops;
-		struct net_device *master = dev->master;
+		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
 
-		if (master && master->netdev_ops->ndo_bridge_getlink) {
+		if (br_dev && br_dev->netdev_ops->ndo_bridge_getlink) {
 			if (idx >= cb->args[0] &&
-			    master->netdev_ops->ndo_bridge_getlink(
+			    br_dev->netdev_ops->ndo_bridge_getlink(
 				    skb, portid, seq, dev) < 0)
 				break;
 			idx++;
@@ -2375,7 +2379,7 @@ static inline size_t bridge_nlmsg_size(void)
 static int rtnl_bridge_notify(struct net_device *dev, u16 flags)
 {
 	struct net *net = dev_net(dev);
-	struct net_device *master = dev->master;
+	struct net_device *br_dev = netdev_master_upper_dev_get(dev);
 	struct sk_buff *skb;
 	int err = -EOPNOTSUPP;
 
@@ -2386,8 +2390,8 @@ static int rtnl_bridge_notify(struct net_device *dev, u16 flags)
 	}
 
 	if ((!flags || (flags & BRIDGE_FLAGS_MASTER)) &&
-	    master && master->netdev_ops->ndo_bridge_getlink) {
-		err = master->netdev_ops->ndo_bridge_getlink(skb, 0, 0, dev);
+	    br_dev && br_dev->netdev_ops->ndo_bridge_getlink) {
+		err = br_dev->netdev_ops->ndo_bridge_getlink(skb, 0, 0, dev);
 		if (err < 0)
 			goto errout;
 	}
@@ -2446,13 +2450,14 @@ static int rtnl_bridge_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 	oflags = flags;
 
 	if (!flags || (flags & BRIDGE_FLAGS_MASTER)) {
-		if (!dev->master ||
-		    !dev->master->netdev_ops->ndo_bridge_setlink) {
+		struct net_device *br_dev = netdev_master_upper_dev_get(dev);
+
+		if (!br_dev || !br_dev->netdev_ops->ndo_bridge_setlink) {
 			err = -EOPNOTSUPP;
 			goto out;
 		}
 
-		err = dev->master->netdev_ops->ndo_bridge_setlink(dev, nlh);
+		err = br_dev->netdev_ops->ndo_bridge_setlink(dev, nlh);
 		if (err)
 			goto out;
 
-- 
1.8.0

[patch net-next 05/15] team: remove usage of netdev_set_master()

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/net/team/team.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c
index ad86660..c19c74e 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1054,10 +1054,11 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
 		}
 	}
 
-	err = netdev_set_master(port_dev, dev);
+	err = netdev_master_upper_dev_link(port_dev, dev);
 	if (err) {
-		netdev_err(dev, "Device %s failed to set master\n", portname);
-		goto err_set_master;
+		netdev_err(dev, "Device %s failed to set upper link\n",
+			   portname);
+		goto err_set_upper_link;
 	}
 
 	err = netdev_rx_handler_register(port_dev, team_handle_frame,
@@ -1090,9 +1091,9 @@ err_option_port_add:
 	netdev_rx_handler_unregister(port_dev);
 
 err_handler_register:
-	netdev_set_master(port_dev, NULL);
+	netdev_upper_dev_unlink(port_dev, dev);
 
-err_set_master:
+err_set_upper_link:
 	team_port_disable_netpoll(port);
 
 err_enable_netpoll:
@@ -1136,7 +1137,7 @@ static int team_port_del(struct team *team, struct net_device *port_dev)
 	team_port_disable(team, port);
 	list_del_rcu(&port->list);
 	netdev_rx_handler_unregister(port_dev);
-	netdev_set_master(port_dev, NULL);
+	netdev_upper_dev_unlink(port_dev, dev);
 	team_port_disable_netpoll(port);
 	vlan_vids_del_by_dev(port_dev, dev);
 	dev_close(port_dev);
-- 
1.8.0

[patch net-next 06/15] bridge: remove usage of netdev_set_master()

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/bridge/br_if.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 37fe693..742e467 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -148,7 +148,7 @@ static void del_nbp(struct net_bridge_port *p)
 	netdev_rx_handler_unregister(dev);
 	synchronize_net();
 
-	netdev_set_master(dev, NULL);
+	netdev_upper_dev_unlink(dev, br->dev);
 
 	br_multicast_del_port(p);
 
@@ -364,7 +364,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
 	if (br_netpoll_info(br) && ((err = br_netpoll_enable(p, GFP_KERNEL))))
 		goto err3;
 
-	err = netdev_set_master(dev, br->dev);
+	err = netdev_master_upper_dev_link(dev, br->dev);
 	if (err)
 		goto err4;
 
@@ -403,7 +403,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
 	return 0;
 
 err5:
-	netdev_set_master(dev, NULL);
+	netdev_upper_dev_unlink(dev, br->dev);
 err4:
 	br_netpoll_disable(p);
 err3:
-- 
1.8.0

[patch net-next 07/15] netpoll: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/core/netpoll.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index 3151acf..d2bda8e 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -210,9 +210,12 @@ static void netpoll_poll_dev(struct net_device *dev)
 
 	if (dev->flags & IFF_SLAVE) {
 		if (ni) {
-			struct net_device *bond_dev = dev->master;
+			struct net_device *bond_dev;
 			struct sk_buff *skb;
-			struct netpoll_info *bond_ni = rcu_dereference_bh(bond_dev->npinfo);
+			struct netpoll_info *bond_ni;
+
+			bond_dev = netdev_master_upper_dev_get_rcu(dev);
+			bond_ni = rcu_dereference_bh(bond_dev->npinfo);
 			while ((skb = skb_dequeue(&ni->arp_tx))) {
 				skb->dev = bond_dev;
 				skb_queue_tail(&bond_ni->arp_tx, skb);
@@ -815,7 +818,7 @@ int netpoll_setup(struct netpoll *np)
 		return -ENODEV;
 	}
 
-	if (ndev->master) {
+	if (netdev_master_upper_dev_get(ndev)) {
 		np_err(np, "%s is a slave device, aborting\n", np->dev_name);
 		err = -EBUSY;
 		goto put;
-- 
1.8.0

[patch net-next 08/15] cxgb3: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
index 942dace..3f1f501 100644
--- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
+++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c
@@ -182,14 +182,17 @@ static struct net_device *get_iff_from_mac(struct adapter *adapter,
 		struct net_device *dev = adapter->port[i];
 
 		if (!memcmp(dev->dev_addr, mac, ETH_ALEN)) {
+			rcu_read_lock();
 			if (vlan && vlan != VLAN_VID_MASK) {
-				rcu_read_lock();
 				dev = __vlan_find_dev_deep(dev, vlan);
-				rcu_read_unlock();
 			} else if (netif_is_bond_slave(dev)) {
-				while (dev->master)
-					dev = dev->master;
+				struct net_device *upper_dev;
+
+				while ((upper_dev =
+					netdev_master_upper_dev_get_rcu(dev)))
+					dev = upper_dev;
 			}
+			rcu_read_unlock();
 			return dev;
 		}
 	}
-- 
1.8.0

[patch net-next 09/15] qlcnic: guard __vlan_find_dev_deep() by rcu_read_lock

[Jiri Pirko]

rcu_read_lock was missing here

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
index d833f59..95b628f 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -2867,12 +2867,14 @@ qlcnic_restore_indev_addr(struct net_device *netdev, unsigned long event)
 
 	qlcnic_config_indev_addr(adapter, netdev, event);
 
+	rcu_read_lock();
 	for_each_set_bit(vid, adapter->vlans, VLAN_N_VID) {
 		dev = __vlan_find_dev_deep(netdev, vid);
 		if (!dev)
 			continue;
 		qlcnic_config_indev_addr(adapter, dev, event);
 	}
+	rcu_read_unlock();
 }
 
 static int qlcnic_netdev_event(struct notifier_block *this,
-- 
1.8.0

[patch net-next 10/15] qeth: ensure that __vlan_find_dev_deep() is called with rcu_read_lock

[Jiri Pirko]

Also benefit from rcu_read_lock held and use __in_dev_get_rcu() in ipv4 case.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/s390/net/qeth_l3_main.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/s390/net/qeth_l3_main.c b/drivers/s390/net/qeth_l3_main.c
index 6e5eef0..0749efe 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1640,6 +1640,7 @@ static void qeth_l3_add_mc(struct qeth_card *card, struct in_device *in4_dev)
 	}
 }
 
+/* called with rcu_read_lock */
 static void qeth_l3_add_vlan_mc(struct qeth_card *card)
 {
 	struct in_device *in_dev;
@@ -1652,19 +1653,14 @@ static void qeth_l3_add_vlan_mc(struct qeth_card *card)
 	for_each_set_bit(vid, card->active_vlans, VLAN_N_VID) {
 		struct net_device *netdev;
 
-		rcu_read_lock();
 		netdev = __vlan_find_dev_deep(card->dev, vid);
-		rcu_read_unlock();
 		if (netdev == NULL ||
 		    !(netdev->flags & IFF_UP))
 			continue;
-		in_dev = in_dev_get(netdev);
+		in_dev = __in_dev_get_rcu(netdev);
 		if (!in_dev)
 			continue;
-		rcu_read_lock();
 		qeth_l3_add_mc(card, in_dev);
-		rcu_read_unlock();
-		in_dev_put(in_dev);
 	}
 }
 
@@ -1673,14 +1669,14 @@ static void qeth_l3_add_multicast_ipv4(struct qeth_card *card)
 	struct in_device *in4_dev;
 
 	QETH_CARD_TEXT(card, 4, "chkmcv4");
-	in4_dev = in_dev_get(card->dev);
-	if (in4_dev == NULL)
-		return;
 	rcu_read_lock();
+	in4_dev = __in_dev_get_rcu(card->dev);
+	if (in4_dev == NULL)
+		goto unlock;
 	qeth_l3_add_mc(card, in4_dev);
 	qeth_l3_add_vlan_mc(card);
+unlock:
 	rcu_read_unlock();
-	in_dev_put(in4_dev);
 }
 
 #ifdef CONFIG_QETH_IPV6
@@ -1705,6 +1701,7 @@ static void qeth_l3_add_mc6(struct qeth_card *card, struct inet6_dev *in6_dev)
 	}
 }
 
+/* called with rcu_read_lock */
 static void qeth_l3_add_vlan_mc6(struct qeth_card *card)
 {
 	struct inet6_dev *in_dev;
@@ -1741,10 +1738,12 @@ static void qeth_l3_add_multicast_ipv6(struct qeth_card *card)
 	in6_dev = in6_dev_get(card->dev);
 	if (in6_dev == NULL)
 		return;
+	rcu_read_lock();
 	read_lock_bh(&in6_dev->lock);
 	qeth_l3_add_mc6(card, in6_dev);
 	qeth_l3_add_vlan_mc6(card);
 	read_unlock_bh(&in6_dev->lock);
+	rcu_read_unlock();
 	in6_dev_put(in6_dev);
 }
 #endif /* CONFIG_QETH_IPV6 */
@@ -1813,8 +1812,10 @@ static void qeth_l3_free_vlan_addresses6(struct qeth_card *card,
 static void qeth_l3_free_vlan_addresses(struct qeth_card *card,
 			unsigned short vid)
 {
+	rcu_read_lock();
 	qeth_l3_free_vlan_addresses4(card, vid);
 	qeth_l3_free_vlan_addresses6(card, vid);
+	rcu_read_unlock();
 }
 
 static int qeth_l3_vlan_rx_add_vid(struct net_device *dev, unsigned short vid)
-- 
1.8.0

[patch net-next 11/15] vlan: remove usage of dev->master in __vlan_find_dev_deep()

[Jiri Pirko]

Also, since all users call __vlan_find_dev_deep() with rcu_read_lock,
make no possibility to call this with rtnl mutex held only.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/8021q/vlan_core.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/net/8021q/vlan_core.c b/net/8021q/vlan_core.c
index 65e06ab..380440b 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -60,21 +60,25 @@ bool vlan_do_receive(struct sk_buff **skbp)
 	return true;
 }
 
-/* Must be invoked with rcu_read_lock or with RTNL. */
-struct net_device *__vlan_find_dev_deep(struct net_device *real_dev,
+/* Must be invoked with rcu_read_lock. */
+struct net_device *__vlan_find_dev_deep(struct net_device *dev,
 					u16 vlan_id)
 {
-	struct vlan_info *vlan_info = rcu_dereference_rtnl(real_dev->vlan_info);
+	struct vlan_info *vlan_info = rcu_dereference(dev->vlan_info);
 
 	if (vlan_info) {
 		return vlan_group_get_device(&vlan_info->grp, vlan_id);
 	} else {
 		/*
-		 * Bonding slaves do not have grp assigned to themselves.
-		 * Grp is assigned to bonding master instead.
+		 * Lower devices of master uppers (bonding, team) do not have
+		 * grp assigned to themselves. Grp is assigned to upper device
+		 * instead.
 		 */
-		if (netif_is_bond_slave(real_dev))
-			return __vlan_find_dev_deep(real_dev->master, vlan_id);
+		struct net_device *upper_dev;
+
+		upper_dev = netdev_master_upper_dev_get_rcu(dev);
+		if (upper_dev)
+			return __vlan_find_dev_deep(upper_dev, vlan_id);
 	}
 
 	return NULL;
-- 
1.8.0

[patch net-next 12/15] nes: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/infiniband/hw/nes/nes.c    | 8 +++++---
 drivers/infiniband/hw/nes/nes_cm.c | 2 +-
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/infiniband/hw/nes/nes.c b/drivers/infiniband/hw/nes/nes.c
index 748db2d..d129c36 100644
--- a/drivers/infiniband/hw/nes/nes.c
+++ b/drivers/infiniband/hw/nes/nes.c
@@ -135,6 +135,7 @@ static int nes_inetaddr_event(struct notifier_block *notifier,
 	struct net_device *event_netdev = ifa->ifa_dev->dev;
 	struct nes_device *nesdev;
 	struct net_device *netdev;
+	struct net_device *upper_dev;
 	struct nes_vnic *nesvnic;
 	unsigned int is_bonded;
 
@@ -145,8 +146,9 @@ static int nes_inetaddr_event(struct notifier_block *notifier,
 				nesdev, nesdev->netdev[0]->name);
 		netdev = nesdev->netdev[0];
 		nesvnic = netdev_priv(netdev);
+		upper_dev = netdev_master_upper_dev_get(netdev);
 		is_bonded = netif_is_bond_slave(netdev) &&
-			    (netdev->master == event_netdev);
+			    (upper_dev == event_netdev);
 		if ((netdev == event_netdev) || is_bonded) {
 			if (nesvnic->rdma_enabled == 0) {
 				nes_debug(NES_DBG_NETDEV, "Returning without processing event for %s since"
@@ -179,9 +181,9 @@ static int nes_inetaddr_event(struct notifier_block *notifier,
 					/* fall through */
 				case NETDEV_CHANGEADDR:
 					/* Add the address to the IP table */
-					if (netdev->master)
+					if (upper_dev)
 						nesvnic->local_ipaddr =
-							((struct in_device *)netdev->master->ip_ptr)->ifa_list->ifa_address;
+							((struct in_device *)upper_dev->ip_ptr)->ifa_list->ifa_address;
 					else
 						nesvnic->local_ipaddr = ifa->ifa_address;
 
diff --git a/drivers/infiniband/hw/nes/nes_cm.c b/drivers/infiniband/hw/nes/nes_cm.c
index 22ea67e..ca6fbae 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1340,7 +1340,7 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip, int arpi
 	}
 
 	if (netif_is_bond_slave(nesvnic->netdev))
-		netdev = nesvnic->netdev->master;
+		netdev = netdev_unique_upper_dev_get(nesvnic->netdev);
 	else
 		netdev = nesvnic->netdev;
 
-- 
1.8.0

[patch net-next 13/15] bonding: remove usage of dev->master

[Jiri Pirko]

Benefit from new upper dev list and free bonding from dev->master usage.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 drivers/net/bonding/bond_3ad.c  | 30 ++++++-------
 drivers/net/bonding/bond_alb.c  |  6 +--
 drivers/net/bonding/bond_main.c | 94 ++++++++++++++++++++++++-----------------
 drivers/net/bonding/bonding.h   | 14 +++---
 net/core/rtnetlink.c            |  1 +
 5 files changed, 81 insertions(+), 64 deletions(-)

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index a030e63..84fabd6 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -1127,7 +1127,7 @@ static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port)
 				// INFO_RECEIVED_LOOPBACK_FRAMES
 				pr_err("%s: An illegal loopback occurred on adapter (%s).\n"
 				       "Check the configuration to verify that all adapters are connected to 802.3ad compliant switch ports\n",
-				       port->slave->dev->master->name, port->slave->dev->name);
+				       port->slave->bond->dev->name, port->slave->dev->name);
 				return;
 			}
 			__update_selected(lacpdu, port);
@@ -1306,7 +1306,7 @@ static void ad_port_selection_logic(struct port *port)
 		}
 		if (!curr_port) { // meaning: the port was related to an aggregator but was not on the aggregator port list
 			pr_warning("%s: Warning: Port %d (on %s) was related to aggregator %d but was not on its port list\n",
-				   port->slave->dev->master->name,
+				   port->slave->bond->dev->name,
 				   port->actor_port_number,
 				   port->slave->dev->name,
 				   port->aggregator->aggregator_identifier);
@@ -1386,7 +1386,7 @@ static void ad_port_selection_logic(struct port *port)
 				 port->aggregator->aggregator_identifier);
 		} else {
 			pr_err("%s: Port %d (on %s) did not find a suitable aggregator\n",
-			       port->slave->dev->master->name,
+			       port->slave->bond->dev->name,
 			       port->actor_port_number, port->slave->dev->name);
 		}
 	}
@@ -1463,7 +1463,7 @@ static struct aggregator *ad_agg_selection_test(struct aggregator *best,
 
 	default:
 		pr_warning("%s: Impossible agg select mode %d\n",
-			   curr->slave->dev->master->name,
+			   curr->slave->bond->dev->name,
 			   __get_agg_selection_mode(curr->lag_ports));
 		break;
 	}
@@ -1571,7 +1571,7 @@ static void ad_agg_selection_logic(struct aggregator *agg)
 		// check if any partner replys
 		if (best->is_individual) {
 			pr_warning("%s: Warning: No 802.3ad response from the link partner for any adapters in the bond\n",
-				   best->slave ? best->slave->dev->master->name : "NULL");
+				   best->slave ? best->slave->bond->dev->name : "NULL");
 		}
 
 		best->is_active = 1;
@@ -1898,7 +1898,7 @@ int bond_3ad_bind_slave(struct slave *slave)
 
 	if (bond == NULL) {
 		pr_err("%s: The slave %s is not attached to its bond\n",
-		       slave->dev->master->name, slave->dev->name);
+		       slave->bond->dev->name, slave->dev->name);
 		return -1;
 	}
 
@@ -1973,7 +1973,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
 	// if slave is null, the whole port is not initialized
 	if (!port->slave) {
 		pr_warning("Warning: %s: Trying to unbind an uninitialized port on %s\n",
-			   slave->dev->master->name, slave->dev->name);
+			   slave->bond->dev->name, slave->dev->name);
 		return;
 	}
 
@@ -2009,7 +2009,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
 
 				if ((new_aggregator->lag_ports == port) && new_aggregator->is_active) {
 					pr_info("%s: Removing an active aggregator\n",
-						aggregator->slave->dev->master->name);
+						aggregator->slave->bond->dev->name);
 					// select new active aggregator
 					 select_new_active_agg = 1;
 				}
@@ -2040,7 +2040,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
 					ad_agg_selection_logic(__get_first_agg(port));
 			} else {
 				pr_warning("%s: Warning: unbinding aggregator, and could not find a new aggregator for its ports\n",
-					   slave->dev->master->name);
+					   slave->bond->dev->name);
 			}
 		} else { // in case that the only port related to this aggregator is the one we want to remove
 			select_new_active_agg = aggregator->is_active;
@@ -2048,7 +2048,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
 			ad_clear_agg(aggregator);
 			if (select_new_active_agg) {
 				pr_info("%s: Removing an active aggregator\n",
-					slave->dev->master->name);
+					slave->bond->dev->name);
 				// select new active aggregator
 				ad_agg_selection_logic(__get_first_agg(port));
 			}
@@ -2076,7 +2076,7 @@ void bond_3ad_unbind_slave(struct slave *slave)
 					ad_clear_agg(temp_aggregator);
 					if (select_new_active_agg) {
 						pr_info("%s: Removing an active aggregator\n",
-							slave->dev->master->name);
+							slave->bond->dev->name);
 						// select new active aggregator
 						ad_agg_selection_logic(__get_first_agg(port));
 					}
@@ -2184,7 +2184,7 @@ static int bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave, u1
 
 		if (!port->slave) {
 			pr_warning("%s: Warning: port of slave %s is uninitialized\n",
-				   slave->dev->name, slave->dev->master->name);
+				   slave->dev->name, slave->bond->dev->name);
 			return ret;
 		}
 
@@ -2240,7 +2240,7 @@ void bond_3ad_adapter_speed_changed(struct slave *slave)
 	// if slave is null, the whole port is not initialized
 	if (!port->slave) {
 		pr_warning("Warning: %s: speed changed for uninitialized port on %s\n",
-			   slave->dev->master->name, slave->dev->name);
+			   slave->bond->dev->name, slave->dev->name);
 		return;
 	}
 
@@ -2268,7 +2268,7 @@ void bond_3ad_adapter_duplex_changed(struct slave *slave)
 	// if slave is null, the whole port is not initialized
 	if (!port->slave) {
 		pr_warning("%s: Warning: duplex changed for uninitialized port on %s\n",
-			   slave->dev->master->name, slave->dev->name);
+			   slave->bond->dev->name, slave->dev->name);
 		return;
 	}
 
@@ -2297,7 +2297,7 @@ void bond_3ad_handle_link_change(struct slave *slave, char link)
 	// if slave is null, the whole port is not initialized
 	if (!port->slave) {
 		pr_warning("Warning: %s: link status changed for uninitialized port on %s\n",
-			   slave->dev->master->name, slave->dev->name);
+			   slave->bond->dev->name, slave->dev->name);
 		return;
 	}
 
diff --git a/drivers/net/bonding/bond_alb.c b/drivers/net/bonding/bond_alb.c
index 7c9d136..f5e0527 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -507,7 +507,7 @@ static void rlb_update_client(struct rlb_client_info *client_info)
 				 client_info->mac_dst);
 		if (!skb) {
 			pr_err("%s: Error: failed to create an ARP packet\n",
-			       client_info->slave->dev->master->name);
+			       client_info->slave->bond->dev->name);
 			continue;
 		}
 
@@ -517,7 +517,7 @@ static void rlb_update_client(struct rlb_client_info *client_info)
 			skb = vlan_put_tag(skb, client_info->vlan_id);
 			if (!skb) {
 				pr_err("%s: Error: failed to insert VLAN tag\n",
-				       client_info->slave->dev->master->name);
+				       client_info->slave->bond->dev->name);
 				continue;
 			}
 		}
@@ -1043,7 +1043,7 @@ static int alb_set_slave_mac_addr(struct slave *slave, u8 addr[])
 	if (dev_set_mac_address(dev, &s_addr)) {
 		pr_err("%s: Error: dev_set_mac_address of dev %s failed!\n"
 		       "ALB mode requires that the base driver support setting the hw address also when the network device's interface is open\n",
-		       dev->master->name, dev->name);
+		       slave->bond->dev->name, dev->name);
 		return -EOPNOTSUPP;
 	}
 	return 0;
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index b7d45f3..c495298 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -746,11 +746,9 @@ static void __bond_resend_igmp_join_requests(struct net_device *dev)
 {
 	struct in_device *in_dev;
 
-	rcu_read_lock();
 	in_dev = __in_dev_get_rcu(dev);
 	if (in_dev)
 		ip_mc_rejoin_groups(in_dev);
-	rcu_read_unlock();
 }
 
 /*
@@ -760,9 +758,10 @@ static void __bond_resend_igmp_join_requests(struct net_device *dev)
  */
 static void bond_resend_igmp_join_requests(struct bonding *bond)
 {
-	struct net_device *bond_dev, *vlan_dev, *master_dev;
+	struct net_device *bond_dev, *vlan_dev, *upper_dev;
 	struct vlan_entry *vlan;
 
+	rcu_read_lock();
 	read_lock(&bond->lock);
 
 	bond_dev = bond->dev;
@@ -774,18 +773,14 @@ static void bond_resend_igmp_join_requests(struct bonding *bond)
 	 * if bond is enslaved to a bridge,
 	 * then rejoin all groups on its master
 	 */
-	master_dev = bond_dev->master;
-	if (master_dev)
-		if ((master_dev->priv_flags & IFF_EBRIDGE)
-			&& (bond_dev->priv_flags & IFF_BRIDGE_PORT))
-			__bond_resend_igmp_join_requests(master_dev);
+	upper_dev = netdev_master_upper_dev_get_rcu(bond_dev);
+	if (upper_dev && upper_dev->priv_flags & IFF_EBRIDGE)
+		__bond_resend_igmp_join_requests(upper_dev);
 
 	/* rejoin all groups on vlan devices */
 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
-		rcu_read_lock();
 		vlan_dev = __vlan_find_dev_deep(bond_dev,
 						vlan->vlan_id);
-		rcu_read_unlock();
 		if (vlan_dev)
 			__bond_resend_igmp_join_requests(vlan_dev);
 	}
@@ -794,13 +789,16 @@ static void bond_resend_igmp_join_requests(struct bonding *bond)
 		queue_delayed_work(bond->wq, &bond->mcast_work, HZ/5);
 
 	read_unlock(&bond->lock);
+	rcu_read_unlock();
 }
 
 static void bond_resend_igmp_join_requests_delayed(struct work_struct *work)
 {
 	struct bonding *bond = container_of(work, struct bonding,
 					    mcast_work.work);
+	rcu_read_lock();
 	bond_resend_igmp_join_requests(bond);
+	rcu_read_unlock();
 }
 
 /*
@@ -1493,6 +1491,27 @@ static rx_handler_result_t bond_handle_frame(struct sk_buff **pskb)
 	return ret;
 }
 
+static int bond_master_upper_dev_link(struct net_device *bond_dev,
+				      struct net_device *slave_dev)
+{
+	int err;
+
+	err = netdev_master_upper_dev_link(slave_dev, bond_dev);
+	if (err)
+		return err;
+	slave_dev->flags |= IFF_SLAVE;
+	rtmsg_ifinfo(RTM_NEWLINK, slave_dev, IFF_SLAVE);
+	return 0;
+}
+
+static void bond_upper_dev_unlink(struct net_device *bond_dev,
+				  struct net_device *slave_dev)
+{
+	netdev_upper_dev_unlink(slave_dev, bond_dev);
+	slave_dev->flags &= ~IFF_SLAVE;
+	rtmsg_ifinfo(RTM_NEWLINK, slave_dev, IFF_SLAVE);
+}
+
 /* enslave device <slave> to bond device <master> */
 int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 {
@@ -1655,9 +1674,9 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
 		}
 	}
 
-	res = netdev_set_bond_master(slave_dev, bond_dev);
+	res = bond_master_upper_dev_link(bond_dev, slave_dev);
 	if (res) {
-		pr_debug("Error %d calling netdev_set_bond_master\n", res);
+		pr_debug("Error %d calling bond_master_upper_dev_link\n", res);
 		goto err_restore_mac;
 	}
 
@@ -1891,7 +1910,7 @@ err_close:
 	dev_close(slave_dev);
 
 err_unset_master:
-	netdev_set_bond_master(slave_dev, NULL);
+	bond_upper_dev_unlink(bond_dev, slave_dev);
 
 err_restore_mac:
 	if (!bond->params.fail_over_mac) {
@@ -1936,7 +1955,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
 
 	/* slave is not a slave or master is not master of this slave */
 	if (!(slave_dev->flags & IFF_SLAVE) ||
-	    (slave_dev->master != bond_dev)) {
+	    !netdev_has_upper_dev(slave_dev, bond_dev)) {
 		pr_err("%s: Error: cannot release %s.\n",
 		       bond_dev->name, slave_dev->name);
 		return -EINVAL;
@@ -2080,7 +2099,7 @@ int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
 		netif_addr_unlock_bh(bond_dev);
 	}
 
-	netdev_set_bond_master(slave_dev, NULL);
+	bond_upper_dev_unlink(bond_dev, slave_dev);
 
 	slave_disable_netpoll(slave);
 
@@ -2195,7 +2214,7 @@ static int bond_release_all(struct net_device *bond_dev)
 			netif_addr_unlock_bh(bond_dev);
 		}
 
-		netdev_set_bond_master(slave_dev, NULL);
+		bond_upper_dev_unlink(bond_dev, slave_dev);
 
 		slave_disable_netpoll(slave);
 
@@ -2259,8 +2278,9 @@ static int bond_ioctl_change_active(struct net_device *bond_dev, struct net_devi
 	if (!USES_PRIMARY(bond->params.mode))
 		return -EINVAL;
 
-	/* Verify that master_dev is indeed the master of slave_dev */
-	if (!(slave_dev->flags & IFF_SLAVE) || (slave_dev->master != bond_dev))
+	/* Verify that bond_dev is indeed the master of slave_dev */
+	if (!(slave_dev->flags & IFF_SLAVE) ||
+	    !netdev_has_upper_dev(slave_dev, bond_dev))
 		return -EINVAL;
 
 	read_lock(&bond->lock);
@@ -3258,36 +3278,32 @@ static int bond_master_netdev_event(unsigned long event,
 static int bond_slave_netdev_event(unsigned long event,
 				   struct net_device *slave_dev)
 {
-	struct net_device *bond_dev = slave_dev->master;
-	struct bonding *bond = netdev_priv(bond_dev);
-	struct slave *slave = NULL;
+	struct slave *slave = bond_slave_get_rtnl(slave_dev);
+	struct bonding *bond = slave->bond;
+	struct net_device *bond_dev = slave->bond->dev;
+	u32 old_speed;
+	u8 old_duplex;
 
 	switch (event) {
 	case NETDEV_UNREGISTER:
-		if (bond_dev) {
-			if (bond->setup_by_slave)
-				bond_release_and_destroy(bond_dev, slave_dev);
-			else
-				bond_release(bond_dev, slave_dev);
-		}
+		if (bond->setup_by_slave)
+			bond_release_and_destroy(bond_dev, slave_dev);
+		else
+			bond_release(bond_dev, slave_dev);
 		break;
 	case NETDEV_UP:
 	case NETDEV_CHANGE:
-		slave = bond_get_slave_by_dev(bond, slave_dev);
-		if (slave) {
-			u32 old_speed = slave->speed;
-			u8  old_duplex = slave->duplex;
+		old_speed = slave->speed;
+		old_duplex = slave->duplex;
 
-			bond_update_speed_duplex(slave);
+		bond_update_speed_duplex(slave);
 
-			if (bond->params.mode == BOND_MODE_8023AD) {
-				if (old_speed != slave->speed)
-					bond_3ad_adapter_speed_changed(slave);
-				if (old_duplex != slave->duplex)
-					bond_3ad_adapter_duplex_changed(slave);
-			}
+		if (bond->params.mode == BOND_MODE_8023AD) {
+			if (old_speed != slave->speed)
+				bond_3ad_adapter_speed_changed(slave);
+			if (old_duplex != slave->duplex)
+				bond_3ad_adapter_duplex_changed(slave);
 		}
-
 		break;
 	case NETDEV_DOWN:
 		/*
diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h
index 21b68e5..0d282d2 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -258,6 +258,9 @@ static inline bool bond_vlan_used(struct bonding *bond)
 #define bond_slave_get_rcu(dev) \
 	((struct slave *) rcu_dereference(dev->rx_handler_data))
 
+#define bond_slave_get_rtnl(dev) \
+	((struct slave *) rtnl_dereference(dev->rx_handler_data))
+
 /**
  * Returns NULL if the net_device does not belong to any of the bond's slaves
  *
@@ -280,11 +283,9 @@ static inline struct slave *bond_get_slave_by_dev(struct bonding *bond,
 
 static inline struct bonding *bond_get_bond_by_slave(struct slave *slave)
 {
-	if (!slave || !slave->dev->master) {
+	if (!slave || !slave->bond)
 		return NULL;
-	}
-
-	return netdev_priv(slave->dev->master);
+	return slave->bond;
 }
 
 static inline bool bond_is_lb(const struct bonding *bond)
@@ -360,10 +361,9 @@ static inline void bond_netpoll_send_skb(const struct slave *slave,
 
 static inline void bond_set_slave_inactive_flags(struct slave *slave)
 {
-	struct bonding *bond = netdev_priv(slave->dev->master);
-	if (!bond_is_lb(bond))
+	if (!bond_is_lb(slave->bond))
 		bond_set_backup_slave(slave);
-	if (!bond->params.all_slaves_active)
+	if (!slave->bond->params.all_slaves_active)
 		slave->inactive = 1;
 }
 
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index ae612f4..095bbc7 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -2003,6 +2003,7 @@ errout:
 	if (err < 0)
 		rtnl_set_sk_err(net, RTNLGRP_LINK, err);
 }
+EXPORT_SYMBOL(rtmsg_ifinfo);
 
 static int nlmsg_populate_fdb_fill(struct sk_buff *skb,
 				   struct net_device *dev,
-- 
1.8.0

[patch net-next 14/15] net: remove no longer used netdev_set_bond_master() and netdev_set_master()

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 include/linux/netdevice.h |  6 +----
 net/core/dev.c            | 63 -----------------------------------------------
 2 files changed, 1 insertion(+), 68 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 2e5a217..94b5843 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -856,8 +856,7 @@ struct netdev_fcoe_hbainfo {
  *	flow_id is a flow ID to be passed to rps_may_expire_flow() later.
  *	Return the filter ID on success, or a negative error code.
  *
- *	Slave management functions (for bridge, bonding, etc). User should
- *	call netdev_set_master() to set dev->master properly.
+ *	Slave management functions (for bridge, bonding, etc).
  * int (*ndo_add_slave)(struct net_device *dev, struct net_device *slave_dev);
  *	Called to make another netdev an underling.
  *
@@ -2647,9 +2646,6 @@ extern int netdev_master_upper_dev_link(struct net_device *dev,
 					struct net_device *upper_dev);
 extern void netdev_upper_dev_unlink(struct net_device *dev,
 				    struct net_device *upper_dev);
-extern int		netdev_set_master(struct net_device *dev, struct net_device *master);
-extern int netdev_set_bond_master(struct net_device *dev,
-				  struct net_device *master);
 extern int skb_checksum_help(struct sk_buff *skb);
 extern struct sk_buff *skb_gso_segment(struct sk_buff *skb,
 	netdev_features_t features);
diff --git a/net/core/dev.c b/net/core/dev.c
index cf63a85..cdf7a19 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4842,69 +4842,6 @@ void netdev_upper_dev_unlink(struct net_device *dev,
 }
 EXPORT_SYMBOL(netdev_upper_dev_unlink);
 
-/**
- *	netdev_set_master	-	set up master pointer
- *	@slave: slave device
- *	@master: new master device
- *
- *	Changes the master device of the slave. Pass %NULL to break the
- *	bonding. The caller must hold the RTNL semaphore. On a failure
- *	a negative errno code is returned. On success the reference counts
- *	are adjusted and the function returns zero.
- */
-int netdev_set_master(struct net_device *slave, struct net_device *master)
-{
-	struct net_device *old = slave->master;
-	int err;
-
-	ASSERT_RTNL();
-
-	if (master) {
-		if (old)
-			return -EBUSY;
-		err = netdev_master_upper_dev_link(slave, master);
-		if (err)
-			return err;
-	}
-
-	slave->master = master;
-
-	if (old)
-		netdev_upper_dev_unlink(slave, master);
-
-	return 0;
-}
-EXPORT_SYMBOL(netdev_set_master);
-
-/**
- *	netdev_set_bond_master	-	set up bonding master/slave pair
- *	@slave: slave device
- *	@master: new master device
- *
- *	Changes the master device of the slave. Pass %NULL to break the
- *	bonding. The caller must hold the RTNL semaphore. On a failure
- *	a negative errno code is returned. On success %RTM_NEWLINK is sent
- *	to the routing socket and the function returns zero.
- */
-int netdev_set_bond_master(struct net_device *slave, struct net_device *master)
-{
-	int err;
-
-	ASSERT_RTNL();
-
-	err = netdev_set_master(slave, master);
-	if (err)
-		return err;
-	if (master)
-		slave->flags |= IFF_SLAVE;
-	else
-		slave->flags &= ~IFF_SLAVE;
-
-	rtmsg_ifinfo(RTM_NEWLINK, slave, IFF_SLAVE);
-	return 0;
-}
-EXPORT_SYMBOL(netdev_set_bond_master);
-
 static void dev_change_rx_flags(struct net_device *dev, int flags)
 {
 	const struct net_device_ops *ops = dev->netdev_ops;
-- 
1.8.0

[patch net-next 15/15] net: kill dev->master

[Jiri Pirko]

Nobody uses this now. Remove it.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 include/linux/netdevice.h | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 94b5843..07ad1c3 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1167,10 +1167,6 @@ struct net_device {
 						 * avoid dirtying this cache line.
 						 */
 
-	struct net_device	*master; /* Pointer to master device of a group,
-					  * which this device is member of.
-					  */
-
 	struct list_head	upper_dev_list; /* List of upper devices */
 
 	/* Interface address info used in eth_type_trans() */
-- 
1.8.0

Re: [patch net-next 01/15] net: introduce upper device lists

[David Miller]

From: Jiri Pirko <jiri@resnulli.us>
Date: Sat, 29 Dec 2012 11:38:28 +0100

> +	/*
> +	 * To prevent loops, check if dev is not upper device to upper_dev.
> +	 */

Please use:

	/* To prevent loops, check if dev is not upper device to upper_dev.  */

> +/**
> + * netdev_upper_free_rcu - Frees a upper device list item via the RCU pointer
> + * @entry: the entry's RCU field
> + *
> + * This function is designed to be used as a callback to the call_rcu()
> + * function so that the memory allocated to the netdev upper device list item
> + * can be released safely.
> + */
> +static void netdev_upper_free_rcu(struct rcu_head *entry)
> +{
> +	struct netdev_upper *upper;
> +
> +	upper = container_of(entry, struct netdev_upper, rcu);
> +	kfree(upper);
> +}

Please use kfree_rcu().

Also, since __netdev_has_upper_dev() modifies &search_list inside
of the list traversal loop, I think you really need to use
list_for_each_entry_safe() even though you always append to the
tail of &search_list.

Re: [patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

Sun, Dec 30, 2012 at 12:31:01AM CET, davem@davemloft.net wrote:
>From: Jiri Pirko <jiri@resnulli.us>
>Date: Sat, 29 Dec 2012 11:38:28 +0100
>
>> +	/*
>> +	 * To prevent loops, check if dev is not upper device to upper_dev.
>> +	 */
>
>Please use:
>
>	/* To prevent loops, check if dev is not upper device to upper_dev.  */

fixed

>
>> +/**
>> + * netdev_upper_free_rcu - Frees a upper device list item via the RCU pointer
>> + * @entry: the entry's RCU field
>> + *
>> + * This function is designed to be used as a callback to the call_rcu()
>> + * function so that the memory allocated to the netdev upper device list item
>> + * can be released safely.
>> + */
>> +static void netdev_upper_free_rcu(struct rcu_head *entry)
>> +{
>> +	struct netdev_upper *upper;
>> +
>> +	upper = container_of(entry, struct netdev_upper, rcu);
>> +	kfree(upper);
>> +}
>
>Please use kfree_rcu().

fixed

>
>Also, since __netdev_has_upper_dev() modifies &search_list inside
>of the list traversal loop, I think you really need to use
>list_for_each_entry_safe() even though you always append to the
>tail of &search_list.

Hmm, I do not believe that list_for_each_entry_safe() would work correctly
here. In case that the current iterator is at the very end of
the list and now other items are added, list_for_each_entry_safe() would
remember that next is head and the newly added items would not be
processed. list_for_each_entry() works just fine in any case I can
imagine. Note that no items are removed during the iteration.
Am I missing something?

Thanks!

Jiri

[patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

This lists are supposed to serve for storing pointers to all upper devices.
Eventually it will replace dev->master pointer which is used for
bonding, bridge, team but it cannot be used for vlan, macvlan where
there might be multiple upper present. In case the upper link is
replacement for dev->master, it is marked with "master" flag.

New upper device list resolves this limitation. Also, the information
stored in lists is used for preventing looping setups like
"bond->somethingelse->samebond"

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 include/linux/netdevice.h |  14 +++
 net/core/dev.c            | 237 +++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 247 insertions(+), 4 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 6835b58..52d1146 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1172,6 +1172,8 @@ struct net_device {
 					  * which this device is member of.
 					  */
 
+	struct list_head	upper_dev_list; /* List of upper devices */
+
 	/* Interface address info used in eth_type_trans() */
 	unsigned char		*dev_addr;	/* hw address, (before bcast
 						   because most packets are
@@ -2634,6 +2636,18 @@ extern int		netdev_max_backlog;
 extern int		netdev_tstamp_prequeue;
 extern int		weight_p;
 extern int		bpf_jit_enable;
+
+extern bool netdev_has_upper_dev(struct net_device *dev,
+				 struct net_device *upper_dev);
+extern bool netdev_has_any_upper_dev(struct net_device *dev);
+extern struct net_device *netdev_master_upper_dev_get(struct net_device *dev);
+extern struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev);
+extern int netdev_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev);
+extern int netdev_master_upper_dev_link(struct net_device *dev,
+					struct net_device *upper_dev);
+extern void netdev_upper_dev_unlink(struct net_device *dev,
+				    struct net_device *upper_dev);
 extern int		netdev_set_master(struct net_device *dev, struct net_device *master);
 extern int netdev_set_bond_master(struct net_device *dev,
 				  struct net_device *master);
diff --git a/net/core/dev.c b/net/core/dev.c
index 21c5b97..1af3141 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4600,6 +4600,230 @@ static int __init dev_proc_init(void)
 #endif	/* CONFIG_PROC_FS */
 
 
+struct netdev_upper {
+	struct net_device *dev;
+	bool master;
+	struct list_head list;
+	struct rcu_head rcu;
+	struct list_head search_list;
+};
+
+static void __append_search_uppers(struct list_head *search_list,
+				   struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	list_for_each_entry(upper, &dev->upper_dev_list, list) {
+		/* check if this upper is not already in search list */
+		if (list_empty(&upper->search_list))
+			list_add_tail(&upper->search_list, search_list);
+	}
+}
+
+static bool __netdev_has_upper_dev(struct net_device *dev,
+				   struct net_device *upper_dev)
+{
+	LIST_HEAD(search_list);
+	struct netdev_upper *upper;
+	struct netdev_upper *tmp;
+	bool ret = false;
+
+	__append_search_uppers(&search_list, dev);
+	list_for_each_entry(upper, &search_list, search_list) {
+		if (upper->dev == upper_dev) {
+			ret = true;
+			break;
+		}
+		__append_search_uppers(&search_list, upper->dev);
+	}
+	list_for_each_entry_safe(upper, tmp, &search_list, search_list)
+		INIT_LIST_HEAD(&upper->search_list);
+	return ret;
+}
+
+static struct netdev_upper *__netdev_find_upper(struct net_device *dev,
+						struct net_device *upper_dev)
+{
+	struct netdev_upper *upper;
+
+	list_for_each_entry(upper, &dev->upper_dev_list, list) {
+		if (upper->dev == upper_dev)
+			return upper;
+	}
+	return NULL;
+}
+
+/**
+ * netdev_has_upper_dev - Check if device is linked to an upper device
+ * @dev: device
+ * @upper_dev: upper device to check
+ *
+ * Find out if a device is linked to specified upper device and return true
+ * in case it is. The caller must hold the RTNL semaphore.
+ */
+bool netdev_has_upper_dev(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	ASSERT_RTNL();
+
+	return __netdev_find_upper(dev, upper_dev);
+}
+EXPORT_SYMBOL(netdev_has_upper_dev);
+
+/**
+ * netdev_has_any_upper_dev - Check if device is linked to some device
+ * @dev: device
+ *
+ * Find out if a device is linked to an upper device and return true in case
+ * it is. The caller must hold the RTNL semaphore.
+ */
+bool netdev_has_any_upper_dev(struct net_device *dev)
+{
+	ASSERT_RTNL();
+
+	return !list_empty(&dev->upper_dev_list);
+}
+EXPORT_SYMBOL(netdev_has_any_upper_dev);
+
+/**
+ * netdev_master_upper_dev_get - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RTNL semaphore.
+ */
+struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	if (list_empty(&dev->upper_dev_list))
+		return NULL;
+
+	upper = list_first_entry(&dev->upper_dev_list,
+				 struct netdev_upper, list);
+	if (likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get);
+
+/**
+ * netdev_master_upper_dev_get_rcu - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RCU read lock.
+ */
+struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
+{
+	struct netdev_upper *upper;
+
+	upper = list_first_or_null_rcu(&dev->upper_dev_list,
+				       struct netdev_upper, list);
+	if (upper && likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
+
+static int __netdev_upper_dev_link(struct net_device *dev,
+				   struct net_device *upper_dev, bool master)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	if (dev == upper_dev)
+		return -EBUSY;
+
+	/* To prevent loops, check if dev is not upper device to upper_dev. */
+	if (__netdev_has_upper_dev(upper_dev, dev))
+		return -EBUSY;
+
+	if (__netdev_find_upper(dev, upper_dev))
+		return -EEXIST;
+
+	if (master && netdev_master_upper_dev_get(dev))
+		return -EBUSY;
+
+	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
+	if (!upper)
+		return -ENOMEM;
+
+	upper->dev = upper_dev;
+	upper->master = master;
+	INIT_LIST_HEAD(&upper->search_list);
+
+	/* Ensure that master upper link is always the first item in list. */
+	if (master)
+		list_add_rcu(&upper->list, &dev->upper_dev_list);
+	else
+		list_add_tail_rcu(&upper->list, &dev->upper_dev_list);
+	dev_hold(upper_dev);
+
+	return 0;
+}
+/**
+ * netdev_upper_dev_link - Add a link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. The caller must hold
+ * the RTNL semaphore. On a failure a negative errno code is returned.
+ * On success the reference counts are adjusted and the function
+ * returns zero.
+ */
+int netdev_upper_dev_link(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, false);
+}
+EXPORT_SYMBOL(netdev_upper_dev_link);
+
+/**
+ * netdev_master_upper_dev_link - Add a master link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. In this case, only
+ * one master upper device can be linked, although other non-master devices
+ * might be linked as well. The caller must hold the RTNL semaphore.
+ * On a failure a negative errno code is returned. On success the reference
+ * counts are adjusted and the function returns zero.
+ */
+int netdev_master_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, true);
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_link);
+
+/**
+ * netdev_upper_dev_unlink - Removes a link to upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Removes a link to device which is upper to this one. The caller must hold
+ * the RTNL semaphore.
+ */
+void netdev_upper_dev_unlink(struct net_device *dev,
+			     struct net_device *upper_dev)
+{
+	struct netdev_upper *upper;
+
+	ASSERT_RTNL();
+
+	upper = __netdev_find_upper(dev, upper_dev);
+	if (!upper)
+		return;
+	list_del_rcu(&upper->list);
+	dev_put(upper_dev);
+	kfree_rcu(upper, rcu);
+}
+EXPORT_SYMBOL(netdev_upper_dev_unlink);
+
 /**
  *	netdev_set_master	-	set up master pointer
  *	@slave: slave device
@@ -4613,19 +4837,23 @@ static int __init dev_proc_init(void)
 int netdev_set_master(struct net_device *slave, struct net_device *master)
 {
 	struct net_device *old = slave->master;
+	int err;
 
 	ASSERT_RTNL();
 
 	if (master) {
 		if (old)
 			return -EBUSY;
-		dev_hold(master);
+		err = netdev_master_upper_dev_link(slave, master);
+		if (err)
+			return err;
 	}
 
 	slave->master = master;
 
 	if (old)
-		dev_put(old);
+		netdev_upper_dev_unlink(slave, master);
+
 	return 0;
 }
 EXPORT_SYMBOL(netdev_set_master);
@@ -5501,8 +5729,8 @@ static void rollback_registered_many(struct list_head *head)
 		if (dev->netdev_ops->ndo_uninit)
 			dev->netdev_ops->ndo_uninit(dev);
 
-		/* Notifier chain MUST detach us from master device. */
-		WARN_ON(dev->master);
+		/* Notifier chain MUST detach us all upper devices. */
+		WARN_ON(netdev_has_any_upper_dev(dev));
 
 		/* Remove entries from kobject tree */
 		netdev_unregister_kobject(dev);
@@ -6210,6 +6438,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
 	INIT_LIST_HEAD(&dev->napi_list);
 	INIT_LIST_HEAD(&dev->unreg_list);
 	INIT_LIST_HEAD(&dev->link_watch_list);
+	INIT_LIST_HEAD(&dev->upper_dev_list);
 	dev->priv_flags = IFF_XMIT_DST_RELEASE;
 	setup(dev);
 
-- 
1.8.0

Re: [patch net-next 01/15] net: introduce upper device lists

[Ben Greear]

On 12/30/2012 03:58 AM, Jiri Pirko wrote:
> This lists are supposed to serve for storing pointers to all upper devices.
> Eventually it will replace dev->master pointer which is used for
> bonding, bridge, team but it cannot be used for vlan, macvlan where
> there might be multiple upper present. In case the upper link is
> replacement for dev->master, it is marked with "master" flag.

This is confusing and full of grammatical errors.  For instance, the 'it'
in "team but it cannot be used"...you are talking about the list this
patch introduces, or the old dev->master?

>
> New upper device list resolves this limitation. Also, the information
> stored in lists is used for preventing looping setups like
> "bond->somethingelse->samebond"
>
> Signed-off-by: Jiri Pirko <jiri@resnulli.us>
> ---
>   include/linux/netdevice.h |  14 +++
>   net/core/dev.c            | 237 +++++++++++++++++++++++++++++++++++++++++++++-
>   2 files changed, 247 insertions(+), 4 deletions(-)
>
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index 6835b58..52d1146 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -1172,6 +1172,8 @@ struct net_device {
>   					  * which this device is member of.
>   					  */
>
> +	struct list_head	upper_dev_list; /* List of upper devices */
> +

Unless I mis-understand, this is often contains 'lower' devices instead,
and could contain a mixture.
Maybe this could use a rename, or at least a lot more comments?

Thanks,
Ben

-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com

Re: [patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

Sun, Dec 30, 2012 at 07:00:42PM CET, greearb@candelatech.com wrote:
>On 12/30/2012 03:58 AM, Jiri Pirko wrote:
>>This lists are supposed to serve for storing pointers to all upper devices.
>>Eventually it will replace dev->master pointer which is used for
>>bonding, bridge, team but it cannot be used for vlan, macvlan where
>>there might be multiple upper present. In case the upper link is
>>replacement for dev->master, it is marked with "master" flag.
>
>This is confusing and full of grammatical errors.  For instance, the 'it'
>in "team but it cannot be used"...you are talking about the list this
>patch introduces, or the old dev->master?

Sorry for my grammar, it stinks...

dev->master cannot be used for for vlan, macvlan. More upper devices
might be present for this type of devices and dev->master would not cover it.

So, In case there is only *one* upper device, "master" flag is used.

I Hope I cleared this one for you.


>
>>
>>New upper device list resolves this limitation. Also, the information
>>stored in lists is used for preventing looping setups like
>>"bond->somethingelse->samebond"
>>
>>Signed-off-by: Jiri Pirko <jiri@resnulli.us>
>>---
>>  include/linux/netdevice.h |  14 +++
>>  net/core/dev.c            | 237 +++++++++++++++++++++++++++++++++++++++++++++-
>>  2 files changed, 247 insertions(+), 4 deletions(-)
>>
>>diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
>>index 6835b58..52d1146 100644
>>--- a/include/linux/netdevice.h
>>+++ b/include/linux/netdevice.h
>>@@ -1172,6 +1172,8 @@ struct net_device {
>>  					  * which this device is member of.
>>  					  */
>>
>>+	struct list_head	upper_dev_list; /* List of upper devices */
>>+
>
>Unless I mis-understand, this is often contains 'lower' devices instead,
>and could contain a mixture.
>Maybe this could use a rename, or at least a lot more comments?

I'm terribly sorry, but I believe this is the case when I do not
understand your grammar. For example "this is often contains 'lower'
devices instead".

But in any case, no, list of upper devices contains only "upper" devices.
Meaning the set of devices which are using the original one as "lower".
Never the other way.

And to reply to your comment to patch "[patch net-next 04/15] rtnetlink:
remove usage of dev->master" as well:

upper dev is the device that is somehow using the lower dev for its
work. For bonding, you may call that lower device "slave", for bridge,
"port". And macvlan is also linked to it's lower device, the one on what
it is hooked on by rx_handler.


I hope this clears this for you a bit.

Thanks

Jiri.

>
>Thanks,
>Ben
>
>-- 
>Ben Greear <greearb@candelatech.com>
>Candela Technologies Inc  http://www.candelatech.com
>
>

Re: [patch net-next 01/15] net: introduce upper device lists

[Stephen Hemminger]

On Sun, 30 Dec 2012 12:58:08 +0100
Jiri Pirko <jiri@resnulli.us> wrote:

> This lists are supposed to serve for storing pointers to all upper devices.
> Eventually it will replace dev->master pointer which is used for
> bonding, bridge, team but it cannot be used for vlan, macvlan where
> there might be multiple upper present. In case the upper link is
> replacement for dev->master, it is marked with "master" flag.
> 
> New upper device list resolves this limitation. Also, the information
> stored in lists is used for preventing looping setups like
> "bond->somethingelse->samebond"
> 
> Signed-off-by: Jiri Pirko <jiri@resnulli.us>

What is the use case for this?
Could you describe a topology that the new upper device list supports,
that the old scheme does not?

I am concerned that it may open up many new possibilities for user
error that were not possible before. For example how does it prevent
an ethernet from being assigned to both a bonding and bridge at the
same time?

Re: [patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

Mon, Dec 31, 2012 at 05:56:33AM CET, shemminger@vyatta.com wrote:
>On Sun, 30 Dec 2012 12:58:08 +0100
>Jiri Pirko <jiri@resnulli.us> wrote:
>
>> This lists are supposed to serve for storing pointers to all upper devices.
>> Eventually it will replace dev->master pointer which is used for
>> bonding, bridge, team but it cannot be used for vlan, macvlan where
>> there might be multiple upper present. In case the upper link is
>> replacement for dev->master, it is marked with "master" flag.
>> 
>> New upper device list resolves this limitation. Also, the information
>> stored in lists is used for preventing looping setups like
>> "bond->somethingelse->samebond"
>> 
>> Signed-off-by: Jiri Pirko <jiri@resnulli.us>
>
>What is the use case for this?
>Could you describe a topology that the new upper device list supports,
>that the old scheme does not?


The old scheme is not possible to track the upper-lower dependencies for
all types of devices. (dev->master is used by bonding,bridge,team only).
My new scheme using upper lists allows to track all dependencies. That
provides ability to prevent loops in the dependency trees.


>
>I am concerned that it may open up many new possibilities for user
>error that were not possible before. For example how does it prevent
>an ethernet from being assigned to both a bonding and bridge at the
>same time?

No. netdev_master_upper_dev_link() is used in bond,bridge,team etc.
This function ensures that only one upper device marked as "master" is
present at a time.

This patchset does not introduce any possibility for user error. Only
prevents one group of them - loops.

Re: [patch net-next 01/15] net: introduce upper device lists

[Stephen Hemminger]

On Sun, 30 Dec 2012 12:58:08 +0100
Jiri Pirko <jiri@resnulli.us> wrote:

> This lists are supposed to serve for storing pointers to all upper devices.
> Eventually it will replace dev->master pointer which is used for
> bonding, bridge, team but it cannot be used for vlan, macvlan where
> there might be multiple upper present. In case the upper link is
> replacement for dev->master, it is marked with "master" flag.
> 
> New upper device list resolves this limitation. Also, the information
> stored in lists is used for preventing looping setups like
> "bond->somethingelse->samebond"
> 
> Signed-off-by: Jiri Pirko <jiri@resnulli.us>

I like the concept of knowing the topology of layered network devices.
The name "upper device lists" is a little confusing to me.
Also, the amount of additional data structures and book keeping
seems more than needed; but not sure how to reduce it down to the
least code.

For simple case of detecting loops, just using existing master
pointer is sufficient.
       ethernet --> bonding --> bridge --+
                       ^                 |
                       |                 |
                       +-----------------+
This is the simple case of detecting if singularly linked list
is a loop.

The only device where multiple upper devices is possible seems
to be macvlan. Could the special case code be limited to there?

Re: [patch net-next 01/15] net: introduce upper device lists

[Jiri Pirko]

Mon, Dec 31, 2012 at 08:22:12PM CET, shemminger@vyatta.com wrote:
>On Sun, 30 Dec 2012 12:58:08 +0100
>Jiri Pirko <jiri@resnulli.us> wrote:
>
>> This lists are supposed to serve for storing pointers to all upper devices.
>> Eventually it will replace dev->master pointer which is used for
>> bonding, bridge, team but it cannot be used for vlan, macvlan where
>> there might be multiple upper present. In case the upper link is
>> replacement for dev->master, it is marked with "master" flag.
>> 
>> New upper device list resolves this limitation. Also, the information
>> stored in lists is used for preventing looping setups like
>> "bond->somethingelse->samebond"
>> 
>> Signed-off-by: Jiri Pirko <jiri@resnulli.us>
>
>I like the concept of knowing the topology of layered network devices.
>The name "upper device lists" is a little confusing to me.

Well, it's a list of devices "upper" to this one. Please provide more
suitable name alternative. I can't think of any, in fact I think "upper"
is pretty suitable.


>Also, the amount of additional data structures and book keeping
>seems more than needed; but not sure how to reduce it down to the
>least code.

Yep, that's it. I tried to make that as slim as possible. Trimming ideas
are very welcome.

>
>For simple case of detecting loops, just using existing master
>pointer is sufficient.
>       ethernet --> bonding --> bridge --+
>                       ^                 |
>                       |                 |
>                       +-----------------+
>This is the simple case of detecting if singularly linked list
>is a loop.
>
>The only device where multiple upper devices is possible seems
>to be macvlan. Could the special case code be limited to there?

Well, there are others, vlan for example. And the whole concept is to
make this uniform and generic, to avoid specific code for specific
drivers. And there are some usecases which can benefit from the upper
lists, like for example drivers which need to obtain l3 address info
(cxgb3, qlcnic, qeth).

But in any case, I doubt that this alternative approach will
lead to much smaller code footprint. I think it would be just more
messy.