[patch net-next 00/16] net: introduce upper device lists and remove dev->master

[patch net-next 00/16] net: introduce upper device lists and remove dev->master

[Jiri Pirko]

Hi all.

Recent 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
"unique links" have the same value.

After all changes, there is no longer possible to do:
"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.

Jiri Pirko (16):
  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: remove usage of dev->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                                     |  241 +++++++++++++++++---
 net/core/netpoll.c                                 |    8 +-
 net/core/rtnetlink.c                               |   45 ++--
 18 files changed, 392 insertions(+), 168 deletions(-)

-- 
1.7.10.4

[patch net-next 01/16] 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 "masters" present.

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            |  232 ++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 244 insertions(+), 2 deletions(-)

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index a9db4f3..e7a07f8 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1173,6 +1173,8 @@ 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
@@ -2611,6 +2613,18 @@ 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_unique_upper_dev_get(struct net_device *dev);
+extern struct net_device *netdev_unique_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_unique_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 1f06df8..68db1ac 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void)
 #endif	/* CONFIG_PROC_FS */
 
 
+struct netdev_upper {
+	struct net_device *dev;
+	bool unique;
+	struct list_head list;
+	struct rcu_head rcu;
+};
+
+static bool __netdev_has_upper_dev(struct net_device *dev,
+				   struct net_device *upper_dev,
+				   bool deep)
+{
+	struct netdev_upper *upper;
+
+	list_for_each_entry(upper, &dev->upper_dev_list, list) {
+		if (upper->dev == upper_dev)
+			return true;
+		if (deep && __netdev_has_upper_dev(upper->dev, upper_dev, deep))
+			return true;
+	}
+	return false;
+}
+
+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_has_upper_dev(dev, upper_dev, false);
+}
+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_unique_upper_dev_get - Get unique upper device
+ * @dev: device
+ *
+ * Find a unique 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_unique_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->unique))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_unique_upper_dev_get);
+
+/**
+ * netdev_unique_upper_dev_get_rcu - Get unique upper device
+ * @dev: device
+ *
+ * Find a unique 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_unique_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 (likely(upper->unique))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_unique_upper_dev_get_rcu);
+
+static int __netdev_upper_dev_link(struct net_device *dev,
+				   struct net_device *upper_dev, bool unique)
+{
+	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, true))
+		return -EBUSY;
+
+	if (__netdev_find_upper(dev, upper_dev))
+		return -EEXIST;
+
+	if (unique && netdev_unique_upper_dev_get(dev))
+		return -EBUSY;
+
+	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
+	if (!upper)
+		return -ENOMEM;
+
+	upper->dev = upper_dev;
+	upper->unique = unique;
+
+	/*
+	 * Ensure that unique upper link is always the first item in the list.
+	 */
+	if (unique)
+		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_unique_upper_dev_link - Add a unique 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 unique upper device can be linked, although other non-unique 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_unique_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, true);
+}
+EXPORT_SYMBOL(netdev_unique_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
@@ -4438,19 +4661,23 @@ 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_unique_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);
@@ -5999,6 +6226,7 @@ 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);
 
-- 
1.7.10.4

[patch net-next 02/16] 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 66a9bfe..f5bd8a2 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);
 
-- 
1.7.10.4

[patch net-next 03/16] 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 9096bcb..739665e 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;
 
+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);
-- 
1.7.10.4

[patch net-next 04/16] rtnetlink: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/core/rtnetlink.c |   44 ++++++++++++++++++++++++--------------------
 1 file changed, 24 insertions(+), 20 deletions(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index 34d975b..c341eb7 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -879,6 +879,7 @@ 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_unique_upper_dev_get(dev);
 
 	ASSERT_RTNL();
 	nlh = nlmsg_put(skb, pid, seq, type, sizeof(*ifm), flags);
@@ -907,8 +908,8 @@ 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)) ||
 	    (dev->qdisc &&
 	     nla_put_string(skb, IFLA_QDISC, dev->qdisc->ops->id)) ||
 	    (dev->ifalias &&
@@ -1270,16 +1271,16 @@ 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_unique_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 {
@@ -1288,12 +1289,12 @@ 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 {
@@ -2050,7 +2051,6 @@ 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;
@@ -2089,9 +2089,10 @@ 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, dev, addr,
-						      nlh->nlmsg_flags);
+		struct net_device *br_dev = netdev_unique_upper_dev_get(dev);
+		const struct net_device_ops *ops = br_dev->netdev_ops;
+
+		err = ops->ndo_fdb_add(ndm, dev, addr, nlh->nlmsg_flags);
 		if (err)
 			goto out;
 		else
@@ -2148,10 +2149,11 @@ 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_unique_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;
@@ -2234,9 +2236,11 @@ 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_unique_upper_dev_get(dev);
+			ops = br_dev->netdev_ops;
 			if (ops->ndo_fdb_dump)
 				idx = ops->ndo_fdb_dump(skb, cb, dev, idx);
 		}
-- 
1.7.10.4

[patch net-next 05/16] 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 ba10c46..0533cbf 100644
--- a/drivers/net/team/team.c
+++ b/drivers/net/team/team.c
@@ -1040,10 +1040,11 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
 		}
 	}
 
-	err = netdev_set_master(port_dev, dev);
+	err = netdev_unique_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,
@@ -1076,9 +1077,9 @@ 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:
@@ -1121,7 +1122,7 @@ 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);
-- 
1.7.10.4

[patch net-next 06/16] 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 e1144e1..5933900 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))))
 		goto err3;
 
-	err = netdev_set_master(dev, br->dev);
+	err = netdev_unique_upper_dev_link(dev, br->dev);
 	if (err)
 		goto err3;
 
@@ -403,7 +403,7 @@ int br_add_if(struct net_bridge *br, struct net_device *dev)
 	return 0;
 
 err4:
-	netdev_set_master(dev, NULL);
+	netdev_upper_dev_unlink(dev, br->dev);
 err3:
 	sysfs_remove_link(br->ifobj, p->dev->name);
 err2:
-- 
1.7.10.4

[patch net-next 07/16] netpoll: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/core/netpoll.c |    8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index b4c90e4..5c8e560 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -207,12 +207,16 @@ static void netpoll_poll_dev(struct net_device *dev)
 
 	if (dev->flags & IFF_SLAVE) {
 		if (dev->npinfo) {
-			struct net_device *bond_dev = dev->master;
+			struct net_device *bond_dev;
 			struct sk_buff *skb;
+
+			rcu_read_lock();
+			bond_dev = netdev_unique_upper_dev_get_rcu(dev);
 			while ((skb = skb_dequeue(&dev->npinfo->arp_tx))) {
 				skb->dev = bond_dev;
 				skb_queue_tail(&bond_dev->npinfo->arp_tx, skb);
 			}
+			rcu_read_unlock();
 		}
 	}
 
@@ -795,7 +799,7 @@ int netpoll_setup(struct netpoll *np)
 		return -ENODEV;
 	}
 
-	if (ndev->master) {
+	if (netdev_unique_upper_dev_get(ndev)) {
 		np_err(np, "%s is a slave device, aborting\n", np->dev_name);
 		err = -EBUSY;
 		goto put;
-- 
1.7.10.4

[patch net-next 08/16] 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 2dbbcbb..28365db 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_unique_upper_dev_get_rcu(dev)))
+					dev = upper_dev;
 			}
+			rcu_read_unlock();
 			return dev;
 		}
 	}
-- 
1.7.10.4

[patch net-next 09/16] 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 212c121..9eadf17 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -4425,12 +4425,14 @@ 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,
-- 
1.7.10.4

[patch net-next 10/16] 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 c5f03fa..6b3988b 100644
--- a/drivers/s390/net/qeth_l3_main.c
+++ b/drivers/s390/net/qeth_l3_main.c
@@ -1638,6 +1638,7 @@ 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;
@@ -1650,19 +1651,14 @@ 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);
 	}
 }
 
@@ -1671,14 +1667,14 @@ 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
@@ -1703,6 +1699,7 @@ 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;
@@ -1739,10 +1736,12 @@ 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 */
@@ -1811,8 +1810,10 @@ 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)
-- 
1.7.10.4

[patch net-next 11/16] 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 8ca533c..f9518ad 100644
--- a/net/8021q/vlan_core.c
+++ b/net/8021q/vlan_core.c
@@ -66,21 +66,25 @@ bool vlan_do_receive(struct sk_buff **skbp, bool last_handler)
 	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 unique 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_unique_upper_dev_get_rcu(dev);
+		if (upper_dev)
+			return __vlan_find_dev_deep(upper_dev, vlan_id);
 	}
 
 	return NULL;
-- 
1.7.10.4

[patch net-next 12/16] 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 7140199..e58e9af 100644
--- a/drivers/infiniband/hw/nes/nes.c
+++ b/drivers/infiniband/hw/nes/nes.c
@@ -140,6 +140,7 @@ 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;
 
@@ -150,8 +151,9 @@ 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_unique_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"
@@ -184,9 +186,9 @@ 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 020e95c..15e6340 100644
--- a/drivers/infiniband/hw/nes/nes_cm.c
+++ b/drivers/infiniband/hw/nes/nes_cm.c
@@ -1352,7 +1352,7 @@ 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;
 
-- 
1.7.10.4

[patch net-next 13/16] 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 e15cc11..6dc3625 100644
--- a/drivers/net/bonding/bond_alb.c
+++ b/drivers/net/bonding/bond_alb.c
@@ -491,7 +491,7 @@ 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;
 		}
 
@@ -501,7 +501,7 @@ 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;
 			}
 		}
@@ -914,7 +914,7 @@ 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 6fae5f3..de75541 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -752,11 +752,9 @@ 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();
 }
 
 /*
@@ -766,9 +764,10 @@ 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;
@@ -780,18 +779,14 @@ 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_unique_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);
 	}
@@ -800,13 +795,16 @@ 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();
 }
 
 /*
@@ -1494,6 +1492,27 @@ static rx_handler_result_t bond_handle_frame(struct sk_buff **pskb)
 	return ret;
 }
 
+static int bond_unique_upper_dev_link(struct net_device *bond_dev,
+				      struct net_device *slave_dev)
+{
+	int err;
+
+	err = netdev_unique_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_unique_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_unique_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);
@@ -3249,36 +3269,32 @@ 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 f8af2fc..c9cd1c0 100644
--- a/drivers/net/bonding/bonding.h
+++ b/drivers/net/bonding/bonding.h
@@ -257,6 +257,9 @@ 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
  *
@@ -279,11 +282,9 @@ 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)
@@ -359,10 +360,9 @@ 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 c341eb7..df16052 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1989,6 +1989,7 @@ 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,
-- 
1.7.10.4

[patch net-next 14/16] 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 e7a07f8..757f627 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -886,8 +886,7 @@ 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.
  *
@@ -2625,9 +2624,6 @@ extern int netdev_unique_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 68db1ac..c0f9adb 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4648,69 +4648,6 @@ 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_unique_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;
-- 
1.7.10.4

[patch net-next 15/16] net: remove usage of dev->master

[Jiri Pirko]

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
---
 net/core/dev.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/core/dev.c b/net/core/dev.c
index c0f9adb..8977404 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5461,8 +5461,8 @@ 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);
-- 
1.7.10.4

[patch net-next 16/16] 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 757f627..28c5ef0 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -1168,10 +1168,6 @@ 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() */
-- 
1.7.10.4

Re: [patch net-next 01/16] net: introduce upper device lists

[Ben Hutchings]

On Mon, 2012-08-13 at 17:27 +0200, 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 "masters" present.
> 
> 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>
[...]
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void)
>  #endif	/* CONFIG_PROC_FS */
>  
> 
> +struct netdev_upper {
> +	struct net_device *dev;
> +	bool unique;

This needs a better name.  It doesn't really have anything to do with
uniqueness and doesn't ensure exclusivity.  I think that it would be
fine to keep the 'master' term.

> +	struct list_head list;
> +	struct rcu_head rcu;
> +};
[...]
> +static int __netdev_upper_dev_link(struct net_device *dev,
> +				   struct net_device *upper_dev, bool unique)
> +{
> +	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, true))
> +		return -EBUSY;
> +
> +	if (__netdev_find_upper(dev, upper_dev))
> +		return -EEXIST;
> +
> +	if (unique && netdev_unique_upper_dev_get(dev))
> +		return -EBUSY;
> +
> +	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
> +	if (!upper)
> +		return -ENOMEM;
> +
> +	upper->dev = upper_dev;
> +	upper->unique = unique;
> +
> +	/*
> +	 * Ensure that unique upper link is always the first item in the list.
> +	 */
> +	if (unique)
> +		list_add_rcu(&upper->list, &dev->upper_dev_list);
> +	else
> +		list_add_tail_rcu(&upper->list, &dev->upper_dev_list);
> +	dev_hold(upper_dev);

This behaviour (calling dev_hold()) matches netdev_set_master().  But
it's oddly asymmetric: generally the administrator can remove either the
upper device or the lower device (rtnl_link_ops or unbinding a physical
device) and the upper device driver must then unlink itself from the
lower device (using a notifier to catch lower device removal).

If the upper device driver fails to unlink when the upper device is
unregistered, then this extra reference causes netdev_wait_allrefs() to
hang... is that the intent?  Or should there be a more explicit counter
and check on unregistration, e.g. WARN_ON(dev->num_lower_devs != 0)?

If it fails to unlink when the lower device is removed, this warning in
rollback_registered_many() may be triggered:

		/* Notifier chain MUST detach us from master device. */
		WARN_ON(dev->master);

I think that needs to become WARN_ON(netdev_has_upper_dev(dev)).

> +	return 0;
> +}
[...] 

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [patch net-next 15/16] net: remove usage of dev->master

[Ben Hutchings]

On Mon, 2012-08-13 at 17:27 +0200, Jiri Pirko wrote:
> Signed-off-by: Jiri Pirko <jiri@resnulli.us>
> ---
>  net/core/dev.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/net/core/dev.c b/net/core/dev.c
> index c0f9adb..8977404 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -5461,8 +5461,8 @@ 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);

I think this should be folded into patch 1, since that already ensures
that any master device is included in the upper device list.

Ben.

-- 
Ben Hutchings, Staff Engineer, Solarflare
Not speaking for my employer; that's the marketing department's job.
They asked us to note that Solarflare product names are trademarked.

Re: [patch net-next 01/16] net: introduce upper device lists

[Jiri Pirko]

Mon, Aug 13, 2012 at 07:04:11PM CEST, bhutchings@solarflare.com wrote:
>On Mon, 2012-08-13 at 17:27 +0200, 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 "masters" present.
>> 
>> 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>
>[...]
>> --- a/net/core/dev.c
>> +++ b/net/core/dev.c
>> @@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void)
>>  #endif	/* CONFIG_PROC_FS */
>>  
>> 
>> +struct netdev_upper {
>> +	struct net_device *dev;
>> +	bool unique;
>
>This needs a better name.  It doesn't really have anything to do with
>uniqueness and doesn't ensure exclusivity.  I think that it would be
>fine to keep the 'master' term.

Hmm. I admit that "unique" I do not like too much as well. But "master"
I like even less.

This flag should ensure exclusivity. Only one upper device with this
flag can be present at a time.

>
>> +	struct list_head list;
>> +	struct rcu_head rcu;
>> +};
>[...]
>> +static int __netdev_upper_dev_link(struct net_device *dev,
>> +				   struct net_device *upper_dev, bool unique)
>> +{
>> +	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, true))
>> +		return -EBUSY;
>> +
>> +	if (__netdev_find_upper(dev, upper_dev))
>> +		return -EEXIST;
>> +
>> +	if (unique && netdev_unique_upper_dev_get(dev))
>> +		return -EBUSY;
>> +
>> +	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
>> +	if (!upper)
>> +		return -ENOMEM;
>> +
>> +	upper->dev = upper_dev;
>> +	upper->unique = unique;
>> +
>> +	/*
>> +	 * Ensure that unique upper link is always the first item in the list.
>> +	 */
>> +	if (unique)
>> +		list_add_rcu(&upper->list, &dev->upper_dev_list);
>> +	else
>> +		list_add_tail_rcu(&upper->list, &dev->upper_dev_list);
>> +	dev_hold(upper_dev);
>
>This behaviour (calling dev_hold()) matches netdev_set_master().  But
>it's oddly asymmetric: generally the administrator can remove either the
>upper device or the lower device (rtnl_link_ops or unbinding a physical
>device) and the upper device driver must then unlink itself from the
>lower device (using a notifier to catch lower device removal).
>
>If the upper device driver fails to unlink when the upper device is
>unregistered, then this extra reference causes netdev_wait_allrefs() to
>hang... is that the intent?  Or should there be a more explicit counter
>and check on unregistration, e.g. WARN_ON(dev->num_lower_devs != 0)?
>

I'm not sure I understand you. I believe that upper device notifier
should take care of the unlink. This behaviour is unchanged by the
patch.



>If it fails to unlink when the lower device is removed, this warning in
>rollback_registered_many() may be triggered:
>
>		/* Notifier chain MUST detach us from master device. */
>		WARN_ON(dev->master);
>
>I think that needs to become WARN_ON(netdev_has_upper_dev(dev)).

Patch 15

>
>> +	return 0;
>> +}
>[...] 
>
>-- 
>Ben Hutchings, Staff Engineer, Solarflare
>Not speaking for my employer; that's the marketing department's job.
>They asked us to note that Solarflare product names are trademarked.
>

Re: [patch net-next 15/16] net: remove usage of dev->master

[Jiri Pirko]

Mon, Aug 13, 2012 at 07:15:31PM CEST, bhutchings@solarflare.com wrote:
>On Mon, 2012-08-13 at 17:27 +0200, Jiri Pirko wrote:
>> Signed-off-by: Jiri Pirko <jiri@resnulli.us>
>> ---
>>  net/core/dev.c |    4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>> 
>> diff --git a/net/core/dev.c b/net/core/dev.c
>> index c0f9adb..8977404 100644
>> --- a/net/core/dev.c
>> +++ b/net/core/dev.c
>> @@ -5461,8 +5461,8 @@ 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);
>
>I think this should be folded into patch 1, since that already ensures
>that any master device is included in the upper device list.

Right, I will squash it into patch 1

>
>Ben.
>
>-- 
>Ben Hutchings, Staff Engineer, Solarflare
>Not speaking for my employer; that's the marketing department's job.
>They asked us to note that Solarflare product names are trademarked.
>

Re: [patch net-next 01/16] net: introduce upper device lists

[Flavio Leitner]

On Mon, 13 Aug 2012 17:27:00 +0200
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 "masters" present.
> 
> 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            |  232 ++++++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 244 insertions(+), 2 deletions(-)
> 
> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
> index a9db4f3..e7a07f8 100644
> --- a/include/linux/netdevice.h
> +++ b/include/linux/netdevice.h
> @@ -1173,6 +1173,8 @@ 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
> @@ -2611,6 +2613,18 @@ 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_unique_upper_dev_get(struct net_device *dev);
> +extern struct net_device *netdev_unique_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_unique_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 1f06df8..68db1ac 100644
> --- a/net/core/dev.c
> +++ b/net/core/dev.c
> @@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void)
>  #endif	/* CONFIG_PROC_FS */
>  
>  
> +struct netdev_upper {
> +	struct net_device *dev;
> +	bool unique;

unique is quite confusing here. I see that it is possible to have 
one unique and many non-unique linked in the list, so maybe rename
to 'main_dev', 'master' or 'principal'...


> +	struct list_head list;
> +	struct rcu_head rcu;
> +};
> +
> +static bool __netdev_has_upper_dev(struct net_device *dev,
> +				   struct net_device *upper_dev,
> +				   bool deep)
> +{
> +	struct netdev_upper *upper;
> +
> +	list_for_each_entry(upper, &dev->upper_dev_list, list) {
> +		if (upper->dev == upper_dev)
> +			return true;
> +		if (deep && __netdev_has_upper_dev(upper->dev, upper_dev, deep))
> +			return true;
> +	}
> +	return false;
> +}
> +
> +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_has_upper_dev(dev, upper_dev, false);
> +}
> +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_unique_upper_dev_get - Get unique upper device
> + * @dev: device
> + *
> + * Find a unique 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_unique_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->unique))
> +		return upper->dev;
> +	return NULL;
> +}
> +EXPORT_SYMBOL(netdev_unique_upper_dev_get);
> +
> +/**
> + * netdev_unique_upper_dev_get_rcu - Get unique upper device
> + * @dev: device
> + *
> + * Find a unique 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_unique_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 (likely(upper->unique))

It will oopses here if 'upper' is NULL (i.e. no upper devices).


> +		return upper->dev;
> +	return NULL;
> +}
> +EXPORT_SYMBOL(netdev_unique_upper_dev_get_rcu);
> +
> +static int __netdev_upper_dev_link(struct net_device *dev,
> +				   struct net_device *upper_dev, bool unique)
> +{
> +	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, true))
> +		return -EBUSY;
> +
> +	if (__netdev_find_upper(dev, upper_dev))
> +		return -EEXIST;

__netdev_has_upper_dev() can go all the way up finding the device and
the __netdev_find_upper() just check the first level.

I think it would be better to use:
__netdev_find_upper_dev(,,deep=true/false)
__netdev_has_upper(,)

thanks,
fbl

> +	if (unique && netdev_unique_upper_dev_get(dev))
> +		return -EBUSY;
> +
> +	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
> +	if (!upper)
> +		return -ENOMEM;
> +
> +	upper->dev = upper_dev;
> +	upper->unique = unique;
> +
> +	/*
> +	 * Ensure that unique upper link is always the first item in the list.
> +	 */
> +	if (unique)
> +		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_unique_upper_dev_link - Add a unique 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 unique upper device can be linked, although other non-unique 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_unique_upper_dev_link(struct net_device *dev,
> +				 struct net_device *upper_dev)
> +{
> +	return __netdev_upper_dev_link(dev, upper_dev, true);
> +}
> +EXPORT_SYMBOL(netdev_unique_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
> @@ -4438,19 +4661,23 @@ 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_unique_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);
> @@ -5999,6 +6226,7 @@ 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);
>  

Re: [patch net-next 03/16] vlan: add link to upper device

[Flavio Leitner]

On Mon, 13 Aug 2012 17:27:02 +0200
Jiri Pirko <jiri@resnulli.us> wrote:

> 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 9096bcb..739665e 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;
                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
see below:

>  
>  	/* 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;
>  
> +upper_dev_unlink:
^^^^^^^^^^^^^^^^^^^
should be out_upper_dev_unlink:

fbl

> +	netdev_upper_dev_unlink(real_dev, dev);
>  out_uninit_applicant:
>  	if (grp->nr_vlan_devs == 0)
>  		vlan_gvrp_uninit_applicant(real_dev);

Re: [patch net-next 03/16] vlan: add link to upper device

[Jiri Pirko]

Mon, Aug 13, 2012 at 09:04:21PM CEST, fbl@redhat.com wrote:
>On Mon, 13 Aug 2012 17:27:02 +0200
>Jiri Pirko <jiri@resnulli.us> wrote:
>
>> 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 9096bcb..739665e 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;
>                ^^^^^^^^^^^^^^^^^^^^^^^^^^^
>see below:
>
>>  
>>  	/* 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;
>>  
>> +upper_dev_unlink:
>^^^^^^^^^^^^^^^^^^^
>should be out_upper_dev_unlink:

fixed.

Thanks!

>
>fbl
>
>> +	netdev_upper_dev_unlink(real_dev, dev);
>>  out_uninit_applicant:
>>  	if (grp->nr_vlan_devs == 0)
>>  		vlan_gvrp_uninit_applicant(real_dev);
>

Re: [patch net-next 01/16] net: introduce upper device lists

[Cong Wang]

On 08/13/2012 11:27 PM, 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 "masters" present.
>
> New upper device list resolves this limitation. Also, the information
> stored in lists is used for preventing looping setups like
> "bond->somethingelse->samebond"

Hi, Jiri,

I have some difficulty to understand this patch description, so take 
bridged bonding as an example, IIUC, both the bridge dev and bonding dev 
will be in the upper dev list of eth0 and eth1? And br0 will be in the 
upper dev list of bond0 too?

I think it would be nice to describe the hierarchy after your patches.

Thanks!

Re: [patch net-next 01/16] net: introduce upper device lists

[Jiri Pirko]

Tue, Aug 14, 2012 at 11:02:33AM CEST, xiyou.wangcong@gmail.com wrote:
>On 08/13/2012 11:27 PM, 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 "masters" present.
>>
>>New upper device list resolves this limitation. Also, the information
>>stored in lists is used for preventing looping setups like
>>"bond->somethingelse->samebond"
>
>Hi, Jiri,
>
>I have some difficulty to understand this patch description, so take
>bridged bonding as an example, IIUC, both the bridge dev and bonding
>dev will be in the upper dev list of eth0 and eth1? And br0 will be
>in the upper dev list of bond0 too?

No. Only direct upper device is in the list.

>
>I think it would be nice to describe the hierarchy after your patches.

Hierarchy is the same after.

>
>Thanks!
>

Re: [patch net-next 01/16] net: introduce upper device lists

[Jiri Pirko]

Mon, Aug 13, 2012 at 07:52:17PM CEST, fbl@redhat.com wrote:
>On Mon, 13 Aug 2012 17:27:00 +0200
>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 "masters" present.
>> 
>> 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            |  232 ++++++++++++++++++++++++++++++++++++++++++++-
>>  2 files changed, 244 insertions(+), 2 deletions(-)
>> 
>> diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
>> index a9db4f3..e7a07f8 100644
>> --- a/include/linux/netdevice.h
>> +++ b/include/linux/netdevice.h
>> @@ -1173,6 +1173,8 @@ 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
>> @@ -2611,6 +2613,18 @@ 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_unique_upper_dev_get(struct net_device *dev);
>> +extern struct net_device *netdev_unique_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_unique_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 1f06df8..68db1ac 100644
>> --- a/net/core/dev.c
>> +++ b/net/core/dev.c
>> @@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void)
>>  #endif	/* CONFIG_PROC_FS */
>>  
>>  
>> +struct netdev_upper {
>> +	struct net_device *dev;
>> +	bool unique;
>
>unique is quite confusing here. I see that it is possible to have 
>one unique and many non-unique linked in the list, so maybe rename
>to 'main_dev', 'master' or 'principal'...
>
>
>> +	struct list_head list;
>> +	struct rcu_head rcu;
>> +};
>> +
>> +static bool __netdev_has_upper_dev(struct net_device *dev,
>> +				   struct net_device *upper_dev,
>> +				   bool deep)
>> +{
>> +	struct netdev_upper *upper;
>> +
>> +	list_for_each_entry(upper, &dev->upper_dev_list, list) {
>> +		if (upper->dev == upper_dev)
>> +			return true;
>> +		if (deep && __netdev_has_upper_dev(upper->dev, upper_dev, deep))
>> +			return true;
>> +	}
>> +	return false;
>> +}
>> +
>> +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_has_upper_dev(dev, upper_dev, false);
>> +}
>> +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_unique_upper_dev_get - Get unique upper device
>> + * @dev: device
>> + *
>> + * Find a unique 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_unique_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->unique))
>> +		return upper->dev;
>> +	return NULL;
>> +}
>> +EXPORT_SYMBOL(netdev_unique_upper_dev_get);
>> +
>> +/**
>> + * netdev_unique_upper_dev_get_rcu - Get unique upper device
>> + * @dev: device
>> + *
>> + * Find a unique 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_unique_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 (likely(upper->unique))
>
>It will oopses here if 'upper' is NULL (i.e. no upper devices).


Fixed

>
>
>> +		return upper->dev;
>> +	return NULL;
>> +}
>> +EXPORT_SYMBOL(netdev_unique_upper_dev_get_rcu);
>> +
>> +static int __netdev_upper_dev_link(struct net_device *dev,
>> +				   struct net_device *upper_dev, bool unique)
>> +{
>> +	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, true))
>> +		return -EBUSY;
>> +
>> +	if (__netdev_find_upper(dev, upper_dev))
>> +		return -EEXIST;
>
>__netdev_has_upper_dev() can go all the way up finding the device and
>the __netdev_find_upper() just check the first level.


I do not think this ordering is somewhat inportant.

>
>I think it would be better to use:
>__netdev_find_upper_dev(,,deep=true/false)
>__netdev_has_upper(,)
>
>thanks,
>fbl
>
>> +	if (unique && netdev_unique_upper_dev_get(dev))
>> +		return -EBUSY;
>> +
>> +	upper = kmalloc(sizeof(*upper), GFP_KERNEL);
>> +	if (!upper)
>> +		return -ENOMEM;
>> +
>> +	upper->dev = upper_dev;
>> +	upper->unique = unique;
>> +
>> +	/*
>> +	 * Ensure that unique upper link is always the first item in the list.
>> +	 */
>> +	if (unique)
>> +		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_unique_upper_dev_link - Add a unique 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 unique upper device can be linked, although other non-unique 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_unique_upper_dev_link(struct net_device *dev,
>> +				 struct net_device *upper_dev)
>> +{
>> +	return __netdev_upper_dev_link(dev, upper_dev, true);
>> +}
>> +EXPORT_SYMBOL(netdev_unique_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
>> @@ -4438,19 +4661,23 @@ 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_unique_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);
>> @@ -5999,6 +6226,7 @@ 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);
>>  
>

Re: [patch net-next 01/16] net: introduce upper device lists

[Flavio Leitner]

On Tue, 14 Aug 2012 14:24:33 +0200
Jiri Pirko <jiri@resnulli.us> wrote:

> Mon, Aug 13, 2012 at 07:52:17PM CEST, fbl@redhat.com wrote:
> >On Mon, 13 Aug 2012 17:27:00 +0200
> >Jiri Pirko <jiri@resnulli.us> wrote:
> >> +	/*
> >> +	 * To prevent loops, check if dev is not upper device to upper_dev.
> >> +	 */
> >> +	if (__netdev_has_upper_dev(upper_dev, dev, true))
> >> +		return -EBUSY;
> >> +
> >> +	if (__netdev_find_upper(dev, upper_dev))
> >> +		return -EEXIST;
> >
> >__netdev_has_upper_dev() can go all the way up finding the device and
> >the __netdev_find_upper() just check the first level.
> 
> 
> I do not think this ordering is somewhat inportant.

it's not the order, see below:

> >I think it would be better to use:
> >__netdev_find_upper_dev(,,deep=true/false)
> >__netdev_has_upper(,)

It's their names.  Currently, the function ..._find_... look at
one level only, while the function ..._has_... does one or more
levels.  I think it's better to swap 'has' and 'find' in their names:

__netdev_find_upper_dev(,,deep=true/false) <-- find in all levels
__netdev_has_upper(,)  <-- check only the one level.

fbl

Re: [patch net-next 01/16] net: introduce upper device lists

[Jiri Pirko]

Tue, Aug 14, 2012 at 03:14:00PM CEST, fbl@redhat.com wrote:
>On Tue, 14 Aug 2012 14:24:33 +0200
>Jiri Pirko <jiri@resnulli.us> wrote:
>
>> Mon, Aug 13, 2012 at 07:52:17PM CEST, fbl@redhat.com wrote:
>> >On Mon, 13 Aug 2012 17:27:00 +0200
>> >Jiri Pirko <jiri@resnulli.us> wrote:
>> >> +	/*
>> >> +	 * To prevent loops, check if dev is not upper device to upper_dev.
>> >> +	 */
>> >> +	if (__netdev_has_upper_dev(upper_dev, dev, true))
>> >> +		return -EBUSY;
>> >> +
>> >> +	if (__netdev_find_upper(dev, upper_dev))
>> >> +		return -EEXIST;
>> >
>> >__netdev_has_upper_dev() can go all the way up finding the device and
>> >the __netdev_find_upper() just check the first level.
>> 
>> 
>> I do not think this ordering is somewhat inportant.
>
>it's not the order, see below:
>
>> >I think it would be better to use:
>> >__netdev_find_upper_dev(,,deep=true/false)
>> >__netdev_has_upper(,)
>
>It's their names.  Currently, the function ..._find_... look at
>one level only, while the function ..._has_... does one or more
>levels.  I think it's better to swap 'has' and 'find' in their names:
>
>__netdev_find_upper_dev(,,deep=true/false) <-- find in all levels
>__netdev_has_upper(,)  <-- check only the one level.

Oh, now I think I see your point. But realise this:

The main reason for __netdev_find_upper() is to find "struct upper" for
netdev_upper_dev_unlink(). Therefore the name is not
"__netdev_find_upper_dev" and there's no need to go deep here.

On the orher hand, __netdev_has_upper_dev() only says whether device is lower
to specified upper device. In this case I think the name is quite
convenient as well.


>
>fbl

Re: [patch net-next 01/16] net: introduce upper device lists

[Nicolas de Pesloüan]

Le 13/08/2012 19:31, Jiri Pirko a écrit :
> Mon, Aug 13, 2012 at 07:04:11PM CEST, bhutchings@solarflare.com wrote:

>>> +struct netdev_upper {
>>> +	struct net_device *dev;
>>> +	bool unique;
>>
>> This needs a better name.  It doesn't really have anything to do with
>> uniqueness and doesn't ensure exclusivity.  I think that it would be
>> fine to keep the 'master' term.
>
> Hmm. I admit that "unique" I do not like too much as well. But "master"
> I like even less.
>
> This flag should ensure exclusivity. Only one upper device with this
> flag can be present at a time.

Well, can't we simply call it "upper_device"?

And as we only have a single field, this is exclusive by design.

	Nicolas.