net: dev: Add NETDEV_PRE_CHANGEADDR (1570415f) · Commits · 戴 / test

The NETDEV_CHANGEADDR notification is emitted after a device address changes. Extending this message to allow vetoing is certainly possible, but several other notification types have instead adopted a simple two-stage approach: first a "pre" notification is sent to make sure all interested parties are OK with a change that's about to be done. Then the change is done, and afterwards a "post" notification is sent. This dual approach is easier to use: when the change is vetoed, nothing has changed yet, and it's therefore unnecessary to roll anything back. Therefore adopt it for NETDEV_CHANGEADDR as well. To that end, add NETDEV_PRE_CHANGEADDR and an info structure to go along with it. Signed-off-by:

Petr Machata <petrm@mellanox.com> Acked-by:

Jiri Pirko <jiri@mellanox.com> Reviewed-by:

Ido Schimmel <idosch@mellanox.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

+7 −1

Original line number	Diff line number	Diff line
		@@ -2450,7 +2450,8 @@ enum netdev_cmd {
		NETDEV_REGISTER,
		NETDEV_UNREGISTER,
		NETDEV_CHANGEMTU, /* notify after mtu change happened */
		NETDEV_CHANGEADDR,
		NETDEV_CHANGEADDR, /* notify after the address change */
		NETDEV_PRE_CHANGEADDR, /* notify before the address change */
		NETDEV_GOING_DOWN,
		NETDEV_CHANGENAME,
		NETDEV_FEAT_CHANGE,
		@@ -2512,6 +2513,11 @@ struct netdev_notifier_changelowerstate_info {
		void lower_state_info; / is lower dev state */
		};

		struct netdev_notifier_pre_changeaddr_info {
		struct netdev_notifier_info info; /* must be first */
		const unsigned char *dev_addr;
		};

		static inline void netdev_notifier_info_init(struct netdev_notifier_info *info,
		struct net_device *dev)
		{

net/core/dev.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1589,6 +1589,7 @@ const char *netdev_cmd_to_name(enum netdev_cmd cmd)
		N(UDP_TUNNEL_DROP_INFO) N(CHANGE_TX_QUEUE_LEN)
		N(CVLAN_FILTER_PUSH_INFO) N(CVLAN_FILTER_DROP_INFO)
		N(SVLAN_FILTER_PUSH_INFO) N(SVLAN_FILTER_DROP_INFO)
		N(PRE_CHANGEADDR)
		}
		#undef N
		return "UNKNOWN_NETDEV_EVENT";

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