netpoll: add generic support for bridge and bonding devices

This whole patchset is for adding netpoll support to bridge and bonding
devices. I already tested it for bridge, bonding, bridge over bonding,
and bonding over bridge. It looks fine now.

To make bridge and bonding support netpoll, we need to adjust
some netpoll generic code. This patch does the following things:

1) introduce two new priv_flags for struct net_device:
   IFF_IN_NETPOLL which identifies we are processing a netpoll;
   IFF_DISABLE_NETPOLL is used to disable netpoll support for a device
   at run-time;

2) introduce one new method for netdev_ops:
   ->ndo_netpoll_cleanup() is used to clean up netpoll when a device is
     removed.

3) introduce netpoll_poll_dev() which takes a struct net_device * parameter;
   export netpoll_send_skb() and netpoll_poll_dev() which will be used later;

4) hide a pointer to struct netpoll in struct netpoll_info, ditto.

5) introduce ->real_dev for struct netpoll.

6) introduce a new status NETDEV_BONDING_DESLAE, which is used to disable
   netconsole before releasing a slave, to avoid deadlocks.

Cc: David Miller <davem@davemloft.net>
Cc: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: WANG Cong <amwang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/if.h b/include/linux/if.h
index 3a9f410a296b..be350e62a905 100644
--- a/include/linux/if.h
+++ b/include/linux/if.h
@@ -71,6 +71,8 @@
                                          * release skb->dst
                                          */
 #define IFF_DONT_BRIDGE 0x800           /* disallow bridging this ether dev */
+#define IFF_IN_NETPOLL  0x1000          /* whether we are processing netpoll */
+#define IFF_DISABLE_NETPOLL     0x2000  /* disable netpoll at run-time */
 
 #define IF_GET_IFACE    0x0001          /* for querying only */
 #define IF_GET_PROTO    0x0002