Re: [PATCH net v3 09/11] net: core: add ignore flag to netdev_adjacent structure
From: Jakub Kicinski <hidden>
Date: 2019-09-20 23:55:13
On Mon, 16 Sep 2019 22:48:00 +0900, Taehee Yoo wrote:
In order to link an adjacent node, netdev_upper_dev_link() is used and in order to unlink an adjacent node, netdev_upper_dev_unlink() is used. unlink operation does not fail, but link operation can fail. In order to exchange adjacent nodes, we should unlink an old adjacent node first. then, link a new adjacent node. If link operation is failed, we should link an old adjacent node again. But this link operation can fail too. It eventually breaks the adjacent link relationship. This patch adds an ignore flag into the netdev_adjacent structure. If this flag is set, netdev_upper_dev_link() ignores an old adjacent node for a moment. So we can skip unlink operation before link operation. Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Could this perhaps be achieved by creating prepare, commit, and abort helpers? That would make the API look slightly more canonical. netdev_adjacent_change_prepare(old, new, dev) netdev_adjacent_change_commit(old, new, dev) netdev_adjacent_change_abort(old, new, dev) The current naming makes the operation a little harder to follow if one is just reading the vxlan code. Please let me know if I didn't read the code closely enough to understand why that's not fitting here.
quoted hunk ↗ jump to hunk
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 5bb5756129af..4506810c301b 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h@@ -4319,6 +4319,10 @@ int netdev_master_upper_dev_link(struct net_device *dev, struct netlink_ext_ack *extack); void netdev_upper_dev_unlink(struct net_device *dev, struct net_device *upper_dev); +void netdev_adjacent_dev_disable(struct net_device *upper_dev, + struct net_device *lower_dev); +void netdev_adjacent_dev_enable(struct net_device *upper_dev, + struct net_device *lower_dev); void netdev_adjacent_rename_links(struct net_device *dev, char *oldname); void *netdev_lower_dev_get_private(struct net_device *dev, struct net_device *lower_dev);