[<prev] [next>] [day] [month] [year] [list]
Message-ID: <20181201160059.GA5175@Mindship-05.localdomain>
Date: Sat, 1 Dec 2018 17:00:59 +0100
From: Jouke Witteveen <j.witteveen@...il.com>
To: davem@...emloft.net
Cc: netdev@...r.kernel.org
Subject: [PATCH 2/2] Documentation: bring operstate documentation up-to-date
Signed-off-by: Jouke Witteveen <j.witteveen@...il.com>
---
Documentation/networking/operstates.txt | 13 ++++++++-----
net/sched/sch_generic.c | 2 +-
2 files changed, 9 insertions(+), 6 deletions(-)
diff --git a/Documentation/networking/operstates.txt b/Documentation/networking/operstates.txt
index 355c6d8ef..8f1c4ff79 100644
--- a/Documentation/networking/operstates.txt
+++ b/Documentation/networking/operstates.txt
@@ -22,8 +22,11 @@ and changeable from userspace under certain rules.
2. Querying from userspace
Both admin and operational state can be queried via the netlink
-operation RTM_GETLINK. It is also possible to subscribe to RTMGRP_LINK
-to be notified of updates. This is important for setting from userspace.
+operation RTM_GETLINK. This is important for setting from userspace.
+It is also possible to be notified of updates to the operational state
+as long as the interface is admin up. For this, either subscribe to
+the netlink multicast group RTNLGRP_LINK, or listen for "change"
+uevents on the device.
These values contain interface state:
@@ -102,7 +105,7 @@ complete. Corresponding functions are netif_dormant_on() to set the
flag, netif_dormant_off() to clear it and netif_dormant() to query.
On device allocation, networking core sets the flags equivalent to
-netif_carrier_ok() and !netif_dormant().
+!netif_carrier_ok() and netif_dormant().
Whenever the driver CHANGES one of these flags, a workqueue event is
@@ -133,11 +136,11 @@ netif_carrier_ok() && !netif_dormant() is set by the
driver. Afterwards, the userspace application can set IFLA_OPERSTATE
to IF_OPER_DORMANT or IF_OPER_UP as long as the driver does not set
netif_carrier_off() or netif_dormant_on(). Changes made by userspace
-are multicasted on the netlink group RTMGRP_LINK.
+are multicasted on the netlink group RTNLGRP_LINK.
So basically a 802.1X supplicant interacts with the kernel like this:
--subscribe to RTMGRP_LINK
+-subscribe to RTNLGRP_LINK
-set IFLA_LINKMODE to 1 via RTM_SETLINK
-query RTM_GETLINK once to get initial state
-if initial flags are not (IFF_LOWER_UP && !IFF_DORMANT), wait until
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index de1663f7d..3a59e440f 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -500,7 +500,7 @@ static void dev_watchdog_down(struct net_device *dev)
* netif_carrier_on - set carrier
* @dev: network device
*
- * Device has detected that carrier.
+ * Device has detected acquisition of carrier.
*/
void netif_carrier_on(struct net_device *dev)
{
--
2.19.2
Powered by blists - more mailing lists