diff options
Diffstat (limited to 'Documentation/networking/operstates.txt')
| -rw-r--r-- | Documentation/networking/operstates.txt | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/Documentation/networking/operstates.txt b/Documentation/networking/operstates.txt index 355c6d8ef8ad..b203d1334822 100644 --- a/Documentation/networking/operstates.txt +++ b/Documentation/networking/operstates.txt @@ -22,8 +22,9 @@ 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. It is also possible to subscribe to RTNLGRP_LINK +to be notified of updates while the interface is admin up. This is +important for setting from userspace. These values contain interface state: @@ -101,8 +102,9 @@ because some driver controlled protocol establishment has to 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(). +On device allocation, both flags __LINK_STATE_NOCARRIER and +__LINK_STATE_DORMANT are cleared, so the effective state is equivalent +to netif_carrier_ok() and !netif_dormant(). Whenever the driver CHANGES one of these flags, a workqueue event is @@ -133,11 +135,11 @@ 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 |