Add event handlers for module load and unload events. The load handlers are

called after the module has been loaded, and the unload handlers are called
before the module is unloaded. Moreover, the module unload handlers may
return an error to prevent the unload from proceeding.

Reviewed by:	avg
MFC after:	2 weeks

1 files changed, 7 insertions, 1 deletions

diff --git a/share/man/man9/EVENTHANDLER.9 b/share/man/man9/EVENTHANDLER.9
index 4a1666087c9b..ee015cd7909e 100644
--- a/share/man/man9/EVENTHANDLER.9
+++ b/share/man/man9/EVENTHANDLER.9
@@ -23,7 +23,7 @@
 .\" SUCH DAMAGE.
 .\" $FreeBSD$
 .\"
-.Dd May 11, 2012
+.Dd August 1, 2013
 .Dt EVENTHANDLER 9
 .Os
 .Sh NAME
@@ -199,6 +199,12 @@ Callbacks invoked when a new network interface appears.
 Callbacks invoked when a network interface is taken down.
 .It Vt bpf_track
 Callbacks invoked when a BPF listener attaches to/detaches from network interface.
+.It Vt mod_load
+Callbacks invoked after a module has been loaded.
+.It Vt mod_unload
+Callbacks invoked before a module is about to be unloaded.
+These callbacks may be used to return an error and prevent the unload from
+proceeding.
 .It Vt power_profile_change
 Callbacks invoked when the power profile of the system changes.
 .It Vt process_exec