diff --git a/share/man/man9/dev_clone.9 b/share/man/man9/dev_clone.9 new file mode 100644 index 000000000000..ce3774accb1b --- /dev/null +++ b/share/man/man9/dev_clone.9 @@ -0,0 +1,74 @@ +.\" Copyright (c) 2008 Konstantin Belousov +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd September 8, 2008 +.Sh NAME +.Nm dev_clone , +.Nm drain_dev_clone_events +.Nd eventhandler for name-based device cloning in devfs +.Sh SYNOPSIS +.In sys/param.h +.In sys/conf.h +.Ft void +.Fn clone_handler "void *arg" "struct ucred *cr" "char *name" "int namelen" "struct cdev **dev" +.Bd -literal +EVENTHANDLER_REGISTER(dev_clone, clone_handler, arg, priority); +.Ed +.Ft void +.Fn drain_dev_clone_events +.Sh DESCRIPTION +Device driver may register a listener that will be notified each time +name lookup on the +.Xr devfs +mount point fails to find the vnode. +Listener shall be registered for the +.Va dev_clone +event. +When called, it is supplied with the first argument +.Va arg +that was specified at handler registration time, +appropriate credentials +.Va cr , +.Va name +of the length +.Va namelen +that was looked for. +If handler decides that the name is appropriate and want to create device +that will be associated with the name, it should return it to the devfs +in the +.Va dev . +.Pp +The +.Fn drain_dev_clone_events +function is a barrier. +It is guaranteed that all calls to eventhandlers for dev_clone that were +started before +.Fn drain_dev_clone_events +call, are finished before it returns control. +.Pp +.Sh SEE ALSO +.Xr devfs 5 , +.Xr namei 9