18981fef8SAlfred Perlstein.\" 28981fef8SAlfred Perlstein.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 38981fef8SAlfred Perlstein.\" 48981fef8SAlfred Perlstein.\" Redistribution and use in source and binary forms, with or without 58981fef8SAlfred Perlstein.\" modification, are permitted provided that the following conditions 68981fef8SAlfred Perlstein.\" are met: 78981fef8SAlfred Perlstein.\" 1. Redistributions of source code must retain the above copyright 88981fef8SAlfred Perlstein.\" notice(s), this list of conditions and the following disclaimer as 98981fef8SAlfred Perlstein.\" the first lines of this file unmodified other than the possible 108981fef8SAlfred Perlstein.\" addition of one or more copyright notices. 118981fef8SAlfred Perlstein.\" 2. Redistributions in binary form must reproduce the above copyright 128981fef8SAlfred Perlstein.\" notice(s), this list of conditions and the following disclaimer in the 138981fef8SAlfred Perlstein.\" documentation and/or other materials provided with the distribution. 148981fef8SAlfred Perlstein.\" 158981fef8SAlfred Perlstein.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY 168981fef8SAlfred Perlstein.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 178981fef8SAlfred Perlstein.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 188981fef8SAlfred Perlstein.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY 198981fef8SAlfred Perlstein.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 208981fef8SAlfred Perlstein.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 218981fef8SAlfred Perlstein.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 228981fef8SAlfred Perlstein.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 238981fef8SAlfred Perlstein.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 248981fef8SAlfred Perlstein.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 258981fef8SAlfred Perlstein.\" DAMAGE. 268981fef8SAlfred Perlstein.\" 278981fef8SAlfred Perlstein.\" $FreeBSD$ 288981fef8SAlfred Perlstein.\" 298981fef8SAlfred Perlstein.Dd July 8, 2001 308981fef8SAlfred Perlstein.Dt VFS_BUSY 9 318981fef8SAlfred Perlstein.Os 328981fef8SAlfred Perlstein.Sh NAME 338981fef8SAlfred Perlstein.Nm vfs_busy 3423789024SRuslan Ermilov.Nd "marks a mount point as busy" 358981fef8SAlfred Perlstein.Sh SYNOPSIS 3623789024SRuslan Ermilov.In sys/param.h 3723789024SRuslan Ermilov.In sys/mount.h 388981fef8SAlfred Perlstein.Ft int 390ef36920SAlfred Perlstein.Fn vfs_busy "struct mount *mp" "int flags" "struct mtx *interlkp" "struct proc *p" 408981fef8SAlfred Perlstein.Sh DESCRIPTION 418981fef8SAlfred PerlsteinThe 4223789024SRuslan Ermilov.Fn vfs_busy 4323789024SRuslan Ermilovfunction marks a mount point as busy. 4423789024SRuslan ErmilovThe purpose of this 4523789024SRuslan Ermilovfunction is to synchronize access to a mount point. 4623789024SRuslan ErmilovIt also delays unmounting by sleeping on mp if the 4723789024SRuslan Ermilov.Dv MNTK_UNMOUNT 4823789024SRuslan Ermilovflag is set in 4923789024SRuslan Ermilov.Fa mp->mnt_kern_flag 5023789024SRuslan Ermilovand the 5123789024SRuslan Ermilov.Dv LK_NOWAIT 5223789024SRuslan Ermilovflag is 5323789024SRuslan Ermilov.Em not 5423789024SRuslan Ermilovset. 558981fef8SAlfred Perlstein.Pp 568981fef8SAlfred PerlsteinIts arguments are: 5723789024SRuslan Ermilov.Bl -tag -xwidth ".Fa interlkp" 5823789024SRuslan Ermilov.It Fa mp 598981fef8SAlfred PerlsteinThe mount point to busy. 6023789024SRuslan Ermilov.It Fa flags 618981fef8SAlfred PerlsteinFlags controlling the operation of 6223789024SRuslan Ermilov.Fn vfs_busy . 6323789024SRuslan Ermilov.Bl -tag -xwidth ".Dv LK_NOWAIT" 6423789024SRuslan Ermilov.It Dv LK_NOWAIT 6523789024SRuslan Ermilovdo not sleep if 6623789024SRuslan Ermilov.Dv MNTK_UNMOUNT 6723789024SRuslan Ermilovis set. 6823789024SRuslan Ermilov.El 6923789024SRuslan Ermilov.It Fa interlkp 7023789024SRuslan ErmilovThe interlock mutex for 7123789024SRuslan Ermilov.Fa mp->mount_lock . 7223789024SRuslan ErmilovIf there is any chance 7323789024SRuslan Ermilovthe mount point is being unmounted and 7423789024SRuslan Ermilov.Dv LK_NOWAIT 7523789024SRuslan Ermilovis not set then 768981fef8SAlfred Perlsteininterlock must be valid locked mutex. 7723789024SRuslan Ermilov.It Fa p 788981fef8SAlfred PerlsteinThe process responsible for this call. 798981fef8SAlfred Perlstein.El 808981fef8SAlfred Perlstein.Sh LOCKS 8123789024SRuslan ErmilovIf 8223789024SRuslan Ermilov.Fa interlkp 8323789024SRuslan Ermilovis a valid pointer it must be locked on entry, 848981fef8SAlfred Perlsteinand it will not be unlocked even on error. 858981fef8SAlfred Perlstein.Sh RETURN VALUES 8623789024SRuslan ErmilovA 0 value is returned on success. 8723789024SRuslan ErmilovIf the mount point is being 8823789024SRuslan Ermilovunmounted 8923789024SRuslan Ermilov.Er ENOENT 9023789024SRuslan Ermilovwill always be returned. 918981fef8SAlfred Perlstein.Sh ERRORS 9223789024SRuslan Ermilov.Bl -tag -width Er 9323789024SRuslan Ermilov.It Bq Er ENOENT 9423789024SRuslan ErmilovThe mount point is being unmounted 9523789024SRuslan Ermilov.Dv ( MNTK_UNMOUNT 9623789024SRuslan Ermilovis set). 978981fef8SAlfred Perlstein.El 988981fef8SAlfred Perlstein.Sh AUTHORS 9923789024SRuslan ErmilovThis man page was written by 10023789024SRuslan Ermilov.An Chad David . 101