1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as 9.\" the first lines of this file unmodified other than the possible 10.\" addition of one or more copyright notices. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice(s), this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY 16.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" 27.\" $FreeBSD$ 28.\" 29.Dd November 2, 2008 30.Dt VFS_BUSY 9 31.Os 32.Sh NAME 33.Nm vfs_busy 34.Nd "marks a mount point as busy" 35.Sh SYNOPSIS 36.In sys/param.h 37.In sys/mount.h 38.Ft int 39.Fn vfs_busy "struct mount *mp" "int flags" 40.Sh DESCRIPTION 41The 42.Fn vfs_busy 43function marks a mount point as busy. 44The purpose of this 45function is to synchronize access to a mount point. 46It also delays unmounting by sleeping on 47.Fa mp 48if the 49.Dv MNTK_UNMOUNT 50flag is set in 51.Fa mp->mnt_kern_flag 52and the 53.Dv LK_NOWAIT 54flag is 55.Em not 56set. 57.Pp 58Its arguments are: 59.Bl -tag -width ".Fa flags" 60.It Fa mp 61The mount point to busy. 62.It Fa flags 63Flags controlling how 64.Fn vfs_busy 65should act. 66.Bl -tag -width ".Dv MBF_MNTLSTLOCK" 67.It Dv MBF_NOWAIT 68do not sleep if 69.Dv MNTK_UNMOUNT 70is set. 71.It Dv MBF_MNTLSTLOCK 72drop the mountlist_mtx in the critical path. 73.El 74.El 75.Sh RETURN VALUES 76A 0 value is returned on success. 77If the mount point is being 78unmounted 79.Er ENOENT 80will always be returned. 81.Sh ERRORS 82.Bl -tag -width Er 83.It Bq Er ENOENT 84The mount point is being unmounted 85.Dv ( MNTK_UNMOUNT 86is set). 87.El 88.Sh AUTHORS 89This manual page was written by 90.An Chad David Aq davidc@acns.ab.ca . 91