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 February 11, 2013 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 by incrementing 44the reference count of a mount point. 45It also delays unmounting by sleeping on 46.Fa mp 47if the 48.Dv MNTK_UNMOUNT 49flag is set in 50.Fa mp->mnt_kern_flag 51and the 52.Dv MBF_NOWAIT 53flag is 54.Em not 55set. 56.Pp 57Its arguments are: 58.Bl -tag -width ".Fa flags" 59.It Fa mp 60The mount point to busy. 61.It Fa flags 62Flags controlling how 63.Fn vfs_busy 64should act. 65.Bl -tag -width ".Dv MBF_MNTLSTLOCK" 66.It Dv MBF_NOWAIT 67do not sleep if 68.Dv MNTK_UNMOUNT 69is set. 70.It Dv MBF_MNTLSTLOCK 71drop the mountlist_mtx in the critical path. 72.El 73.El 74.Sh RETURN VALUES 75A 0 value is returned on success. 76If the mount point is being 77unmounted and MBF_NOWAIT flag is specified 78.Er ENOENT 79will be returned. 80.Sh ERRORS 81.Bl -tag -width Er 82.It Bq Er ENOENT 83The mount point is being unmounted 84.Dv ( MNTK_UNMOUNT 85is set). 86.El 87.Sh SEE ALSO 88.Xr vfs_unbusy 9 89.Sh AUTHORS 90This manual page was written by 91.An Chad David Aq Mt davidc@acns.ab.ca . 92