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.Dd February 11, 2013 28.Dt VFS_BUSY 9 29.Os 30.Sh NAME 31.Nm vfs_busy 32.Nd "marks a mount point as busy" 33.Sh SYNOPSIS 34.In sys/param.h 35.In sys/mount.h 36.Ft int 37.Fn vfs_busy "struct mount *mp" "int flags" 38.Sh DESCRIPTION 39The 40.Fn vfs_busy 41function marks a mount point as busy by incrementing 42the reference count of a mount point. 43It also delays unmounting by sleeping on 44.Fa mp 45if the 46.Dv MNTK_UNMOUNT 47flag is set in 48.Fa mp->mnt_kern_flag 49and the 50.Dv MBF_NOWAIT 51flag is 52.Em not 53set. 54.Pp 55Its arguments are: 56.Bl -tag -width ".Fa flags" 57.It Fa mp 58The mount point to busy. 59.It Fa flags 60Flags controlling how 61.Fn vfs_busy 62should act. 63.Bl -tag -width ".Dv MBF_MNTLSTLOCK" 64.It Dv MBF_NOWAIT 65do not sleep if 66.Dv MNTK_UNMOUNT 67is set. 68.It Dv MBF_MNTLSTLOCK 69drop the mountlist_mtx in the critical path. 70.El 71.El 72.Sh RETURN VALUES 73A 0 value is returned on success. 74If the mount point is being 75unmounted and MBF_NOWAIT flag is specified 76.Er ENOENT 77will be returned. 78.Sh ERRORS 79.Bl -tag -width Er 80.It Bq Er ENOENT 81The mount point is being unmounted 82.Dv ( MNTK_UNMOUNT 83is set). 84.El 85.Sh SEE ALSO 86.Xr vfs_unbusy 9 87.Sh AUTHORS 88This manual page was written by 89.An Chad David Aq Mt davidc@acns.ab.ca . 90