1.\" 2.\" SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3.\" 4.\" Copyright (c) 2021 The FreeBSD Foundation 5.\" 6.\" This manual page was written by Ka Ho Ng under sponsorship from 7.\" the FreeBSD Foundation. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.Dd Jul 30, 2021 31.Dt VN_DEALLOCATE 9 32.Os 33.Sh NAME 34.Nm vn_deallocate 35.Nd zero and/or deallocate storage from a file 36.Sh SYNOPSIS 37.In sys/param.h 38.In sys/vnode.h 39.Ft int 40.Fo vn_deallocate 41.Fa "struct vnode *vp" 42.Fa "off_t *offset" 43.Fa "off_t *length" 44.Fa "int flags" 45.Fa "int ioflg" 46.Fa "struct ucred *active_cred" 47.Fa "struct ucred *file_cred" 48.Fc 49.Sh DESCRIPTION 50The 51.Fn vn_deallocate 52function zeros and/or deallocates backing storage space from a file. 53This function only works on vnodes with 54.Dv VREG 55type. 56.Pp 57The arguments are: 58.Bl -tag -width active_cred 59.It Fa vp 60The vnode of the file. 61.It Fa offset 62The starting offset of the operation range. 63.It Fa length 64The length of the operation range. 65This must be greater than 0. 66.It Fa flags 67The control flags of the operation. 68This should be set to 0 for now. 69.It Fa ioflg 70The control flags of vnode locking. 71.It Fa active_cred 72The user credentials of the calling thread. 73.It Fa file_cred 74The credentials installed on the file description pointing to the vnode or NOCRED. 75.El 76.Pp 77The 78.Fn ioflg 79argument may be one or more of the following flags: 80.Bl -tag -width IO_RANGELOCKED 81.It Dv IO_NODELOCKED 82The vnode was locked before the call. 83.It Dv IO_RANGELOCKED 84Rangelock was owned around the call. 85.It Dv IO_NOMACCHECK 86Skip MAC checking in the call. 87.El 88.Pp 89.Fa *offset 90and 91.Fa *length 92are updated to reflect the unprocessed operation range of the call. 93.Sh RETURN VALUES 94Upon successful completion, the value 0 is returned; otherwise the 95appropriate error is returned. 96.Sh SEE ALSO 97.Xr vnode 9 , 98.Xr VOP_DEALLOCATE 9 99.Sh AUTHORS 100.Nm 101and this manual page was written by 102.An Ka Ho Ng Aq Mt khng@FreeBSD.org 103under sponsorship from the FreeBSD Foundation. 104