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 August 25, 2021 31.Dt VOP_DEALLOCATE 9 32.Os 33.Sh NAME 34.Nm VOP_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 VOP_DEALLOCATE 41.Fa "struct vnode *vp" 42.Fa "off_t *offset" 43.Fa "off_t *len" 44.Fa "int flags" 45.Fa "int ioflag" 46.Fa "struct ucred *cred" 47.Fc 48.Sh DESCRIPTION 49This VOP call zeroes/deallocates storage for an offset range in a file. 50It is used to implement the 51.Xr fspacectl 2 52system call. 53.Pp 54Its arguments are: 55.Bl -tag -width offset 56.It Fa vp 57The vnode of the file. 58.It Fa offset 59The start of the range to deallocate storage in the file. 60.It Fa len 61The length of the range to deallocate storage in the file. 62.It Fa flags 63The flags of this call. 64This should be set to 0 for now. 65.It Fa ioflag 66Directives and hints to be given to the file system. 67.It Fa cred 68The credentials of the caller. 69.El 70.Pp 71.Fa *offset 72and 73.Fa *len 74are updated to reflect the portion of the range that 75still needs to be zeroed/deallocated on return. 76Partial result is considered a successful operation. 77For a non-partial successful completion, 78.Fa *len 79is updated to be the value 0, and 80.Fa *offset 81is incremented by the number of bytes zeroed before the end-of-file. 82.Sh LOCKS 83The vnode should be locked on entry and will still be locked on exit. 84.Sh RETURN VALUES 85Zero is returned if the call is successful, otherwise an appropriate 86error code is returned. 87.Sh ERRORS 88.Bl -tag -width Er 89.It Bq Er EINVAL 90Invalid 91.Fa offset , len 92or 93.Fa flags 94parameters are passed into this VOP call. 95.It Bq Er ENODEV 96The vnode type is not supported by this VOP call. 97.It Bq Er ENOSPC 98The file system is full. 99.It Bq Er EPERM 100An append-only flag is set on the file, but the caller is attempting to 101zero before the current end of file. 102.El 103.Sh SEE ALSO 104.Xr vnode 9 105.Sh AUTHORS 106.Nm 107and this manual page was written by 108.An Ka Ho Ng Aq Mt khng@FreeBSD.org 109under sponsorship from the FreeBSD Foundation. 110