xref: /freebsd/share/man/man9/VOP_ALLOCATE.9 (revision 064f00ec274fbfdcab19ed8150afb187468a0c4f)
1.\" -*- nroff -*-
2.\"
3.\" Copyright (c) 2013 Hudson River Trading LLC
4.\" Written by: John H. Baldwin <jhb@FreeBSD.org>
5.\" All rights reserved.
6.\"
7.\" Redistribution and use in source and binary forms, with or without
8.\" modification, are permitted provided that the following conditions
9.\" are met:
10.\" 1. Redistributions of source code must retain the above copyright
11.\"    notice, this list of conditions and the following disclaimer.
12.\" 2. Redistributions in binary form must reproduce the above copyright
13.\"    notice, this list of conditions and the following disclaimer in the
14.\"    documentation and/or other materials provided with the distribution.
15.\"
16.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26.\" SUCH DAMAGE.
27.\"
28.\" $FreeBSD$
29.\"
30.Dd November 8, 2021
31.Dt VOP_ALLOCATE 9
32.Os
33.Sh NAME
34.Nm VOP_ALLOCATE
35.Nd allocate storage for a file
36.Sh SYNOPSIS
37.In sys/param.h
38.In sys/vnode.h
39.Ft int
40.Fo VOP_ALLOCATE
41.Fa "struct vnode *vp"
42.Fa "off_t *offset"
43.Fa "off_t *len"
44.Fa "int ioflag"
45.Fa "struct ucred *cred"
46.Fc
47.Sh DESCRIPTION
48This call allocates storage for a range of offsets in a file.
49It is used to implement the
50.Xr posix_fallocate
51system call.
52.Pp
53Its arguments are:
54.Bl -tag -width offset
55.It Fa vp
56The vnode of the file.
57.It Fa offset
58The start of the range to allocate storage for in the file.
59.It Fa len
60The length of the range to allocate storage for in the file.
61.It Fa ioflag
62Directives and hints to be given to the file system.
63.It Fa cred
64The credentials of the caller.
65.El
66.Pp
67The
68.Fa offset
69and
70.Fa len
71arguments are updated to reflect the portion of the range that
72still needs to be allocated on return.
73A partial allocation is considered a successful operation.
74The file's contents are not changed.
75.Sh LOCKS
76The file should be exclusively locked on entry and will still be locked on exit.
77.Sh RETURN VALUES
78Zero is returned if the call is successful, otherwise an appropriate
79error code is returned.
80.Sh ERRORS
81.Bl -tag -width Er
82.It Bq Er EFBIG
83An attempt was made to write a file that exceeds the process's file size
84limit or the maximum file size.
85.It Bq Er ENOSPC
86The file system is full.
87.It Bq Er EPERM
88An append-only flag is set on the file, but the caller is attempting to
89write before the current end of file.
90.El
91.Sh SEE ALSO
92.Xr vnode 9 ,
93.Xr VOP_READ 9 ,
94.Xr VOP_WRITE 9
95