1.\" $NetBSD: vslock.9,v 1.1 1996/06/15 20:47:29 pk Exp $ 2.\" 3.\" Copyright (c) 1996 The NetBSD Foundation, Inc. 4.\" All rights reserved. 5.\" 6.\" This code is derived from software contributed to The NetBSD Foundation 7.\" by Paul Kranenburg. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 19.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 20.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 21.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 22.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28.\" POSSIBILITY OF SUCH DAMAGE. 29.\" 30.\" $FreeBSD$ 31.\" 32.Dd August 29, 2012 33.Dt VSLOCK 9 34.Os 35.Sh NAME 36.Nm vslock , 37.Nm vsunlock 38.Nd lock/unlock user space addresses in memory 39.Sh SYNOPSIS 40.In sys/param.h 41.In sys/proc.h 42.In vm/vm.h 43.In vm/vm_extern.h 44.Ft int 45.Fn vslock "void *addr" "size_t len" 46.Ft void 47.Fn vsunlock "void *addr" "size_t len" 48.Sh DESCRIPTION 49The 50.Fn vslock 51and 52.Fn vsunlock 53functions respectively lock and unlock a range of 54addresses belonging to the currently running process into memory. 55The actual amount of memory locked is a multiple of the machine's page size. 56The starting page number is computed by truncating 57.Fa addr 58to the nearest preceding page boundary, and by rounding up 59.Fa addr + 60.Fa len 61to the next page boundary. 62The process context to use for this operation is taken from the 63global variable 64.Va curproc . 65.Sh RETURN VALUES 66The 67.Fn vslock 68function will return 0 on success, otherwise it will return 69one of the errors listed below. 70.Sh ERRORS 71The 72.Fn vslock 73function will fail if: 74.Bl -tag -width Er 75.It Bq Er EINVAL 76The 77.Fa addr 78and 79.Fa len 80parameters specify a memory range that wraps around the end of the 81machine address space. 82.It Bq Er ENOMEM 83The size of the specified address range exceeds the system 84limit on locked memory. 85.It Bq Er EFAULT 86Some portion of the indicated address range is not allocated. 87There was an error faulting/mapping a page. 88.El 89