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.\" 3. All advertising materials mentioning features or use of this software 18.\" must display the following acknowledgement: 19.\" This product includes software developed by the NetBSD 20.\" Foundation, Inc. and its contributors. 21.\" 4. Neither the name of The NetBSD Foundation nor the names of its 22.\" contributors may be used to endorse or promote products derived 23.\" from this software without specific prior written permission. 24.\" 25.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 26.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE 29.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35.\" POSSIBILITY OF SUCH DAMAGE. 36.\" 37.\" $FreeBSD$ 38.\" 39.Dd August 10, 2004 40.Dt VSLOCK 9 41.Os 42.Sh NAME 43.Nm vslock , 44.Nm vsunlock 45.Nd lock/unlock user space addresses in memory 46.Sh SYNOPSIS 47.In sys/param.h 48.In sys/proc.h 49.In vm/vm.h 50.In vm/vm_extern.h 51.Ft int 52.Fn vslock "void *addr" "size_t len" 53.Ft void 54.Fn vsunlock "void *addr" "size_t len" 55.Sh DESCRIPTION 56The 57.Fn vslock 58and 59.Fn vsunlock 60functions respectively lock and unlock a range of 61addresses belonging to the currently running process into memory. 62The actual amount of memory locked is a multiple of the machine's page size. 63The starting page number is computed by truncating 64.Fa addr 65to the nearest preceding page boundary, and by rounding up 66.Fa addr + 67.Fa len 68to the next page boundary. 69The process context to use for this operation is taken from the 70global variable 71.Va curproc . 72.Sh RETURN VALUES 73The 74.Fn vslock 75function will return 0 on success, otherwise it will return 76one of the errors listed below. 77.Sh ERRORS 78The 79.Fn vslock 80function will fail if: 81.Bl -tag -width Er 82.It Bq Er EINVAL 83The 84.Fa addr 85and 86.Fa len 87parameters specify a memory range that wraps around the end of the 88machine address space. 89.It Bq Er ENOMEM 90The size of the specified address range exceeds the system 91limit on locked memory. 92.It Bq Er ENOMEM 93Locking the requested address range would cause the process to exceed 94its per-process locked memory limit. 95.It Bq Er EFAULT 96Some portion of the indicated address range is not allocated. 97There was an error faulting/mapping a page. 98.El 99