1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as 9.\" the first lines of this file unmodified other than the possible 10.\" addition of one or more copyright notices. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice(s), this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY 16.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 17.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 18.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" 27.\" $FreeBSD$ 28.\" 29.Dd September 9, 2019 30.Dt VM_PAGE_WIRE 9 31.Os 32.Sh NAME 33.Nm vm_page_wire , 34.Nm vm_page_unwire , 35.Nm vm_page_unwire_noq 36.Nd "wire and unwire pages" 37.Sh SYNOPSIS 38.In sys/param.h 39.In vm/vm.h 40.In vm/vm_page.h 41.Ft void 42.Fn vm_page_wire "vm_page_t m" 43.Ft bool 44.Fn vm_page_wire_mapped "vm_page_t m" 45.Ft void 46.Fn vm_page_unwire "vm_page_t m" "int queue" 47.Ft bool 48.Fn vm_page_unwire_noq "vm_page_t m" 49.Sh DESCRIPTION 50The 51.Fn vm_page_wire 52and 53.Fn vm_page_wire_mapped 54functions wire the page, which prevents it from being reclaimed by the page 55daemon or when its containing object is destroyed. 56Both functions require that the page belong to an object. 57The 58.Fn vm_page_wire_mapped 59function is for use by the 60.Xr pmap 9 61layer following a lookup. 62This function may fail if mappings of the page are concurrently 63being destroyed, in which case it will return false. 64.Pp 65The 66.Fn vm_page_unwire 67and 68.Fn vm_page_unwire_noq 69functions release a wiring of a page. 70The 71.Fn vm_page_unwire 72function takes a queue index and will insert the page into the 73corresponding page queue upon releasing its last wiring. 74If the page does not belong to an object and no other references 75to the page exist, 76.Fn vm_page_unwire 77will free the page. 78.Fn vm_page_unwire_noq 79releases the wiring and returns true if it was the last wiring 80of the page. 81.Sh AUTHORS 82This manual page was written by 83.An Chad David Aq Mt davidc@acns.ab.ca . 84