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.Dd September 9, 2019 28.Dt VM_PAGE_WIRE 9 29.Os 30.Sh NAME 31.Nm vm_page_wire , 32.Nm vm_page_unwire , 33.Nm vm_page_unwire_noq 34.Nd "wire and unwire pages" 35.Sh SYNOPSIS 36.In sys/param.h 37.In vm/vm.h 38.In vm/vm_page.h 39.Ft void 40.Fn vm_page_wire "vm_page_t m" 41.Ft bool 42.Fn vm_page_wire_mapped "vm_page_t m" 43.Ft void 44.Fn vm_page_unwire "vm_page_t m" "int queue" 45.Ft bool 46.Fn vm_page_unwire_noq "vm_page_t m" 47.Sh DESCRIPTION 48The 49.Fn vm_page_wire 50and 51.Fn vm_page_wire_mapped 52functions wire the page, which prevents it from being reclaimed by the page 53daemon or when its containing object is destroyed. 54Both functions require that the page belong to an object. 55The 56.Fn vm_page_wire_mapped 57function is for use by the 58.Xr pmap 9 59layer following a lookup. 60This function may fail if mappings of the page are concurrently 61being destroyed, in which case it will return false. 62.Pp 63The 64.Fn vm_page_unwire 65and 66.Fn vm_page_unwire_noq 67functions release a wiring of a page. 68The 69.Fn vm_page_unwire 70function takes a queue index and will insert the page into the 71corresponding page queue upon releasing its last wiring. 72If the page does not belong to an object and no other references 73to the page exist, 74.Fn vm_page_unwire 75will free the page. 76.Fn vm_page_unwire_noq 77releases the wiring and returns true if it was the last wiring 78of the page. 79.Sh AUTHORS 80This manual page was written by 81.An Chad David Aq Mt davidc@acns.ab.ca . 82