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1.\" 2.\" Copyright (c) 2003 Bruce M Simpson <firstname.lastname@example.org> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD$ 27.\" 28.Dd July 19, 2003 29.Dt VM_MAP_WIRE 9 30.Os 31.Sh NAME 32.Nm vm_map_wire , 33.Nm vm_map_unwire 34.Nd manage page wiring within a virtual memory map 35.Sh SYNOPSIS 36.In sys/param.h 37.In vm/vm.h 38.In vm/vm_map.h 39.Ft int 40.Fn vm_map_wire "vm_map_t map" "vm_offset_t start" "vm_offset_t end" "int flags" 41.Ft int 42.Fo vm_map_unwire 43.Fa "vm_map_t map" "vm_offset_t start" "vm_offset_t end" "int flags" 44.Fc 45.Sh DESCRIPTION 46The 47.Fn vm_map_wire 48function is responsible for wiring pages in the range between 49.Fa start 50and 51.Fa end 52within the map 53.Fa map . 54Wired pages are locked into physical memory, and may not be paged out 55as long as their wire count remains above zero. 56.Pp 57The 58.Fn vm_map_unwire 59function performs the corresponding unwire operation. 60.Pp 61The 62.Fa flags 63argument is a bit mask, consisting of the following flags: 64.Pp 65If the 66.Dv VM_MAP_WIRE_USER 67flag is set, the function operates within user address space. 68.Pp 69If the 70.Dv VM_MAP_WIRE_HOLESOK 71flag is set, it may operate upon an arbitrary range within the 72address space of 73.Fa map . 74.Pp 75If a contiguous range is desired, callers should explicitly express 76their intent by specifying the 77.Dv VM_MAP_WIRE_NOHOLES 78flag. 79.Sh IMPLEMENTATION NOTES 80Both functions will attempt to acquire a lock on the map using 81.Xr vm_map_lock 9 82and hold it for the duration of the call. 83If they detect 84.Dv MAP_ENTRY_IN_TRANSITION , 85they will call 86.Xr vm_map_unlock_and_wait 9 87until the map becomes available again. 88.Pp 89The map could have changed during this window as it was held by another 90consumer, therefore consumers of this interface should check for this 91condition using the return values below. 92.Sh RETURN VALUES 93The 94.Fn vm_map_wire 95and 96.Fn vm_map_unwire 97functions have identical return values. 98The functions return 99.Dv KERN_SUCCESS 100if all pages within the range were [un]wired successfully. 101.Pp 102Otherwise, if the specified range was not valid, 103or if the map changed while the 104.Dv MAP_ENTRY_IN_TRANSITION 105flag was set, 106.Dv KERN_INVALID_ADDRESS 107is returned. 108.Sh SEE ALSO 109.Xr mlockall 2 , 110.Xr munlockall 2 , 111.Xr vm_map 9 112.Sh AUTHORS 113This manual page was written by 114.An Bruce M Simpson Aq email@example.com .