Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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$FreeBSD$
.Dd September 9, 2019 .Dt VM_PAGE_WIRE 9 .Os .Sh NAME .Nm vm_page_wire , .Nm vm_page_unwire , .Nm vm_page_unwire_noq .Nd "wire and unwire pages" .Sh SYNOPSIS n sys/param.h n vm/vm.h n vm/vm_page.h .Ft void .Fn vm_page_wire "vm_page_t m" .Ft bool .Fn vm_page_wire_mapped "vm_page_t m" .Ft void .Fn vm_page_unwire "vm_page_t m" "int queue" .Ft bool .Fn vm_page_unwire_noq "vm_page_t m" .Sh DESCRIPTION The .Fn vm_page_wire and .Fn vm_page_wire_mapped functions wire the page, which prevents it from being reclaimed by the page daemon or when its containing object is destroyed. Both functions require that the page belong to an object. The .Fn vm_page_wire_mapped function is for use by the .Xr pmap 9 layer following a lookup. This function may fail if mappings of the page are concurrently being destroyed, in which case it will return false.
p The .Fn vm_page_unwire and .Fn vm_page_unwire_noq functions release a wiring of a page. The .Fn vm_page_unwire function takes a queue index and will insert the page into the corresponding page queue upon releasing its last wiring. If the page does not belong to an object and no other references to the page exist, .Fn vm_page_unwire will free the page. .Fn vm_page_unwire_noq releases the wiring and returns true if it was the last wiring of the page. .Sh AUTHORS This manual page was written by .An Chad David Aq Mt davidc@acns.ab.ca .