Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.

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$FreeBSD$

.Dd July 17, 2001 .Dt VM_PAGE_IO_START 9 .Os .Sh NAME .Nm vm_page_io_start , .Nm vm_page_io_finish .Nd "ready or unready a page for I/O" .Sh SYNOPSIS n sys/param.h n vm/vm.h n vm/vm_page.h .Ft void .Fn vm_page_io_start "vm_page_t m" .Ft void .Fn vm_page_io_finish "vm_page_t m" .Sh DESCRIPTION The .Fn vm_page_io_start function prepares the page for I/O by incrementing its busy flag by one.

p The .Fn vm_page_io_finish function lowers the busy count on the page by one, if the resulting busy count is zero, a .Xr wakeup 9 will be issued if the page has been marked .Dv VPO_WANTED . A page is typically marked .Dv VPO_WANTED by a thread to register its interest in the page to either complete I/O or becoming available for general use. .Sh AUTHORS .An -nosplit This manual page was written by .An Chad David Aq davidc@acns.ab.ca and .An Alfred Perlstein Aq alfred@FreeBSD.org .