2001-07-18 06:09:13 +00:00
|
|
|
.\"
|
|
|
|
|
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
|
|
|
|
|
.\"
|
|
|
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
|
|
|
.\" modification, are permitted provided that the following conditions
|
|
|
|
|
.\" are met:
|
|
|
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
|
|
|
.\" notice(s), this list of conditions and the following disclaimer as
|
|
|
|
|
.\" the first lines of this file unmodified other than the possible
|
|
|
|
|
.\" addition of one or more copyright notices.
|
|
|
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
|
|
|
.\" notice(s), this list of conditions and the following disclaimer in the
|
|
|
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
|
|
|
.\"
|
|
|
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
|
|
|
|
|
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
|
|
|
|
|
.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
|
|
|
|
.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY
|
|
|
|
|
.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
|
|
|
.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
|
|
|
.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
|
|
|
|
|
.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
|
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
|
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
|
|
|
|
|
.\" DAMAGE.
|
|
|
|
|
.\"
|
|
|
|
|
.\" $FreeBSD$
|
|
|
|
|
.\"
|
|
|
|
|
.Dd July 17, 2001
|
|
|
|
|
.Dt VM_PAGE_IO_START 9
|
|
|
|
|
.Os
|
|
|
|
|
.Sh NAME
|
|
|
|
|
.Nm vm_page_io_start ,
|
2001-10-04 10:10:56 +00:00
|
|
|
.Nm vm_page_io_finish
|
2001-07-18 06:09:13 +00:00
|
|
|
.Nd "ready or unready a page for I/O"
|
|
|
|
|
.Sh SYNOPSIS
|
|
|
|
|
.In sys/param.h
|
|
|
|
|
.In vm/vm.h
|
|
|
|
|
.In vm/vm_page.h
|
|
|
|
|
.Ft void
|
|
|
|
|
.Fn vm_page_io_start "vm_page_t m"
|
|
|
|
|
.Ft void
|
2001-10-04 10:10:56 +00:00
|
|
|
.Fn vm_page_io_finish "vm_page_t m"
|
2001-07-18 06:09:13 +00:00
|
|
|
.Sh DESCRIPTION
|
|
|
|
|
The
|
|
|
|
|
.Fn vm_page_io_start
|
2004-05-05 10:01:06 +00:00
|
|
|
function prepares the page for I/O by incrementing its busy flag by one.
|
2001-07-18 06:09:13 +00:00
|
|
|
.Pp
|
|
|
|
|
The
|
2001-10-04 10:10:56 +00:00
|
|
|
.Fn vm_page_io_finish
|
2001-07-18 06:09:13 +00:00
|
|
|
function lowers the busy count on the page by one, if the resulting busy
|
2004-05-05 10:01:06 +00:00
|
|
|
count is zero, a
|
|
|
|
|
.Xr wakeup 9
|
|
|
|
|
will be issued if the page has been marked
|
2001-08-08 08:24:48 +00:00
|
|
|
.Dv PG_WANTED .
|
|
|
|
|
A page is typically marked
|
|
|
|
|
.Dv PG_WANTED
|
2004-05-05 10:01:06 +00:00
|
|
|
by a thread to register its interest in
|
|
|
|
|
the page to either complete I/O or becoming available for general use.
|
2001-07-18 06:09:13 +00:00
|
|
|
.Sh AUTHORS
|
2001-08-08 08:24:48 +00:00
|
|
|
.An -nosplit
|
2001-07-18 06:09:13 +00:00
|
|
|
This man page was written by
|
2001-08-08 08:24:48 +00:00
|
|
|
.An Chad David Aq davidc@acns.ab.ca
|
2001-07-18 06:09:13 +00:00
|
|
|
and
|
2001-08-08 08:24:48 +00:00
|
|
|
.An Alfred Perlstein Aq alfred@FreeBSD.org .
|
