freebsd-dev/share/man/man9/vm_page_grab.9

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.\"
.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
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.\" $FreeBSD$
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.Dd August 7, 2001
.Dt VM_PAGE_GRAB 9
.Os
.Sh NAME
.Nm vm_page_grab
.Nd "returns a page from an object"
.Sh SYNOPSIS
.In sys/param.h
.In vm/vm.h
.In vm/vm_page.h
.Ft vm_page_t
.Fn vm_page_grab "vm_object_t object" "vm_pindex_t pindex" "int allocflags"
.Sh DESCRIPTION
The
.Fn vm_page_grab
function returns the page at
.Fa pindex
from the given object.
If the page exists and is busy,
.Fn vm_page_grab
will sleep while waiting for it.
If the page does not exist, it is allocated.
.Pp
If
.Dv VM_ALLOC_RETRY
is not set in
.Fa allocflags
and the function sleeps, either getting the page from the object
or while allocating it,
.Dv NULL
is returned.
.Sh RETURN VALUES
If successful,
.Fn vm_page_grab
returns the page; otherwise,
.Dv NULL
is returned.
.Sh SEE ALSO
.Xr vm_page_alloc 9
.Sh AUTHORS
This man page was written by
.An Chad David Aq davidc@acns.ab.ca .