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+.\"
+.\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
+.\" 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, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, 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 AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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 21, 2003
+.Dt VM_FAULT_PREFAULT 9
+.Os
+.Sh NAME
+.Nm vm_fault_prefault
+.Nd cluster page faults into a process's address space
+.Sh SYNOPSIS
+.In sys/param.h
+.In vm/vm.h
+.In vm/pmap.h
+.Ft void
+.Fn vm_fault_prefault "pmap_t pmap" "vm_offset_t addra" "vm_map_entry_t entry"
+.Sh DESCRIPTION
+The
+.Fn vm_fault_prefault
+function provides a means of clustering pagefaults into a process's
+address space.
+It operates upon the physical map
+.Fa pmap .
+The
+.Fa entry
+argument specifies the entry to be prefaulted; the
+.Fa addra
+argument specifies the beginning of the mapping in the process's virtual
+address space.
+.Pp
+It is typically called by
+.Fn vm_fault
+after the first page fault.
+It benefits the
+.Xr execve 2
+system call by eliminating repetitive calls to
+.Fn vm_fault ,
+which would otherwise be made to bring the process's executable pages
+into physical memory.
+.Sh IMPLEMENTATION NOTES
+This is a machine-independent function which calls the machine-dependent
+.Xr pmap_is_prefaultable 9
+helper function to determine if a page may be prefaulted into physical memory.
+.Sh SEE ALSO
+.Xr execve 2 ,
+.Xr pmap_is_prefaultable 9
+.Sh AUTHORS
+This manual page was written by
+.An Bruce M Simpson Aq bms@spc.org .