.\"	$OpenBSD: uvm_vslock.9,v 1.2 2019/12/06 11:09:47 mpi Exp $
.\"	$NetBSD: uvm.9,v 1.14 2000/06/29 06:08:44 mrg Exp $
.\"
.\" Copyright (c) 1998 Matthew R. Green
.\" All rights reserved.
.\"
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.Dd $Mdocdate: December 6 2019 $
.Dt UVM_VSLOCK 9
.Os
.Sh NAME
.Nm uvm_vslock ,
.Nm uvm_vsunlock ,
.Nm uvm_vslock_device ,
.Nm uvm_vsunlock_device
.Nd wire user memory for I/O
.Sh SYNOPSIS
.In uvm/uvm_extern.h
.Ft void
.Fn uvm_vslock "struct proc *p" "caddr_t addr" "size_t len" \
               "vm_prot_t access_type"
.Ft void
.Fn uvm_vsunlock "struct proc *p" "caddr_t addr" "size_t len"
.Ft int
.Fn uvm_vslock_device "struct proc *p" "void *addr" "size_t len" \
               "vm_prot_t access_type" "void **retp"
.Ft void
.Fn uvm_vsunlock_device "struct proc *p" "void *addr" "size_t len" "void *map"
.Sh DESCRIPTION
The
.Fn uvm_vslock
family of functions
control the wiring and unwiring of pages for process
.Fa p
from
.Fa addr
to
.Fa addr + len .
The
.Fa access_type
argument is passed to
.Xr uvm_fault 9 .
.Pp
.Fn uvm_vslock_device
also checks if the pages are DMA reachable.
When they aren't, it bounces their content into a newly created mapping
returned in
.Fa retp .
.Fn uvm_vsunlock_device
will release this memory mapping pointed by
.Fa map .
.Sh SEE ALSO
.Xr uvm_fault 9