Enhance the pmap_kenter*() API and friends, separating out entries which
[dragonfly.git] / sys / vm / vm_rangelock.c
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335dda38
MD
1/*
2 * Copyright (c) 2003 Matthew Dillon <dillon@backplane.com>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * VM range locking module. Range locks within VM objects are used to protect
27 * I/O operations and will eventually also be used in an extended form
28 * for cache coherency control.
29 *
30 * $DragonFly: src/sys/vm/vm_rangelock.c,v 1.1 2003/07/22 17:03:35 dillon Exp $
31 */
32#include <sys/param.h>
33#include <sys/systm.h>
34#include <sys/proc.h> /* for curproc, pageproc */
35#include <sys/vnode.h>
36#include <sys/vmmeter.h>
37#include <sys/mman.h>
38#include <sys/mount.h>
39#include <sys/kernel.h>
40#include <sys/sysctl.h>
41
42#include <vm/vm.h>
43#include <vm/vm_param.h>
44#include <vm/pmap.h>
45#include <vm/vm_map.h>
46#include <vm/vm_object.h>
47#include <vm/vm_page.h>
48#include <vm/vm_pageout.h>
49#include <vm/vm_pager.h>
50#include <vm/swap_pager.h>
51#include <vm/vm_kern.h>
52#include <vm/vm_extern.h>
53#include <vm/vm_zone.h>
54
55/*
56 * Note: these routines are currently greatly simplified and unoptimized.
57 *
58 * Locks are sorted by base address.
59 */
60void
61shlock_range(vm_object_lock_t lock, vm_object_t object, off_t base, off_t bytes)
62{
63 struct vm_object_lock **plock;
64 vm_object_lock_t scan;
65
66 /*
67 * Locate the insertion point and check for conflicts
68 */
69again:
70 for (plock = &object->range_locks;
71 (scan = *plock) != NULL;
72 plock = &scan->next
73 ) {
74 if (base < scan->base + scan->bytes && base + bytes > scan->base) {
75 if (scan->type != VMOBJ_LOCK_SHARED) {
76 tsleep(scan
77 }
78 }
79 }
80}
81
82void
83exlock_range(vm_object_lock_t lock, vm_object_t object, off_t base, off_t bytes)
84{
85}
86
87void
88unlock_range(vm_object_lock_t lock)
89{
90}
91