2 * Copyright (c) 2003 Matthew Dillon <dillon@backplane.com>
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
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.
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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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
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.
30 * $DragonFly: src/sys/vm/vm_rangelock.c,v 1.1 2003/07/22 17:03:35 dillon Exp $
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>
38 #include <sys/mount.h>
39 #include <sys/kernel.h>
40 #include <sys/sysctl.h>
43 #include <vm/vm_param.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>
56 * Note: these routines are currently greatly simplified and unoptimized.
58 * Locks are sorted by base address.
61 shlock_range(vm_object_lock_t lock, vm_object_t object, off_t base, off_t bytes)
63 struct vm_object_lock **plock;
64 vm_object_lock_t scan;
67 * Locate the insertion point and check for conflicts
70 for (plock = &object->range_locks;
71 (scan = *plock) != NULL;
74 if (base < scan->base + scan->bytes && base + bytes > scan->base) {
75 if (scan->type != VMOBJ_LOCK_SHARED) {
83 exlock_range(vm_object_lock_t lock, vm_object_t object, off_t base, off_t bytes)
88 unlock_range(vm_object_lock_t lock)