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1/*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * The contents of this file constitute Original Code as defined in and
7 * are subject to the Apple Public Source License Version 1.1 (the
8 * "License"). You may not use this file except in compliance with the
9 * License. Please obtain a copy of the License at
10 * http://www.apple.com/publicsource and read it before using this file.
11 *
12 * This Original Code and all software distributed under the License are
13 * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
14 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
15 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
17 * License for the specific language governing rights and limitations
18 * under the License.
19 *
20 * @APPLE_LICENSE_HEADER_END@
21 */
22/*
23 * Copyright (c) 1998 Apple Computer, Inc. All rights reserved.
24 *
25 * HISTORY
26 *
27 */
28
29/*
30 * Multiprocessor locks used within the shared memory area between the
31 * kernel and event system. These must work in both user and kernel mode.
32 *
33 * These routines are public, for the purpose of writing frame buffer device
34 * drivers which handle their own cursors. Certain architectures define a
35 * generic display class which handles cursor drawing and is subclassed by
36 * driver writers. These drivers need not be concerned with the following
37 * types and definitions.
38 *
39 * The ev_lock(), ev_unlock(), and ev_try_lock() functions are available only
40 * to drivers built in or dynamically loaded into the kernel, and to DPS
41 * drivers built in or dynamically loaded into the Window Server. They do not
42 * exist in any shared library.
43 *
44 * --> They're now in IOKit user lib.
45 */
46
47#ifndef _IOKIT_IOSHAREDLOCK_H
48#define _IOKIT_IOSHAREDLOCK_H
49
50#ifdef __cplusplus
51extern "C" {
52#endif
53
54// should be 32 bytes on PPC
55typedef volatile int IOSharedLockData;
56typedef IOSharedLockData * IOSharedLock;
57
58#define IOSpinLockInit(l) (*(l) = (IOSpinLockData)0)
59
60extern void IOSpinLock(IOSharedLock l);
61extern void IOSpinUnlock(IOSharedLock l);
62extern boolean_t IOTrySpinLock(IOSharedLock l);
63
64/* exact same stuff & implementation */
65
66typedef IOSharedLockData ev_lock_data_t;
67typedef ev_lock_data_t * ev_lock_t;
68
69#define ev_init_lock(l) (*(l) = (ev_lock_data_t)0)
70// needs isync?
71//#define ev_is_locked(l) (*(l) != (ev_lock_data_t)0)
72
73extern void ev_lock(ev_lock_t l); // Spin lock!
74extern void ev_unlock(ev_lock_t l);
75extern boolean_t ev_try_lock(ev_lock_t l);
76
77#ifdef __cplusplus
78}
79#endif
80#endif /* ! _IOKIT_IOSHAREDLOCK_H */