1/*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28/*
29 * Copyright (c) 1998 Apple Computer, Inc.  All rights reserved.
30 *
31 * HISTORY
32 *
33 */
34
35/*
36 * Multiprocessor locks used within the shared memory area between the
37 * kernel and event system.  These must work in both user and kernel mode.
38 *
39 * These routines are public, for the purpose of writing frame buffer device
40 * drivers which handle their own cursors.  Certain architectures define a
41 * generic display class which handles cursor drawing and is subclassed by
42 * driver writers.  These drivers need not be concerned with the following
43 * types and definitions.
44 *
45 * The ev_lock(), ev_unlock(), and ev_try_lock() functions are available only
46 * to drivers built in or dynamically loaded into the kernel, and to DPS
47 * drivers built in or dynamically loaded into the Window Server.  They do not
48 * exist in any shared library.
49 *
50 * --> They're now in IOKit user lib.
51 */
52
53#ifndef _IOKIT_IOSHAREDLOCK_H
54#define _IOKIT_IOSHAREDLOCK_H
55
56#ifdef __cplusplus
57extern "C" {
58#endif
59
60// should be 32 bytes on PPC
61typedef volatile int		IOSharedLockData;
62typedef IOSharedLockData    *   IOSharedLock;
63
64#define IOSpinLockInit(l)	(*(l) = (IOSharedLockData)0)
65
66#ifndef KERNEL
67extern void IOSpinLock(IOSharedLock l);
68#endif
69
70extern void IOSpinUnlock(IOSharedLock l);
71extern boolean_t IOTrySpinLock(IOSharedLock l);
72
73/* exact same stuff & implementation */
74
75typedef IOSharedLockData 	ev_lock_data_t;
76typedef ev_lock_data_t	    *	ev_lock_t;
77
78#define ev_init_lock(l)		(*(l) = (ev_lock_data_t)0)
79// needs isync?
80//#define ev_is_locked(l)	(*(l) != (ev_lock_data_t)0)
81
82#ifndef KERNEL
83extern void ev_lock(ev_lock_t l);		// Spin lock!
84#endif
85
86extern void ev_unlock(ev_lock_t l);
87extern boolean_t ev_try_lock(ev_lock_t l);
88
89#ifdef __cplusplus
90}
91#endif
92#endif /* ! _IOKIT_IOSHAREDLOCK_H */
93