osfmk/kern/lock.h

   1 /*
   2  * Copyright (c) 2000-2005 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,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  *      File:   kern/lock.h
  58  *      Author: Avadis Tevanian, Jr., Michael Wayne Young
  59  *      Date:   1985
  60  *
  61  *      Higher Level Locking primitives definitions
  62  */
  63
  64 #ifdef  KERNEL_PRIVATE
  65
  66 #ifndef _KERN_LOCK_H_
  67 #define _KERN_LOCK_H_
  68
  69 #include <kern/simple_lock.h>
  70 #include <machine/lock.h>
  71 #include <sys/cdefs.h>
  72
  73 __BEGIN_DECLS
  74
  75 #ifndef MACH_KERNEL_PRIVATE
  76
  77 typedef struct __lock__ lock_t;
  78
  79 #else   /* MACH_KERNEL_PRIVATE */
  80
  81 extern void                     lock_init(
  82                                                 lock_t          *lock,
  83                                                 boolean_t       can_sleep,
  84                                                 unsigned short  tag0,
  85                                                 unsigned short  tag1);
  86
  87 #endif  /* MACH_KERNEL_PRIVATE */
  88
  89 extern lock_t            *lock_alloc(
  90                                                 boolean_t       can_sleep,
  91                                                 unsigned short  tag0,
  92                                                 unsigned short  tag1);
  93
  94 extern void                      lock_free(
  95                                                 lock_t          *lock);
  96
  97 extern void                     lock_write(
  98                                                 lock_t          *lock);
  99
 100 extern void                     lock_read(
 101                                                 lock_t          *lock);
 102
 103 extern void                     lock_done(
 104                                                 lock_t          *lock);
 105
 106 extern void                     lock_write_to_read(
 107                                                 lock_t          *lock);
 108
 109 #define lock_read_done(l)               lock_done(l)
 110 #define lock_write_done(l)              lock_done(l)
 111
 112 extern boolean_t         lock_read_to_write(
 113                                                 lock_t          *lock);
 114
 115
 116 /* Sleep, unlocking and then relocking a usimple_lock in the process */
 117 extern wait_result_t    thread_sleep_usimple_lock(
 118                                                         event_t                         event,
 119                                                         usimple_lock_t          lock,
 120                                                         wait_interrupt_t        interruptible);
 121
 122 /* Sleep, unlocking and then relocking a write lock in the process */
 123 extern wait_result_t    thread_sleep_lock_write(
 124                                                         event_t                         event,
 125                                                         lock_t                          *lock,
 126                                                         wait_interrupt_t        interruptible);
 127 __END_DECLS
 128
 129 #ifdef  MACH_KERNEL_PRIVATE
 130
 131 extern wait_result_t    thread_sleep_fast_usimple_lock(
 132                                                         event_t                                 event,
 133                                                         simple_lock_t                   lock,
 134                                                         wait_interrupt_t                 interruptible);
 135 #endif  /* MACH_KERNEL_PRIVATE */
 136
 137 #endif  /* _KERN_LOCK_H_ */
 138
 139 #endif  /* KERNEL_PRIVATE */