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1c79356b 1/*
91447636 2 * Copyright (c) 2004-2005 Apple Computer, Inc. All rights reserved.
1c79356b 3 *
8ad349bb 4 * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
1c79356b 5 *
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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
10 * License may not be used to create, or enable the creation or
11 * redistribution of, unlawful or unlicensed copies of an Apple operating
12 * system, or to circumvent, violate, or enable the circumvention or
13 * violation of, any terms of an Apple operating system software license
14 * agreement.
15 *
16 * Please obtain a copy of the License at
17 * http://www.opensource.apple.com/apsl/ and read it before using this
18 * file.
19 *
20 * The Original Code and all software distributed under the License are
21 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
22 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
23 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
25 * Please see the License for the specific language governing rights and
26 * limitations under the License.
27 *
28 * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
1c79356b 29 */
1c79356b
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30/*
31 * Copyright (c) 1991, 1993
32 * The Regents of the University of California. All rights reserved.
33 *
34 * This code is derived from software contributed to Berkeley by
35 * Scooter Morris at Genentech Inc.
36 *
37 * Redistribution and use in source and binary forms, with or without
38 * modification, are permitted provided that the following conditions
39 * are met:
40 * 1. Redistributions of source code must retain the above copyright
41 * notice, this list of conditions and the following disclaimer.
42 * 2. Redistributions in binary form must reproduce the above copyright
43 * notice, this list of conditions and the following disclaimer in the
44 * documentation and/or other materials provided with the distribution.
1c79356b
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45 * 4. Neither the name of the University nor the names of its contributors
46 * may be used to endorse or promote products derived from this software
47 * without specific prior written permission.
48 *
49 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59 * SUCH DAMAGE.
60 *
61 * @(#)lockf.h 8.1 (Berkeley) 6/11/93
91447636 62 * $FreeBSD: src/sys/sys/lockf.h,v 1.16 2004/04/07 04:19:49 imp Exp $
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63 */
64
65#ifndef _SYS_LOCKF_H_
66#define _SYS_LOCKF_H_
67
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68#include <sys/queue.h>
69#include <sys/cdefs.h>
70
71struct vnop_advlock_args;
72struct vnode;
73
74#ifdef MALLOC_DECLARE
75MALLOC_DECLARE(M_LOCKF);
76#endif
9bccf70c 77
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78/*
79 * The lockf structure is a kernel structure which contains the information
80 * associated with a byte range lock. The lockf structures are linked into
81 * the inode structure. Locks are sorted by the starting byte of the lock for
82 * efficiency.
83 */
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84TAILQ_HEAD(locklist, lockf);
85
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86#if __DARWIN_ALIGN_POWER
87#pragma options align=power
88#endif
91447636 89
1c79356b 90struct lockf {
91447636 91 short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
1c79356b 92 short lf_type; /* Lock type: F_RDLCK, F_WRLCK */
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93 off_t lf_start; /* Byte # of the start of the lock */
94 off_t lf_end; /* Byte # of the end of the lock (-1=EOF) */
95 caddr_t lf_id; /* Id of the resource holding the lock */
96 struct lockf **lf_head; /* Back pointer to the head of the locf list */
97 struct vnode *lf_vnode; /* Back pointer to the inode */
98 struct lockf *lf_next; /* Pointer to the next lock on this inode */
99 struct locklist lf_blkhd; /* List of requests blocked on this lock */
100 TAILQ_ENTRY(lockf) lf_block;/* A request waiting for a lock */
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101};
102
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103#if __DARWIN_ALIGN_POWER
104#pragma options align=reset
105#endif
91447636 106
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107/* Maximum length of sleep chains to traverse to try and detect deadlock. */
108#define MAXDEPTH 50
109
110__BEGIN_DECLS
1c79356b 111
91447636 112int lf_advlock(struct vnop_advlock_args *);
1c79356b 113
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114#ifdef LOCKF_DEBUG
115void lf_print(char *, struct lockf *);
116void lf_printlist(char *, struct lockf *);
117#endif
9bccf70c 118
91447636 119__END_DECLS
9bccf70c 120
1c79356b 121#endif /* !_SYS_LOCKF_H_ */