[apple/xnu.git] / bsd / hfs / hfs_lockf.h

/*
 * Copyright (c) 1999,2001-2002 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

/*	(c) 1997-1998,2001 Apple Computer, Inc.  All Rights Reserved */
/*
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Scooter Morris at Genentech Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *
 *	@(#)hfs_lockf.h	1.0 5/5/98
 *	derived from @(#)lockf.h	8.2 (Berkeley) 10/26/94
 */

#ifndef  __HFS_LOCKF__
#define  __HFS_LOCKF__

#include <sys/appleapiopts.h>

#ifdef KERNEL
#ifdef __APPLE_API_PRIVATE
/*
 * The hfslockf structure is a kernel structure which contains the information
 * associated with a byte range lock.  The hfslockf structures are linked into
 * a cnode's file fork.  Locks are sorted by the starting byte of the lock for
 * efficiency.
 */
TAILQ_HEAD(locklist, hfslockf);

struct hfslockf {
	short	lf_flags;	    /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
	short	lf_type;	    /* Lock type: F_RDLCK, F_WRLCK */
	off_t	lf_start;	    /* Byte # of the start of the lock */
	off_t	lf_end;		    /* Byte # of the end of the lock (-1=EOF) */
	caddr_t	lf_id;		    /* Id of the resource holding the lock */
	struct	filefork *lf_fork;  /* Back pointer to the file fork */
	struct	hfslockf *lf_next;  /* Pointer to the next lock on this fork */
	struct	locklist lf_blkhd;  /* List of requests blocked on this lock */
	TAILQ_ENTRY(hfslockf) lf_block;/* A request waiting for a lock */
};

/* Maximum length of sleep chains to traverse to try and detect deadlock. */
#define MAXDEPTH 50

__BEGIN_DECLS
void	 hfs_addblock __P((struct hfslockf *, struct hfslockf *));
int	 hfs_clearlock __P((struct hfslockf *));
int	 hfs_findoverlap __P((struct hfslockf *,
	    struct hfslockf *, int, struct hfslockf ***, struct hfslockf **));
struct hfslockf *
	 hfs_getblock __P((struct hfslockf *));
int	 hfs_getlock __P((struct hfslockf *, struct flock *));
int	 hfs_setlock __P((struct hfslockf *));
void	 hfs_split __P((struct hfslockf *, struct hfslockf *));
void	 hfs_wakelock __P((struct hfslockf *));
__END_DECLS

#ifdef LOCKF_DEBUG
extern int lockf_debug;

__BEGIN_DECLS
void	hfs_lprint __P((char *, struct hfslockf *));
void	hfs_lprintlist __P((char *, struct hfslockf *));
__END_DECLS
#endif	/* LOCKF_DEBUG */
#endif /* __APPLE_API_PRIVATE */
#endif /* KERNEL */
#endif  /* __HFS_LOCKF__ */
Commit	Line	Data
1c79356b	1	/*
9bccf70c	2	* Copyright (c) 1999,2001-2002 Apple Computer, Inc. All rights reserved.
1c79356b A	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
43866e37	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
43866e37 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
43866e37 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25
9bccf70c	26	/* (c) 1997-1998,2001 Apple Computer, Inc. All Rights Reserved */
1c79356b A	27	/*
	28	* Copyright (c) 1991, 1993
	29	* The Regents of the University of California. All rights reserved.
	30	*
	31	* This code is derived from software contributed to Berkeley by
	32	* Scooter Morris at Genentech Inc.
	33	*
	34	* Redistribution and use in source and binary forms, with or without
	35	* modification, are permitted provided that the following conditions
	36	* are met:
	37	* 1. Redistributions of source code must retain the above copyright
	38	* notice, this list of conditions and the following disclaimer.
	39	* 2. Redistributions in binary form must reproduce the above copyright
	40	* notice, this list of conditions and the following disclaimer in the
	41	* documentation and/or other materials provided with the distribution.
	42	* 3. All advertising materials mentioning features or use of this software
	43	* must display the following acknowledgement:
	44	* This product includes software developed by the University of
	45	* California, Berkeley and its contributors.
	46	* 4. Neither the name of the University nor the names of its contributors
	47	* may be used to endorse or promote products derived from this software
	48	* without specific prior written permission.
	49	*
	50	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	51	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	52	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	53	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	54	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	55	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	56	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	57	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	58	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	59	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	60	* SUCH DAMAGE.
	61	*
	62	*
	63	* @(#)hfs_lockf.h 1.0 5/5/98
	64	* derived from @(#)lockf.h 8.2 (Berkeley) 10/26/94
	65	*/
	66
9bccf70c A	67	#ifndef __HFS_LOCKF__
	68	#define __HFS_LOCKF__
	69
	70	#include <sys/appleapiopts.h>
	71
	72	#ifdef KERNEL
	73	#ifdef __APPLE_API_PRIVATE
1c79356b A	74	/*
	75	* The hfslockf structure is a kernel structure which contains the information
	76	* associated with a byte range lock. The hfslockf structures are linked into
9bccf70c	77	* a cnode's file fork. Locks are sorted by the starting byte of the lock for
1c79356b A	78	* efficiency.
	79	*/
	80	TAILQ_HEAD(locklist, hfslockf);
	81
	82	struct hfslockf {
	83	short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
	84	short lf_type; /* Lock type: F_RDLCK, F_WRLCK */
	85	off_t lf_start; /* Byte # of the start of the lock */
	86	off_t lf_end; /* Byte # of the end of the lock (-1=EOF) */
	87	caddr_t lf_id; /* Id of the resource holding the lock */
9bccf70c A	88	struct filefork lf_fork; / Back pointer to the file fork */
9bccf70c A	89	struct hfslockf lf_next; / Pointer to the next lock on this fork */
1c79356b A	90	struct locklist lf_blkhd; /* List of requests blocked on this lock */
	91	TAILQ_ENTRY(hfslockf) lf_block;/* A request waiting for a lock */
	92	};
	93
	94	/* Maximum length of sleep chains to traverse to try and detect deadlock. */
	95	#define MAXDEPTH 50
	96
	97	__BEGIN_DECLS
	98	void hfs_addblock __P((struct hfslockf , struct hfslockf ));
	99	int hfs_clearlock __P((struct hfslockf *));
	100	int hfs_findoverlap __P((struct hfslockf *,
	101	struct hfslockf , int, struct hfslockf , struct hfslockf ));
	102	struct hfslockf *
	103	hfs_getblock __P((struct hfslockf *));
	104	int hfs_getlock __P((struct hfslockf , struct flock ));
	105	int hfs_setlock __P((struct hfslockf *));
	106	void hfs_split __P((struct hfslockf , struct hfslockf ));
	107	void hfs_wakelock __P((struct hfslockf *));
	108	__END_DECLS
	109
	110	#ifdef LOCKF_DEBUG
	111	extern int lockf_debug;
	112
	113	__BEGIN_DECLS
	114	void hfs_lprint __P((char , struct hfslockf ));
	115	void hfs_lprintlist __P((char , struct hfslockf ));
	116	__END_DECLS
9bccf70c A	117	#endif /* LOCKF_DEBUG */
	118	#endif /* __APPLE_API_PRIVATE */
	119	#endif /* KERNEL */
	120	#endif /* __HFS_LOCKF__ */