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

/*
 * Copyright (c) 1999,2001-2002 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This 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 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	*
	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
9bccf70c	23	/* (c) 1997-1998,2001 Apple Computer, Inc. All Rights Reserved */
1c79356b A	24	/*
	25	* Copyright (c) 1991, 1993
	26	* The Regents of the University of California. All rights reserved.
	27	*
	28	* This code is derived from software contributed to Berkeley by
	29	* Scooter Morris at Genentech Inc.
	30	*
	31	* Redistribution and use in source and binary forms, with or without
	32	* modification, are permitted provided that the following conditions
	33	* are met:
	34	* 1. Redistributions of source code must retain the above copyright
	35	* notice, this list of conditions and the following disclaimer.
	36	* 2. Redistributions in binary form must reproduce the above copyright
	37	* notice, this list of conditions and the following disclaimer in the
	38	* documentation and/or other materials provided with the distribution.
	39	* 3. All advertising materials mentioning features or use of this software
	40	* must display the following acknowledgement:
	41	* This product includes software developed by the University of
	42	* California, Berkeley and its contributors.
	43	* 4. Neither the name of the University nor the names of its contributors
	44	* may be used to endorse or promote products derived from this software
	45	* without specific prior written permission.
	46	*
	47	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	48	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	49	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	50	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	51	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	52	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	53	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	54	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	55	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	56	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	57	* SUCH DAMAGE.
	58	*
	59	*
	60	* @(#)hfs_lockf.h 1.0 5/5/98
	61	* derived from @(#)lockf.h 8.2 (Berkeley) 10/26/94
	62	*/
	63
9bccf70c A	64	#ifndef __HFS_LOCKF__
	65	#define __HFS_LOCKF__
	66
	67	#include <sys/appleapiopts.h>
	68
	69	#ifdef KERNEL
	70	#ifdef __APPLE_API_PRIVATE
1c79356b A	71	/*
	72	* The hfslockf structure is a kernel structure which contains the information
	73	* associated with a byte range lock. The hfslockf structures are linked into
9bccf70c	74	* a cnode's file fork. Locks are sorted by the starting byte of the lock for
1c79356b A	75	* efficiency.
	76	*/
	77	TAILQ_HEAD(locklist, hfslockf);
	78
	79	struct hfslockf {
	80	short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
	81	short lf_type; /* Lock type: F_RDLCK, F_WRLCK */
	82	off_t lf_start; /* Byte # of the start of the lock */
	83	off_t lf_end; /* Byte # of the end of the lock (-1=EOF) */
	84	caddr_t lf_id; /* Id of the resource holding the lock */
9bccf70c A	85	struct filefork lf_fork; / Back pointer to the file fork */
9bccf70c A	86	struct hfslockf lf_next; / Pointer to the next lock on this fork */
1c79356b A	87	struct locklist lf_blkhd; /* List of requests blocked on this lock */
	88	TAILQ_ENTRY(hfslockf) lf_block;/* A request waiting for a lock */
	89	};
	90
	91	/* Maximum length of sleep chains to traverse to try and detect deadlock. */
	92	#define MAXDEPTH 50
	93
	94	__BEGIN_DECLS
	95	void hfs_addblock __P((struct hfslockf , struct hfslockf ));
	96	int hfs_clearlock __P((struct hfslockf *));
	97	int hfs_findoverlap __P((struct hfslockf *,
	98	struct hfslockf , int, struct hfslockf , struct hfslockf ));
	99	struct hfslockf *
	100	hfs_getblock __P((struct hfslockf *));
	101	int hfs_getlock __P((struct hfslockf , struct flock ));
	102	int hfs_setlock __P((struct hfslockf *));
	103	void hfs_split __P((struct hfslockf , struct hfslockf ));
	104	void hfs_wakelock __P((struct hfslockf *));
	105	__END_DECLS
	106
	107	#ifdef LOCKF_DEBUG
	108	extern int lockf_debug;
	109
	110	__BEGIN_DECLS
	111	void hfs_lprint __P((char , struct hfslockf ));
	112	void hfs_lprintlist __P((char , struct hfslockf ));
	113	__END_DECLS
9bccf70c A	114	#endif /* LOCKF_DEBUG */
	115	#endif /* __APPLE_API_PRIVATE */
	116	#endif /* KERNEL */
	117	#endif /* __HFS_LOCKF__ */