gems-kernel/source/THIRDPARTY/xnu/bsd/sys/lockf.h
2024-06-03 11:29:39 -05:00

121 lines
5 KiB
C

/*
* Copyright (c) 2004-2018 Apple Inc. All rights reserved.
*
* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
* 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. The rights granted to you under the License
* may not be used to create, or enable the creation or redistribution of,
* unlawful or unlicensed copies of an Apple operating system, or to
* circumvent, violate, or enable the circumvention or violation of, any
* terms of an Apple operating system software license agreement.
*
* 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_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* 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.
* 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.
*
* @(#)lockf.h 8.1 (Berkeley) 6/11/93
* $FreeBSD: src/sys/sys/lockf.h,v 1.16 2004/04/07 04:19:49 imp Exp $
*/
#ifndef _SYS_LOCKF_H_
#define _SYS_LOCKF_H_
#include <sys/queue.h>
#include <sys/cdefs.h>
#include <sys/types.h>
struct vnop_advlock_args;
struct vnode;
#if IMPORTANCE_INHERITANCE
#define LF_NOT_BOOSTED 0
#define LF_BOOSTED 1
#endif /* IMPORTANCE_INHERITANCE */
/*
* The lockf structure is a kernel structure which contains the information
* associated with a byte range lock. The lockf structures are linked into
* the vnode structure. Locks are sorted by the starting byte of the lock for
* efficiency after they have been committed; uncommitted locks are on the list
* head so they may quickly be accessed, and are both short lived and transient.
*/
TAILQ_HEAD(locklist, lockf);
struct lockf {
short lf_flags; /* Semantics: F_POSIX, F_FLOCK, F_WAIT */
short lf_type; /* Lock type: F_RDLCK, F_WRLCK */
#if IMPORTANCE_INHERITANCE
int lf_boosted; /* Is the owner of the lock boosted */
#endif
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 lockf **lf_head; /* Back pointer to the head of the lockf list */
struct vnode *lf_vnode; /* Back pointer to the inode */
struct lockf *lf_next; /* Pointer to the next lock on this inode */
struct locklist lf_blkhd; /* List of requests blocked on this lock */
TAILQ_ENTRY(lockf) lf_block;/* A request waiting for a lock */
struct proc *lf_owner; /* The proc that did the SETLK, if known */
};
__BEGIN_DECLS
#ifdef KERNEL_PRIVATE
void lf_init(void);
int lf_advlock(struct vnop_advlock_args *);
int lf_assert(struct vnop_advlock_args *, void **);
void lf_commit(void *, int);
void lf_abort_advlocks(vnode_t);
#ifdef LOCKF_DEBUG
void lf_print(char *, struct lockf *);
void lf_printlist(char *, struct lockf *);
#endif
#endif /* KERNEL_PRIVATE */
__END_DECLS
#endif /* !_SYS_LOCKF_H_ */