The Design and Implementation of the FreeBSD Operating System, Second Edition
Now available: The Design and Implementation of the FreeBSD Operating System (Second Edition)


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]

FreeBSD/Linux Kernel Cross Reference
sys/sys/rangelock.h

Version: -  FREEBSD  -  FREEBSD-13-STABLE  -  FREEBSD-13-0  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  l41  -  OPENBSD  -  linux-2.6  -  MK84  -  PLAN9  -  xnu-8792 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
    3  *
    4  * Copyright (c) 2009 Konstantin Belousov <kib@FreeBSD.org>
    5  * All rights reserved.
    6  *
    7  * Redistribution and use in source and binary forms, with or without
    8  * modification, are permitted provided that the following conditions
    9  * are met:
   10  * 1. Redistributions of source code must retain the above copyright
   11  *    notice unmodified, this list of conditions, and the following
   12  *    disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  *
   17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   27  *
   28  * $FreeBSD: releng/12.0/sys/sys/rangelock.h 326256 2017-11-27 15:01:59Z pfg $
   29  */
   30 
   31 #ifndef _SYS_RANGELOCK_H
   32 #define _SYS_RANGELOCK_H
   33 
   34 #include <sys/queue.h>
   35 
   36 #define RL_LOCK_READ            0x0001
   37 #define RL_LOCK_WRITE           0x0002
   38 #define RL_LOCK_TYPE_MASK       0x0003
   39 #define RL_LOCK_GRANTED         0x0004
   40 
   41 struct rl_q_entry;
   42 
   43 /*
   44  * The structure representing the range lock.  Caller may request
   45  * read or write access to the range of bytes. Access is granted if
   46  * all existing lock owners are compatible with the request. Two lock
   47  * owners are compatible if their ranges do not overlap, or both
   48  * owners are for read.
   49  *
   50  * Access to the structure itself is synchronized with the externally
   51  * supplied mutex.
   52  *
   53  * rl_waiters is the queue containing in order (a) granted write lock
   54  * requests, (b) granted read lock requests, and (c) in order of arrival,
   55  * lock requests which cannot be granted yet.
   56  *
   57  * rl_currdep is the first lock request that cannot be granted now due
   58  * to the preceding requests conflicting with it (i.e., it points to
   59  * position (c) in the list above).
   60  */
   61 struct rangelock {
   62         TAILQ_HEAD(, rl_q_entry) rl_waiters;
   63         struct rl_q_entry       *rl_currdep;
   64 };
   65 
   66 #ifdef _KERNEL
   67 
   68 struct mtx;
   69 
   70 void     rangelock_init(struct rangelock *lock);
   71 void     rangelock_destroy(struct rangelock *lock);
   72 void     rangelock_unlock(struct rangelock *lock, void *cookie,
   73             struct mtx *ilk);
   74 void    *rangelock_unlock_range(struct rangelock *lock, void *cookie,
   75             off_t start, off_t end, struct mtx *ilk);
   76 void    *rangelock_rlock(struct rangelock *lock, off_t start, off_t end,
   77             struct mtx *ilk);
   78 void    *rangelock_wlock(struct rangelock *lock, off_t start, off_t end,
   79             struct mtx *ilk);
   80 void     rlqentry_free(struct rl_q_entry *rlqe);
   81 
   82 #endif  /* _KERNEL */
   83 
   84 #endif  /* _SYS_RANGELOCK_H */

Cache object: 4b5f5874fd78c2b33d277e01ec330feb


[ source navigation ] [ diff markup ] [ identifier search ] [ freetext search ] [ file search ] [ list types ] [ track identifier ]


This page is part of the FreeBSD/Linux Linux Kernel Cross-Reference, and was automatically generated using a modified version of the LXR engine.