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/lockf.h

Version: -  FREEBSD  -  FREEBSD-12-STABLE  -  FREEBSD-12-0  -  FREEBSD-11-STABLE  -  FREEBSD-11-2  -  FREEBSD-11-1  -  FREEBSD-11-0  -  FREEBSD-10-STABLE  -  FREEBSD-10-4  -  FREEBSD-10-3  -  FREEBSD-10-2  -  FREEBSD-10-1  -  FREEBSD-10-0  -  FREEBSD-9-STABLE  -  FREEBSD-9-3  -  FREEBSD-9-2  -  FREEBSD-9-1  -  FREEBSD-9-0  -  FREEBSD-8-STABLE  -  FREEBSD-8-4  -  FREEBSD-8-3  -  FREEBSD-8-2  -  FREEBSD-8-1  -  FREEBSD-8-0  -  FREEBSD-7-STABLE  -  FREEBSD-7-4  -  FREEBSD-7-3  -  FREEBSD-7-2  -  FREEBSD-7-1  -  FREEBSD-7-0  -  FREEBSD-6-STABLE  -  FREEBSD-6-4  -  FREEBSD-6-3  -  FREEBSD-6-2  -  FREEBSD-6-1  -  FREEBSD-6-0  -  FREEBSD-5-STABLE  -  FREEBSD-5-5  -  FREEBSD-5-4  -  FREEBSD-5-3  -  FREEBSD-5-2  -  FREEBSD-5-1  -  FREEBSD-5-0  -  FREEBSD-4-STABLE  -  FREEBSD-3-STABLE  -  FREEBSD22  -  linux-2.6  -  linux-2.4.22  -  MK83  -  MK84  -  PLAN9  -  DFBSD  -  NETBSD  -  NETBSD5  -  NETBSD4  -  NETBSD3  -  NETBSD20  -  OPENBSD  -  xnu-517  -  xnu-792  -  xnu-792.6.70  -  xnu-1228  -  xnu-1456.1.26  -  xnu-1699.24.8  -  xnu-2050.18.24  -  OPENSOLARIS  -  minix-3-1-1 
SearchContext: -  none  -  3  -  10 

    1 /*-
    2  * SPDX-License-Identifier: BSD-3-Clause
    3  *
    4  * Copyright (c) 1991, 1993
    5  *      The Regents of the University of California.  All rights reserved.
    6  *
    7  * This code is derived from software contributed to Berkeley by
    8  * Scooter Morris at Genentech Inc.
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 3. Neither the name of the University nor the names of its contributors
   19  *    may be used to endorse or promote products derived from this software
   20  *    without specific prior written permission.
   21  *
   22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   32  * SUCH DAMAGE.
   33  *
   34  *      @(#)lockf.h     8.1 (Berkeley) 6/11/93
   35  * $FreeBSD: releng/12.0/sys/sys/lockf.h 326023 2017-11-20 19:43:44Z pfg $
   36  */
   37 
   38 #ifndef _SYS_LOCKF_H_
   39 #define _SYS_LOCKF_H_
   40 
   41 #include <sys/queue.h>
   42 #include <sys/_lock.h>
   43 #include <sys/_sx.h>
   44 
   45 struct flock;
   46 struct vop_advlock_args;
   47 struct vop_advlockasync_args;
   48 
   49 /*
   50  * The lockf_entry structure is a kernel structure which contains the
   51  * information associated with a byte range lock.  The lockf_entry
   52  * structures are linked into the inode structure. Locks are sorted by
   53  * the starting byte of the lock for efficiency.
   54  *
   55  * Active and pending locks on a vnode are organised into a
   56  * graph. Each pending lock has an out-going edge to each active lock
   57  * that blocks it.
   58  *
   59  * Locks:
   60  * (i)          locked by the vnode interlock
   61  * (s)          locked by state->ls_lock
   62  * (S)          locked by lf_lock_states_lock
   63  * (c)          const until freeing
   64  */
   65 struct lockf_edge {
   66         LIST_ENTRY(lockf_edge) le_outlink; /* (s) link from's out-edge list */
   67         LIST_ENTRY(lockf_edge) le_inlink; /* (s) link to's in-edge list */
   68         struct lockf_entry *le_from;    /* (c) out-going from here */
   69         struct lockf_entry *le_to;      /* (s) in-coming to here */
   70 };
   71 LIST_HEAD(lockf_edge_list, lockf_edge);
   72 
   73 struct lockf_entry {
   74         short   lf_flags;           /* (c) Semantics: F_POSIX, F_FLOCK, F_WAIT */
   75         short   lf_type;            /* (s) Lock type: F_RDLCK, F_WRLCK */
   76         off_t   lf_start;           /* (s) Byte # of the start of the lock */
   77         off_t   lf_end;             /* (s) Byte # of the end of the lock (OFF_MAX=EOF) */
   78         struct  lock_owner *lf_owner; /* (c) Owner of the lock */
   79         struct  vnode *lf_vnode;    /* (c) File being locked (only valid for active lock) */
   80         struct  inode *lf_inode;    /* (c) Back pointer to the inode */
   81         struct  task *lf_async_task;/* (c) Async lock callback */
   82         LIST_ENTRY(lockf_entry) lf_link;  /* (s) Linkage for lock lists */
   83         struct lockf_edge_list lf_outedges; /* (s) list of out-edges */
   84         struct lockf_edge_list lf_inedges; /* (s) list of out-edges */
   85         int     lf_refs;            /* (s) ref count */
   86 };
   87 LIST_HEAD(lockf_entry_list, lockf_entry);
   88 
   89 /*
   90  * Extra lf_flags bits used by the implementation
   91  */
   92 #define F_INTR          0x8000  /* lock was interrupted by lf_purgelocks */
   93 
   94 /*
   95  * Filesystem private node structures should include space for a
   96  * pointer to a struct lockf_state. This pointer is used by the lock
   97  * manager to track the locking state for a file.
   98  *
   99  * The ls_active list contains the set of active locks on the file. It
  100  * is strictly ordered by the lock's lf_start value. Each active lock
  101  * will have in-coming edges to any pending lock which it blocks.
  102  *
  103  * Lock requests which are blocked by some other active lock are
  104  * listed in ls_pending with newer requests first in the list. Lock
  105  * requests in this list will have out-going edges to each active lock
  106  * that blocks then. They will also have out-going edges to each
  107  * pending lock that is older in the queue - this helps to ensure
  108  * fairness when several processes are contenting to lock the same
  109  * record.
  110 
  111  * The value of ls_threads is the number of threads currently using
  112  * the state structure (typically either setting/clearing locks or
  113  * sleeping waiting to do so). This is used to defer freeing the
  114  * structure while some thread is still using it.
  115  */
  116 struct lockf {
  117         LIST_ENTRY(lockf) ls_link;      /* (S) all active lockf states */
  118         struct  sx      ls_lock;
  119         struct  lockf_entry_list ls_active; /* (s) Active locks */
  120         struct  lockf_entry_list ls_pending; /* (s) Pending locks */
  121         int             ls_threads;     /* (i) Thread count */
  122 };
  123 LIST_HEAD(lockf_list, lockf);
  124 
  125 typedef int lf_iterator(struct vnode *, struct flock *, void *);
  126 
  127 int      lf_advlock(struct vop_advlock_args *, struct lockf **, u_quad_t);
  128 int      lf_advlockasync(struct vop_advlockasync_args *, struct lockf **, u_quad_t);
  129 void     lf_purgelocks(struct vnode *vp, struct lockf **statep);
  130 int      lf_iteratelocks_sysid(int sysid, lf_iterator *, void *);
  131 int      lf_iteratelocks_vnode(struct vnode *vp, lf_iterator *, void *);
  132 int      lf_countlocks(int sysid);
  133 void     lf_clearremotesys(int sysid);
  134 
  135 #endif /* !_SYS_LOCKF_H_ */

Cache object: 7ccdf25bb04a777afa2150072f63a496


[ 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.