usr/src/uts/common/sys/nbmlock.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25
  26 #ifndef _NBMLOCK_H
  27 #define _NBMLOCK_H
  28
  29 /*
  30  * Non-blocking mandatory locking support.
  31  */
  32
  33 #ifdef __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 #include <sys/vnode.h>
  38 #include <sys/rwlock.h>
  39 #include <sys/cred.h>
  40
  41 /*
  42  * Type of operation; used when checking for lock/share conflict.
  43  * NBL_READWRITE is used for checking for a conflict with an exclusive lock
  44  * (F_WRLCK) or a read-write mmap request.  For checking an actual I/O
  45  * request, use NBL_READ or NBL_WRITE.
  46  */
  47 typedef enum {NBL_READ, NBL_WRITE, NBL_RENAME, NBL_REMOVE,
  48             NBL_READWRITE} nbl_op_t;
  49
  50 /* critical region primitives */
  51 extern void nbl_start_crit(vnode_t *, krw_t);
  52 extern void nbl_end_crit(vnode_t *);
  53 extern int nbl_in_crit(vnode_t *);
  54
  55 /* conflict checking */
  56 extern int nbl_need_check(vnode_t *);
  57 extern int nbl_conflict(vnode_t *, nbl_op_t, u_offset_t, ssize_t, int,
  58     caller_context_t *);
  59 extern int nbl_share_conflict(vnode_t *, nbl_op_t, caller_context_t *);
  60 extern int nbl_lock_conflict(vnode_t *, nbl_op_t, u_offset_t, ssize_t, int,
  61     caller_context_t *);
  62 extern int nbl_svmand(vnode_t *, cred_t *, int *);
  63
  64
  65 #ifdef __cplusplus
  66 }
  67 #endif
  68
  69 #endif /* _NBMLOCK_H */