xref: /titanic_41/usr/src/uts/common/sys/nbmlock.h (revision fd9cb95cbb2f626355a60efb9d02c5f0a33c10e6)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright (c) 2001 by Sun Microsystems, Inc.
24  * All rights reserved.
25  */
26 
27 #ifndef _NBMLOCK_H
28 #define	_NBMLOCK_H
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * Non-blocking mandatory locking support.
34  */
35 
36 #ifdef __cplusplus
37 extern "C" {
38 #endif
39 
40 #include <sys/vnode.h>
41 #include <sys/rwlock.h>
42 #include <sys/cred.h>
43 
44 /*
45  * Type of operation; used when checking for lock/share conflict.
46  * NBL_READWRITE is used for checking for a conflict with an exclusive lock
47  * (F_WRLCK) or a read-write mmap request.  For checking an actual I/O
48  * request, use NBL_READ or NBL_WRITE.
49  */
50 typedef enum {NBL_READ, NBL_WRITE, NBL_RENAME, NBL_REMOVE,
51 	    NBL_READWRITE} nbl_op_t;
52 
53 /* critical region primitives */
54 extern void nbl_start_crit(vnode_t *, krw_t);
55 extern void nbl_end_crit(vnode_t *);
56 extern int nbl_in_crit(vnode_t *);
57 
58 /* conflict checking */
59 extern int nbl_need_check(vnode_t *);
60 extern int nbl_conflict(vnode_t *, nbl_op_t, u_offset_t, ssize_t, int);
61 extern int nbl_share_conflict(vnode_t *, nbl_op_t);
62 extern int nbl_lock_conflict(vnode_t *, nbl_op_t, u_offset_t, ssize_t, int);
63 extern int nbl_svmand(vnode_t *, cred_t *, int *);
64 
65 extern nbl_op_t nbl_lock_to_op(int);
66 
67 #ifdef __cplusplus
68 }
69 #endif
70 
71 #endif /* _NBMLOCK_H */
72