xref: /titanic_41/usr/src/uts/common/vm/vpage.h (revision 45916cd2fec6e79bca5dee0421bd39e3c2910d1e)
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 1998 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * University Copyright- Copyright (c) 1982, 1986, 1988
32  * The Regents of the University of California
33  * All Rights Reserved
34  *
35  * University Acknowledgment- Portions of this document are derived from
36  * software developed by the University of California, Berkeley, and its
37  * contributors.
38  */
39 
40 #ifndef	_VM_VPAGE_H
41 #define	_VM_VPAGE_H
42 
43 #pragma ident	"%Z%%M%	%I%	%E% SMI"
44 
45 #ifdef	__cplusplus
46 extern "C" {
47 #endif
48 
49 /*
50  * VM - Information per virtual page.
51  */
52 struct vpage {
53 	uchar_t nvp_prot;	/* see <sys/mman.h> prot flags */
54 	uchar_t nvp_advice;	/* pplock & <sys/mman.h> madvise flags */
55 };
56 
57 /*
58  * This was changed from a bitfield to flags/macros in order
59  * to conserve space (uchar_t bitfields are not ANSI).  This could
60  * have been condensed to a uchar_t, but at the expense of complexity.
61  * We've stolen a bit from the top of nvp_advice to store pplock in.
62  *
63  * WARNING: VPP_SETADVICE(vpp, x) evaluates vpp twice, and VPP_PLOCK(vpp)
64  * returns a positive integer when the lock is held, not necessarily (1).
65  */
66 #define	VP_ADVICE_MASK	(0x07)
67 #define	VP_PPLOCK_MASK	(0x80)	/* physical page locked by me */
68 #define	VP_PPLOCK_SHIFT	(0x07)	/* offset of lock hiding inside nvp_advice */
69 
70 #define	VPP_PROT(vpp)	((vpp)->nvp_prot)
71 #define	VPP_ADVICE(vpp)	((vpp)->nvp_advice & VP_ADVICE_MASK)
72 #define	VPP_ISPPLOCK(vpp) \
73 	((uchar_t)((vpp)->nvp_advice & VP_PPLOCK_MASK))
74 
75 #define	VPP_SETPROT(vpp, x)	((vpp)->nvp_prot = (x))
76 #define	VPP_SETADVICE(vpp, x) \
77 	((vpp)->nvp_advice = ((vpp)->nvp_advice & ~VP_ADVICE_MASK) | \
78 		((x) & VP_ADVICE_MASK))
79 #define	VPP_SETPPLOCK(vpp)	((vpp)->nvp_advice |= VP_PPLOCK_MASK)
80 #define	VPP_CLRPPLOCK(vpp)	((vpp)->nvp_advice &= ~VP_PPLOCK_MASK)
81 
82 #ifdef	__cplusplus
83 }
84 #endif
85 
86 #endif	/* _VM_VPAGE_H */
87