pte.h revision 1.1 
1/*-
2 * Copyright (c) 1990 The Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following 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 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 *
36 *	@(#)pte.h	5.5 (Berkeley) 5/9/91
37 */
38
39/*
40 * 386 page table entry and page table directory
41 * W.Jolitz, 8/89
42 *
43 * There are two major kinds of pte's: those which have ever existed (and are
44 * thus either now in core or on the swap device), and those which have
45 * never existed, but which will be filled on demand at first reference.
46 * There is a structure describing each.  There is also an ancillary
47 * structure used in page clustering.
48 */
49
50#ifndef LOCORE
51struct pde
52{
53unsigned int
54		pd_v:1,			/* valid bit */
55		pd_prot:2,		/* access control */
56		pd_mbz1:2,		/* reserved, must be zero */
57		pd_u:1,			/* hardware maintained 'used' bit */
58		:1,			/* not used */
59		pd_mbz2:2,		/* reserved, must be zero */
60		:3,			/* reserved for software */
61		pd_pfnum:20;		/* physical page frame number of pte's*/
62};
63struct pte
64{
65unsigned int
66		pg_v:1,			/* valid bit */
67		pg_prot:2,		/* access control */
68		pg_mbz1:2,		/* reserved, must be zero */
69		pg_u:1,			/* hardware maintained 'used' bit */
70		pg_m:1,			/* hardware maintained modified bit */
71		pg_mbz2:2,		/* reserved, must be zero */
72		pg_fod:1,		/* is fill on demand (=0) */
73		:1,			/* must write back to swap (unused) */
74		pg_nc:1,		/* 'uncacheable page' bit */
75		pg_pfnum:20;		/* physical page frame number */
76};
77struct hpte
78{
79unsigned int
80		pg_high:12,		/* special for clustering */
81		pg_pfnum:20;
82};
83struct fpte
84{
85unsigned int
86		pg_v:1,			/* valid bit */
87		pg_prot:2,		/* access control */
88		:5,
89		pg_fileno:1,		/* file mapped from or TEXT or ZERO */
90		pg_fod:1,		/* is fill on demand (=1) */
91		pg_blkno:22;		/* file system block number */
92};
93#endif
94
95#define	PD_MASK		0xffc00000	/* page directory address bits */
96#define	PD_SHIFT	22		/* page directory address bits */
97
98#define	PG_V		0x00000001
99#define	PG_PROT		0x00000006 /* all protection bits . */
100#define	PG_FOD		0x00000200
101#define	PG_SWAPM	0x00000400
102#define PG_N		0x00000800 /* Non-cacheable */
103#define	PG_M		0x00000040
104#define PG_U		0x00000020 /* not currently used */
105#define	PG_FRAME	0xfffff000
106
107#define	PG_FZERO	0
108#define	PG_FTEXT	1
109#define	PG_FMAX		(PG_FTEXT)
110
111#define	PG_NOACC	0
112#define	PG_KR		0x00000000
113#define	PG_KW		0x00000002
114#define	PG_URKR		0x00000004
115#define	PG_URKW		0x00000004
116#define	PG_UW		0x00000006
117
118/*
119 * Page Protection Exception bits
120 */
121
122#define PGEX_P		0x01	/* Protection violation vs. not present */
123#define PGEX_W		0x02	/* during a Write cycle */
124#define PGEX_U		0x04	/* access from User mode (UPL) */
125
126/*
127 * Pte related macros
128 */
129#define	dirty(pte)	((pte)->pg_m)
130
131#ifndef LOCORE
132#ifdef KERNEL
133/* utilities defined in pmap.c */
134extern	struct pte *Sysmap;
135#endif
136#endif
137