pmap.h revision 9578
1/*
2 * Copyright (c) 1991 Regents of the University of California.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * the Systems Programming Group of the University of Utah Computer
7 * Science Department and William Jolitz of UUNET Technologies Inc.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 3. All advertising materials mentioning features or use of this software
18 *    must display the following acknowledgement:
19 *	This product includes software developed by the University of
20 *	California, Berkeley and its contributors.
21 * 4. Neither the name of the University nor the names of its contributors
22 *    may be used to endorse or promote products derived from this software
23 *    without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * Derived from hp300 version by Mike Hibler, this version by William
38 * Jolitz uses a recursive map [a pde points to the page directory] to
39 * map the page tables using the pagetables themselves. This is done to
40 * reduce the impact on kernel virtual memory for lots of sparse address
41 * space, and to reduce the cost of memory to each process.
42 *
43 *	from: hp300: @(#)pmap.h	7.2 (Berkeley) 12/16/90
44 *	from: @(#)pmap.h	7.4 (Berkeley) 5/12/91
45 * 	$Id: pmap.h,v 1.27 1995/07/13 08:47:33 davidg Exp $
46 */
47
48#ifndef _MACHINE_PMAP_H_
49#define	_MACHINE_PMAP_H_
50
51#include <machine/pte.h>
52
53typedef unsigned int *pd_entry_t;
54typedef unsigned int *pt_entry_t;
55
56/*
57 * NKPDE controls the virtual space of the kernel, what ever is left, minus
58 * the alternate page table area is given to the user (NUPDE)
59 */
60/*
61 * NKPDE controls the virtual space of the kernel, what ever is left is
62 * given to the user (NUPDE)
63 */
64#ifndef NKPT
65#if 0
66#define	NKPT			26	/* actual number of kernel page tables */
67#else
68#define	NKPT			9	/* actual number of kernel page tables */
69#endif
70#endif
71#ifndef NKPDE
72#define NKPDE			63	/* addressable number of page tables/pde's */
73#endif
74
75#define	NUPDE		(NPTEPG-NKPDE)	/* number of user pde's */
76
77/*
78 * The *PTDI values control the layout of virtual memory
79 *
80 * XXX This works for now, but I am not real happy with it, I'll fix it
81 * right after I fix locore.s and the magic 28K hole
82 */
83#define	APTDPTDI	(NPTEPG-1)	/* alt ptd entry that points to APTD */
84#define	KPTDI		(APTDPTDI-NKPDE)/* start of kernel virtual pde's */
85#define	PTDPTDI		(KPTDI-1)	/* ptd entry that points to ptd! */
86#define	KSTKPTDI	(PTDPTDI-1)	/* ptd entry for u./kernel&user stack */
87#define KSTKPTEOFF	(NBPG/sizeof(pd_entry_t)-UPAGES) /* pte entry for kernel stack */
88
89#define PDESIZE		sizeof(pd_entry_t) /* for assembly files */
90#define PTESIZE		sizeof(pt_entry_t) /* for assembly files */
91
92/*
93 * Address of current and alternate address space page table maps
94 * and directories.
95 */
96#ifdef KERNEL
97extern pt_entry_t PTmap[], APTmap[], Upte;
98extern pd_entry_t PTD[], APTD[], PTDpde, APTDpde, Upde;
99
100extern int	IdlePTD;	/* physical address of "Idle" state directory */
101#endif
102
103/*
104 * virtual address to page table entry and
105 * to physical address. Likewise for alternate address space.
106 * Note: these work recursively, thus vtopte of a pte will give
107 * the corresponding pde that in turn maps it.
108 */
109#define	vtopte(va)	(PTmap + i386_btop(va))
110#define	kvtopte(va)	vtopte(va)
111#define	ptetov(pt)	(i386_ptob(pt - PTmap))
112#define	vtophys(va)	(((int) (*vtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET))
113#define	ispt(va)	((va) >= UPT_MIN_ADDRESS && (va) <= KPT_MAX_ADDRESS)
114
115#define	avtopte(va)	(APTmap + i386_btop(va))
116#define	ptetoav(pt)	(i386_ptob(pt - APTmap))
117#define	avtophys(va)	(((int) (*avtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET))
118
119#ifdef KERNEL
120/*
121 *	Routine:	pmap_kextract
122 *	Function:
123 *		Extract the physical page address associated
124 *		kernel virtual address.
125 */
126static __inline vm_offset_t
127pmap_kextract(vm_offset_t va)
128{
129	vm_offset_t pa = *(int *)vtopte(va);
130	pa = (pa & PG_FRAME) | (va & ~PG_FRAME);
131	return pa;
132}
133#endif
134
135/*
136 * macros to generate page directory/table indicies
137 */
138
139#define	pdei(va)	(((va)&PD_MASK)>>PD_SHIFT)
140#define	ptei(va)	(((va)&PT_MASK)>>PG_SHIFT)
141
142/*
143 * Pmap stuff
144 */
145
146struct pmap {
147	pd_entry_t		*pm_pdir;	/* KVA of page directory */
148	boolean_t		pm_pdchanged;	/* pdir changed */
149	short			pm_dref;	/* page directory ref count */
150	short			pm_count;	/* pmap reference count */
151	struct pmap_statistics	pm_stats;	/* pmap statistics */
152	long			pm_ptpages;	/* more stats: PT pages */
153};
154
155typedef struct pmap	*pmap_t;
156
157#ifdef KERNEL
158extern pmap_t		kernel_pmap;
159#endif
160
161/*
162 * Macros for speed
163 */
164#define	PMAP_ACTIVATE(pmapp, pcbp) \
165	if ((pmapp) != NULL /*&& (pmapp)->pm_pdchanged */) {  \
166		(pcbp)->pcb_cr3 = \
167		    pmap_extract(kernel_pmap, (vm_offset_t)(pmapp)->pm_pdir); \
168		if ((pmapp) == &curproc->p_vmspace->vm_pmap) \
169			load_cr3((pcbp)->pcb_cr3); \
170		(pmapp)->pm_pdchanged = FALSE; \
171	}
172
173#define	PMAP_DEACTIVATE(pmapp, pcbp)
174
175/*
176 * For each vm_page_t, there is a list of all currently valid virtual
177 * mappings of that page.  An entry is a pv_entry_t, the list is pv_table.
178 */
179typedef struct pv_entry {
180	struct pv_entry	*pv_next;	/* next pv_entry */
181	pmap_t		pv_pmap;	/* pmap where mapping lies */
182	vm_offset_t	pv_va;		/* virtual address for mapping */
183} *pv_entry_t;
184
185#define	PV_ENTRY_NULL	((pv_entry_t) 0)
186
187#define	PV_CI		0x01	/* all entries must be cache inhibited */
188#define	PV_PTPAGE	0x02	/* entry maps a page table page */
189
190#ifdef	KERNEL
191
192extern caddr_t	CADDR1;
193extern pt_entry_t *CMAP1;
194extern vm_offset_t avail_end;
195extern vm_offset_t avail_start;
196extern vm_offset_t phys_avail[];
197extern pv_entry_t pv_table;	/* array of entries, one per page */
198extern vm_offset_t virtual_avail;
199extern vm_offset_t virtual_end;
200
201#define	pa_index(pa)		atop(pa - vm_first_phys)
202#define	pa_to_pvh(pa)		(&pv_table[pa_index(pa)])
203
204#define	pmap_resident_count(pmap)	((pmap)->pm_stats.resident_count)
205
206struct pcb;
207
208void	pmap_activate __P((pmap_t, struct pcb *));
209pmap_t	pmap_kernel __P((void));
210boolean_t pmap_page_exists __P((pmap_t, vm_offset_t));
211pt_entry_t *pmap_pte __P((pmap_t, vm_offset_t));
212vm_page_t pmap_pte_vm_page __P((pmap_t, vm_offset_t));
213void	*pmap_mapdev __P((vm_offset_t, vm_size_t));
214void	pmap_growkernel __P((vm_offset_t));
215void	pmap_bootstrap __P(( vm_offset_t, vm_offset_t));
216void	pmap_use_pt __P((pmap_t, vm_offset_t));
217void	pmap_unuse_pt __P((pmap_t, vm_offset_t));
218
219#endif /* KERNEL */
220
221#endif /* !_MACHINE_PMAP_H_ */
222