freebsd-nq/sys/i386/include/pmap.h
John Dyson 3eb77c8302 Fix a problem with tracking the modified bit. Eliminate the
ugly inline-asm code, and speed up the page-table-page tracking.
1996-02-25 03:02:53 +00:00

205 lines
6.9 KiB
C

/*
* Copyright (c) 1991 Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* the Systems Programming Group of the University of Utah Computer
* Science Department and William Jolitz of UUNET Technologies Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* Derived from hp300 version by Mike Hibler, this version by William
* Jolitz uses a recursive map [a pde points to the page directory] to
* map the page tables using the pagetables themselves. This is done to
* reduce the impact on kernel virtual memory for lots of sparse address
* space, and to reduce the cost of memory to each process.
*
* from: hp300: @(#)pmap.h 7.2 (Berkeley) 12/16/90
* from: @(#)pmap.h 7.4 (Berkeley) 5/12/91
* $Id: pmap.h,v 1.33 1996/02/04 21:20:53 davidg Exp $
*/
#ifndef _MACHINE_PMAP_H_
#define _MACHINE_PMAP_H_
#include <machine/pte.h>
typedef unsigned int *pd_entry_t;
typedef unsigned int *pt_entry_t;
/*
* NKPDE controls the virtual space of the kernel, what ever is left, minus
* the alternate page table area is given to the user (NUPDE)
*/
/*
* NKPDE controls the virtual space of the kernel, what ever is left is
* given to the user (NUPDE)
*/
#ifndef NKPT
#if 0
#define NKPT 26 /* actual number of kernel page tables */
#else
#define NKPT 9 /* actual number of kernel page tables */
#endif
#endif
#ifndef NKPDE
#define NKPDE 63 /* addressable number of page tables/pde's */
#endif
#define NUPDE (NPTEPG-NKPDE) /* number of user pde's */
/*
* The *PTDI values control the layout of virtual memory
*
* XXX This works for now, but I am not real happy with it, I'll fix it
* right after I fix locore.s and the magic 28K hole
*/
#define APTDPTDI (NPTEPG-1) /* alt ptd entry that points to APTD */
#define KPTDI (APTDPTDI-NKPDE)/* start of kernel virtual pde's */
#define PTDPTDI (KPTDI-1) /* ptd entry that points to ptd! */
#define KSTKPTDI (PTDPTDI-1) /* ptd entry for u./kernel&user stack */
#define KSTKPTEOFF (NBPG/sizeof(pd_entry_t)-UPAGES) /* pte entry for kernel stack */
#define PDESIZE sizeof(pd_entry_t) /* for assembly files */
#define PTESIZE sizeof(pt_entry_t) /* for assembly files */
/*
* Address of current and alternate address space page table maps
* and directories.
*/
#ifdef KERNEL
extern pt_entry_t PTmap[], APTmap[], Upte;
extern pd_entry_t PTD[], APTD[], PTDpde, APTDpde, Upde;
extern int IdlePTD; /* physical address of "Idle" state directory */
#endif
/*
* virtual address to page table entry and
* to physical address. Likewise for alternate address space.
* Note: these work recursively, thus vtopte of a pte will give
* the corresponding pde that in turn maps it.
*/
#define vtopte(va) (PTmap + i386_btop(va))
#define kvtopte(va) vtopte(va)
#define ptetov(pt) (i386_ptob(pt - PTmap))
#define vtophys(va) (((int) (*vtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET))
#define ispt(va) ((va) >= UPT_MIN_ADDRESS && (va) <= KPT_MAX_ADDRESS)
#define avtopte(va) (APTmap + i386_btop(va))
#define ptetoav(pt) (i386_ptob(pt - APTmap))
#define avtophys(va) (((int) (*avtopte(va))&PG_FRAME) | ((int)(va) & PGOFSET))
#ifdef KERNEL
/*
* Routine: pmap_kextract
* Function:
* Extract the physical page address associated
* kernel virtual address.
*/
static __inline vm_offset_t
pmap_kextract(vm_offset_t va)
{
vm_offset_t pa = *(int *)vtopte(va);
pa = (pa & PG_FRAME) | (va & ~PG_FRAME);
return pa;
}
#endif
/*
* macros to generate page directory/table indices
*/
#define pdei(va) (((va)&PD_MASK)>>PD_SHIFT)
#define ptei(va) (((va)&PT_MASK)>>PG_SHIFT)
/*
* Pmap stuff
*/
struct pmap {
pd_entry_t *pm_pdir; /* KVA of page directory */
boolean_t pm_pdchanged; /* pdir changed */
short pm_dref; /* page directory ref count */
short pm_count; /* pmap reference count */
struct pmap_statistics pm_stats; /* pmap statistics */
long pm_ptpages; /* more stats: PT pages */
};
typedef struct pmap *pmap_t;
#ifdef KERNEL
extern pmap_t kernel_pmap;
#endif
/*
* For each vm_page_t, there is a list of all currently valid virtual
* mappings of that page. An entry is a pv_entry_t, the list is pv_table.
*/
typedef struct pv_entry {
struct pv_entry *pv_next; /* next pv_entry */
pmap_t pv_pmap; /* pmap where mapping lies */
vm_offset_t pv_va; /* virtual address for mapping */
vm_page_t pv_ptem; /* VM page for pte */
} *pv_entry_t;
#define PV_ENTRY_NULL ((pv_entry_t) 0)
#define PV_CI 0x01 /* all entries must be cache inhibited */
#define PV_PTPAGE 0x02 /* entry maps a page table page */
#ifdef KERNEL
extern caddr_t CADDR1;
extern pt_entry_t *CMAP1;
extern vm_offset_t avail_end;
extern vm_offset_t avail_start;
extern vm_offset_t phys_avail[];
extern pv_entry_t pv_table; /* array of entries, one per page */
extern vm_offset_t virtual_avail;
extern vm_offset_t virtual_end;
#define pa_index(pa) atop(pa - vm_first_phys)
#define pa_to_pvh(pa) (&pv_table[pa_index(pa)])
#define pmap_resident_count(pmap) ((pmap)->pm_stats.resident_count)
struct pcb;
void pmap_bootstrap __P(( vm_offset_t, vm_offset_t));
pmap_t pmap_kernel __P((void));
void *pmap_mapdev __P((vm_offset_t, vm_size_t));
pt_entry_t * __pure pmap_pte __P((pmap_t, vm_offset_t)) __pure2;
void pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t));
vm_page_t pmap_use_pt __P((pmap_t, vm_offset_t));
#endif /* KERNEL */
#endif /* !_MACHINE_PMAP_H_ */