4.4BSD/usr/src/sys/i386/include/pmap.h
/*
* Copyright (c) 1991, 1993
* The 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.
*
* @(#)pmap.h 8.1 (Berkeley) 6/11/93
*/
/*
* 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
*/
#ifndef _PMAP_MACHINE_
#define _PMAP_MACHINE_ 1
/*
* 386 page table entry and page table directory
* W.Jolitz, 8/89
*/
struct pde
{
unsigned int
pd_v:1, /* valid bit */
pd_prot:2, /* access control */
pd_mbz1:2, /* reserved, must be zero */
pd_u:1, /* hardware maintained 'used' bit */
:1, /* not used */
pd_mbz2:2, /* reserved, must be zero */
:3, /* reserved for software */
pd_pfnum:20; /* physical page frame number of pte's*/
};
#define PD_MASK 0xffc00000 /* page directory address bits */
#define PT_MASK 0x003ff000 /* page table address bits */
#define PD_SHIFT 22 /* page directory address shift */
#define PG_SHIFT 12 /* page table address shift */
struct pte
{
unsigned int
pg_v:1, /* valid bit */
pg_prot:2, /* access control */
pg_mbz1:2, /* reserved, must be zero */
pg_u:1, /* hardware maintained 'used' bit */
pg_m:1, /* hardware maintained modified bit */
pg_mbz2:2, /* reserved, must be zero */
pg_w:1, /* software, wired down page */
:1, /* software (unused) */
pg_nc:1, /* 'uncacheable page' bit */
pg_pfnum:20; /* physical page frame number */
};
#define PG_V 0x00000001
#define PG_RO 0x00000000
#define PG_RW 0x00000002
#define PG_u 0x00000004
#define PG_PROT 0x00000006 /* all protection bits . */
#define PG_W 0x00000200
#define PG_N 0x00000800 /* Non-cacheable */
#define PG_M 0x00000040
#define PG_U 0x00000020
#define PG_FRAME 0xfffff000
#define PG_NOACC 0
#define PG_KR 0x00000000
#define PG_KW 0x00000002
#define PG_URKR 0x00000004
#define PG_URKW 0x00000004
#define PG_UW 0x00000006
/* Garbage for current bastardized pager that assumes a hp300 */
#define PG_NV 0
#define PG_CI 0
/*
* Page Protection Exception bits
*/
#define PGEX_P 0x01 /* Protection violation vs. not present */
#define PGEX_W 0x02 /* during a Write cycle */
#define PGEX_U 0x04 /* access from User mode (UPL) */
typedef struct pde pd_entry_t; /* page directory entry */
typedef struct pte pt_entry_t; /* Mach page table entry */
/*
* One page directory, shared between
* kernel and user modes.
*/
#define I386_PAGE_SIZE NBPG
#define I386_PDR_SIZE NBPDR
#define I386_KPDES 8 /* KPT page directory size */
#define I386_UPDES NBPDR/sizeof(struct pde)-8 /* UPT page directory size */
#define UPTDI 0x3f6 /* ptd entry for u./kernel&user stack */
#define PTDPTDI 0x3f7 /* ptd entry that points to ptd! */
#define KPTDI_FIRST 0x3f8 /* start of kernel virtual pde's */
#define KPTDI_LAST 0x3fA /* last of kernel virtual pde's */
/*
* Address of current and alternate address space page table maps
* and directories.
*/
#ifdef KERNEL
extern struct pte PTmap[], APTmap[], Upte;
extern struct pde PTD[], APTD[], PTDpde, APTDpde, Upde;
extern pt_entry_t *Sysmap;
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) (i386_ptob(vtopte(va)->pg_pfnum) | ((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) (i386_ptob(avtopte(va)->pg_pfnum) | ((int)(va) & PGOFSET))
/*
* macros to generate page directory/table indicies
*/
#define pdei(va) (((va)&PD_MASK)>>PD_SHIFT)
#define ptei(va) (((va)&PT_MASK)>>PT_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 */
simple_lock_data_t pm_lock; /* lock on pmap */
struct pmap_statistics pm_stats; /* pmap statistics */
long pm_ptpages; /* more stats: PT pages */
};
typedef struct pmap *pmap_t;
#ifdef KERNEL
extern struct pmap kernel_pmap_store;
#define kernel_pmap (&kernel_pmap_store)
#endif
/*
* Macros for speed
*/
#define PMAP_ACTIVATE(pmapp, pcbp) \
if ((pmapp) != NULL /*&& (pmapp)->pm_pdchanged */) { \
(pcbp)->pcb_cr3 = \
pmap_extract(kernel_pmap, (pmapp)->pm_pdir); \
if ((pmapp) == &curproc->p_vmspace->vm_pmap) \
load_cr3((pcbp)->pcb_cr3); \
(pmapp)->pm_pdchanged = FALSE; \
}
#define PMAP_DEACTIVATE(pmapp, pcbp)
/*
* 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 */
int pv_flags; /* flags */
} *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
pv_entry_t pv_table; /* array of entries, one per page */
#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)
#define pmap_wired_count(pmap) ((pmap)->pm_stats.wired_count)
#endif KERNEL
#endif _PMAP_MACHINE_