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freebsd-nq/sys/amd64/amd64/pmap.c
David Greenman 7b0047e213 Made pmap_testbit a static function.
1995-03-30 08:55:39 +00:00

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/*
* Copyright (c) 1991 Regents of the University of California.
* All rights reserved.
* Copyright (c) 1994 John S. Dyson
* All rights reserved.
* Copyright (c) 1994 David Greenman
* 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.
*
* from: @(#)pmap.c 7.7 (Berkeley) 5/12/91
* $Id: pmap.c,v 1.54 1995/03/26 23:42:07 davidg Exp $
*/
/*
* 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.
*
* Derived from: hp300/@(#)pmap.c 7.1 (Berkeley) 12/5/90
*/
/*
* Major modifications by John S. Dyson primarily to support
* pageable page tables, eliminating pmap_attributes,
* discontiguous memory pages, and using more efficient string
* instructions. Jan 13, 1994. Further modifications on Mar 2, 1994,
* general clean-up and efficiency mods.
*/
/*
* Manages physical address maps.
*
* In addition to hardware address maps, this
* module is called upon to provide software-use-only
* maps which may or may not be stored in the same
* form as hardware maps. These pseudo-maps are
* used to store intermediate results from copy
* operations to and from address spaces.
*
* Since the information managed by this module is
* also stored by the logical address mapping module,
* this module may throw away valid virtual-to-physical
* mappings at almost any time. However, invalidations
* of virtual-to-physical mappings must be done as
* requested.
*
* In order to cope with hardware architectures which
* make virtual-to-physical map invalidates expensive,
* this module may delay invalidate or reduced protection
* operations until such time as they are actually
* necessary. This module is given full information as
* to which processors are currently using which maps,
* and to when physical maps must be made correct.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/user.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <i386/isa/isa.h>
/*
* Allocate various and sundry SYSMAPs used in the days of old VM
* and not yet converted. XXX.
*/
#define BSDVM_COMPAT 1
/*
* Get PDEs and PTEs for user/kernel address space
*/
#define pmap_pde(m, v) (&((m)->pm_pdir[((vm_offset_t)(v) >> PD_SHIFT)&1023]))
#define pdir_pde(m, v) (m[((vm_offset_t)(v) >> PD_SHIFT)&1023])
#define pmap_pte_pa(pte) (*(int *)(pte) & PG_FRAME)
#define pmap_pde_v(pte) ((*(int *)pte & PG_V) != 0)
#define pmap_pte_w(pte) ((*(int *)pte & PG_W) != 0)
#define pmap_pte_m(pte) ((*(int *)pte & PG_M) != 0)
#define pmap_pte_u(pte) ((*(int *)pte & PG_U) != 0)
#define pmap_pte_v(pte) ((*(int *)pte & PG_V) != 0)
#define pmap_pte_set_w(pte, v) ((v)?(*(int *)pte |= PG_W):(*(int *)pte &= ~PG_W))
#define pmap_pte_set_prot(pte, v) ((*(int *)pte &= ~PG_PROT), (*(int *)pte |= (v)))
/*
* Given a map and a machine independent protection code,
* convert to a vax protection code.
*/
#define pte_prot(m, p) (protection_codes[p])
int protection_codes[8];
struct pmap kernel_pmap_store;
pmap_t kernel_pmap;
vm_offset_t phys_avail[6]; /* 2 entries + 1 null */
vm_offset_t avail_start; /* PA of first available physical page */
vm_offset_t avail_end; /* PA of last available physical page */
vm_size_t mem_size; /* memory size in bytes */
vm_offset_t virtual_avail; /* VA of first avail page (after kernel bss) */
vm_offset_t virtual_end; /* VA of last avail page (end of kernel AS) */
int i386pagesperpage; /* PAGE_SIZE / I386_PAGE_SIZE */
boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */
vm_offset_t vm_first_phys, vm_last_phys;
static inline int pmap_is_managed();
static void i386_protection_init();
static void pmap_alloc_pv_entry();
static inline pv_entry_t get_pv_entry();
int nkpt;
extern vm_offset_t clean_sva, clean_eva;
extern int cpu_class;
#if BSDVM_COMPAT
#include <sys/msgbuf.h>
/*
* All those kernel PT submaps that BSD is so fond of
*/
pt_entry_t *CMAP1, *CMAP2, *ptmmap;
pv_entry_t pv_table;
caddr_t CADDR1, CADDR2, ptvmmap;
pt_entry_t *msgbufmap;
struct msgbuf *msgbufp;
#endif
void
init_pv_entries(int);
/*
* Routine: pmap_pte
* Function:
* Extract the page table entry associated
* with the given map/virtual_address pair.
* [ what about induced faults -wfj]
*/
inline pt_entry_t * const
pmap_pte(pmap, va)
register pmap_t pmap;
vm_offset_t va;
{
if (pmap && *pmap_pde(pmap, va)) {
vm_offset_t frame = (int) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
/* are we current address space or kernel? */
if ((pmap == kernel_pmap) || (frame == ((int) PTDpde & PG_FRAME)))
return ((pt_entry_t *) vtopte(va));
/* otherwise, we are alternate address space */
else {
if (frame != ((int) APTDpde & PG_FRAME)) {
APTDpde = pmap->pm_pdir[PTDPTDI];
pmap_update();
}
return ((pt_entry_t *) avtopte(va));
}
}
return (0);
}
/*
* Routine: pmap_extract
* Function:
* Extract the physical page address associated
* with the given map/virtual_address pair.
*/
vm_offset_t
pmap_extract(pmap, va)
register pmap_t pmap;
vm_offset_t va;
{
vm_offset_t pa;
if (pmap && *pmap_pde(pmap, va)) {
vm_offset_t frame = (int) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
/* are we current address space or kernel? */
if ((pmap == kernel_pmap)
|| (frame == ((int) PTDpde & PG_FRAME))) {
pa = *(int *) vtopte(va);
/* otherwise, we are alternate address space */
} else {
if (frame != ((int) APTDpde & PG_FRAME)) {
APTDpde = pmap->pm_pdir[PTDPTDI];
pmap_update();
}
pa = *(int *) avtopte(va);
}
return ((pa & PG_FRAME) | (va & ~PG_FRAME));
}
return 0;
}
/*
* determine if a page is managed (memory vs. device)
*/
static inline int
pmap_is_managed(pa)
vm_offset_t pa;
{
int i;
if (!pmap_initialized)
return 0;
for (i = 0; phys_avail[i + 1]; i += 2) {
if (pa >= phys_avail[i] && pa < phys_avail[i + 1])
return 1;
}
return 0;
}
/*
* find the vm_page_t of a pte (only) given va of pte and pmap
*/
__inline vm_page_t
pmap_pte_vm_page(pmap, pt)
pmap_t pmap;
vm_offset_t pt;
{
vm_page_t m;
pt = i386_trunc_page(pt);
pt = (pt - UPT_MIN_ADDRESS) / NBPG;
pt = ((vm_offset_t) pmap->pm_pdir[pt]) & PG_FRAME;
m = PHYS_TO_VM_PAGE(pt);
return m;
}
/*
* Wire a page table page
*/
__inline void
pmap_use_pt(pmap, va)
pmap_t pmap;
vm_offset_t va;
{
vm_offset_t pt;
if ((va >= UPT_MIN_ADDRESS) || !pmap_initialized)
return;
pt = (vm_offset_t) vtopte(va);
vm_page_hold(pmap_pte_vm_page(pmap, pt));
}
/*
* Unwire a page table page
*/
inline void
pmap_unuse_pt(pmap, va)
pmap_t pmap;
vm_offset_t va;
{
vm_offset_t pt;
vm_page_t m;
if ((va >= UPT_MIN_ADDRESS) || !pmap_initialized)
return;
pt = (vm_offset_t) vtopte(va);
m = pmap_pte_vm_page(pmap, pt);
vm_page_unhold(m);
if (pmap != kernel_pmap &&
(m->hold_count == 0) &&
(m->wire_count == 0) &&
(va < KPT_MIN_ADDRESS)) {
pmap_page_protect(VM_PAGE_TO_PHYS(m), VM_PROT_NONE);
vm_page_free(m);
}
}
/* [ macro again?, should I force kstack into user map here? -wfj ] */
void
pmap_activate(pmap, pcbp)
register pmap_t pmap;
struct pcb *pcbp;
{
PMAP_ACTIVATE(pmap, pcbp);
}
/*
* Bootstrap the system enough to run with virtual memory.
* Map the kernel's code and data, and allocate the system page table.
*
* On the I386 this is called after mapping has already been enabled
* and just syncs the pmap module with what has already been done.
* [We can't call it easily with mapping off since the kernel is not
* mapped with PA == VA, hence we would have to relocate every address
* from the linked base (virtual) address "KERNBASE" to the actual
* (physical) address starting relative to 0]
*/
#define DMAPAGES 8
void
pmap_bootstrap(firstaddr, loadaddr)
vm_offset_t firstaddr;
vm_offset_t loadaddr;
{
#if BSDVM_COMPAT
vm_offset_t va;
pt_entry_t *pte;
#endif
avail_start = firstaddr + DMAPAGES * NBPG;
virtual_avail = (vm_offset_t) KERNBASE + avail_start;
virtual_end = VM_MAX_KERNEL_ADDRESS;
i386pagesperpage = PAGE_SIZE / NBPG;
/*
* Initialize protection array.
*/
i386_protection_init();
/*
* The kernel's pmap is statically allocated so we don't have to use
* pmap_create, which is unlikely to work correctly at this part of
* the boot sequence.
*/
kernel_pmap = &kernel_pmap_store;
kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + IdlePTD);
simple_lock_init(&kernel_pmap->pm_lock);
kernel_pmap->pm_count = 1;
nkpt = NKPT;
#if BSDVM_COMPAT
/*
* Allocate all the submaps we need
*/
#define SYSMAP(c, p, v, n) \
v = (c)va; va += ((n)*NBPG); p = pte; pte += (n);
va = virtual_avail;
pte = pmap_pte(kernel_pmap, va);
SYSMAP(caddr_t, CMAP1, CADDR1, 1)
SYSMAP(caddr_t, CMAP2, CADDR2, 1)
SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
SYSMAP(struct msgbuf *, msgbufmap, msgbufp, 1)
virtual_avail = va;
#endif
/*
* Reserve special hunk of memory for use by bus dma as a bounce
* buffer (contiguous virtual *and* physical memory).
*/
{
isaphysmem = va;
virtual_avail = pmap_map(va, firstaddr,
firstaddr + DMAPAGES * NBPG, VM_PROT_ALL);
}
*(int *) CMAP1 = *(int *) CMAP2 = *(int *) PTD = 0;
pmap_update();
}
/*
* Initialize the pmap module.
* Called by vm_init, to initialize any structures that the pmap
* system needs to map virtual memory.
* pmap_init has been enhanced to support in a fairly consistant
* way, discontiguous physical memory.
*/
void
pmap_init(phys_start, phys_end)
vm_offset_t phys_start, phys_end;
{
vm_offset_t addr;
vm_size_t npg, s;
int i;
/*
* Now that kernel map has been allocated, we can mark as unavailable
* regions which we have mapped in locore.
*/
addr = atdevbase;
(void) vm_map_find(kernel_map, NULL, (vm_offset_t) 0,
&addr, (0x100000 - 0xa0000), FALSE);
addr = (vm_offset_t) KERNBASE + IdlePTD;
vm_object_reference(kernel_object);
(void) vm_map_find(kernel_map, kernel_object, addr,
&addr, (4 + NKPDE) * NBPG, FALSE);
/*
* calculate the number of pv_entries needed
*/
vm_first_phys = phys_avail[0];
for (i = 0; phys_avail[i + 1]; i += 2);
npg = (phys_avail[(i - 2) + 1] - vm_first_phys) / NBPG;
/*
* Allocate memory for random pmap data structures. Includes the
* pv_head_table.
*/
s = (vm_size_t) (sizeof(struct pv_entry) * npg);
s = i386_round_page(s);
addr = (vm_offset_t) kmem_alloc(kernel_map, s);
pv_table = (pv_entry_t) addr;
/*
* init the pv free list
*/
init_pv_entries(npg);
/*
* Now it is safe to enable pv_table recording.
*/
pmap_initialized = TRUE;
}
/*
* Used to map a range of physical addresses into kernel
* virtual address space.
*
* For now, VM is already on, we only need to map the
* specified memory.
*/
vm_offset_t
pmap_map(virt, start, end, prot)
vm_offset_t virt;
vm_offset_t start;
vm_offset_t end;
int prot;
{
while (start < end) {
pmap_enter(kernel_pmap, virt, start, prot, FALSE);
virt += PAGE_SIZE;
start += PAGE_SIZE;
}
return (virt);
}
/*
* Create and return a physical map.
*
* If the size specified for the map
* is zero, the map is an actual physical
* map, and may be referenced by the
* hardware.
*
* If the size specified is non-zero,
* the map will be used in software only, and
* is bounded by that size.
*
*/
pmap_t
pmap_create(size)
vm_size_t size;
{
register pmap_t pmap;
/*
* Software use map does not need a pmap
*/
if (size)
return (NULL);
pmap = (pmap_t) malloc(sizeof *pmap, M_VMPMAP, M_WAITOK);
bzero(pmap, sizeof(*pmap));
pmap_pinit(pmap);
return (pmap);
}
/*
* Initialize a preallocated and zeroed pmap structure,
* such as one in a vmspace structure.
*/
void
pmap_pinit(pmap)
register struct pmap *pmap;
{
/*
* No need to allocate page table space yet but we do need a valid
* page directory table.
*/
pmap->pm_pdir = (pd_entry_t *) kmem_alloc(kernel_map, PAGE_SIZE);
/* wire in kernel global address entries */
bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE);
/* install self-referential address mapping entry */
*(int *) (pmap->pm_pdir + PTDPTDI) =
((int) pmap_kextract((vm_offset_t) pmap->pm_pdir)) | PG_V | PG_KW;
pmap->pm_count = 1;
simple_lock_init(&pmap->pm_lock);
}
/*
* grow the number of kernel page table entries, if needed
*/
vm_page_t nkpg;
vm_offset_t kernel_vm_end;
void
pmap_growkernel(vm_offset_t addr)
{
struct proc *p;
struct pmap *pmap;
int s;
s = splhigh();
if (kernel_vm_end == 0) {
kernel_vm_end = KERNBASE;
nkpt = 0;
while (pdir_pde(PTD, kernel_vm_end)) {
kernel_vm_end = (kernel_vm_end + NBPG * NPTEPG) & ~(NBPG * NPTEPG - 1);
++nkpt;
}
}
addr = (addr + NBPG * NPTEPG) & ~(NBPG * NPTEPG - 1);
while (kernel_vm_end < addr) {
if (pdir_pde(PTD, kernel_vm_end)) {
kernel_vm_end = (kernel_vm_end + NBPG * NPTEPG) & ~(NBPG * NPTEPG - 1);
continue;
}
++nkpt;
if (!nkpg) {
nkpg = vm_page_alloc(kernel_object, 0, VM_ALLOC_SYSTEM);
if (!nkpg)
panic("pmap_growkernel: no memory to grow kernel");
vm_page_wire(nkpg);
vm_page_remove(nkpg);
pmap_zero_page(VM_PAGE_TO_PHYS(nkpg));
}
pdir_pde(PTD, kernel_vm_end) = (pd_entry_t) (VM_PAGE_TO_PHYS(nkpg) | PG_V | PG_KW);
nkpg = NULL;
for (p = (struct proc *) allproc; p != NULL; p = p->p_next) {
if (p->p_vmspace) {
pmap = &p->p_vmspace->vm_pmap;
*pmap_pde(pmap, kernel_vm_end) = pdir_pde(PTD, kernel_vm_end);
}
}
*pmap_pde(kernel_pmap, kernel_vm_end) = pdir_pde(PTD, kernel_vm_end);
kernel_vm_end = (kernel_vm_end + NBPG * NPTEPG) & ~(NBPG * NPTEPG - 1);
}
splx(s);
}
/*
* Retire the given physical map from service.
* Should only be called if the map contains
* no valid mappings.
*/
void
pmap_destroy(pmap)
register pmap_t pmap;
{
int count;
if (pmap == NULL)
return;
simple_lock(&pmap->pm_lock);
count = --pmap->pm_count;
simple_unlock(&pmap->pm_lock);
if (count == 0) {
pmap_release(pmap);
free((caddr_t) pmap, M_VMPMAP);
}
}
/*
* Release any resources held by the given physical map.
* Called when a pmap initialized by pmap_pinit is being released.
* Should only be called if the map contains no valid mappings.
*/
void
pmap_release(pmap)
register struct pmap *pmap;
{
kmem_free(kernel_map, (vm_offset_t) pmap->pm_pdir, PAGE_SIZE);
}
/*
* Add a reference to the specified pmap.
*/
void
pmap_reference(pmap)
pmap_t pmap;
{
if (pmap != NULL) {
simple_lock(&pmap->pm_lock);
pmap->pm_count++;
simple_unlock(&pmap->pm_lock);
}
}
#define PV_FREELIST_MIN ((NBPG / sizeof (struct pv_entry)) / 2)
/*
* Data for the pv entry allocation mechanism
*/
int pv_freelistcnt;
pv_entry_t pv_freelist;
vm_offset_t pvva;
int npvvapg;
/*
* free the pv_entry back to the free list
*/
inline static void
free_pv_entry(pv)
pv_entry_t pv;
{
if (!pv)
return;
++pv_freelistcnt;
pv->pv_next = pv_freelist;
pv_freelist = pv;
}
/*
* get a new pv_entry, allocating a block from the system
* when needed.
* the memory allocation is performed bypassing the malloc code
* because of the possibility of allocations at interrupt time.
*/
static inline pv_entry_t
get_pv_entry()
{
pv_entry_t tmp;
/*
* get more pv_entry pages if needed
*/
if (pv_freelistcnt < PV_FREELIST_MIN || pv_freelist == 0) {
pmap_alloc_pv_entry();
}
/*
* get a pv_entry off of the free list
*/
--pv_freelistcnt;
tmp = pv_freelist;
pv_freelist = tmp->pv_next;
return tmp;
}
/*
* this *strange* allocation routine *statistically* eliminates the
* *possibility* of a malloc failure (*FATAL*) for a pv_entry_t data structure.
* also -- this code is MUCH MUCH faster than the malloc equiv...
*/
static void
pmap_alloc_pv_entry()
{
/*
* do we have any pre-allocated map-pages left?
*/
if (npvvapg) {
vm_page_t m;
/*
* we do this to keep recursion away
*/
pv_freelistcnt += PV_FREELIST_MIN;
/*
* allocate a physical page out of the vm system
*/
m = vm_page_alloc(kernel_object,
pvva - vm_map_min(kernel_map), VM_ALLOC_INTERRUPT);
if (m) {
int newentries;
int i;
pv_entry_t entry;
newentries = (NBPG / sizeof(struct pv_entry));
/*
* wire the page
*/
vm_page_wire(m);
m->flags &= ~PG_BUSY;
/*
* let the kernel see it
*/
pmap_kenter(pvva, VM_PAGE_TO_PHYS(m));
entry = (pv_entry_t) pvva;
/*
* update the allocation pointers
*/
pvva += NBPG;
--npvvapg;
/*
* free the entries into the free list
*/
for (i = 0; i < newentries; i++) {
free_pv_entry(entry);
entry++;
}
}
pv_freelistcnt -= PV_FREELIST_MIN;
}
if (!pv_freelist)
panic("get_pv_entry: cannot get a pv_entry_t");
}
/*
* init the pv_entry allocation system
*/
#define PVSPERPAGE 64
void
init_pv_entries(npg)
int npg;
{
/*
* allocate enough kvm space for PVSPERPAGE entries per page (lots)
* kvm space is fairly cheap, be generous!!! (the system can panic if
* this is too small.)
*/
npvvapg = ((npg * PVSPERPAGE) * sizeof(struct pv_entry) + NBPG - 1) / NBPG;
pvva = kmem_alloc_pageable(kernel_map, npvvapg * NBPG);
/*
* get the first batch of entries
*/
free_pv_entry(get_pv_entry());
}
static pt_entry_t *
get_pt_entry(pmap)
pmap_t pmap;
{
vm_offset_t frame = (int) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
/* are we current address space or kernel? */
if (pmap == kernel_pmap || frame == ((int) PTDpde & PG_FRAME)) {
return PTmap;
}
/* otherwise, we are alternate address space */
if (frame != ((int) APTDpde & PG_FRAME)) {
APTDpde = pmap->pm_pdir[PTDPTDI];
pmap_update();
}
return APTmap;
}
/*
* If it is the first entry on the list, it is actually
* in the header and we must copy the following entry up
* to the header. Otherwise we must search the list for
* the entry. In either case we free the now unused entry.
*/
void
pmap_remove_entry(pmap, pv, va)
struct pmap *pmap;
pv_entry_t pv;
vm_offset_t va;
{
pv_entry_t npv;
int s;
s = splhigh();
if (pmap == pv->pv_pmap && va == pv->pv_va) {
npv = pv->pv_next;
if (npv) {
*pv = *npv;
free_pv_entry(npv);
} else {
pv->pv_pmap = NULL;
}
} else {
for (npv = pv->pv_next; npv; npv = npv->pv_next) {
if (pmap == npv->pv_pmap && va == npv->pv_va) {
break;
}
pv = npv;
}
if (npv) {
pv->pv_next = npv->pv_next;
free_pv_entry(npv);
}
}
splx(s);
}
/*
* Remove the given range of addresses from the specified map.
*
* It is assumed that the start and end are properly
* rounded to the page size.
*/
void
pmap_remove(pmap, sva, eva)
struct pmap *pmap;
register vm_offset_t sva;
register vm_offset_t eva;
{
register pt_entry_t *ptp, *ptq;
vm_offset_t pa;
register pv_entry_t pv;
vm_offset_t va;
vm_page_t m;
pt_entry_t oldpte;
if (pmap == NULL)
return;
ptp = get_pt_entry(pmap);
/*
* special handling of removing one page. a very
* common operation and easy to short circuit some
* code.
*/
if ((sva + NBPG) == eva) {
if (*pmap_pde(pmap, sva) == 0)
return;
ptq = ptp + i386_btop(sva);
if (!*ptq)
return;
/*
* Update statistics
*/
if (pmap_pte_w(ptq))
pmap->pm_stats.wired_count--;
pmap->pm_stats.resident_count--;
pa = pmap_pte_pa(ptq);
oldpte = *ptq;
*ptq = 0;
if (pmap_is_managed(pa)) {
if ((int) oldpte & PG_M) {
if ((sva < USRSTACK || sva >= KERNBASE) ||
(sva >= USRSTACK && sva < USRSTACK + (UPAGES * NBPG))) {
if (sva < clean_sva || sva >= clean_eva) {
PHYS_TO_VM_PAGE(pa)->dirty |= VM_PAGE_BITS_ALL;
}
}
}
pv = pa_to_pvh(pa);
pmap_remove_entry(pmap, pv, sva);
}
pmap_unuse_pt(pmap, sva);
pmap_update();
return;
}
sva = i386_btop(sva);
eva = i386_btop(eva);
while (sva < eva) {
/*
* Weed out invalid mappings. Note: we assume that the page
* directory table is always allocated, and in kernel virtual.
*/
if (*pmap_pde(pmap, i386_ptob(sva)) == 0) {
/* We can race ahead here, straight to next pde.. */
sva = ((sva + NPTEPG) & ~(NPTEPG - 1));
continue;
}
ptq = ptp + sva;
/*
* search for page table entries, use string operations that
* are much faster than explicitly scanning when page tables
* are not fully populated.
*/
if (*ptq == 0) {
vm_offset_t pdnxt = ((sva + NPTEPG) & ~(NPTEPG - 1));
vm_offset_t nscan = pdnxt - sva;
int found = 0;
if ((nscan + sva) > eva)
nscan = eva - sva;
asm("xorl %%eax,%%eax;cld;repe;scasl;jz 1f;incl %%eax;1:;" :
"=D"(ptq), "=a"(found) : "c"(nscan), "0"(ptq) : "cx");
if (!found) {
sva = pdnxt;
continue;
}
ptq -= 1;
sva = ptq - ptp;
}
/*
* Update statistics
*/
oldpte = *ptq;
if (((int) oldpte) & PG_W)
pmap->pm_stats.wired_count--;
pmap->pm_stats.resident_count--;
/*
* Invalidate the PTEs. XXX: should cluster them up and
* invalidate as many as possible at once.
*/
*ptq = 0;
va = i386_ptob(sva);
/*
* Remove from the PV table (raise IPL since we may be called
* at interrupt time).
*/
pa = ((int) oldpte) & PG_FRAME;
if (!pmap_is_managed(pa)) {
pmap_unuse_pt(pmap, va);
++sva;
continue;
}
if ((int) oldpte & PG_M) {
if ((va < USRSTACK || va >= KERNBASE) ||
(va >= USRSTACK && va < USRSTACK + (UPAGES * NBPG))) {
if (va < clean_sva || va >= clean_eva) {
PHYS_TO_VM_PAGE(pa)->dirty |= VM_PAGE_BITS_ALL;
}
}
}
pv = pa_to_pvh(pa);
pmap_remove_entry(pmap, pv, va);
pmap_unuse_pt(pmap, va);
++sva;
}
pmap_update();
}
/*
* Routine: pmap_remove_all
* Function:
* Removes this physical page from
* all physical maps in which it resides.
* Reflects back modify bits to the pager.
*
* Notes:
* Original versions of this routine were very
* inefficient because they iteratively called
* pmap_remove (slow...)
*/
void
pmap_remove_all(pa)
vm_offset_t pa;
{
register pv_entry_t pv, npv;
register pt_entry_t *pte, *ptp;
vm_offset_t va;
struct pmap *pmap;
vm_page_t m;
int s;
int anyvalid = 0;
/*
* Not one of ours
*/
/*
* XXX this makes pmap_page_protect(NONE) illegal for non-managed
* pages!
*/
if (!pmap_is_managed(pa))
return;
pa = i386_trunc_page(pa);
pv = pa_to_pvh(pa);
m = PHYS_TO_VM_PAGE(pa);
s = splhigh();
while (pv->pv_pmap != NULL) {
pmap = pv->pv_pmap;
ptp = get_pt_entry(pmap);
va = pv->pv_va;
pte = ptp + i386_btop(va);
if (pmap_pte_w(pte))
pmap->pm_stats.wired_count--;
if (*pte) {
pmap->pm_stats.resident_count--;
anyvalid++;
/*
* Update the vm_page_t clean and reference bits.
*/
if ((int) *pte & PG_M) {
if ((va < USRSTACK || va >= KERNBASE) ||
(va >= USRSTACK && va < USRSTACK + (UPAGES * NBPG))) {
if (va < clean_sva || va >= clean_eva) {
PHYS_TO_VM_PAGE(pa)->dirty |= VM_PAGE_BITS_ALL;
}
}
}
*pte = 0;
pmap_unuse_pt(pmap, va);
}
npv = pv->pv_next;
if (npv) {
*pv = *npv;
free_pv_entry(npv);
} else {
pv->pv_pmap = NULL;
}
}
splx(s);
if (anyvalid)
pmap_update();
}
/*
* Set the physical protection on the
* specified range of this map as requested.
*/
void
pmap_protect(pmap, sva, eva, prot)
register pmap_t pmap;
vm_offset_t sva, eva;
vm_prot_t prot;
{
register pt_entry_t *pte;
register vm_offset_t va;
int i386prot;
register pt_entry_t *ptp;
int evap = i386_btop(eva);
int anyvalid = 0;;
if (pmap == NULL)
return;
if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
pmap_remove(pmap, sva, eva);
return;
}
if (prot & VM_PROT_WRITE)
return;
ptp = get_pt_entry(pmap);
va = sva;
while (va < eva) {
int found = 0;
int svap;
vm_offset_t nscan;
/*
* Page table page is not allocated. Skip it, we don't want to
* force allocation of unnecessary PTE pages just to set the
* protection.
*/
if (!*pmap_pde(pmap, va)) {
/* XXX: avoid address wrap around */
nextpde:
if (va >= i386_trunc_pdr((vm_offset_t) - 1))
break;
va = i386_round_pdr(va + PAGE_SIZE);
continue;
}
pte = ptp + i386_btop(va);
if (*pte == 0) {
/*
* scan for a non-empty pte
*/
svap = pte - ptp;
nscan = ((svap + NPTEPG) & ~(NPTEPG - 1)) - svap;
if (nscan + svap > evap)
nscan = evap - svap;
found = 0;
if (nscan)
asm("xorl %%eax,%%eax;cld;repe;scasl;jz 1f;incl %%eax;1:;" :
"=D"(pte), "=a"(found) : "c"(nscan), "0"(pte) : "cx");
if (!found)
goto nextpde;
pte -= 1;
svap = pte - ptp;
va = i386_ptob(svap);
}
anyvalid++;
i386prot = pte_prot(pmap, prot);
if (va < UPT_MAX_ADDRESS) {
i386prot |= PG_u;
if (va >= UPT_MIN_ADDRESS)
i386prot |= PG_RW;
}
pmap_pte_set_prot(pte, i386prot);
va += PAGE_SIZE;
}
if (anyvalid)
pmap_update();
}
/*
* Insert the given physical page (p) at
* the specified virtual address (v) in the
* target physical map with the protection requested.
*
* If specified, the page will be wired down, meaning
* that the related pte can not be reclaimed.
*
* NB: This is the only routine which MAY NOT lazy-evaluate
* or lose information. That is, this routine must actually
* insert this page into the given map NOW.
*/
void
pmap_enter(pmap, va, pa, prot, wired)
register pmap_t pmap;
vm_offset_t va;
register vm_offset_t pa;
vm_prot_t prot;
boolean_t wired;
{
register pt_entry_t *pte;
register pt_entry_t npte;
vm_offset_t opa;
int ptevalid = 0;
if (pmap == NULL)
return;
va = i386_trunc_page(va);
pa = i386_trunc_page(pa);
if (va > VM_MAX_KERNEL_ADDRESS)
panic("pmap_enter: toobig");
/*
* Page Directory table entry not valid, we need a new PT page
*/
if (*pmap_pde(pmap, va) == 0) {
printf("kernel page directory invalid pdir=0x%x, va=0x%x\n", pmap->pm_pdir[PTDPTDI], va);
panic("invalid kernel page directory");
}
pte = pmap_pte(pmap, va);
opa = pmap_pte_pa(pte);
/*
* Mapping has not changed, must be protection or wiring change.
*/
if (opa == pa) {
/*
* Wiring change, just update stats. We don't worry about
* wiring PT pages as they remain resident as long as there
* are valid mappings in them. Hence, if a user page is wired,
* the PT page will be also.
*/
if (wired && !pmap_pte_w(pte))
pmap->pm_stats.wired_count++;
else if (!wired && pmap_pte_w(pte))
pmap->pm_stats.wired_count--;
goto validate;
}
/*
* Mapping has changed, invalidate old range and fall through to
* handle validating new mapping.
*/
if (opa) {
pmap_remove(pmap, va, va + PAGE_SIZE);
}
/*
* Enter on the PV list if part of our managed memory Note that we
* raise IPL while manipulating pv_table since pmap_enter can be
* called at interrupt time.
*/
if (pmap_is_managed(pa)) {
register pv_entry_t pv, npv;
int s;
pv = pa_to_pvh(pa);
s = splhigh();
/*
* No entries yet, use header as the first entry
*/
if (pv->pv_pmap == NULL) {
pv->pv_va = va;
pv->pv_pmap = pmap;
pv->pv_next = NULL;
}
/*
* There is at least one other VA mapping this page. Place
* this entry after the header.
*/
else {
npv = get_pv_entry();
npv->pv_va = va;
npv->pv_pmap = pmap;
npv->pv_next = pv->pv_next;
pv->pv_next = npv;
}
splx(s);
}
/*
* Increment counters
*/
pmap->pm_stats.resident_count++;
if (wired)
pmap->pm_stats.wired_count++;
validate:
/*
* Now validate mapping with desired protection/wiring.
*/
npte = (pt_entry_t) ((int) (pa | pte_prot(pmap, prot) | PG_V));
/*
* When forking (copy-on-write, etc): A process will turn off write
* permissions for any of its writable pages. If the data (object) is
* only referred to by one process, the processes map is modified
* directly as opposed to using the object manipulation routine. When
* using pmap_protect, the modified bits are not kept in the vm_page_t
* data structure. Therefore, when using pmap_enter in vm_fault to
* bring back writability of a page, there has been no memory of the
* modified or referenced bits except at the pte level. this clause
* supports the carryover of the modified and used (referenced) bits.
*/
if (pa == opa)
(int) npte |= (int) *pte & (PG_M | PG_U);
if (wired)
(int) npte |= PG_W;
if (va < UPT_MIN_ADDRESS)
(int) npte |= PG_u;
else if (va < UPT_MAX_ADDRESS)
(int) npte |= PG_u | PG_RW;
if (*pte != npte) {
if (*pte)
ptevalid++;
*pte = npte;
}
if (ptevalid) {
pmap_update();
} else {
pmap_use_pt(pmap, va);
}
}
/*
* Add a list of wired pages to the kva
* this routine is only used for temporary
* kernel mappings that do not need to have
* page modification or references recorded.
* Note that old mappings are simply written
* over. The page *must* be wired.
*/
void
pmap_qenter(va, m, count)
vm_offset_t va;
vm_page_t *m;
int count;
{
int i;
int anyvalid = 0;
register pt_entry_t *pte;
for (i = 0; i < count; i++) {
pte = vtopte(va + i * NBPG);
if (*pte)
anyvalid++;
*pte = (pt_entry_t) ((int) (VM_PAGE_TO_PHYS(m[i]) | PG_RW | PG_V | PG_W));
}
if (anyvalid)
pmap_update();
}
/*
* this routine jerks page mappings from the
* kernel -- it is meant only for temporary mappings.
*/
void
pmap_qremove(va, count)
vm_offset_t va;
int count;
{
int i;
register pt_entry_t *pte;
for (i = 0; i < count; i++) {
pte = vtopte(va + i * NBPG);
*pte = 0;
}
pmap_update();
}
/*
* add a wired page to the kva
* note that in order for the mapping to take effect -- you
* should do a pmap_update after doing the pmap_kenter...
*/
void
pmap_kenter(va, pa)
vm_offset_t va;
register vm_offset_t pa;
{
register pt_entry_t *pte;
int wasvalid = 0;
pte = vtopte(va);
if (*pte)
wasvalid++;
*pte = (pt_entry_t) ((int) (pa | PG_RW | PG_V | PG_W));
if (wasvalid)
pmap_update();
}
/*
* remove a page from the kernel pagetables
*/
void
pmap_kremove(va)
vm_offset_t va;
{
register pt_entry_t *pte;
pte = vtopte(va);
*pte = (pt_entry_t) 0;
pmap_update();
}
/*
* this code makes some *MAJOR* assumptions:
* 1. Current pmap & pmap exists.
* 2. Not wired.
* 3. Read access.
* 4. No page table pages.
* 5. Tlbflush is deferred to calling procedure.
* 6. Page IS managed.
* but is *MUCH* faster than pmap_enter...
*/
static inline void
pmap_enter_quick(pmap, va, pa)
register pmap_t pmap;
vm_offset_t va;
register vm_offset_t pa;
{
register pt_entry_t *pte;
register pv_entry_t pv, npv;
int s;
/*
* Enter on the PV list if part of our managed memory Note that we
* raise IPL while manipulating pv_table since pmap_enter can be
* called at interrupt time.
*/
pte = vtopte(va);
/* a fault on the page table might occur here */
if (*pte) {
pmap_remove(pmap, va, va + PAGE_SIZE);
}
pv = pa_to_pvh(pa);
s = splhigh();
/*
* No entries yet, use header as the first entry
*/
if (pv->pv_pmap == NULL) {
pv->pv_pmap = pmap;
pv->pv_va = va;
pv->pv_next = NULL;
}
/*
* There is at least one other VA mapping this page. Place this entry
* after the header.
*/
else {
npv = get_pv_entry();
npv->pv_va = va;
npv->pv_pmap = pmap;
npv->pv_next = pv->pv_next;
pv->pv_next = npv;
}
splx(s);
/*
* Increment counters
*/
pmap->pm_stats.resident_count++;
/*
* Now validate mapping with desired protection/wiring.
*/
*pte = (pt_entry_t) ((int) (pa | PG_V | PG_u));
pmap_use_pt(pmap, va);
return;
}
#define MAX_INIT_PT (1024*2048)
/*
* pmap_object_init_pt preloads the ptes for a given object
* into the specified pmap. This eliminates the blast of soft
* faults on process startup and immediately after an mmap.
*/
void
pmap_object_init_pt(pmap, addr, object, offset, size)
pmap_t pmap;
vm_offset_t addr;
vm_object_t object;
vm_offset_t offset;
vm_offset_t size;
{
vm_offset_t tmpoff;
vm_page_t p;
int bits;
int objbytes;
if (!pmap || ((size > MAX_INIT_PT) &&
(object->resident_page_count > (MAX_INIT_PT / NBPG)))) {
return;
}
if (!vm_object_lock_try(object))
return;
/*
* if we are processing a major portion of the object, then scan the
* entire thing.
*/
if (size > (object->size >> 2)) {
objbytes = size;
for (p = object->memq.tqh_first;
((objbytes > 0) && (p != NULL));
p = p->listq.tqe_next) {
tmpoff = p->offset;
if (tmpoff < offset) {
continue;
}
tmpoff -= offset;
if (tmpoff >= size) {
continue;
}
if (((p->flags & (PG_ACTIVE | PG_INACTIVE)) != 0) &&
((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(p->bmapped == 0) &&
(p->busy == 0) &&
(p->flags & (PG_BUSY | PG_FICTITIOUS | PG_CACHE)) == 0) {
vm_page_hold(p);
p->flags |= PG_MAPPED;
pmap_enter_quick(pmap, addr + tmpoff, VM_PAGE_TO_PHYS(p));
vm_page_unhold(p);
}
objbytes -= NBPG;
}
} else {
/*
* else lookup the pages one-by-one.
*/
for (tmpoff = 0; tmpoff < size; tmpoff += NBPG) {
p = vm_page_lookup(object, tmpoff + offset);
if (p && ((p->flags & (PG_ACTIVE | PG_INACTIVE)) != 0) &&
(p->bmapped == 0) && (p->busy == 0) &&
((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(p->flags & (PG_BUSY | PG_FICTITIOUS | PG_CACHE)) == 0) {
vm_page_hold(p);
p->flags |= PG_MAPPED;
pmap_enter_quick(pmap, addr + tmpoff, VM_PAGE_TO_PHYS(p));
vm_page_unhold(p);
}
}
}
vm_object_unlock(object);
}
#if 0
/*
* pmap_prefault provides a quick way of clustering
* pagefaults into a processes address space. It is a "cousin"
* of pmap_object_init_pt, except it runs at page fault time instead
* of mmap time.
*/
#define PFBAK 2
#define PFFOR 2
#define PAGEORDER_SIZE (PFBAK+PFFOR)
static int pmap_prefault_pageorder[] = {
-NBPG, NBPG, -2 * NBPG, 2 * NBPG
};
void
pmap_prefault(pmap, addra, entry, object)
pmap_t pmap;
vm_offset_t addra;
vm_map_entry_t entry;
vm_object_t object;
{
int i;
vm_offset_t starta, enda;
vm_offset_t offset, addr;
vm_page_t m;
int pageorder_index;
if (entry->object.vm_object != object)
return;
if (pmap != &curproc->p_vmspace->vm_pmap)
return;
starta = addra - PFBAK * NBPG;
if (starta < entry->start) {
starta = entry->start;
} else if (starta > addra)
starta = 0;
enda = addra + PFFOR * NBPG;
if (enda > entry->end)
enda = entry->end;
for (i = 0; i < PAGEORDER_SIZE; i++) {
vm_object_t lobject;
pt_entry_t *pte;
addr = addra + pmap_prefault_pageorder[i];
if (addr < starta || addr >= enda)
continue;
pte = vtopte(addr);
if (*pte)
continue;
offset = (addr - entry->start) + entry->offset;
lobject = object;
for (m = vm_page_lookup(lobject, offset);
(!m && lobject->shadow && !lobject->pager);
lobject = lobject->shadow) {
offset += lobject->shadow_offset;
m = vm_page_lookup(lobject->shadow, offset);
}
/*
* give-up when a page is not in memory
*/
if (m == NULL)
break;
if (((m->flags & (PG_CACHE | PG_ACTIVE | PG_INACTIVE)) != 0) &&
((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(m->busy == 0) &&
(m->bmapped == 0) &&
(m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
/*
* test results show that the system is faster when
* pages are activated.
*/
if ((m->flags & PG_ACTIVE) == 0) {
if( m->flags & PG_CACHE)
vm_page_deactivate(m);
else
vm_page_activate(m);
}
vm_page_hold(m);
m->flags |= PG_MAPPED;
pmap_enter_quick(pmap, addr, VM_PAGE_TO_PHYS(m));
vm_page_unhold(m);
}
}
}
#endif
/*
* Routine: pmap_change_wiring
* Function: Change the wiring attribute for a map/virtual-address
* pair.
* In/out conditions:
* The mapping must already exist in the pmap.
*/
void
pmap_change_wiring(pmap, va, wired)
register pmap_t pmap;
vm_offset_t va;
boolean_t wired;
{
register pt_entry_t *pte;
if (pmap == NULL)
return;
pte = pmap_pte(pmap, va);
if (wired && !pmap_pte_w(pte))
pmap->pm_stats.wired_count++;
else if (!wired && pmap_pte_w(pte))
pmap->pm_stats.wired_count--;
/*
* Wiring is not a hardware characteristic so there is no need to
* invalidate TLB.
*/
pmap_pte_set_w(pte, wired);
/*
* When unwiring, set the modified bit in the pte -- could have been
* changed by the kernel
*/
if (!wired)
(int) *pte |= PG_M;
}
/*
* Copy the range specified by src_addr/len
* from the source map to the range dst_addr/len
* in the destination map.
*
* This routine is only advisory and need not do anything.
*/
void
pmap_copy(dst_pmap, src_pmap, dst_addr, len, src_addr)
pmap_t dst_pmap, src_pmap;
vm_offset_t dst_addr;
vm_size_t len;
vm_offset_t src_addr;
{
}
/*
* Routine: pmap_kernel
* Function:
* Returns the physical map handle for the kernel.
*/
pmap_t
pmap_kernel()
{
return (kernel_pmap);
}
/*
* pmap_zero_page zeros the specified (machine independent)
* page by mapping the page into virtual memory and using
* bzero to clear its contents, one machine dependent page
* at a time.
*/
void
pmap_zero_page(phys)
vm_offset_t phys;
{
if (*(int *) CMAP2)
panic("pmap_zero_page: CMAP busy");
*(int *) CMAP2 = PG_V | PG_KW | i386_trunc_page(phys);
bzero(CADDR2, NBPG);
*(int *) CMAP2 = 0;
pmap_update();
}
/*
* pmap_copy_page copies the specified (machine independent)
* page by mapping the page into virtual memory and using
* bcopy to copy the page, one machine dependent page at a
* time.
*/
void
pmap_copy_page(src, dst)
vm_offset_t src;
vm_offset_t dst;
{
if (*(int *) CMAP1 || *(int *) CMAP2)
panic("pmap_copy_page: CMAP busy");
*(int *) CMAP1 = PG_V | PG_KW | i386_trunc_page(src);
*(int *) CMAP2 = PG_V | PG_KW | i386_trunc_page(dst);
#if __GNUC__ > 1
memcpy(CADDR2, CADDR1, NBPG);
#else
bcopy(CADDR1, CADDR2, NBPG);
#endif
*(int *) CMAP1 = 0;
*(int *) CMAP2 = 0;
pmap_update();
}
/*
* Routine: pmap_pageable
* Function:
* Make the specified pages (by pmap, offset)
* pageable (or not) as requested.
*
* A page which is not pageable may not take
* a fault; therefore, its page table entry
* must remain valid for the duration.
*
* This routine is merely advisory; pmap_enter
* will specify that these pages are to be wired
* down (or not) as appropriate.
*/
void
pmap_pageable(pmap, sva, eva, pageable)
pmap_t pmap;
vm_offset_t sva, eva;
boolean_t pageable;
{
}
/*
* this routine returns true if a physical page resides
* in the given pmap.
*/
boolean_t
pmap_page_exists(pmap, pa)
pmap_t pmap;
vm_offset_t pa;
{
register pv_entry_t pv;
int s;
if (!pmap_is_managed(pa))
return FALSE;
pv = pa_to_pvh(pa);
s = splhigh();
/*
* Not found, check current mappings returning immediately if found.
*/
if (pv->pv_pmap != NULL) {
for (; pv; pv = pv->pv_next) {
if (pv->pv_pmap == pmap) {
splx(s);
return TRUE;
}
}
}
splx(s);
return (FALSE);
}
/*
* pmap_testbit tests bits in pte's
* note that the testbit/changebit routines are inline,
* and a lot of things compile-time evaluate.
*/
static __inline boolean_t
pmap_testbit(pa, bit)
register vm_offset_t pa;
int bit;
{
register pv_entry_t pv;
pt_entry_t *pte;
int s;
if (!pmap_is_managed(pa))
return FALSE;
pv = pa_to_pvh(pa);
s = splhigh();
/*
* Not found, check current mappings returning immediately if found.
*/
if (pv->pv_pmap != NULL) {
for (; pv; pv = pv->pv_next) {
/*
* if the bit being tested is the modified bit, then
* mark UPAGES as always modified, and ptes as never
* modified.
*/
if (bit & PG_U) {
if ((pv->pv_va >= clean_sva) && (pv->pv_va < clean_eva)) {
continue;
}
}
if (bit & PG_M) {
if (pv->pv_va >= USRSTACK) {
if (pv->pv_va >= clean_sva && pv->pv_va < clean_eva) {
continue;
}
if (pv->pv_va < USRSTACK + (UPAGES * NBPG)) {
splx(s);
return TRUE;
} else if (pv->pv_va < KERNBASE) {
splx(s);
return FALSE;
}
}
}
if (!pv->pv_pmap) {
printf("Null pmap (tb) at va: 0x%lx\n", pv->pv_va);
continue;
}
pte = pmap_pte(pv->pv_pmap, pv->pv_va);
if ((int) *pte & bit) {
splx(s);
return TRUE;
}
}
}
splx(s);
return (FALSE);
}
/*
* this routine is used to modify bits in ptes
*/
static __inline void
pmap_changebit(pa, bit, setem)
vm_offset_t pa;
int bit;
boolean_t setem;
{
register pv_entry_t pv;
register pt_entry_t *pte, npte;
vm_offset_t va;
int s;
if (!pmap_is_managed(pa))
return;
pv = pa_to_pvh(pa);
s = splhigh();
/*
* Loop over all current mappings setting/clearing as appropos If
* setting RO do we need to clear the VAC?
*/
if (pv->pv_pmap != NULL) {
for (; pv; pv = pv->pv_next) {
va = pv->pv_va;
/*
* don't write protect pager mappings
*/
if (!setem && (bit == PG_RW)) {
if (va >= clean_sva && va < clean_eva)
continue;
}
if (!pv->pv_pmap) {
printf("Null pmap (cb) at va: 0x%lx\n", va);
continue;
}
pte = pmap_pte(pv->pv_pmap, va);
if (setem)
(int) npte = (int) *pte | bit;
else
(int) npte = (int) *pte & ~bit;
*pte = npte;
}
}
splx(s);
pmap_update();
}
/*
* pmap_page_protect:
*
* Lower the permission for all mappings to a given page.
*/
void
pmap_page_protect(phys, prot)
vm_offset_t phys;
vm_prot_t prot;
{
if ((prot & VM_PROT_WRITE) == 0) {
if (prot & (VM_PROT_READ | VM_PROT_EXECUTE))
pmap_changebit(phys, PG_RW, FALSE);
else
pmap_remove_all(phys);
}
}
vm_offset_t
pmap_phys_address(ppn)
int ppn;
{
return (i386_ptob(ppn));
}
/*
* pmap_is_referenced:
*
* Return whether or not the specified physical page was referenced
* by any physical maps.
*/
boolean_t
pmap_is_referenced(vm_offset_t pa)
{
return pmap_testbit((pa), PG_U);
}
/*
* pmap_is_modified:
*
* Return whether or not the specified physical page was modified
* in any physical maps.
*/
boolean_t
pmap_is_modified(vm_offset_t pa)
{
return pmap_testbit((pa), PG_M);
}
/*
* Clear the modify bits on the specified physical page.
*/
void
pmap_clear_modify(vm_offset_t pa)
{
pmap_changebit((pa), PG_M, FALSE);
}
/*
* pmap_clear_reference:
*
* Clear the reference bit on the specified physical page.
*/
void
pmap_clear_reference(vm_offset_t pa)
{
pmap_changebit((pa), PG_U, FALSE);
}
/*
* Routine: pmap_copy_on_write
* Function:
* Remove write privileges from all
* physical maps for this physical page.
*/
void
pmap_copy_on_write(vm_offset_t pa)
{
pmap_changebit((pa), PG_RW, FALSE);
}
/*
* Miscellaneous support routines follow
*/
void
i386_protection_init()
{
register int *kp, prot;
kp = protection_codes;
for (prot = 0; prot < 8; prot++) {
switch (prot) {
case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_NONE:
/*
* Read access is also 0. There isn't any execute bit,
* so just make it readable.
*/
case VM_PROT_READ | VM_PROT_NONE | VM_PROT_NONE:
case VM_PROT_READ | VM_PROT_NONE | VM_PROT_EXECUTE:
case VM_PROT_NONE | VM_PROT_NONE | VM_PROT_EXECUTE:
*kp++ = 0;
break;
case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_NONE:
case VM_PROT_NONE | VM_PROT_WRITE | VM_PROT_EXECUTE:
case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_NONE:
case VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE:
*kp++ = PG_RW;
break;
}
}
}
/*
* Map a set of physical memory pages into the kernel virtual
* address space. Return a pointer to where it is mapped. This
* routine is intended to be used for mapping device memory,
* NOT real memory. The non-cacheable bits are set on each
* mapped page.
*/
void *
pmap_mapdev(pa, size)
vm_offset_t pa;
vm_size_t size;
{
vm_offset_t va, tmpva;
pt_entry_t *pte;
pa = trunc_page(pa);
size = roundup(size, PAGE_SIZE);
va = kmem_alloc_pageable(kernel_map, size);
if (!va)
panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
for (tmpva = va; size > 0;) {
pte = vtopte(tmpva);
*pte = (pt_entry_t) ((int) (pa | PG_RW | PG_V | PG_N));
size -= PAGE_SIZE;
tmpva += PAGE_SIZE;
pa += PAGE_SIZE;
}
pmap_update();
return ((void *) va);
}
#ifdef DEBUG
/* print address space of pmap*/
void
pads(pm)
pmap_t pm;
{
unsigned va, i, j;
pt_entry_t *ptep;
if (pm == kernel_pmap)
return;
for (i = 0; i < 1024; i++)
if (pm->pm_pdir[i])
for (j = 0; j < 1024; j++) {
va = (i << PD_SHIFT) + (j << PG_SHIFT);
if (pm == kernel_pmap && va < KERNBASE)
continue;
if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
continue;
ptep = pmap_pte(pm, va);
if (pmap_pte_v(ptep))
printf("%x:%x ", va, *(int *) ptep);
};
}
void
pmap_pvdump(pa)
vm_offset_t pa;
{
register pv_entry_t pv;
printf("pa %x", pa);
for (pv = pa_to_pvh(pa); pv; pv = pv->pv_next) {
#ifdef used_to_be
printf(" -> pmap %x, va %x, flags %x",
pv->pv_pmap, pv->pv_va, pv->pv_flags);
#endif
printf(" -> pmap %x, va %x",
pv->pv_pmap, pv->pv_va);
pads(pv->pv_pmap);
}
printf(" ");
}
#endif
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