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freebsd-dev/sys/i386/i386/pmap.c

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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
* $FreeBSD$
*/
/*
* 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 "opt_disable_pse.h"
#include "opt_pmap.h"
#include "opt_msgbuf.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/lock.h>
#include <sys/mman.h>
#include <sys/msgbuf.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/sx.h>
#include <sys/user.h>
#include <sys/vmmeter.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_extern.h>
#include <vm/vm_pageout.h>
#include <vm/vm_pager.h>
#include <vm/vm_zone.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>
#if defined(SMP) || defined(APIC_IO)
#include <machine/smp.h>
#include <machine/apic.h>
#include <machine/segments.h>
#include <machine/tss.h>
#include <machine/globaldata.h>
#endif /* SMP || APIC_IO */
#define PMAP_KEEP_PDIRS
#ifndef PMAP_SHPGPERPROC
#define PMAP_SHPGPERPROC 200
#endif
#if defined(DIAGNOSTIC)
#define PMAP_DIAGNOSTIC
#endif
#define MINPV 2048
#if !defined(PMAP_DIAGNOSTIC)
#define PMAP_INLINE __inline
#else
#define PMAP_INLINE
#endif
/*
* Get PDEs and PTEs for user/kernel address space
*/
#define pmap_pde(m, v) (&((m)->pm_pdir[(vm_offset_t)(v) >> PDRSHIFT]))
#define pdir_pde(m, v) (m[(vm_offset_t)(v) >> PDRSHIFT])
#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_A) != 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])
static int protection_codes[8];
static struct pmap kernel_pmap_store;
pmap_t kernel_pmap;
LIST_HEAD(pmaplist, pmap);
struct pmaplist allpmaps;
vm_offset_t avail_start; /* PA of first available physical page */
vm_offset_t avail_end; /* PA of last available physical page */
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) */
static boolean_t pmap_initialized = FALSE; /* Has pmap_init completed? */
static int pgeflag; /* PG_G or-in */
static int pseflag; /* PG_PS or-in */
static vm_object_t kptobj;
static int nkpt;
vm_offset_t kernel_vm_end;
/*
* Data for the pv entry allocation mechanism
*/
static vm_zone_t pvzone;
static struct vm_zone pvzone_store;
static struct vm_object pvzone_obj;
static int pv_entry_count=0, pv_entry_max=0, pv_entry_high_water=0;
static int pmap_pagedaemon_waken = 0;
static struct pv_entry *pvinit;
/*
* All those kernel PT submaps that BSD is so fond of
*/
pt_entry_t *CMAP1 = 0;
static pt_entry_t *CMAP2, *ptmmap;
caddr_t CADDR1 = 0, ptvmmap = 0;
static caddr_t CADDR2;
static pt_entry_t *msgbufmap;
struct msgbuf *msgbufp=0;
/*
* Crashdump maps.
*/
static pt_entry_t *pt_crashdumpmap;
static caddr_t crashdumpmap;
#ifdef SMP
extern pt_entry_t *SMPpt;
#endif
static pt_entry_t *PMAP1 = 0;
static unsigned *PADDR1 = 0;
static PMAP_INLINE void free_pv_entry __P((pv_entry_t pv));
static unsigned * get_ptbase __P((pmap_t pmap));
static pv_entry_t get_pv_entry __P((void));
static void i386_protection_init __P((void));
static __inline void pmap_changebit __P((vm_page_t m, int bit, boolean_t setem));
static void pmap_remove_all __P((vm_page_t m));
static vm_page_t pmap_enter_quick __P((pmap_t pmap, vm_offset_t va,
vm_page_t m, vm_page_t mpte));
static int pmap_remove_pte __P((struct pmap *pmap, unsigned *ptq,
vm_offset_t sva));
static void pmap_remove_page __P((struct pmap *pmap, vm_offset_t va));
static int pmap_remove_entry __P((struct pmap *pmap, vm_page_t m,
vm_offset_t va));
static boolean_t pmap_testbit __P((vm_page_t m, int bit));
static void pmap_insert_entry __P((pmap_t pmap, vm_offset_t va,
vm_page_t mpte, vm_page_t m));
static vm_page_t pmap_allocpte __P((pmap_t pmap, vm_offset_t va));
static int pmap_release_free_page __P((pmap_t pmap, vm_page_t p));
static vm_page_t _pmap_allocpte __P((pmap_t pmap, unsigned ptepindex));
static unsigned * pmap_pte_quick __P((pmap_t pmap, vm_offset_t va));
static vm_page_t pmap_page_lookup __P((vm_object_t object, vm_pindex_t pindex));
static int pmap_unuse_pt __P((pmap_t, vm_offset_t, vm_page_t));
static vm_offset_t pmap_kmem_choose(vm_offset_t addr);
static unsigned pdir4mb;
/*
* Routine: pmap_pte
* Function:
* Extract the page table entry associated
* with the given map/virtual_address pair.
*/
PMAP_INLINE unsigned *
pmap_pte(pmap, va)
register pmap_t pmap;
vm_offset_t va;
{
unsigned *pdeaddr;
if (pmap) {
pdeaddr = (unsigned *) pmap_pde(pmap, va);
if (*pdeaddr & PG_PS)
return pdeaddr;
if (*pdeaddr) {
return get_ptbase(pmap) + i386_btop(va);
}
}
return (0);
}
/*
* Move the kernel virtual free pointer to the next
* 4MB. This is used to help improve performance
* by using a large (4MB) page for much of the kernel
* (.text, .data, .bss)
*/
static vm_offset_t
pmap_kmem_choose(vm_offset_t addr)
{
vm_offset_t newaddr = addr;
#ifndef DISABLE_PSE
if (cpu_feature & CPUID_PSE) {
newaddr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
}
#endif
return newaddr;
}
/*
* Bootstrap the system enough to run with virtual memory.
*
* 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]
*/
void
pmap_bootstrap(firstaddr, loadaddr)
vm_offset_t firstaddr;
vm_offset_t loadaddr;
{
vm_offset_t va;
pt_entry_t *pte;
int i;
avail_start = firstaddr;
/*
* XXX The calculation of virtual_avail is wrong. It's NKPT*PAGE_SIZE too
* large. It should instead be correctly calculated in locore.s and
* not based on 'first' (which is a physical address, not a virtual
* address, for the start of unused physical memory). The kernel
* page tables are NOT double mapped and thus should not be included
* in this calculation.
*/
virtual_avail = (vm_offset_t) KERNBASE + firstaddr;
virtual_avail = pmap_kmem_choose(virtual_avail);
virtual_end = VM_MAX_KERNEL_ADDRESS;
/*
* 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 (XXX and which no longer exists).
*/
kernel_pmap = &kernel_pmap_store;
kernel_pmap->pm_pdir = (pd_entry_t *) (KERNBASE + (u_int)IdlePTD);
kernel_pmap->pm_count = 1;
kernel_pmap->pm_active = -1; /* don't allow deactivation */
TAILQ_INIT(&kernel_pmap->pm_pvlist);
LIST_INIT(&allpmaps);
LIST_INSERT_HEAD(&allpmaps, kernel_pmap, pm_list);
nkpt = NKPT;
/*
* Reserve some special page table entries/VA space for temporary
* mapping of pages.
*/
#define SYSMAP(c, p, v, n) \
v = (c)va; va += ((n)*PAGE_SIZE); p = pte; pte += (n);
va = virtual_avail;
pte = (pt_entry_t *) pmap_pte(kernel_pmap, va);
/*
* CMAP1/CMAP2 are used for zeroing and copying pages.
*/
SYSMAP(caddr_t, CMAP1, CADDR1, 1)
SYSMAP(caddr_t, CMAP2, CADDR2, 1)
/*
* Crashdump maps.
*/
SYSMAP(caddr_t, pt_crashdumpmap, crashdumpmap, MAXDUMPPGS);
/*
* ptvmmap is used for reading arbitrary physical pages via /dev/mem.
* XXX ptmmap is not used.
*/
SYSMAP(caddr_t, ptmmap, ptvmmap, 1)
/*
* msgbufp is used to map the system message buffer.
* XXX msgbufmap is not used.
*/
SYSMAP(struct msgbuf *, msgbufmap, msgbufp,
atop(round_page(MSGBUF_SIZE)))
/*
* ptemap is used for pmap_pte_quick
*/
SYSMAP(unsigned *, PMAP1, PADDR1, 1);
virtual_avail = va;
*(int *) CMAP1 = *(int *) CMAP2 = 0;
for (i = 0; i < NKPT; i++)
PTD[i] = 0;
pgeflag = 0;
#if !defined(SMP) /* XXX - see also mp_machdep.c */
if (cpu_feature & CPUID_PGE) {
pgeflag = PG_G;
}
#endif
/*
* Initialize the 4MB page size flag
*/
pseflag = 0;
/*
* The 4MB page version of the initial
* kernel page mapping.
*/
pdir4mb = 0;
#if !defined(DISABLE_PSE)
if (cpu_feature & CPUID_PSE) {
unsigned ptditmp;
/*
* Note that we have enabled PSE mode
*/
pseflag = PG_PS;
ptditmp = *((unsigned *)PTmap + i386_btop(KERNBASE));
ptditmp &= ~(NBPDR - 1);
ptditmp |= PG_V | PG_RW | PG_PS | PG_U | pgeflag;
pdir4mb = ptditmp;
#if !defined(SMP)
/*
* Enable the PSE mode.
*/
load_cr4(rcr4() | CR4_PSE);
/*
* We can do the mapping here for the single processor
* case. We simply ignore the old page table page from
* now on.
*/
/*
* For SMP, we still need 4K pages to bootstrap APs,
* PSE will be enabled as soon as all APs are up.
*/
PTD[KPTDI] = (pd_entry_t) ptditmp;
kernel_pmap->pm_pdir[KPTDI] = (pd_entry_t) ptditmp;
invltlb();
#endif
}
#endif
#ifdef SMP
if (cpu_apic_address == 0)
panic("pmap_bootstrap: no local apic! (non-SMP hardware?)");
/* local apic is mapped on last page */
SMPpt[NPTEPG - 1] = (pt_entry_t)(PG_V | PG_RW | PG_N | pgeflag |
(cpu_apic_address & PG_FRAME));
#endif
invltlb();
}
#ifdef SMP
/*
* Set 4mb pdir for mp startup
*/
void
pmap_set_opt(void)
{
if (pseflag && (cpu_feature & CPUID_PSE)) {
load_cr4(rcr4() | CR4_PSE);
if (pdir4mb && PCPU_GET(cpuid) == 0) { /* only on BSP */
kernel_pmap->pm_pdir[KPTDI] =
PTD[KPTDI] = (pd_entry_t)pdir4mb;
cpu_invltlb();
}
}
}
#endif
/*
* 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;
{
int i;
int initial_pvs;
/*
* object for kernel page table pages
*/
kptobj = vm_object_allocate(OBJT_DEFAULT, NKPDE);
/*
* Allocate memory for random pmap data structures. Includes the
* pv_head_table.
*/
for(i = 0; i < vm_page_array_size; i++) {
vm_page_t m;
m = &vm_page_array[i];
TAILQ_INIT(&m->md.pv_list);
m->md.pv_list_count = 0;
}
/*
* init the pv free list
*/
initial_pvs = vm_page_array_size;
if (initial_pvs < MINPV)
initial_pvs = MINPV;
pvzone = &pvzone_store;
pvinit = (struct pv_entry *) kmem_alloc(kernel_map,
initial_pvs * sizeof (struct pv_entry));
zbootinit(pvzone, "PV ENTRY", sizeof (struct pv_entry), pvinit,
vm_page_array_size);
/*
* Now it is safe to enable pv_table recording.
*/
pmap_initialized = TRUE;
}
/*
* Initialize the address space (zone) for the pv_entries. Set a
* high water mark so that the system can recover from excessive
* numbers of pv entries.
*/
void
pmap_init2()
{
pv_entry_max = PMAP_SHPGPERPROC * maxproc + vm_page_array_size;
pv_entry_high_water = 9 * (pv_entry_max / 10);
zinitna(pvzone, &pvzone_obj, NULL, 0, pv_entry_max, ZONE_INTERRUPT, 1);
}
/***************************************************
* Low level helper routines.....
***************************************************/
#if defined(PMAP_DIAGNOSTIC)
/*
* This code checks for non-writeable/modified pages.
* This should be an invalid condition.
*/
static int
pmap_nw_modified(pt_entry_t ptea)
{
int pte;
pte = (int) ptea;
if ((pte & (PG_M|PG_RW)) == PG_M)
return 1;
else
return 0;
}
#endif
/*
* this routine defines the region(s) of memory that should
* not be tested for the modified bit.
*/
static PMAP_INLINE int
pmap_track_modified(vm_offset_t va)
{
if ((va < clean_sva) || (va >= clean_eva))
return 1;
else
return 0;
}
static PMAP_INLINE void
invltlb_1pg(vm_offset_t va)
{
#ifdef I386_CPU
invltlb();
#else
invlpg(va);
#endif
}
static __inline void
pmap_TLB_invalidate(pmap_t pmap, vm_offset_t va)
{
#if defined(SMP)
if (pmap->pm_active & (1 << PCPU_GET(cpuid)))
cpu_invlpg((void *)va);
if (pmap->pm_active & PCPU_GET(other_cpus))
smp_invltlb();
#else
if (pmap->pm_active)
invltlb_1pg(va);
#endif
}
static __inline void
pmap_TLB_invalidate_all(pmap_t pmap)
{
#if defined(SMP)
if (pmap->pm_active & (1 << PCPU_GET(cpuid)))
cpu_invltlb();
if (pmap->pm_active & PCPU_GET(other_cpus))
smp_invltlb();
#else
if (pmap->pm_active)
invltlb();
#endif
}
static unsigned *
get_ptbase(pmap)
pmap_t pmap;
{
unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
/* are we current address space or kernel? */
if (pmap == kernel_pmap || frame == (((unsigned) PTDpde) & PG_FRAME)) {
return (unsigned *) PTmap;
}
/* otherwise, we are alternate address space */
if (frame != (((unsigned) APTDpde) & PG_FRAME)) {
APTDpde = (pd_entry_t) (frame | PG_RW | PG_V);
#if defined(SMP)
/* The page directory is not shared between CPUs */
cpu_invltlb();
#else
invltlb();
#endif
}
return (unsigned *) APTmap;
}
/*
* Super fast pmap_pte routine best used when scanning
* the pv lists. This eliminates many coarse-grained
* invltlb calls. Note that many of the pv list
* scans are across different pmaps. It is very wasteful
* to do an entire invltlb for checking a single mapping.
*/
static unsigned *
pmap_pte_quick(pmap, va)
register pmap_t pmap;
vm_offset_t va;
{
unsigned pde, newpf;
if ((pde = (unsigned) pmap->pm_pdir[va >> PDRSHIFT]) != 0) {
unsigned frame = (unsigned) pmap->pm_pdir[PTDPTDI] & PG_FRAME;
unsigned index = i386_btop(va);
/* are we current address space or kernel? */
if ((pmap == kernel_pmap) ||
(frame == (((unsigned) PTDpde) & PG_FRAME))) {
return (unsigned *) PTmap + index;
}
newpf = pde & PG_FRAME;
if ( ((* (unsigned *) PMAP1) & PG_FRAME) != newpf) {
* (unsigned *) PMAP1 = newpf | PG_RW | PG_V;
invltlb_1pg((vm_offset_t) PADDR1);
}
return PADDR1 + ((unsigned) index & (NPTEPG - 1));
}
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 rtval;
vm_offset_t pdirindex;
pdirindex = va >> PDRSHIFT;
if (pmap && (rtval = (unsigned) pmap->pm_pdir[pdirindex])) {
unsigned *pte;
if ((rtval & PG_PS) != 0) {
rtval &= ~(NBPDR - 1);
rtval |= va & (NBPDR - 1);
return rtval;
}
pte = get_ptbase(pmap) + i386_btop(va);
rtval = ((*pte & PG_FRAME) | (va & PAGE_MASK));
return rtval;
}
return 0;
}
/***************************************************
* Low level mapping routines.....
***************************************************/
/*
* add a wired page to the kva
* note that in order for the mapping to take effect -- you
* should do a invltlb after doing the pmap_kenter...
*/
PMAP_INLINE void
pmap_kenter(va, pa)
vm_offset_t va;
register vm_offset_t pa;
{
register unsigned *pte;
unsigned npte, opte;
npte = pa | PG_RW | PG_V | pgeflag;
pte = (unsigned *)vtopte(va);
opte = *pte;
*pte = npte;
/*if (opte)*/
invltlb_1pg(va); /* XXX what about SMP? */
}
/*
* remove a page from the kernel pagetables
*/
PMAP_INLINE void
pmap_kremove(va)
vm_offset_t va;
{
register unsigned *pte;
pte = (unsigned *)vtopte(va);
*pte = 0;
invltlb_1pg(va); /* XXX what about SMP? */
}
/*
* Used to map a range of physical addresses into kernel
* virtual address space.
*
* The value passed in '*virt' is a suggested virtual address for
* the mapping. Architectures which can support a direct-mapped
* physical to virtual region can return the appropriate address
* within that region, leaving '*virt' unchanged. Other
* architectures should map the pages starting at '*virt' and
* update '*virt' with the first usable address after the mapped
* region.
*/
vm_offset_t
pmap_map(virt, start, end, prot)
vm_offset_t *virt;
vm_offset_t start;
vm_offset_t end;
int prot;
{
vm_offset_t sva = *virt;
vm_offset_t va = sva;
while (start < end) {
pmap_kenter(va, start);
va += PAGE_SIZE;
start += PAGE_SIZE;
}
*virt = va;
return (sva);
}
/*
* 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;
for (i = 0; i < count; i++) {
vm_offset_t tva = va + i * PAGE_SIZE;
pmap_kenter(tva, VM_PAGE_TO_PHYS(m[i]));
}
}
/*
* 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;
{
vm_offset_t end_va;
end_va = va + count*PAGE_SIZE;
while (va < end_va) {
unsigned *pte;
pte = (unsigned *)vtopte(va);
*pte = 0;
#ifdef SMP
cpu_invlpg((void *)va);
#else
invltlb_1pg(va);
#endif
va += PAGE_SIZE;
}
#ifdef SMP
smp_invltlb();
#endif
}
static vm_page_t
pmap_page_lookup(object, pindex)
vm_object_t object;
vm_pindex_t pindex;
{
vm_page_t m;
retry:
m = vm_page_lookup(object, pindex);
if (m && vm_page_sleep_busy(m, FALSE, "pplookp"))
goto retry;
return m;
}
/*
* Create the UPAGES for a new process.
* This routine directly affects the fork perf for a process.
*/
void
pmap_new_proc(p)
struct proc *p;
{
#ifdef I386_CPU
int updateneeded;
#endif
int i;
vm_object_t upobj;
vm_page_t m;
struct user *up;
unsigned *ptek, oldpte;
/*
* allocate object for the upages
*/
if ((upobj = p->p_upages_obj) == NULL) {
upobj = vm_object_allocate( OBJT_DEFAULT, UPAGES);
p->p_upages_obj = upobj;
}
/* get a kernel virtual address for the UPAGES for this proc */
if ((up = p->p_addr) == NULL) {
up = (struct user *) kmem_alloc_nofault(kernel_map,
UPAGES * PAGE_SIZE);
if (up == NULL)
panic("pmap_new_proc: u_map allocation failed");
p->p_addr = up;
}
ptek = (unsigned *) vtopte((vm_offset_t) up);
#ifdef I386_CPU
updateneeded = 0;
#endif
for(i=0;i<UPAGES;i++) {
/*
* Get a kernel stack page
*/
m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
/*
* Wire the page
*/
m->wire_count++;
cnt.v_wire_count++;
oldpte = *(ptek + i);
/*
* Enter the page into the kernel address space.
*/
*(ptek + i) = VM_PAGE_TO_PHYS(m) | PG_RW | PG_V | pgeflag;
if (oldpte) {
#ifdef I386_CPU
updateneeded = 1;
#else
invlpg((vm_offset_t) up + i * PAGE_SIZE);
#endif
}
vm_page_wakeup(m);
vm_page_flag_clear(m, PG_ZERO);
vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
m->valid = VM_PAGE_BITS_ALL;
}
#ifdef I386_CPU
if (updateneeded)
invltlb();
#endif
}
/*
* Dispose the UPAGES for a process that has exited.
* This routine directly impacts the exit perf of a process.
*/
void
pmap_dispose_proc(p)
struct proc *p;
{
int i;
vm_object_t upobj;
vm_page_t m;
unsigned *ptek, oldpte;
upobj = p->p_upages_obj;
ptek = (unsigned *) vtopte((vm_offset_t) p->p_addr);
for(i=0;i<UPAGES;i++) {
if ((m = vm_page_lookup(upobj, i)) == NULL)
panic("pmap_dispose_proc: upage already missing???");
vm_page_busy(m);
oldpte = *(ptek + i);
*(ptek + i) = 0;
#ifndef I386_CPU
invlpg((vm_offset_t) p->p_addr + i * PAGE_SIZE);
#endif
vm_page_unwire(m, 0);
vm_page_free(m);
}
#ifdef I386_CPU
invltlb();
#endif
}
/*
* Allow the UPAGES for a process to be prejudicially paged out.
*/
void
pmap_swapout_proc(p)
struct proc *p;
{
int i;
vm_object_t upobj;
vm_page_t m;
upobj = p->p_upages_obj;
/*
* let the upages be paged
*/
for(i=0;i<UPAGES;i++) {
if ((m = vm_page_lookup(upobj, i)) == NULL)
panic("pmap_swapout_proc: upage already missing???");
vm_page_dirty(m);
vm_page_unwire(m, 0);
pmap_kremove( (vm_offset_t) p->p_addr + PAGE_SIZE * i);
}
}
/*
* Bring the UPAGES for a specified process back in.
*/
void
pmap_swapin_proc(p)
struct proc *p;
{
int i,rv;
vm_object_t upobj;
vm_page_t m;
upobj = p->p_upages_obj;
for(i=0;i<UPAGES;i++) {
m = vm_page_grab(upobj, i, VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
pmap_kenter(((vm_offset_t) p->p_addr) + i * PAGE_SIZE,
VM_PAGE_TO_PHYS(m));
if (m->valid != VM_PAGE_BITS_ALL) {
rv = vm_pager_get_pages(upobj, &m, 1, 0);
if (rv != VM_PAGER_OK)
panic("pmap_swapin_proc: cannot get upages for proc: %d\n", p->p_pid);
m = vm_page_lookup(upobj, i);
m->valid = VM_PAGE_BITS_ALL;
}
vm_page_wire(m);
vm_page_wakeup(m);
vm_page_flag_set(m, PG_MAPPED | PG_WRITEABLE);
}
}
/***************************************************
* Page table page management routines.....
***************************************************/
/*
* This routine unholds page table pages, and if the hold count
* drops to zero, then it decrements the wire count.
*/
static int
_pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m) {
while (vm_page_sleep_busy(m, FALSE, "pmuwpt"))
;
if (m->hold_count == 0) {
vm_offset_t pteva;
/*
* unmap the page table page
*/
pmap->pm_pdir[m->pindex] = 0;
--pmap->pm_stats.resident_count;
if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
(((unsigned) PTDpde) & PG_FRAME)) {
/*
* Do a invltlb to make the invalidated mapping
* take effect immediately.
*/
pteva = UPT_MIN_ADDRESS + i386_ptob(m->pindex);
pmap_TLB_invalidate(pmap, pteva);
}
if (pmap->pm_ptphint == m)
pmap->pm_ptphint = NULL;
/*
* If the page is finally unwired, simply free it.
*/
--m->wire_count;
if (m->wire_count == 0) {
vm_page_flash(m);
vm_page_busy(m);
vm_page_free_zero(m);
--cnt.v_wire_count;
}
return 1;
}
return 0;
}
static PMAP_INLINE int
pmap_unwire_pte_hold(pmap_t pmap, vm_page_t m)
{
vm_page_unhold(m);
if (m->hold_count == 0)
return _pmap_unwire_pte_hold(pmap, m);
else
return 0;
}
/*
* After removing a page table entry, this routine is used to
* conditionally free the page, and manage the hold/wire counts.
*/
static int
pmap_unuse_pt(pmap, va, mpte)
pmap_t pmap;
vm_offset_t va;
vm_page_t mpte;
{
unsigned ptepindex;
if (va >= UPT_MIN_ADDRESS)
return 0;
if (mpte == NULL) {
ptepindex = (va >> PDRSHIFT);
if (pmap->pm_ptphint &&
(pmap->pm_ptphint->pindex == ptepindex)) {
mpte = pmap->pm_ptphint;
} else {
mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
pmap->pm_ptphint = mpte;
}
}
return pmap_unwire_pte_hold(pmap, mpte);
}
void
pmap_pinit0(pmap)
struct pmap *pmap;
{
pmap->pm_pdir =
(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
pmap_kenter((vm_offset_t) pmap->pm_pdir, (vm_offset_t) IdlePTD);
pmap->pm_count = 1;
pmap->pm_active = 0;
pmap->pm_ptphint = NULL;
TAILQ_INIT(&pmap->pm_pvlist);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
}
/*
* Initialize a preallocated and zeroed pmap structure,
* such as one in a vmspace structure.
*/
void
pmap_pinit(pmap)
register struct pmap *pmap;
{
vm_page_t ptdpg;
/*
* No need to allocate page table space yet but we do need a valid
* page directory table.
*/
if (pmap->pm_pdir == NULL)
pmap->pm_pdir =
(pd_entry_t *)kmem_alloc_pageable(kernel_map, PAGE_SIZE);
/*
* allocate object for the ptes
*/
if (pmap->pm_pteobj == NULL)
pmap->pm_pteobj = vm_object_allocate( OBJT_DEFAULT, PTDPTDI + 1);
/*
* allocate the page directory page
*/
ptdpg = vm_page_grab( pmap->pm_pteobj, PTDPTDI,
VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
ptdpg->wire_count = 1;
++cnt.v_wire_count;
vm_page_flag_clear(ptdpg, PG_MAPPED | PG_BUSY); /* not usually mapped*/
ptdpg->valid = VM_PAGE_BITS_ALL;
pmap_kenter((vm_offset_t) pmap->pm_pdir, VM_PAGE_TO_PHYS(ptdpg));
if ((ptdpg->flags & PG_ZERO) == 0)
bzero(pmap->pm_pdir, PAGE_SIZE);
LIST_INSERT_HEAD(&allpmaps, pmap, pm_list);
/* Wire in kernel global address entries. */
/* XXX copies current process, does not fill in MPPTDI */
bcopy(PTD + KPTDI, pmap->pm_pdir + KPTDI, nkpt * PTESIZE);
#ifdef SMP
pmap->pm_pdir[MPPTDI] = PTD[MPPTDI];
#endif
/* install self-referential address mapping entry */
*(unsigned *) (pmap->pm_pdir + PTDPTDI) =
VM_PAGE_TO_PHYS(ptdpg) | PG_V | PG_RW | PG_A | PG_M;
pmap->pm_count = 1;
pmap->pm_active = 0;
pmap->pm_ptphint = NULL;
TAILQ_INIT(&pmap->pm_pvlist);
bzero(&pmap->pm_stats, sizeof pmap->pm_stats);
}
/*
* Wire in kernel global address entries. To avoid a race condition
* between pmap initialization and pmap_growkernel, this procedure
* should be called after the vmspace is attached to the process
* but before this pmap is activated.
*/
void
pmap_pinit2(pmap)
struct pmap *pmap;
{
/* XXX: Remove this stub when no longer called */
}
static int
pmap_release_free_page(pmap, p)
struct pmap *pmap;
vm_page_t p;
{
unsigned *pde = (unsigned *) pmap->pm_pdir;
/*
* This code optimizes the case of freeing non-busy
* page-table pages. Those pages are zero now, and
* might as well be placed directly into the zero queue.
*/
if (vm_page_sleep_busy(p, FALSE, "pmaprl"))
return 0;
vm_page_busy(p);
/*
* Remove the page table page from the processes address space.
*/
pde[p->pindex] = 0;
pmap->pm_stats.resident_count--;
if (p->hold_count) {
panic("pmap_release: freeing held page table page");
}
/*
* Page directory pages need to have the kernel
* stuff cleared, so they can go into the zero queue also.
*/
if (p->pindex == PTDPTDI) {
bzero(pde + KPTDI, nkpt * PTESIZE);
#ifdef SMP
pde[MPPTDI] = 0;
#endif
pde[APTDPTDI] = 0;
pmap_kremove((vm_offset_t) pmap->pm_pdir);
}
if (pmap->pm_ptphint && (pmap->pm_ptphint->pindex == p->pindex))
pmap->pm_ptphint = NULL;
p->wire_count--;
cnt.v_wire_count--;
vm_page_free_zero(p);
return 1;
}
/*
* this routine is called if the page table page is not
* mapped correctly.
*/
static vm_page_t
_pmap_allocpte(pmap, ptepindex)
pmap_t pmap;
unsigned ptepindex;
{
vm_offset_t pteva, ptepa;
vm_page_t m;
/*
* Find or fabricate a new pagetable page
*/
m = vm_page_grab(pmap->pm_pteobj, ptepindex,
VM_ALLOC_ZERO | VM_ALLOC_RETRY);
KASSERT(m->queue == PQ_NONE,
("_pmap_allocpte: %p->queue != PQ_NONE", m));
if (m->wire_count == 0)
cnt.v_wire_count++;
m->wire_count++;
/*
* Increment the hold count for the page table page
* (denoting a new mapping.)
*/
m->hold_count++;
/*
* Map the pagetable page into the process address space, if
* it isn't already there.
*/
pmap->pm_stats.resident_count++;
ptepa = VM_PAGE_TO_PHYS(m);
pmap->pm_pdir[ptepindex] =
(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_A | PG_M);
/*
* Set the page table hint
*/
pmap->pm_ptphint = m;
/*
* Try to use the new mapping, but if we cannot, then
* do it with the routine that maps the page explicitly.
*/
if ((m->flags & PG_ZERO) == 0) {
if ((((unsigned)pmap->pm_pdir[PTDPTDI]) & PG_FRAME) ==
(((unsigned) PTDpde) & PG_FRAME)) {
pteva = UPT_MIN_ADDRESS + i386_ptob(ptepindex);
bzero((caddr_t) pteva, PAGE_SIZE);
} else {
pmap_zero_page(ptepa);
}
}
m->valid = VM_PAGE_BITS_ALL;
vm_page_flag_clear(m, PG_ZERO);
vm_page_flag_set(m, PG_MAPPED);
vm_page_wakeup(m);
return m;
}
static vm_page_t
pmap_allocpte(pmap, va)
pmap_t pmap;
vm_offset_t va;
{
unsigned ptepindex;
vm_offset_t ptepa;
vm_page_t m;
/*
* Calculate pagetable page index
*/
ptepindex = va >> PDRSHIFT;
/*
* Get the page directory entry
*/
ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
/*
* This supports switching from a 4MB page to a
* normal 4K page.
*/
if (ptepa & PG_PS) {
pmap->pm_pdir[ptepindex] = 0;
ptepa = 0;
invltlb();
}
/*
* If the page table page is mapped, we just increment the
* hold count, and activate it.
*/
if (ptepa) {
/*
* In order to get the page table page, try the
* hint first.
*/
if (pmap->pm_ptphint &&
(pmap->pm_ptphint->pindex == ptepindex)) {
m = pmap->pm_ptphint;
} else {
m = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
pmap->pm_ptphint = m;
}
m->hold_count++;
return m;
}
/*
* Here if the pte page isn't mapped, or if it has been deallocated.
*/
return _pmap_allocpte(pmap, ptepindex);
}
/***************************************************
* Pmap allocation/deallocation routines.
***************************************************/
/*
* 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;
{
vm_page_t p,n,ptdpg;
vm_object_t object = pmap->pm_pteobj;
int curgeneration;
#if defined(DIAGNOSTIC)
if (object->ref_count != 1)
panic("pmap_release: pteobj reference count != 1");
#endif
ptdpg = NULL;
LIST_REMOVE(pmap, pm_list);
retry:
curgeneration = object->generation;
for (p = TAILQ_FIRST(&object->memq); p != NULL; p = n) {
n = TAILQ_NEXT(p, listq);
if (p->pindex == PTDPTDI) {
ptdpg = p;
continue;
}
while (1) {
if (!pmap_release_free_page(pmap, p) &&
(object->generation != curgeneration))
goto retry;
}
}
if (ptdpg && !pmap_release_free_page(pmap, ptdpg))
goto retry;
}
/*
* grow the number of kernel page table entries, if needed
*/
void
pmap_growkernel(vm_offset_t addr)
{
struct pmap *pmap;
int s;
vm_offset_t ptppaddr;
vm_page_t nkpg;
pd_entry_t newpdir;
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 + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
nkpt++;
}
}
addr = (addr + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
while (kernel_vm_end < addr) {
if (pdir_pde(PTD, kernel_vm_end)) {
kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * NPTEPG - 1);
continue;
}
/*
* This index is bogus, but out of the way
*/
nkpg = vm_page_alloc(kptobj, nkpt, VM_ALLOC_SYSTEM);
if (!nkpg)
panic("pmap_growkernel: no memory to grow kernel");
nkpt++;
vm_page_wire(nkpg);
ptppaddr = VM_PAGE_TO_PHYS(nkpg);
pmap_zero_page(ptppaddr);
newpdir = (pd_entry_t) (ptppaddr | PG_V | PG_RW | PG_A | PG_M);
pdir_pde(PTD, kernel_vm_end) = newpdir;
LIST_FOREACH(pmap, &allpmaps, pm_list) {
*pmap_pde(pmap, kernel_vm_end) = newpdir;
}
kernel_vm_end = (kernel_vm_end + PAGE_SIZE * NPTEPG) & ~(PAGE_SIZE * 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;
count = --pmap->pm_count;
if (count == 0) {
pmap_release(pmap);
panic("destroying a pmap is not yet implemented");
}
}
/*
* Add a reference to the specified pmap.
*/
void
pmap_reference(pmap)
pmap_t pmap;
{
if (pmap != NULL) {
pmap->pm_count++;
}
}
/***************************************************
* page management routines.
***************************************************/
/*
* free the pv_entry back to the free list
*/
static PMAP_INLINE void
free_pv_entry(pv)
pv_entry_t pv;
{
pv_entry_count--;
zfree(pvzone, 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 pv_entry_t
get_pv_entry(void)
{
pv_entry_count++;
if (pv_entry_high_water &&
(pv_entry_count > pv_entry_high_water) &&
(pmap_pagedaemon_waken == 0)) {
pmap_pagedaemon_waken = 1;
wakeup (&vm_pages_needed);
}
return zalloc(pvzone);
}
/*
* This routine is very drastic, but can save the system
* in a pinch.
*/
void
pmap_collect()
{
int i;
vm_page_t m;
static int warningdone=0;
if (pmap_pagedaemon_waken == 0)
return;
if (warningdone < 5) {
printf("pmap_collect: collecting pv entries -- suggest increasing PMAP_SHPGPERPROC\n");
warningdone++;
}
for(i = 0; i < vm_page_array_size; i++) {
m = &vm_page_array[i];
if (m->wire_count || m->hold_count || m->busy ||
(m->flags & PG_BUSY))
continue;
pmap_remove_all(m);
}
pmap_pagedaemon_waken = 0;
}
/*
* 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.
*/
static int
pmap_remove_entry(pmap, m, va)
struct pmap *pmap;
vm_page_t m;
vm_offset_t va;
{
pv_entry_t pv;
int rtval;
int s;
s = splvm();
if (m->md.pv_list_count < pmap->pm_stats.resident_count) {
for (pv = TAILQ_FIRST(&m->md.pv_list);
pv;
pv = TAILQ_NEXT(pv, pv_list)) {
if (pmap == pv->pv_pmap && va == pv->pv_va)
break;
}
} else {
for (pv = TAILQ_FIRST(&pmap->pm_pvlist);
pv;
pv = TAILQ_NEXT(pv, pv_plist)) {
if (va == pv->pv_va)
break;
}
}
rtval = 0;
if (pv) {
rtval = pmap_unuse_pt(pmap, va, pv->pv_ptem);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
m->md.pv_list_count--;
if (TAILQ_FIRST(&m->md.pv_list) == NULL)
vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
TAILQ_REMOVE(&pmap->pm_pvlist, pv, pv_plist);
free_pv_entry(pv);
}
splx(s);
return rtval;
}
/*
* Create a pv entry for page at pa for
* (pmap, va).
*/
static void
pmap_insert_entry(pmap, va, mpte, m)
pmap_t pmap;
vm_offset_t va;
vm_page_t mpte;
vm_page_t m;
{
int s;
pv_entry_t pv;
s = splvm();
pv = get_pv_entry();
pv->pv_va = va;
pv->pv_pmap = pmap;
pv->pv_ptem = mpte;
TAILQ_INSERT_TAIL(&pmap->pm_pvlist, pv, pv_plist);
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
m->md.pv_list_count++;
splx(s);
}
/*
* pmap_remove_pte: do the things to unmap a page in a process
*/
static int
pmap_remove_pte(pmap, ptq, va)
struct pmap *pmap;
unsigned *ptq;
vm_offset_t va;
{
unsigned oldpte;
vm_page_t m;
oldpte = atomic_readandclear_int(ptq);
if (oldpte & PG_W)
pmap->pm_stats.wired_count -= 1;
/*
* Machines that don't support invlpg, also don't support
* PG_G.
*/
if (oldpte & PG_G)
invlpg(va);
pmap->pm_stats.resident_count -= 1;
if (oldpte & PG_MANAGED) {
m = PHYS_TO_VM_PAGE(oldpte);
if (oldpte & PG_M) {
#if defined(PMAP_DIAGNOSTIC)
if (pmap_nw_modified((pt_entry_t) oldpte)) {
printf(
"pmap_remove: modified page not writable: va: 0x%x, pte: 0x%x\n",
va, oldpte);
}
#endif
if (pmap_track_modified(va))
vm_page_dirty(m);
}
if (oldpte & PG_A)
vm_page_flag_set(m, PG_REFERENCED);
return pmap_remove_entry(pmap, m, va);
} else {
return pmap_unuse_pt(pmap, va, NULL);
}
return 0;
}
/*
* Remove a single page from a process address space
*/
static void
pmap_remove_page(pmap, va)
struct pmap *pmap;
register vm_offset_t va;
{
register unsigned *ptq;
/*
* if there is no pte for this address, just skip it!!!
*/
if (*pmap_pde(pmap, va) == 0) {
return;
}
/*
* get a local va for mappings for this pmap.
*/
ptq = get_ptbase(pmap) + i386_btop(va);
if (*ptq) {
(void) pmap_remove_pte(pmap, ptq, va);
pmap_TLB_invalidate(pmap, va);
}
return;
}
/*
* 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 unsigned *ptbase;
vm_offset_t pdnxt;
vm_offset_t ptpaddr;
vm_offset_t sindex, eindex;
int anyvalid;
if (pmap == NULL)
return;
if (pmap->pm_stats.resident_count == 0)
return;
/*
* special handling of removing one page. a very
* common operation and easy to short circuit some
* code.
*/
if (((sva + PAGE_SIZE) == eva) &&
(((unsigned) pmap->pm_pdir[(sva >> PDRSHIFT)] & PG_PS) == 0)) {
pmap_remove_page(pmap, sva);
return;
}
anyvalid = 0;
/*
* Get a local virtual address for the mappings that are being
* worked with.
*/
ptbase = get_ptbase(pmap);
sindex = i386_btop(sva);
eindex = i386_btop(eva);
for (; sindex < eindex; sindex = pdnxt) {
unsigned pdirindex;
/*
* Calculate index for next page table.
*/
pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
if (pmap->pm_stats.resident_count == 0)
break;
pdirindex = sindex / NPDEPG;
if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
pmap->pm_pdir[pdirindex] = 0;
pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
anyvalid++;
continue;
}
/*
* Weed out invalid mappings. Note: we assume that the page
* directory table is always allocated, and in kernel virtual.
*/
if (ptpaddr == 0)
continue;
/*
* Limit our scan to either the end of the va represented
* by the current page table page, or to the end of the
* range being removed.
*/
if (pdnxt > eindex) {
pdnxt = eindex;
}
for ( ;sindex != pdnxt; sindex++) {
vm_offset_t va;
if (ptbase[sindex] == 0) {
continue;
}
va = i386_ptob(sindex);
anyvalid++;
if (pmap_remove_pte(pmap,
ptbase + sindex, va))
break;
}
}
if (anyvalid)
pmap_TLB_invalidate_all(pmap);
}
/*
* 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...)
*/
static void
pmap_remove_all(m)
vm_page_t m;
{
register pv_entry_t pv;
register unsigned *pte, tpte;
int s;
#if defined(PMAP_DIAGNOSTIC)
/*
* XXX this makes pmap_page_protect(NONE) illegal for non-managed
* pages!
*/
if (!pmap_initialized || (m->flags & PG_FICTITIOUS)) {
panic("pmap_page_protect: illegal for unmanaged page, va: 0x%x", VM_PAGE_TO_PHYS(m));
}
#endif
s = splvm();
while ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
pv->pv_pmap->pm_stats.resident_count--;
pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
tpte = atomic_readandclear_int(pte);
if (tpte & PG_W)
pv->pv_pmap->pm_stats.wired_count--;
if (tpte & PG_A)
vm_page_flag_set(m, PG_REFERENCED);
/*
* Update the vm_page_t clean and reference bits.
*/
if (tpte & PG_M) {
#if defined(PMAP_DIAGNOSTIC)
if (pmap_nw_modified((pt_entry_t) tpte)) {
printf(
"pmap_remove_all: modified page not writable: va: 0x%x, pte: 0x%x\n",
pv->pv_va, tpte);
}
#endif
if (pmap_track_modified(pv->pv_va))
vm_page_dirty(m);
}
pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
m->md.pv_list_count--;
pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
free_pv_entry(pv);
}
vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
splx(s);
}
/*
* Set the physical protection on the
* specified range of this map as requested.
*/
void
pmap_protect(pmap_t pmap, vm_offset_t sva, vm_offset_t eva, vm_prot_t prot)
{
register unsigned *ptbase;
vm_offset_t pdnxt, ptpaddr;
vm_pindex_t sindex, eindex;
int anychanged;
if (pmap == NULL)
return;
if ((prot & VM_PROT_READ) == VM_PROT_NONE) {
pmap_remove(pmap, sva, eva);
return;
}
if (prot & VM_PROT_WRITE)
return;
anychanged = 0;
ptbase = get_ptbase(pmap);
sindex = i386_btop(sva);
eindex = i386_btop(eva);
for (; sindex < eindex; sindex = pdnxt) {
unsigned pdirindex;
pdnxt = ((sindex + NPTEPG) & ~(NPTEPG - 1));
pdirindex = sindex / NPDEPG;
if (((ptpaddr = (unsigned) pmap->pm_pdir[pdirindex]) & PG_PS) != 0) {
(unsigned) pmap->pm_pdir[pdirindex] &= ~(PG_M|PG_RW);
pmap->pm_stats.resident_count -= NBPDR / PAGE_SIZE;
anychanged++;
continue;
}
/*
* Weed out invalid mappings. Note: we assume that the page
* directory table is always allocated, and in kernel virtual.
*/
if (ptpaddr == 0)
continue;
if (pdnxt > eindex) {
pdnxt = eindex;
}
for (; sindex != pdnxt; sindex++) {
unsigned pbits;
vm_page_t m;
pbits = ptbase[sindex];
if (pbits & PG_MANAGED) {
m = NULL;
if (pbits & PG_A) {
m = PHYS_TO_VM_PAGE(pbits);
vm_page_flag_set(m, PG_REFERENCED);
pbits &= ~PG_A;
}
if (pbits & PG_M) {
if (pmap_track_modified(i386_ptob(sindex))) {
if (m == NULL)
m = PHYS_TO_VM_PAGE(pbits);
vm_page_dirty(m);
pbits &= ~PG_M;
}
}
}
pbits &= ~PG_RW;
if (pbits != ptbase[sindex]) {
ptbase[sindex] = pbits;
anychanged = 1;
}
}
}
if (anychanged)
pmap_TLB_invalidate_all(pmap);
}
/*
* 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_t pmap, vm_offset_t va, vm_page_t m, vm_prot_t prot,
boolean_t wired)
{
vm_offset_t pa;
register unsigned *pte;
vm_offset_t opa;
vm_offset_t origpte, newpte;
vm_page_t mpte;
if (pmap == NULL)
return;
va &= PG_FRAME;
#ifdef PMAP_DIAGNOSTIC
if (va > VM_MAX_KERNEL_ADDRESS)
panic("pmap_enter: toobig");
if ((va >= UPT_MIN_ADDRESS) && (va < UPT_MAX_ADDRESS))
panic("pmap_enter: invalid to pmap_enter page table pages (va: 0x%x)", va);
#endif
mpte = NULL;
/*
* In the case that a page table page is not
* resident, we are creating it here.
*/
if (va < UPT_MIN_ADDRESS) {
mpte = pmap_allocpte(pmap, va);
}
#if 0 && defined(PMAP_DIAGNOSTIC)
else {
vm_offset_t *pdeaddr = (vm_offset_t *)pmap_pde(pmap, va);
if (((origpte = (vm_offset_t) *pdeaddr) & PG_V) == 0) {
panic("pmap_enter: invalid kernel page table page(0), pdir=%p, pde=%p, va=%p\n",
pmap->pm_pdir[PTDPTDI], origpte, va);
}
if (smp_active) {
pdeaddr = (vm_offset_t *) IdlePTDS[PCPU_GET(cpuid)];
if (((newpte = pdeaddr[va >> PDRSHIFT]) & PG_V) == 0) {
if ((vm_offset_t) my_idlePTD != (vm_offset_t) vtophys(pdeaddr))
printf("pde mismatch: %x, %x\n", my_idlePTD, pdeaddr);
printf("cpuid: %d, pdeaddr: 0x%x\n", PCPU_GET(cpuid), pdeaddr);
panic("pmap_enter: invalid kernel page table page(1), pdir=%p, npde=%p, pde=%p, va=%p\n",
pmap->pm_pdir[PTDPTDI], newpte, origpte, va);
}
}
}
#endif
pte = pmap_pte(pmap, va);
/*
* Page Directory table entry not valid, we need a new PT page
*/
if (pte == NULL) {
panic("pmap_enter: invalid page directory, pdir=%p, va=0x%x\n",
(void *)pmap->pm_pdir[PTDPTDI], va);
}
pa = VM_PAGE_TO_PHYS(m) & PG_FRAME;
origpte = *(vm_offset_t *)pte;
opa = origpte & PG_FRAME;
if (origpte & PG_PS)
panic("pmap_enter: attempted pmap_enter on 4MB page");
/*
* Mapping has not changed, must be protection or wiring change.
*/
if (origpte && (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 && ((origpte & PG_W) == 0))
pmap->pm_stats.wired_count++;
else if (!wired && (origpte & PG_W))
pmap->pm_stats.wired_count--;
#if defined(PMAP_DIAGNOSTIC)
if (pmap_nw_modified((pt_entry_t) origpte)) {
printf(
"pmap_enter: modified page not writable: va: 0x%x, pte: 0x%x\n",
va, origpte);
}
#endif
/*
* Remove extra pte reference
*/
if (mpte)
mpte->hold_count--;
if ((prot & VM_PROT_WRITE) && (origpte & PG_V)) {
if ((origpte & PG_RW) == 0) {
*pte |= PG_RW;
#ifdef SMP
cpu_invlpg((void *)va);
if (pmap->pm_active & PCPU_GET(other_cpus))
smp_invltlb();
#else
invltlb_1pg(va);
#endif
}
return;
}
/*
* We might be turning off write access to the page,
* so we go ahead and sense modify status.
*/
if (origpte & PG_MANAGED) {
if ((origpte & PG_M) && pmap_track_modified(va)) {
vm_page_t om;
om = PHYS_TO_VM_PAGE(opa);
vm_page_dirty(om);
}
pa |= PG_MANAGED;
}
goto validate;
}
/*
* Mapping has changed, invalidate old range and fall through to
* handle validating new mapping.
*/
if (opa) {
int err;
err = pmap_remove_pte(pmap, pte, va);
if (err)
panic("pmap_enter: pte vanished, va: 0x%x", va);
}
/*
* 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_initialized &&
(m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0) {
pmap_insert_entry(pmap, va, mpte, m);
pa |= PG_MANAGED;
}
/*
* Increment counters
*/
pmap->pm_stats.resident_count++;
if (wired)
pmap->pm_stats.wired_count++;
validate:
/*
* Now validate mapping with desired protection/wiring.
*/
newpte = (vm_offset_t) (pa | pte_prot(pmap, prot) | PG_V);
if (wired)
newpte |= PG_W;
if (va < UPT_MIN_ADDRESS)
newpte |= PG_U;
if (pmap == kernel_pmap)
newpte |= pgeflag;
/*
* if the mapping or permission bits are different, we need
* to update the pte.
*/
if ((origpte & ~(PG_M|PG_A)) != newpte) {
*pte = newpte | PG_A;
/*if (origpte)*/ {
#ifdef SMP
cpu_invlpg((void *)va);
if (pmap->pm_active & PCPU_GET(other_cpus))
smp_invltlb();
#else
invltlb_1pg(va);
#endif
}
}
}
/*
* 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 vm_page_t
pmap_enter_quick(pmap, va, m, mpte)
register pmap_t pmap;
vm_offset_t va;
vm_page_t m;
vm_page_t mpte;
{
unsigned *pte;
vm_offset_t pa;
/*
* In the case that a page table page is not
* resident, we are creating it here.
*/
if (va < UPT_MIN_ADDRESS) {
unsigned ptepindex;
vm_offset_t ptepa;
/*
* Calculate pagetable page index
*/
ptepindex = va >> PDRSHIFT;
if (mpte && (mpte->pindex == ptepindex)) {
mpte->hold_count++;
} else {
retry:
/*
* Get the page directory entry
*/
ptepa = (vm_offset_t) pmap->pm_pdir[ptepindex];
/*
* If the page table page is mapped, we just increment
* the hold count, and activate it.
*/
if (ptepa) {
if (ptepa & PG_PS)
panic("pmap_enter_quick: unexpected mapping into 4MB page");
if (pmap->pm_ptphint &&
(pmap->pm_ptphint->pindex == ptepindex)) {
mpte = pmap->pm_ptphint;
} else {
mpte = pmap_page_lookup( pmap->pm_pteobj, ptepindex);
pmap->pm_ptphint = mpte;
}
if (mpte == NULL)
goto retry;
mpte->hold_count++;
} else {
mpte = _pmap_allocpte(pmap, ptepindex);
}
}
} else {
mpte = NULL;
}
/*
* This call to vtopte makes the assumption that we are
* entering the page into the current pmap. In order to support
* quick entry into any pmap, one would likely use pmap_pte_quick.
* But that isn't as quick as vtopte.
*/
pte = (unsigned *)vtopte(va);
if (*pte) {
if (mpte)
pmap_unwire_pte_hold(pmap, mpte);
return 0;
}
/*
* 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 ((m->flags & (PG_FICTITIOUS|PG_UNMANAGED)) == 0)
pmap_insert_entry(pmap, va, mpte, m);
/*
* Increment counters
*/
pmap->pm_stats.resident_count++;
pa = VM_PAGE_TO_PHYS(m);
/*
* Now validate mapping with RO protection
*/
if (m->flags & (PG_FICTITIOUS|PG_UNMANAGED))
*pte = pa | PG_V | PG_U;
else
*pte = pa | PG_V | PG_U | PG_MANAGED;
return mpte;
}
/*
* Make a temporary mapping for a physical address. This is only intended
* to be used for panic dumps.
*/
void *
pmap_kenter_temporary(vm_offset_t pa, int i)
{
pmap_kenter((vm_offset_t)crashdumpmap + (i * PAGE_SIZE), pa);
return ((void *)crashdumpmap);
}
#define MAX_INIT_PT (96)
/*
* 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, pindex, size, limit)
pmap_t pmap;
vm_offset_t addr;
vm_object_t object;
vm_pindex_t pindex;
vm_size_t size;
int limit;
{
vm_offset_t tmpidx;
int psize;
vm_page_t p, mpte;
int objpgs;
if (pmap == NULL || object == NULL)
return;
/*
* This code maps large physical mmap regions into the
* processor address space. Note that some shortcuts
* are taken, but the code works.
*/
if (pseflag &&
(object->type == OBJT_DEVICE) &&
((addr & (NBPDR - 1)) == 0) &&
((size & (NBPDR - 1)) == 0) ) {
int i;
vm_page_t m[1];
unsigned int ptepindex;
int npdes;
vm_offset_t ptepa;
if (pmap->pm_pdir[ptepindex = (addr >> PDRSHIFT)])
return;
retry:
p = vm_page_lookup(object, pindex);
if (p && vm_page_sleep_busy(p, FALSE, "init4p"))
goto retry;
if (p == NULL) {
p = vm_page_alloc(object, pindex, VM_ALLOC_NORMAL);
if (p == NULL)
return;
m[0] = p;
if (vm_pager_get_pages(object, m, 1, 0) != VM_PAGER_OK) {
vm_page_free(p);
return;
}
p = vm_page_lookup(object, pindex);
vm_page_wakeup(p);
}
ptepa = (vm_offset_t) VM_PAGE_TO_PHYS(p);
if (ptepa & (NBPDR - 1)) {
return;
}
p->valid = VM_PAGE_BITS_ALL;
pmap->pm_stats.resident_count += size >> PAGE_SHIFT;
npdes = size >> PDRSHIFT;
for(i=0;i<npdes;i++) {
pmap->pm_pdir[ptepindex] =
(pd_entry_t) (ptepa | PG_U | PG_RW | PG_V | PG_PS);
ptepa += NBPDR;
ptepindex += 1;
}
vm_page_flag_set(p, PG_MAPPED);
invltlb();
return;
}
psize = i386_btop(size);
if ((object->type != OBJT_VNODE) ||
(limit && (psize > MAX_INIT_PT) &&
(object->resident_page_count > MAX_INIT_PT))) {
return;
}
if (psize + pindex > object->size) {
if (object->size < pindex)
return;
psize = object->size - pindex;
}
mpte = NULL;
/*
* if we are processing a major portion of the object, then scan the
* entire thing.
*/
if (psize > (object->resident_page_count >> 2)) {
objpgs = psize;
for (p = TAILQ_FIRST(&object->memq);
((objpgs > 0) && (p != NULL));
p = TAILQ_NEXT(p, listq)) {
tmpidx = p->pindex;
if (tmpidx < pindex) {
continue;
}
tmpidx -= pindex;
if (tmpidx >= psize) {
continue;
}
if (((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(p->busy == 0) &&
(p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
if ((p->queue - p->pc) == PQ_CACHE)
vm_page_deactivate(p);
vm_page_busy(p);
mpte = pmap_enter_quick(pmap,
addr + i386_ptob(tmpidx), p, mpte);
vm_page_flag_set(p, PG_MAPPED);
vm_page_wakeup(p);
}
objpgs -= 1;
}
} else {
/*
* else lookup the pages one-by-one.
*/
for (tmpidx = 0; tmpidx < psize; tmpidx += 1) {
p = vm_page_lookup(object, tmpidx + pindex);
if (p &&
((p->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(p->busy == 0) &&
(p->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
if ((p->queue - p->pc) == PQ_CACHE)
vm_page_deactivate(p);
vm_page_busy(p);
mpte = pmap_enter_quick(pmap,
addr + i386_ptob(tmpidx), p, mpte);
vm_page_flag_set(p, PG_MAPPED);
vm_page_wakeup(p);
}
}
}
return;
}
/*
* 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 4
#define PFFOR 4
#define PAGEORDER_SIZE (PFBAK+PFFOR)
static int pmap_prefault_pageorder[] = {
-PAGE_SIZE, PAGE_SIZE,
-2 * PAGE_SIZE, 2 * PAGE_SIZE,
-3 * PAGE_SIZE, 3 * PAGE_SIZE
-4 * PAGE_SIZE, 4 * PAGE_SIZE
};
void
pmap_prefault(pmap, addra, entry)
pmap_t pmap;
vm_offset_t addra;
vm_map_entry_t entry;
{
int i;
vm_offset_t starta;
vm_offset_t addr;
vm_pindex_t pindex;
vm_page_t m, mpte;
vm_object_t object;
if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace)))
return;
object = entry->object.vm_object;
starta = addra - PFBAK * PAGE_SIZE;
if (starta < entry->start) {
starta = entry->start;
} else if (starta > addra) {
starta = 0;
}
mpte = NULL;
for (i = 0; i < PAGEORDER_SIZE; i++) {
vm_object_t lobject;
unsigned *pte;
addr = addra + pmap_prefault_pageorder[i];
if (addr > addra + (PFFOR * PAGE_SIZE))
addr = 0;
if (addr < starta || addr >= entry->end)
continue;
if ((*pmap_pde(pmap, addr)) == NULL)
continue;
pte = (unsigned *) vtopte(addr);
if (*pte)
continue;
pindex = ((addr - entry->start) + entry->offset) >> PAGE_SHIFT;
lobject = object;
for (m = vm_page_lookup(lobject, pindex);
(!m && (lobject->type == OBJT_DEFAULT) && (lobject->backing_object));
lobject = lobject->backing_object) {
if (lobject->backing_object_offset & PAGE_MASK)
break;
pindex += (lobject->backing_object_offset >> PAGE_SHIFT);
m = vm_page_lookup(lobject->backing_object, pindex);
}
/*
* give-up when a page is not in memory
*/
if (m == NULL)
break;
if (((m->valid & VM_PAGE_BITS_ALL) == VM_PAGE_BITS_ALL) &&
(m->busy == 0) &&
(m->flags & (PG_BUSY | PG_FICTITIOUS)) == 0) {
if ((m->queue - m->pc) == PQ_CACHE) {
vm_page_deactivate(m);
}
vm_page_busy(m);
mpte = pmap_enter_quick(pmap, addr, m, mpte);
vm_page_flag_set(m, PG_MAPPED);
vm_page_wakeup(m);
}
}
}
/*
* 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 unsigned *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);
}
/*
* 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;
{
vm_offset_t addr;
vm_offset_t end_addr = src_addr + len;
vm_offset_t pdnxt;
unsigned src_frame, dst_frame;
vm_page_t m;
if (dst_addr != src_addr)
return;
src_frame = ((unsigned) src_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
if (src_frame != (((unsigned) PTDpde) & PG_FRAME)) {
return;
}
dst_frame = ((unsigned) dst_pmap->pm_pdir[PTDPTDI]) & PG_FRAME;
if (dst_frame != (((unsigned) APTDpde) & PG_FRAME)) {
APTDpde = (pd_entry_t) (dst_frame | PG_RW | PG_V);
#if defined(SMP)
/* The page directory is not shared between CPUs */
cpu_invltlb();
#else
invltlb();
#endif
}
for(addr = src_addr; addr < end_addr; addr = pdnxt) {
unsigned *src_pte, *dst_pte;
vm_page_t dstmpte, srcmpte;
vm_offset_t srcptepaddr;
unsigned ptepindex;
if (addr >= UPT_MIN_ADDRESS)
panic("pmap_copy: invalid to pmap_copy page tables\n");
/*
* Don't let optional prefaulting of pages make us go
* way below the low water mark of free pages or way
* above high water mark of used pv entries.
*/
if (cnt.v_free_count < cnt.v_free_reserved ||
pv_entry_count > pv_entry_high_water)
break;
pdnxt = ((addr + PAGE_SIZE*NPTEPG) & ~(PAGE_SIZE*NPTEPG - 1));
ptepindex = addr >> PDRSHIFT;
srcptepaddr = (vm_offset_t) src_pmap->pm_pdir[ptepindex];
if (srcptepaddr == 0)
continue;
if (srcptepaddr & PG_PS) {
if (dst_pmap->pm_pdir[ptepindex] == 0) {
dst_pmap->pm_pdir[ptepindex] = (pd_entry_t) srcptepaddr;
dst_pmap->pm_stats.resident_count += NBPDR / PAGE_SIZE;
}
continue;
}
srcmpte = vm_page_lookup(src_pmap->pm_pteobj, ptepindex);
if ((srcmpte == NULL) ||
(srcmpte->hold_count == 0) || (srcmpte->flags & PG_BUSY))
continue;
if (pdnxt > end_addr)
pdnxt = end_addr;
src_pte = (unsigned *) vtopte(addr);
dst_pte = (unsigned *) avtopte(addr);
while (addr < pdnxt) {
unsigned ptetemp;
ptetemp = *src_pte;
/*
* we only virtual copy managed pages
*/
if ((ptetemp & PG_MANAGED) != 0) {
/*
* We have to check after allocpte for the
* pte still being around... allocpte can
* block.
*/
dstmpte = pmap_allocpte(dst_pmap, addr);
if ((*dst_pte == 0) && (ptetemp = *src_pte)) {
/*
* Clear the modified and
* accessed (referenced) bits
* during the copy.
*/
m = PHYS_TO_VM_PAGE(ptetemp);
*dst_pte = ptetemp & ~(PG_M | PG_A);
dst_pmap->pm_stats.resident_count++;
pmap_insert_entry(dst_pmap, addr,
dstmpte, m);
} else {
pmap_unwire_pte_hold(dst_pmap, dstmpte);
}
if (dstmpte->hold_count >= srcmpte->hold_count)
break;
}
addr += PAGE_SIZE;
src_pte++;
dst_pte++;
}
}
}
/*
* 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 hardware page by mapping
* the page into KVM and using bzero to clear its contents.
*/
void
pmap_zero_page(phys)
vm_offset_t phys;
{
if (*(int *) CMAP2)
panic("pmap_zero_page: CMAP2 busy");
*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
invltlb_1pg((vm_offset_t)CADDR2);
#if defined(I686_CPU)
if (cpu_class == CPUCLASS_686)
i686_pagezero(CADDR2);
else
#endif
bzero(CADDR2, PAGE_SIZE);
*(int *) CMAP2 = 0;
}
/*
* pmap_zero_page_area zeros the specified hardware page by mapping
* the page into KVM and using bzero to clear its contents.
*
* off and size may not cover an area beyond a single hardware page.
*/
void
pmap_zero_page_area(phys, off, size)
vm_offset_t phys;
int off;
int size;
{
if (*(int *) CMAP2)
panic("pmap_zero_page: CMAP2 busy");
*(int *) CMAP2 = PG_V | PG_RW | (phys & PG_FRAME) | PG_A | PG_M;
invltlb_1pg((vm_offset_t)CADDR2);
#if defined(I686_CPU)
if (cpu_class == CPUCLASS_686 && off == 0 && size == PAGE_SIZE)
i686_pagezero(CADDR2);
else
#endif
bzero((char *)CADDR2 + off, size);
*(int *) CMAP2 = 0;
}
/*
* 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)
panic("pmap_copy_page: CMAP1 busy");
if (*(int *) CMAP2)
panic("pmap_copy_page: CMAP2 busy");
*(int *) CMAP1 = PG_V | (src & PG_FRAME) | PG_A;
*(int *) CMAP2 = PG_V | PG_RW | (dst & PG_FRAME) | PG_A | PG_M;
#ifdef I386_CPU
invltlb();
#else
invlpg((u_int)CADDR1);
invlpg((u_int)CADDR2);
#endif
bcopy(CADDR1, CADDR2, PAGE_SIZE);
*(int *) CMAP1 = 0;
*(int *) CMAP2 = 0;
}
/*
* 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, m)
pmap_t pmap;
vm_page_t m;
{
register pv_entry_t pv;
int s;
if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
return FALSE;
s = splvm();
/*
* Not found, check current mappings returning immediately if found.
*/
for (pv = TAILQ_FIRST(&m->md.pv_list);
pv;
pv = TAILQ_NEXT(pv, pv_list)) {
if (pv->pv_pmap == pmap) {
splx(s);
return TRUE;
}
}
splx(s);
return (FALSE);
}
#define PMAP_REMOVE_PAGES_CURPROC_ONLY
/*
* Remove all pages from specified address space
* this aids process exit speeds. Also, this code
* is special cased for current process only, but
* can have the more generic (and slightly slower)
* mode enabled. This is much faster than pmap_remove
* in the case of running down an entire address space.
*/
void
pmap_remove_pages(pmap, sva, eva)
pmap_t pmap;
vm_offset_t sva, eva;
{
unsigned *pte, tpte;
pv_entry_t pv, npv;
int s;
vm_page_t m;
#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
if (!curproc || (pmap != vmspace_pmap(curproc->p_vmspace))) {
printf("warning: pmap_remove_pages called with non-current pmap\n");
return;
}
#endif
s = splvm();
for(pv = TAILQ_FIRST(&pmap->pm_pvlist);
pv;
pv = npv) {
if (pv->pv_va >= eva || pv->pv_va < sva) {
npv = TAILQ_NEXT(pv, pv_plist);
continue;
}
#ifdef PMAP_REMOVE_PAGES_CURPROC_ONLY
pte = (unsigned *)vtopte(pv->pv_va);
#else
pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
#endif
tpte = *pte;
/*
* We cannot remove wired pages from a process' mapping at this time
*/
if (tpte & PG_W) {
npv = TAILQ_NEXT(pv, pv_plist);
continue;
}
*pte = 0;
m = PHYS_TO_VM_PAGE(tpte);
KASSERT(m < &vm_page_array[vm_page_array_size],
("pmap_remove_pages: bad tpte %x", tpte));
pv->pv_pmap->pm_stats.resident_count--;
/*
* Update the vm_page_t clean and reference bits.
*/
if (tpte & PG_M) {
vm_page_dirty(m);
}
npv = TAILQ_NEXT(pv, pv_plist);
TAILQ_REMOVE(&pv->pv_pmap->pm_pvlist, pv, pv_plist);
m->md.pv_list_count--;
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
if (TAILQ_FIRST(&m->md.pv_list) == NULL) {
vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
}
pmap_unuse_pt(pv->pv_pmap, pv->pv_va, pv->pv_ptem);
free_pv_entry(pv);
}
splx(s);
pmap_TLB_invalidate_all(pmap);
}
/*
* pmap_testbit tests bits in pte's
* note that the testbit/changebit routines are inline,
* and a lot of things compile-time evaluate.
*/
static boolean_t
pmap_testbit(m, bit)
vm_page_t m;
int bit;
{
pv_entry_t pv;
unsigned *pte;
int s;
if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
return FALSE;
if (TAILQ_FIRST(&m->md.pv_list) == NULL)
return FALSE;
s = splvm();
for (pv = TAILQ_FIRST(&m->md.pv_list);
pv;
pv = TAILQ_NEXT(pv, pv_list)) {
/*
* if the bit being tested is the modified bit, then
* mark clean_map and ptes as never
* modified.
*/
if (bit & (PG_A|PG_M)) {
if (!pmap_track_modified(pv->pv_va))
continue;
}
#if defined(PMAP_DIAGNOSTIC)
if (!pv->pv_pmap) {
printf("Null pmap (tb) at va: 0x%x\n", pv->pv_va);
continue;
}
#endif
pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
if (*pte & bit) {
splx(s);
return TRUE;
}
}
splx(s);
return (FALSE);
}
/*
* this routine is used to modify bits in ptes
*/
static __inline void
pmap_changebit(m, bit, setem)
vm_page_t m;
int bit;
boolean_t setem;
{
register pv_entry_t pv;
register unsigned *pte;
int s;
if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
return;
s = splvm();
/*
* Loop over all current mappings setting/clearing as appropos If
* setting RO do we need to clear the VAC?
*/
for (pv = TAILQ_FIRST(&m->md.pv_list);
pv;
pv = TAILQ_NEXT(pv, pv_list)) {
/*
* don't write protect pager mappings
*/
if (!setem && (bit == PG_RW)) {
if (!pmap_track_modified(pv->pv_va))
continue;
}
#if defined(PMAP_DIAGNOSTIC)
if (!pv->pv_pmap) {
printf("Null pmap (cb) at va: 0x%x\n", pv->pv_va);
continue;
}
#endif
pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
if (setem) {
*(int *)pte |= bit;
pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
} else {
vm_offset_t pbits = *(vm_offset_t *)pte;
if (pbits & bit) {
if (bit == PG_RW) {
if (pbits & PG_M) {
vm_page_dirty(m);
}
*(int *)pte = pbits & ~(PG_M|PG_RW);
} else {
*(int *)pte = pbits & ~bit;
}
pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
}
}
}
splx(s);
}
/*
* pmap_page_protect:
*
* Lower the permission for all mappings to a given page.
*/
void
pmap_page_protect(vm_page_t m, vm_prot_t prot)
{
if ((prot & VM_PROT_WRITE) == 0) {
if (prot & (VM_PROT_READ | VM_PROT_EXECUTE)) {
pmap_changebit(m, PG_RW, FALSE);
} else {
pmap_remove_all(m);
}
}
}
vm_offset_t
pmap_phys_address(ppn)
int ppn;
{
return (i386_ptob(ppn));
}
/*
* pmap_ts_referenced:
*
* Return the count of reference bits for a page, clearing all of them.
*/
int
pmap_ts_referenced(vm_page_t m)
{
register pv_entry_t pv, pvf, pvn;
unsigned *pte;
int s;
int rtval = 0;
if (!pmap_initialized || (m->flags & PG_FICTITIOUS))
return (rtval);
s = splvm();
if ((pv = TAILQ_FIRST(&m->md.pv_list)) != NULL) {
pvf = pv;
do {
pvn = TAILQ_NEXT(pv, pv_list);
TAILQ_REMOVE(&m->md.pv_list, pv, pv_list);
TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_list);
if (!pmap_track_modified(pv->pv_va))
continue;
pte = pmap_pte_quick(pv->pv_pmap, pv->pv_va);
if (pte && (*pte & PG_A)) {
*pte &= ~PG_A;
pmap_TLB_invalidate(pv->pv_pmap, pv->pv_va);
rtval++;
if (rtval > 4) {
break;
}
}
} while ((pv = pvn) != NULL && pv != pvf);
}
splx(s);
return (rtval);
}
/*
* pmap_is_modified:
*
* Return whether or not the specified physical page was modified
* in any physical maps.
*/
boolean_t
pmap_is_modified(vm_page_t m)
{
return pmap_testbit(m, PG_M);
}
/*
* Clear the modify bits on the specified physical page.
*/
void
pmap_clear_modify(vm_page_t m)
{
pmap_changebit(m, PG_M, FALSE);
}
/*
* pmap_clear_reference:
*
* Clear the reference bit on the specified physical page.
*/
void
pmap_clear_reference(vm_page_t m)
{
pmap_changebit(m, PG_A, FALSE);
}
/*
* Miscellaneous support routines follow
*/
static 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.
*/
void *
pmap_mapdev(pa, size)
vm_offset_t pa;
vm_size_t size;
{
vm_offset_t va, tmpva, offset;
unsigned *pte;
int hadvmlock;
offset = pa & PAGE_MASK;
size = roundup(offset + size, PAGE_SIZE);
hadvmlock = mtx_owned(&vm_mtx);
if (!hadvmlock)
mtx_lock(&vm_mtx);
va = kmem_alloc_pageable(kernel_map, size);
if (!va)
panic("pmap_mapdev: Couldn't alloc kernel virtual memory");
pa = pa & PG_FRAME;
for (tmpva = va; size > 0;) {
pte = (unsigned *)vtopte(tmpva);
*pte = pa | PG_RW | PG_V | pgeflag;
size -= PAGE_SIZE;
tmpva += PAGE_SIZE;
pa += PAGE_SIZE;
}
invltlb();
if (!hadvmlock)
mtx_unlock(&vm_mtx);
return ((void *)(va + offset));
}
void
pmap_unmapdev(va, size)
vm_offset_t va;
vm_size_t size;
{
vm_offset_t base, offset;
base = va & PG_FRAME;
offset = va & PAGE_MASK;
size = roundup(offset + size, PAGE_SIZE);
kmem_free(kernel_map, base, size);
}
/*
* perform the pmap work for mincore
*/
int
pmap_mincore(pmap, addr)
pmap_t pmap;
vm_offset_t addr;
{
unsigned *ptep, pte;
vm_page_t m;
int val = 0;
ptep = pmap_pte(pmap, addr);
if (ptep == 0) {
return 0;
}
if ((pte = *ptep) != 0) {
vm_offset_t pa;
val = MINCORE_INCORE;
if ((pte & PG_MANAGED) == 0)
return val;
pa = pte & PG_FRAME;
m = PHYS_TO_VM_PAGE(pa);
/*
* Modified by us
*/
if (pte & PG_M)
val |= MINCORE_MODIFIED|MINCORE_MODIFIED_OTHER;
/*
* Modified by someone
*/
else if (m->dirty || pmap_is_modified(m))
val |= MINCORE_MODIFIED_OTHER;
/*
* Referenced by us
*/
if (pte & PG_A)
val |= MINCORE_REFERENCED|MINCORE_REFERENCED_OTHER;
/*
* Referenced by someone
*/
else if ((m->flags & PG_REFERENCED) || pmap_ts_referenced(m)) {
val |= MINCORE_REFERENCED_OTHER;
vm_page_flag_set(m, PG_REFERENCED);
}
}
return val;
}
void
pmap_activate(struct proc *p)
{
pmap_t pmap;
pmap = vmspace_pmap(p->p_vmspace);
#if defined(SMP)
pmap->pm_active |= 1 << PCPU_GET(cpuid);
#else
pmap->pm_active |= 1;
#endif
#if defined(SWTCH_OPTIM_STATS)
tlb_flush_count++;
#endif
load_cr3(p->p_addr->u_pcb.pcb_cr3 = vtophys(pmap->pm_pdir));
}
vm_offset_t
pmap_addr_hint(vm_object_t obj, vm_offset_t addr, vm_size_t size)
{
if ((obj == NULL) || (size < NBPDR) || (obj->type != OBJT_DEVICE)) {
return addr;
}
addr = (addr + (NBPDR - 1)) & ~(NBPDR - 1);
return addr;
}
#if defined(PMAP_DEBUG)
pmap_pid_dump(int pid)
{
pmap_t pmap;
struct proc *p;
int npte = 0;
int index;
sx_slock(&allproc_lock);
LIST_FOREACH(p, &allproc, p_list) {
if (p->p_pid != pid)
continue;
if (p->p_vmspace) {
int i,j;
index = 0;
pmap = vmspace_pmap(p->p_vmspace);
for(i=0;i<1024;i++) {
pd_entry_t *pde;
unsigned *pte;
unsigned base = i << PDRSHIFT;
pde = &pmap->pm_pdir[i];
if (pde && pmap_pde_v(pde)) {
for(j=0;j<1024;j++) {
unsigned va = base + (j << PAGE_SHIFT);
if (va >= (vm_offset_t) VM_MIN_KERNEL_ADDRESS) {
if (index) {
index = 0;
printf("\n");
}
sx_sunlock(&allproc_lock);
return npte;
}
pte = pmap_pte_quick( pmap, va);
if (pte && pmap_pte_v(pte)) {
vm_offset_t pa;
vm_page_t m;
pa = *(int *)pte;
m = PHYS_TO_VM_PAGE(pa);
printf("va: 0x%x, pt: 0x%x, h: %d, w: %d, f: 0x%x",
va, pa, m->hold_count, m->wire_count, m->flags);
npte++;
index++;
if (index >= 2) {
index = 0;
printf("\n");
} else {
printf(" ");
}
}
}
}
}
}
}
sx_sunlock(&allproc_lock);
return npte;
}
#endif
#if defined(DEBUG)
static void pads __P((pmap_t pm));
void pmap_pvdump __P((vm_offset_t pa));
/* print address space of pmap*/
static void
pads(pm)
pmap_t pm;
{
unsigned va, i, j;
unsigned *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 << PDRSHIFT) + (j << PAGE_SHIFT);
if (pm == kernel_pmap && va < KERNBASE)
continue;
if (pm != kernel_pmap && va > UPT_MAX_ADDRESS)
continue;
ptep = pmap_pte_quick(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;
vm_page_t m;
printf("pa %x", pa);
m = PHYS_TO_VM_PAGE(pa);
for (pv = TAILQ_FIRST(&m->md.pv_list);
pv;
pv = TAILQ_NEXT(pv, pv_list)) {
#ifdef used_to_be
printf(" -> pmap %p, va %x, flags %x",
(void *)pv->pv_pmap, pv->pv_va, pv->pv_flags);
#endif
printf(" -> pmap %p, va %x", (void *)pv->pv_pmap, pv->pv_va);
pads(pv->pv_pmap);
}
printf(" ");
}
#endif
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