freebsd-dev/sys/vm/vm_page.c
David Greenman c3cb3e12f5 Moved some zero-initialized variables into .bss. Made code intended to be
called only from DDB #ifdef DDB. Removed some completely unused globals.
1995-04-16 12:56:22 +00:00

1176 lines
26 KiB
C

/*
* Copyright (c) 1991 Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The Mach Operating System project at Carnegie-Mellon University.
*
* 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: @(#)vm_page.c 7.4 (Berkeley) 5/7/91
* $Id: vm_page.c,v 1.30 1995/04/16 11:50:45 davidg Exp $
*/
/*
* Copyright (c) 1987, 1990 Carnegie-Mellon University.
* All rights reserved.
*
* Authors: Avadis Tevanian, Jr., Michael Wayne Young
*
* Permission to use, copy, modify and distribute this software and
* its documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
* FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie the
* rights to redistribute these changes.
*/
/*
* Resident memory management module.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_pageout.h>
/*
* Associated with page of user-allocatable memory is a
* page structure.
*/
struct pglist *vm_page_buckets; /* Array of buckets */
int vm_page_bucket_count; /* How big is array? */
int vm_page_hash_mask; /* Mask for hash function */
simple_lock_data_t bucket_lock; /* lock for all buckets XXX */
struct pglist vm_page_queue_free;
struct pglist vm_page_queue_active;
struct pglist vm_page_queue_inactive;
struct pglist vm_page_queue_cache;
simple_lock_data_t vm_page_queue_lock;
simple_lock_data_t vm_page_queue_free_lock;
/* has physical page allocation been initialized? */
boolean_t vm_page_startup_initialized;
vm_page_t vm_page_array;
int vm_page_array_size;
long first_page;
long last_page;
vm_offset_t first_phys_addr;
vm_offset_t last_phys_addr;
vm_size_t page_mask;
int page_shift;
/*
* map of contiguous valid DEV_BSIZE chunks in a page
* (this list is valid for page sizes upto 16*DEV_BSIZE)
*/
static u_short vm_page_dev_bsize_chunks[] = {
0x0, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff,
0x1ff, 0x3ff, 0x7ff, 0xfff, 0x1fff, 0x3fff, 0x7fff, 0xffff
};
/*
* vm_set_page_size:
*
* Sets the page size, perhaps based upon the memory
* size. Must be called before any use of page-size
* dependent functions.
*
* Sets page_shift and page_mask from cnt.v_page_size.
*/
void
vm_set_page_size()
{
if (cnt.v_page_size == 0)
cnt.v_page_size = DEFAULT_PAGE_SIZE;
page_mask = cnt.v_page_size - 1;
if ((page_mask & cnt.v_page_size) != 0)
panic("vm_set_page_size: page size not a power of two");
for (page_shift = 0;; page_shift++)
if ((1 << page_shift) == cnt.v_page_size)
break;
}
/*
* vm_page_startup:
*
* Initializes the resident memory module.
*
* Allocates memory for the page cells, and
* for the object/offset-to-page hash table headers.
* Each page cell is initialized and placed on the free list.
*/
vm_offset_t
vm_page_startup(starta, enda, vaddr)
register vm_offset_t starta;
vm_offset_t enda;
register vm_offset_t vaddr;
{
register vm_offset_t mapped;
register vm_page_t m;
register struct pglist *bucket;
vm_size_t npages, page_range;
register vm_offset_t new_start;
int i;
vm_offset_t pa;
int nblocks;
vm_offset_t first_managed_page;
/* the biggest memory array is the second group of pages */
vm_offset_t start;
vm_offset_t biggestone, biggestsize;
vm_offset_t total;
total = 0;
biggestsize = 0;
biggestone = 0;
nblocks = 0;
vaddr = round_page(vaddr);
for (i = 0; phys_avail[i + 1]; i += 2) {
phys_avail[i] = round_page(phys_avail[i]);
phys_avail[i + 1] = trunc_page(phys_avail[i + 1]);
}
for (i = 0; phys_avail[i + 1]; i += 2) {
int size = phys_avail[i + 1] - phys_avail[i];
if (size > biggestsize) {
biggestone = i;
biggestsize = size;
}
++nblocks;
total += size;
}
start = phys_avail[biggestone];
/*
* Initialize the locks
*/
simple_lock_init(&vm_page_queue_free_lock);
simple_lock_init(&vm_page_queue_lock);
/*
* Initialize the queue headers for the free queue, the active queue
* and the inactive queue.
*/
TAILQ_INIT(&vm_page_queue_free);
TAILQ_INIT(&vm_page_queue_active);
TAILQ_INIT(&vm_page_queue_inactive);
TAILQ_INIT(&vm_page_queue_cache);
/*
* Allocate (and initialize) the hash table buckets.
*
* The number of buckets MUST BE a power of 2, and the actual value is
* the next power of 2 greater than the number of physical pages in
* the system.
*
* Note: This computation can be tweaked if desired.
*/
vm_page_buckets = (struct pglist *) vaddr;
bucket = vm_page_buckets;
if (vm_page_bucket_count == 0) {
vm_page_bucket_count = 1;
while (vm_page_bucket_count < atop(total))
vm_page_bucket_count <<= 1;
}
vm_page_hash_mask = vm_page_bucket_count - 1;
/*
* Validate these addresses.
*/
new_start = start + vm_page_bucket_count * sizeof(struct pglist);
new_start = round_page(new_start);
mapped = vaddr;
vaddr = pmap_map(mapped, start, new_start,
VM_PROT_READ | VM_PROT_WRITE);
start = new_start;
bzero((caddr_t) mapped, vaddr - mapped);
mapped = vaddr;
for (i = 0; i < vm_page_bucket_count; i++) {
TAILQ_INIT(bucket);
bucket++;
}
simple_lock_init(&bucket_lock);
/*
* round (or truncate) the addresses to our page size.
*/
/*
* Pre-allocate maps and map entries that cannot be dynamically
* allocated via malloc(). The maps include the kernel_map and
* kmem_map which must be initialized before malloc() will work
* (obviously). Also could include pager maps which would be
* allocated before kmeminit.
*
* Allow some kernel map entries... this should be plenty since people
* shouldn't be cluttering up the kernel map (they should use their
* own maps).
*/
kentry_data_size = MAX_KMAP * sizeof(struct vm_map) +
MAX_KMAPENT * sizeof(struct vm_map_entry);
kentry_data_size = round_page(kentry_data_size);
kentry_data = (vm_offset_t) vaddr;
vaddr += kentry_data_size;
/*
* Validate these zone addresses.
*/
new_start = start + (vaddr - mapped);
pmap_map(mapped, start, new_start, VM_PROT_READ | VM_PROT_WRITE);
bzero((caddr_t) mapped, (vaddr - mapped));
start = round_page(new_start);
/*
* Compute the number of pages of memory that will be available for
* use (taking into account the overhead of a page structure per
* page).
*/
first_page = phys_avail[0] / PAGE_SIZE;
/* for VM_PAGE_CHECK() */
last_page = phys_avail[(nblocks - 1) * 2 + 1] / PAGE_SIZE;
page_range = last_page - (phys_avail[0] / PAGE_SIZE);
npages = (total - (page_range * sizeof(struct vm_page)) -
(start - phys_avail[biggestone])) / PAGE_SIZE;
/*
* Initialize the mem entry structures now, and put them in the free
* queue.
*/
vm_page_array = (vm_page_t) vaddr;
mapped = vaddr;
/*
* Validate these addresses.
*/
new_start = round_page(start + page_range * sizeof(struct vm_page));
mapped = pmap_map(mapped, start, new_start,
VM_PROT_READ | VM_PROT_WRITE);
start = new_start;
first_managed_page = start / PAGE_SIZE;
/*
* Clear all of the page structures
*/
bzero((caddr_t) vm_page_array, page_range * sizeof(struct vm_page));
vm_page_array_size = page_range;
cnt.v_page_count = 0;
cnt.v_free_count = 0;
for (i = 0; phys_avail[i + 1] && npages > 0; i += 2) {
if (i == biggestone)
pa = ptoa(first_managed_page);
else
pa = phys_avail[i];
while (pa < phys_avail[i + 1] && npages-- > 0) {
++cnt.v_page_count;
++cnt.v_free_count;
m = PHYS_TO_VM_PAGE(pa);
m->flags = PG_FREE;
m->phys_addr = pa;
TAILQ_INSERT_TAIL(&vm_page_queue_free, m, pageq);
pa += PAGE_SIZE;
}
}
/*
* Initialize vm_pages_needed lock here - don't wait for pageout
* daemon XXX
*/
simple_lock_init(&vm_pages_needed_lock);
return (mapped);
}
/*
* vm_page_hash:
*
* Distributes the object/offset key pair among hash buckets.
*
* NOTE: This macro depends on vm_page_bucket_count being a power of 2.
*/
inline const int
vm_page_hash(object, offset)
vm_object_t object;
vm_offset_t offset;
{
return ((unsigned) object + offset / NBPG) & vm_page_hash_mask;
}
/*
* vm_page_insert: [ internal use only ]
*
* Inserts the given mem entry into the object/object-page
* table and object list.
*
* The object and page must be locked, and must be splhigh.
*/
inline void
vm_page_insert(mem, object, offset)
register vm_page_t mem;
register vm_object_t object;
register vm_offset_t offset;
{
register struct pglist *bucket;
VM_PAGE_CHECK(mem);
if (mem->flags & PG_TABLED)
panic("vm_page_insert: already inserted");
/*
* Record the object/offset pair in this page
*/
mem->object = object;
mem->offset = offset;
/*
* Insert it into the object_object/offset hash table
*/
bucket = &vm_page_buckets[vm_page_hash(object, offset)];
simple_lock(&bucket_lock);
TAILQ_INSERT_TAIL(bucket, mem, hashq);
simple_unlock(&bucket_lock);
/*
* Now link into the object's list of backed pages.
*/
TAILQ_INSERT_TAIL(&object->memq, mem, listq);
mem->flags |= PG_TABLED;
/*
* And show that the object has one more resident page.
*/
object->resident_page_count++;
}
/*
* vm_page_remove: [ internal use only ]
* NOTE: used by device pager as well -wfj
*
* Removes the given mem entry from the object/offset-page
* table and the object page list.
*
* The object and page must be locked, and at splhigh.
*/
inline void
vm_page_remove(mem)
register vm_page_t mem;
{
register struct pglist *bucket;
VM_PAGE_CHECK(mem);
if (!(mem->flags & PG_TABLED))
return;
/*
* Remove from the object_object/offset hash table
*/
bucket = &vm_page_buckets[vm_page_hash(mem->object, mem->offset)];
simple_lock(&bucket_lock);
TAILQ_REMOVE(bucket, mem, hashq);
simple_unlock(&bucket_lock);
/*
* Now remove from the object's list of backed pages.
*/
TAILQ_REMOVE(&mem->object->memq, mem, listq);
/*
* And show that the object has one fewer resident page.
*/
mem->object->resident_page_count--;
mem->flags &= ~PG_TABLED;
}
/*
* vm_page_lookup:
*
* Returns the page associated with the object/offset
* pair specified; if none is found, NULL is returned.
*
* The object must be locked. No side effects.
*/
vm_page_t
vm_page_lookup(object, offset)
register vm_object_t object;
register vm_offset_t offset;
{
register vm_page_t mem;
register struct pglist *bucket;
int s;
/*
* Search the hash table for this object/offset pair
*/
bucket = &vm_page_buckets[vm_page_hash(object, offset)];
s = splhigh();
simple_lock(&bucket_lock);
for (mem = bucket->tqh_first; mem != NULL; mem = mem->hashq.tqe_next) {
VM_PAGE_CHECK(mem);
if ((mem->object == object) && (mem->offset == offset)) {
simple_unlock(&bucket_lock);
splx(s);
return (mem);
}
}
simple_unlock(&bucket_lock);
splx(s);
return (NULL);
}
/*
* vm_page_rename:
*
* Move the given memory entry from its
* current object to the specified target object/offset.
*
* The object must be locked.
*/
void
vm_page_rename(mem, new_object, new_offset)
register vm_page_t mem;
register vm_object_t new_object;
vm_offset_t new_offset;
{
int s;
if (mem->object == new_object)
return;
vm_page_lock_queues(); /* keep page from moving out from under pageout daemon */
s = splhigh();
vm_page_remove(mem);
vm_page_insert(mem, new_object, new_offset);
splx(s);
vm_page_unlock_queues();
}
/*
* vm_page_unqueue must be called at splhigh();
*/
inline void
vm_page_unqueue(vm_page_t mem)
{
int origflags;
origflags = mem->flags;
if ((origflags & (PG_ACTIVE|PG_INACTIVE|PG_CACHE)) == 0)
return;
if (origflags & PG_ACTIVE) {
TAILQ_REMOVE(&vm_page_queue_active, mem, pageq);
cnt.v_active_count--;
mem->flags &= ~PG_ACTIVE;
} else if (origflags & PG_INACTIVE) {
TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq);
cnt.v_inactive_count--;
mem->flags &= ~PG_INACTIVE;
} else if (origflags & PG_CACHE) {
TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq);
cnt.v_cache_count--;
mem->flags &= ~PG_CACHE;
if (cnt.v_cache_count + cnt.v_free_count < cnt.v_free_reserved)
pagedaemon_wakeup();
}
return;
}
/*
* vm_page_alloc:
*
* Allocate and return a memory cell associated
* with this VM object/offset pair.
*
* page_req classes:
* VM_ALLOC_NORMAL normal process request
* VM_ALLOC_SYSTEM system *really* needs a page
* VM_ALLOC_INTERRUPT interrupt time request
*
* Object must be locked.
*/
vm_page_t
vm_page_alloc(object, offset, page_req)
vm_object_t object;
vm_offset_t offset;
int page_req;
{
register vm_page_t mem;
int s;
if ((curproc == pageproc) && (page_req != VM_ALLOC_INTERRUPT)) {
page_req = VM_ALLOC_SYSTEM;
};
simple_lock(&vm_page_queue_free_lock);
s = splhigh();
mem = vm_page_queue_free.tqh_first;
switch (page_req) {
case VM_ALLOC_NORMAL:
if (cnt.v_free_count >= cnt.v_free_reserved) {
TAILQ_REMOVE(&vm_page_queue_free, mem, pageq);
cnt.v_free_count--;
} else {
mem = vm_page_queue_cache.tqh_first;
if (mem != NULL) {
TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq);
vm_page_remove(mem);
cnt.v_cache_count--;
} else {
simple_unlock(&vm_page_queue_free_lock);
splx(s);
pagedaemon_wakeup();
return (NULL);
}
}
break;
case VM_ALLOC_SYSTEM:
if ((cnt.v_free_count >= cnt.v_free_reserved) ||
((cnt.v_cache_count == 0) &&
(cnt.v_free_count >= cnt.v_interrupt_free_min))) {
TAILQ_REMOVE(&vm_page_queue_free, mem, pageq);
cnt.v_free_count--;
} else {
mem = vm_page_queue_cache.tqh_first;
if (mem != NULL) {
TAILQ_REMOVE(&vm_page_queue_cache, mem, pageq);
vm_page_remove(mem);
cnt.v_cache_count--;
} else {
simple_unlock(&vm_page_queue_free_lock);
splx(s);
pagedaemon_wakeup();
return (NULL);
}
}
break;
case VM_ALLOC_INTERRUPT:
if (mem != NULL) {
TAILQ_REMOVE(&vm_page_queue_free, mem, pageq);
cnt.v_free_count--;
} else {
simple_unlock(&vm_page_queue_free_lock);
splx(s);
pagedaemon_wakeup();
return NULL;
}
break;
default:
panic("vm_page_alloc: invalid allocation class");
}
simple_unlock(&vm_page_queue_free_lock);
mem->flags = PG_BUSY;
mem->wire_count = 0;
mem->hold_count = 0;
mem->act_count = 0;
mem->busy = 0;
mem->valid = 0;
mem->dirty = 0;
mem->bmapped = 0;
/* XXX before splx until vm_page_insert is safe */
vm_page_insert(mem, object, offset);
splx(s);
/*
* Don't wakeup too often - wakeup the pageout daemon when
* we would be nearly out of memory.
*/
if (((cnt.v_free_count + cnt.v_cache_count) < cnt.v_free_min) ||
(cnt.v_free_count < cnt.v_pageout_free_min))
pagedaemon_wakeup();
return (mem);
}
vm_offset_t
vm_page_alloc_contig(size, low, high, alignment)
vm_offset_t size;
vm_offset_t low;
vm_offset_t high;
vm_offset_t alignment;
{
int i, s, start;
vm_offset_t addr, phys, tmp_addr;
vm_page_t pga = vm_page_array;
if ((alignment & (alignment - 1)) != 0)
panic("vm_page_alloc_contig: alignment must be a power of 2");
start = 0;
s = splhigh();
again:
/*
* Find first page in array that is free, within range, and aligned.
*/
for (i = start; i < cnt.v_page_count; i++) {
phys = VM_PAGE_TO_PHYS(&pga[i]);
if (((pga[i].flags & PG_FREE) == PG_FREE) &&
(phys >= low) && (phys < high) &&
((phys & (alignment - 1)) == 0))
break;
}
/*
* If the above failed or we will exceed the upper bound, fail.
*/
if ((i == cnt.v_page_count) || ((VM_PAGE_TO_PHYS(&pga[i]) + size) > high)) {
splx(s);
return (NULL);
}
start = i;
/*
* Check successive pages for contiguous and free.
*/
for (i = start + 1; i < (start + size / PAGE_SIZE); i++) {
if ((VM_PAGE_TO_PHYS(&pga[i]) !=
(VM_PAGE_TO_PHYS(&pga[i - 1]) + PAGE_SIZE)) ||
((pga[i].flags & PG_FREE) != PG_FREE)) {
start++;
goto again;
}
}
/*
* We've found a contiguous chunk that meets are requirements.
* Allocate kernel VM, unfree and assign the physical pages to it and
* return kernel VM pointer.
*/
tmp_addr = addr = kmem_alloc_pageable(kernel_map, size);
for (i = start; i < (start + size / PAGE_SIZE); i++) {
vm_page_t m = &pga[i];
TAILQ_REMOVE(&vm_page_queue_free, m, pageq);
cnt.v_free_count--;
m->valid = VM_PAGE_BITS_ALL;
m->flags = 0;
m->dirty = 0;
m->wire_count = 0;
m->act_count = 0;
m->bmapped = 0;
m->busy = 0;
vm_page_insert(m, kernel_object, tmp_addr - VM_MIN_KERNEL_ADDRESS);
vm_page_wire(m);
pmap_kenter(tmp_addr, VM_PAGE_TO_PHYS(m));
tmp_addr += PAGE_SIZE;
}
splx(s);
return (addr);
}
/*
* vm_page_free:
*
* Returns the given page to the free list,
* disassociating it with any VM object.
*
* Object and page must be locked prior to entry.
*/
void
vm_page_free(mem)
register vm_page_t mem;
{
int s;
int flags;
s = splhigh();
vm_page_remove(mem);
vm_page_unqueue(mem);
flags = mem->flags;
if (mem->bmapped || mem->busy || flags & (PG_BUSY|PG_FREE)) {
if (flags & PG_FREE)
panic("vm_page_free: freeing free page");
printf("vm_page_free: offset(%d), bmapped(%d), busy(%d), PG_BUSY(%d)\n",
mem->offset, mem->bmapped, mem->busy, (flags & PG_BUSY) ? 1 : 0);
panic("vm_page_free: freeing busy page");
}
if ((flags & PG_WANTED) != 0)
wakeup((caddr_t) mem);
if ((flags & PG_FICTITIOUS) == 0) {
simple_lock(&vm_page_queue_free_lock);
if (mem->wire_count) {
if (mem->wire_count > 1) {
printf("vm_page_free: wire count > 1 (%d)", mem->wire_count);
panic("vm_page_free: invalid wire count");
}
cnt.v_wire_count--;
mem->wire_count = 0;
}
mem->flags |= PG_FREE;
TAILQ_INSERT_TAIL(&vm_page_queue_free, mem, pageq);
simple_unlock(&vm_page_queue_free_lock);
splx(s);
/*
* if pageout daemon needs pages, then tell it that there are
* some free.
*/
if (vm_pageout_pages_needed) {
wakeup((caddr_t) &vm_pageout_pages_needed);
vm_pageout_pages_needed = 0;
}
cnt.v_free_count++;
/*
* wakeup processes that are waiting on memory if we hit a
* high water mark. And wakeup scheduler process if we have
* lots of memory. this process will swapin processes.
*/
if ((cnt.v_free_count + cnt.v_cache_count) == cnt.v_free_min) {
wakeup((caddr_t) &cnt.v_free_count);
wakeup((caddr_t) &proc0);
}
} else {
splx(s);
}
cnt.v_tfree++;
}
/*
* vm_page_wire:
*
* Mark this page as wired down by yet
* another map, removing it from paging queues
* as necessary.
*
* The page queues must be locked.
*/
void
vm_page_wire(mem)
register vm_page_t mem;
{
int s;
VM_PAGE_CHECK(mem);
if (mem->wire_count == 0) {
s = splhigh();
vm_page_unqueue(mem);
splx(s);
cnt.v_wire_count++;
}
mem->flags |= PG_WRITEABLE|PG_MAPPED;
mem->wire_count++;
}
/*
* vm_page_unwire:
*
* Release one wiring of this page, potentially
* enabling it to be paged again.
*
* The page queues must be locked.
*/
void
vm_page_unwire(mem)
register vm_page_t mem;
{
int s;
VM_PAGE_CHECK(mem);
s = splhigh();
if (mem->wire_count)
mem->wire_count--;
if (mem->wire_count == 0) {
TAILQ_INSERT_TAIL(&vm_page_queue_active, mem, pageq);
cnt.v_active_count++;
mem->flags |= PG_ACTIVE;
cnt.v_wire_count--;
}
splx(s);
}
/*
* vm_page_activate:
*
* Put the specified page on the active list (if appropriate).
*
* The page queues must be locked.
*/
void
vm_page_activate(m)
register vm_page_t m;
{
int s;
VM_PAGE_CHECK(m);
s = splhigh();
if (m->flags & PG_ACTIVE)
panic("vm_page_activate: already active");
if (m->flags & PG_CACHE)
cnt.v_reactivated++;
vm_page_unqueue(m);
if (m->wire_count == 0) {
TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq);
m->flags |= PG_ACTIVE;
if (m->act_count < 5)
m->act_count = 5;
else if( m->act_count < ACT_MAX)
m->act_count += 1;
cnt.v_active_count++;
}
splx(s);
}
/*
* vm_page_deactivate:
*
* Returns the given page to the inactive list,
* indicating that no physical maps have access
* to this page. [Used by the physical mapping system.]
*
* The page queues must be locked.
*/
void
vm_page_deactivate(m)
register vm_page_t m;
{
int spl;
VM_PAGE_CHECK(m);
/*
* Only move active pages -- ignore locked or already inactive ones.
*
* XXX: sometimes we get pages which aren't wired down or on any queue -
* we need to put them on the inactive queue also, otherwise we lose
* track of them. Paul Mackerras (paulus@cs.anu.edu.au) 9-Jan-93.
*/
spl = splhigh();
if (!(m->flags & PG_INACTIVE) && m->wire_count == 0 &&
m->hold_count == 0) {
pmap_clear_reference(VM_PAGE_TO_PHYS(m));
if (m->flags & PG_CACHE)
cnt.v_reactivated++;
vm_page_unqueue(m);
TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq);
m->flags |= PG_INACTIVE;
cnt.v_inactive_count++;
m->act_count = 0;
}
splx(spl);
}
/*
* vm_page_cache
*
* Put the specified page onto the page cache queue (if appropriate).
*/
void
vm_page_cache(m)
register vm_page_t m;
{
int s;
VM_PAGE_CHECK(m);
if ((m->flags & (PG_CACHE | PG_BUSY)) || m->busy || m->wire_count ||
m->bmapped)
return;
s = splhigh();
vm_page_unqueue(m);
vm_page_protect(m, VM_PROT_NONE);
TAILQ_INSERT_TAIL(&vm_page_queue_cache, m, pageq);
m->flags |= PG_CACHE;
cnt.v_cache_count++;
if ((cnt.v_free_count + cnt.v_cache_count) == cnt.v_free_min) {
wakeup((caddr_t) &cnt.v_free_count);
wakeup((caddr_t) &proc0);
}
if (vm_pageout_pages_needed) {
wakeup((caddr_t) &vm_pageout_pages_needed);
vm_pageout_pages_needed = 0;
}
splx(s);
}
/*
* vm_page_zero_fill:
*
* Zero-fill the specified page.
* Written as a standard pagein routine, to
* be used by the zero-fill object.
*/
boolean_t
vm_page_zero_fill(m)
vm_page_t m;
{
VM_PAGE_CHECK(m);
pmap_zero_page(VM_PAGE_TO_PHYS(m));
m->valid = VM_PAGE_BITS_ALL;
return (TRUE);
}
/*
* vm_page_copy:
*
* Copy one page to another
*/
void
vm_page_copy(src_m, dest_m)
vm_page_t src_m;
vm_page_t dest_m;
{
VM_PAGE_CHECK(src_m);
VM_PAGE_CHECK(dest_m);
pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m));
dest_m->valid = VM_PAGE_BITS_ALL;
}
/*
* mapping function for valid bits or for dirty bits in
* a page
*/
inline int
vm_page_bits(int base, int size)
{
u_short chunk;
if ((base == 0) && (size >= PAGE_SIZE))
return VM_PAGE_BITS_ALL;
size = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1);
base = (base % PAGE_SIZE) / DEV_BSIZE;
chunk = vm_page_dev_bsize_chunks[size / DEV_BSIZE];
return (chunk << base) & VM_PAGE_BITS_ALL;
}
/*
* set a page (partially) valid
*/
void
vm_page_set_valid(m, base, size)
vm_page_t m;
int base;
int size;
{
m->valid |= vm_page_bits(base, size);
}
/*
* set a page (partially) invalid
*/
void
vm_page_set_invalid(m, base, size)
vm_page_t m;
int base;
int size;
{
int bits;
m->valid &= ~(bits = vm_page_bits(base, size));
if (m->valid == 0)
m->dirty &= ~bits;
}
/*
* is (partial) page valid?
*/
int
vm_page_is_valid(m, base, size)
vm_page_t m;
int base;
int size;
{
int bits = vm_page_bits(base, size);
if (m->valid && ((m->valid & bits) == bits))
return 1;
else
return 0;
}
/*
* set a page (partially) dirty
*/
void
vm_page_set_dirty(m, base, size)
vm_page_t m;
int base;
int size;
{
if ((base != 0) || (size != PAGE_SIZE)) {
if (pmap_is_modified(VM_PAGE_TO_PHYS(m))) {
m->dirty = VM_PAGE_BITS_ALL;
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
return;
}
m->dirty |= vm_page_bits(base, size);
} else {
m->dirty = VM_PAGE_BITS_ALL;
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
}
}
void
vm_page_test_dirty(m)
vm_page_t m;
{
if ((m->dirty != VM_PAGE_BITS_ALL) &&
pmap_is_modified(VM_PAGE_TO_PHYS(m))) {
m->dirty = VM_PAGE_BITS_ALL;
}
}
/*
* set a page (partially) clean
*/
void
vm_page_set_clean(m, base, size)
vm_page_t m;
int base;
int size;
{
m->dirty &= ~vm_page_bits(base, size);
if( base == 0 && size == PAGE_SIZE)
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
}
/*
* is (partial) page clean
*/
int
vm_page_is_clean(m, base, size)
vm_page_t m;
int base;
int size;
{
if (pmap_is_modified(VM_PAGE_TO_PHYS(m))) {
m->dirty = VM_PAGE_BITS_ALL;
pmap_clear_modify(VM_PAGE_TO_PHYS(m));
}
if ((m->dirty & m->valid & vm_page_bits(base, size)) == 0)
return 1;
else
return 0;
}
#ifdef DDB
void
print_page_info()
{
printf("cnt.v_free_count: %d\n", cnt.v_free_count);
printf("cnt.v_cache_count: %d\n", cnt.v_cache_count);
printf("cnt.v_inactive_count: %d\n", cnt.v_inactive_count);
printf("cnt.v_active_count: %d\n", cnt.v_active_count);
printf("cnt.v_wire_count: %d\n", cnt.v_wire_count);
printf("cnt.v_free_reserved: %d\n", cnt.v_free_reserved);
printf("cnt.v_free_min: %d\n", cnt.v_free_min);
printf("cnt.v_free_target: %d\n", cnt.v_free_target);
printf("cnt.v_cache_min: %d\n", cnt.v_cache_min);
printf("cnt.v_inactive_target: %d\n", cnt.v_inactive_target);
}
#endif