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NetBSD/sys/vm/vm_page.c

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/* $NetBSD: vm_page.c,v 1.48 1999/01/16 20:00:28 chuck Exp $ */
#define VM_PAGE_ALLOC_MEMORY_STATS
/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
* NASA Ames Research Center.
*
* 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 NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
/*
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* The 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.
*
* @(#)vm_page.c 8.4 (Berkeley) 1/9/95
*
*
* 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 <sys/malloc.h>
#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_map.h>
#include <vm/vm_pageout.h>
#include <machine/cpu.h>
#define VERY_LOW_MEM() (cnt.v_free_count <= vm_page_free_reserved)
#define KERN_OBJ(object) ((object) == kernel_object || (object) == kmem_object)
int vm_page_free_reserved = 10;
/*
* physical memory config is stored in vm_physmem.
*/
struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
int vm_nphysseg = 0;
static int vm_page_lost_count = 0; /* XXXCDC: DEBUG DEBUG */
/*
* These variables record the values returned by vm_page_bootstrap,
* for debugging purposes.
*
* The implementation of vm_bootstrap_steal_memory here also uses
* them internally.
*/
static vaddr_t virtual_space_start;
static vaddr_t virtual_space_end;
vaddr_t vm_bootstrap_steal_memory __P((vsize_t));
/*
* Associated with page of user-allocatable memory is a
* page structure.
*/
struct pglist *vm_page_buckets; /* Array of buckets */
int vm_page_bucket_count = 0; /* 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_bootbucket; /* bootstrap bucket */
struct pglist vm_page_queue_free;
struct pglist vm_page_queue_active;
struct pglist vm_page_queue_inactive;
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;
vsize_t page_mask;
int page_shift;
/*
* local prototypes
*/
#if !defined(PMAP_STEAL_MEMORY)
static boolean_t vm_page_physget __P((paddr_t *));
#endif
/*
* macros
*/
/*
* 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.
*/
#define vm_page_hash(object, offset) \
(((unsigned long)object+(unsigned long)atop(offset))&vm_page_hash_mask)
/*
* 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_bootstrap: initialize the resident memory module (called
* from vm_mem_init()).
*
* - startp and endp are out params which return the boundaries of the
* free part of the kernel's virtual address space.
*/
void
vm_page_bootstrap(startp, endp)
vaddr_t *startp, *endp; /* OUT, OUT */
{
paddr_t paddr;
vm_page_t pagearray;
int lcv, freepages, pagecount, n, i;
/*
* first init all the locks and queues.
*/
simple_lock_init(&vm_page_queue_free_lock);
simple_lock_init(&vm_page_queue_lock);
TAILQ_INIT(&vm_page_queue_free);
TAILQ_INIT(&vm_page_queue_active);
TAILQ_INIT(&vm_page_queue_inactive);
/*
* init the <OBJ,OFFSET> => <PAGE> hash table buckets. for now
* we just have one bucket (the bootstrap bucket). later on we
* will malloc() new buckets as we dynamically resize the hash table.
*/
vm_page_bucket_count = 1;
vm_page_hash_mask = 0;
vm_page_buckets = &vm_page_bootbucket;
TAILQ_INIT(vm_page_buckets);
simple_lock_init(&bucket_lock);
/*
* before calling this function the MD code is expected to register
* some free RAM with the vm_page_physload() function. our job
* now is to allocate vm_page structures for this preloaded memory.
*/
if (vm_nphysseg == 0)
panic("vm_page_bootstrap: no memory pre-allocated");
/*
* first calculate the number of free pages... note that start/end
* are inclusive so you have to add one to get the number of pages.
*
* note that we use start/end rather than avail_start/avail_end.
* this allows us to allocate extra vm_page structures in case we
* want to return some memory to the pool after booting.
*/
freepages = 0;
for (lcv = 0; lcv < vm_nphysseg; lcv++) {
freepages = freepages +
(vm_physmem[lcv].end - vm_physmem[lcv].start);
}
/*
* we now know we have (PAGE_SIZE * freepages) bytes of memory we can
* use. for each page of memory we use we need a vm_page structure.
* thus, the total number of pages we can use is the total size of
* the memory divided by the PAGE_SIZE plus the size of the vm_page
* structure. we add one to freepages as a fudge factor to avoid
* truncation errors (since we can only allocate in terms of whole
* pages).
*/
pagecount = (PAGE_SIZE * (freepages + 1)) /
(PAGE_SIZE + sizeof(struct vm_page));
pagearray = (vm_page_t)
vm_bootstrap_steal_memory(pagecount * sizeof(struct vm_page));
memset(pagearray, 0, pagecount * sizeof(struct vm_page));
/*
* now init the page frames
*/
for (lcv = 0; lcv < vm_nphysseg; lcv++) {
n = vm_physmem[lcv].end - vm_physmem[lcv].start;
if (n > pagecount) {
printf("vm_init: lost %d page(s) in init\n",
n - pagecount);
vm_page_lost_count += (n - pagecount);
n = pagecount;
}
/* set up page array pointers */
vm_physmem[lcv].pgs = pagearray;
pagearray += n;
pagecount -= n;
vm_physmem[lcv].lastpg = vm_physmem[lcv].pgs + (n - 1);
/* init and free vm_pages (we've already zeroed them) */
paddr = ptoa(vm_physmem[lcv].start);
for (i = 0; i < n; i++, paddr += PAGE_SIZE) {
vm_physmem[lcv].pgs[i].phys_addr = paddr;
if (atop(paddr) >= vm_physmem[lcv].avail_start &&
atop(paddr) <= vm_physmem[lcv].avail_end)
vm_page_free(&vm_physmem[lcv].pgs[i]);
}
}
/*
* pass up the values of virtual_space_start and virtual_space_end
* (obtained by vm_bootstrap_steal_memory) to the upper layers of
* the VM.
*/
*startp = round_page(virtual_space_start);
*endp = trunc_page(virtual_space_end);
/*
* init pagedaemon lock
*/
simple_lock_init(&vm_pages_needed_lock);
}
/*
* vm_bootstrap_steal_memory: steal memory from physmem for bootstrapping
*/
vaddr_t
vm_bootstrap_steal_memory(size)
vsize_t size;
{
#if defined(PMAP_STEAL_MEMORY)
vaddr_t addr;
/*
* Defer this to machine-dependent code; we may need to allocate
* from a direct-mapped segment.
*/
addr = pmap_steal_memory(size, &virtual_space_start,
&virtual_space_end);
/* round it the way we like it */
virtual_space_start = round_page(virtual_space_start);
virtual_space_end = trunc_page(virtual_space_end);
return (addr);
#else /* ! PMAP_STEAL_MEMORY */
vaddr_t addr, vaddr, paddr;
/* round to page size */
size = round_page(size);
/*
* on first call to this function init ourselves. we detect this
* by checking virtual_space_start/end which are in the zero'd BSS
* area.
*/
if (virtual_space_start == virtual_space_end) {
pmap_virtual_space(&virtual_space_start, &virtual_space_end);
/* round it the way we like it */
virtual_space_start = round_page(virtual_space_start);
virtual_space_end = trunc_page(virtual_space_end);
}
/*
* allocate virtual memory for this request
*/
addr = virtual_space_start;
virtual_space_start += size;
/*
* allocate and mapin physical pages to back new virtual pages
*/
for (vaddr = round_page(addr); vaddr < addr + size;
vaddr += PAGE_SIZE) {
if (!vm_page_physget(&paddr))
panic("vm_bootstrap_steal_memory: out of memory");
/* XXX: should be wired, but some pmaps don't like that ... */
pmap_enter(pmap_kernel(), vaddr, paddr,
VM_PROT_READ|VM_PROT_WRITE, FALSE);
}
return(addr);
#endif /* PMAP_STEAL_MEMORY */
}
#if !defined(PMAP_STEAL_MEMORY)
/*
* vm_page_physget: "steal" one page from the vm_physmem structure.
*
* - attempt to allocate it off the end of a segment in which the "avail"
* values match the start/end values. if we can't do that, then we
* will advance both values (making them equal, and removing some
* vm_page structures from the non-avail area).
* - return false if out of memory.
*/
static boolean_t
vm_page_physget(paddrp)
paddr_t *paddrp;
{
int lcv, x;
/* pass 1: try allocating from a matching end */
#if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
for (lcv = vm_nphysseg - 1 ; lcv >= 0 ; lcv--)
#else
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++)
#endif
{
if (vm_physmem[lcv].pgs)
panic("vm_page_physget: called _after_ bootstrap");
/* try from front */
if (vm_physmem[lcv].avail_start == vm_physmem[lcv].start &&
vm_physmem[lcv].avail_start < vm_physmem[lcv].avail_end) {
*paddrp = ptoa(vm_physmem[lcv].avail_start);
vm_physmem[lcv].avail_start++;
vm_physmem[lcv].start++;
/* nothing left? nuke it */
if (vm_physmem[lcv].avail_start ==
vm_physmem[lcv].end) {
if (vm_nphysseg == 1)
panic("vm_page_physget: out of memory!");
vm_nphysseg--;
for (x = lcv; x < vm_nphysseg; x++)
/* structure copy */
vm_physmem[x] = vm_physmem[x+1];
}
return(TRUE);
}
/* try from rear */
if (vm_physmem[lcv].avail_end == vm_physmem[lcv].end &&
vm_physmem[lcv].avail_start < vm_physmem[lcv].avail_end) {
*paddrp = ptoa(vm_physmem[lcv].avail_end - 1);
vm_physmem[lcv].avail_end--;
vm_physmem[lcv].end--;
/* nothing left? nuke it */
if (vm_physmem[lcv].avail_end ==
vm_physmem[lcv].start) {
if (vm_nphysseg == 1)
panic("vm_page_physget: out of memory!");
vm_nphysseg--;
for (x = lcv; x < vm_nphysseg; x++)
/* structure copy */
vm_physmem[x] = vm_physmem[x+1];
}
return(TRUE);
}
}
/* pass2: forget about matching ends, just allocate something */
#if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
for (lcv = vm_nphysseg - 1 ; lcv >= 0 ; lcv--)
#else
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++)
#endif
{
/* any room in this bank? */
if (vm_physmem[lcv].avail_start >= vm_physmem[lcv].avail_end)
continue; /* nope */
*paddrp = ptoa(vm_physmem[lcv].avail_start);
vm_physmem[lcv].avail_start++;
vm_physmem[lcv].start = vm_physmem[lcv].avail_start; /* truncate! */
/* nothing left? nuke it */
if (vm_physmem[lcv].avail_start == vm_physmem[lcv].end) {
if (vm_nphysseg == 1)
panic("vm_page_physget: out of memory!");
vm_nphysseg--;
for (x = lcv; x < vm_nphysseg; x++)
vm_physmem[x] = vm_physmem[x+1]; /* structure copy */
}
return(TRUE);
}
return(FALSE); /* whoops! */
}
#endif /* ! PMAP_STEAL_MEMORY */
/*
* vm_page_physload: load physical memory into VM system
*
* - all args are PFs
* - all pages in start/end get vm_page structures
* - areas marked by avail_start/avail_end get added to the free page pool
* - we are limited to VM_PHYSSEG_MAX physical memory segments
*/
void
vm_page_physload(start, end, avail_start, avail_end)
vaddr_t start, end, avail_start, avail_end;
{
struct vm_page *pgs;
struct vm_physseg *ps;
int preload, lcv, npages;
#if (VM_PHYSSEG_STRAT != VM_PSTRAT_RANDOM)
int x;
#endif
if (page_shift == 0)
panic("vm_page_physload: page size not set!");
/*
* do we have room?
*/
if (vm_nphysseg == VM_PHYSSEG_MAX) {
printf("vm_page_physload: unable to load physical memory segment\n");
printf("\t%d segments allocated, ignoring 0x%lx -> 0x%lx\n",
VM_PHYSSEG_MAX, start, end);
return;
}
/*
* check to see if this is a "preload" (i.e. vm_mem_init hasn't been
* called yet, so malloc is not available).
*/
for (lcv = 0; lcv < vm_nphysseg; lcv++) {
if (vm_physmem[lcv].pgs)
break;
}
preload = (lcv == vm_nphysseg);
/*
* if VM is already running, attempt to malloc() vm_page structures
*/
if (!preload) {
#if defined(VM_PHYSSEG_NOADD)
panic("vm_page_physload: tried to add RAM after vm_mem_init");
#else
/* XXXCDC: need some sort of lockout for this case */
paddr_t paddr;
/* # of pages */
npages = end - start;
MALLOC(pgs, struct vm_page *, sizeof(struct vm_page) * npages,
M_VMPAGE, M_NOWAIT);
if (pgs == NULL) {
printf("vm_page_physload: can not malloc vm_page structs for segment\n");
printf("\tignoring 0x%lx -> 0x%lx\n", start, end);
return;
}
/* zero data, init phys_addr, and free pages */
memset(pgs, 0, sizeof(struct vm_page) * npages);
for (lcv = 0, paddr = ptoa(start); lcv < npages;
lcv++, paddr += PAGE_SIZE) {
pgs[lcv].phys_addr = paddr;
if (atop(paddr) >= avail_start &&
atop(paddr) <= avail_end)
vm_page_free(&pgs[lcv]);
}
/* XXXCDC: incomplete: need to update v_free_count, what else? */
/* XXXCDC: need hook to tell pmap to rebuild pv_list, etc... */
#endif
} else {
/* XXX/gcc complains if these don't get init'd */
pgs = NULL;
npages = 0;
}
/*
* now insert us in the proper place in vm_physmem[]
*/
#if (VM_PHYSSEG_STRAT == VM_PSTRAT_RANDOM)
/* random: put it at the end (easy!) */
ps = &vm_physmem[vm_nphysseg];
#else
#if (VM_PHYSSEG_STRAT == VM_PSTRAT_BSEARCH)
/* sort by address for binary search */
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++)
if (start < vm_physmem[lcv].start)
break;
ps = &vm_physmem[lcv];
/* move back other entries, if necessary ... */
for (x = vm_nphysseg ; x > lcv ; x--)
/* structure copy */
vm_physmem[x] = vm_physmem[x - 1];
#else
#if (VM_PHYSSEG_STRAT == VM_PSTRAT_BIGFIRST)
/* sort by largest segment first */
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++)
if ((end - start) >
(vm_physmem[lcv].end - vm_physmem[lcv].start))
break;
ps = &vm_physmem[lcv];
/* move back other entries, if necessary ... */
for (x = vm_nphysseg ; x > lcv ; x--)
/* structure copy */
vm_physmem[x] = vm_physmem[x - 1];
#else
panic("vm_page_physload: unknown physseg strategy selected!");
#endif
#endif
#endif
ps->start = start;
ps->end = end;
ps->avail_start = avail_start;
ps->avail_end = avail_end;
if (preload) {
ps->pgs = NULL;
} else {
ps->pgs = pgs;
ps->lastpg = pgs + npages - 1;
}
vm_nphysseg++;
/*
* done!
*/
return;
}
/*
* vm_page_physrehash: reallocate hash table based on number of
* free pages.
*/
void
vm_page_physrehash()
{
struct pglist *newbuckets, *oldbuckets;
struct vm_page *pg;
int freepages, lcv, bucketcount, s, oldcount;
/*
* compute number of pages that can go in the free pool
*/
freepages = 0;
for (lcv = 0; lcv < vm_nphysseg; lcv++)
freepages = freepages + (vm_physmem[lcv].avail_end -
vm_physmem[lcv].avail_start);
/*
* compute number of buckets needed for this number of pages
*/
bucketcount = 1;
while (bucketcount < freepages)
bucketcount = bucketcount * 2;
/*
* malloc new buckets
*/
MALLOC(newbuckets, struct pglist *, sizeof(struct pglist) * bucketcount,
M_VMPBUCKET, M_NOWAIT);
if (newbuckets == NULL) {
printf("vm_page_physrehash: WARNING: could not grow page hash table\n");
return;
}
for (lcv = 0; lcv < bucketcount; lcv++)
TAILQ_INIT(&newbuckets[lcv]);
/*
* now replace the old buckets with the new ones and rehash everything
*/
s = splimp();
simple_lock(&bucket_lock);
/* swap old for new ... */
oldbuckets = vm_page_buckets;
oldcount = vm_page_bucket_count;
vm_page_buckets = newbuckets;
vm_page_bucket_count = bucketcount;
vm_page_hash_mask = bucketcount - 1; /* power of 2 */
/* ... and rehash */
for (lcv = 0 ; lcv < oldcount ; lcv++) {
while ((pg = oldbuckets[lcv].tqh_first) != NULL) {
TAILQ_REMOVE(&oldbuckets[lcv], pg, hashq);
TAILQ_INSERT_TAIL(&vm_page_buckets[
vm_page_hash(pg->object, pg->offset)], pg, hashq);
}
}
simple_unlock(&bucket_lock);
splx(s);
/*
* free old bucket array if we malloc'd it previously
*/
if (oldbuckets != &vm_page_bootbucket)
FREE(oldbuckets, M_VMPBUCKET);
/*
* done
*/
return;
}
#if 1 /* XXXCDC: TMP TMP TMP DEBUG DEBUG DEBUG */
void vm_page_physdump __P((void)); /* SHUT UP GCC */
/* call from DDB */
void
vm_page_physdump()
{
int lcv;
printf("rehash: physical memory config [segs=%d of %d]:\n",
vm_nphysseg, VM_PHYSSEG_MAX);
for (lcv = 0 ; lcv < vm_nphysseg ; lcv++)
printf("0x%lx->0x%lx [0x%lx->0x%lx]\n", vm_physmem[lcv].start,
vm_physmem[lcv].end, vm_physmem[lcv].avail_start,
vm_physmem[lcv].avail_end);
printf("STRATEGY = ");
switch (VM_PHYSSEG_STRAT) {
case VM_PSTRAT_RANDOM:
printf("RANDOM\n");
break;
case VM_PSTRAT_BSEARCH:
printf("BSEARCH\n");
break;
case VM_PSTRAT_BIGFIRST:
printf("BIGFIRST\n");
break;
default:
printf("<<UNKNOWN>>!!!!\n");
}
printf("number of buckets = %d\n", vm_page_bucket_count);
printf("number of lost pages = %d\n", vm_page_lost_count);
}
#endif
/*
* 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.
*/
void
vm_page_insert(mem, object, offset)
register vm_page_t mem;
register vm_object_t object;
register vaddr_t offset;
{
register struct pglist *bucket;
int spl;
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)];
spl = splimp();
simple_lock(&bucket_lock);
TAILQ_INSERT_TAIL(bucket, mem, hashq);
simple_unlock(&bucket_lock);
(void) splx(spl);
/*
* 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 ]
* XXX: used by device pager as well
*
* Removes the given mem entry from the object/offset-page
* table and the object page list.
*
* The object and page must be locked.
*/
void
vm_page_remove(mem)
register vm_page_t mem;
{
register struct pglist *bucket;
int spl;
VM_PAGE_CHECK(mem);
#ifdef DIAGNOSTIC
if (mem->flags & PG_FAULTING)
panic("vm_page_remove: page is faulting");
#endif
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)];
spl = splimp();
simple_lock(&bucket_lock);
TAILQ_REMOVE(bucket, mem, hashq);
simple_unlock(&bucket_lock);
(void) splx(spl);
/*
* 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 vaddr_t offset;
{
register vm_page_t mem;
register struct pglist *bucket;
int spl;
/*
* Search the hash table for this object/offset pair
*/
bucket = &vm_page_buckets[vm_page_hash(object, offset)];
spl = splimp();
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(spl);
return(mem);
}
}
simple_unlock(&bucket_lock);
splx(spl);
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;
vaddr_t new_offset;
{
if (mem->object == new_object)
return;
vm_page_lock_queues(); /* keep page from moving out from
under pageout daemon */
vm_page_remove(mem);
vm_page_insert(mem, new_object, new_offset);
vm_page_unlock_queues();
}
/*
* vm_page_alloc:
*
* Allocate and return a memory cell associated
* with this VM object/offset pair.
*
* Object must be locked.
*/
vm_page_t
vm_page_alloc(object, offset)
vm_object_t object;
vaddr_t offset;
{
register vm_page_t mem;
int spl;
spl = splimp(); /* XXX */
simple_lock(&vm_page_queue_free_lock);
mem = vm_page_queue_free.tqh_first;
if (VERY_LOW_MEM()) {
if ((!KERN_OBJ(object) && curproc != pageout_daemon)
|| mem == NULL) {
simple_unlock(&vm_page_queue_free_lock);
splx(spl);
return(NULL);
}
}
#ifdef DIAGNOSTIC
if (mem == NULL) /* because we now depend on VERY_LOW_MEM() */
panic("vm_page_alloc");
#endif
TAILQ_REMOVE(&vm_page_queue_free, mem, pageq);
cnt.v_free_count--;
simple_unlock(&vm_page_queue_free_lock);
splx(spl);
VM_PAGE_INIT(mem, object, offset);
/*
* Decide if we should poke the pageout daemon.
* We do this if the free count is less than the low
* water mark, or if the free count is less than the high
* water mark (but above the low water mark) and the inactive
* count is less than its target.
*
* We don't have the counts locked ... if they change a little,
* it doesn't really matter.
*/
if (cnt.v_free_count < cnt.v_free_min ||
(cnt.v_free_count < cnt.v_free_target &&
cnt.v_inactive_count < cnt.v_inactive_target))
thread_wakeup(&vm_pages_needed);
return (mem);
}
/*
* 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;
{
vm_page_remove(mem);
vm_page_free1(mem);
}
/*
* vm_page_alloc1:
*
* Allocate and return a memory cell with no associated object.
*/
vm_page_t
vm_page_alloc1()
{
vm_page_t mem;
int spl;
spl = splimp();
simple_lock(&vm_page_queue_free_lock);
if (vm_page_queue_free.tqh_first == NULL) {
simple_unlock(&vm_page_queue_free_lock);
splx(spl);
return (NULL);
}
mem = vm_page_queue_free.tqh_first;
TAILQ_REMOVE(&vm_page_queue_free, mem, pageq);
cnt.v_free_count--;
simple_unlock(&vm_page_queue_free_lock);
splx(spl);
mem->flags = PG_BUSY | PG_CLEAN | PG_FAKE;
mem->wire_count = 0;
/*
* Decide if we should poke the pageout daemon.
* We do this if the free count is less than the low
* water mark, or if the free count is less than the high
* water mark (but above the low water mark) and the inactive
* count is less than its target.
*
* We don't have the counts locked ... if they change a little,
* it doesn't really matter.
*/
if (cnt.v_free_count < cnt.v_free_min ||
(cnt.v_free_count < cnt.v_free_target &&
cnt.v_inactive_count < cnt.v_inactive_target))
thread_wakeup((void *)&vm_pages_needed);
return (mem);
}
/*
* vm_page_free1:
*
* Returns the given page to the free list.
*
* The page must already be disassociated with
* any objects.
*/
void
vm_page_free1(mem)
vm_page_t mem;
{
if (mem->flags & PG_ACTIVE) {
TAILQ_REMOVE(&vm_page_queue_active, mem, pageq);
mem->flags &= ~PG_ACTIVE;
cnt.v_active_count--;
}
if (mem->flags & PG_INACTIVE) {
TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq);
mem->flags &= ~PG_INACTIVE;
cnt.v_inactive_count--;
}
if (!(mem->flags & PG_FICTITIOUS)) {
int spl;
spl = splimp();
simple_lock(&vm_page_queue_free_lock);
mem->flags |= PG_FREE;
TAILQ_INSERT_TAIL(&vm_page_queue_free, mem, pageq);
cnt.v_free_count++;
simple_unlock(&vm_page_queue_free_lock);
splx(spl);
}
}
/*
* 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;
{
VM_PAGE_CHECK(mem);
if (mem->wire_count == 0) {
if (mem->flags & PG_ACTIVE) {
TAILQ_REMOVE(&vm_page_queue_active, mem, pageq);
cnt.v_active_count--;
mem->flags &= ~PG_ACTIVE;
}
if (mem->flags & PG_INACTIVE) {
TAILQ_REMOVE(&vm_page_queue_inactive, mem, pageq);
cnt.v_inactive_count--;
mem->flags &= ~PG_INACTIVE;
}
cnt.v_wire_count++;
}
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;
{
VM_PAGE_CHECK(mem);
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--;
}
}
/*
* 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;
{
VM_PAGE_CHECK(m);
/*
* Only move active pages -- ignore locked or already
* inactive ones.
*/
if (m->flags & PG_ACTIVE) {
TAILQ_REMOVE(&vm_page_queue_active, m, pageq);
m->flags &= ~PG_ACTIVE;
cnt.v_active_count--;
goto deact;
}
if ((m->flags & PG_INACTIVE) == 0) {
deact:
TAILQ_INSERT_TAIL(&vm_page_queue_inactive, m, pageq);
m->flags |= PG_INACTIVE;
cnt.v_inactive_count++;
pmap_clear_reference(VM_PAGE_TO_PHYS(m));
if (pmap_is_modified(VM_PAGE_TO_PHYS(m)))
m->flags &= ~PG_CLEAN;
if (m->flags & PG_CLEAN)
m->flags &= ~PG_LAUNDRY;
else
m->flags |= PG_LAUNDRY;
}
}
/*
* 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;
{
VM_PAGE_CHECK(m);
if (m->flags & PG_INACTIVE) {
TAILQ_REMOVE(&vm_page_queue_inactive, m, pageq);
m->flags &= ~PG_INACTIVE;
cnt.v_inactive_count--;
}
if (m->wire_count == 0) {
if (m->flags & PG_ACTIVE)
panic("vm_page_activate: already active");
TAILQ_INSERT_TAIL(&vm_page_queue_active, m, pageq);
m->flags |= PG_ACTIVE;
cnt.v_active_count++;
}
}
/*
* 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);
m->flags &= ~PG_CLEAN;
pmap_zero_page(VM_PAGE_TO_PHYS(m));
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);
dest_m->flags &= ~PG_CLEAN;
pmap_copy_page(VM_PAGE_TO_PHYS(src_m), VM_PAGE_TO_PHYS(dest_m));
}
#ifdef VM_PAGE_ALLOC_MEMORY_STATS
#define STAT_INCR(v) (v)++
#define STAT_DECR(v) do { \
if ((v) == 0) \
printf("%s:%d -- Already 0!\n", __FILE__, __LINE__); \
else \
(v)--; \
} while (0)
u_long vm_page_alloc_memory_npages;
#else
#define STAT_INCR(v)
#define STAT_DECR(v)
#endif
/*
* vm_page_alloc_memory:
*
* Allocate physical pages conforming to the restrictions
* provided:
*
* size The size of the allocation,
* rounded to page size.
*
* low The low address of the allowed
* allocation range.
*
* high The high address of the allowed
* allocation range.
*
* alignment Allocation must be aligned to this
* power-of-two boundary.
*
* boundary No segment in the allocation may
* cross this power-of-two boundary
* (relative to zero).
*
* The allocated pages are placed at the tail of `rlist'; `rlist'
* is assumed to be properly initialized by the caller. The
* number of memory segments that the allocated memory may
* occupy is specified in the `nsegs' arguement.
*
* Returns 0 on success or an errno value to indicate mode
* of failure.
*
* XXX This implementation could be improved. It only
* XXX allocates a single segment.
*/
int
vm_page_alloc_memory(size, low, high, alignment, boundary,
rlist, nsegs, waitok)
vsize_t size;
vaddr_t low, high, alignment, boundary;
struct pglist *rlist;
int nsegs, waitok;
{
paddr_t try, idxpa, lastidxpa;
int psi;
struct vm_page *vm_page_array;
int s, tryidx, idx, end, error;
vm_page_t m;
u_long pagemask;
#ifdef DEBUG
vm_page_t tp;
#endif
#ifdef DIAGNOSTIC
if ((alignment & (alignment - 1)) != 0)
panic("vm_page_alloc_memory: alignment must be power of 2");
if ((boundary & (boundary - 1)) != 0)
panic("vm_page_alloc_memory: boundary must be power of 2");
#endif
/*
* Our allocations are always page granularity, so our alignment
* must be, too.
*/
if (alignment < PAGE_SIZE)
alignment = PAGE_SIZE;
size = round_page(size);
try = roundup(low, alignment);
if (boundary != 0 && boundary < size)
return (EINVAL);
pagemask = ~(boundary - 1);
/* Default to "lose". */
error = ENOMEM;
/*
* Block all memory allocation and lock the free list.
*/
s = splimp();
simple_lock(&vm_page_queue_free_lock);
/* Are there even any free pages? */
if (vm_page_queue_free.tqh_first == NULL)
goto out;
for (;; try += alignment) {
if (try + size > high) {
/*
* We've run past the allowable range.
*/
goto out;
}
/*
* Make sure this is a managed physical page.
*/
if ((psi = vm_physseg_find(atop(try), &idx)) == -1)
continue; /* managed? */
if (vm_physseg_find(atop(try + size), NULL) != psi)
continue; /* end must be in this segment */
tryidx = idx;
end = idx + (size / PAGE_SIZE);
vm_page_array = vm_physmem[psi].pgs;
/* XXX: emulates old global vm_page_array */
/*
* Found a suitable starting page. See of the range
* is free.
*/
for (; idx < end; idx++) {
if (VM_PAGE_IS_FREE(&vm_page_array[idx]) == 0) {
/*
* Page not available.
*/
break;
}
idxpa = VM_PAGE_TO_PHYS(&vm_page_array[idx]);
if (idx > tryidx) {
lastidxpa =
VM_PAGE_TO_PHYS(&vm_page_array[idx - 1]);
if ((lastidxpa + PAGE_SIZE) != idxpa) {
/*
* Region not contiguous.
*/
break;
}
if (boundary != 0 &&
((lastidxpa ^ idxpa) & pagemask) != 0) {
/*
* Region crosses boundary.
*/
break;
}
}
}
if (idx == end) {
/*
* Woo hoo! Found one.
*/
break;
}
}
/*
* Okay, we have a chunk of memory that conforms to
* the requested constraints.
*/
idx = tryidx;
while (idx < end) {
m = &vm_page_array[idx];
#ifdef DEBUG
for (tp = vm_page_queue_free.tqh_first; tp != NULL;
tp = tp->pageq.tqe_next) {
if (tp == m)
break;
}
if (tp == NULL)
panic("vm_page_alloc_memory: page not on freelist");
#endif
TAILQ_REMOVE(&vm_page_queue_free, m, pageq);
cnt.v_free_count--;
m->flags = PG_CLEAN;
m->object = NULL;
m->wire_count = 0;
TAILQ_INSERT_TAIL(rlist, m, pageq);
idx++;
STAT_INCR(vm_page_alloc_memory_npages);
}
error = 0;
out:
simple_unlock(&vm_page_queue_free_lock);
splx(s);
return (error);
}
/*
* vm_page_free_memory:
*
* Free a list of pages previously allocated by vm_page_alloc_memory().
* The pages are assumed to have no mappings.
*/
void
vm_page_free_memory(list)
struct pglist *list;
{
vm_page_t m;
int s;
/*
* Block all memory allocation and lock the free list.
*/
s = splimp();
simple_lock(&vm_page_queue_free_lock);
while ((m = list->tqh_first) != NULL) {
TAILQ_REMOVE(list, m, pageq);
m->flags = PG_FREE;
TAILQ_INSERT_TAIL(&vm_page_queue_free, m, pageq);
cnt.v_free_count++;
STAT_DECR(vm_page_alloc_memory_npages);
}
simple_unlock(&vm_page_queue_free_lock);
splx(s);
}
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