/*
- * Copyright (c) 2000-2003 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
*
- * @APPLE_LICENSE_HEADER_START@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
*
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License"). You may not use this file except in compliance with the
- * License. Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
*
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
- * License for the specific language governing rights and limitations
- * under the License.
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
*
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
*/
/*
* @OSF_COPYRIGHT@
* Virtual memory object module.
*/
-#ifdef MACH_BSD
-/* remove as part of compoenent support merge */
-extern int vnode_pager_workaround;
-#endif
-
#include <mach_pagemap.h>
#include <task_swapper.h>
#include <mach/memory_object_default.h>
#include <mach/memory_object_control_server.h>
#include <mach/vm_param.h>
+
+#include <ipc/ipc_types.h>
#include <ipc/ipc_port.h>
+
+#include <kern/kern_types.h>
#include <kern/assert.h>
#include <kern/lock.h>
#include <kern/queue.h>
#include <kern/host.h>
#include <kern/host_statistics.h>
#include <kern/processor.h>
+#include <kern/misc_protos.h>
+
#include <vm/memory_object.h>
#include <vm/vm_fault.h>
#include <vm/vm_map.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pageout.h>
-#include <kern/misc_protos.h>
+#include <vm/vm_protos.h>
/*
* Virtual memory objects maintain the actual data
*/
/* Forward declarations for internal functions. */
-static void _vm_object_allocate(
- vm_object_size_t size,
- vm_object_t object);
-
static kern_return_t vm_object_terminate(
vm_object_t object);
static void vm_object_deactivate_all_pages(
vm_object_t object);
-static void vm_object_abort_activity(
- vm_object_t object);
-
static kern_return_t vm_object_copy_call(
vm_object_t src_object,
vm_object_offset_t src_offset,
#define vm_object_hash(pager) \
((((unsigned)pager) >> VM_OBJECT_HASH_SHIFT) % VM_OBJECT_HASH_COUNT)
+void vm_object_hash_entry_free(
+ vm_object_hash_entry_t entry);
+
+static void vm_object_reap(vm_object_t object);
+static void vm_object_reap_async(vm_object_t object);
+static void vm_object_reaper_thread(void);
+static queue_head_t vm_object_reaper_queue; /* protected by vm_object_cache_lock() */
+unsigned int vm_object_reap_count = 0;
+unsigned int vm_object_reap_count_async = 0;
+
/*
* vm_object_hash_lookup looks up a pager in the hashtable
* and returns the corresponding entry, with optional removal.
vm_object_hash_entry_free(
vm_object_hash_entry_t entry)
{
- zfree(vm_object_hash_zone, (vm_offset_t)entry);
+ zfree(vm_object_hash_zone, entry);
}
/*
* Returns a new object with the given size.
*/
-static void
+__private_extern__ void
_vm_object_allocate(
vm_object_size_t size,
vm_object_t object)
*object = vm_object_template;
queue_init(&object->memq);
queue_init(&object->msr_q);
-#ifdef UBC_DEBUG
+#ifdef UPL_DEBUG
queue_init(&object->uplq);
-#endif /* UBC_DEBUG */
+#endif /* UPL_DEBUG */
vm_object_lock_init(object);
object->size = size;
}
__private_extern__ void
vm_object_bootstrap(void)
{
- register i;
+ register int i;
vm_object_zone = zinit((vm_size_t) sizeof(struct vm_object),
round_page_32(512*1024),
"vm objects");
queue_init(&vm_object_cached_list);
- mutex_init(&vm_object_cached_lock_data, ETAP_VM_OBJ_CACHE);
+ mutex_init(&vm_object_cached_lock_data, 0);
vm_object_hash_zone =
zinit((vm_size_t) sizeof (struct vm_object_hash_entry),
/* memq; Lock; init after allocation */
vm_object_template.size = 0;
- vm_object_template.frozen_size = 0;
+ vm_object_template.memq_hint = VM_PAGE_NULL;
vm_object_template.ref_count = 1;
#if TASK_SWAPPER
vm_object_template.res_count = 1;
vm_object_template.pager = MEMORY_OBJECT_NULL;
vm_object_template.paging_offset = 0;
- vm_object_template.pager_request = PAGER_REQUEST_NULL;
+ vm_object_template.pager_control = MEMORY_OBJECT_CONTROL_NULL;
/* msr_q; init after allocation */
vm_object_template.copy_strategy = MEMORY_OBJECT_COPY_SYMMETRIC;
vm_object_template.private = FALSE;
vm_object_template.pageout = FALSE;
vm_object_template.alive = TRUE;
- vm_object_template.lock_in_progress = FALSE;
- vm_object_template.lock_restart = FALSE;
+ vm_object_template.purgable = VM_OBJECT_NONPURGABLE;
vm_object_template.silent_overwrite = FALSE;
vm_object_template.advisory_pageout = FALSE;
vm_object_template.shadowed = FALSE;
#endif /* MACH_PAGEMAP */
}
+void
+vm_object_reaper_init(void)
+{
+ kern_return_t kr;
+ thread_t thread;
+
+ queue_init(&vm_object_reaper_queue);
+ kr = kernel_thread_start_priority(
+ (thread_continue_t) vm_object_reaper_thread,
+ NULL,
+ BASEPRI_PREEMPT - 1,
+ &thread);
+ if (kr != KERN_SUCCESS) {
+ panic("failed to launch vm_object_reaper_thread kr=0x%x", kr);
+ }
+ thread_deallocate(thread);
+}
+
__private_extern__ void
vm_object_init(void)
{
register vm_object_t object)
{
boolean_t retry_cache_trim = FALSE;
- vm_object_t shadow;
+ vm_object_t shadow = VM_OBJECT_NULL;
// if(object)dbgLog(object, object->ref_count, object->can_persist, 3); /* (TEST/DEBUG) */
// else dbgLog(object, 0, 0, 3); /* (TEST/DEBUG) */
if ((object->ref_count > 1) || object->terminating) {
object->ref_count--;
vm_object_res_deallocate(object);
- vm_object_unlock(object);
vm_object_cache_unlock();
+
+ if (object->ref_count == 1 &&
+ object->shadow != VM_OBJECT_NULL) {
+ /*
+ * We don't use this VM object anymore. We
+ * would like to collapse it into its parent(s),
+ * but we don't have any pointers back to these
+ * parent object(s).
+ * But we can try and collapse this object with
+ * its own shadows, in case these are useless
+ * too...
+ */
+ vm_object_collapse(object, 0);
+ }
+
+ vm_object_unlock(object);
if (retry_cache_trim &&
((object = vm_object_cache_trim(TRUE)) !=
VM_OBJECT_NULL)) {
* This object is not cachable; terminate it.
*/
XPR(XPR_VM_OBJECT,
- "vm_o_deallocate: !cacheable 0x%X res %d paging_ops %d thread 0x%lX ref %d\n",
- (integer_t)object, object->resident_page_count,
- object->paging_in_progress,
- (natural_t)current_thread(),object->ref_count);
+ "vm_o_deallocate: !cacheable 0x%X res %d paging_ops %d thread 0x%p ref %d\n",
+ (integer_t)object, object->resident_page_count,
+ object->paging_in_progress,
+ (void *)current_thread(),object->ref_count);
VM_OBJ_RES_DECR(object); /* XXX ? */
/*
vm_object_terminate(
register vm_object_t object)
{
- memory_object_t pager;
register vm_page_t p;
vm_object_t shadow_object;
vm_object_unlock(shadow_object);
}
+ if (FALSE && object->paging_in_progress != 0) {
+ /*
+ * There are still some paging_in_progress references
+ * on this object, meaning that there are some paging
+ * or other I/O operations in progress for this VM object.
+ * Such operations take some paging_in_progress references
+ * up front to ensure that the object doesn't go away, but
+ * they may also need to acquire a reference on the VM object,
+ * to map it in kernel space, for example. That means that
+ * they may end up releasing the last reference on the VM
+ * object, triggering its termination, while still holding
+ * paging_in_progress references. Waiting for these
+ * pending paging_in_progress references to go away here would
+ * deadlock.
+ *
+ * To avoid deadlocking, we'll let the vm_object_reaper_thread
+ * complete the VM object termination if it still holds
+ * paging_in_progress references at this point.
+ *
+ * No new paging_in_progress should appear now that the
+ * VM object is "terminating" and not "alive".
+ */
+ vm_object_reap_async(object);
+ vm_object_cache_unlock();
+ vm_object_unlock(object);
+ return KERN_SUCCESS;
+ }
+ /* complete the VM object termination */
+ vm_object_reap(object);
+ object = VM_OBJECT_NULL;
+ /* cache lock and object lock were released by vm_object_reap() */
+
+ return KERN_SUCCESS;
+}
+
+/*
+ * vm_object_reap():
+ *
+ * Complete the termination of a VM object after it's been marked
+ * as "terminating" and "!alive" by vm_object_terminate().
+ *
+ * The VM object cache and the VM object must be locked by caller.
+ * The locks will be released on return and the VM object is no longer valid.
+ */
+void
+vm_object_reap(
+ vm_object_t object)
+{
+ memory_object_t pager;
+ vm_page_t p;
+
+#if DEBUG
+ mutex_assert(&vm_object_cached_lock_data, MA_OWNED);
+ mutex_assert(&object->Lock, MA_OWNED);
+#endif /* DEBUG */
+
+ vm_object_reap_count++;
+
/*
- * The pageout daemon might be playing with our pages.
- * Now that the object is dead, it won't touch any more
- * pages, but some pages might already be on their way out.
- * Hence, we wait until the active paging activities have ceased
- * before we break the association with the pager itself.
+ * The pageout daemon might be playing with our pages.
+ * Now that the object is dead, it won't touch any more
+ * pages, but some pages might already be on their way out.
+ * Hence, we wait until the active paging activities have
+ * ceased before we break the association with the pager
+ * itself.
*/
while (object->paging_in_progress != 0) {
vm_object_cache_unlock();
vm_object_lock(object);
}
+ assert(object->paging_in_progress == 0);
pager = object->pager;
object->pager = MEMORY_OBJECT_NULL;
if (pager != MEMORY_OBJECT_NULL)
- memory_object_control_disable(object->pager_request);
+ memory_object_control_disable(object->pager_control);
vm_object_cache_unlock();
object->ref_count--;
* if some faults on this object were aborted.
*/
if (object->pageout) {
- assert(shadow_object != VM_OBJECT_NULL);
- assert(shadow_object == object->shadow);
+ assert(object->shadow != VM_OBJECT_NULL);
vm_pageout_object_terminate(object);
VM_PAGE_FREE(p);
}
} else if (!queue_empty(&object->memq)) {
- panic("vm_object_terminate: queue just emptied isn't");
+ panic("vm_object_reap: queue just emptied isn't");
}
assert(object->paging_in_progress == 0);
/*
* Free the space for the object.
*/
- zfree(vm_object_zone, (vm_offset_t) object);
- return KERN_SUCCESS;
+ zfree(vm_object_zone, object);
+ object = VM_OBJECT_NULL;
+}
+
+void
+vm_object_reap_async(
+ vm_object_t object)
+{
+#if DEBUG
+ mutex_assert(&vm_object_cached_lock_data, MA_OWNED);
+ mutex_assert(&object->Lock, MA_OWNED);
+#endif /* DEBUG */
+
+ vm_object_reap_count_async++;
+
+ /* enqueue the VM object... */
+ queue_enter(&vm_object_reaper_queue, object,
+ vm_object_t, cached_list);
+ /* ... and wake up the reaper thread */
+ thread_wakeup((event_t) &vm_object_reaper_queue);
+}
+
+void
+vm_object_reaper_thread(void)
+{
+ vm_object_t object;
+
+ vm_object_cache_lock();
+
+ while (!queue_empty(&vm_object_reaper_queue)) {
+ queue_remove_first(&vm_object_reaper_queue,
+ object,
+ vm_object_t,
+ cached_list);
+ vm_object_lock(object);
+ assert(object->terminating);
+ assert(!object->alive);
+
+ vm_object_reap(object);
+ /* cache is unlocked and object is no longer valid */
+ object = VM_OBJECT_NULL;
+
+ vm_object_cache_lock();
+ }
+
+ /* wait for more work... */
+ assert_wait((event_t) &vm_object_reaper_queue, THREAD_UNINT);
+ vm_object_cache_unlock();
+ thread_block((thread_continue_t) vm_object_reaper_thread);
+ /*NOTREACHED*/
}
/*
memory_object_deallocate(pager);
}
-/*
- * Routine: vm_object_abort_activity [internal use only]
- * Purpose:
- * Abort paging requests pending on this object.
- * In/out conditions:
- * The object is locked on entry and exit.
- */
-static void
-vm_object_abort_activity(
- vm_object_t object)
-{
- register
- vm_page_t p;
- vm_page_t next;
-
- XPR(XPR_VM_OBJECT, "vm_object_abort_activity, object 0x%X\n",
- (integer_t)object, 0, 0, 0, 0);
-
- /*
- * Abort all activity that would be waiting
- * for a result on this memory object.
- *
- * We could also choose to destroy all pages
- * that we have in memory for this object, but
- * we don't.
- */
-
- p = (vm_page_t) queue_first(&object->memq);
- while (!queue_end(&object->memq, (queue_entry_t) p)) {
- next = (vm_page_t) queue_next(&p->listq);
-
- /*
- * If it's being paged in, destroy it.
- * If an unlock has been requested, start it again.
- */
-
- if (p->busy && p->absent) {
- VM_PAGE_FREE(p);
- }
- else {
- if (p->unlock_request != VM_PROT_NONE)
- p->unlock_request = VM_PROT_NONE;
- PAGE_WAKEUP(p);
- }
-
- p = next;
- }
-
- /*
- * Wake up threads waiting for the memory object to
- * become ready.
- */
-
- object->pager_ready = TRUE;
- vm_object_wakeup(object, VM_OBJECT_EVENT_PAGER_READY);
-}
-
/*
* Routine: vm_object_destroy
* Purpose:
kern_return_t
vm_object_destroy(
vm_object_t object,
- kern_return_t reason)
+ __unused kern_return_t reason)
{
memory_object_t old_pager;
old_pager = object->pager;
object->pager = MEMORY_OBJECT_NULL;
if (old_pager != MEMORY_OBJECT_NULL)
- memory_object_control_disable(object->pager_request);
+ memory_object_control_disable(object->pager_control);
vm_object_cache_unlock();
/*
if ((m->wire_count == 0) && (!m->private) && (!m->gobbled) && (!m->busy)) {
+ assert(!m->laundry);
+
m->reference = FALSE;
pmap_clear_reference(m->phys_page);
}
VM_PAGE_QUEUES_REMOVE(m);
+ assert(!m->laundry);
+ assert(m->object != kernel_object);
+ assert(m->pageq.next == NULL &&
+ m->pageq.prev == NULL);
if(m->zero_fill) {
queue_enter_first(
&vm_page_queue_zf,
vm_object_pmap_protect(
register vm_object_t object,
register vm_object_offset_t offset,
- vm_size_t size,
+ vm_object_size_t size,
pmap_t pmap,
- vm_offset_t pmap_start,
+ vm_map_offset_t pmap_start,
vm_prot_t prot)
{
if (object == VM_OBJECT_NULL)
return;
- size = round_page_64(size);
- offset = trunc_page_64(offset);
+ size = vm_object_round_page(size);
+ offset = vm_object_trunc_page(offset);
vm_object_lock(object);
assert(object->internal);
while (TRUE) {
- if (object->resident_page_count > atop_32(size) / 2 &&
- pmap != PMAP_NULL) {
+ if (ptoa_64(object->resident_page_count) > size/2 && pmap != PMAP_NULL) {
vm_object_unlock(object);
pmap_protect(pmap, pmap_start, pmap_start + size, prot);
return;
/* if we are doing large ranges with respect to resident */
/* page count then we should interate over pages otherwise */
/* inverse page look-up will be faster */
- if ((object->resident_page_count / 4) < atop_32(size)) {
+ if (ptoa_64(object->resident_page_count / 4) < size) {
vm_page_t p;
vm_object_offset_t end;
queue_iterate(&object->memq, p, vm_page_t, listq) {
if (!p->fictitious &&
(offset <= p->offset) && (p->offset < end)) {
+ vm_map_offset_t start;
- vm_offset_t start = pmap_start +
- (vm_offset_t)(p->offset - offset);
-
- pmap_protect(pmap, start, start + PAGE_SIZE, prot);
+ start = pmap_start + p->offset - offset;
+ pmap_protect(pmap, start, start + PAGE_SIZE_64, prot);
}
}
} else {
if (pmap != PMAP_NULL) {
for(target_off = offset;
- target_off < end; target_off += PAGE_SIZE) {
- if(p = vm_page_lookup(object, target_off)) {
- vm_offset_t start = pmap_start +
+ target_off < end;
+ target_off += PAGE_SIZE) {
+ p = vm_page_lookup(object, target_off);
+ if (p != VM_PAGE_NULL) {
+ vm_offset_t start;
+ start = pmap_start +
(vm_offset_t)(p->offset - offset);
pmap_protect(pmap, start,
start + PAGE_SIZE, prot);
} else {
for(target_off = offset;
target_off < end; target_off += PAGE_SIZE) {
- if(p = vm_page_lookup(object, target_off)) {
+ p = vm_page_lookup(object, target_off);
+ if (p != VM_PAGE_NULL) {
pmap_page_protect(p->phys_page,
prot & ~p->page_lock);
}
new_object = vm_object_allocate(size);
new_offset = 0;
+ vm_object_lock(new_object);
assert(size == trunc_page_64(size)); /* Will the loop terminate? */
while ((new_page = vm_page_alloc(new_object, new_offset))
== VM_PAGE_NULL) {
if (!vm_page_wait(interruptible)) {
+ vm_object_unlock(new_object);
vm_object_deallocate(new_object);
+ vm_object_deallocate(src_object);
*_result_object = VM_OBJECT_NULL;
return(MACH_SEND_INTERRUPTED);
}
case VM_FAULT_INTERRUPTED:
vm_page_free(new_page);
+ vm_object_unlock(new_object);
vm_object_deallocate(new_object);
vm_object_deallocate(src_object);
*_result_object = VM_OBJECT_NULL;
vm_page_lock_queues();
vm_page_free(new_page);
vm_page_unlock_queues();
+ vm_object_unlock(new_object);
vm_object_deallocate(new_object);
vm_object_deallocate(src_object);
*_result_object = VM_OBJECT_NULL;
* Lose the extra reference, and return our object.
*/
+ vm_object_unlock(new_object);
vm_object_deallocate(src_object);
*_result_object = new_object;
return(KERN_SUCCESS);
__private_extern__ boolean_t
vm_object_copy_quickly(
vm_object_t *_object, /* INOUT */
- vm_object_offset_t offset, /* IN */
- vm_object_size_t size, /* IN */
+ __unused vm_object_offset_t offset, /* IN */
+ __unused vm_object_size_t size, /* IN */
boolean_t *_src_needs_copy, /* OUT */
boolean_t *_dst_needs_copy) /* OUT */
{
static int copy_delayed_max_collisions = 0;
static int copy_delayed_lock_contention = 0;
static int copy_delayed_protect_iterate = 0;
-static int copy_delayed_protect_lookup = 0;
-static int copy_delayed_protect_lookup_wait = 0;
/*
* Routine: vm_object_copy_delayed [internal]
* needed).
*/
- if (new_copy != VM_OBJECT_NULL) {
- vm_object_unlock(new_copy);
- vm_object_deallocate(new_copy);
- }
-
if (old_copy->size < copy_size) {
/*
* We can't perform a delayed copy if any of the
if (p->wire_count > 0) {
vm_object_unlock(old_copy);
vm_object_unlock(src_object);
+
+ if (new_copy != VM_OBJECT_NULL) {
+ vm_object_unlock(new_copy);
+ vm_object_deallocate(new_copy);
+ }
+
return VM_OBJECT_NULL;
} else {
pmap_page_protect(p->phys_page,
vm_object_reference_locked(old_copy);
vm_object_unlock(old_copy);
vm_object_unlock(src_object);
+
+ if (new_copy != VM_OBJECT_NULL) {
+ vm_object_unlock(new_copy);
+ vm_object_deallocate(new_copy);
+ }
+
return(old_copy);
}
*/
#if 0
+static void vm_object_abort_activity(
+ vm_object_t object);
+
+/*
+ * Routine: vm_object_abort_activity [internal use only]
+ * Purpose:
+ * Abort paging requests pending on this object.
+ * In/out conditions:
+ * The object is locked on entry and exit.
+ */
+static void
+vm_object_abort_activity(
+ vm_object_t object)
+{
+ register
+ vm_page_t p;
+ vm_page_t next;
+
+ XPR(XPR_VM_OBJECT, "vm_object_abort_activity, object 0x%X\n",
+ (integer_t)object, 0, 0, 0, 0);
+
+ /*
+ * Abort all activity that would be waiting
+ * for a result on this memory object.
+ *
+ * We could also choose to destroy all pages
+ * that we have in memory for this object, but
+ * we don't.
+ */
+
+ p = (vm_page_t) queue_first(&object->memq);
+ while (!queue_end(&object->memq, (queue_entry_t) p)) {
+ next = (vm_page_t) queue_next(&p->listq);
+
+ /*
+ * If it's being paged in, destroy it.
+ * If an unlock has been requested, start it again.
+ */
+
+ if (p->busy && p->absent) {
+ VM_PAGE_FREE(p);
+ }
+ else {
+ if (p->unlock_request != VM_PROT_NONE)
+ p->unlock_request = VM_PROT_NONE;
+ PAGE_WAKEUP(p);
+ }
+
+ p = next;
+ }
+
+ /*
+ * Wake up threads waiting for the memory object to
+ * become ready.
+ */
+
+ object->pager_ready = TRUE;
+ vm_object_wakeup(object, VM_OBJECT_EVENT_PAGER_READY);
+}
+
/*
* Routine: vm_object_pager_dead
*
entry = VM_OBJECT_HASH_ENTRY_NULL;
assert_wait((event_t) pager, THREAD_UNINT);
vm_object_cache_unlock();
- thread_block((void (*)(void))0);
+ thread_block(THREAD_CONTINUE_NULL);
vm_object_cache_lock();
}
} while (entry == VM_OBJECT_HASH_ENTRY_NULL);
vm_object_hash_entry_free(new_entry);
if (must_init) {
- pager_request_t pager_request;
+ memory_object_control_t control;
/*
* Allocate request port.
*/
- pager_request = memory_object_control_allocate(object);
- assert (pager_request != PAGER_REQUEST_NULL);
+ control = memory_object_control_allocate(object);
+ assert (control != MEMORY_OBJECT_CONTROL_NULL);
vm_object_lock(object);
+ assert(object != kernel_object);
/*
* Copy the reference we were given.
/* copy strategy invalid until set by memory manager */
object->copy_strategy = MEMORY_OBJECT_COPY_INVALID;
}
- object->pager_request = pager_request;
+ object->pager_control = control;
object->pager_ready = FALSE;
vm_object_unlock(object);
*/
(void) memory_object_init(pager,
- object->pager_request,
+ object->pager_control,
PAGE_SIZE);
vm_object_lock(object);
XPR(XPR_VM_OBJECT, "vm_object_pager_create, object 0x%X\n",
(integer_t)object, 0,0,0,0);
+ assert(object != kernel_object);
+
if (memory_manager_default_check() != KERN_SUCCESS)
return;
vm_object_t object)
{
memory_object_t pager;
- pager_request_t pager_request;
if ((pager = object->pager) != MEMORY_OBJECT_NULL) {
vm_object_hash_entry_t entry;
static int vm_external_discarded;
static int vm_external_collapsed;
+unsigned long vm_object_collapse_encrypted = 0;
+
/*
* Routine: vm_object_do_collapse
* Purpose:
new_offset = (p->offset - backing_offset);
assert(!p->busy || p->absent);
-
+
/*
* If the parent has a page here, or if
* this page falls outside the parent,
if (p->offset < backing_offset || new_offset >= size) {
VM_PAGE_FREE(p);
} else {
+ /*
+ * ENCRYPTED SWAP:
+ * The encryption key includes the "pager" and the
+ * "paging_offset". These might not be the same in
+ * the new object, so we can't just move an encrypted
+ * page from one object to the other. We can't just
+ * decrypt the page here either, because that would drop
+ * the object lock.
+ * The caller should check for encrypted pages before
+ * attempting to collapse.
+ */
+ ASSERT_PAGE_DECRYPTED(p);
+
pp = vm_page_lookup(object, new_offset);
if (pp == VM_PAGE_NULL) {
assert(entry != VM_OBJECT_HASH_ENTRY_NULL);
entry->object = object;
object->pager_created = backing_object->pager_created;
- object->pager_request = backing_object->pager_request;
+ object->pager_control = backing_object->pager_control;
object->pager_ready = backing_object->pager_ready;
object->pager_initialized = backing_object->pager_initialized;
object->cluster_size = backing_object->cluster_size;
object->paging_offset =
backing_object->paging_offset + backing_offset;
- if (object->pager_request != PAGER_REQUEST_NULL) {
- memory_object_control_collapse(object->pager_request,
+ if (object->pager_control != MEMORY_OBJECT_CONTROL_NULL) {
+ memory_object_control_collapse(object->pager_control,
object);
}
}
* moves from within backing_object to within object.
*/
+ assert(!object->phys_contiguous);
+ assert(!backing_object->phys_contiguous);
object->shadow = backing_object->shadow;
- object->shadow_offset += backing_object->shadow_offset;
+ if (object->shadow) {
+ object->shadow_offset += backing_object->shadow_offset;
+ } else {
+ /* no shadow, therefore no shadow offset... */
+ object->shadow_offset = 0;
+ }
assert((object->shadow == VM_OBJECT_NULL) ||
(object->shadow->copy != backing_object));
XPR(XPR_VM_OBJECT, "vm_object_collapse, collapsed 0x%X\n",
(integer_t)backing_object, 0,0,0,0);
- zfree(vm_object_zone, (vm_offset_t) backing_object);
+ zfree(vm_object_zone, backing_object);
object_collapses++;
}
vm_object_reference(backing_object->shadow);
#endif /* TASK_SWAPPER */
+ assert(!object->phys_contiguous);
+ assert(!backing_object->phys_contiguous);
object->shadow = backing_object->shadow;
- object->shadow_offset += backing_object->shadow_offset;
+ if (object->shadow) {
+ object->shadow_offset += backing_object->shadow_offset;
+ } else {
+ /* no shadow, therefore no shadow offset... */
+ object->shadow_offset = 0;
+ }
/*
* Backing object might have had a copy pointer
* Requires that the object be locked and the page queues be unlocked.
*
*/
+static unsigned long vm_object_collapse_calls = 0;
+static unsigned long vm_object_collapse_objects = 0;
+static unsigned long vm_object_collapse_do_collapse = 0;
+static unsigned long vm_object_collapse_do_bypass = 0;
__private_extern__ void
vm_object_collapse(
register vm_object_t object,
register vm_object_t backing_object;
register unsigned int rcount;
register unsigned int size;
+ vm_object_offset_t collapse_min_offset;
+ vm_object_offset_t collapse_max_offset;
+ vm_page_t page;
+ vm_object_t original_object;
+
+ vm_object_collapse_calls++;
if (! vm_object_collapse_allowed && ! vm_object_bypass_allowed) {
return;
XPR(XPR_VM_OBJECT, "vm_object_collapse, obj 0x%X\n",
(integer_t)object, 0,0,0,0);
+ if (object == VM_OBJECT_NULL)
+ return;
+
+ original_object = object;
+
while (TRUE) {
+ vm_object_collapse_objects++;
/*
* Verify that the conditions are right for either
* collapse or bypass:
- *
- * The object exists and no pages in it are currently
- * being paged out, and
*/
- if (object == VM_OBJECT_NULL ||
- object->paging_in_progress != 0 ||
- object->absent_count != 0)
- return;
/*
* There is a backing object, and
*/
- if ((backing_object = object->shadow) == VM_OBJECT_NULL)
+ backing_object = object->shadow;
+ if (backing_object == VM_OBJECT_NULL) {
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
return;
+ }
+ /*
+ * No pages in the object are currently
+ * being paged out, and
+ */
+ if (object->paging_in_progress != 0 ||
+ object->absent_count != 0) {
+ /* try and collapse the rest of the shadow chain */
+ vm_object_lock(backing_object);
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
+ }
+
vm_object_lock(backing_object);
/*
if (!backing_object->internal ||
backing_object->paging_in_progress != 0) {
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
/*
*/
if (backing_object->shadow != VM_OBJECT_NULL &&
backing_object->shadow->copy == backing_object) {
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
/*
if (backing_object->ref_count == 1 &&
(!object->pager_created
#if !MACH_PAGEMAP
- || !backing_object->pager_created
+ || !backing_object->pager_created
#endif /*!MACH_PAGEMAP */
) && vm_object_collapse_allowed) {
XPR(XPR_VM_OBJECT,
- "vm_object_collapse: %x to %x, pager %x, pager_request %x\n",
+ "vm_object_collapse: %x to %x, pager %x, pager_control %x\n",
(integer_t)backing_object, (integer_t)object,
(integer_t)backing_object->pager,
- (integer_t)backing_object->pager_request, 0);
+ (integer_t)backing_object->pager_control, 0);
/*
* We need the cache lock for collapsing,
*/
if (! vm_object_cache_lock_try()) {
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
vm_object_unlock(backing_object);
return;
}
+ /*
+ * ENCRYPTED SWAP
+ * We can't collapse the object if it contains
+ * any encypted page, because the encryption key
+ * includes the <object,offset> info. We can't
+ * drop the object lock in vm_object_do_collapse()
+ * so we can't decrypt the page there either.
+ */
+ if (vm_pages_encrypted) {
+ collapse_min_offset = object->shadow_offset;
+ collapse_max_offset =
+ object->shadow_offset + object->size;
+ queue_iterate(&backing_object->memq,
+ page, vm_page_t, listq) {
+ if (page->encrypted &&
+ (page->offset >=
+ collapse_min_offset) &&
+ (page->offset <
+ collapse_max_offset)) {
+ /*
+ * We found an encrypted page
+ * in the backing object,
+ * within the range covered
+ * by the parent object: we can
+ * not collapse them.
+ */
+ vm_object_collapse_encrypted++;
+ vm_object_cache_unlock();
+ goto try_bypass;
+ }
+ }
+ }
+
/*
* Collapse the object with its backing
* object, and try again with the object's
*/
vm_object_do_collapse(object, backing_object);
+ vm_object_collapse_do_collapse++;
continue;
}
-
+ try_bypass:
/*
* Collapsing the backing object was not possible
* or permitted, so let's try bypassing it.
*/
if (! vm_object_bypass_allowed) {
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
size = atop(object->size);
rcount = object->resident_page_count;
if (rcount != size) {
- vm_object_size_t size;
vm_object_offset_t offset;
vm_object_offset_t backing_offset;
unsigned int backing_rcount;
&& (backing_object->existence_map == VM_EXTERNAL_NULL)
#endif /* MACH_PAGEMAP */
) {
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
/*
&& (object->existence_map == VM_EXTERNAL_NULL)
#endif /* MACH_PAGEMAP */
) {
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
/*
!EXISTS_IN_OBJECT(object, hint_offset, rcount)) {
/* dependency right at the hint */
object->cow_hint = (vm_offset_t)hint_offset;
- vm_object_unlock(backing_object);
- return;
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
}
/*
!EXISTS_IN_OBJECT(object, offset, rc)) {
/* found a dependency */
object->cow_hint = (vm_offset_t)offset;
- vm_object_unlock(backing_object);
- return;
+ break;
}
- p = queue_next(p);
+ p = (vm_page_t) queue_next(&p->listq);
} while (--backing_rcount);
+ if (backing_rcount != 0 ) {
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
+ object = backing_object;
+ continue;
+ }
}
/*
!EXISTS_IN_OBJECT(object, offset, rcount)) {
/* found a dependency */
object->cow_hint = (vm_offset_t)offset;
- vm_object_unlock(backing_object);
- return;
+ break;
+ }
+ }
+ if (offset != hint_offset) {
+ /* try and collapse the rest of the shadow chain */
+ if (object != original_object) {
+ vm_object_unlock(object);
}
+ object = backing_object;
+ continue;
}
}
}
*/
vm_object_do_bypass(object, backing_object);
+ vm_object_collapse_do_bypass++;
/*
* Try again with this object's new backing object.
continue;
}
+
+ if (object != original_object) {
+ vm_object_unlock(object);
+ }
}
/*
if (p != VM_PAGE_NULL) {
assert(!p->cleaning && !p->pageout);
if (!p->fictitious)
- pmap_page_protect(p->phys_page,
- VM_PROT_NONE);
+ pmap_disconnect(p->phys_page);
VM_PAGE_FREE(p);
}
}
if ((start <= p->offset) && (p->offset < end)) {
assert(!p->cleaning && !p->pageout);
if (!p->fictitious)
- pmap_page_protect(p->phys_page,
- VM_PROT_NONE);
+ pmap_disconnect(p->phys_page);
VM_PAGE_FREE(p);
}
p = next;
register vm_object_t prev_object,
vm_object_t next_object,
vm_object_offset_t prev_offset,
- vm_object_offset_t next_offset,
+ __unused vm_object_offset_t next_offset,
vm_object_size_t prev_size,
vm_object_size_t next_size)
{
* . paged out
* . shadows another object
* . has a copy elsewhere
+ * . is purgable
* . paging references (pages might be in page-list)
*/
(prev_object->shadow != VM_OBJECT_NULL) ||
(prev_object->copy != VM_OBJECT_NULL) ||
(prev_object->true_share != FALSE) ||
+ (prev_object->purgable != VM_OBJECT_NONPURGABLE) ||
(prev_object->paging_in_progress != 0)) {
vm_object_unlock(prev_object);
return(FALSE);
*/
void
vm_external_print(
- vm_external_map_t map,
- vm_size_t size)
+ vm_external_map_t emap,
+ vm_size_t size)
{
- if (map == VM_EXTERNAL_NULL) {
+ if (emap == VM_EXTERNAL_NULL) {
printf("0 ");
} else {
vm_size_t existence_size = stob(size);
printf("{ size=%d, map=[", existence_size);
if (existence_size > 0) {
- print_bitstring(map[0]);
+ print_bitstring(emap[0]);
}
if (existence_size > 1) {
- print_bitstring(map[1]);
+ print_bitstring(emap[1]);
}
if (existence_size > 2) {
printf("...");
- print_bitstring(map[existence_size-1]);
+ print_bitstring(emap[existence_size-1]);
}
printf("] }\n");
}
vm_follow_object(
vm_object_t object)
{
- extern db_indent;
-
int count = 0;
int orig_db_indent = db_indent;
*/
void
vm_object_print(
- vm_object_t object,
- boolean_t have_addr,
- int arg_count,
- char *modif)
+ db_addr_t db_addr,
+ __unused boolean_t have_addr,
+ __unused int arg_count,
+ __unused char *modif)
{
+ vm_object_t object;
register vm_page_t p;
- extern db_indent;
- char *s;
+ const char *s;
register int count;
+ object = (vm_object_t) (long) db_addr;
if (object == VM_OBJECT_NULL)
return;
iprintf("size=0x%x", object->size);
printf(", cluster=0x%x", object->cluster_size);
- printf(", frozen=0x%x", object->frozen_size);
+ printf(", memq_hint=%p", object->memq_hint);
printf(", ref_count=%d\n", object->ref_count);
iprintf("");
#if TASK_SWAPPER
if (object->shadow) {
register int i = 0;
vm_object_t shadow = object;
- while(shadow = shadow->shadow)
+ while((shadow = shadow->shadow))
i++;
printf(" (depth %d)", i);
}
iprintf("pager=0x%x", object->pager);
printf(", paging_offset=0x%x", object->paging_offset);
- printf(", pager_request=0x%x\n", object->pager_request);
+ printf(", pager_control=0x%x\n", object->pager_control);
iprintf("copy_strategy=%d[", object->copy_strategy);
switch (object->copy_strategy) {
(object->pageout ? "" : "!"),
(object->internal ? "internal" : "external"),
(object->temporary ? "temporary" : "permanent"));
- iprintf("%salive, %slock_in_progress, %slock_restart, %sshadowed, %scached, %sprivate\n",
+ iprintf("%salive, %spurgable, %spurgable_volatile, %spurgable_empty, %sshadowed, %scached, %sprivate\n",
(object->alive ? "" : "!"),
- (object->lock_in_progress ? "" : "!"),
- (object->lock_restart ? "" : "!"),
+ ((object->purgable != VM_OBJECT_NONPURGABLE) ? "" : "!"),
+ ((object->purgable == VM_OBJECT_PURGABLE_VOLATILE) ? "" : "!"),
+ ((object->purgable == VM_OBJECT_PURGABLE_EMPTY) ? "" : "!"),
(object->shadowed ? "" : "!"),
(vm_object_cached(object) ? "" : "!"),
(object->private ? "" : "!"));
}
count++;
- printf("(off=0x%X,page=0x%X)", p->offset, (integer_t) p);
+ printf("(off=0x%llX,page=%p)", p->offset, p);
p = (vm_page_t) queue_next(&p->listq);
}
if (count != 0) {
vm_page_unlock_queues();
} else if (m->phys_page != base_page) {
/* pmap call to clear old mapping */
- pmap_page_protect(m->phys_page,
- VM_PROT_NONE);
+ pmap_disconnect(m->phys_page);
m->phys_page = base_page;
}
+
+ /*
+ * ENCRYPTED SWAP:
+ * We're not pointing to the same
+ * physical page any longer and the
+ * contents of the new one are not
+ * supposed to be encrypted.
+ * XXX What happens to the original
+ * physical page. Is it lost ?
+ */
+ m->encrypted = FALSE;
+
} else {
while ((m = vm_page_grab_fictitious())
== VM_PAGE_NULL)
__private_extern__ kern_return_t
memory_object_free_from_cache(
- host_t host,
+ __unused host_t host,
int *pager_id,
int *count)
{
int object_released = 0;
- int i;
register vm_object_t object = VM_OBJECT_NULL;
vm_object_t shadow;
VM_OBJECT_EVENT_PAGER_READY,
THREAD_UNINT);
}
- *control = object->pager_request;
+ *control = object->pager_control;
vm_object_unlock(object);
}
return (KERN_SUCCESS);
return KERN_SUCCESS;
}
}
+ /*NOTREACHED*/
+ assert(0);
+ return KERN_FAILURE;
}
int flags,
vm_prot_t prot)
{
- vm_object_offset_t original_offset = offset;
- boolean_t should_flush=flags & MEMORY_OBJECT_DATA_FLUSH;
+ __unused boolean_t should_flush;
+
+ should_flush = flags & MEMORY_OBJECT_DATA_FLUSH;
XPR(XPR_MEMORY_OBJECT,
"vm_o_lock_request, obj 0x%X off 0x%X size 0x%X flags %X prot %X\n",
vm_object_paging_begin(object);
(void)vm_object_update(object,
- offset, size, should_return, flags, prot);
+ offset, size, NULL, NULL, should_return, flags, prot);
vm_object_paging_end(object);
vm_object_unlock(object);
return (KERN_SUCCESS);
}
+/*
+ * Empty a purgable object by grabbing the physical pages assigned to it and
+ * putting them on the free queue without writing them to backing store, etc.
+ * When the pages are next touched they will be demand zero-fill pages. We
+ * skip pages which are busy, being paged in/out, wired, etc. We do _not_
+ * skip referenced/dirty pages, pages on the active queue, etc. We're more
+ * than happy to grab these since this is a purgable object. We mark the
+ * object as "empty" after reaping its pages.
+ *
+ * On entry the object and page queues are locked, the object must be a
+ * purgable object with no delayed copies pending.
+ */
+unsigned int
+vm_object_purge(vm_object_t object)
+{
+ vm_page_t p, next;
+ unsigned int num_purged_pages;
+ vm_page_t local_freeq;
+ unsigned long local_freed;
+ int purge_loop_quota;
+/* free pages as soon as we gather PURGE_BATCH_FREE_LIMIT pages to free */
+#define PURGE_BATCH_FREE_LIMIT 50
+/* release page queues lock every PURGE_LOOP_QUOTA iterations */
+#define PURGE_LOOP_QUOTA 100
+ num_purged_pages = 0;
+ if (object->purgable == VM_OBJECT_NONPURGABLE)
+ return num_purged_pages;
+
+ object->purgable = VM_OBJECT_PURGABLE_EMPTY;
+
+ assert(object->copy == VM_OBJECT_NULL);
+ assert(object->copy_strategy == MEMORY_OBJECT_COPY_NONE);
+ purge_loop_quota = PURGE_LOOP_QUOTA;
+
+ local_freeq = VM_PAGE_NULL;
+ local_freed = 0;
+
+ /*
+ * Go through the object's resident pages and try and discard them.
+ */
+ next = (vm_page_t)queue_first(&object->memq);
+ while (!queue_end(&object->memq, (queue_entry_t)next)) {
+ p = next;
+ next = (vm_page_t)queue_next(&next->listq);
+
+ if (purge_loop_quota-- == 0) {
+ /*
+ * Avoid holding the page queues lock for too long.
+ * Let someone else take it for a while if needed.
+ * Keep holding the object's lock to guarantee that
+ * the object's page list doesn't change under us
+ * while we yield.
+ */
+ if (local_freeq != VM_PAGE_NULL) {
+ /*
+ * Flush our queue of pages to free.
+ */
+ vm_page_free_list(local_freeq);
+ local_freeq = VM_PAGE_NULL;
+ local_freed = 0;
+ }
+ vm_page_unlock_queues();
+ mutex_pause();
+ vm_page_lock_queues();
+
+ /* resume with the current page and a new quota */
+ purge_loop_quota = PURGE_LOOP_QUOTA;
+ }
+
+
+ if (p->busy || p->cleaning || p->laundry ||
+ p->list_req_pending) {
+ /* page is being acted upon, so don't mess with it */
+ continue;
+ }
+ if (p->wire_count) {
+ /* don't discard a wired page */
+ continue;
+ }
+
+ if (p->tabled) {
+ /* clean up the object/offset table */
+ vm_page_remove(p);
+ }
+ if (p->absent) {
+ /* update the object's count of absent pages */
+ vm_object_absent_release(object);
+ }
+
+ /* we can discard this page */
+
+ /* advertize that this page is in a transition state */
+ p->busy = TRUE;
+
+ if (p->no_isync == TRUE) {
+ /* the page hasn't been mapped yet */
+ /* (optimization to delay the i-cache sync) */
+ } else {
+ /* unmap the page */
+ int refmod_state;
+
+ refmod_state = pmap_disconnect(p->phys_page);
+ if (refmod_state & VM_MEM_MODIFIED) {
+ p->dirty = TRUE;
+ }
+ }
+
+ if (p->dirty || p->precious) {
+ /* we saved the cost of cleaning this page ! */
+ num_purged_pages++;
+ vm_page_purged_count++;
+ }
+
+ /* remove page from active or inactive queue... */
+ VM_PAGE_QUEUES_REMOVE(p);
+
+ /* ... and put it on our queue of pages to free */
+ assert(!p->laundry);
+ assert(p->object != kernel_object);
+ assert(p->pageq.next == NULL &&
+ p->pageq.prev == NULL);
+ p->pageq.next = (queue_entry_t) local_freeq;
+ local_freeq = p;
+ if (++local_freed >= PURGE_BATCH_FREE_LIMIT) {
+ /* flush our queue of pages to free */
+ vm_page_free_list(local_freeq);
+ local_freeq = VM_PAGE_NULL;
+ local_freed = 0;
+ }
+ }
+
+ /* flush our local queue of pages to free one last time */
+ if (local_freeq != VM_PAGE_NULL) {
+ vm_page_free_list(local_freeq);
+ local_freeq = VM_PAGE_NULL;
+ local_freed = 0;
+ }
+
+ return num_purged_pages;
+}
+
+/*
+ * vm_object_purgable_control() allows the caller to control and investigate the
+ * state of a purgable object. A purgable object is created via a call to
+ * vm_allocate() with VM_FLAGS_PURGABLE specified. A purgable object will
+ * never be coalesced with any other object -- even other purgable objects --
+ * and will thus always remain a distinct object. A purgable object has
+ * special semantics when its reference count is exactly 1. If its reference
+ * count is greater than 1, then a purgable object will behave like a normal
+ * object and attempts to use this interface will result in an error return
+ * of KERN_INVALID_ARGUMENT.
+ *
+ * A purgable object may be put into a "volatile" state which will make the
+ * object's pages elligable for being reclaimed without paging to backing
+ * store if the system runs low on memory. If the pages in a volatile
+ * purgable object are reclaimed, the purgable object is said to have been
+ * "emptied." When a purgable object is emptied the system will reclaim as
+ * many pages from the object as it can in a convenient manner (pages already
+ * en route to backing store or busy for other reasons are left as is). When
+ * a purgable object is made volatile, its pages will generally be reclaimed
+ * before other pages in the application's working set. This semantic is
+ * generally used by applications which can recreate the data in the object
+ * faster than it can be paged in. One such example might be media assets
+ * which can be reread from a much faster RAID volume.
+ *
+ * A purgable object may be designated as "non-volatile" which means it will
+ * behave like all other objects in the system with pages being written to and
+ * read from backing store as needed to satisfy system memory needs. If the
+ * object was emptied before the object was made non-volatile, that fact will
+ * be returned as the old state of the purgable object (see
+ * VM_PURGABLE_SET_STATE below). In this case, any pages of the object which
+ * were reclaimed as part of emptying the object will be refaulted in as
+ * zero-fill on demand. It is up to the application to note that an object
+ * was emptied and recreate the objects contents if necessary. When a
+ * purgable object is made non-volatile, its pages will generally not be paged
+ * out to backing store in the immediate future. A purgable object may also
+ * be manually emptied.
+ *
+ * Finally, the current state (non-volatile, volatile, volatile & empty) of a
+ * volatile purgable object may be queried at any time. This information may
+ * be used as a control input to let the application know when the system is
+ * experiencing memory pressure and is reclaiming memory.
+ *
+ * The specified address may be any address within the purgable object. If
+ * the specified address does not represent any object in the target task's
+ * virtual address space, then KERN_INVALID_ADDRESS will be returned. If the
+ * object containing the specified address is not a purgable object, then
+ * KERN_INVALID_ARGUMENT will be returned. Otherwise, KERN_SUCCESS will be
+ * returned.
+ *
+ * The control parameter may be any one of VM_PURGABLE_SET_STATE or
+ * VM_PURGABLE_GET_STATE. For VM_PURGABLE_SET_STATE, the in/out parameter
+ * state is used to set the new state of the purgable object and return its
+ * old state. For VM_PURGABLE_GET_STATE, the current state of the purgable
+ * object is returned in the parameter state.
+ *
+ * The in/out parameter state may be one of VM_PURGABLE_NONVOLATILE,
+ * VM_PURGABLE_VOLATILE or VM_PURGABLE_EMPTY. These, respectively, represent
+ * the non-volatile, volatile and volatile/empty states described above.
+ * Setting the state of a purgable object to VM_PURGABLE_EMPTY will
+ * immediately reclaim as many pages in the object as can be conveniently
+ * collected (some may have already been written to backing store or be
+ * otherwise busy).
+ *
+ * The process of making a purgable object non-volatile and determining its
+ * previous state is atomic. Thus, if a purgable object is made
+ * VM_PURGABLE_NONVOLATILE and the old state is returned as
+ * VM_PURGABLE_VOLATILE, then the purgable object's previous contents are
+ * completely intact and will remain so until the object is made volatile
+ * again. If the old state is returned as VM_PURGABLE_EMPTY then the object
+ * was reclaimed while it was in a volatile state and its previous contents
+ * have been lost.
+ */
+/*
+ * The object must be locked.
+ */
+kern_return_t
+vm_object_purgable_control(
+ vm_object_t object,
+ vm_purgable_t control,
+ int *state)
+{
+ int old_state;
+ vm_page_t p;
+
+ if (object == VM_OBJECT_NULL) {
+ /*
+ * Object must already be present or it can't be purgable.
+ */
+ return KERN_INVALID_ARGUMENT;
+ }
+
+ /*
+ * Get current state of the purgable object.
+ */
+ switch (object->purgable) {
+ case VM_OBJECT_NONPURGABLE:
+ return KERN_INVALID_ARGUMENT;
+
+ case VM_OBJECT_PURGABLE_NONVOLATILE:
+ old_state = VM_PURGABLE_NONVOLATILE;
+ break;
+
+ case VM_OBJECT_PURGABLE_VOLATILE:
+ old_state = VM_PURGABLE_VOLATILE;
+ break;
+
+ case VM_OBJECT_PURGABLE_EMPTY:
+ old_state = VM_PURGABLE_EMPTY;
+ break;
+
+ default:
+ old_state = VM_PURGABLE_NONVOLATILE;
+ panic("Bad state (%d) for purgable object!\n",
+ object->purgable);
+ /*NOTREACHED*/
+ }
+
+ /* purgable cant have delayed copies - now or in the future */
+ assert(object->copy == VM_OBJECT_NULL);
+ assert(object->copy_strategy == MEMORY_OBJECT_COPY_NONE);
+
+ /*
+ * Execute the desired operation.
+ */
+ if (control == VM_PURGABLE_GET_STATE) {
+ *state = old_state;
+ return KERN_SUCCESS;
+ }
+
+ switch (*state) {
+ case VM_PURGABLE_NONVOLATILE:
+ vm_page_lock_queues();
+ if (object->purgable != VM_OBJECT_PURGABLE_NONVOLATILE) {
+ assert(vm_page_purgeable_count >=
+ object->resident_page_count);
+ vm_page_purgeable_count -= object->resident_page_count;
+ }
+
+ object->purgable = VM_OBJECT_PURGABLE_NONVOLATILE;
+
+ /*
+ * If the object wasn't emptied, then mark all pages of the
+ * object as referenced in order to give them a complete turn
+ * of the virtual memory "clock" before becoming candidates
+ * for paging out (if the system is suffering from memory
+ * pressure). We don't really need to set the pmap reference
+ * bits (which would be expensive) since the software copies
+ * are believed if they're set to true ...
+ */
+ if (old_state != VM_PURGABLE_EMPTY) {
+ for (p = (vm_page_t)queue_first(&object->memq);
+ !queue_end(&object->memq, (queue_entry_t)p);
+ p = (vm_page_t)queue_next(&p->listq))
+ p->reference = TRUE;
+ }
+
+ vm_page_unlock_queues();
+
+ break;
+
+ case VM_PURGABLE_VOLATILE:
+ vm_page_lock_queues();
+
+ if (object->purgable != VM_OBJECT_PURGABLE_VOLATILE &&
+ object->purgable != VM_OBJECT_PURGABLE_EMPTY) {
+ vm_page_purgeable_count += object->resident_page_count;
+ }
+
+ object->purgable = VM_OBJECT_PURGABLE_VOLATILE;
+
+ /*
+ * We want the newly volatile purgable object to be a
+ * candidate for the pageout scan before other pages in the
+ * application if the system is suffering from memory
+ * pressure. To do this, we move a page of the object from
+ * the active queue onto the inactive queue in order to
+ * promote the object for early reclaim. We only need to move
+ * a single page since the pageout scan will reap the entire
+ * purgable object if it finds a single page in a volatile
+ * state. Obviously we don't do this if there are no pages
+ * associated with the object or we find a page of the object
+ * already on the inactive queue.
+ */
+ for (p = (vm_page_t)queue_first(&object->memq);
+ !queue_end(&object->memq, (queue_entry_t)p);
+ p = (vm_page_t)queue_next(&p->listq)) {
+ if (p->inactive) {
+ /* already a page on the inactive queue */
+ break;
+ }
+ if (p->active && !p->busy) {
+ /* found one we can move */
+ vm_page_deactivate(p);
+ break;
+ }
+ }
+ vm_page_unlock_queues();
+
+ break;
+
+
+ case VM_PURGABLE_EMPTY:
+ vm_page_lock_queues();
+ if (object->purgable != VM_OBJECT_PURGABLE_VOLATILE &&
+ object->purgable != VM_OBJECT_PURGABLE_EMPTY) {
+ vm_page_purgeable_count += object->resident_page_count;
+ }
+ (void) vm_object_purge(object);
+ vm_page_unlock_queues();
+ break;
+
+ }
+ *state = old_state;
+
+ return KERN_SUCCESS;
+}
#if TASK_SWAPPER
/*
* This is also needed as number of vnodes can be dynamically scaled.
*/
kern_return_t
-adjust_vm_object_cache(vm_size_t oval, vm_size_t nval)
+adjust_vm_object_cache(
+ __unused vm_size_t oval,
+ vm_size_t nval)
{
vm_object_cached_max = nval;
vm_object_cache_trim(FALSE);
}
#endif /* MACH_BSD */
+
+/*
+ * vm_object_transpose
+ *
+ * This routine takes two VM objects of the same size and exchanges
+ * their backing store.
+ * The objects should be "quiesced" via a UPL operation with UPL_SET_IO_WIRE
+ * and UPL_BLOCK_ACCESS if they are referenced anywhere.
+ *
+ * The VM objects must not be locked by caller.
+ */
+kern_return_t
+vm_object_transpose(
+ vm_object_t object1,
+ vm_object_t object2,
+ vm_object_size_t transpose_size)
+{
+ vm_object_t tmp_object;
+ kern_return_t retval;
+ boolean_t object1_locked, object2_locked;
+ boolean_t object1_paging, object2_paging;
+ vm_page_t page;
+ vm_object_offset_t page_offset;
+
+ tmp_object = VM_OBJECT_NULL;
+ object1_locked = FALSE; object2_locked = FALSE;
+ object1_paging = FALSE; object2_paging = FALSE;
+
+ if (object1 == object2 ||
+ object1 == VM_OBJECT_NULL ||
+ object2 == VM_OBJECT_NULL) {
+ /*
+ * If the 2 VM objects are the same, there's
+ * no point in exchanging their backing store.
+ */
+ retval = KERN_INVALID_VALUE;
+ goto done;
+ }
+
+ vm_object_lock(object1);
+ object1_locked = TRUE;
+ if (object1->copy || object1->shadow || object1->shadowed ||
+ object1->purgable != VM_OBJECT_NONPURGABLE) {
+ /*
+ * We don't deal with copy or shadow objects (yet).
+ */
+ retval = KERN_INVALID_VALUE;
+ goto done;
+ }
+ /*
+ * Since we're about to mess with the object's backing store,
+ * mark it as "paging_in_progress". Note that this is not enough
+ * to prevent any paging activity on this object, so the caller should
+ * have "quiesced" the objects beforehand, via a UPL operation with
+ * UPL_SET_IO_WIRE (to make sure all the pages are there and wired)
+ * and UPL_BLOCK_ACCESS (to mark the pages "busy").
+ */
+ vm_object_paging_begin(object1);
+ object1_paging = TRUE;
+ vm_object_unlock(object1);
+ object1_locked = FALSE;
+
+ /*
+ * Same as above for the 2nd object...
+ */
+ vm_object_lock(object2);
+ object2_locked = TRUE;
+ if (object2->copy || object2->shadow || object2->shadowed ||
+ object2->purgable != VM_OBJECT_NONPURGABLE) {
+ retval = KERN_INVALID_VALUE;
+ goto done;
+ }
+ vm_object_paging_begin(object2);
+ object2_paging = TRUE;
+ vm_object_unlock(object2);
+ object2_locked = FALSE;
+
+ /*
+ * Allocate a temporary VM object to hold object1's contents
+ * while we copy object2 to object1.
+ */
+ tmp_object = vm_object_allocate(transpose_size);
+ vm_object_lock(tmp_object);
+ vm_object_paging_begin(tmp_object);
+ tmp_object->can_persist = FALSE;
+
+ /*
+ * Since we need to lock both objects at the same time,
+ * make sure we always lock them in the same order to
+ * avoid deadlocks.
+ */
+ if (object1 < object2) {
+ vm_object_lock(object1);
+ vm_object_lock(object2);
+ } else {
+ vm_object_lock(object2);
+ vm_object_lock(object1);
+ }
+ object1_locked = TRUE;
+ object2_locked = TRUE;
+
+ if (object1->size != object2->size ||
+ object1->size != transpose_size) {
+ /*
+ * If the 2 objects don't have the same size, we can't
+ * exchange their backing stores or one would overflow.
+ * If their size doesn't match the caller's
+ * "transpose_size", we can't do it either because the
+ * transpose operation will affect the entire span of
+ * the objects.
+ */
+ retval = KERN_INVALID_VALUE;
+ goto done;
+ }
+
+
+ /*
+ * Transpose the lists of resident pages.
+ */
+ if (object1->phys_contiguous || queue_empty(&object1->memq)) {
+ /*
+ * No pages in object1, just transfer pages
+ * from object2 to object1. No need to go through
+ * an intermediate object.
+ */
+ while (!queue_empty(&object2->memq)) {
+ page = (vm_page_t) queue_first(&object2->memq);
+ vm_page_rename(page, object1, page->offset);
+ }
+ assert(queue_empty(&object2->memq));
+ } else if (object2->phys_contiguous || queue_empty(&object2->memq)) {
+ /*
+ * No pages in object2, just transfer pages
+ * from object1 to object2. No need to go through
+ * an intermediate object.
+ */
+ while (!queue_empty(&object1->memq)) {
+ page = (vm_page_t) queue_first(&object1->memq);
+ vm_page_rename(page, object2, page->offset);
+ }
+ assert(queue_empty(&object1->memq));
+ } else {
+ /* transfer object1's pages to tmp_object */
+ vm_page_lock_queues();
+ while (!queue_empty(&object1->memq)) {
+ page = (vm_page_t) queue_first(&object1->memq);
+ page_offset = page->offset;
+ vm_page_remove(page);
+ page->offset = page_offset;
+ queue_enter(&tmp_object->memq, page, vm_page_t, listq);
+ }
+ vm_page_unlock_queues();
+ assert(queue_empty(&object1->memq));
+ /* transfer object2's pages to object1 */
+ while (!queue_empty(&object2->memq)) {
+ page = (vm_page_t) queue_first(&object2->memq);
+ vm_page_rename(page, object1, page->offset);
+ }
+ assert(queue_empty(&object2->memq));
+ /* transfer tmp_object's pages to object1 */
+ while (!queue_empty(&tmp_object->memq)) {
+ page = (vm_page_t) queue_first(&tmp_object->memq);
+ queue_remove(&tmp_object->memq, page,
+ vm_page_t, listq);
+ vm_page_insert(page, object2, page->offset);
+ }
+ assert(queue_empty(&tmp_object->memq));
+ }
+
+ /* no need to transpose the size: they should be identical */
+ assert(object1->size == object2->size);
+
+#define __TRANSPOSE_FIELD(field) \
+MACRO_BEGIN \
+ tmp_object->field = object1->field; \
+ object1->field = object2->field; \
+ object2->field = tmp_object->field; \
+MACRO_END
+
+ assert(!object1->copy);
+ assert(!object2->copy);
+
+ assert(!object1->shadow);
+ assert(!object2->shadow);
+
+ __TRANSPOSE_FIELD(shadow_offset); /* used by phys_contiguous objects */
+ __TRANSPOSE_FIELD(pager);
+ __TRANSPOSE_FIELD(paging_offset);
+
+ __TRANSPOSE_FIELD(pager_control);
+ /* update the memory_objects' pointers back to the VM objects */
+ if (object1->pager_control != MEMORY_OBJECT_CONTROL_NULL) {
+ memory_object_control_collapse(object1->pager_control,
+ object1);
+ }
+ if (object2->pager_control != MEMORY_OBJECT_CONTROL_NULL) {
+ memory_object_control_collapse(object2->pager_control,
+ object2);
+ }
+
+ __TRANSPOSE_FIELD(absent_count);
+
+ assert(object1->paging_in_progress);
+ assert(object2->paging_in_progress);
+
+ __TRANSPOSE_FIELD(pager_created);
+ __TRANSPOSE_FIELD(pager_initialized);
+ __TRANSPOSE_FIELD(pager_ready);
+ __TRANSPOSE_FIELD(pager_trusted);
+ __TRANSPOSE_FIELD(internal);
+ __TRANSPOSE_FIELD(temporary);
+ __TRANSPOSE_FIELD(private);
+ __TRANSPOSE_FIELD(pageout);
+ __TRANSPOSE_FIELD(true_share);
+ __TRANSPOSE_FIELD(phys_contiguous);
+ __TRANSPOSE_FIELD(nophyscache);
+ __TRANSPOSE_FIELD(last_alloc);
+ __TRANSPOSE_FIELD(sequential);
+ __TRANSPOSE_FIELD(cluster_size);
+ __TRANSPOSE_FIELD(existence_map);
+ __TRANSPOSE_FIELD(cow_hint);
+ __TRANSPOSE_FIELD(wimg_bits);
+
+#undef __TRANSPOSE_FIELD
+
+ retval = KERN_SUCCESS;
+
+done:
+ /*
+ * Cleanup.
+ */
+ if (tmp_object != VM_OBJECT_NULL) {
+ vm_object_paging_end(tmp_object);
+ vm_object_unlock(tmp_object);
+ /*
+ * Re-initialize the temporary object to avoid
+ * deallocating a real pager.
+ */
+ _vm_object_allocate(transpose_size, tmp_object);
+ vm_object_deallocate(tmp_object);
+ tmp_object = VM_OBJECT_NULL;
+ }
+
+ if (object1_locked) {
+ vm_object_unlock(object1);
+ object1_locked = FALSE;
+ }
+ if (object2_locked) {
+ vm_object_unlock(object2);
+ object2_locked = FALSE;
+ }
+ if (object1_paging) {
+ vm_object_lock(object1);
+ vm_object_paging_end(object1);
+ vm_object_unlock(object1);
+ object1_paging = FALSE;
+ }
+ if (object2_paging) {
+ vm_object_lock(object2);
+ vm_object_paging_end(object2);
+ vm_object_unlock(object2);
+ object2_paging = FALSE;
+ }
+
+ return retval;
+}
projects / apple / xnu.git / blobdiff