/*
- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2001 Apple Computer, Inc. All rights reserved.
*
* @APPLE_LICENSE_HEADER_START@
*
#include <mach_pagemap.h>
#include <task_swapper.h>
+#include <mach/mach_types.h>
#include <mach/memory_object.h>
#include <mach/memory_object_default.h>
#include <mach/memory_object_control_server.h>
#include <mach/vm_param.h>
#include <ipc/ipc_port.h>
-#include <ipc/ipc_space.h>
#include <kern/assert.h>
#include <kern/lock.h>
#include <kern/queue.h>
* page of memory exists within exactly one object.
*
* An object is only deallocated when all "references"
- * are given up. Only one "reference" to a given
- * region of an object should be writeable.
+ * are given up.
*
* Associated with each object is a list of all resident
* memory pages belonging to that object; this list is
* maintained by the "vm_page" module, but locked by the object's
* lock.
*
- * Each object also records the memory object port
+ * Each object also records the memory object reference
* that is used by the kernel to request and write
- * back data (the memory object port, field "pager"),
- * and the ports provided to the memory manager, the server that
- * manages that data, to return data and control its
- * use (the memory object control port, field "pager_request")
- * and for naming (the memory object name port, field "pager_name").
+ * back data (the memory object, field "pager"), etc...
*
* Virtual memory objects are allocated to provide
* zero-filled memory (vm_allocate) or map a user-defined
*
* The kernel relies on a *default memory manager* to
* provide backing storage for the zero-filled virtual
- * memory objects. The memory object ports associated
+ * memory objects. The pager memory objects associated
* with these temporary virtual memory objects are only
- * generated and passed to the default memory manager
- * when it becomes necessary. Virtual memory objects
+ * requested from the default memory manager when it
+ * becomes necessary. Virtual memory objects
* that depend on the default memory manager are called
* "internal". The "pager_created" field is provided to
* indicate whether these ports have ever been allocated.
*/
/* Forward declarations for internal functions. */
-extern void _vm_object_allocate(
+static void _vm_object_allocate(
vm_object_size_t size,
vm_object_t object);
-extern kern_return_t vm_object_terminate(
+static kern_return_t vm_object_terminate(
vm_object_t object);
extern void vm_object_remove(
vm_object_t object);
-extern vm_object_t vm_object_cache_trim(
+static vm_object_t vm_object_cache_trim(
boolean_t called_from_vm_object_deallocate);
-extern void vm_object_deactivate_pages(
+static void vm_object_deactivate_all_pages(
vm_object_t object);
-extern void vm_object_abort_activity(
+static void vm_object_abort_activity(
vm_object_t object);
-extern kern_return_t vm_object_copy_call(
+static kern_return_t vm_object_copy_call(
vm_object_t src_object,
vm_object_offset_t src_offset,
vm_object_size_t size,
vm_object_t *_result_object);
-extern void vm_object_do_collapse(
+static void vm_object_do_collapse(
vm_object_t object,
vm_object_t backing_object);
-extern void vm_object_do_bypass(
+static void vm_object_do_bypass(
vm_object_t object,
vm_object_t backing_object);
-extern void memory_object_release(
- ipc_port_t pager,
- pager_request_t pager_request);
+static void vm_object_release_pager(
+ memory_object_t pager);
-zone_t vm_object_zone; /* vm backing store zone */
+static zone_t vm_object_zone; /* vm backing store zone */
/*
* All wired-down kernel memory belongs to a single virtual
* memory object (kernel_object) to avoid wasting data structures.
*/
-struct vm_object kernel_object_store;
-vm_object_t kernel_object = &kernel_object_store;
+static struct vm_object kernel_object_store;
+__private_extern__ vm_object_t kernel_object = &kernel_object_store;
/*
* The submap object is used as a placeholder for vm_map_submap
* is exported by the vm_map module. The storage is declared
* here because it must be initialized here.
*/
-struct vm_object vm_submap_object_store;
+static struct vm_object vm_submap_object_store;
/*
* Virtual memory objects are initialized from
*
* When adding a new field to the virtual memory
* object structure, be sure to add initialization
- * (see vm_object_init).
+ * (see _vm_object_allocate()).
*/
-struct vm_object vm_object_template;
+static struct vm_object vm_object_template;
/*
* Virtual memory objects that are not referenced by
* from the reference mechanism, so that the lock need
* not be held to make simple references.
*/
-queue_head_t vm_object_cached_list;
-int vm_object_cached_count;
-int vm_object_cached_high; /* highest # of cached objects */
-int vm_object_cached_max = 500; /* may be patched*/
+static queue_head_t vm_object_cached_list;
+static int vm_object_cached_count;
+static int vm_object_cached_high; /* highest # cached objects */
+static int vm_object_cached_max = 512; /* may be patched*/
-decl_mutex_data(,vm_object_cached_lock_data)
+static decl_mutex_data(,vm_object_cached_lock_data)
#define vm_object_cache_lock() \
mutex_lock(&vm_object_cached_lock_data)
mutex_unlock(&vm_object_cached_lock_data)
#define VM_OBJECT_HASH_COUNT 1024
-queue_head_t vm_object_hashtable[VM_OBJECT_HASH_COUNT];
-struct zone *vm_object_hash_zone;
+static queue_head_t vm_object_hashtable[VM_OBJECT_HASH_COUNT];
+static struct zone *vm_object_hash_zone;
struct vm_object_hash_entry {
queue_chain_t hash_link; /* hash chain link */
- ipc_port_t pager; /* pager we represent */
+ memory_object_t pager; /* pager we represent */
vm_object_t object; /* corresponding object */
boolean_t waiting; /* someone waiting for
* termination */
* and returns the corresponding entry, with optional removal.
*/
-vm_object_hash_entry_t
+static vm_object_hash_entry_t
vm_object_hash_lookup(
- ipc_port_t pager,
+ memory_object_t pager,
boolean_t remove_entry)
{
register queue_t bucket;
* pager / cache object association in the hashtable.
*/
-void
+static void
vm_object_hash_insert(
vm_object_hash_entry_t entry)
{
queue_enter(bucket, entry, vm_object_hash_entry_t, hash_link);
}
-vm_object_hash_entry_t
+static vm_object_hash_entry_t
vm_object_hash_entry_alloc(
- ipc_port_t pager)
+ memory_object_t pager)
{
vm_object_hash_entry_t entry;
* Returns a new object with the given size.
*/
-void
+static void
_vm_object_allocate(
vm_object_size_t size,
vm_object_t object)
object->size = size;
}
-vm_object_t
+__private_extern__ vm_object_t
vm_object_allocate(
vm_object_size_t size)
{
register vm_object_t object;
- register ipc_port_t port;
object = (vm_object_t) zalloc(vm_object_zone);
-// dbgLog(object, size, 0, 2); /* (TEST/DEBUG) */
-
- _vm_object_allocate(size, object);
+// dbgLog(object, size, 0, 2); /* (TEST/DEBUG) */
+
+ if (object != VM_OBJECT_NULL)
+ _vm_object_allocate(size, object);
return object;
}
*
* Initialize the VM objects module.
*/
-void
+__private_extern__ void
vm_object_bootstrap(void)
{
register i;
vm_object_template.copy = VM_OBJECT_NULL;
vm_object_template.shadow = VM_OBJECT_NULL;
vm_object_template.shadow_offset = (vm_object_offset_t) 0;
+ vm_object_template.cow_hint = 0;
vm_object_template.true_share = FALSE;
- vm_object_template.pager = IP_NULL;
+ vm_object_template.pager = MEMORY_OBJECT_NULL;
vm_object_template.paging_offset = 0;
vm_object_template.pager_request = PAGER_REQUEST_NULL;
/* msr_q; init after allocation */
vm_object_template.terminating = FALSE;
vm_object_template.shadow_severed = FALSE;
vm_object_template.phys_contiguous = FALSE;
+ vm_object_template.nophyscache = FALSE;
/* End bitfields */
/* cached_list; init after allocation */
#endif /* MACH_PAGEMAP */
}
-void
+__private_extern__ void
vm_object_init(void)
{
/*
*/
}
-#if TASK_SWAPPER
-/*
- * vm_object_res_deallocate
- *
- * (recursively) decrement residence counts on vm objects and their shadows.
- * Called from vm_object_deallocate and when swapping out an object.
- *
- * The object is locked, and remains locked throughout the function,
- * even as we iterate down the shadow chain. Locks on intermediate objects
- * will be dropped, but not the original object.
- *
- * NOTE: this function used to use recursion, rather than iteration.
- */
-
-void
-vm_object_res_deallocate(
- vm_object_t object)
-{
- vm_object_t orig_object = object;
- /*
- * Object is locked so it can be called directly
- * from vm_object_deallocate. Original object is never
- * unlocked.
- */
- assert(object->res_count > 0);
- while (--object->res_count == 0) {
- assert(object->ref_count >= object->res_count);
- vm_object_deactivate_pages(object);
- /* iterate on shadow, if present */
- if (object->shadow != VM_OBJECT_NULL) {
- vm_object_t tmp_object = object->shadow;
- vm_object_lock(tmp_object);
- if (object != orig_object)
- vm_object_unlock(object);
- object = tmp_object;
- assert(object->res_count > 0);
- } else
- break;
- }
- if (object != orig_object)
- vm_object_unlock(object);
-}
-
-/*
- * vm_object_res_reference
- *
- * Internal function to increment residence count on a vm object
- * and its shadows. It is called only from vm_object_reference, and
- * when swapping in a vm object, via vm_map_swap.
- *
- * The object is locked, and remains locked throughout the function,
- * even as we iterate down the shadow chain. Locks on intermediate objects
- * will be dropped, but not the original object.
- *
- * NOTE: this function used to use recursion, rather than iteration.
- */
-
-void
-vm_object_res_reference(
- vm_object_t object)
-{
- vm_object_t orig_object = object;
- /*
- * Object is locked, so this can be called directly
- * from vm_object_reference. This lock is never released.
- */
- while ((++object->res_count == 1) &&
- (object->shadow != VM_OBJECT_NULL)) {
- vm_object_t tmp_object = object->shadow;
-
- assert(object->ref_count >= object->res_count);
- vm_object_lock(tmp_object);
- if (object != orig_object)
- vm_object_unlock(object);
- object = tmp_object;
- }
- if (object != orig_object)
- vm_object_unlock(object);
- assert(orig_object->ref_count >= orig_object->res_count);
-}
-#endif /* TASK_SWAPPER */
-
-#if MACH_ASSERT
-/*
- * vm_object_reference:
- *
- * Gets another reference to the given object.
- */
-void
-vm_object_reference(
- register vm_object_t object)
-{
- if (object == VM_OBJECT_NULL)
- return;
-
- vm_object_lock(object);
- assert(object->ref_count > 0);
- object->ref_count++;
- vm_object_res_reference(object);
- vm_object_unlock(object);
-}
-#endif /* MACH_ASSERT */
-
/* remove the typedef below when emergency work-around is taken out */
typedef struct vnode_pager {
- ipc_port_t pager; /* pager */
- ipc_port_t pager_handle; /* pager handle */
- ipc_port_t vm_obj_handle; /* memory object's control handle */
- void *vnode_handle; /* vnode handle */
+ memory_object_t pager;
+ memory_object_t pager_handle; /* pager */
+ memory_object_control_t control_handle; /* memory object's control handle */
+ void *vnode_handle; /* vnode handle */
} *vnode_pager_t;
#define MIGHT_NOT_CACHE_SHADOWS 1
#if MIGHT_NOT_CACHE_SHADOWS
-int cache_shadows = TRUE;
+static int cache_shadows = TRUE;
#endif /* MIGHT_NOT_CACHE_SHADOWS */
/*
*
* No object may be locked.
*/
-void
+__private_extern__ void
vm_object_deallocate(
register vm_object_t object)
{
vm_object_cache_lock();
vm_object_lock(object);
- assert(object->alive);
+
+ assert(object->ref_count > 0);
+
+ /*
+ * If the object has a named reference, and only
+ * that reference would remain, inform the pager
+ * about the last "mapping" reference going away.
+ */
+ if ((object->ref_count == 2) && (object->named)) {
+ memory_object_t pager = object->pager;
+
+ /* Notify the Pager that there are no */
+ /* more mappers for this object */
+
+ if (pager != MEMORY_OBJECT_NULL) {
+ vm_object_unlock(object);
+ vm_object_cache_unlock();
+
+ memory_object_unmap(pager);
+
+ vm_object_cache_lock();
+ vm_object_lock(object);
+ assert(object->ref_count > 0);
+ }
+ }
/*
* Lose the reference. If other references
* until any pending initialization is completed.
*/
- assert(object->ref_count > 0);
- if ((object->ref_count > 1) || (object->terminating)) {
- /* if the object is terminating, it cannot go into */
- /* the cache and we obviously should not call */
- /* terminate again. */
+ /* if the object is terminating, it cannot go into */
+ /* the cache and we obviously should not call */
+ /* terminate again. */
+
+ if ((object->ref_count > 1) || object->terminating) {
object->ref_count--;
- {
- /* The following is an emergency work-around for */
- /* no-mappings left notification to UBC. This fix */
- /* violates numerous layering boundaries, is not */
- /* provable with respect to races for new mappings */
- /* from the UBC layer and is just plain ugly. The */
- /* proper fix requires a guarantee of state */
- /* between the vnode and the memory object and a */
- /* sequenced delivery of empty status. This can */
- /* be provided by the object_named interface and */
- /* the effort to convert over should be undertaken */
- /* at the earliest possible moment. */
- if(object->ref_count == 1) {
- vnode_pager_t vnode_pager;
- if(object->pager) {
- vnode_pager = (vnode_pager_t)
- vnode_port_hash_lookup(
- object->pager);
- if(vnode_pager) {
- extern void ubc_unmap(void *);
- ubc_unmap(vnode_pager->vnode_handle);
- }
- }
- }
- }
vm_object_res_deallocate(object);
vm_object_unlock(object);
vm_object_cache_unlock();
* way (can do it in-line, mostly).
*/
- if (object->can_persist) {
+ if ((object->can_persist) && (object->alive)) {
/*
* Now it is safe to decrement reference count,
* and to return if reference count is > 0.
queue_enter(&vm_object_cached_list, object,
vm_object_t, cached_list);
vm_object_cache_unlock();
- vm_object_deactivate_pages(object);
+ vm_object_deactivate_all_pages(object);
vm_object_unlock(object);
#if MIGHT_NOT_CACHE_SHADOWS
* Purpose:
* Free all resources associated with a vm_object.
* In/out conditions:
- * Upon entry, the object and the cache must be locked,
+ * Upon entry, the object must be locked,
* and the object must have exactly one reference.
*
* The shadow object reference is left alone.
* upon exit, the cache will be unlocked, and the
* object will cease to exist.
*/
-kern_return_t
+static kern_return_t
vm_object_terminate(
register vm_object_t object)
{
+ memory_object_t pager;
register vm_page_t p;
vm_object_t shadow_object;
XPR(XPR_VM_OBJECT, "vm_object_terminate, object 0x%X ref %d\n",
(integer_t)object, object->ref_count, 0, 0, 0);
- /*
- * Make sure the object isn't already being terminated
- */
-
- assert(object->alive);
- if(object->terminating) {
- vm_object_cache_unlock();
- object->ref_count -= 1;
- vm_object_unlock(object);
- return KERN_FAILURE;
- }
- object->terminating = TRUE;
-
- vm_object_cache_unlock();
if (!object->pageout && (!object->temporary || object->can_persist)
&& (object->pager != NULL || object->shadow_severed)) {
+ vm_object_cache_unlock();
while (!queue_empty(&object->memq)) {
/*
* Clear pager_trusted bit so that the pages get yanked
if (!p->dirty)
p->dirty = pmap_is_modified(p->phys_addr);
- if (p->dirty || p->precious) {
+ if ((p->dirty || p->precious) && !p->error && object->alive) {
p->busy = TRUE;
vm_object_paging_begin(object);
/* protect the object from re-use/caching while it */
VM_PAGE_FREE(p);
}
}
+ vm_object_unlock(object);
+ vm_object_cache_lock();
+ vm_object_lock(object);
}
+
+ /*
+ * Make sure the object isn't already being terminated
+ */
+ if(object->terminating) {
+ object->ref_count -= 1;
+ assert(object->ref_count > 0);
+ vm_object_cache_unlock();
+ vm_object_unlock(object);
+ return KERN_FAILURE;
+ }
+
+ /*
+ * Did somebody get a reference to the object while we were
+ * cleaning it?
+ */
if(object->ref_count != 1) {
object->ref_count -= 1;
+ assert(object->ref_count > 0);
vm_object_res_deallocate(object);
- object->terminating = FALSE;
- /* kick off anyone waiting on terminating */
- vm_object_paging_begin(object);
- vm_object_paging_end(object);
+ vm_object_cache_unlock();
vm_object_unlock(object);
return KERN_FAILURE;
}
- object->alive = FALSE;
-
/*
* Make sure no one can look us up now.
*/
- vm_object_cache_lock();
-
- if(object->pager != IP_NULL) {
- vm_object_hash_entry_t entry;
-
- entry = vm_object_hash_lookup(object->pager, FALSE);
- if (entry != VM_OBJECT_HASH_ENTRY_NULL)
- entry->object = VM_OBJECT_NULL;
- }
-
- vm_object_cache_unlock();
+ object->terminating = TRUE;
+ object->alive = FALSE;
+ vm_object_remove(object);
/*
* Detach the object from its shadow if we are the shadow's
* 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.
+ * Hence, we wait until the active paging activities have ceased
+ * before we break the association with the pager itself.
*/
- vm_object_paging_wait(object, THREAD_UNINT);
+ while (object->paging_in_progress != 0) {
+ vm_object_cache_unlock();
+ vm_object_wait(object,
+ VM_OBJECT_EVENT_PAGING_IN_PROGRESS,
+ THREAD_UNINT);
+ vm_object_cache_lock();
+ vm_object_lock(object);
+ }
+
+ pager = object->pager;
+ object->pager = MEMORY_OBJECT_NULL;
+
+ if (pager != MEMORY_OBJECT_NULL)
+ memory_object_control_disable(object->pager_request);
+ vm_object_cache_unlock();
+
object->ref_count--;
#if TASK_SWAPPER
assert(object->res_count == 0);
#endif /* TASK_SWAPPER */
-Restart:
assert (object->ref_count == 0);
/*
vm_pageout_object_terminate(object);
- } else if (object->temporary && ! object->can_persist ||
- object->pager == IP_NULL) {
+ } else if ((object->temporary && !object->can_persist) ||
+ (pager == MEMORY_OBJECT_NULL)) {
while (!queue_empty(&object->memq)) {
p = (vm_page_t) queue_first(&object->memq);
assert(object->paging_in_progress == 0);
assert(object->ref_count == 0);
- vm_object_remove(object);
-
/*
- * Throw away port rights... note that they may
- * already have been thrown away (by vm_object_destroy
- * or memory_object_destroy).
- *
- * Instead of destroying the control port,
- * we send all rights off to the memory manager,
- * using memory_object_terminate.
+ * If the pager has not already been released by
+ * vm_object_destroy, we need to terminate it and
+ * release our reference to it here.
*/
-
- vm_object_unlock(object);
- if (object->pager != IP_NULL) {
- /* consumes our rights for pager, pager_request */
- memory_object_release(object->pager, object->pager_request);
+ if (pager != MEMORY_OBJECT_NULL) {
+ vm_object_unlock(object);
+ vm_object_release_pager(pager);
+ vm_object_lock(object);
}
+
/* kick off anyone waiting on terminating */
- vm_object_lock(object);
+ object->terminating = FALSE;
vm_object_paging_begin(object);
vm_object_paging_end(object);
vm_object_unlock(object);
/*
* Free the space for the object.
*/
-
zfree(vm_object_zone, (vm_offset_t) object);
return KERN_SUCCESS;
}
* Purpose: Wake up anyone waiting for termination of a pager.
*/
-void
+static void
vm_object_pager_wakeup(
- ipc_port_t pager)
+ memory_object_t pager)
{
vm_object_hash_entry_t entry;
boolean_t waiting = FALSE;
}
/*
- * memory_object_release_name:
- * Enforces name semantic on memory_object reference count decrement
- * This routine should not be called unless the caller holds a name
- * reference gained through the memory_object_named_create or the
- * memory_object_rename call.
- * If the TERMINATE_IDLE flag is set, the call will return if the
- * reference count is not 1. i.e. idle with the only remaining reference
- * being the name.
- * If the decision is made to proceed the name field flag is set to
- * false and the reference count is decremented. If the RESPECT_CACHE
- * flag is set and the reference count has gone to zero, the
- * memory_object is checked to see if it is cacheable otherwise when
- * the reference count is zero, it is simply terminated.
+ * Routine: vm_object_release_pager
+ * Purpose: Terminate the pager and, upon completion,
+ * release our last reference to it.
+ * just like memory_object_terminate, except
+ * that we wake up anyone blocked in vm_object_enter
+ * waiting for termination message to be queued
+ * before calling memory_object_init.
*/
-
-kern_return_t
-memory_object_release_name(
- vm_object_t object,
- int flags)
+static void
+vm_object_release_pager(
+ memory_object_t pager)
{
- vm_object_t shadow;
- boolean_t original_object = TRUE;
- while (object != VM_OBJECT_NULL) {
+ /*
+ * Terminate the pager.
+ */
- /*
- * The cache holds a reference (uncounted) to
- * the object. We must locke it before removing
- * the object.
- *
- */
-
- vm_object_cache_lock();
- vm_object_lock(object);
- assert(object->alive);
- if(original_object)
- assert(object->named);
- assert(object->ref_count > 0);
+ (void) memory_object_terminate(pager);
- /*
- * We have to wait for initialization before
- * destroying or caching the object.
- */
+ /*
+ * Wakeup anyone waiting for this terminate
+ */
+ vm_object_pager_wakeup(pager);
- if (object->pager_created && !object->pager_initialized) {
- assert(!object->can_persist);
- vm_object_assert_wait(object,
- VM_OBJECT_EVENT_INITIALIZED,
- THREAD_UNINT);
- vm_object_unlock(object);
- vm_object_cache_unlock();
- thread_block((void (*)(void)) 0);
- continue;
- }
-
- if (((object->ref_count > 1)
- && (flags & MEMORY_OBJECT_TERMINATE_IDLE))
- || (object->terminating)) {
- vm_object_unlock(object);
- vm_object_cache_unlock();
- return KERN_FAILURE;
- } else {
- if (flags & MEMORY_OBJECT_RELEASE_NO_OP) {
- vm_object_unlock(object);
- vm_object_cache_unlock();
- return KERN_SUCCESS;
- }
- }
-
- if ((flags & MEMORY_OBJECT_RESPECT_CACHE) &&
- (object->ref_count == 1)) {
- if(original_object)
- object->named = FALSE;
- vm_object_unlock(object);
- vm_object_cache_unlock();
- /* let vm_object_deallocate push this thing into */
- /* the cache, if that it is where it is bound */
- vm_object_deallocate(object);
- return KERN_SUCCESS;
- }
- VM_OBJ_RES_DECR(object);
- shadow = object->pageout?VM_OBJECT_NULL:object->shadow;
- if(object->ref_count == 1) {
- if(vm_object_terminate(object) != KERN_SUCCESS) {
- if(original_object) {
- return KERN_FAILURE;
- } else {
- return KERN_SUCCESS;
- }
- }
- if (shadow != VM_OBJECT_NULL) {
- original_object = FALSE;
- object = shadow;
- continue;
- }
- return KERN_SUCCESS;
- } else {
- object->ref_count--;
- if(original_object)
- object->named = FALSE;
- vm_object_unlock(object);
- vm_object_cache_unlock();
- return KERN_SUCCESS;
- }
- }
-}
-
-/*
- * Routine: memory_object_release
- * Purpose: Terminate the pager and release port rights,
- * just like memory_object_terminate, except
- * that we wake up anyone blocked in vm_object_enter
- * waiting for termination message to be queued
- * before calling memory_object_init.
- */
-void
-memory_object_release(
- ipc_port_t pager,
- pager_request_t pager_request)
-{
-#ifdef MACH_BSD
- kern_return_t vnode_pager_terminate(ipc_port_t, ipc_port_t);
-#endif
-
- /*
- * Keep a reference to pager port;
- * the terminate might otherwise release all references.
- */
- ipc_port_copy_send(pager);
-
- /*
- * Terminate the pager.
- */
-
-#ifdef MACH_BSD
- if(((rpc_subsystem_t)pager_mux_hash_lookup(pager)) ==
- ((rpc_subsystem_t) &vnode_pager_workaround)) {
- (void) vnode_pager_terminate(pager, pager_request);
- } else {
- (void) memory_object_terminate(pager, pager_request);
- }
-#else
- (void) memory_object_terminate(pager, pager_request);
-#endif
-
- /*
- * Wakeup anyone waiting for this terminate
- */
- vm_object_pager_wakeup(pager);
-
- /*
- * Release reference to pager port.
- */
- ipc_port_release_send(pager);
-}
+ /*
+ * Release reference to pager.
+ */
+ memory_object_deallocate(pager);
+}
/*
* Routine: vm_object_abort_activity [internal use only]
* In/out conditions:
* The object is locked on entry and exit.
*/
-void
+static void
vm_object_abort_activity(
vm_object_t object)
{
}
/*
- * Routine: memory_object_destroy [user interface]
+ * Routine: vm_object_destroy
* Purpose:
- * Shut down a memory object, despite the
+ * Shut down a VM object, despite the
* presence of address map (or other) references
* to the vm_object.
*/
kern_return_t
-memory_object_destroy(
- register vm_object_t object,
+vm_object_destroy(
+ vm_object_t object,
kern_return_t reason)
{
- ipc_port_t old_object;
- pager_request_t old_pager_request;
-
-#ifdef lint
- reason++;
-#endif /* lint */
+ memory_object_t old_pager;
if (object == VM_OBJECT_NULL)
return(KERN_SUCCESS);
/*
- * Remove the port associations immediately.
+ * Remove the pager association immediately.
*
* This will prevent the memory manager from further
* meddling. [If it wanted to flush data or make
vm_object_cache_lock();
vm_object_lock(object);
- vm_object_remove(object);
object->can_persist = FALSE;
object->named = FALSE;
- vm_object_cache_unlock();
+ object->alive = FALSE;
/*
- * Rip out the ports from the vm_object now... this
- * will prevent new memory_object calls from succeeding.
+ * Rip out the pager from the vm_object now...
*/
- old_object = object->pager;
- old_pager_request = object->pager_request;
-
- object->pager = IP_NULL;
- object->pager_request = PAGER_REQUEST_NULL;
+ vm_object_remove(object);
+ old_pager = object->pager;
+ object->pager = MEMORY_OBJECT_NULL;
+ if (old_pager != MEMORY_OBJECT_NULL)
+ memory_object_control_disable(object->pager_request);
+ vm_object_cache_unlock();
/*
- * Wait for existing paging activity (that might
- * have the old ports) to subside.
+ * Wait for the existing paging activity (that got
+ * through before we nulled out the pager) to subside.
*/
vm_object_paging_wait(object, THREAD_UNINT);
vm_object_unlock(object);
/*
- * Shut down the ports now.
- *
- * [Paging operations may be proceeding concurrently --
- * they'll get the null values established above.]
+ * Terminate the object now.
*/
+ if (old_pager != MEMORY_OBJECT_NULL) {
+ vm_object_release_pager(old_pager);
+
+ /*
+ * JMM - Release the caller's reference. This assumes the
+ * caller had a reference to release, which is a big (but
+ * currently valid) assumption if this is driven from the
+ * vnode pager (it is holding a named reference when making
+ * this call)..
+ */
+ vm_object_deallocate(object);
- if (old_object != IP_NULL) {
- /* consumes our rights for object, control */
- memory_object_release(old_object, old_pager_request);
}
-
- /*
- * Lose the reference that was donated for this routine
- */
-
- vm_object_deallocate(object);
-
return(KERN_SUCCESS);
}
*
* The object must be locked.
*/
-void
-vm_object_deactivate_pages(
+static void
+vm_object_deactivate_all_pages(
register vm_object_t object)
{
register vm_page_t p;
}
}
+__private_extern__ void
+vm_object_deactivate_pages(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ boolean_t kill_page)
+{
+ vm_object_t orig_object;
+ int pages_moved = 0;
+ int pages_found = 0;
+
+ /*
+ * entered with object lock held, acquire a paging reference to
+ * prevent the memory_object and control ports from
+ * being destroyed.
+ */
+ orig_object = object;
+
+ for (;;) {
+ register vm_page_t m;
+ vm_object_offset_t toffset;
+ vm_object_size_t tsize;
+
+ vm_object_paging_begin(object);
+ vm_page_lock_queues();
+
+ for (tsize = size, toffset = offset; tsize; tsize -= PAGE_SIZE, toffset += PAGE_SIZE) {
+
+ if ((m = vm_page_lookup(object, toffset)) != VM_PAGE_NULL) {
+
+ pages_found++;
+
+ if ((m->wire_count == 0) && (!m->private) && (!m->gobbled) && (!m->busy)) {
+
+ m->reference = FALSE;
+ pmap_clear_reference(m->phys_addr);
+
+ if ((kill_page) && (object->internal)) {
+ m->precious = FALSE;
+ m->dirty = FALSE;
+ pmap_clear_modify(m->phys_addr);
+ vm_external_state_clr(object->existence_map, offset);
+ }
+ VM_PAGE_QUEUES_REMOVE(m);
+
+ queue_enter_first(&vm_page_queue_inactive, m, vm_page_t, pageq);
+
+ m->inactive = TRUE;
+ if (!m->fictitious)
+ vm_page_inactive_count++;
+
+ pages_moved++;
+ }
+ }
+ }
+ vm_page_unlock_queues();
+ vm_object_paging_end(object);
+
+ if (object->shadow) {
+ vm_object_t tmp_object;
+
+ kill_page = 0;
+
+ offset += object->shadow_offset;
+
+ tmp_object = object->shadow;
+ vm_object_lock(tmp_object);
+
+ if (object != orig_object)
+ vm_object_unlock(object);
+ object = tmp_object;
+ } else
+ break;
+ }
+ if (object != orig_object)
+ vm_object_unlock(object);
+}
/*
* Routine: vm_object_pmap_protect
* pmap.
*/
-void
+__private_extern__ void
vm_object_pmap_protect(
register vm_object_t object,
register vm_object_offset_t offset,
* an error, this parameter will contain the value
* VM_OBJECT_NULL.
*/
-kern_return_t
+__private_extern__ kern_return_t
vm_object_copy_slowly(
register vm_object_t src_object,
vm_object_offset_t src_offset,
VM_BEHAVIOR_SEQUENTIAL,
&prot, &_result_page, &top_page,
(int *)0,
- &error_code, FALSE, FALSE);
+ &error_code, FALSE, FALSE, NULL, 0);
switch(result) {
case VM_FAULT_SUCCESS:
*/
/*ARGSUSED*/
-boolean_t
+__private_extern__ boolean_t
vm_object_copy_quickly(
vm_object_t *_object, /* INOUT */
vm_object_offset_t offset, /* IN */
return(TRUE);
}
-int copy_call_count = 0;
-int copy_call_sleep_count = 0;
-int copy_call_restart_count = 0;
+static int copy_call_count = 0;
+static int copy_call_sleep_count = 0;
+static int copy_call_restart_count = 0;
/*
* Routine: vm_object_copy_call [internal]
* If the return value indicates an error, this parameter
* is not valid.
*/
-kern_return_t
+static kern_return_t
vm_object_copy_call(
vm_object_t src_object,
vm_object_offset_t src_offset,
return KERN_SUCCESS;
}
-int copy_delayed_lock_collisions = 0;
-int copy_delayed_max_collisions = 0;
-int copy_delayed_lock_contention = 0;
-int copy_delayed_protect_iterate = 0;
-int copy_delayed_protect_lookup = 0;
-int copy_delayed_protect_lookup_wait = 0;
+static int copy_delayed_lock_collisions = 0;
+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]
* This routine will not block waiting for user-generated
* events. It is not interruptible.
*/
-vm_object_t
+__private_extern__ vm_object_t
vm_object_copy_delayed(
vm_object_t src_object,
vm_object_offset_t src_offset,
* declared strategy. This operation may block,
* and may be interrupted.
*/
-kern_return_t
+__private_extern__ kern_return_t
vm_object_copy_strategically(
register vm_object_t src_object,
vm_object_offset_t src_offset,
*/
boolean_t vm_object_shadow_check = FALSE;
-boolean_t
+__private_extern__ boolean_t
vm_object_shadow(
vm_object_t *object, /* IN/OUT */
vm_object_offset_t *offset, /* IN/OUT */
/*
* The relationship between vm_object structures and
- * the memory_object ports requires careful synchronization.
+ * the memory_object requires careful synchronization.
*
- * All associations are created by vm_object_enter. All three
- * port fields are filled in, as follows:
- * pager: the memory_object port itself, supplied by
+ * All associations are created by memory_object_create_named
+ * for external pagers and vm_object_pager_create for internal
+ * objects as follows:
+ *
+ * pager: the memory_object itself, supplied by
* the user requesting a mapping (or the kernel,
* when initializing internal objects); the
* kernel simulates holding send rights by keeping
* a port reference;
+ *
* pager_request:
* the memory object control port,
* created by the kernel; the kernel holds
* receive (and ownership) rights to this
* port, but no other references.
- * All of the ports are referenced by their global names.
*
* When initialization is complete, the "initialized" field
* is asserted. Other mappings using a particular memory object,
* This is the normal case, and is done even
* though one of the other cases has already been
* done.
- * vm_object_destroy:
- * The memory_object port has been destroyed,
- * meaning that the kernel cannot flush dirty
- * pages or request new data or unlock existing
- * data.
* memory_object_destroy:
* The memory manager has requested that the
- * kernel relinquish rights to the memory object
- * port. [The memory manager may not want to
- * destroy the port, but may wish to refuse or
- * tear down existing memory mappings.]
+ * kernel relinquish references to the memory
+ * object. [The memory manager may not want to
+ * destroy the memory object, but may wish to
+ * refuse or tear down existing memory mappings.]
+ *
* Each routine that breaks an association must break all of
* them at once. At some later time, that routine must clear
- * the vm_object port fields and release the port rights.
+ * the pager field and release the memory object references.
* [Furthermore, each routine must cope with the simultaneous
* or previous operations of the others.]
*
* In addition to the lock on the object, the vm_object_cache_lock
- * governs the port associations. References gained through the
- * port association require use of the cache lock.
+ * governs the associations. References gained through the
+ * association require use of the cache lock.
*
- * Because the port fields may be cleared spontaneously, they
+ * Because the pager field may be cleared spontaneously, it
* cannot be used to determine whether a memory object has
* ever been associated with a particular vm_object. [This
* knowledge is important to the shadow object mechanism.]
* For this reason, an additional "created" attribute is
* provided.
*
- * During various paging operations, the port values found in the
- * vm_object must be valid. To prevent these port rights from being
- * released, and to prevent the port associations from changing
+ * During various paging operations, the pager reference found in the
+ * vm_object must be valid. To prevent this from being released,
* (other than being removed, i.e., made null), routines may use
* the vm_object_paging_begin/end routines [actually, macros].
* The implementation uses the "paging_in_progress" and "wanted" fields.
- * [Operations that alter the validity of the port values include the
+ * [Operations that alter the validity of the pager values include the
* termination routines and vm_object_collapse.]
*/
-#define IKOT_PAGER_LOOKUP_TYPE IKOT_PAGING_REQUEST
-
-vm_object_t
-vm_object_lookup(
- ipc_port_t port)
-{
- vm_object_t object;
-
-start_over:
- object = VM_OBJECT_NULL;
-
- if (IP_VALID(port)) {
- vm_object_cache_lock();
- ip_lock(port);
- if (ip_active(port) &&
- (ip_kotype(port) == IKOT_PAGER_LOOKUP_TYPE)) {
- object = (vm_object_t) port->ip_kobject;
- if (!vm_object_lock_try(object)) {
- /*
- * failed to acquire object lock. Drop the
- * other two locks and wait for it, then go
- * back and start over in case the port
- * associations changed in the interim.
- */
- ip_unlock(port);
- vm_object_cache_unlock();
- vm_object_lock(object);
- vm_object_unlock(object);
- goto start_over;
- }
-
- assert(object->alive);
-
- if((object->ref_count == 0) && (!object->terminating)){
- queue_remove(&vm_object_cached_list, object,
- vm_object_t, cached_list);
- vm_object_cached_count--;
- XPR(XPR_VM_OBJECT_CACHE,
- "vm_object_lookup: removing %X, head (%X, %X)\n",
- (integer_t)object,
- (integer_t)vm_object_cached_list.next,
- (integer_t)vm_object_cached_list.prev, 0,0);
- }
-
- object->ref_count++;
- vm_object_res_reference(object);
- vm_object_unlock(object);
- }
- ip_unlock(port);
- vm_object_cache_unlock();
- }
-
- return object;
-}
-
-
+#if 0
+/*
+ * Routine: vm_object_pager_dead
+ *
+ * Purpose:
+ * A port is being destroy, and the IPC kobject code
+ * can't tell if it represents a pager port or not.
+ * So this function is called each time it sees a port
+ * die.
+ * THIS IS HORRIBLY INEFFICIENT. We should only call
+ * this routine if we had requested a notification on
+ * the port.
+ */
-void
-vm_object_destroy(
+__private_extern__ void
+vm_object_pager_dead(
ipc_port_t pager)
{
vm_object_t object;
vm_object_hash_entry_t entry;
- pager_request_t old_pager_request;
/*
* Perform essentially the same operations as in vm_object_lookup,
assert(object->pager == pager);
/*
- * Remove the port associations.
+ * Remove the pager association.
*
* Note that the memory_object itself is dead, so
* we don't bother with it.
*/
- object->pager = IP_NULL;
- vm_object_remove(object);
-
- old_pager_request = object->pager_request;
-
- object->pager_request = PAGER_REQUEST_NULL;
+ object->pager = MEMORY_OBJECT_NULL;
vm_object_unlock(object);
vm_object_cache_unlock();
vm_object_pager_wakeup(pager);
/*
- * Clean up the port references. Note that there's no
+ * Release the pager reference. Note that there's no
* point in trying the memory_object_terminate call
- * because the memory_object itself is dead.
+ * because the memory_object itself is dead. Also
+ * release the memory_object_control reference, since
+ * the pager didn't do that either.
*/
- ipc_port_release_send(pager);
-
- if ((ipc_port_t)old_pager_request != IP_NULL)
- ipc_port_dealloc_kernel((ipc_port_t)old_pager_request);
+ memory_object_deallocate(pager);
+ memory_object_control_deallocate(object->pager_request);
+
/*
* Restart pending page requests
*/
vm_object_lock(object);
-
vm_object_abort_activity(object);
-
vm_object_unlock(object);
/*
vm_object_deallocate(object);
}
+#endif
/*
* Routine: vm_object_enter
*/
vm_object_t
vm_object_enter(
- ipc_port_t pager,
+ memory_object_t pager,
vm_object_size_t size,
boolean_t internal,
boolean_t init,
- boolean_t check_named)
+ boolean_t named)
{
register vm_object_t object;
vm_object_t new_object;
boolean_t must_init;
- ipc_port_t pager_request;
vm_object_hash_entry_t entry, new_entry;
-#ifdef MACH_BSD
-kern_return_t vnode_pager_init( ipc_port_t, ipc_port_t, vm_object_size_t);
-#endif
- if (!IP_VALID(pager))
+ if (pager == MEMORY_OBJECT_NULL)
return(vm_object_allocate(size));
new_object = VM_OBJECT_NULL;
*/
if (entry != VM_OBJECT_HASH_ENTRY_NULL) {
- if (entry->object != VM_OBJECT_NULL) {
- if(check_named) {
- if(entry->object->named) {
- vm_object_cache_unlock();
- return(entry->object);
- }
- }
+ if (entry->object != VM_OBJECT_NULL)
break;
- }
entry->waiting = TRUE;
assert_wait((event_t) pager, THREAD_UNINT);
vm_object_lock(object);
assert(object->pager_created);
assert(!internal || object->internal);
- if (check_named)
+ if (named) {
+ assert(!object->named);
object->named = TRUE;
+ }
if (object->ref_count == 0) {
XPR(XPR_VM_OBJECT_CACHE,
"vm_object_enter: removing %x from cache, head (%x, %x)\n",
vm_object_hash_entry_free(new_entry);
if (must_init) {
+ pager_request_t pager_request;
/*
* Allocate request port.
*/
- pager_request = ipc_port_alloc_kernel();
- assert (pager_request != IP_NULL);
- ipc_kobject_set(pager_request, (ipc_kobject_t) object,
- IKOT_PAGING_REQUEST);
+ pager_request = memory_object_control_allocate(object);
+ assert (pager_request != PAGER_REQUEST_NULL);
vm_object_lock(object);
/*
- * Copy the naked send right we were given.
+ * Copy the reference we were given.
*/
- pager = ipc_port_copy_send(pager);
- if (!IP_VALID(pager))
- panic("vm_object_enter: port died"); /* XXX */
-
+ memory_object_reference(pager);
object->pager_created = TRUE;
object->pager = pager;
object->internal = internal;
object->pager_request = pager_request;
object->pager_ready = FALSE;
- if (check_named)
- object->named = TRUE;
vm_object_unlock(object);
/*
* Let the pager know we're using it.
*/
-#ifdef MACH_BSD
- if(((rpc_subsystem_t)pager_mux_hash_lookup(pager)) ==
- ((rpc_subsystem_t) &vnode_pager_workaround)) {
- (void) vnode_pager_init(pager,
- object->pager_request,
- PAGE_SIZE);
- } else {
- (void) memory_object_init(pager,
- object->pager_request,
- PAGE_SIZE);
- }
-#else
- (void) memory_object_init(pager,
- object->pager_request,
- PAGE_SIZE);
-#endif
+ (void) memory_object_init(pager,
+ object->pager_request,
+ PAGE_SIZE);
vm_object_lock(object);
+ if (named)
+ object->named = TRUE;
if (internal) {
object->pager_ready = TRUE;
vm_object_wakeup(object, VM_OBJECT_EVENT_PAGER_READY);
vm_object_pager_create(
register vm_object_t object)
{
- ipc_port_t pager;
+ memory_object_t pager;
vm_object_hash_entry_t entry;
#if MACH_PAGEMAP
vm_object_size_t size;
#endif /* MACH_PAGEMAP */
/*
- * Create the pager ports, and associate them with this object.
+ * Create the [internal] pager, and associate it with this object.
*
- * We make the port association here so that vm_object_enter()
+ * We make the association here so that vm_object_enter()
* can look up the object to complete initializing it. No
* user will ever map this object.
*/
{
- ipc_port_t DMM;
+ memory_object_default_t dmm;
vm_size_t cluster_size;
- /* acquire a naked send right for the DMM */
- DMM = memory_manager_default_reference(&cluster_size);
+ /* acquire a reference for the default memory manager */
+ dmm = memory_manager_default_reference(&cluster_size);
assert(cluster_size >= PAGE_SIZE);
object->cluster_size = cluster_size; /* XXX ??? */
assert(object->temporary);
- /* consumes the naked send right for DMM */
- (void) memory_object_create(DMM, &pager, object->size);
- assert(IP_VALID(pager));
+ /* create our new memory object */
+ (void) memory_object_create(dmm, object->size, &pager);
+
+ memory_object_default_deallocate(dmm);
}
entry = vm_object_hash_entry_alloc(pager);
vm_object_cache_unlock();
/*
- * A naked send right was returned by
+ * A reference was returned by
* memory_object_create(), and it is
* copied by vm_object_enter().
*/
panic("vm_object_pager_create: mismatch");
/*
- * Drop the naked send right.
+ * Drop the reference we were passed.
*/
- ipc_port_release_send(pager);
+ memory_object_deallocate(pager);
vm_object_lock(object);
* Conditions:
* The object cache must be locked.
*/
-void
+__private_extern__ void
vm_object_remove(
vm_object_t object)
{
- ipc_port_t port;
+ memory_object_t pager;
+ pager_request_t pager_request;
- if ((port = object->pager) != IP_NULL) {
+ if ((pager = object->pager) != MEMORY_OBJECT_NULL) {
vm_object_hash_entry_t entry;
- entry = vm_object_hash_lookup(port, FALSE);
+ entry = vm_object_hash_lookup(pager, FALSE);
if (entry != VM_OBJECT_HASH_ENTRY_NULL)
entry->object = VM_OBJECT_NULL;
}
- if ((port = object->pager_request) != IP_NULL) {
- if (ip_kotype(port) == IKOT_PAGING_REQUEST)
- ipc_kobject_set(port, IKO_NULL, IKOT_NONE);
- else if (ip_kotype(port) != IKOT_NONE)
- panic("vm_object_remove: bad request port");
- }
}
/*
* Counts for normal collapses and bypasses.
* Debugging variables, to watch or disable collapse.
*/
-long object_collapses = 0;
-long object_bypasses = 0;
+static long object_collapses = 0;
+static long object_bypasses = 0;
-boolean_t vm_object_collapse_allowed = TRUE;
-boolean_t vm_object_bypass_allowed = TRUE;
+static boolean_t vm_object_collapse_allowed = TRUE;
+static boolean_t vm_object_bypass_allowed = TRUE;
+
+static int vm_external_discarded;
+static int vm_external_collapsed;
-int vm_external_discarded;
-int vm_external_collapsed;
/*
- * vm_object_do_collapse:
- *
- * Collapse an object with the object backing it.
- * Pages in the backing object are moved into the
- * parent, and the backing object is deallocated.
- *
- * Both objects and the cache are locked; the page
- * queues are unlocked.
+ * Routine: vm_object_do_collapse
+ * Purpose:
+ * Collapse an object with the object backing it.
+ * Pages in the backing object are moved into the
+ * parent, and the backing object is deallocated.
+ * Conditions:
+ * Both objects and the cache are locked; the page
+ * queues are unlocked.
*
*/
-void
+static void
vm_object_do_collapse(
vm_object_t object,
vm_object_t backing_object)
backing_offset = object->shadow_offset;
size = object->size;
-
/*
* Move all in-memory pages from backing_object
* to the parent. Pages that have been paged out
}
}
- assert(object->pager == IP_NULL || backing_object->pager == IP_NULL);
+ assert(object->pager == MEMORY_OBJECT_NULL ||
+ backing_object->pager == MEMORY_OBJECT_NULL);
- if (backing_object->pager != IP_NULL) {
+ if (backing_object->pager != MEMORY_OBJECT_NULL) {
vm_object_hash_entry_t entry;
/*
object->cluster_size = backing_object->cluster_size;
object->paging_offset =
backing_object->paging_offset + backing_offset;
- if (object->pager_request != IP_NULL) {
- ipc_kobject_set(object->pager_request,
- (ipc_kobject_t) object,
- IKOT_PAGING_REQUEST);
+ if (object->pager_request != PAGER_REQUEST_NULL) {
+ memory_object_control_collapse(object->pager_request,
+ object);
}
}
(backing_object->resident_page_count == 0) &&
(backing_object->paging_in_progress == 0));
- assert(backing_object->alive);
backing_object->alive = FALSE;
vm_object_unlock(backing_object);
object_collapses++;
}
-void
+static void
vm_object_do_bypass(
vm_object_t object,
vm_object_t backing_object)
object_bypasses++;
}
+
/*
* vm_object_collapse:
* Requires that the object be locked and the page queues be unlocked.
*
*/
-void
+__private_extern__ void
vm_object_collapse(
register vm_object_t object)
{
register vm_object_offset_t new_offset;
register vm_page_t p;
+ vm_offset_t current_offset;
+
if (! vm_object_collapse_allowed && ! vm_object_bypass_allowed) {
return;
}
* object (if the parent is the only reference to
* it) or (perhaps) remove the parent's reference
* to it.
- */
-
- /*
- * If there is exactly one reference to the backing
- * object, we may be able to collapse it into the parent.
*
- * XXXO (norma vm):
+ * If there is exactly one reference to the backing
+ * object, we may be able to collapse it into the
+ * parent.
*
* The backing object must not have a pager
* created for it, since collapsing an object
* into a backing_object dumps new pages into
* the backing_object that its pager doesn't
- * know about, and we've already declared pages.
- * This page dumping is deadly if other kernels
- * are shadowing this object; this is the
- * distributed equivalent of the ref_count == 1
- * condition.
- *
- * With some work, we could downgrade this
- * restriction to the backing object must not
- * be cachable, since when a temporary object
- * is uncachable we are allowed to do anything
- * to it. We would have to do something like
- * call declare_pages again, and we would have
- * to be prepared for the memory manager
- * disabling temporary termination, which right
- * now is a difficult race to deal with, since
- * the memory manager currently assumes that
- * termination is the only possible failure
- * for disabling temporary termination.
+ * know about.
*/
if (backing_object->ref_count == 1 &&
return;
}
+
/*
* If the backing object has a pager but no pagemap,
* then we cannot bypass it, because we don't know
return;
}
+ /*
+ * If the object has a pager but no pagemap,
+ * then we cannot bypass it, because we don't know
+ * what pages it has.
+ */
+ if (object->pager_created
+#if MACH_PAGEMAP
+ && (object->existence_map == VM_EXTERNAL_NULL)
+#endif /* MACH_PAGEMAP */
+ ) {
+ vm_object_unlock(backing_object);
+ return;
+ }
+
backing_offset = object->shadow_offset;
size = object->size;
* we must check examine its existence info
* as well.
*
- * XXX
- * Should have a check for a 'small' number
- * of pages here.
*/
- /*
- * First, check pages resident in the backing object.
- */
+ if(object->cow_hint >= size)
+ object->cow_hint = 0;
+ current_offset = object->cow_hint;
+ while(TRUE) {
+ if (vm_page_lookup(object,
+ (vm_object_offset_t)current_offset)
+ != VM_PAGE_NULL) {
+ current_offset+=PAGE_SIZE;
+ } else if ((object->pager_created) &&
+ (object->existence_map != NULL) &&
+ (vm_external_state_get(object->existence_map,
+ current_offset)
+ != VM_EXTERNAL_STATE_ABSENT)) {
+ current_offset+=PAGE_SIZE;
+ } else if (vm_page_lookup(backing_object,
+ (vm_object_offset_t)current_offset
+ + backing_offset)!= VM_PAGE_NULL) {
+ /* found a dependency */
+ object->cow_hint = current_offset;
+ vm_object_unlock(backing_object);
+ return;
+ } else if ((backing_object->pager_created) &&
+ (backing_object->existence_map != NULL) &&
+ (vm_external_state_get(
+ backing_object->existence_map,
+ current_offset + backing_offset)
+ != VM_EXTERNAL_STATE_ABSENT)) {
+ /* found a dependency */
+ object->cow_hint = current_offset;
+ vm_object_unlock(backing_object);
+ return;
+ } else {
+ current_offset+=PAGE_SIZE;
+ }
+ if(current_offset >= size) {
+ /* wrap at end of object */
+ current_offset = 0;
+ }
+ if(current_offset == object->cow_hint) {
+ /* we are free of shadow influence */
+ break;
+ }
+ }
+ /* reset the cow_hint for any objects deeper in the chain */
+ object->cow_hint = 0;
- queue_iterate(&backing_object->memq, p, vm_page_t, listq) {
-
- /*
- * If the parent has a page here, or if
- * this page falls outside the parent,
- * keep going.
- *
- * Otherwise, the backing_object must be
- * left in the chain.
- */
-
- new_offset = (p->offset - backing_offset);
- if (p->offset < backing_offset || new_offset >= size) {
- /*
- * Page falls outside of parent.
- * Keep going.
- */
-
- continue;
- }
-
- if ((vm_page_lookup(object, new_offset) == VM_PAGE_NULL)
-#if MACH_PAGEMAP
- &&
- (vm_external_state_get(object->existence_map,
- new_offset)
- != VM_EXTERNAL_STATE_EXISTS)
-#endif /* MACH_PAGEMAP */
- ) {
-
- /*
- * Page still needed.
- * Can't go any further.
- */
-
- vm_object_unlock(backing_object);
- return;
- }
- }
-
-#if MACH_PAGEMAP
- /*
- * Next, if backing object has been paged out,
- * we must check its existence info for pages
- * that the parent doesn't have.
- */
-
- if (backing_object->pager_created) {
- assert(backing_object->existence_map
- != VM_EXTERNAL_NULL);
- for (new_offset = 0; new_offset < object->size;
- new_offset += PAGE_SIZE_64) {
- vm_object_offset_t
- offset = new_offset + backing_offset;
-
- /*
- * If this page doesn't exist in
- * the backing object's existence
- * info, then continue.
- */
-
- if (vm_external_state_get(
- backing_object->existence_map,
- offset) == VM_EXTERNAL_STATE_ABSENT) {
- continue;
- }
-
- /*
- * If this page is neither resident
- * in the parent nor paged out to
- * the parent's pager, then we cannot
- * bypass the backing object.
- */
-
- if ((vm_page_lookup(object, new_offset) ==
- VM_PAGE_NULL) &&
- ((object->existence_map == VM_EXTERNAL_NULL)
- || (vm_external_state_get(
- object->existence_map, new_offset)
- == VM_EXTERNAL_STATE_ABSENT))) {
- vm_object_unlock(backing_object);
- return;
- }
- }
- }
-#else /* MACH_PAGEMAP */
- assert(! backing_object->pager_created);
-#endif /* MACH_PAGEMAP */
/*
* All interesting pages in the backing object
unsigned int vm_object_page_remove_lookup = 0;
unsigned int vm_object_page_remove_iterate = 0;
-void
+__private_extern__ void
vm_object_page_remove(
register vm_object_t object,
register vm_object_offset_t start,
}
}
+
/*
* Routine: vm_object_coalesce
* Function: Coalesces two objects backing up adjoining
* The object(s) must *not* be locked. The map must be locked
* to preserve the reference to the object(s).
*/
-int vm_object_coalesce_count = 0;
+static int vm_object_coalesce_count = 0;
-boolean_t
+__private_extern__ boolean_t
vm_object_coalesce(
register vm_object_t prev_object,
vm_object_t next_object,
}
vm_page_init(m, addr);
+ /* private normally requires lock_queues but since we */
+ /* are initializing the page, its not necessary here */
m->private = TRUE; /* don`t free page */
m->wire_count = 1;
vm_page_insert(m, object, offset);
{
extern db_indent;
- int count = 1;
+ int count = 0;
+ int orig_db_indent = db_indent;
- if (object == VM_OBJECT_NULL)
- return 0;
+ while (TRUE) {
+ if (object == VM_OBJECT_NULL) {
+ db_indent = orig_db_indent;
+ return count;
+ }
- iprintf("object 0x%x", object);
- printf(", shadow=0x%x", object->shadow);
- printf(", copy=0x%x", object->copy);
- printf(", pager=0x%x", object->pager);
- printf(", ref=%d\n", object->ref_count);
+ count += 1;
- db_indent += 2;
- if (object->shadow)
- count += vm_follow_object(object->shadow);
+ iprintf("object 0x%x", object);
+ printf(", shadow=0x%x", object->shadow);
+ printf(", copy=0x%x", object->copy);
+ printf(", pager=0x%x", object->pager);
+ printf(", ref=%d\n", object->ref_count);
+
+ db_indent += 2;
+ object = object->shadow;
+ }
- db_indent -= 2;
- return count;
}
/*
#endif /* MACH_KDB */
+kern_return_t
+vm_object_populate_with_private(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_offset_t phys_addr,
+ vm_size_t size)
+{
+ vm_offset_t base_addr;
+ vm_object_offset_t base_offset;
+
+
+ if(!object->private)
+ return KERN_FAILURE;
+
+ if((base_addr = trunc_page(phys_addr)) != phys_addr) {
+ return KERN_FAILURE;
+ }
+
+
+ vm_object_lock(object);
+ if(!object->phys_contiguous) {
+ vm_page_t m;
+ if((base_offset = trunc_page(offset)) != offset) {
+ vm_object_unlock(object);
+ return KERN_FAILURE;
+ }
+ base_offset += object->paging_offset;
+ while(size) {
+ m = vm_page_lookup(object, base_offset);
+ if(m != VM_PAGE_NULL) {
+ if(m->fictitious) {
+ vm_page_lock_queues();
+ m->fictitious = FALSE;
+ m->private = TRUE;
+ m->phys_addr = base_addr;
+ if(!m->busy) {
+ m->busy = TRUE;
+ }
+ if(!m->absent) {
+ m->absent = TRUE;
+ object->absent_count++;
+ }
+ m->list_req_pending = TRUE;
+ vm_page_unlock_queues();
+ } else if (m->phys_addr != base_addr) {
+ /* pmap call to clear old mapping */
+ pmap_page_protect(m->phys_addr,
+ VM_PROT_NONE);
+ m->phys_addr = base_addr;
+ }
+ } else {
+ while ((m = vm_page_grab_fictitious())
+ == VM_PAGE_NULL)
+ vm_page_more_fictitious();
+ vm_page_lock_queues();
+ m->fictitious = FALSE;
+ m->private = TRUE;
+ m->phys_addr = base_addr;
+ m->list_req_pending = TRUE;
+ m->absent = TRUE;
+ m->unusual = TRUE;
+ object->absent_count++;
+ vm_page_unlock_queues();
+ vm_page_insert(m, object, base_offset);
+ }
+ base_addr += PAGE_SIZE;
+ base_offset += PAGE_SIZE;
+ size -= PAGE_SIZE;
+ }
+ } else {
+ /* NOTE: we should check the original settings here */
+ /* if we have a size > zero a pmap call should be made */
+ /* to disable the range */
+
+ /* pmap_? */
+
+ /* shadows on contiguous memory are not allowed */
+ /* we therefore can use the offset field */
+ object->shadow_offset = (vm_object_offset_t)phys_addr;
+ object->size = size;
+ }
+ vm_object_unlock(object);
+ return KERN_SUCCESS;
+}
+
/*
* memory_object_free_from_cache:
*
* which are backed by the pager identified by the caller, (pager_id).
* Remove up to "count" objects, if there are that may available
* in the cache.
+ *
* Walk the list at most once, return the number of vm_objects
* actually freed.
- *
*/
-kern_return_t
+__private_extern__ kern_return_t
memory_object_free_from_cache(
host_t host,
- int pager_id,
+ int *pager_id,
int *count)
{
queue_iterate(&vm_object_cached_list, object,
vm_object_t, cached_list) {
- if (pager_id == (int) pager_mux_hash_lookup(
- (ipc_port_t)object->pager)) {
+ if (object->pager && (pager_id == object->pager->pager)) {
vm_object_lock(object);
queue_remove(&vm_object_cached_list, object,
vm_object_t, cached_list);
/*
* Since this object is in the cache, we know
- * that it is initialized and has no references.
- * Take a reference to avoid recursive
- * deallocations.
+ * that it is initialized and has only a pager's
+ * (implicit) reference. Take a reference to avoid
+ * recursive deallocations.
*/
assert(object->pager_initialized);
return KERN_SUCCESS;
}
-/*
- * memory_object_remove_cached_object:
- *
- * Check for the existance of a memory object represented by the
- * supplied port. If one exists and it is not in use, remove the
- * memory object from the vm_object cache.
- * If the memory object is in use, turn off the the "can_persist"
- * property so that it will not go in the cache when the last user
- * gives it up.
- *
- */
+
kern_return_t
-memory_object_remove_cached_object(
- ipc_port_t port)
+memory_object_create_named(
+ memory_object_t pager,
+ memory_object_offset_t size,
+ memory_object_control_t *control)
{
- vm_object_t object;
- vm_object_t shadow;
+ vm_object_t object;
+ vm_object_hash_entry_t entry;
-repeat_lock_acquire:
- object = VM_OBJECT_NULL;
+ *control = MEMORY_OBJECT_CONTROL_NULL;
+ if (pager == MEMORY_OBJECT_NULL)
+ return KERN_INVALID_ARGUMENT;
- if (IP_VALID(port)) {
- vm_object_cache_lock();
- ip_lock(port);
- if (ip_active(port) &&
- (ip_kotype(port) == IKOT_PAGER_LOOKUP_TYPE)) {
- object = (vm_object_t) port->ip_kobject;
- if (!vm_object_lock_try(object)) {
- /*
- * failed to acquire object lock. Drop the
- * other two locks and wait for it, then go
- * back and start over in case the port
- * associations changed in the interim.
- */
- ip_unlock(port);
- vm_object_cache_unlock();
- vm_object_lock(object);
- vm_object_unlock(object);
- goto repeat_lock_acquire;
- }
+ vm_object_cache_lock();
+ entry = vm_object_hash_lookup(pager, FALSE);
+ if ((entry != VM_OBJECT_HASH_ENTRY_NULL) &&
+ (entry->object != VM_OBJECT_NULL)) {
+ if (entry->object->named == TRUE)
+ panic("memory_object_create_named: caller already holds the right"); }
- if(object->terminating) {
- ip_unlock(port);
- vm_object_unlock(object);
- vm_object_cache_unlock();
- return KERN_RIGHT_EXISTS;
- }
+ vm_object_cache_unlock();
+ if ((object = vm_object_enter(pager, size, FALSE, FALSE, TRUE))
+ == VM_OBJECT_NULL) {
+ return(KERN_INVALID_OBJECT);
+ }
+
+ /* wait for object (if any) to be ready */
+ if (object != VM_OBJECT_NULL) {
+ vm_object_lock(object);
+ object->named = TRUE;
+ while (!object->pager_ready) {
+ vm_object_wait(object,
+ VM_OBJECT_EVENT_PAGER_READY,
+ FALSE);
+ vm_object_lock(object);
+ }
+ *control = object->pager_request;
+ vm_object_unlock(object);
+ }
+ return (KERN_SUCCESS);
+}
- assert(object->alive);
- ip_unlock(port);
- if (object->ref_count == 0) {
- queue_remove(&vm_object_cached_list, object,
- vm_object_t, cached_list);
- vm_object_cached_count--;
- object->ref_count++;
- /*
- * Terminate the object.
- * If the object had a shadow, we let
- * vm_object_deallocate deallocate it.
- * "pageout" objects have a shadow, but
- * maintain a "paging reference" rather
- * than a normal reference.
- * (We are careful here to limit
- * recursion.)
- */
- shadow = object->pageout?
- VM_OBJECT_NULL:object->shadow;
- /* will do the vm_object_cache_unlock */
- if((vm_object_terminate(object)
- == KERN_SUCCESS)
- && (shadow != VM_OBJECT_NULL)) {
- /* will lock and unlock cache_lock */
- vm_object_deallocate(shadow);
- }
- }
- else {
- /*
- * We cannot free object but we can
- * make sure it doesn't go into the
- * cache when it is no longer in
- * use.
- */
- object->can_persist = FALSE;
+/*
+ * Routine: memory_object_recover_named [user interface]
+ * Purpose:
+ * Attempt to recover a named reference for a VM object.
+ * VM will verify that the object has not already started
+ * down the termination path, and if it has, will optionally
+ * wait for that to finish.
+ * Returns:
+ * KERN_SUCCESS - we recovered a named reference on the object
+ * KERN_FAILURE - we could not recover a reference (object dead)
+ * KERN_INVALID_ARGUMENT - bad memory object control
+ */
+kern_return_t
+memory_object_recover_named(
+ memory_object_control_t control,
+ boolean_t wait_on_terminating)
+{
+ vm_object_t object;
- vm_object_unlock(object);
- vm_object_cache_unlock();
- return KERN_RIGHT_EXISTS;
- }
+ vm_object_cache_lock();
+ object = memory_object_control_to_vm_object(control);
+ if (object == VM_OBJECT_NULL) {
+ vm_object_cache_unlock();
+ return (KERN_INVALID_ARGUMENT);
+ }
+restart:
+ vm_object_lock(object);
- }
- else {
- ip_unlock(port);
- vm_object_cache_unlock();
- }
- } else {
- return KERN_INVALID_ARGUMENT;
+ if (object->terminating && wait_on_terminating) {
+ vm_object_cache_unlock();
+ vm_object_wait(object,
+ VM_OBJECT_EVENT_PAGING_IN_PROGRESS,
+ THREAD_UNINT);
+ vm_object_cache_lock();
+ goto restart;
+ }
+
+ if (!object->alive) {
+ vm_object_cache_unlock();
+ vm_object_unlock(object);
+ return KERN_FAILURE;
}
+ if (object->named == TRUE) {
+ vm_object_cache_unlock();
+ vm_object_unlock(object);
+ return KERN_SUCCESS;
+ }
- return KERN_SUCCESS;
+ if((object->ref_count == 0) && (!object->terminating)){
+ queue_remove(&vm_object_cached_list, object,
+ vm_object_t, cached_list);
+ vm_object_cached_count--;
+ XPR(XPR_VM_OBJECT_CACHE,
+ "memory_object_recover_named: removing %X, head (%X, %X)\n",
+ (integer_t)object,
+ (integer_t)vm_object_cached_list.next,
+ (integer_t)vm_object_cached_list.prev, 0,0);
+ }
+
+ vm_object_cache_unlock();
+
+ object->named = TRUE;
+ object->ref_count++;
+ vm_object_res_reference(object);
+ while (!object->pager_ready) {
+ vm_object_wait(object,
+ VM_OBJECT_EVENT_PAGER_READY,
+ FALSE);
+ vm_object_lock(object);
+ }
+ vm_object_unlock(object);
+ return (KERN_SUCCESS);
}
-kern_return_t
-memory_object_create_named(
- ipc_port_t port,
- vm_object_size_t size,
- vm_object_t *object_ptr)
+
+/*
+ * vm_object_release_name:
+ *
+ * Enforces name semantic on memory_object reference count decrement
+ * This routine should not be called unless the caller holds a name
+ * reference gained through the memory_object_create_named.
+ *
+ * If the TERMINATE_IDLE flag is set, the call will return if the
+ * reference count is not 1. i.e. idle with the only remaining reference
+ * being the name.
+ * If the decision is made to proceed the name field flag is set to
+ * false and the reference count is decremented. If the RESPECT_CACHE
+ * flag is set and the reference count has gone to zero, the
+ * memory_object is checked to see if it is cacheable otherwise when
+ * the reference count is zero, it is simply terminated.
+ */
+
+__private_extern__ kern_return_t
+vm_object_release_name(
+ vm_object_t object,
+ int flags)
{
- vm_object_t object;
- vm_object_hash_entry_t entry;
+ vm_object_t shadow;
+ boolean_t original_object = TRUE;
- *object_ptr = (vm_object_t)NULL;
- if (IP_VALID(port)) {
+ while (object != VM_OBJECT_NULL) {
+ /*
+ * The cache holds a reference (uncounted) to
+ * the object. We must locke it before removing
+ * the object.
+ *
+ */
+
vm_object_cache_lock();
- entry = vm_object_hash_lookup(port, FALSE);
- if ((entry != VM_OBJECT_HASH_ENTRY_NULL) &&
- (entry->object != VM_OBJECT_NULL)) {
- if (entry->object->named == TRUE)
- panic("memory_object_create_named: caller already holds the right");
+ vm_object_lock(object);
+ assert(object->alive);
+ if(original_object)
+ assert(object->named);
+ assert(object->ref_count > 0);
+
+ /*
+ * We have to wait for initialization before
+ * destroying or caching the object.
+ */
+
+ if (object->pager_created && !object->pager_initialized) {
+ assert(!object->can_persist);
+ vm_object_assert_wait(object,
+ VM_OBJECT_EVENT_INITIALIZED,
+ THREAD_UNINT);
+ vm_object_unlock(object);
+ vm_object_cache_unlock();
+ thread_block((void (*)(void)) 0);
+ continue;
}
- vm_object_cache_unlock();
- if ((object = vm_object_enter(port, size, FALSE, FALSE, TRUE))
- == VM_OBJECT_NULL)
- return(KERN_INVALID_OBJECT);
-
- /* wait for object (if any) to be ready */
- if (object != VM_OBJECT_NULL) {
- vm_object_lock(object);
- object->named = TRUE;
- while (!object->pager_ready) {
- vm_object_wait(object,
- VM_OBJECT_EVENT_PAGER_READY,
- FALSE);
- vm_object_lock(object);
+ if (((object->ref_count > 1)
+ && (flags & MEMORY_OBJECT_TERMINATE_IDLE))
+ || (object->terminating)) {
+ vm_object_unlock(object);
+ vm_object_cache_unlock();
+ return KERN_FAILURE;
+ } else {
+ if (flags & MEMORY_OBJECT_RELEASE_NO_OP) {
+ vm_object_unlock(object);
+ vm_object_cache_unlock();
+ return KERN_SUCCESS;
}
+ }
+
+ if ((flags & MEMORY_OBJECT_RESPECT_CACHE) &&
+ (object->ref_count == 1)) {
+ if(original_object)
+ object->named = FALSE;
vm_object_unlock(object);
+ vm_object_cache_unlock();
+ /* let vm_object_deallocate push this thing into */
+ /* the cache, if that it is where it is bound */
+ vm_object_deallocate(object);
+ return KERN_SUCCESS;
+ }
+ VM_OBJ_RES_DECR(object);
+ shadow = object->pageout?VM_OBJECT_NULL:object->shadow;
+ if(object->ref_count == 1) {
+ if(vm_object_terminate(object) != KERN_SUCCESS) {
+ if(original_object) {
+ return KERN_FAILURE;
+ } else {
+ return KERN_SUCCESS;
+ }
+ }
+ if (shadow != VM_OBJECT_NULL) {
+ original_object = FALSE;
+ object = shadow;
+ continue;
+ }
+ return KERN_SUCCESS;
+ } else {
+ object->ref_count--;
+ assert(object->ref_count > 0);
+ if(original_object)
+ object->named = FALSE;
+ vm_object_unlock(object);
+ vm_object_cache_unlock();
+ return KERN_SUCCESS;
}
- *object_ptr = object;
- return (KERN_SUCCESS);
- } else {
- return (KERN_INVALID_ARGUMENT);
}
}
-kern_return_t
-memory_object_recover_named(
- ipc_port_t pager,
- boolean_t wait_on_terminating,
- vm_object_t *object_ptr)
+
+__private_extern__ kern_return_t
+vm_object_lock_request(
+ vm_object_t object,
+ vm_object_offset_t offset,
+ vm_object_size_t size,
+ memory_object_return_t should_return,
+ int flags,
+ vm_prot_t prot)
{
- vm_object_t object;
- vm_object_hash_entry_t entry;
+ vm_object_offset_t original_offset = offset;
+ boolean_t should_flush=flags & MEMORY_OBJECT_DATA_FLUSH;
- *object_ptr = (vm_object_t)NULL;
-lookup_entry:
- if (IP_VALID(pager)) {
+ XPR(XPR_MEMORY_OBJECT,
+ "vm_o_lock_request, obj 0x%X off 0x%X size 0x%X flags %X prot %X\n",
+ (integer_t)object, offset, size,
+ (((should_return&1)<<1)|should_flush), prot);
- vm_object_cache_lock();
- entry = vm_object_hash_lookup(pager, FALSE);
- if ((entry != VM_OBJECT_HASH_ENTRY_NULL) &&
- (entry->object != VM_OBJECT_NULL)) {
- if (entry->object->named == TRUE)
- panic("memory_object_recover_named: caller already holds the right");
- object = entry->object;
- vm_object_lock(object);
- vm_object_cache_unlock();
- if (object->terminating && wait_on_terminating) {
- vm_object_wait(object,
- VM_OBJECT_EVENT_PAGING_IN_PROGRESS,
- THREAD_UNINT);
- vm_object_unlock(object);
- goto lookup_entry;
- }
- } else {
- vm_object_cache_unlock();
- return KERN_FAILURE;
- }
+ /*
+ * Check for bogus arguments.
+ */
+ if (object == VM_OBJECT_NULL)
+ return (KERN_INVALID_ARGUMENT);
- if((object->ref_count == 0) && (!object->terminating)){
- queue_remove(&vm_object_cached_list, object,
- vm_object_t, cached_list);
- vm_object_cached_count--;
- XPR(XPR_VM_OBJECT_CACHE,
- "memory_object_recover_named: removing %X, head (%X, %X)\n",
- (integer_t)object,
- (integer_t)vm_object_cached_list.next,
- (integer_t)vm_object_cached_list.prev, 0,0);
- }
+ if ((prot & ~VM_PROT_ALL) != 0 && prot != VM_PROT_NO_CHANGE)
+ return (KERN_INVALID_ARGUMENT);
- object->named = TRUE;
- object->ref_count++;
- vm_object_res_reference(object);
- while (!object->pager_ready) {
- vm_object_wait(object,
- VM_OBJECT_EVENT_PAGER_READY,
- FALSE);
- vm_object_lock(object);
- }
+ size = round_page(size);
+
+ /*
+ * Lock the object, and acquire a paging reference to
+ * prevent the memory_object reference from being released.
+ */
+ vm_object_lock(object);
+ vm_object_paging_begin(object);
+ offset -= object->paging_offset;
+
+ (void)vm_object_update(object,
+ offset, size, should_return, flags, prot);
+
+ vm_object_paging_end(object);
+ vm_object_unlock(object);
+
+ return (KERN_SUCCESS);
+}
+
+
+
+#if TASK_SWAPPER
+/*
+ * vm_object_res_deallocate
+ *
+ * (recursively) decrement residence counts on vm objects and their shadows.
+ * Called from vm_object_deallocate and when swapping out an object.
+ *
+ * The object is locked, and remains locked throughout the function,
+ * even as we iterate down the shadow chain. Locks on intermediate objects
+ * will be dropped, but not the original object.
+ *
+ * NOTE: this function used to use recursion, rather than iteration.
+ */
+
+__private_extern__ void
+vm_object_res_deallocate(
+ vm_object_t object)
+{
+ vm_object_t orig_object = object;
+ /*
+ * Object is locked so it can be called directly
+ * from vm_object_deallocate. Original object is never
+ * unlocked.
+ */
+ assert(object->res_count > 0);
+ while (--object->res_count == 0) {
+ assert(object->ref_count >= object->res_count);
+ vm_object_deactivate_all_pages(object);
+ /* iterate on shadow, if present */
+ if (object->shadow != VM_OBJECT_NULL) {
+ vm_object_t tmp_object = object->shadow;
+ vm_object_lock(tmp_object);
+ if (object != orig_object)
+ vm_object_unlock(object);
+ object = tmp_object;
+ assert(object->res_count > 0);
+ } else
+ break;
+ }
+ if (object != orig_object)
vm_object_unlock(object);
- *object_ptr = object;
- return (KERN_SUCCESS);
- } else {
- return (KERN_INVALID_ARGUMENT);
+}
+
+/*
+ * vm_object_res_reference
+ *
+ * Internal function to increment residence count on a vm object
+ * and its shadows. It is called only from vm_object_reference, and
+ * when swapping in a vm object, via vm_map_swap.
+ *
+ * The object is locked, and remains locked throughout the function,
+ * even as we iterate down the shadow chain. Locks on intermediate objects
+ * will be dropped, but not the original object.
+ *
+ * NOTE: this function used to use recursion, rather than iteration.
+ */
+
+__private_extern__ void
+vm_object_res_reference(
+ vm_object_t object)
+{
+ vm_object_t orig_object = object;
+ /*
+ * Object is locked, so this can be called directly
+ * from vm_object_reference. This lock is never released.
+ */
+ while ((++object->res_count == 1) &&
+ (object->shadow != VM_OBJECT_NULL)) {
+ vm_object_t tmp_object = object->shadow;
+
+ assert(object->ref_count >= object->res_count);
+ vm_object_lock(tmp_object);
+ if (object != orig_object)
+ vm_object_unlock(object);
+ object = tmp_object;
}
+ if (object != orig_object)
+ vm_object_unlock(object);
+ assert(orig_object->ref_count >= orig_object->res_count);
}
+#endif /* TASK_SWAPPER */
+
+/*
+ * vm_object_reference:
+ *
+ * Gets another reference to the given object.
+ */
+#ifdef vm_object_reference
+#undef vm_object_reference
+#endif
+__private_extern__ void
+vm_object_reference(
+ register vm_object_t object)
+{
+ if (object == VM_OBJECT_NULL)
+ return;
+
+ vm_object_lock(object);
+ assert(object->ref_count > 0);
+ vm_object_reference_locked(object);
+ vm_object_unlock(object);
+}
+
#ifdef MACH_BSD
/*
* Scale the vm_object_cache
projects / apple / xnu.git / blobdiff