]> git.saurik.com Git - apple/xnu.git/blobdiff - osfmk/vm/vm_object.c
xnu-3789.31.2.tar.gz
[apple/xnu.git] / osfmk / vm / vm_object.c
index a16857ec00750e91161bdcf31d56b25669ad1ed4..72b525fdd76d7b5f9cc6ee82f2242c58a7ce43aa 100644 (file)
@@ -79,7 +79,6 @@
 
 #include <kern/kern_types.h>
 #include <kern/assert.h>
-#include <kern/lock.h>
 #include <kern/queue.h>
 #include <kern/xpr.h>
 #include <kern/kalloc.h>
@@ -88,6 +87,7 @@
 #include <kern/host_statistics.h>
 #include <kern/processor.h>
 #include <kern/misc_protos.h>
+#include <kern/policy_internal.h>
 
 #include <vm/memory_object.h>
 #include <vm/vm_compressor_pager.h>
 
 #include <vm/vm_compressor.h>
 
+#if CONFIG_PHANTOM_CACHE
+#include <vm/vm_phantom_cache.h>
+#endif
+
+boolean_t vm_object_collapse_compressor_allowed = TRUE;
+
+struct vm_counters vm_counters;
+
+#if VM_OBJECT_TRACKING
+boolean_t vm_object_tracking_inited = FALSE;
+btlog_t *vm_object_tracking_btlog;
+
+void
+vm_object_tracking_init(void)
+{
+       int vm_object_tracking;
+
+       vm_object_tracking = 1;
+       PE_parse_boot_argn("vm_object_tracking", &vm_object_tracking, 
+                          sizeof (vm_object_tracking));
+
+       if (vm_object_tracking) {
+               vm_object_tracking_btlog = btlog_create(
+                       VM_OBJECT_TRACKING_NUM_RECORDS,
+                       VM_OBJECT_TRACKING_BTDEPTH,
+                       TRUE /* caller_will_remove_entries_for_element? */);
+               assert(vm_object_tracking_btlog);
+               vm_object_tracking_inited = TRUE;
+       }
+}
+#endif /* VM_OBJECT_TRACKING */
+
 /*
  *     Virtual memory objects maintain the actual data
  *     associated with allocated virtual memory.  A given
@@ -205,10 +237,10 @@ 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.
  */
-static struct vm_object                        kernel_object_store;
-vm_object_t                                            kernel_object;
+static struct vm_object                        kernel_object_store __attribute__((aligned(VM_PACKED_POINTER_ALIGNMENT)));
+vm_object_t                            kernel_object;
 
-static struct vm_object                        compressor_object_store;
+static struct vm_object                        compressor_object_store __attribute__((aligned(VM_PACKED_POINTER_ALIGNMENT)));
 vm_object_t                            compressor_object = &compressor_object_store;
 
 /*
@@ -217,7 +249,7 @@ vm_object_t                         compressor_object = &compressor_object_store;
  *     is exported by the vm_map module.  The storage is declared
  *     here because it must be initialized here.
  */
-static struct vm_object                        vm_submap_object_store;
+static struct vm_object                        vm_submap_object_store __attribute__((aligned(VM_PACKED_POINTER_ALIGNMENT)));
 
 /*
  *     Virtual memory objects are initialized from
@@ -349,6 +381,35 @@ unsigned int vm_object_reap_count_async = 0;
 #define vm_object_reaper_unlock()      \
                lck_mtx_unlock(&vm_object_reaper_lock_data)
 
+#if CONFIG_IOSCHED
+/* I/O Re-prioritization request list */
+queue_head_t   io_reprioritize_list;
+lck_spin_t     io_reprioritize_list_lock;
+
+#define IO_REPRIORITIZE_LIST_LOCK()    \
+               lck_spin_lock(&io_reprioritize_list_lock)
+#define IO_REPRIORITIZE_LIST_UNLOCK()  \
+               lck_spin_unlock(&io_reprioritize_list_lock)
+
+#define MAX_IO_REPRIORITIZE_REQS       8192
+zone_t                 io_reprioritize_req_zone;
+
+/* I/O Re-prioritization thread */
+int io_reprioritize_wakeup = 0;
+static void io_reprioritize_thread(void *param __unused, wait_result_t wr __unused);
+
+#define IO_REPRIO_THREAD_WAKEUP()      thread_wakeup((event_t)&io_reprioritize_wakeup)
+#define IO_REPRIO_THREAD_CONTINUATION()                                \
+{                                                              \
+       assert_wait(&io_reprioritize_wakeup, THREAD_UNINT);     \
+       thread_block(io_reprioritize_thread);                   \
+}
+
+void vm_page_request_reprioritize(vm_object_t, uint64_t, uint32_t, int);
+void vm_page_handle_prio_inversion(vm_object_t, vm_page_t);
+void vm_decmp_upl_reprioritize(upl_t, int);
+#endif
+
 #if 0
 #undef KERNEL_DEBUG
 #define KERNEL_DEBUG KERNEL_DEBUG_CONSTANT
@@ -415,12 +476,26 @@ vm_object_hash_insert(
 {
        queue_t         bucket;
 
+       assert(vm_object_hash_lookup(entry->pager, FALSE) == NULL);
+
        bucket = &vm_object_hashtable[vm_object_hash(entry->pager)];
 
        queue_enter(bucket, entry, vm_object_hash_entry_t, hash_link);
 
+       if (object->hashed) {
+               /*
+                * "hashed" was pre-set on this (new) object to avoid
+                * locking issues in vm_object_enter() (can't attempt to
+                * grab the object lock while holding the hash lock as
+                * a spinlock), so no need to set it here (and no need to
+                * hold the object's lock).
+                */
+       } else {
+               vm_object_lock_assert_exclusive(object);
+               object->hashed = TRUE;
+       }
+
        entry->object = object;
-       object->hashed = TRUE;
 }
 
 static vm_object_hash_entry_t
@@ -460,20 +535,34 @@ _vm_object_allocate(
                object, size, 0,0,0);
 
        *object = vm_object_template;
-       queue_init(&object->memq);
+       vm_page_queue_init(&object->memq);
        queue_init(&object->msr_q);
-#if UPL_DEBUG
+#if UPL_DEBUG || CONFIG_IOSCHED
        queue_init(&object->uplq);
-#endif /* UPL_DEBUG */
+#endif
        vm_object_lock_init(object);
        object->vo_size = size;
+
+#if VM_OBJECT_TRACKING_OP_CREATED
+       if (vm_object_tracking_inited) {
+               void    *bt[VM_OBJECT_TRACKING_BTDEPTH];
+               int     numsaved = 0;
+
+               numsaved = OSBacktrace(bt, VM_OBJECT_TRACKING_BTDEPTH);
+               btlog_add_entry(vm_object_tracking_btlog,
+                               object,
+                               VM_OBJECT_TRACKING_OP_CREATED,
+                               bt,
+                               numsaved);
+       }
+#endif /* VM_OBJECT_TRACKING_OP_CREATED */
 }
 
 __private_extern__ vm_object_t
 vm_object_allocate(
        vm_object_size_t        size)
 {
-       register vm_object_t object;
+       vm_object_t object;
 
        object = (vm_object_t) zalloc(vm_object_zone);
        
@@ -501,12 +590,15 @@ lck_attr_t                compressor_object_lck_attr;
 __private_extern__ void
 vm_object_bootstrap(void)
 {
-       register int    i;
+       int     i;
+       vm_size_t       vm_object_size;
 
-       vm_object_zone = zinit((vm_size_t) sizeof(struct vm_object),
-                               round_page(512*1024),
-                               round_page(12*1024),
-                               "vm objects");
+       vm_object_size = (sizeof(struct vm_object) + (VM_PACKED_POINTER_ALIGNMENT-1)) & ~(VM_PACKED_POINTER_ALIGNMENT - 1);
+
+       vm_object_zone = zinit(vm_object_size,
+                              round_page(512*1024),
+                              round_page(12*1024),
+                              "vm objects");
        zone_change(vm_object_zone, Z_CALLERACCT, FALSE); /* don't charge caller */
        zone_change(vm_object_zone, Z_NOENCRYPT, TRUE);
 
@@ -549,8 +641,10 @@ vm_object_bootstrap(void)
         */
 
        /* memq; Lock; init after allocation */
-       vm_object_template.memq.prev = NULL;
-       vm_object_template.memq.next = NULL;
+       
+
+       vm_object_template.memq.prev = 0;
+       vm_object_template.memq.next = 0;
 #if 0
        /*
         * We can't call vm_object_lock_init() here because that will
@@ -560,6 +654,9 @@ vm_object_bootstrap(void)
         * the vm_object_template.
         */
        vm_object_lock_init(&vm_object_template);
+#endif
+#if DEVELOPMENT || DEBUG
+       vm_object_template.Lock_owner = 0;
 #endif
        vm_object_template.vo_size = 0;
        vm_object_template.memq_hint = VM_PAGE_NULL;
@@ -578,6 +675,9 @@ vm_object_bootstrap(void)
        vm_object_template.pager_control = MEMORY_OBJECT_CONTROL_NULL;
        vm_object_template.copy_strategy = MEMORY_OBJECT_COPY_SYMMETRIC;
        vm_object_template.paging_in_progress = 0;
+#if __LP64__
+       vm_object_template.__object1_unused_bits = 0;
+#endif /* __LP64__ */
        vm_object_template.activity_in_progress = 0;
 
        /* Begin bitfields */
@@ -614,10 +714,9 @@ vm_object_bootstrap(void)
        vm_object_template.pages_created = 0;
        vm_object_template.pages_used = 0;
        vm_object_template.scan_collisions = 0;
-
-#if    MACH_PAGEMAP
-       vm_object_template.existence_map = VM_EXTERNAL_NULL;
-#endif /* MACH_PAGEMAP */
+#if CONFIG_PHANTOM_CACHE
+       vm_object_template.phantom_object_id = 0;
+#endif
        vm_object_template.cow_hint = ~(vm_offset_t)0;
 #if    MACH_ASSERT
        vm_object_template.paging_object = VM_OBJECT_NULL;
@@ -631,12 +730,13 @@ vm_object_bootstrap(void)
        vm_object_template.hashed = FALSE;
        vm_object_template.transposed = FALSE;
        vm_object_template.mapping_in_progress = FALSE;
+       vm_object_template.phantom_isssd = FALSE;
        vm_object_template.volatile_empty = FALSE;
        vm_object_template.volatile_fault = FALSE;
        vm_object_template.all_reusable = FALSE;
        vm_object_template.blocked_access = FALSE;
        vm_object_template.__object2_unused_bits = 0;
-#if UPL_DEBUG
+#if CONFIG_IOSCHED || UPL_DEBUG
        vm_object_template.uplq.prev = NULL;
        vm_object_template.uplq.next = NULL;
 #endif /* UPL_DEBUG */
@@ -645,14 +745,33 @@ vm_object_bootstrap(void)
              sizeof (vm_object_template.pip_holders));
 #endif /* VM_PIP_DEBUG */
 
-       vm_object_template.objq.next=NULL;
-       vm_object_template.objq.prev=NULL;
+       vm_object_template.objq.next = NULL;
+       vm_object_template.objq.prev = NULL;
 
        vm_object_template.purgeable_queue_type = PURGEABLE_Q_TYPE_MAX;
        vm_object_template.purgeable_queue_group = 0;
 
        vm_object_template.vo_cache_ts = 0;
+
+       vm_object_template.wire_tag = VM_KERN_MEMORY_NONE;
+
+       vm_object_template.io_tracking = FALSE;
+
+#if CONFIG_SECLUDED_MEMORY
+       vm_object_template.eligible_for_secluded = FALSE;
+       vm_object_template.can_grab_secluded = FALSE;
+#else /* CONFIG_SECLUDED_MEMORY */
+       vm_object_template.__object3_unused_bits = 0;
+#endif /* CONFIG_SECLUDED_MEMORY */
        
+#if DEBUG
+       bzero(&vm_object_template.purgeable_owner_bt[0],
+             sizeof (vm_object_template.purgeable_owner_bt));
+       vm_object_template.vo_purgeable_volatilizer = NULL;
+       bzero(&vm_object_template.purgeable_volatilizer_bt[0],
+             sizeof (vm_object_template.purgeable_volatilizer_bt));
+#endif /* DEBUG */
+
        /*
         *      Initialize the "kernel object"
         */
@@ -664,16 +783,11 @@ vm_object_bootstrap(void)
  *     VM_MAX_KERNEL_ADDRESS (vm_last_addr) is a maximum address, not a size.
  */
 
-#ifdef ppc
-       _vm_object_allocate(vm_last_addr + 1,
-                           kernel_object);
-#else
        _vm_object_allocate(VM_MAX_KERNEL_ADDRESS + 1,
                            kernel_object);
 
        _vm_object_allocate(VM_MAX_KERNEL_ADDRESS + 1,
                            compressor_object);
-#endif
        kernel_object->copy_strategy = MEMORY_OBJECT_COPY_NONE;
        compressor_object->copy_strategy = MEMORY_OBJECT_COPY_NONE;
 
@@ -683,13 +797,8 @@ vm_object_bootstrap(void)
         */
 
        vm_submap_object = &vm_submap_object_store;
-#ifdef ppc
-       _vm_object_allocate(vm_last_addr + 1,
-                           vm_submap_object);
-#else
        _vm_object_allocate(VM_MAX_KERNEL_ADDRESS + 1,
                            vm_submap_object);
-#endif
        vm_submap_object->copy_strategy = MEMORY_OBJECT_COPY_NONE;
 
        /*
@@ -698,11 +807,31 @@ vm_object_bootstrap(void)
         * non-zone memory.
         */
        vm_object_reference(vm_submap_object);
+}
 
-#if    MACH_PAGEMAP
-       vm_external_module_initialize();
-#endif /* MACH_PAGEMAP */
+#if CONFIG_IOSCHED
+void
+vm_io_reprioritize_init(void)
+{
+       kern_return_t   result;
+       thread_t        thread = THREAD_NULL;
+
+       /* Initialze the I/O reprioritization subsystem */
+        lck_spin_init(&io_reprioritize_list_lock, &vm_object_lck_grp, &vm_object_lck_attr);
+        queue_init(&io_reprioritize_list);
+
+       io_reprioritize_req_zone = zinit(sizeof(struct io_reprioritize_req),
+                                        MAX_IO_REPRIORITIZE_REQS * sizeof(struct io_reprioritize_req),
+                                        4096, "io_reprioritize_req");  
+
+       result = kernel_thread_start_priority(io_reprioritize_thread, NULL, 95 /* MAXPRI_KERNEL */, &thread);
+        if (result == KERN_SUCCESS) {
+                thread_deallocate(thread);
+        } else {
+                panic("Could not create io_reprioritize_thread");
+        }
 }
+#endif
 
 void
 vm_object_reaper_init(void)
@@ -767,9 +896,10 @@ static int cache_shadows = TRUE;
 unsigned long vm_object_deallocate_shared_successes = 0;
 unsigned long vm_object_deallocate_shared_failures = 0;
 unsigned long vm_object_deallocate_shared_swap_failures = 0;
+
 __private_extern__ void
 vm_object_deallocate(
-       register vm_object_t    object)
+       vm_object_t     object)
 {
 #if VM_OBJECT_CACHE
        boolean_t       retry_cache_trim = FALSE;
@@ -798,8 +928,23 @@ vm_object_deallocate(
                return;
        }
 
-       if (object->ref_count > 2 ||
-           (!object->named && object->ref_count > 1)) {
+       if (object->ref_count == 2 &&
+           object->named) {
+               /*
+                * This "named" object's reference count is about to
+                * drop from 2 to 1:
+                * we'll need to call memory_object_last_unmap().
+                */
+       } else if (object->ref_count == 2 &&
+                  object->internal &&
+                  object->shadow != VM_OBJECT_NULL) {
+               /*
+                * This internal object's reference count is about to
+                * drop from 2 to 1 and it has a shadow object:
+                * we'll want to try and collapse this object with its
+                * shadow.
+                */
+       } else if (object->ref_count >= 2) { 
                UInt32          original_ref_count;
                volatile UInt32 *ref_count_p;
                Boolean         atomic_swap;
@@ -820,19 +965,30 @@ vm_object_deallocate(
                 * Test again as "ref_count" could have changed.
                 * "named" shouldn't change.
                 */
-               if (original_ref_count > 2 ||
-                   (!object->named && original_ref_count > 1)) {
+               if (original_ref_count == 2 &&
+                   object->named) {
+                       /* need to take slow path for m_o_last_unmap() */
+                       atomic_swap = FALSE;
+               } else if (original_ref_count == 2 &&
+                          object->internal &&
+                          object->shadow != VM_OBJECT_NULL) {
+                       /* need to take slow path for vm_object_collapse() */
+                       atomic_swap = FALSE;
+               } else if (original_ref_count < 2) { 
+                       /* need to take slow path for vm_object_terminate() */
+                       atomic_swap = FALSE;
+               } else {
+                       /* try an atomic update with the shared lock */
                        atomic_swap = OSCompareAndSwap(
                                original_ref_count,
                                original_ref_count - 1,
                                (UInt32 *) &object->ref_count);
                        if (atomic_swap == FALSE) {
                                vm_object_deallocate_shared_swap_failures++;
+                               /* fall back to the slow path... */
                        }
-
-               } else {
-                       atomic_swap = FALSE;
                }
+                       
                vm_object_unlock(object);
 
                if (atomic_swap) {
@@ -1113,13 +1269,13 @@ vm_object_page_grab(
 
        vm_object_lock_assert_exclusive(object);
 
-       next_p = (vm_page_t)queue_first(&object->memq);
+       next_p = (vm_page_t)vm_page_queue_first(&object->memq);
        p_limit = MIN(50, object->resident_page_count);
 
-       while (!queue_end(&object->memq, (queue_entry_t)next_p) && --p_limit > 0) {
+       while (!vm_page_queue_end(&object->memq, (vm_page_queue_entry_t)next_p) && --p_limit > 0) {
 
                p = next_p;
-               next_p = (vm_page_t)queue_next(&next_p->listq);
+               next_p = (vm_page_t)vm_page_queue_next(&next_p->listq);
 
                if (VM_PAGE_WIRED(p) || p->busy || p->cleaning || p->laundry || p->fictitious)
                        goto move_page_in_obj;
@@ -1134,7 +1290,7 @@ vm_object_page_grab(
 
                                if (p->reference == FALSE || p->dirty == FALSE) {
 
-                                       refmod_state = pmap_get_refmod(p->phys_page);
+                                       refmod_state = pmap_get_refmod(VM_PAGE_GET_PHYS_PAGE(p));
 
                                        if (refmod_state & VM_MEM_REFERENCED)
                                                p->reference = TRUE;
@@ -1144,7 +1300,7 @@ vm_object_page_grab(
                                }
                                if (p->dirty == FALSE && p->precious == FALSE) {
 
-                                       refmod_state = pmap_disconnect(p->phys_page);
+                                       refmod_state = pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(p));
 
                                        if (refmod_state & VM_MEM_REFERENCED)
                                                p->reference = TRUE;
@@ -1156,7 +1312,7 @@ vm_object_page_grab(
                                                goto take_page;
                                }
                        }
-                       if (p->inactive && p->reference == TRUE) {
+                       if ((p->vm_page_q_state != VM_PAGE_ON_ACTIVE_Q) && p->reference == TRUE) {
                                vm_page_activate(p);
 
                                VM_STAT_INCR(reactivations);
@@ -1164,8 +1320,8 @@ vm_object_page_grab(
                        }
                        vm_page_unlock_queues();
 move_page_in_obj:
-                       queue_remove(&object->memq, p, vm_page_t, listq);
-                       queue_enter(&object->memq, p, vm_page_t, listq);
+                       vm_page_queue_remove(&object->memq, p, vm_page_t, listq);
+                       vm_page_queue_enter(&object->memq, p, vm_page_t, listq);
 
                        p_skipped++;
                        continue;
@@ -1199,6 +1355,9 @@ static void
 vm_object_cache_remove_locked(
        vm_object_t     object)
 {
+       assert(object->purgable == VM_PURGABLE_DENY);
+       assert(object->wired_page_count == 0);
+
        queue_remove(&vm_object_cached_list, object, vm_object_t, objq);
        object->objq.next = NULL;
        object->objq.prev = NULL;
@@ -1225,6 +1384,9 @@ vm_object_cache_add(
        clock_sec_t sec;
        clock_nsec_t nsec;
 
+       assert(object->purgable == VM_PURGABLE_DENY);
+       assert(object->wired_page_count == 0);
+
        if (object->resident_page_count == 0)
                return;
        clock_get_system_nanotime(&sec, &nsec);
@@ -1297,6 +1459,9 @@ vm_object_cache_evict(
 
                        object = next_obj;
                        next_obj = (vm_object_t)queue_next(&next_obj->objq);
+
+                       assert(object->purgable == VM_PURGABLE_DENY);
+                       assert(object->wired_page_count == 0);
                        
                        if (sec < object->vo_cache_ts) {
                                KERNEL_DEBUG(0x130020c, object, object->resident_page_count, object->vo_cache_ts, sec, 0);
@@ -1316,7 +1481,7 @@ vm_object_cache_evict(
                                object = VM_OBJECT_NULL;
                                continue;
                        }
-                       if (queue_empty(&object->memq) || object->vo_cache_pages_to_scan == 0) {
+                       if (vm_page_queue_empty(&object->memq) || object->vo_cache_pages_to_scan == 0) {
                                /*
                                 * this case really shouldn't happen, but it's not fatal
                                 * so deal with it... if we don't remove the object from
@@ -1344,7 +1509,7 @@ vm_object_cache_evict(
                 * object is locked at this point and
                 * has resident pages
                 */
-               next_p = (vm_page_t)queue_first(&object->memq);
+               next_p = (vm_page_t)vm_page_queue_first(&object->memq);
 
                /*
                 * break the page scan into 2 pieces to minimize the time spent
@@ -1358,25 +1523,25 @@ vm_object_cache_evict(
                        ep_limit = EVICT_PREPARE_LIMIT;
                ep_count = 0;
 
-               while (!queue_end(&object->memq, (queue_entry_t)next_p) && object->vo_cache_pages_to_scan && ep_count < ep_limit) {
+               while (!vm_page_queue_end(&object->memq, (vm_page_queue_entry_t)next_p) && object->vo_cache_pages_to_scan && ep_count < ep_limit) {
 
                        p = next_p;
-                       next_p = (vm_page_t)queue_next(&next_p->listq);
+                       next_p = (vm_page_t)vm_page_queue_next(&next_p->listq);
 
                        object->vo_cache_pages_to_scan--;
 
                        if (VM_PAGE_WIRED(p) || p->busy || p->cleaning || p->laundry) {
-                               queue_remove(&object->memq, p, vm_page_t, listq);
-                               queue_enter(&object->memq, p, vm_page_t, listq);
+                               vm_page_queue_remove(&object->memq, p, vm_page_t, listq);
+                               vm_page_queue_enter(&object->memq, p, vm_page_t, listq);
 
                                ep_skipped++;
                                continue;
                        }
                        if (p->wpmapped || p->dirty || p->precious) {
-                               queue_remove(&object->memq, p, vm_page_t, listq);
-                               queue_enter(&object->memq, p, vm_page_t, listq);
+                               vm_page_queue_remove(&object->memq, p, vm_page_t, listq);
+                               vm_page_queue_enter(&object->memq, p, vm_page_t, listq);
 
-                               pmap_clear_reference(p->phys_page);
+                               pmap_clear_reference(VM_PAGE_GET_PHYS_PAGE(p));
                        }
                        ep_array[ep_count++] = p;
                }
@@ -1396,21 +1561,22 @@ vm_object_cache_evict(
                                 * we've already filtered out pages that are in the laundry
                                 * so if we get here, this page can't be on the pageout queue
                                 */
-                               assert(!p->pageout_queue);
-
-                               VM_PAGE_QUEUES_REMOVE(p);
-                               VM_PAGE_ENQUEUE_INACTIVE(p, TRUE);
+                               vm_page_queues_remove(p, FALSE);
+                               vm_page_enqueue_inactive(p, TRUE);
 
                                ep_moved++;
                        } else {
+#if CONFIG_PHANTOM_CACHE
+                               vm_phantom_cache_add_ghost(p);
+#endif
                                vm_page_free_prepare_queues(p);
 
-                               assert(p->pageq.next == NULL && p->pageq.prev == NULL);
+                               assert(p->pageq.next == 0 && p->pageq.prev == 0);
                                /*
                                 * Add this page to our list of reclaimed pages,
                                 * to be freed later.
                                 */
-                               p->pageq.next = (queue_entry_t) local_free_q;
+                               p->snext = local_free_q;
                                local_free_q = p;
 
                                ep_freed++;
@@ -1476,7 +1642,7 @@ vm_object_t
 vm_object_cache_trim(
        boolean_t called_from_vm_object_deallocate)
 {
-       register vm_object_t object = VM_OBJECT_NULL;
+       vm_object_t object = VM_OBJECT_NULL;
        vm_object_t shadow;
 
        for (;;) {
@@ -1582,6 +1748,8 @@ vm_object_terminate(
        XPR(XPR_VM_OBJECT, "vm_object_terminate, object 0x%X ref %d\n",
                object, object->ref_count, 0, 0, 0);
 
+       vm_object_lock_assert_exclusive(object);
+
        if (!object->pageout && (!object->temporary || object->can_persist) &&
            (object->pager != NULL || object->shadow_severed)) {
                /*
@@ -1710,6 +1878,7 @@ vm_object_terminate(
  * The VM object must be locked by caller.
  * The lock will be released on return and the VM object is no longer valid.
  */
+
 void
 vm_object_reap(
        vm_object_t object)
@@ -1722,6 +1891,18 @@ vm_object_reap(
 
        vm_object_reap_count++;
 
+       /*
+        * Disown this purgeable object to cleanup its owner's purgeable
+        * ledgers.  We need to do this before disconnecting the object
+        * from its pager, to properly account for compressed pages.
+        */
+       if (object->internal &&
+           object->purgable != VM_PURGABLE_DENY) {
+               vm_purgeable_accounting(object,
+                                       object->purgable,
+                                       TRUE); /* disown */
+       }
+
        pager = object->pager;
        object->pager = MEMORY_OBJECT_NULL;
 
@@ -1738,21 +1919,70 @@ vm_object_reap(
        /*
         * remove from purgeable queue if it's on
         */
-       if (object->internal && (object->objq.next || object->objq.prev)) {
-               purgeable_q_t queue = vm_purgeable_object_remove(object);
-               assert(queue);
+       if (object->internal) {
+               task_t owner;
+
+               owner = object->vo_purgeable_owner;
+
+               VM_OBJECT_UNWIRED(object);
+
+               if (object->purgable == VM_PURGABLE_DENY) {
+                       /* not purgeable: nothing to do */
+               } else if (object->purgable == VM_PURGABLE_VOLATILE) {
+                       purgeable_q_t queue;
+
+                       assert(object->vo_purgeable_owner == NULL);
+
+                       queue = vm_purgeable_object_remove(object);
+                       assert(queue);
+
+                       if (object->purgeable_when_ripe) {
+                               /*
+                                * Must take page lock for this -
+                                * using it to protect token queue
+                                */
+                               vm_page_lock_queues();
+                               vm_purgeable_token_delete_first(queue);
+        
+                               assert(queue->debug_count_objects>=0);
+                               vm_page_unlock_queues();
+                       }
 
-               if (object->purgeable_when_ripe) {
                        /*
-                        * Must take page lock for this -
-                        * using it to protect token queue
+                        * Update "vm_page_purgeable_count" in bulk and mark
+                        * object as VM_PURGABLE_EMPTY to avoid updating 
+                        * "vm_page_purgeable_count" again in vm_page_remove()
+                        * when reaping the pages.
                         */
-                       vm_page_lock_queues();
-                       vm_purgeable_token_delete_first(queue);
-        
-                       assert(queue->debug_count_objects>=0);
-                       vm_page_unlock_queues();
+                       unsigned int delta;
+                       assert(object->resident_page_count >=
+                              object->wired_page_count);
+                       delta = (object->resident_page_count -
+                                object->wired_page_count);
+                       if (delta != 0) {
+                               assert(vm_page_purgeable_count >= delta);
+                               OSAddAtomic(-delta,
+                                           (SInt32 *)&vm_page_purgeable_count);
+                       }
+                       if (object->wired_page_count != 0) {
+                               assert(vm_page_purgeable_wired_count >=
+                                      object->wired_page_count);
+                               OSAddAtomic(-object->wired_page_count,
+                                           (SInt32 *)&vm_page_purgeable_wired_count);
+                       }
+                       object->purgable = VM_PURGABLE_EMPTY;
+               }
+               else if (object->purgable == VM_PURGABLE_NONVOLATILE ||
+                        object->purgable == VM_PURGABLE_EMPTY) {
+                       /* remove from nonvolatile queue */
+                       assert(object->vo_purgeable_owner == TASK_NULL);
+                       vm_purgeable_nonvolatile_dequeue(object);
+               } else {
+                       panic("object %p in unexpected purgeable state 0x%x\n",
+                             object, object->purgable);
                }
+               assert(object->objq.next == NULL);
+               assert(object->objq.prev == NULL);
        }
     
        /*
@@ -1769,7 +1999,7 @@ vm_object_reap(
 
                vm_object_reap_pages(object, REAP_REAP);
        }
-       assert(queue_empty(&object->memq));
+       assert(vm_page_queue_empty(&object->memq));
        assert(object->paging_in_progress == 0);
        assert(object->activity_in_progress == 0);
        assert(object->ref_count == 0);
@@ -1791,12 +2021,15 @@ vm_object_reap(
        vm_object_paging_end(object);
        vm_object_unlock(object);
 
-#if    MACH_PAGEMAP
-       vm_external_destroy(object->existence_map, object->vo_size);
-#endif /* MACH_PAGEMAP */
-
        object->shadow = VM_OBJECT_NULL;
 
+#if VM_OBJECT_TRACKING
+       if (vm_object_tracking_inited) {
+               btlog_remove_entries_for_element(vm_object_tracking_btlog,
+                                                object);
+       }
+#endif /* VM_OBJECT_TRACKING */
+
        vm_object_lock_destroy(object);
        /*
         *      Free the space for the object.
@@ -1820,9 +2053,9 @@ unsigned int vm_max_batch = 256;
                        vm_page_t m;                                    \
                        for (m = _local_free_q;                         \
                             m != VM_PAGE_NULL;                         \
-                            m = (vm_page_t) m->pageq.next) {           \
+                            m = m->snext) {            \
                                if (m->pmapped) {                       \
-                                       pmap_disconnect(m->phys_page);  \
+                                       pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(m)); \
                                }                                       \
                        }                                               \
                }                                                       \
@@ -1862,7 +2095,7 @@ vm_object_reap_pages(
        }
                
 restart_after_sleep:
-       if (queue_empty(&object->memq))
+       if (vm_page_queue_empty(&object->memq))
                return;
        loop_count = BATCH_LIMIT(V_O_R_MAX_BATCH);
 
@@ -1871,12 +2104,12 @@ restart_after_sleep:
 
        vm_page_lockspin_queues();
 
-       next = (vm_page_t)queue_first(&object->memq);
+       next = (vm_page_t)vm_page_queue_first(&object->memq);
 
-       while (!queue_end(&object->memq, (queue_entry_t)next)) {
+       while (!vm_page_queue_end(&object->memq, (vm_page_queue_entry_t)next)) {
 
                p = next;
-               next = (vm_page_t)queue_next(&next->listq);
+               next = (vm_page_t)vm_page_queue_next(&next->listq);
 
                if (--loop_count == 0) {
                                        
@@ -1917,11 +2150,8 @@ restart_after_sleep:
 
                                goto restart_after_sleep;
                        }
-                       if (p->laundry) {
-                               p->pageout = FALSE;
-
+                       if (p->laundry)
                                vm_pageout_steal_laundry(p, TRUE);
-                       }
                }
                switch (reap_type) {
 
@@ -1945,12 +2175,10 @@ restart_after_sleep:
                                vm_page_purged_wired++;
                                continue;
                        }
-                       if (p->laundry && !p->busy && !p->cleaning) {
-                               p->pageout = FALSE;
-
+                       if (p->laundry && !p->busy && !p->cleaning)
                                vm_pageout_steal_laundry(p, TRUE);
-                       }
-                       if (p->cleaning || p->laundry) {
+
+                       if (p->cleaning || p->laundry || p->absent) {
                                /*
                                 * page is being acted upon,
                                 * so don't mess with it
@@ -1965,12 +2193,13 @@ restart_after_sleep:
                                 * sure that it gets considered by
                                 * vm_pageout_scan() later.
                                 */
-                               vm_page_deactivate(p);
+                               if (VM_PAGE_PAGEABLE(p))
+                                       vm_page_deactivate(p);
                                vm_page_purged_busy++;
                                continue;
                        }
 
-                       assert(p->object != kernel_object);
+                       assert(VM_PAGE_OBJECT(p) != kernel_object);
 
                        /*
                         * we can discard this page...
@@ -1979,7 +2208,7 @@ restart_after_sleep:
                                /*
                                 * unmap the page
                                 */
-                               pmap_disconnect_options(p->phys_page, PMAP_OPTIONS_NOFLUSH | PMAP_OPTIONS_NOREFMOD, (void *)&pmap_flush_context_storage);
+                               pmap_disconnect_options(VM_PAGE_GET_PHYS_PAGE(p), PMAP_OPTIONS_NOFLUSH | PMAP_OPTIONS_NOREFMOD, (void *)&pmap_flush_context_storage);
                        }
                        vm_page_purged_count++;
 
@@ -1997,21 +2226,25 @@ restart_after_sleep:
                                break;
                        }
                        if (p->fictitious) {
-                               assert (p->phys_page == vm_page_guard_addr);
+                               assert (VM_PAGE_GET_PHYS_PAGE(p) == vm_page_guard_addr);
                                break;
                        }
                        if (!p->dirty && p->wpmapped)
-                               p->dirty = pmap_is_modified(p->phys_page);
+                               p->dirty = pmap_is_modified(VM_PAGE_GET_PHYS_PAGE(p));
 
                        if ((p->dirty || p->precious) && !p->error && object->alive) {
 
+                               assert(!object->internal);
+                               
+                               p->free_when_done = TRUE;
+
                                if (!p->laundry) {
-                                       VM_PAGE_QUEUES_REMOVE(p);
+                                       vm_page_queues_remove(p, TRUE);
                                        /*
                                         * flush page... page will be freed
                                         * upon completion of I/O
                                         */
-                                       vm_pageout_cluster(p, TRUE);
+                                       (void)vm_pageout_cluster(p, FALSE, FALSE);
                                }
                                vm_page_unlock_queues();
                                /*
@@ -2030,12 +2263,12 @@ restart_after_sleep:
                        break;
                }
                vm_page_free_prepare_queues(p);
-               assert(p->pageq.next == NULL && p->pageq.prev == NULL);
+               assert(p->pageq.next == 0 && p->pageq.prev == 0);
                /*
                 * Add this page to our list of reclaimed pages,
                 * to be freed later.
                 */
-               p->pageq.next = (queue_entry_t) local_free_q;
+               p->snext = local_free_q;
                local_free_q = p;
        }
        vm_page_unlock_queues();
@@ -2288,9 +2521,9 @@ uint32_t vm_object_deactivate_all_pages_pages = 0;
  */
 static void
 vm_object_deactivate_all_pages(
-       register vm_object_t    object)
+       vm_object_t     object)
 {
-       register vm_page_t      p;
+       vm_page_t               p;
        int                     loop_count;
 #if VM_OBJ_DEACT_ALL_STATS
        int                     pages_count;
@@ -2302,7 +2535,7 @@ vm_object_deactivate_all_pages(
        pages_count = 0;
 #endif /* VM_OBJ_DEACT_ALL_STATS */
        vm_page_lock_queues();
-       queue_iterate(&object->memq, p, vm_page_t, listq) {
+       vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
                if (--loop_count == 0) {
 #if VM_OBJ_DEACT_ALL_STATS
                        hw_atomic_add(&vm_object_deactivate_all_pages_batches,
@@ -2314,7 +2547,7 @@ vm_object_deactivate_all_pages(
                        lck_mtx_yield(&vm_page_queue_lock);
                        loop_count = BATCH_LIMIT(V_O_D_A_P_MAX_BATCH);
                }
-               if (!p->busy && !p->throttled) {
+               if (!p->busy && (p->vm_page_q_state != VM_PAGE_ON_THROTTLED_Q)) {
 #if VM_OBJ_DEACT_ALL_STATS
                        pages_count++;
 #endif /* VM_OBJ_DEACT_ALL_STATS */
@@ -2417,68 +2650,16 @@ page_is_paged_out(
        vm_object_t             object,
        vm_object_offset_t      offset)
 {
-       kern_return_t   kr;
-       memory_object_t pager;
-
-       /*
-        * Check the existence map for the page if we have one, otherwise
-        * ask the pager about this page.
-        */
-
-#if MACH_PAGEMAP
-       if (object->existence_map) {
-               if (vm_external_state_get(object->existence_map, offset)
-                   == VM_EXTERNAL_STATE_EXISTS) {
-                       /*
-                        * We found the page
-                        */
-
-                       return TRUE;
-               }
-       } else
-#endif /* MACH_PAGEMAP */
        if (object->internal &&
           object->alive &&
           !object->terminating &&
           object->pager_ready) {
 
-               if (COMPRESSED_PAGER_IS_ACTIVE || DEFAULT_FREEZER_COMPRESSED_PAGER_IS_ACTIVE) {
-                       if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset) 
-                           == VM_EXTERNAL_STATE_EXISTS) {
-                               return TRUE;
-                       } else {
-                               return FALSE;
-                       }
-               }
-
-               /*
-                * We're already holding a "paging in progress" reference
-                * so the object can't disappear when we release the lock.
-                */
-
-               assert(object->paging_in_progress);
-               pager = object->pager;
-               vm_object_unlock(object);
-
-               kr = memory_object_data_request(
-                       pager,
-                       offset + object->paging_offset,
-                       0,      /* just poke the pager */
-                       VM_PROT_READ,
-                       NULL);
-
-               vm_object_lock(object);
-
-               if (kr == KERN_SUCCESS) {
-
-                       /*
-                        * We found the page
-                        */
-
+               if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset) 
+                   == VM_EXTERNAL_STATE_EXISTS) {
                        return TRUE;
                }
        }
-
        return FALSE;
 }
 
@@ -2513,7 +2694,9 @@ deactivate_pages_in_object(
        boolean_t               reusable_page,
        boolean_t               all_reusable,
        chunk_state_t           *chunk_state,
-       pmap_flush_context      *pfc)
+       pmap_flush_context      *pfc,
+       struct pmap             *pmap,
+       vm_map_offset_t         pmap_offset)
 {
        vm_page_t       m;
        int             p;
@@ -2534,7 +2717,7 @@ deactivate_pages_in_object(
        dw_count = 0;
        dw_limit = DELAYED_WORK_LIMIT(DEFAULT_DELAYED_WORK_LIMIT);
 
-       for(p = 0; size && CHUNK_NOT_COMPLETE(*chunk_state); p++, size -= PAGE_SIZE_64, offset += PAGE_SIZE_64) {
+       for(p = 0; size && CHUNK_NOT_COMPLETE(*chunk_state); p++, size -= PAGE_SIZE_64, offset += PAGE_SIZE_64, pmap_offset += PAGE_SIZE_64) {
 
                /*
                 * If this offset has already been found and handled in a higher level object, then don't
@@ -2561,9 +2744,11 @@ deactivate_pages_in_object(
        
                        if (( !VM_PAGE_WIRED(m)) && (!m->private) && (!m->gobbled) && (!m->busy) && (!m->laundry)) {
                                int     clear_refmod;
+                               int     pmap_options;
        
                                dwp->dw_mask = 0;
 
+                               pmap_options = 0;
                                clear_refmod = VM_MEM_REFERENCED;
                                dwp->dw_mask |= DW_clear_reference;
 
@@ -2574,13 +2759,13 @@ deactivate_pages_in_object(
                                                 * to simulate it being
                                                 * reclaimed and re-faulted.
                                                 */
-                                               pmap_zero_page(m->phys_page);
+                                               pmap_zero_page(VM_PAGE_GET_PHYS_PAGE(m));
                                        }
                                        m->precious = FALSE;
                                        m->dirty = FALSE;
 
                                        clear_refmod |= VM_MEM_MODIFIED;
-                                       if (m->throttled) {
+                                       if (m->vm_page_q_state == VM_PAGE_ON_THROTTLED_Q) {
                                                /*
                                                 * This page is now clean and
                                                 * reclaimable.  Move it out
@@ -2590,11 +2775,8 @@ deactivate_pages_in_object(
                                                 */
                                                dwp->dw_mask |= DW_move_page;
                                        }
-#if    MACH_PAGEMAP
-                                       vm_external_state_clr(object->existence_map, offset);
-#endif /* MACH_PAGEMAP */
-                                       VM_COMPRESSOR_PAGER_STATE_CLR(object,
-                                                                     offset);
+
+                                       VM_COMPRESSOR_PAGER_STATE_CLR(object, offset);
 
                                        if (reusable_page && !m->reusable) {
                                                assert(!all_reusable);
@@ -2603,11 +2785,21 @@ deactivate_pages_in_object(
                                                object->reusable_page_count++;
                                                assert(object->resident_page_count >= object->reusable_page_count);
                                                reusable++;
+                                               /*
+                                                * Tell pmap this page is now
+                                                * "reusable" (to update pmap
+                                                * stats for all mappings).
+                                                */
+                                               pmap_options |= PMAP_OPTIONS_SET_REUSABLE;
                                        }
                                }
-                               pmap_clear_refmod_options(m->phys_page, clear_refmod, PMAP_OPTIONS_NOFLUSH, (void *)pfc);
+                               pmap_options |= PMAP_OPTIONS_NOFLUSH;
+                               pmap_clear_refmod_options(VM_PAGE_GET_PHYS_PAGE(m),
+                                                         clear_refmod,
+                                                         pmap_options,
+                                                         (void *)pfc);
 
-                               if (!m->throttled && !(reusable_page || all_reusable))
+                               if ((m->vm_page_q_state != VM_PAGE_ON_THROTTLED_Q) && !(reusable_page || all_reusable))
                                        dwp->dw_mask |= DW_move_page;
                                
                                if (dwp->dw_mask)
@@ -2621,7 +2813,7 @@ deactivate_pages_in_object(
                                                vm_page_stats_reusable.reusable += reusable;
                                                reusable = 0;
                                        }
-                                       vm_page_do_delayed_work(object, &dw_array[0], dw_count);
+                                       vm_page_do_delayed_work(object, VM_KERN_MEMORY_NONE, &dw_array[0], dw_count);
 
                                        dwp = &dw_array[0];
                                        dw_count = 0;
@@ -2645,11 +2837,24 @@ deactivate_pages_in_object(
                                 */
 
                                if ((kill_page) && (object->internal)) {
-#if    MACH_PAGEMAP
-                                       vm_external_state_clr(object->existence_map, offset);
-#endif /* MACH_PAGEMAP */
-                                       VM_COMPRESSOR_PAGER_STATE_CLR(object,
-                                                                     offset);
+
+                                       VM_COMPRESSOR_PAGER_STATE_CLR(object, offset);
+
+                                       if (pmap != PMAP_NULL) {
+                                               /*
+                                                * Tell pmap that this page
+                                                * is no longer mapped, to
+                                                * adjust the footprint ledger
+                                                * because this page is no
+                                                * longer compressed.
+                                                */
+                                               pmap_remove_options(
+                                                       pmap,
+                                                       pmap_offset,
+                                                       (pmap_offset +
+                                                        PAGE_SIZE),
+                                                       PMAP_OPTIONS_REMOVE);
+                                       }
                                }
                        }
                }
@@ -2662,7 +2867,7 @@ deactivate_pages_in_object(
        }
                
        if (dw_count)
-               vm_page_do_delayed_work(object, &dw_array[0], dw_count);
+               vm_page_do_delayed_work(object, VM_KERN_MEMORY_NONE, &dw_array[0], dw_count);
 }
 
 
@@ -2683,7 +2888,9 @@ deactivate_a_chunk(
        boolean_t               kill_page,
        boolean_t               reusable_page,
        boolean_t               all_reusable,
-       pmap_flush_context      *pfc)
+       pmap_flush_context      *pfc,
+       struct pmap             *pmap,
+       vm_map_offset_t         pmap_offset)
 {
        vm_object_t             object;
        vm_object_t             tmp_object;
@@ -2716,7 +2923,7 @@ deactivate_a_chunk(
        while (object && CHUNK_NOT_COMPLETE(chunk_state)) {
                vm_object_paging_begin(object);
 
-               deactivate_pages_in_object(object, offset, length, kill_page, reusable_page, all_reusable, &chunk_state, pfc);
+               deactivate_pages_in_object(object, offset, length, kill_page, reusable_page, all_reusable, &chunk_state, pfc, pmap, pmap_offset);
 
                vm_object_paging_end(object);
 
@@ -2762,7 +2969,9 @@ vm_object_deactivate_pages(
        vm_object_offset_t      offset,
        vm_object_size_t        size,
        boolean_t               kill_page,
-       boolean_t               reusable_page)
+       boolean_t               reusable_page,
+       struct pmap             *pmap,
+       vm_map_offset_t         pmap_offset)
 {
        vm_object_size_t        length;
        boolean_t               all_reusable;
@@ -2777,6 +2986,13 @@ vm_object_deactivate_pages(
 
 
        all_reusable = FALSE;
+#if 11
+       /*
+        * For the sake of accurate "reusable" pmap stats, we need 
+        * to tell pmap about each page that is no longer "reusable",
+        * so we can't do the "all_reusable" optimization.
+        */
+#else
        if (reusable_page &&
            object->internal &&
            object->vo_size != 0 &&
@@ -2785,6 +3001,7 @@ vm_object_deactivate_pages(
                all_reusable = TRUE;
                reusable_page = FALSE;
        }
+#endif
 
        if ((reusable_page || all_reusable) && object->all_reusable) {
                /* This means MADV_FREE_REUSABLE has been called twice, which 
@@ -2795,10 +3012,11 @@ vm_object_deactivate_pages(
        pmap_flush_context_init(&pmap_flush_context_storage);
 
        while (size) {
-               length = deactivate_a_chunk(object, offset, size, kill_page, reusable_page, all_reusable, &pmap_flush_context_storage);
+               length = deactivate_a_chunk(object, offset, size, kill_page, reusable_page, all_reusable, &pmap_flush_context_storage, pmap, pmap_offset);
 
                size -= length;
                offset += length;
+               pmap_offset += length;
        }
        pmap_flush(&pmap_flush_context_storage);
 
@@ -2841,6 +3059,17 @@ vm_object_reuse_pages(
                        (object)->reusable_page_count--;                \
                        (m)->reusable = FALSE;                          \
                        (reused)++;                                     \
+                       /*                                              \
+                        * Tell pmap that this page is no longer        \
+                        * "reusable", to update the "reusable" stats   \
+                        * for all the pmaps that have mapped this      \
+                        * page.                                        \
+                        */                                             \
+                       pmap_clear_refmod_options(VM_PAGE_GET_PHYS_PAGE((m)), \
+                                                 0, /* refmod */       \
+                                                 (PMAP_OPTIONS_CLEAR_REUSABLE \
+                                                  | PMAP_OPTIONS_NOFLUSH), \
+                                                 NULL);                \
                }                                                       \
        MACRO_END
 
@@ -2850,6 +3079,8 @@ vm_object_reuse_pages(
        vm_object_lock_assert_exclusive(object);
 
        if (object->all_reusable) {
+               panic("object %p all_reusable: can't update pmap stats\n",
+                     object);
                assert(object->reusable_page_count == 0);
                object->all_reusable = FALSE;
                if (end_offset - start_offset == object->vo_size ||
@@ -2858,7 +3089,7 @@ vm_object_reuse_pages(
                        reused = object->resident_page_count;
                } else {
                        vm_page_stats_reusable.partial_reuse_calls++;
-                       queue_iterate(&object->memq, m, vm_page_t, listq) {
+                       vm_page_queue_iterate(&object->memq, m, vm_page_t, listq) {
                                if (m->offset < start_offset ||
                                    m->offset >= end_offset) {
                                        m->reusable = TRUE;
@@ -2885,7 +3116,7 @@ vm_object_reuse_pages(
                }
        } else {
                vm_page_stats_reusable.partial_reuse_calls++;
-               queue_iterate(&object->memq, m, vm_page_t, listq) {
+               vm_page_queue_iterate(&object->memq, m, vm_page_t, listq) {
                        if (object->reusable_page_count == 0) {
                                break;
                        }
@@ -2929,8 +3160,8 @@ vm_object_reuse_pages(
 
 __private_extern__ void
 vm_object_pmap_protect(
-       register vm_object_t            object,
-       register vm_object_offset_t     offset,
+       vm_object_t                     object,
+       vm_object_offset_t              offset,
        vm_object_size_t                size,
        pmap_t                          pmap,
        vm_map_offset_t                 pmap_start,
@@ -2942,8 +3173,8 @@ vm_object_pmap_protect(
 
 __private_extern__ void
 vm_object_pmap_protect_options(
-       register vm_object_t            object,
-       register vm_object_offset_t     offset,
+       vm_object_t                     object,
+       vm_object_offset_t              offset,
        vm_object_size_t                size,
        pmap_t                          pmap,
        vm_map_offset_t                 pmap_start,
@@ -3021,7 +3252,7 @@ vm_object_pmap_protect_options(
 
                end = offset + size;
 
-               queue_iterate(&object->memq, p, vm_page_t, listq) {
+               vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
                        if (!p->fictitious && (offset <= p->offset) && (p->offset < end)) {
                                vm_map_offset_t start;
 
@@ -3037,7 +3268,7 @@ vm_object_pmap_protect_options(
                                                &pmap_flush_context_storage);
                                else
                                        pmap_page_protect_options(
-                                               p->phys_page,
+                                               VM_PAGE_GET_PHYS_PAGE(p),
                                                prot,
                                                options | PMAP_OPTIONS_NOFLUSH,
                                                &pmap_flush_context_storage);
@@ -3072,7 +3303,7 @@ vm_object_pmap_protect_options(
                                                &pmap_flush_context_storage);
                                else
                                        pmap_page_protect_options(
-                                               p->phys_page,
+                                               VM_PAGE_GET_PHYS_PAGE(p),
                                                prot,
                                                options | PMAP_OPTIONS_NOFLUSH,
                                                &pmap_flush_context_storage);
@@ -3088,7 +3319,7 @@ vm_object_pmap_protect_options(
                 * Must follow shadow chain to remove access
                 * to pages in shadowed objects.
                 */
-               register vm_object_t    next_object;
+               vm_object_t     next_object;
 
                next_object = object->shadow;
                if (next_object != VM_OBJECT_NULL) {
@@ -3148,7 +3379,7 @@ vm_object_pmap_protect_options(
  */
 __private_extern__ kern_return_t
 vm_object_copy_slowly(
-       register vm_object_t    src_object,
+       vm_object_t             src_object,
        vm_object_offset_t      src_offset,
        vm_object_size_t        size,
        boolean_t               interruptible,
@@ -3191,7 +3422,8 @@ vm_object_copy_slowly(
 
        fault_info.interruptible = interruptible;
        fault_info.behavior  = VM_BEHAVIOR_SEQUENTIAL;
-       fault_info.user_tag  = 0;
+       fault_info.user_tag = 0;
+       fault_info.pmap_options = 0;
        fault_info.lo_offset = src_offset;
        fault_info.hi_offset = src_offset + size;
        fault_info.no_cache  = FALSE;
@@ -3230,11 +3462,40 @@ vm_object_copy_slowly(
                        vm_prot_t       prot = VM_PROT_READ;
                        vm_page_t       _result_page;
                        vm_page_t       top_page;
-                       register
                        vm_page_t       result_page;
                        kern_return_t   error_code;
+                       vm_object_t     result_page_object;
+
 
                        vm_object_lock(src_object);
+
+                       if (src_object->internal &&
+                           src_object->shadow == VM_OBJECT_NULL &&
+                           (vm_page_lookup(src_object,
+                                           src_offset) == VM_PAGE_NULL) &&
+                           (src_object->pager == NULL ||
+                            (VM_COMPRESSOR_PAGER_STATE_GET(src_object,
+                                                           src_offset) ==
+                             VM_EXTERNAL_STATE_ABSENT))) {
+                               /*
+                                * This page is neither resident nor compressed
+                                * and there's no shadow object below 
+                                * "src_object", so this page is really missing.
+                                * There's no need to zero-fill it just to copy
+                                * it:  let's leave it missing in "new_object"
+                                * and get zero-filled on demand.
+                                */
+                               vm_object_unlock(src_object);
+                               /* free the unused "new_page"... */
+                               vm_object_lock(new_object);
+                               VM_PAGE_FREE(new_page);
+                               new_page = VM_PAGE_NULL;
+                               vm_object_unlock(new_object);
+                               /* ...and go to next page in "src_object" */
+                               result = VM_FAULT_SUCCESS;
+                               break;
+                       }
+
                        vm_object_paging_begin(src_object);
 
                        if (size > (vm_size_t) -1) {
@@ -3257,6 +3518,7 @@ vm_object_copy_slowly(
                        switch(result) {
                        case VM_FAULT_SUCCESS:
                                result_page = _result_page;
+                               result_page_object = VM_PAGE_OBJECT(result_page);
 
                                /*
                                 *      Copy the page to the new object.
@@ -3268,7 +3530,7 @@ vm_object_copy_slowly(
                                 */
 
                                vm_page_copy(result_page, new_page);
-                               vm_object_unlock(result_page->object);
+                               vm_object_unlock(result_page_object);
 
                                /*
                                 *      Let go of both pages (make them
@@ -3279,14 +3541,14 @@ vm_object_copy_slowly(
                                PAGE_WAKEUP_DONE(new_page);
                                vm_object_unlock(new_object);
 
-                               vm_object_lock(result_page->object);
+                               vm_object_lock(result_page_object);
                                PAGE_WAKEUP_DONE(result_page);
 
                                vm_page_lockspin_queues();
-                               if (!result_page->active &&
-                                   !result_page->inactive &&
-                                   !result_page->throttled)
+                               if ((result_page->vm_page_q_state == VM_PAGE_ON_SPECULATIVE_Q) ||
+                                   (result_page->vm_page_q_state == VM_PAGE_NOT_ON_Q)) {
                                        vm_page_activate(result_page);
+                               }
                                vm_page_activate(new_page);
                                vm_page_unlock_queues();
 
@@ -3295,7 +3557,7 @@ vm_object_copy_slowly(
                                 *      top-level placeholder page, if any.
                                 */
 
-                               vm_fault_cleanup(result_page->object,
+                               vm_fault_cleanup(result_page_object,
                                                 top_page);
 
                                break;
@@ -3631,6 +3893,7 @@ vm_object_copy_delayed(
         *      the original object must be done carefully, to avoid deadlock.
         */
 
+       copy_size = vm_object_round_page(copy_size);
  Retry:
  
        /*
@@ -3722,7 +3985,7 @@ vm_object_copy_delayed(
                                pmap_flush_context_init(&pmap_flush_context_storage);
                                delayed_pmap_flush = FALSE;
 
-                               queue_iterate(&src_object->memq, p, vm_page_t, listq) {
+                               vm_page_queue_iterate(&src_object->memq, p, vm_page_t, listq) {
                                        if (!p->fictitious && 
                                            p->offset >= old_copy->vo_size && 
                                            p->offset < copy_size) {
@@ -3739,7 +4002,7 @@ vm_object_copy_delayed(
 
                                                        return VM_OBJECT_NULL;
                                                } else {
-                                                       pmap_page_protect_options(p->phys_page, (VM_PROT_ALL & ~VM_PROT_WRITE),
+                                                       pmap_page_protect_options(VM_PAGE_GET_PHYS_PAGE(p), (VM_PROT_ALL & ~VM_PROT_WRITE),
                                                                                  PMAP_OPTIONS_NOFLUSH, (void *)&pmap_flush_context_storage);
                                                        delayed_pmap_flush = TRUE;
                                                }
@@ -3822,7 +4085,7 @@ vm_object_copy_delayed(
        pmap_flush_context_init(&pmap_flush_context_storage);
        delayed_pmap_flush = FALSE;
 
-       queue_iterate(&src_object->memq, p, vm_page_t, listq) {
+       vm_page_queue_iterate(&src_object->memq, p, vm_page_t, listq) {
                if (!p->fictitious && p->offset < copy_size) {
                        if (VM_PAGE_WIRED(p)) {
                                if (old_copy)
@@ -3836,7 +4099,7 @@ vm_object_copy_delayed(
 
                                return VM_OBJECT_NULL;
                        } else {
-                               pmap_page_protect_options(p->phys_page, (VM_PROT_ALL & ~VM_PROT_WRITE),
+                               pmap_page_protect_options(VM_PAGE_GET_PHYS_PAGE(p), (VM_PROT_ALL & ~VM_PROT_WRITE),
                                                          PMAP_OPTIONS_NOFLUSH, (void *)&pmap_flush_context_storage);
                                delayed_pmap_flush = TRUE;
                        }
@@ -3903,7 +4166,7 @@ vm_object_copy_delayed(
  */
 __private_extern__ kern_return_t
 vm_object_copy_strategically(
-       register vm_object_t    src_object,
+       vm_object_t             src_object,
        vm_object_offset_t      src_offset,
        vm_object_size_t        size,
        vm_object_t             *dst_object,    /* OUT */
@@ -4017,8 +4280,8 @@ vm_object_shadow(
        vm_object_offset_t      *offset,        /* IN/OUT */
        vm_object_size_t        length)
 {
-       register vm_object_t    source;
-       register vm_object_t    result;
+       vm_object_t     source;
+       vm_object_t     result;
 
        source = *object;
        assert(source != VM_OBJECT_NULL);
@@ -4052,14 +4315,28 @@ vm_object_shadow(
         *      (freeing up the extra data it might contain and that
         *      we don't need).
         */
+
+       assert(source->copy_strategy != MEMORY_OBJECT_COPY_NONE); /* Purgeable objects shouldn't have shadow objects. */
+
        if (vm_object_shadow_check &&
            source->vo_size == length &&
            source->ref_count == 1 &&
            (source->shadow == VM_OBJECT_NULL ||
             source->shadow->copy == VM_OBJECT_NULL) )
        {
-               source->shadowed = FALSE;
-               return FALSE;
+               /* lock the object and check again */
+               vm_object_lock(source);
+               if (source->vo_size == length &&
+                   source->ref_count == 1 &&
+                   (source->shadow == VM_OBJECT_NULL ||
+                    source->shadow->copy == VM_OBJECT_NULL))
+               {
+                       source->shadowed = FALSE;
+                       vm_object_unlock(source);
+                       return FALSE;
+               }
+               /* things changed while we were locking "source"... */
+               vm_object_unlock(source);
        }
 
        /*
@@ -4099,7 +4376,7 @@ vm_object_shadow(
  *     the memory_object requires careful synchronization.
  *
  *     All associations are created by memory_object_create_named
- *  for external pagers and vm_object_pager_create for internal
+ *  for external pagers and vm_object_compressor_pager_create for internal
  *  objects as follows:
  *
  *             pager:  the memory_object itself, supplied by
@@ -4189,7 +4466,7 @@ vm_object_enter(
        boolean_t               init,
        boolean_t               named)
 {
-       register vm_object_t    object;
+       vm_object_t             object;
        vm_object_t             new_object;
        boolean_t               must_init;
        vm_object_hash_entry_t  entry, new_entry;
@@ -4221,12 +4498,31 @@ Retry:
                                assert(new_entry == VM_OBJECT_HASH_ENTRY_NULL);
                                new_entry = vm_object_hash_entry_alloc(pager);
                                new_object = vm_object_allocate(size);
+                               /*
+                                * Set new_object->hashed now, while noone
+                                * knows about this object yet and we
+                                * don't need to lock it.  Once it's in
+                                * the hash table, we would have to lock
+                                * the object to set its "hashed" bit and
+                                * we can't lock the object while holding
+                                * the hash lock as a spinlock...
+                                */
+                               new_object->hashed = TRUE;
                                lck = vm_object_hash_lock_spin(pager);
                        } else {
                                /*
                                 *      Lookup failed twice, and we have something
                                 *      to insert; set the object.
                                 */
+                               /*
+                                * We can't lock the object here since we're
+                                * holding the hash lock as a spin lock.
+                                * We've already pre-set "new_object->hashed"
+                                * when we created "new_object" above, so we
+                                * won't need to modify the object in
+                                * vm_object_hash_insert().
+                                */
+                               assert(new_object->hashed);
                                vm_object_hash_insert(new_entry, new_object);
                                entry = new_entry;
                                new_entry = VM_OBJECT_HASH_ENTRY_NULL;
@@ -4313,8 +4609,16 @@ Retry:
         *      throw away ours.
         */
 
-       if (new_object != VM_OBJECT_NULL)
+       if (new_object != VM_OBJECT_NULL) {
+               /*
+                * Undo the pre-setting of "new_object->hashed" before
+                * deallocating "new_object", since we did not insert it
+                * into the hash table after all.
+                */
+               assert(new_object->hashed);
+               new_object->hashed = FALSE;
                vm_object_deallocate(new_object);
+       }
 
        if (new_entry != VM_OBJECT_HASH_ENTRY_NULL)
                vm_object_hash_entry_free(new_entry);
@@ -4362,6 +4666,7 @@ Retry:
                if (named)
                        object->named = TRUE;
                if (internal) {
+                       vm_object_lock_assert_exclusive(object);
                        object->pager_ready = TRUE;
                        vm_object_wakeup(object, VM_OBJECT_EVENT_PAGER_READY);
                }
@@ -4395,7 +4700,7 @@ Retry:
 }
 
 /*
- *     Routine:        vm_object_pager_create
+ *     Routine:        vm_object_compressor_pager_create
  *     Purpose:
  *             Create a memory object for an internal object.
  *     In/out conditions:
@@ -4403,31 +4708,22 @@ Retry:
  *             it may be unlocked within this call.
  *     Limitations:
  *             Only one thread may be performing a
- *             vm_object_pager_create on an object at
+ *             vm_object_compressor_pager_create on an object at
  *             a time.  Presumably, only the pageout
  *             daemon will be using this routine.
  */
 
 void
-vm_object_pager_create(
-       register vm_object_t    object)
+vm_object_compressor_pager_create(
+       vm_object_t     object)
 {
        memory_object_t         pager;
        vm_object_hash_entry_t  entry;
        lck_mtx_t               *lck;
-#if    MACH_PAGEMAP
-       vm_object_size_t        size;
-       vm_external_map_t       map;
-#endif /* MACH_PAGEMAP */
-
-       XPR(XPR_VM_OBJECT, "vm_object_pager_create, object 0x%X\n",
-               object, 0,0,0,0);
+       vm_object_t             pager_object = VM_OBJECT_NULL;
 
        assert(object != kernel_object);
 
-       if (memory_manager_default_check() != KERN_SUCCESS)
-               return;
-
        /*
         *      Prevent collapse or termination by holding a paging reference
         */
@@ -4455,24 +4751,15 @@ vm_object_pager_create(
        object->pager_created = TRUE;
        object->paging_offset = 0;
                
-#if    MACH_PAGEMAP
-       size = object->vo_size;
-#endif /* MACH_PAGEMAP */
        vm_object_unlock(object);
 
-#if    MACH_PAGEMAP
-       if (DEFAULT_PAGER_IS_ACTIVE) {
-               map = vm_external_create(size);
-               vm_object_lock(object);
-               assert(object->vo_size == size);
-               object->existence_map = map;
-               vm_object_unlock(object);
-       }
-#endif /* MACH_PAGEMAP */
-
-       if ((uint32_t) object->vo_size != object->vo_size) {
-               panic("vm_object_pager_create(): object size 0x%llx >= 4GB\n",
-                     (uint64_t) object->vo_size);
+       if ((uint32_t) (object->vo_size/PAGE_SIZE) !=
+           (object->vo_size/PAGE_SIZE)) {
+               panic("vm_object_compressor_pager_create(%p): "
+                     "object size 0x%llx >= 0x%llx\n",
+                     object,
+                     (uint64_t) object->vo_size,
+                     0x0FFFFFFFFULL*PAGE_SIZE);
        }
 
        /*
@@ -4483,26 +4770,28 @@ vm_object_pager_create(
         *      user will ever map this object.
         */
        {
-               memory_object_default_t         dmm;
-
-               /* acquire a reference for the default memory manager */
-               dmm = memory_manager_default_reference();
-
                assert(object->temporary);
 
                /* create our new memory object */
-               assert((vm_size_t) object->vo_size == object->vo_size);
-               (void) memory_object_create(dmm, (vm_size_t) object->vo_size,
-                                           &pager);
-
-               memory_object_default_deallocate(dmm);
+               assert((uint32_t) (object->vo_size/PAGE_SIZE) ==
+                      (object->vo_size/PAGE_SIZE));
+               (void) compressor_memory_object_create(
+                       (memory_object_size_t) object->vo_size,
+                       &pager);
+               if (pager == NULL) {
+                       panic("vm_object_compressor_pager_create(): "
+                             "no pager for object %p size 0x%llx\n",
+                             object, (uint64_t) object->vo_size);
+               }
        }
 
        entry = vm_object_hash_entry_alloc(pager);
 
+       vm_object_lock(object);
        lck = vm_object_hash_lock_spin(pager);
        vm_object_hash_insert(entry, object);
        vm_object_hash_unlock(lck);
+       vm_object_unlock(object);
 
        /*
         *      A reference was returned by
@@ -4510,107 +4799,11 @@ vm_object_pager_create(
         *      copied by vm_object_enter().
         */
 
-       if (vm_object_enter(pager, object->vo_size, TRUE, TRUE, FALSE) != object)
-               panic("vm_object_pager_create: mismatch");
-
-       /*
-        *      Drop the reference we were passed.
-        */
-       memory_object_deallocate(pager);
-
-       vm_object_lock(object);
-
-       /*
-        *      Release the paging reference
-        */
-       vm_object_paging_end(object);
-}
-
-void
-vm_object_compressor_pager_create(
-       register vm_object_t    object)
-{
-       memory_object_t         pager;
-       vm_object_hash_entry_t  entry;
-       lck_mtx_t               *lck;
-
-       assert(object != kernel_object);
-
-       /*
-        *      Prevent collapse or termination by holding a paging reference
-        */
-
-       vm_object_paging_begin(object);
-       if (object->pager_created) {
-               /*
-                *      Someone else got to it first...
-                *      wait for them to finish initializing the ports
-                */
-               while (!object->pager_initialized) {
-                       vm_object_sleep(object,
-                                       VM_OBJECT_EVENT_INITIALIZED,
-                                       THREAD_UNINT);
-               }
-               vm_object_paging_end(object);
-               return;
-       }
-
-       /*
-        *      Indicate that a memory object has been assigned
-        *      before dropping the lock, to prevent a race.
-        */
-
-       object->pager_created = TRUE;
-       object->paging_offset = 0;
-               
-       vm_object_unlock(object);
-
-       if ((uint32_t) (object->vo_size/PAGE_SIZE) !=
-           (object->vo_size/PAGE_SIZE)) {
-               panic("vm_object_compressor_pager_create(%p): "
-                     "object size 0x%llx >= 0x%llx\n",
-                     object,
-                     (uint64_t) object->vo_size,
-                     0x0FFFFFFFFULL*PAGE_SIZE);
-       }
-
-       /*
-        *      Create the [internal] pager, and associate it with this object.
-        *
-        *      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.
-        */
-       {
-               assert(object->temporary);
-
-               /* create our new memory object */
-               assert((uint32_t) (object->vo_size/PAGE_SIZE) ==
-                      (object->vo_size/PAGE_SIZE));
-               (void) compressor_memory_object_create(
-                       (memory_object_size_t) object->vo_size,
-                       &pager);
-               if (pager == NULL) {
-                       panic("vm_object_compressor_pager_create(): "
-                             "no pager for object %p size 0x%llx\n",
-                             object, (uint64_t) object->vo_size);
-               }
-       }
-
-       entry = vm_object_hash_entry_alloc(pager);
-
-       lck = vm_object_hash_lock_spin(pager);
-       vm_object_hash_insert(entry, object);
-       vm_object_hash_unlock(lck);
-
-       /*
-        *      A reference was returned by
-        *      memory_object_create(), and it is
-        *      copied by vm_object_enter().
-        */
-
-       if (vm_object_enter(pager, object->vo_size, TRUE, TRUE, FALSE) != object)
-               panic("vm_object_compressor_pager_create: mismatch");
+       pager_object = vm_object_enter(pager, object->vo_size, TRUE, TRUE, FALSE);
+
+       if (pager_object != object) {
+               panic("vm_object_compressor_pager_create: mismatch (pager: %p, pager_object: %p, orig_object: %p, orig_object size: 0x%llx)\n", pager, pager_object, object, (uint64_t) object->vo_size);
+       }
 
        /*
         *      Drop the reference we were passed.
@@ -4661,13 +4854,85 @@ static long     object_bypasses  = 0;
 static boolean_t       vm_object_collapse_allowed = TRUE;
 static boolean_t       vm_object_bypass_allowed = TRUE;
 
-#if MACH_PAGEMAP
-static int     vm_external_discarded;
-static int     vm_external_collapsed;
-#endif
-
 unsigned long vm_object_collapse_encrypted = 0;
 
+void vm_object_do_collapse_compressor(vm_object_t object,
+                                     vm_object_t backing_object);
+void
+vm_object_do_collapse_compressor(
+       vm_object_t object,
+       vm_object_t backing_object)
+{
+       vm_object_offset_t new_offset, backing_offset;
+       vm_object_size_t size;
+
+       vm_counters.do_collapse_compressor++;
+
+       vm_object_lock_assert_exclusive(object);
+       vm_object_lock_assert_exclusive(backing_object);
+
+       size = object->vo_size;
+
+       /*
+        *      Move all compressed pages from backing_object
+        *      to the parent.
+        */
+
+       for (backing_offset = object->vo_shadow_offset;
+            backing_offset < object->vo_shadow_offset + object->vo_size;
+            backing_offset += PAGE_SIZE) {
+               memory_object_offset_t backing_pager_offset;
+
+               /* find the next compressed page at or after this offset */
+               backing_pager_offset = (backing_offset +
+                                       backing_object->paging_offset);
+               backing_pager_offset = vm_compressor_pager_next_compressed(
+                       backing_object->pager,
+                       backing_pager_offset);
+               if (backing_pager_offset == (memory_object_offset_t) -1) {
+                       /* no more compressed pages */
+                       break;
+               }
+               backing_offset = (backing_pager_offset -
+                                 backing_object->paging_offset);
+
+               new_offset = backing_offset - object->vo_shadow_offset;
+
+               if (new_offset >= object->vo_size) {
+                       /* we're out of the scope of "object": done */
+                       break;
+               }
+
+               if ((vm_page_lookup(object, new_offset) != VM_PAGE_NULL) ||
+                   (vm_compressor_pager_state_get(object->pager,
+                                                  (new_offset +
+                                                   object->paging_offset)) ==
+                    VM_EXTERNAL_STATE_EXISTS)) {
+                       /*
+                        * This page already exists in object, resident or
+                        * compressed.
+                        * We don't need this compressed page in backing_object
+                        * and it will be reclaimed when we release
+                        * backing_object.
+                        */
+                       continue;
+               }
+
+               /*
+                * backing_object has this page in the VM compressor and
+                * we need to transfer it to object.
+                */
+               vm_counters.do_collapse_compressor_pages++;
+               vm_compressor_pager_transfer(
+                       /* destination: */
+                       object->pager,
+                       (new_offset + object->paging_offset),
+                       /* source: */
+                       backing_object->pager,
+                       (backing_offset + backing_object->paging_offset));
+       }
+}
+
 /*
  *     Routine:        vm_object_do_collapse
  *     Purpose:
@@ -4691,6 +4956,9 @@ vm_object_do_collapse(
        vm_object_lock_assert_exclusive(object);
        vm_object_lock_assert_exclusive(backing_object);
 
+       assert(object->purgable == VM_PURGABLE_DENY);
+       assert(backing_object->purgable == VM_PURGABLE_DENY);
+
        backing_offset = object->vo_shadow_offset;
        size = object->vo_size;
 
@@ -4701,9 +4969,9 @@ vm_object_do_collapse(
         *      pages that shadow them.
         */
        
-       while (!queue_empty(&backing_object->memq)) {
+       while (!vm_page_queue_empty(&backing_object->memq)) {
                
-               p = (vm_page_t) queue_first(&backing_object->memq);
+               p = (vm_page_t) vm_page_queue_first(&backing_object->memq);
                
                new_offset = (p->offset - backing_offset);
                
@@ -4735,30 +5003,25 @@ vm_object_do_collapse(
                        pp = vm_page_lookup(object, new_offset);
                        if (pp == VM_PAGE_NULL) {
 
-                               /*
-                                *      Parent now has no page.
-                                *      Move the backing object's page up.
-                                */
-
-                               vm_page_rename(p, object, new_offset, TRUE);
-#if    MACH_PAGEMAP
-                       } else if (pp->absent) {
-
-                               /*
-                                *      Parent has an absent page...
-                                *      it's not being paged in, so
-                                *      it must really be missing from
-                                *      the parent.
-                                *
-                                *      Throw out the absent page...
-                                *      any faults looking for that
-                                *      page will restart with the new
-                                *      one.
-                                */
-
-                               VM_PAGE_FREE(pp);
-                               vm_page_rename(p, object, new_offset, TRUE);
-#endif /* MACH_PAGEMAP */
+                               if (VM_COMPRESSOR_PAGER_STATE_GET(object,
+                                                                 new_offset)
+                                   == VM_EXTERNAL_STATE_EXISTS) {
+                                       /*
+                                        * Parent object has this page
+                                        * in the VM compressor.
+                                        * Throw away the backing
+                                        * object's page.
+                                        */
+                                       VM_PAGE_FREE(p);
+                               } else {
+                                       /*
+                                        *      Parent now has no page.
+                                        *      Move the backing object's page
+                                        *      up.
+                                        */
+                                       vm_page_rename(p, object, new_offset,
+                                                      TRUE);
+                               }
                        } else {
                                assert(! pp->absent);
 
@@ -4771,26 +5034,21 @@ vm_object_do_collapse(
                        }
                }
        }
-       
-#if    !MACH_PAGEMAP
-       assert((!object->pager_created && (object->pager == MEMORY_OBJECT_NULL))
-               || (!backing_object->pager_created
-               &&  (backing_object->pager == MEMORY_OBJECT_NULL)));
-#else 
-        assert(!object->pager_created && object->pager == MEMORY_OBJECT_NULL);
-#endif /* !MACH_PAGEMAP */
 
-       if (backing_object->pager != MEMORY_OBJECT_NULL) {
-               vm_object_hash_entry_t  entry;
+       if (vm_object_collapse_compressor_allowed &&
+           object->pager != MEMORY_OBJECT_NULL &&
+           backing_object->pager != MEMORY_OBJECT_NULL) {
 
-#if 00
-               if (COMPRESSED_PAGER_IS_ACTIVE) {
-                       panic("vm_object_do_collapse(%p,%p): "
-                             "backing_object has a compressor pager",
-                             object, backing_object);
-               }
-#endif
+               /* move compressed pages from backing_object to object */
+               vm_object_do_collapse_compressor(object, backing_object);
+
+       } else if (backing_object->pager != MEMORY_OBJECT_NULL) {
+               vm_object_hash_entry_t  entry;
 
+               assert((!object->pager_created &&
+                       (object->pager == MEMORY_OBJECT_NULL)) ||
+                      (!backing_object->pager_created &&
+                       (backing_object->pager == MEMORY_OBJECT_NULL)));
                /*
                 *      Move the pager from backing_object to object.
                 *
@@ -4801,6 +5059,8 @@ vm_object_do_collapse(
 
                assert(!object->paging_in_progress);
                assert(!object->activity_in_progress);
+               assert(!object->pager_created);
+               assert(object->pager == NULL);
                object->pager = backing_object->pager;
 
                if (backing_object->hashed) {
@@ -4824,34 +5084,13 @@ vm_object_do_collapse(
                        memory_object_control_collapse(object->pager_control,
                                                       object);
                }
+               /* the backing_object has lost its pager: reset all fields */
+               backing_object->pager_created = FALSE;
+               backing_object->pager_control = NULL;
+               backing_object->pager_ready = FALSE;
+               backing_object->paging_offset = 0;
+               backing_object->pager = NULL;
        }
-
-#if    MACH_PAGEMAP
-       /*
-        *      If the shadow offset is 0, the use the existence map from
-        *      the backing object if there is one. If the shadow offset is
-        *      not zero, toss it.
-        *
-        *      XXX - If the shadow offset is not 0 then a bit copy is needed
-        *      if the map is to be salvaged.  For now, we just just toss the
-        *      old map, giving the collapsed object no map. This means that
-        *      the pager is invoked for zero fill pages.  If analysis shows
-        *      that this happens frequently and is a performance hit, then
-        *      this code should be fixed to salvage the map.
-        */
-       assert(object->existence_map == VM_EXTERNAL_NULL);
-       if (backing_offset || (size != backing_object->vo_size)) {
-               vm_external_discarded++;
-               vm_external_destroy(backing_object->existence_map,
-                       backing_object->vo_size);
-       }
-       else {
-               vm_external_collapsed++;
-               object->existence_map = backing_object->existence_map;
-       }
-       backing_object->existence_map = VM_EXTERNAL_NULL;
-#endif /* MACH_PAGEMAP */
-
        /*
         *      Object now shadows whatever backing_object did.
         *      Note that the reference to backing_object->shadow
@@ -4863,6 +5102,9 @@ vm_object_do_collapse(
        object->shadow = backing_object->shadow;
        if (object->shadow) {
                object->vo_shadow_offset += backing_object->vo_shadow_offset;
+               /* "backing_object" gave its shadow to "object" */
+               backing_object->shadow = VM_OBJECT_NULL;
+               backing_object->vo_shadow_offset = 0;
        } else {
                /* no shadow, therefore no shadow offset... */
                object->vo_shadow_offset = 0;
@@ -4877,11 +5119,25 @@ vm_object_do_collapse(
         *      pager left, and no object references within it,
         *      all that is necessary is to dispose of it.
         */
+       object_collapses++;
        
-       assert((backing_object->ref_count == 1) &&
-              (backing_object->resident_page_count == 0) &&
-              (backing_object->paging_in_progress == 0) &&
-              (backing_object->activity_in_progress == 0));
+       assert(backing_object->ref_count == 1);
+       assert(backing_object->resident_page_count == 0);
+       assert(backing_object->paging_in_progress == 0);
+       assert(backing_object->activity_in_progress == 0);
+       assert(backing_object->shadow == VM_OBJECT_NULL);
+       assert(backing_object->vo_shadow_offset == 0);
+
+       if (backing_object->pager != MEMORY_OBJECT_NULL) {
+               /* ... unless it has a pager; need to terminate pager too */
+               vm_counters.do_collapse_terminate++;
+               if (vm_object_terminate(backing_object) != KERN_SUCCESS) {
+                       vm_counters.do_collapse_terminate_failure++;
+               }
+               return;
+       }
+
+       assert(backing_object->pager == NULL);
 
        backing_object->alive = FALSE;
        vm_object_unlock(backing_object);
@@ -4889,11 +5145,17 @@ vm_object_do_collapse(
        XPR(XPR_VM_OBJECT, "vm_object_collapse, collapsed 0x%X\n",
                backing_object, 0,0,0,0);
 
+#if VM_OBJECT_TRACKING
+       if (vm_object_tracking_inited) {
+               btlog_remove_entries_for_element(vm_object_tracking_btlog,
+                                                backing_object);
+       }
+#endif /* VM_OBJECT_TRACKING */
+
        vm_object_lock_destroy(backing_object);
 
        zfree(vm_object_zone, backing_object);
        
-       object_collapses++;
 }
 
 static void
@@ -5042,13 +5304,13 @@ static unsigned long vm_object_collapse_do_bypass = 0;
 
 __private_extern__ void
 vm_object_collapse(
-       register vm_object_t                    object,
-       register vm_object_offset_t             hint_offset,
+       vm_object_t                             object,
+       vm_object_offset_t                      hint_offset,
        boolean_t                               can_bypass)
 {
-       register vm_object_t                    backing_object;
-       register unsigned int                   rcount;
-       register unsigned int                   size;
+       vm_object_t                             backing_object;
+       unsigned int                            rcount;
+       unsigned int                            size;
        vm_object_t                             original_object;
        int                                     object_lock_type;
        int                                     backing_object_lock_type;
@@ -5140,6 +5402,29 @@ retry:
                        object_lock_type = backing_object_lock_type;
                        continue;
                }
+
+               /*
+                * Purgeable objects are not supposed to engage in
+                * copy-on-write activities, so should not have
+                * any shadow objects or be a shadow object to another
+                * object.
+                * Collapsing a purgeable object would require some
+                * updates to the purgeable compressed ledgers.
+                */
+               if (object->purgable != VM_PURGABLE_DENY ||
+                   backing_object->purgable != VM_PURGABLE_DENY) {
+                       panic("vm_object_collapse() attempting to collapse "
+                             "purgeable object: %p(%d) %p(%d)\n",
+                             object, object->purgable,
+                             backing_object, backing_object->purgable);
+                       /* try and collapse the rest of the shadow chain */
+                       if (object != original_object) {
+                               vm_object_unlock(object);
+                       }
+                       object = backing_object;
+                       object_lock_type = backing_object_lock_type;
+                       continue;
+               }
        
                /*
                 *      The backing object can't be a copy-object:
@@ -5172,21 +5457,13 @@ retry:
                 *      object, we may be able to collapse it into the
                 *      parent.
                 *
-                *      If MACH_PAGEMAP is defined:
-                *      The parent must not have a pager created for it,
-                *      since collapsing a backing_object dumps new pages
-                *      into the parent that its pager doesn't know about
-                *      (and the collapse code can't merge the existence
-                *      maps).
-                *      Otherwise:
                 *      As long as one of the objects is still not known
                 *      to the pager, we can collapse them.
                 */
                if (backing_object->ref_count == 1 &&
-                   (!object->pager_created 
-#if    !MACH_PAGEMAP
+                   (vm_object_collapse_compressor_allowed ||
+                    !object->pager_created 
                     || (!backing_object->pager_created)
-#endif /*!MACH_PAGEMAP */
                    ) && vm_object_collapse_allowed) {
 
                        /*
@@ -5265,11 +5542,7 @@ retry:
                         *      then we cannot bypass it, because we don't know
                         *      what pages it has.
                         */
-                       if (backing_object->pager_created
-#if    MACH_PAGEMAP
-                           && (backing_object->existence_map == VM_EXTERNAL_NULL)
-#endif /* MACH_PAGEMAP */
-                               ) {
+                       if (backing_object->pager_created) {
                                /* try and collapse the rest of the shadow chain */
                                if (object != original_object) {
                                        vm_object_unlock(object);
@@ -5284,11 +5557,7 @@ retry:
                         *      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 */
-                               ) {
+                       if (object->pager_created) {
                                /* try and collapse the rest of the shadow chain */
                                if (object != original_object) {
                                        vm_object_unlock(object);
@@ -5329,20 +5598,10 @@ retry:
                         *
                         */
 
-#if    MACH_PAGEMAP
-#define EXISTS_IN_OBJECT(obj, off, rc) \
-       ((vm_external_state_get((obj)->existence_map,   \
-                               (vm_offset_t)(off))     \
-         == VM_EXTERNAL_STATE_EXISTS) ||               \
-        (VM_COMPRESSOR_PAGER_STATE_GET((obj), (off))   \
-         == VM_EXTERNAL_STATE_EXISTS) ||               \
-        ((rc) && vm_page_lookup((obj), (off)) != VM_PAGE_NULL && (rc)--))
-#else  /* MACH_PAGEMAP */
 #define EXISTS_IN_OBJECT(obj, off, rc)                 \
        ((VM_COMPRESSOR_PAGER_STATE_GET((obj), (off))   \
          == VM_EXTERNAL_STATE_EXISTS) ||               \
         ((rc) && vm_page_lookup((obj), (off)) != VM_PAGE_NULL && (rc)--))
-#endif /* MACH_PAGEMAP */
 
                        /*
                         * Check the hint location first
@@ -5387,7 +5646,7 @@ retry:
                                vm_page_t p;
 
                                backing_rcount = backing_object->resident_page_count;
-                               p = (vm_page_t)queue_first(&backing_object->memq);
+                               p = (vm_page_t)vm_page_queue_first(&backing_object->memq);
                                do {
                                        offset = (p->offset - backing_offset);
 
@@ -5399,7 +5658,7 @@ retry:
                                                
                                                break;
                                        }
-                                       p = (vm_page_t) queue_next(&p->listq);
+                                       p = (vm_page_t) vm_page_queue_next(&p->listq);
 
                                } while (--backing_rcount);
                                if (backing_rcount != 0 ) {
@@ -5417,11 +5676,7 @@ retry:
                         * Walk through the offsets looking for pages in the
                         * backing object that show through to the object.
                         */
-                       if (backing_rcount
-#if MACH_PAGEMAP
-                           || backing_object->existence_map
-#endif /* MACH_PAGEMAP */
-                               ) {
+                       if (backing_rcount) {
                                offset = hint_offset;
                                
                                while((offset =
@@ -5479,9 +5734,12 @@ retry:
                continue;
        }
 
+       /* NOT REACHED */
+       /*
        if (object != original_object) {
                vm_object_unlock(object);
        }
+       */
 }
 
 /*
@@ -5500,11 +5758,11 @@ unsigned int vm_object_page_remove_iterate = 0;
 
 __private_extern__ void
 vm_object_page_remove(
-       register vm_object_t            object,
-       register vm_object_offset_t     start,
-       register vm_object_offset_t     end)
+       vm_object_t             object,
+       vm_object_offset_t      start,
+       vm_object_offset_t      end)
 {
-       register vm_page_t      p, next;
+       vm_page_t       p, next;
 
        /*
         *      One and two page removals are most popular.
@@ -5518,22 +5776,22 @@ vm_object_page_remove(
                for (; start < end; start += PAGE_SIZE_64) {
                        p = vm_page_lookup(object, start);
                        if (p != VM_PAGE_NULL) {
-                               assert(!p->cleaning && !p->pageout && !p->laundry);
+                               assert(!p->cleaning && !p->laundry);
                                if (!p->fictitious && p->pmapped)
-                                       pmap_disconnect(p->phys_page);
+                                       pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(p));
                                VM_PAGE_FREE(p);
                        }
                }
        } else {
                vm_object_page_remove_iterate++;
 
-               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);
+               p = (vm_page_t) vm_page_queue_first(&object->memq);
+               while (!vm_page_queue_end(&object->memq, (vm_page_queue_entry_t) p)) {
+                       next = (vm_page_t) vm_page_queue_next(&p->listq);
                        if ((start <= p->offset) && (p->offset < end)) {
-                               assert(!p->cleaning && !p->pageout && !p->laundry);
+                               assert(!p->cleaning && !p->laundry);
                                if (!p->fictitious && p->pmapped)
-                                       pmap_disconnect(p->phys_page);
+                                       pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(p));
                                VM_PAGE_FREE(p);
                        }
                        p = next;
@@ -5569,7 +5827,7 @@ static int vm_object_coalesce_count = 0;
 
 __private_extern__ boolean_t
 vm_object_coalesce(
-       register vm_object_t            prev_object,
+       vm_object_t                     prev_object,
        vm_object_t                     next_object,
        vm_object_offset_t              prev_offset,
        __unused vm_object_offset_t next_offset,
@@ -5639,18 +5897,6 @@ vm_object_coalesce(
         */
        newsize = prev_offset + prev_size + next_size;
        if (newsize > prev_object->vo_size) {
-#if    MACH_PAGEMAP
-               /*
-                *      We cannot extend an object that has existence info,
-                *      since the existence info might then fail to cover
-                *      the entire object.
-                *
-                *      This assertion must be true because the object
-                *      has no pager, and we only create existence info
-                *      for objects with pagers.
-                */
-               assert(prev_object->existence_map == VM_EXTERNAL_NULL);
-#endif /* MACH_PAGEMAP */
                prev_object->vo_size = newsize;
        }
 
@@ -5658,59 +5904,6 @@ vm_object_coalesce(
        return(TRUE);
 }
 
-/*
- *     Attach a set of physical pages to an object, so that they can
- *     be mapped by mapping the object.  Typically used to map IO memory.
- *
- *     The mapping function and its private data are used to obtain the
- *     physical addresses for each page to be mapped.
- */
-void
-vm_object_page_map(
-       vm_object_t             object,
-       vm_object_offset_t      offset,
-       vm_object_size_t        size,
-       vm_object_offset_t      (*map_fn)(void *map_fn_data, 
-               vm_object_offset_t offset),
-               void            *map_fn_data)   /* private to map_fn */
-{
-       int64_t num_pages;
-       int     i;
-       vm_page_t       m;
-       vm_page_t       old_page;
-       vm_object_offset_t      addr;
-
-       num_pages = atop_64(size);
-
-       for (i = 0; i < num_pages; i++, offset += PAGE_SIZE_64) {
-
-           addr = (*map_fn)(map_fn_data, offset);
-
-           while ((m = vm_page_grab_fictitious()) == VM_PAGE_NULL)
-               vm_page_more_fictitious();
-
-           vm_object_lock(object);
-           if ((old_page = vm_page_lookup(object, offset))
-                       != VM_PAGE_NULL)
-           {
-                   VM_PAGE_FREE(old_page);
-           }
-
-           assert((ppnum_t) addr == addr);
-           vm_page_init(m, (ppnum_t) addr, FALSE);
-           /*
-            * 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);
-
-           PAGE_WAKEUP_DONE(m);
-           vm_object_unlock(object);
-       }
-}
-
 kern_return_t
 vm_object_populate_with_private(
                vm_object_t             object,
@@ -5743,16 +5936,16 @@ vm_object_populate_with_private(
 
                        if (m != VM_PAGE_NULL) {
                                if (m->fictitious) {
-                                       if (m->phys_page != vm_page_guard_addr) {
+                                       if (VM_PAGE_GET_PHYS_PAGE(m) != vm_page_guard_addr) {
 
                                                vm_page_lockspin_queues();
                                                m->private = TRUE;
                                                vm_page_unlock_queues();
 
                                                m->fictitious = FALSE;
-                                               m->phys_page = base_page;
+                                               VM_PAGE_SET_PHYS_PAGE(m, base_page);
                                        }
-                               } else if (m->phys_page != base_page) {
+                               } else if (VM_PAGE_GET_PHYS_PAGE(m) != base_page) {
 
                                        if ( !m->private) {
                                                /*
@@ -5764,9 +5957,9 @@ vm_object_populate_with_private(
                                                /*
                                                 * pmap call to clear old mapping
                                                 */
-                                               pmap_disconnect(m->phys_page);
+                                               pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(m));
                                        }
-                                       m->phys_page = base_page;
+                                       VM_PAGE_SET_PHYS_PAGE(m, base_page);
                                }
                                if (m->encrypted) {
                                        /*
@@ -5785,7 +5978,7 @@ vm_object_populate_with_private(
                                 */
                                m->private = TRUE;
                                m->fictitious = FALSE;
-                               m->phys_page = base_page;
+                               VM_PAGE_SET_PHYS_PAGE(m, base_page);
                                m->unusual = TRUE;
                                m->busy = FALSE;
 
@@ -5833,7 +6026,7 @@ memory_object_free_from_cache(
 #if VM_OBJECT_CACHE
        int     object_released = 0;
 
-       register vm_object_t object = VM_OBJECT_NULL;
+       vm_object_t object = VM_OBJECT_NULL;
        vm_object_t shadow;
 
 /*
@@ -6176,8 +6369,12 @@ vm_object_lock_request(
  * purgeable with no delayed copies pending.
  */
 void
-vm_object_purge(vm_object_t object)
+vm_object_purge(vm_object_t object, int flags)
 {
+       unsigned int    object_page_count = 0;
+       unsigned int    pgcount = 0;
+       boolean_t       skipped_object = FALSE;
+
         vm_object_lock_assert_exclusive(object);
 
        if (object->purgable == VM_PURGABLE_DENY)
@@ -6186,7 +6383,22 @@ vm_object_purge(vm_object_t object)
        assert(object->copy == VM_OBJECT_NULL);
        assert(object->copy_strategy == MEMORY_OBJECT_COPY_NONE);
 
-       if(object->purgable == VM_PURGABLE_VOLATILE) {
+       /*
+        * We need to set the object's state to VM_PURGABLE_EMPTY *before*
+        * reaping its pages.  We update vm_page_purgeable_count in bulk
+        * and we don't want vm_page_remove() to update it again for each
+        * page we reap later.
+        *
+        * For the purgeable ledgers, pages from VOLATILE and EMPTY objects
+        * are all accounted for in the "volatile" ledgers, so this does not
+        * make any difference.
+        * If we transitioned directly from NONVOLATILE to EMPTY,
+        * vm_page_purgeable_count must have been updated when the object
+        * was dequeued from its volatile queue and the purgeable ledgers
+        * must have also been updated accordingly at that time (in
+        * vm_object_purgable_control()).
+        */
+       if (object->purgable == VM_PURGABLE_VOLATILE) {
                unsigned int delta;
                assert(object->resident_page_count >=
                       object->wired_page_count);
@@ -6204,10 +6416,74 @@ vm_object_purge(vm_object_t object)
                        OSAddAtomic(-object->wired_page_count,
                                    (SInt32 *)&vm_page_purgeable_wired_count);
                }
+               object->purgable = VM_PURGABLE_EMPTY;
        }
-       object->purgable = VM_PURGABLE_EMPTY;
+       assert(object->purgable == VM_PURGABLE_EMPTY);
        
+       object_page_count = object->resident_page_count;
+
        vm_object_reap_pages(object, REAP_PURGEABLE);
+
+       if (object->pager != NULL) {
+
+               assert(VM_CONFIG_COMPRESSOR_IS_PRESENT);
+
+               if (object->activity_in_progress == 0 &&
+                   object->paging_in_progress == 0) {
+                       /*
+                        * Also reap any memory coming from this object
+                        * in the VM compressor.
+                        *
+                        * There are no operations in progress on the VM object
+                        * and no operation can start while we're holding the
+                        * VM object lock, so it's safe to reap the compressed
+                        * pages and update the page counts.
+                        */
+                       pgcount = vm_compressor_pager_get_count(object->pager);
+                       if (pgcount) {
+                               pgcount = vm_compressor_pager_reap_pages(object->pager, flags);
+                               vm_compressor_pager_count(object->pager,
+                                                         -pgcount,
+                                                         FALSE, /* shared */
+                                                         object);
+                               vm_purgeable_compressed_update(object,
+                                                              -pgcount);
+                       }
+                       if ( !(flags & C_DONT_BLOCK)) {
+                               assert(vm_compressor_pager_get_count(object->pager)
+                                      == 0);
+                       }
+               } else {
+                       /*
+                        * There's some kind of paging activity in progress
+                        * for this object, which could result in a page
+                        * being compressed or decompressed, possibly while
+                        * the VM object is not locked, so it could race
+                        * with us.
+                        *
+                        * We can't really synchronize this without possibly 
+                        * causing a deadlock when the compressor needs to
+                        * allocate or free memory while compressing or
+                        * decompressing a page from a purgeable object
+                        * mapped in the kernel_map...
+                        *
+                        * So let's not attempt to purge the compressor
+                        * pager if there's any kind of operation in
+                        * progress on the VM object.
+                        */
+                       skipped_object = TRUE;
+               }
+       }
+
+       vm_object_lock_assert_exclusive(object);
+
+       KERNEL_DEBUG_CONSTANT_IST(KDEBUG_TRACE, (MACHDBG_CODE(DBG_MACH_VM, OBJECT_PURGE_ONE)),
+                             VM_KERNEL_UNSLIDE_OR_PERM(object), /* purged object */
+                             object_page_count,
+                             pgcount,
+                             skipped_object,
+                             0);
+
 }
                                
 
@@ -6302,6 +6578,8 @@ vm_object_purgable_control(
                return KERN_INVALID_ARGUMENT;
        }
 
+       vm_object_lock_assert_exclusive(object);
+
        /*
         * Get current state of the purgeable object.
         */
@@ -6362,8 +6640,16 @@ vm_object_purgable_control(
 
                        vm_page_lock_queues();
 
-                       assert(object->objq.next != NULL && object->objq.prev != NULL); /* object should be on a queue */
-                       purgeable_q_t queue = vm_purgeable_object_remove(object);
+                       /* object should be on a queue */
+                       assert(object->objq.next != NULL &&
+                              object->objq.prev != NULL);
+                       purgeable_q_t queue;
+
+                       /*
+                        * Move object from its volatile queue to the
+                        * non-volatile queue...
+                        */
+                       queue = vm_purgeable_object_remove(object);
                        assert(queue);
 
                        if (object->purgeable_when_ripe) {
@@ -6373,6 +6659,16 @@ vm_object_purgable_control(
 
                        vm_page_unlock_queues();
                }
+               if (old_state == VM_PURGABLE_VOLATILE ||
+                   old_state == VM_PURGABLE_EMPTY) {
+                       /*
+                        * Transfer the object's pages from the volatile to
+                        * non-volatile ledgers.
+                        */
+                       vm_purgeable_accounting(object, VM_PURGABLE_VOLATILE,
+                                               FALSE);
+               }
+
                break;
 
        case VM_PURGABLE_VOLATILE:
@@ -6380,13 +6676,13 @@ vm_object_purgable_control(
                        vm_page_t       p;
                        int             refmod;
 
-                       queue_iterate(&object->memq, p, vm_page_t, listq) {
+                       vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
                                if (p->busy ||
                                    VM_PAGE_WIRED(p) ||
                                    p->fictitious) {
                                        continue;
                                }
-                               refmod = pmap_disconnect(p->phys_page);
+                               refmod = pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(p));
                                if ((refmod & VM_MEM_MODIFIED) &&
                                    !p->dirty) {
                                        SET_PAGE_DIRTY(p, FALSE);
@@ -6395,7 +6691,8 @@ vm_object_purgable_control(
                }
                                               
                if (old_state == VM_PURGABLE_EMPTY &&
-                   object->resident_page_count == 0)
+                   object->resident_page_count == 0 &&
+                   object->pager == NULL)
                        break;
 
                purgeable_q_t queue;
@@ -6451,8 +6748,9 @@ vm_object_purgable_control(
 
                        object->purgable = new_state;
 
-                       /* object should not be on a queue */
-                       assert(object->objq.next == NULL && object->objq.prev == NULL);
+                       /* object should be on "non-volatile" queue */
+                       assert(object->objq.next != NULL);
+                       assert(object->objq.prev != NULL);
                }
                else if (old_state == VM_PURGABLE_VOLATILE) {
                        purgeable_q_t   old_queue;
@@ -6498,6 +6796,10 @@ vm_object_purgable_control(
                        }
                };
                vm_purgeable_object_add(object, queue, (*state&VM_VOLATILE_GROUP_MASK)>>VM_VOLATILE_GROUP_SHIFT );
+               if (old_state == VM_PURGABLE_NONVOLATILE) {
+                       vm_purgeable_accounting(object, VM_PURGABLE_NONVOLATILE,
+                                               FALSE);
+               }
 
                assert(queue->debug_count_objects>=0);
         
@@ -6509,13 +6811,13 @@ vm_object_purgable_control(
                        vm_page_t       p;
                        int             refmod;
 
-                       queue_iterate(&object->memq, p, vm_page_t, listq) {
+                       vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
                                if (p->busy ||
                                    VM_PAGE_WIRED(p) ||
                                    p->fictitious) {
                                        continue;
                                }
-                               refmod = pmap_disconnect(p->phys_page);
+                               refmod = pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(p));
                                if ((refmod & VM_MEM_MODIFIED) &&
                                    !p->dirty) {
                                        SET_PAGE_DIRTY(p, FALSE);
@@ -6523,37 +6825,63 @@ vm_object_purgable_control(
                        }
                }
 
-               if (old_state != new_state) {
-                       assert(old_state == VM_PURGABLE_NONVOLATILE ||
-                              old_state == VM_PURGABLE_VOLATILE);
-                       if (old_state == VM_PURGABLE_VOLATILE) {
-                               purgeable_q_t old_queue;
-
-                               /* object should be on a queue */
-                               assert(object->objq.next != NULL &&
-                                      object->objq.prev != NULL);
-                               old_queue = vm_purgeable_object_remove(object);
-                               assert(old_queue);
-                               if (object->purgeable_when_ripe) {
-                                       vm_page_lock_queues();
-                                       vm_purgeable_token_delete_first(old_queue);
-                                       vm_page_unlock_queues();
-                               }
-                       }
-                       (void) vm_object_purge(object);
+               if (old_state == new_state) {
+                       /* nothing changes */
+                       break;
                }
-               break;
 
-       }
-       *state = old_state;
+               assert(old_state == VM_PURGABLE_NONVOLATILE ||
+                      old_state == VM_PURGABLE_VOLATILE);
+               if (old_state == VM_PURGABLE_VOLATILE) {
+                       purgeable_q_t old_queue;
 
-       return KERN_SUCCESS;
-}
+                       /* object should be on a queue */
+                       assert(object->objq.next != NULL &&
+                              object->objq.prev != NULL);
 
-kern_return_t
-vm_object_get_page_counts(
-       vm_object_t             object,
-       vm_object_offset_t      offset,
+                       old_queue = vm_purgeable_object_remove(object);
+                       assert(old_queue);
+                       if (object->purgeable_when_ripe) {
+                               vm_page_lock_queues();
+                               vm_purgeable_token_delete_first(old_queue);
+                               vm_page_unlock_queues();
+                       }
+               }
+
+               if (old_state == VM_PURGABLE_NONVOLATILE) {
+                       /*
+                        * This object's pages were previously accounted as
+                        * "non-volatile" and now need to be accounted as
+                        * "volatile".
+                        */
+                       vm_purgeable_accounting(object, VM_PURGABLE_NONVOLATILE,
+                                               FALSE);
+                       /*
+                        * Set to VM_PURGABLE_EMPTY because the pages are no
+                        * longer accounted in the "non-volatile" ledger
+                        * and are also not accounted for in
+                        * "vm_page_purgeable_count".
+                        */
+                       object->purgable = VM_PURGABLE_EMPTY;
+               }
+
+               (void) vm_object_purge(object, 0);
+               assert(object->purgable == VM_PURGABLE_EMPTY);
+
+               break;
+       }
+
+       *state = old_state;
+
+       vm_object_lock_assert_exclusive(object);
+
+       return KERN_SUCCESS;
+}
+
+kern_return_t
+vm_object_get_page_counts(
+       vm_object_t             object,
+       vm_object_offset_t      offset,
        vm_object_size_t        size,
        unsigned int            *resident_page_count,
        unsigned int            *dirty_page_count)
@@ -6597,7 +6925,7 @@ vm_object_get_page_counts(
 
        if (object->resident_page_count <= (size >> PAGE_SHIFT)) {
 
-               queue_iterate(&object->memq, p, vm_page_t, listq) {
+               vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
                
                        if (p->offset >= cur_offset && p->offset < end_offset) {
 
@@ -6605,7 +6933,7 @@ vm_object_get_page_counts(
 
                                if (count_dirty_pages) {
                                        
-                                       if (p->dirty || (p->wpmapped && pmap_is_modified(p->phys_page))) {
+                                       if (p->dirty || (p->wpmapped && pmap_is_modified(VM_PAGE_GET_PHYS_PAGE(p)))) {
                                                
                                                local_dirty_count++;
                                        }
@@ -6624,7 +6952,7 @@ vm_object_get_page_counts(
 
                                if (count_dirty_pages) {
                                        
-                                       if (p->dirty || (p->wpmapped && pmap_is_modified(p->phys_page))) {
+                                       if (p->dirty || (p->wpmapped && pmap_is_modified(VM_PAGE_GET_PHYS_PAGE(p)))) {
                                
                                                local_dirty_count++;
                                        }
@@ -6739,7 +7067,7 @@ vm_object_res_reference(
 #endif
 __private_extern__ void
 vm_object_reference(
-       register vm_object_t    object)
+       vm_object_t     object)
 {
        if (object == VM_OBJECT_NULL)
                return;
@@ -6896,52 +7224,52 @@ vm_object_transpose(
         * Transpose the lists of resident pages.
         * This also updates the resident_page_count and the memq_hint.
         */
-       if (object1->phys_contiguous || queue_empty(&object1->memq)) {
+       if (object1->phys_contiguous || vm_page_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);
+               while (!vm_page_queue_empty(&object2->memq)) {
+                       page = (vm_page_t) vm_page_queue_first(&object2->memq);
                        vm_page_rename(page, object1, page->offset, FALSE);
                }
-               assert(queue_empty(&object2->memq));
-       } else if (object2->phys_contiguous || queue_empty(&object2->memq)) {
+               assert(vm_page_queue_empty(&object2->memq));
+       } else if (object2->phys_contiguous || vm_page_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);
+               while (!vm_page_queue_empty(&object1->memq)) {
+                       page = (vm_page_t) vm_page_queue_first(&object1->memq);
                        vm_page_rename(page, object2, page->offset, FALSE);
                }
-               assert(queue_empty(&object1->memq));
+               assert(vm_page_queue_empty(&object1->memq));
        } else {
                /* transfer object1's pages to tmp_object */
-               while (!queue_empty(&object1->memq)) {
-                       page = (vm_page_t) queue_first(&object1->memq);
+               while (!vm_page_queue_empty(&object1->memq)) {
+                       page = (vm_page_t) vm_page_queue_first(&object1->memq);
                        page_offset = page->offset;
                        vm_page_remove(page, TRUE);
                        page->offset = page_offset;
-                       queue_enter(&tmp_object->memq, page, vm_page_t, listq);
+                       vm_page_queue_enter(&tmp_object->memq, page, vm_page_t, listq);
                }
-               assert(queue_empty(&object1->memq));
+               assert(vm_page_queue_empty(&object1->memq));
                /* transfer object2's pages to object1 */
-               while (!queue_empty(&object2->memq)) {
-                       page = (vm_page_t) queue_first(&object2->memq);
+               while (!vm_page_queue_empty(&object2->memq)) {
+                       page = (vm_page_t) vm_page_queue_first(&object2->memq);
                        vm_page_rename(page, object1, page->offset, FALSE);
                }
-               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);
+               assert(vm_page_queue_empty(&object2->memq));
+               /* transfer tmp_object's pages to object2 */
+               while (!vm_page_queue_empty(&tmp_object->memq)) {
+                       page = (vm_page_t) vm_page_queue_first(&tmp_object->memq);
+                       vm_page_queue_remove(&tmp_object->memq, page,
+                                            vm_page_t, listq);
                        vm_page_insert(page, object2, page->offset);
                }
-               assert(queue_empty(&tmp_object->memq));
+               assert(vm_page_queue_empty(&tmp_object->memq));
        }
 
 #define __TRANSPOSE_FIELD(field)                               \
@@ -7028,9 +7356,6 @@ MACRO_END
        __TRANSPOSE_FIELD(pages_created);
        __TRANSPOSE_FIELD(pages_used);
        __TRANSPOSE_FIELD(scan_collisions);
-#if MACH_PAGEMAP
-       __TRANSPOSE_FIELD(existence_map);
-#endif
        __TRANSPOSE_FIELD(cow_hint);
 #if MACH_ASSERT
        __TRANSPOSE_FIELD(paging_object);
@@ -7066,10 +7391,10 @@ MACRO_END
 #if UPL_DEBUG
        /* "uplq" refers to the object not its contents (see upl_transpose()) */
 #endif
-       assert(object1->objq.next == NULL);
-       assert(object1->objq.prev == NULL);
-       assert(object2->objq.next == NULL);
-       assert(object2->objq.prev == NULL);
+       assert((object1->purgable == VM_PURGABLE_DENY) || (object1->objq.next == NULL));
+       assert((object1->purgable == VM_PURGABLE_DENY) || (object1->objq.prev == NULL));
+       assert((object2->purgable == VM_PURGABLE_DENY) || (object2->objq.next == NULL));
+       assert((object2->purgable == VM_PURGABLE_DENY) || (object2->objq.prev == NULL));
 
 #undef __TRANSPOSE_FIELD
 
@@ -7121,11 +7446,15 @@ done:
 extern int speculative_reads_disabled;
 extern int ignore_is_ssd;
 
-unsigned int preheat_pages_max = MAX_UPL_TRANSFER;
-unsigned int preheat_pages_min = 8;
-
-uint32_t pre_heat_scaling[MAX_UPL_TRANSFER + 1];
-uint32_t pre_heat_cluster[MAX_UPL_TRANSFER + 1];
+/*
+ * Try to always keep these values an even multiple of PAGE_SIZE. We use these values
+ * to derive min_ph_bytes and max_ph_bytes (IMP: bytes not # of pages) and expect those values to
+ * always be page-aligned. The derivation could involve operations (e.g. division)
+ * that could give us non-page-size aligned values if we start out with values that
+ * are odd multiples of PAGE_SIZE.
+ */
+       unsigned int preheat_max_bytes = MAX_UPL_TRANSFER_BYTES;
+unsigned int preheat_min_bytes = (1024 * 32);
 
 
 __private_extern__ void
@@ -7148,9 +7477,8 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
        uint32_t                throttle_limit;
        int                     sequential_run;
        int                     sequential_behavior = VM_BEHAVIOR_SEQUENTIAL;
-       unsigned int            max_ph_size;
-       unsigned int            min_ph_size;
-       unsigned int            min_ph_size_in_bytes;
+       vm_size_t               max_ph_size;
+       vm_size_t               min_ph_size;
 
        assert( !(*length & PAGE_MASK));
        assert( !(*start & PAGE_MASK_64));
@@ -7186,29 +7514,36 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
        if (!ignore_is_ssd)
                vnode_pager_get_isSSD(object->pager, &isSSD);
 
-       min_ph_size = preheat_pages_min;
-       max_ph_size = preheat_pages_max;
+       min_ph_size = round_page(preheat_min_bytes);
+       max_ph_size = round_page(preheat_max_bytes);
 
        if (isSSD) {
                min_ph_size /= 2;
                max_ph_size /= 8;
+
+               if (min_ph_size & PAGE_MASK_64) {
+                       min_ph_size = trunc_page(min_ph_size);
+               }
+
+               if (max_ph_size & PAGE_MASK_64) {
+                       max_ph_size = trunc_page(max_ph_size);
+               }
        }
-       if (min_ph_size < 1)
-               min_ph_size = 1;
 
-       if (max_ph_size < 1)
-               max_ph_size = 1;
-       else if (max_ph_size > MAX_UPL_TRANSFER)
-               max_ph_size = MAX_UPL_TRANSFER;
+       if (min_ph_size < PAGE_SIZE)
+               min_ph_size = PAGE_SIZE;
+
+       if (max_ph_size < PAGE_SIZE)
+               max_ph_size = PAGE_SIZE;
+       else if (max_ph_size > MAX_UPL_TRANSFER_BYTES)
+               max_ph_size = MAX_UPL_TRANSFER_BYTES;
 
-       if (max_length > (max_ph_size * PAGE_SIZE)
-               max_length = max_ph_size * PAGE_SIZE;
+       if (max_length > max_ph_size
+               max_length = max_ph_size;
 
        if (max_length <= PAGE_SIZE)
                goto out;
 
-       min_ph_size_in_bytes = min_ph_size * PAGE_SIZE;
-
        if (object->internal)
                object_size = object->vo_size;
        else
@@ -7260,11 +7595,11 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                        *io_streaming = 1;
                } else {
 
-                       if (object->pages_created < (20 * min_ph_size)) {
+                       if (object->pages_created < (20 * (min_ph_size >> PAGE_SHIFT))) {
                                /*
                                 * prime the pump
                                 */
-                               pre_heat_size = min_ph_size_in_bytes;
+                               pre_heat_size = min_ph_size;
                        } else {
                                /*
                                 * Linear growth in PH size: The maximum size is max_length...
@@ -7272,10 +7607,10 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                                 * power of 2 nor a multiple of PAGE_SIZE... so round
                                 * it up to the nearest PAGE_SIZE boundary
                                 */
-                               pre_heat_size = (max_length * object->pages_used) / object->pages_created;
-                               
-                               if (pre_heat_size < min_ph_size_in_bytes)
-                                       pre_heat_size = min_ph_size_in_bytes;
+                               pre_heat_size = (max_length * (uint64_t)object->pages_used) / object->pages_created;
+
+                               if (pre_heat_size < min_ph_size)
+                                       pre_heat_size = min_ph_size;
                                else
                                        pre_heat_size = round_page(pre_heat_size);
                        }
@@ -7314,7 +7649,7 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
        if (pre_heat_size > max_length)
                pre_heat_size = max_length;
 
-       if (behavior == VM_BEHAVIOR_DEFAULT && (pre_heat_size > min_ph_size_in_bytes)) {
+       if (behavior == VM_BEHAVIOR_DEFAULT && (pre_heat_size > min_ph_size)) {
 
                unsigned int consider_free = vm_page_free_count + vm_page_cleaned_count;
                
@@ -7324,8 +7659,8 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                        pre_heat_size = trunc_page(pre_heat_size / 4);
                }
                
-               if (pre_heat_size < min_ph_size_in_bytes)
-                       pre_heat_size = min_ph_size_in_bytes;
+               if (pre_heat_size < min_ph_size)
+                       pre_heat_size = min_ph_size;
        }
        if (look_ahead == TRUE) {
                if (look_behind == TRUE) { 
@@ -7373,9 +7708,7 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                tail_size = 0;
        }
        assert( !(target_start & PAGE_MASK_64));
-       assert( !(pre_heat_size & PAGE_MASK));
-
-       pre_heat_scaling[pre_heat_size / PAGE_SIZE]++;
+       assert( !(pre_heat_size & PAGE_MASK_64));
 
        if (pre_heat_size <= PAGE_SIZE)
                goto out;
@@ -7395,21 +7728,11 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                         */
                        if (offset < fault_info->lo_offset)
                                break;
-                       /*
-                        * for external objects and internal objects w/o an existence map
-                        * vm_externl_state_get will return VM_EXTERNAL_STATE_UNKNOWN
+                       /*
+                        * for external objects or internal objects w/o a pager,
+                        * VM_COMPRESSOR_PAGER_STATE_GET will return VM_EXTERNAL_STATE_UNKNOWN
                         */
-#if MACH_PAGEMAP
-                       if (vm_external_state_get(object->existence_map, offset) == VM_EXTERNAL_STATE_ABSENT) {
-                               /*
-                                * we know for a fact that the pager can't provide the page
-                                * so don't include it or any pages beyond it in this cluster
-                                */
-                               break;
-                       }
-#endif /* MACH_PAGEMAP */
-                       if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset)
-                           == VM_EXTERNAL_STATE_ABSENT) {
+                       if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset) == VM_EXTERNAL_STATE_ABSENT) {
                                break;
                        }
                        if (vm_page_lookup(object, offset) != VM_PAGE_NULL) {
@@ -7431,21 +7754,11 @@ vm_object_cluster_size(vm_object_t object, vm_object_offset_t *start,
                                break;
                        assert(offset < object_size);
 
-                       /*
-                        * for external objects and internal objects w/o an existence map
-                        * vm_externl_state_get will return VM_EXTERNAL_STATE_UNKNOWN
+                       /*
+                        * for external objects or internal objects w/o a pager,
+                        * VM_COMPRESSOR_PAGER_STATE_GET will return VM_EXTERNAL_STATE_UNKNOWN
                         */
-#if MACH_PAGEMAP
-                       if (vm_external_state_get(object->existence_map, offset) == VM_EXTERNAL_STATE_ABSENT) {
-                               /*
-                                * we know for a fact that the pager can't provide the page
-                                * so don't include it or any pages beyond it in this cluster
-                                */
-                               break;
-                       }
-#endif /* MACH_PAGEMAP */
-                       if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset)
-                           == VM_EXTERNAL_STATE_ABSENT) {
+                       if (VM_COMPRESSOR_PAGER_STATE_GET(object, offset) == VM_EXTERNAL_STATE_ABSENT) {
                                break;
                        }
                        if (vm_page_lookup(object, offset) != VM_PAGE_NULL) {
@@ -7461,8 +7774,6 @@ out:
        if (*length > max_length)
                *length = max_length;
 
-       pre_heat_cluster[*length / PAGE_SIZE]++;
-
        vm_object_unlock(object);
        
        DTRACE_VM1(clustersize, vm_size_t, *length);
@@ -7522,7 +7833,7 @@ vm_object_page_op(
 
                if (ops & UPL_POP_DUMP) {
                        if (dst_page->pmapped == TRUE)
-                               pmap_disconnect(dst_page->phys_page);
+                               pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(dst_page));
 
                        VM_PAGE_FREE(dst_page);
                        break;
@@ -7535,7 +7846,7 @@ vm_object_page_op(
                        /* are undertaken */
 
                        if(dst_page->dirty) *flags |= UPL_POP_DIRTY;
-                       if(dst_page->pageout) *flags |= UPL_POP_PAGEOUT;
+                       if(dst_page->free_when_done) *flags |= UPL_POP_PAGEOUT;
                        if(dst_page->precious) *flags |= UPL_POP_PRECIOUS;
                        if(dst_page->absent) *flags |= UPL_POP_ABSENT;
                        if(dst_page->busy) *flags |= UPL_POP_BUSY;
@@ -7555,7 +7866,7 @@ vm_object_page_op(
                        if (ops & UPL_POP_DIRTY) {
                                SET_PAGE_DIRTY(dst_page, FALSE);
                        }
-                       if (ops & UPL_POP_PAGEOUT) dst_page->pageout = TRUE;
+                       if (ops & UPL_POP_PAGEOUT) dst_page->free_when_done = TRUE;
                        if (ops & UPL_POP_PRECIOUS) dst_page->precious = TRUE;
                        if (ops & UPL_POP_ABSENT) dst_page->absent = TRUE;
                        if (ops & UPL_POP_BUSY) dst_page->busy = TRUE;
@@ -7564,7 +7875,7 @@ vm_object_page_op(
                if(ops & UPL_POP_CLR) {
                        assert(dst_page->busy);
                        if (ops & UPL_POP_DIRTY) dst_page->dirty = FALSE;
-                       if (ops & UPL_POP_PAGEOUT) dst_page->pageout = FALSE;
+                       if (ops & UPL_POP_PAGEOUT) dst_page->free_when_done = FALSE;
                        if (ops & UPL_POP_PRECIOUS) dst_page->precious = FALSE;
                        if (ops & UPL_POP_ABSENT) dst_page->absent = FALSE;
                        if (ops & UPL_POP_BUSY) {
@@ -7613,7 +7924,7 @@ vm_object_page_op(
                         */
                        assert(dst_page->busy);
                        assert(!dst_page->encrypted);
-                       *phys_entry = dst_page->phys_page;
+                       *phys_entry = VM_PAGE_GET_PHYS_PAGE(dst_page);
                }
 
                break;
@@ -7687,18 +7998,18 @@ vm_object_range_op(
                                         */
                                        continue;
                                }
-                               if (dst_page->laundry) {
-                                       dst_page->pageout = FALSE;
-                                       
+                               if (dst_page->laundry)
                                        vm_pageout_steal_laundry(dst_page, FALSE);
-                               }
+
                                if (dst_page->pmapped == TRUE)
-                                       pmap_disconnect(dst_page->phys_page);
+                                       pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(dst_page));
 
                                VM_PAGE_FREE(dst_page);
 
-                       } else if ((ops & UPL_ROP_ABSENT) && !dst_page->absent)
-                               break;
+                       } else if ((ops & UPL_ROP_ABSENT)
+                                          && (!dst_page->absent || dst_page->busy)) {
+                               break;
+                       }
                } else if (ops & UPL_ROP_PRESENT)
                        break;
 
@@ -7750,11 +8061,20 @@ kern_return_t pager_map_to_phys_contiguous(
        }
 
        clobbered_private = pager_object->private;
-       pager_object->private = TRUE;
+       if (pager_object->private != TRUE) {
+               vm_object_lock(pager_object);
+               pager_object->private = TRUE;
+               vm_object_unlock(pager_object);
+       }
        retval = vm_object_populate_with_private(pager_object, offset, page_num, size);
 
-       if (retval != KERN_SUCCESS)
-               pager_object->private = clobbered_private;
+       if (retval != KERN_SUCCESS) {
+               if (pager_object->private != clobbered_private) {
+                       vm_object_lock(pager_object);
+                       pager_object->private = clobbered_private;
+                       vm_object_unlock(pager_object);
+               }
+       }
 
 out:
        return retval;
@@ -7770,6 +8090,9 @@ vm_object_lock(vm_object_t object)
                mutex_pause(2);
        }
         lck_rw_lock_exclusive(&object->Lock);
+#if DEVELOPMENT || DEBUG
+       object->Lock_owner = current_thread();
+#endif
 }
 
 boolean_t
@@ -7785,7 +8108,14 @@ vm_object_lock_avoid(vm_object_t object)
 boolean_t
 _vm_object_lock_try(vm_object_t object)
 {
-       return (lck_rw_try_lock_exclusive(&object->Lock));
+       boolean_t       retval;
+
+       retval = lck_rw_try_lock_exclusive(&object->Lock);
+#if DEVELOPMENT || DEBUG
+       if (retval == TRUE)
+               object->Lock_owner = current_thread();
+#endif
+       return (retval);
 }
 
 boolean_t
@@ -7818,6 +8148,31 @@ vm_object_lock_try_shared(vm_object_t object)
        return (lck_rw_try_lock_shared(&object->Lock));
 }
 
+boolean_t
+vm_object_lock_upgrade(vm_object_t object)
+{      boolean_t       retval;
+
+       retval = lck_rw_lock_shared_to_exclusive(&object->Lock);
+#if DEVELOPMENT || DEBUG
+       if (retval == TRUE)
+               object->Lock_owner = current_thread();
+#endif
+       return (retval);
+}
+
+void
+vm_object_unlock(vm_object_t object)
+{
+#if DEVELOPMENT || DEBUG
+       if (object->Lock_owner) {
+               if (object->Lock_owner != current_thread())
+                       panic("vm_object_unlock: not owner - %p\n", object);
+               object->Lock_owner = 0;
+       }
+#endif
+       lck_rw_done(&object->Lock);
+}
+
 
 unsigned int vm_object_change_wimg_mode_count = 0;
 
@@ -7833,10 +8188,10 @@ vm_object_change_wimg_mode(vm_object_t object, unsigned int wimg_mode)
 
        vm_object_paging_wait(object, THREAD_UNINT);
 
-       queue_iterate(&object->memq, p, vm_page_t, listq) {
+       vm_page_queue_iterate(&object->memq, p, vm_page_t, listq) {
 
                if (!p->fictitious)
-                       pmap_set_cache_attributes(p->phys_page, wimg_mode);
+                       pmap_set_cache_attributes(VM_PAGE_GET_PHYS_PAGE(p), wimg_mode);
        }
        if (wimg_mode == VM_WIMG_USE_DEFAULT)
                object->set_cache_attr = FALSE;
@@ -7850,136 +8205,260 @@ vm_object_change_wimg_mode(vm_object_t object, unsigned int wimg_mode)
 
 #if CONFIG_FREEZE
 
-kern_return_t vm_object_pack(
-       unsigned int    *purgeable_count,
-       unsigned int    *wired_count,
-       unsigned int    *clean_count,
-       unsigned int    *dirty_count,
-       unsigned int    dirty_budget,
-       boolean_t       *shared,
-       vm_object_t     src_object,
-       struct default_freezer_handle *df_handle)
+/*
+ * This routine does the "relocation" of previously
+ * compressed pages belonging to this object that are
+ * residing in a number of compressed segments into
+ * a set of compressed segments dedicated to hold
+ * compressed pages belonging to this object.
+ */
+
+extern void *freezer_chead;
+extern char *freezer_compressor_scratch_buf;
+extern int c_freezer_compression_count;
+extern AbsoluteTime c_freezer_last_yield_ts;
+
+#define        MAX_FREE_BATCH  32
+#define FREEZER_DUTY_CYCLE_ON_MS       5
+#define FREEZER_DUTY_CYCLE_OFF_MS      5
+
+static int c_freezer_should_yield(void);
+
+
+static int
+c_freezer_should_yield()
 {
-       kern_return_t   kr = KERN_SUCCESS;
-       
-       vm_object_lock(src_object);
+       AbsoluteTime    cur_time;
+       uint64_t        nsecs;
 
-       *purgeable_count = *wired_count = *clean_count = *dirty_count = 0;
-       *shared = FALSE;
+       assert(c_freezer_last_yield_ts);
+       clock_get_uptime(&cur_time);
 
-       if (!src_object->alive || src_object->terminating){
-               kr = KERN_FAILURE;
-               goto done;
-       }
+       SUB_ABSOLUTETIME(&cur_time, &c_freezer_last_yield_ts);
+       absolutetime_to_nanoseconds(cur_time, &nsecs);
 
-       if (src_object->purgable == VM_PURGABLE_VOLATILE) {
-               *purgeable_count = src_object->resident_page_count;
-               
-               /* If the default freezer handle is null, we're just walking the pages to discover how many can be hibernated */
-               if (df_handle != NULL) {
-                       purgeable_q_t queue;
-                       /* object should be on a queue */
-                       assert(src_object->objq.next != NULL &&
-                              src_object->objq.prev != NULL);
-                       queue = vm_purgeable_object_remove(src_object);
-                       assert(queue);
-                       if (src_object->purgeable_when_ripe) {
-                               vm_page_lock_queues();
-                               vm_purgeable_token_delete_first(queue);
-                               vm_page_unlock_queues();
-                       }
-                       vm_object_purge(src_object);
-               }
-               goto done;
-       }
+       if (nsecs > 1000 * 1000 * FREEZER_DUTY_CYCLE_ON_MS)
+               return (1);
+       return (0);
+}
 
-       if (src_object->ref_count == 1) {
-               vm_object_pack_pages(wired_count, clean_count, dirty_count, dirty_budget, src_object, df_handle);
-       } else {
-               if (src_object->internal) {
-                       *shared = TRUE;
-               }
-       }
-done:
-       vm_object_unlock(src_object);
-       
-       return kr;
+
+void
+vm_object_compressed_freezer_done()
+{
+       vm_compressor_finished_filling(&freezer_chead);
 }
 
 
 void
-vm_object_pack_pages(
-       unsigned int            *wired_count,
-       unsigned int            *clean_count,
-       unsigned int            *dirty_count,
-       unsigned int            dirty_budget,
-       vm_object_t             src_object,
-       struct default_freezer_handle *df_handle)
+vm_object_compressed_freezer_pageout(
+       vm_object_t object)
 {
-       vm_page_t p, next;
+       vm_page_t                       p;
+       vm_page_t                       local_freeq = NULL;
+       int                             local_freed = 0;
+       kern_return_t                   retval = KERN_SUCCESS;
+       int                             obj_resident_page_count_snapshot = 0;
 
-       next = (vm_page_t)queue_first(&src_object->memq);
+       assert(object != VM_OBJECT_NULL);
+       assert(object->internal);
 
-       while (!queue_end(&src_object->memq, (queue_entry_t)next)) {
-               p = next;
-               next = (vm_page_t)queue_next(&next->listq);
-               
-               /* Finish up if we've hit our pageout limit */
-               if (dirty_budget && (dirty_budget == *dirty_count)) {
-                       break;
+       vm_object_lock(object);
+
+       if (!object->pager_initialized || object->pager == MEMORY_OBJECT_NULL)  {
+                       
+               if (!object->pager_initialized) {
+
+                       vm_object_collapse(object, (vm_object_offset_t) 0, TRUE);
+
+                       if (!object->pager_initialized)
+                               vm_object_compressor_pager_create(object);
                }
-               assert(!p->laundry);
 
-               if (p->fictitious || p->busy ) 
-                       continue;
-               
-               if (p->absent || p->unusual || p->error)
-                       continue;
-               
-               if (VM_PAGE_WIRED(p)) {
-                       (*wired_count)++;
-                       continue;
+               if (!object->pager_initialized || object->pager == MEMORY_OBJECT_NULL)  {
+                       vm_object_unlock(object);
+                       return;
                }
-               
-               if (df_handle == NULL) {
-                       if (p->dirty || pmap_is_modified(p->phys_page)) {
-                               (*dirty_count)++;
-                       } else {
-                               (*clean_count)++;                               
-                       }
-                       continue;
+       }
+                       
+       if (VM_CONFIG_FREEZER_SWAP_IS_ACTIVE) {
+               vm_object_offset_t      curr_offset = 0;
+
+               /*
+                * Go through the object and make sure that any
+                * previously compressed pages are relocated into
+                * a compressed segment associated with our "freezer_chead".
+                */
+               while (curr_offset < object->vo_size) {
+
+                       curr_offset = vm_compressor_pager_next_compressed(object->pager, curr_offset);
+       
+                       if (curr_offset == (vm_object_offset_t) -1)
+                               break;
+
+                       retval = vm_compressor_pager_relocate(object->pager, curr_offset, &freezer_chead);
+
+                       if (retval != KERN_SUCCESS)
+                               break;
+
+                       curr_offset += PAGE_SIZE_64;
                }
-               
-               if (p->cleaning) {
-                       p->pageout = TRUE;
+       }
+
+       /*
+        * We can't hold the object lock while heading down into the compressed pager
+        * layer because we might need the kernel map lock down there to allocate new
+        * compressor data structures. And if this same object is mapped in the kernel
+        * and there's a fault on it, then that thread will want the object lock while
+        * holding the kernel map lock.
+        *
+        * Since we are going to drop/grab the object lock repeatedly, we must make sure
+        * we won't be stuck in an infinite loop if the same page(s) keep getting
+        * decompressed. So we grab a snapshot of the number of pages in the object and
+        * we won't process any more than that number of pages.
+        */
+
+       obj_resident_page_count_snapshot = object->resident_page_count;
+
+       vm_object_activity_begin(object);
+
+       while ((obj_resident_page_count_snapshot--) && !vm_page_queue_empty(&object->memq)) {
+
+               p = (vm_page_t)vm_page_queue_first(&object->memq);
+
+               KERNEL_DEBUG(0xe0430004 | DBG_FUNC_START, object, local_freed, 0, 0, 0);
+
+               vm_page_lockspin_queues();
+
+               if (p->cleaning || p->fictitious || p->busy || p->absent || p->unusual || p->error || VM_PAGE_WIRED(p)) {
+
+                       vm_page_unlock_queues();
+
+                       KERNEL_DEBUG(0xe0430004 | DBG_FUNC_END, object, local_freed, 1, 0, 0);
+
+                       vm_page_queue_remove(&object->memq, p, vm_page_t, listq);
+                       vm_page_queue_enter(&object->memq, p, vm_page_t, listq);
+
                        continue;
                }
 
                if (p->pmapped == TRUE) {
-                       int refmod_state;
-                       refmod_state = pmap_disconnect(p->phys_page);
+                       int refmod_state, pmap_flags;
+
+                       if (p->dirty || p->precious) {
+                               pmap_flags = PMAP_OPTIONS_COMPRESSOR;
+                       } else {
+                               pmap_flags = PMAP_OPTIONS_COMPRESSOR_IFF_MODIFIED;
+                       }
+
+                       refmod_state = pmap_disconnect_options(VM_PAGE_GET_PHYS_PAGE(p), pmap_flags, NULL);
                        if (refmod_state & VM_MEM_MODIFIED) {
                                SET_PAGE_DIRTY(p, FALSE);
                        }
                }
                
-               if (p->dirty) {
-                       default_freezer_pack_page(p, df_handle);        
-                       (*dirty_count)++;
-               }
-               else {
+               if (p->dirty == FALSE && p->precious == FALSE) {
+                       /*
+                        * Clean and non-precious page.
+                        */
+                       vm_page_unlock_queues();
                        VM_PAGE_FREE(p);
-                       (*clean_count)++;
+
+                       KERNEL_DEBUG(0xe0430004 | DBG_FUNC_END, object, local_freed, 2, 0, 0);
+                       continue;
                }
+
+               if (p->laundry)
+                       vm_pageout_steal_laundry(p, TRUE);
+
+               vm_page_queues_remove(p, TRUE);
+
+               vm_page_unlock_queues();
+
+
+               /*
+                * In case the compressor fails to compress this page, we need it at
+                * the back of the object memq so that we don't keep trying to process it.
+                * Make the move here while we have the object lock held.
+                */
+
+               vm_page_queue_remove(&object->memq, p, vm_page_t, listq);
+               vm_page_queue_enter(&object->memq, p, vm_page_t, listq);
+
+               /*
+                * Grab an activity_in_progress here for vm_pageout_compress_page() to consume.
+                *
+                * Mark the page busy so no one messes with it while we have the object lock dropped.
+                */
+
+               p->busy = TRUE;
+
+               vm_object_activity_begin(object);
+
+               vm_object_unlock(object);
+
+               /*
+                * arg3 == FALSE  tells vm_pageout_compress_page that we don't hold the object lock and the pager may not be initialized.
+                */
+               if (vm_pageout_compress_page(&freezer_chead, freezer_compressor_scratch_buf, p, FALSE) == KERN_SUCCESS) {
+                       /*
+                        * page has already been un-tabled from the object via 'vm_page_remove'
+                        */
+                       p->snext = local_freeq;
+                       local_freeq = p;
+                       local_freed++;
+
+                       if (local_freed >= MAX_FREE_BATCH) {
+               
+                               vm_page_free_list(local_freeq, TRUE);
+                               
+                               local_freeq = NULL;
+                               local_freed = 0;
+                       }
+                       c_freezer_compression_count++;
+               }
+               KERNEL_DEBUG(0xe0430004 | DBG_FUNC_END, object, local_freed, 0, 0, 0);
+
+               if (local_freed == 0 && c_freezer_should_yield()) {
+
+                       thread_yield_internal(FREEZER_DUTY_CYCLE_OFF_MS);
+                       clock_get_uptime(&c_freezer_last_yield_ts);
+               }
+
+               vm_object_lock(object);
+       }
+
+       if (local_freeq) {
+               vm_page_free_list(local_freeq, TRUE);
+                               
+               local_freeq = NULL;
+               local_freed = 0;
+       }
+       
+       vm_object_activity_end(object);
+
+       vm_object_unlock(object);
+
+       if (c_freezer_should_yield()) {
+
+               thread_yield_internal(FREEZER_DUTY_CYCLE_OFF_MS);
+               clock_get_uptime(&c_freezer_last_yield_ts);
        }
 }
 
+#endif /* CONFIG_FREEZE */
+
+
 void
 vm_object_pageout(
        vm_object_t object)
 {
        vm_page_t                       p, next;
        struct  vm_pageout_queue        *iq;
+       boolean_t                       need_unlock = TRUE;
+
+       if (!VM_CONFIG_COMPRESSOR_IS_PRESENT)
+               return;
 
        iq = &vm_pageout_queue_internal;
        
@@ -7987,119 +8466,363 @@ vm_object_pageout(
        
        vm_object_lock(object);
 
-       if (DEFAULT_PAGER_IS_ACTIVE || DEFAULT_FREEZER_IS_ACTIVE) {
+       if (!object->internal ||
+           object->terminating ||
+           !object->alive) {
+               vm_object_unlock(object);
+               return;
+       }
+
+       if (!object->pager_initialized || object->pager == MEMORY_OBJECT_NULL)  {
+                       
                if (!object->pager_initialized) {
-                       /*
-                       *   If there is no memory object for the page, create
-                       *   one and hand it to the default pager.
-                       */
-                       vm_object_pager_create(object);
+
+                       vm_object_collapse(object, (vm_object_offset_t) 0, TRUE);
+
+                       if (!object->pager_initialized)
+                               vm_object_compressor_pager_create(object);
                }
-       }
 
+               if (!object->pager_initialized || object->pager == MEMORY_OBJECT_NULL)  {
+                       vm_object_unlock(object);
+                       return;
+               }
+       }
+                       
 ReScan:        
-       next = (vm_page_t)queue_first(&object->memq);
+       next = (vm_page_t)vm_page_queue_first(&object->memq);
 
-       while (!queue_end(&object->memq, (queue_entry_t)next)) {
+       while (!vm_page_queue_end(&object->memq, (vm_page_queue_entry_t)next)) {
                p = next;
-               next = (vm_page_t)queue_next(&next->listq);
+               next = (vm_page_t)vm_page_queue_next(&next->listq);
                
+               assert(p->vm_page_q_state != VM_PAGE_ON_FREE_Q);
+               
+               if ((p->vm_page_q_state == VM_PAGE_ON_THROTTLED_Q) ||
+                   p->encrypted_cleaning ||
+                   p->cleaning ||
+                   p->laundry ||
+                   p->busy ||
+                   p->absent ||
+                   p->error ||
+                   p->fictitious ||
+                   VM_PAGE_WIRED(p)) {
+                       /*
+                        * Page is already being cleaned or can't be cleaned.
+                        */
+                       continue;
+               }
+
                /* Throw to the pageout queue */
-               vm_page_lockspin_queues();
 
-               /*
-                * see if page is already in the process of
-                * being cleaned... if so, leave it alone
-                */
-               if (!p->laundry) {
+               vm_page_lockspin_queues();
+               need_unlock = TRUE;
 
-                       if (COMPRESSED_PAGER_IS_ACTIVE || DEFAULT_FREEZER_COMPRESSED_PAGER_IS_ACTIVE) {
+               if (vm_compressor_low_on_space()) {
+                       vm_page_unlock_queues();
+                       break;          
+               }
 
-                               if (VM_PAGE_Q_THROTTLED(iq)) {
+               if (VM_PAGE_Q_THROTTLED(iq)) {
                                        
-                                       iq->pgo_draining = TRUE;
+                       iq->pgo_draining = TRUE;
                                        
-                                       assert_wait((event_t) (&iq->pgo_laundry + 1), THREAD_INTERRUPTIBLE);
-                                       vm_page_unlock_queues();
-                                       vm_object_unlock(object);
+                       assert_wait((event_t) (&iq->pgo_laundry + 1),
+                                   THREAD_INTERRUPTIBLE);
+                       vm_page_unlock_queues();
+                       vm_object_unlock(object);
                                        
-                                       thread_block(THREAD_CONTINUE_NULL);
+                       thread_block(THREAD_CONTINUE_NULL);
 
-                                       vm_object_lock(object);
-                                       goto ReScan;
-                               }
+                       vm_object_lock(object);
+                       goto ReScan;
+               }
 
-                               if (p->fictitious || p->busy ) {
-                                       vm_page_unlock_queues();
-                                       continue;
-                               }
-                               
-                               if (p->absent || p->unusual || p->error || VM_PAGE_WIRED(p)) {
-                                       vm_page_unlock_queues();
-                                       continue;
-                               }
-                               
-                               if (p->cleaning) {
-                                       p->pageout = TRUE;
-                                       vm_page_unlock_queues();
-                                       continue;
-                               }
+               assert(!p->fictitious);
+               assert(!p->busy);
+               assert(!p->absent);
+               assert(!p->unusual);
+               assert(!p->error);
+               assert(!VM_PAGE_WIRED(p));
+               assert(!p->cleaning);
 
-                               if (p->pmapped == TRUE) {
-                                       int refmod_state;
-                                       refmod_state = pmap_disconnect_options(p->phys_page, PMAP_OPTIONS_COMPRESSOR, NULL);
-                                       if (refmod_state & VM_MEM_MODIFIED) {
-                                               SET_PAGE_DIRTY(p, FALSE);
-                                       }
-                               }
-                               
-                               if (p->dirty == FALSE) {
-                                       vm_page_unlock_queues();
-                                       VM_PAGE_FREE(p);
-                                       continue;
-                               }
+               if (p->pmapped == TRUE) {
+                       int refmod_state;
+                       int pmap_options;
+
+                       /*
+                        * Tell pmap the page should be accounted
+                        * for as "compressed" if it's been modified.
+                        */
+                       pmap_options =
+                               PMAP_OPTIONS_COMPRESSOR_IFF_MODIFIED;
+                       if (p->dirty || p->precious) {
+                               /*
+                                * We already know it's been modified,
+                                * so tell pmap to account for it
+                                * as "compressed".
+                                */
+                               pmap_options = PMAP_OPTIONS_COMPRESSOR;
                        }
+                       refmod_state = pmap_disconnect_options(VM_PAGE_GET_PHYS_PAGE(p),
+                                                              pmap_options,
+                                                              NULL);
+                       if (refmod_state & VM_MEM_MODIFIED) {
+                               SET_PAGE_DIRTY(p, FALSE);
+                       }
+               }
 
-                       VM_PAGE_QUEUES_REMOVE(p);
-                       vm_pageout_cluster(p, TRUE);
+               if (!p->dirty && !p->precious) {
+                       vm_page_unlock_queues();
+                       VM_PAGE_FREE(p);
+                       continue;
                }
-               vm_page_unlock_queues();
+
+               vm_page_queues_remove(p, TRUE);
+
+               if (vm_pageout_cluster(p, FALSE, TRUE))
+                       need_unlock = FALSE;
+
+               if (need_unlock == TRUE)
+                       vm_page_unlock_queues();
        }
 
        vm_object_unlock(object);
 }
 
-kern_return_t
-vm_object_pagein(
-       vm_object_t object)
+
+#if CONFIG_IOSCHED
+void
+vm_page_request_reprioritize(vm_object_t o, uint64_t blkno, uint32_t len, int prio)
 {
-       memory_object_t pager;
-       kern_return_t   kr;
+       io_reprioritize_req_t   req;
+       struct vnode            *devvp = NULL;  
 
-       vm_object_lock(object);
+       if(vnode_pager_get_object_devvp(o->pager, (uintptr_t *)&devvp) != KERN_SUCCESS)
+               return;
+       
+       /*
+        * Create the request for I/O reprioritization.
+        * We use the noblock variant of zalloc because we're holding the object
+        * lock here and we could cause a deadlock in low memory conditions.
+        */
+       req = (io_reprioritize_req_t)zalloc_noblock(io_reprioritize_req_zone);
+       if (req == NULL)
+               return;
+       req->blkno = blkno;
+       req->len = len;
+       req->priority = prio;
+       req->devvp = devvp;
 
-       pager = object->pager;
+       /* Insert request into the reprioritization list */
+       IO_REPRIORITIZE_LIST_LOCK();
+       queue_enter(&io_reprioritize_list, req, io_reprioritize_req_t, io_reprioritize_list);
+       IO_REPRIORITIZE_LIST_UNLOCK();
 
-       if (!object->pager_ready || pager == MEMORY_OBJECT_NULL) {
-               vm_object_unlock(object);
-               return KERN_FAILURE;
+       /* Wakeup reprioritize thread */
+       IO_REPRIO_THREAD_WAKEUP();      
+
+       return;         
+}      
+
+void
+vm_decmp_upl_reprioritize(upl_t upl, int prio)
+{
+       int offset;
+       vm_object_t object;
+       io_reprioritize_req_t   req;
+       struct vnode            *devvp = NULL;
+       uint64_t                blkno;
+       uint32_t                len;
+       upl_t                   io_upl;
+       uint64_t                *io_upl_reprio_info;
+       int                     io_upl_size;
+
+       if ((upl->flags & UPL_TRACKED_BY_OBJECT) == 0 || (upl->flags & UPL_EXPEDITE_SUPPORTED) == 0)
+               return;
+
+       /* 
+        * We dont want to perform any allocations with the upl lock held since that might 
+        * result in a deadlock. If the system is low on memory, the pageout thread would 
+        * try to pageout stuff and might wait on this lock. If we are waiting for the memory to
+        * be freed up by the pageout thread, it would be a deadlock.
+        */
+
+
+       /* First step is just to get the size of the upl to find out how big the reprio info is */
+       if(!upl_try_lock(upl))
+               return;
+
+       if (upl->decmp_io_upl == NULL) {
+               /* The real I/O upl was destroyed by the time we came in here. Nothing to do. */
+               upl_unlock(upl);
+               return;
        }
+
+       io_upl = upl->decmp_io_upl;
+       assert((io_upl->flags & UPL_DECMP_REAL_IO) != 0);
+       io_upl_size = io_upl->size;
+       upl_unlock(upl);
        
-       vm_object_paging_wait(object, THREAD_UNINT);
-       vm_object_paging_begin(object);
+       /* Now perform the allocation */
+       io_upl_reprio_info = (uint64_t *)kalloc(sizeof(uint64_t) * (io_upl_size / PAGE_SIZE));
+       if (io_upl_reprio_info == NULL)
+               return;
 
-       object->blocked_access = TRUE;
-       vm_object_unlock(object);
+       /* Now again take the lock, recheck the state and grab out the required info */
+       if(!upl_try_lock(upl))
+               goto out;
+
+       if (upl->decmp_io_upl == NULL || upl->decmp_io_upl != io_upl) {
+               /* The real I/O upl was destroyed by the time we came in here. Nothing to do. */
+               upl_unlock(upl);
+               goto out;
+       }
+       memcpy(io_upl_reprio_info, io_upl->upl_reprio_info, sizeof(uint64_t) * (io_upl_size / PAGE_SIZE));
+
+       /* Get the VM object for this UPL */
+       if (io_upl->flags & UPL_SHADOWED) {
+               object = io_upl->map_object->shadow;
+       } else {
+               object = io_upl->map_object;
+       }
+
+       /* Get the dev vnode ptr for this object */
+       if(!object || !object->pager || 
+          vnode_pager_get_object_devvp(object->pager, (uintptr_t *)&devvp) != KERN_SUCCESS) {
+               upl_unlock(upl);
+               goto out;
+       }
+
+       upl_unlock(upl);
+
+       /* Now we have all the information needed to do the expedite */
+
+       offset = 0;
+       while (offset < io_upl_size) {
+               blkno   = io_upl_reprio_info[(offset / PAGE_SIZE)] & UPL_REPRIO_INFO_MASK;
+               len     = (io_upl_reprio_info[(offset / PAGE_SIZE)] >> UPL_REPRIO_INFO_SHIFT) & UPL_REPRIO_INFO_MASK;   
+
+               /*
+                * This implementation may cause some spurious expedites due to the 
+                * fact that we dont cleanup the blkno & len from the upl_reprio_info 
+                * even after the I/O is complete. 
+                */
+               
+               if (blkno != 0 && len != 0) {
+                       /* Create the request for I/O reprioritization */
+                               req = (io_reprioritize_req_t)zalloc(io_reprioritize_req_zone);
+                       assert(req != NULL);
+                       req->blkno = blkno;
+                       req->len = len;
+                       req->priority = prio;
+                       req->devvp = devvp;
+
+                       /* Insert request into the reprioritization list */
+                       IO_REPRIORITIZE_LIST_LOCK();
+                       queue_enter(&io_reprioritize_list, req, io_reprioritize_req_t, io_reprioritize_list);
+                       IO_REPRIORITIZE_LIST_UNLOCK();          
+                       
+                       offset += len;
+               } else {
+                       offset += PAGE_SIZE;
+               }
+       }
+
+       /* Wakeup reprioritize thread */
+        IO_REPRIO_THREAD_WAKEUP();
+
+out:
+       kfree(io_upl_reprio_info, sizeof(uint64_t) * (io_upl_size / PAGE_SIZE));
+       return;
+}
+
+void
+vm_page_handle_prio_inversion(vm_object_t o, vm_page_t m)
+{
+       upl_t upl;
+        upl_page_info_t *pl;
+        unsigned int i, num_pages;
+        int cur_tier;
+
+       cur_tier = proc_get_effective_thread_policy(current_thread(), TASK_POLICY_IO);
+
+       /* 
+       Scan through all UPLs associated with the object to find the 
+       UPL containing the contended page.
+       */ 
+       queue_iterate(&o->uplq, upl, upl_t, uplq) {
+               if (((upl->flags & UPL_EXPEDITE_SUPPORTED) == 0) || upl->upl_priority <= cur_tier)
+                       continue;
+               pl = UPL_GET_INTERNAL_PAGE_LIST(upl);
+                num_pages = (upl->size / PAGE_SIZE);
+                
+               /*
+               For each page in the UPL page list, see if it matches the contended
+               page and was issued as a low prio I/O. 
+               */
+               for(i=0; i < num_pages; i++) {
+                       if(UPL_PAGE_PRESENT(pl,i) && VM_PAGE_GET_PHYS_PAGE(m) == pl[i].phys_addr) {
+                               if ((upl->flags & UPL_DECMP_REQ) && upl->decmp_io_upl) {
+                                       KERNEL_DEBUG_CONSTANT((MACHDBG_CODE(DBG_MACH_VM, VM_PAGE_EXPEDITE)) | DBG_FUNC_NONE, VM_KERNEL_UNSLIDE_OR_PERM(upl->upl_creator), VM_KERNEL_UNSLIDE_OR_PERM(m),
+                                               VM_KERNEL_UNSLIDE_OR_PERM(upl), upl->upl_priority, 0);
+                                       vm_decmp_upl_reprioritize(upl, cur_tier);
+                                       break;
+                               }
+                               KERNEL_DEBUG_CONSTANT((MACHDBG_CODE(DBG_MACH_VM, VM_PAGE_EXPEDITE)) | DBG_FUNC_NONE, VM_KERNEL_UNSLIDE_OR_PERM(upl->upl_creator), VM_KERNEL_UNSLIDE_OR_PERM(m),
+                                       upl->upl_reprio_info[i], upl->upl_priority, 0);
+                               if (UPL_REPRIO_INFO_BLKNO(upl, i) != 0 && UPL_REPRIO_INFO_LEN(upl, i) != 0) 
+                                       vm_page_request_reprioritize(o, UPL_REPRIO_INFO_BLKNO(upl, i), UPL_REPRIO_INFO_LEN(upl, i), cur_tier);
+                                break;
+                         }
+                }
+                /* Check if we found any hits */
+                 if (i != num_pages)
+                       break;
+       }
        
-       kr = memory_object_data_reclaim(pager, TRUE);
+       return;
+}      
 
-       vm_object_lock(object);
+wait_result_t
+vm_page_sleep(vm_object_t o, vm_page_t m, int interruptible)
+{
+       wait_result_t ret;
 
-       object->blocked_access = FALSE;
-       vm_object_paging_end(object);
+       KERNEL_DEBUG((MACHDBG_CODE(DBG_MACH_VM, VM_PAGE_SLEEP)) | DBG_FUNC_START, o, m, 0, 0, 0);
+       
+       if (o->io_tracking && ((m->busy == TRUE) || (m->cleaning == TRUE) || VM_PAGE_WIRED(m))) {
+               /* 
+               Indicates page is busy due to an I/O. Issue a reprioritize request if necessary.
+               */
+               vm_page_handle_prio_inversion(o,m);
+       }
+       m->wanted = TRUE;
+       ret = thread_sleep_vm_object(o, m, interruptible);
+       KERNEL_DEBUG((MACHDBG_CODE(DBG_MACH_VM, VM_PAGE_SLEEP)) | DBG_FUNC_END, o, m, 0, 0, 0);
+       return ret;
+}
 
-       vm_object_unlock(object);
+static void
+io_reprioritize_thread(void *param __unused, wait_result_t wr __unused)
+{
+       io_reprioritize_req_t   req = NULL;
        
-       return kr;
+       while(1) {
+
+               IO_REPRIORITIZE_LIST_LOCK();
+               if (queue_empty(&io_reprioritize_list)) {
+                       IO_REPRIORITIZE_LIST_UNLOCK();
+                       break;
+               }
+                       
+               queue_remove_first(&io_reprioritize_list, req, io_reprioritize_req_t, io_reprioritize_list);   
+               IO_REPRIORITIZE_LIST_UNLOCK();
+               
+               vnode_pager_issue_reprioritize_io(req->devvp, req->blkno, req->len, req->priority);
+               zfree(io_reprioritize_req_zone, req);   
+       }       
+       
+       IO_REPRIO_THREAD_CONTINUATION();
 }
-#endif /* CONFIG_FREEZE */
+#endif