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diff --git a/kern/task.c b/kern/task.c
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+/* 
+ * Mach Operating System
+ * Copyright (c) 1993-1988 Carnegie Mellon University
+ * All Rights Reserved.
+ * 
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ * 
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ * 
+ * Carnegie Mellon requests users of this software to return to
+ * 
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ * 
+ * any improvements or extensions that they make and grant Carnegie Mellon
+ * the rights to redistribute these changes.
+ */
+/*
+ *	File:	kern/task.c
+ *	Author:	Avadis Tevanian, Jr., Michael Wayne Young, David Golub,
+ *		David Black
+ *
+ *	Task management primitives implementation.
+ */
+
+#include <mach_host.h>
+#include <mach_pcsample.h>
+#include <norma_task.h>
+#include <fast_tas.h>
+#include <net_atm.h>
+
+#include <mach/machine/vm_types.h>
+#include <mach/vm_param.h>
+#include <mach/task_info.h>
+#include <mach/task_special_ports.h>
+#include <ipc/ipc_space.h>
+#include <ipc/ipc_types.h>
+#include <kern/mach_param.h>
+#include <kern/task.h>
+#include <kern/thread.h>
+#include <kern/zalloc.h>
+#include <kern/kalloc.h>
+#include <kern/processor.h>
+#include <kern/sched_prim.h>	/* for thread_wakeup */
+#include <kern/ipc_tt.h>
+#include <vm/vm_kern.h>		/* for kernel_map, ipc_kernel_map */
+#include <machine/machspl.h>	/* for splsched */
+
+#if	NET_ATM
+#include <chips/nw_mk.h>
+#endif
+
+#if	NORMA_TASK
+#define	task_create	task_create_local
+#endif	/* NORMA_TASK */
+
+task_t	kernel_task = TASK_NULL;
+zone_t	task_zone;
+
+extern void eml_init(void);
+extern void eml_task_reference(task_t, task_t);
+extern void eml_task_deallocate(task_t);
+
+void task_init(void)
+{
+	task_zone = zinit(
+			sizeof(struct task),
+			TASK_MAX * sizeof(struct task),
+			TASK_CHUNK * sizeof(struct task),
+			0, "tasks");
+
+	eml_init();
+
+	/*
+	 * Create the kernel task as the first task.
+	 * Task_create must assign to kernel_task as a side effect,
+	 * for other initialization. (:-()
+	 */
+	(void) task_create(TASK_NULL, FALSE, &kernel_task);
+}
+
+/*
+ * Create a task running in the kernel address space.  It may
+ * have its own map of size mem_size (if 0, it uses the kernel map),
+ * and may have ipc privileges.
+ */
+task_t	kernel_task_create(
+	task_t		parent_task,
+	vm_size_t	map_size)
+{
+	task_t		new_task;
+	vm_offset_t	min, max;
+
+	/*
+	 * Create the task.
+	 */
+	(void) task_create(parent_task, FALSE, &new_task);
+
+	/*
+	 * Task_create creates the task with a user-space map.
+	 * Remove the map and replace it with the kernel map
+	 * or a submap of the kernel map.
+	 */
+	vm_map_deallocate(new_task->map);
+	if (map_size == 0)
+	    new_task->map = kernel_map;
+	else
+	    new_task->map = kmem_suballoc(kernel_map, &min, &max,
+					  map_size, FALSE);
+
+	return new_task;
+}
+
+kern_return_t task_create(
+	task_t		parent_task,
+	boolean_t	inherit_memory,
+	task_t		*child_task)		/* OUT */
+{
+	register task_t	new_task;
+	register processor_set_t	pset;
+	int i;
+
+	new_task = (task_t) zalloc(task_zone);
+	if (new_task == TASK_NULL) {
+		panic("task_create: no memory for task structure");
+	}
+
+	/* one ref for just being alive; one for our caller */
+	new_task->ref_count = 2;
+
+	if (child_task == &kernel_task)  {
+		new_task->map = kernel_map; 
+	} else if (inherit_memory) {
+		new_task->map = vm_map_fork(parent_task->map);
+	} else {
+		new_task->map = vm_map_create(pmap_create(0),
+					round_page(VM_MIN_ADDRESS),
+					trunc_page(VM_MAX_ADDRESS), TRUE);
+	}
+
+	simple_lock_init(&new_task->lock);
+	queue_init(&new_task->thread_list);
+	new_task->suspend_count = 0;
+	new_task->active = TRUE;
+	new_task->user_stop_count = 0;
+	new_task->thread_count = 0;
+
+	eml_task_reference(new_task, parent_task);
+
+	ipc_task_init(new_task, parent_task);
+
+#if	NET_ATM
+	new_task->nw_ep_owned = 0;
+#endif
+
+	new_task->total_user_time.seconds = 0;
+	new_task->total_user_time.microseconds = 0;
+	new_task->total_system_time.seconds = 0;
+	new_task->total_system_time.microseconds = 0;
+
+	if (parent_task != TASK_NULL) {
+		task_lock(parent_task);
+		pset = parent_task->processor_set;
+		if (!pset->active)
+			pset = &default_pset;
+		pset_reference(pset);
+		new_task->priority = parent_task->priority;
+		task_unlock(parent_task);
+	}
+	else {
+		pset = &default_pset;
+		pset_reference(pset);
+		new_task->priority = BASEPRI_USER;
+	}
+	pset_lock(pset);
+	pset_add_task(pset, new_task);
+	pset_unlock(pset);
+
+	new_task->may_assign = TRUE;
+	new_task->assign_active = FALSE;
+
+#if	MACH_PCSAMPLE
+	new_task->pc_sample.buffer = 0;
+	new_task->pc_sample.seqno = 0;
+	new_task->pc_sample.sampletypes = 0;
+#endif	/* MACH_PCSAMPLE */
+
+#if	FAST_TAS
+	for (i = 0; i < TASK_FAST_TAS_NRAS; i++)  {
+	    if (inherit_memory) {
+		new_task->fast_tas_base[i] = parent_task->fast_tas_base[i];
+ 		new_task->fast_tas_end[i]  = parent_task->fast_tas_end[i];
+	    } else {
+ 		new_task->fast_tas_base[i] = (vm_offset_t)0;
+ 		new_task->fast_tas_end[i]  = (vm_offset_t)0;
+	    }
+	}
+#endif	/* FAST_TAS */
+ 
+	ipc_task_enable(new_task);
+
+#if	NORMA_TASK
+	new_task->child_node = -1;
+#endif	/* NORMA_TASK */
+
+	*child_task = new_task;
+	return KERN_SUCCESS;
+}
+
+/*
+ *	task_deallocate:
+ *
+ *	Give up a reference to the specified task and destroy it if there
+ *	are no other references left.  It is assumed that the current thread
+ *	is never in this task.
+ */
+void task_deallocate(
+	register task_t	task)
+{
+	register int c;
+	register processor_set_t pset;
+
+	if (task == TASK_NULL)
+		return;
+
+	task_lock(task);
+	c = --(task->ref_count);
+	task_unlock(task);
+	if (c != 0)
+		return;
+
+#if	NORMA_TASK
+	if (task->map == VM_MAP_NULL) {
+		/* norma placeholder task */
+		zfree(task_zone, (vm_offset_t) task);
+		return;
+	}
+#endif	/* NORMA_TASK */
+
+	eml_task_deallocate(task);
+
+	pset = task->processor_set;
+	pset_lock(pset);
+	pset_remove_task(pset,task);
+	pset_unlock(pset);
+	pset_deallocate(pset);
+	vm_map_deallocate(task->map);
+	is_release(task->itk_space);
+	zfree(task_zone, (vm_offset_t) task);
+}
+
+void task_reference(
+	register task_t	task)
+{
+	if (task == TASK_NULL)
+		return;
+
+	task_lock(task);
+	task->ref_count++;
+	task_unlock(task);
+}
+
+/*
+ *	task_terminate:
+ *
+ *	Terminate the specified task.  See comments on thread_terminate
+ *	(kern/thread.c) about problems with terminating the "current task."
+ */
+kern_return_t task_terminate(
+	register task_t	task)
+{
+	register thread_t	thread, cur_thread;
+	register queue_head_t	*list;
+	register task_t		cur_task;
+	spl_t			s;
+
+	if (task == TASK_NULL)
+		return KERN_INVALID_ARGUMENT;
+
+	list = &task->thread_list;
+	cur_task = current_task();
+	cur_thread = current_thread();
+
+#if	NET_ATM
+	/*
+	 *      Shut down networking.
+         */
+	mk_endpoint_collect(task);
+#endif
+
+	/*
+	 *	Deactivate task so that it can't be terminated again,
+	 *	and so lengthy operations in progress will abort.
+	 *
+	 *	If the current thread is in this task, remove it from
+	 *	the task's thread list to keep the thread-termination
+	 *	loop simple.
+	 */
+	if (task == cur_task) {
+		task_lock(task);
+		if (!task->active) {
+			/*
+			 *	Task is already being terminated.
+			 */
+			task_unlock(task);
+			return KERN_FAILURE;
+		}
+		/*
+		 *	Make sure current thread is not being terminated.
+		 */
+		s = splsched();
+		thread_lock(cur_thread);
+		if (!cur_thread->active) {
+			thread_unlock(cur_thread);
+			(void) splx(s);
+			task_unlock(task);
+			thread_terminate(cur_thread);
+			return KERN_FAILURE;
+		}
+		task->active = FALSE;
+		queue_remove(list, cur_thread, thread_t, thread_list);
+		thread_unlock(cur_thread);
+		(void) splx(s);
+		task_unlock(task);
+
+		/*
+		 *	Shut down this thread's ipc now because it must
+		 *	be left alone to terminate the task.
+		 */
+		ipc_thread_disable(cur_thread);
+		ipc_thread_terminate(cur_thread);
+	}
+	else {
+		/*
+		 *	Lock both current and victim task to check for
+		 *	potential deadlock.
+		 */
+		if ((vm_offset_t)task < (vm_offset_t)cur_task) {
+			task_lock(task);
+			task_lock(cur_task);
+		}
+		else {
+			task_lock(cur_task);
+			task_lock(task);
+		}
+		/*
+		 *	Check if current thread or task is being terminated.
+		 */
+		s = splsched();
+		thread_lock(cur_thread);
+		if ((!cur_task->active) ||(!cur_thread->active)) {
+			/*
+			 * Current task or thread is being terminated.
+			 */
+			thread_unlock(cur_thread);
+			(void) splx(s);
+			task_unlock(task);
+			task_unlock(cur_task);
+			thread_terminate(cur_thread);
+			return KERN_FAILURE;
+		}
+		thread_unlock(cur_thread);
+		(void) splx(s);
+		task_unlock(cur_task);
+
+		if (!task->active) {
+			/*
+			 *	Task is already being terminated.
+			 */
+			task_unlock(task);
+			return KERN_FAILURE;
+		}
+		task->active = FALSE;
+		task_unlock(task);
+	}
+
+	/*
+	 *	Prevent further execution of the task.  ipc_task_disable
+	 *	prevents further task operations via the task port.
+	 *	If this is the current task, the current thread will
+	 *	be left running.
+	 */
+	ipc_task_disable(task);
+	(void) task_hold(task);
+	(void) task_dowait(task,TRUE);			/* may block */
+
+	/*
+	 *	Terminate each thread in the task.
+	 *
+         *      The task_port is closed down, so no more thread_create
+         *      operations can be done.  Thread_force_terminate closes the
+         *      thread port for each thread; when that is done, the
+         *      thread will eventually disappear.  Thus the loop will
+         *      terminate.  Call thread_force_terminate instead of
+         *      thread_terminate to avoid deadlock checks.  Need
+         *      to call thread_block() inside loop because some other
+         *      thread (e.g., the reaper) may have to run to get rid
+         *      of all references to the thread; it won't vanish from
+         *      the task's thread list until the last one is gone.
+         */
+        task_lock(task);
+        while (!queue_empty(list)) {
+                thread = (thread_t) queue_first(list);
+                thread_reference(thread);
+                task_unlock(task);
+                thread_force_terminate(thread);
+                thread_deallocate(thread);
+                thread_block((void (*)()) 0);
+                task_lock(task);
+        }
+        task_unlock(task);
+
+	/*
+	 *	Shut down IPC.
+	 */
+	ipc_task_terminate(task);
+
+
+	/*
+	 *	Deallocate the task's reference to itself.
+	 */
+	task_deallocate(task);
+
+	/*
+	 *	If the current thread is in this task, it has not yet
+	 *	been terminated (since it was removed from the task's
+	 *	thread-list).  Put it back in the thread list (for
+	 *	completeness), and terminate it.  Since it holds the
+	 *	last reference to the task, terminating it will deallocate
+	 *	the task.
+	 */
+	if (cur_thread->task == task) {
+		task_lock(task);
+		s = splsched();
+		queue_enter(list, cur_thread, thread_t, thread_list);
+		(void) splx(s);
+		task_unlock(task);
+		(void) thread_terminate(cur_thread);
+	}
+
+	return KERN_SUCCESS;
+}
+
+/*
+ *	task_hold:
+ *
+ *	Suspend execution of the specified task.
+ *	This is a recursive-style suspension of the task, a count of
+ *	suspends is maintained.
+ */
+kern_return_t task_hold(
+	register task_t	task)
+{
+	register queue_head_t	*list;
+	register thread_t	thread, cur_thread;
+
+	cur_thread = current_thread();
+
+	task_lock(task);
+	if (!task->active) {
+		task_unlock(task);
+		return KERN_FAILURE;
+	}
+
+	task->suspend_count++;
+
+	/*
+	 *	Iterate through all the threads and hold them.
+	 *	Do not hold the current thread if it is within the
+	 *	task.
+	 */
+	list = &task->thread_list;
+	queue_iterate(list, thread, thread_t, thread_list) {
+		if (thread != cur_thread)
+			thread_hold(thread);
+	}
+	task_unlock(task);
+	return KERN_SUCCESS;
+}
+
+/*
+ *	task_dowait:
+ *
+ *	Wait until the task has really been suspended (all of the threads
+ *	are stopped).  Skip the current thread if it is within the task.
+ *
+ *	If task is deactivated while waiting, return a failure code unless
+ *	must_wait is true.
+ */
+kern_return_t task_dowait(
+	register task_t	task,
+	boolean_t must_wait)
+{
+	register queue_head_t	*list;
+	register thread_t	thread, cur_thread, prev_thread;
+	register kern_return_t	ret = KERN_SUCCESS;
+
+	/*
+	 *	Iterate through all the threads.
+	 *	While waiting for each thread, we gain a reference to it
+	 *	to prevent it from going away on us.  This guarantees
+	 *	that the "next" thread in the list will be a valid thread.
+	 *
+	 *	We depend on the fact that if threads are created while
+	 *	we are looping through the threads, they will be held
+	 *	automatically.  We don't care about threads that get
+	 *	deallocated along the way (the reference prevents it
+	 *	from happening to the thread we are working with).
+	 *
+	 *	If the current thread is in the affected task, it is skipped.
+	 *
+	 *	If the task is deactivated before we're done, and we don't
+	 *	have to wait for it (must_wait is FALSE), just bail out.
+	 */
+	cur_thread = current_thread();
+
+	list = &task->thread_list;
+	prev_thread = THREAD_NULL;
+	task_lock(task);
+	queue_iterate(list, thread, thread_t, thread_list) {
+		if (!(task->active) && !(must_wait)) {
+			ret = KERN_FAILURE;
+			break;
+		}
+		if (thread != cur_thread) {
+			thread_reference(thread);
+			task_unlock(task);
+			if (prev_thread != THREAD_NULL)
+				thread_deallocate(prev_thread);
+							/* may block */
+			(void) thread_dowait(thread, TRUE);  /* may block */
+			prev_thread = thread;
+			task_lock(task);
+		}
+	}
+	task_unlock(task);
+	if (prev_thread != THREAD_NULL)
+		thread_deallocate(prev_thread);		/* may block */
+	return ret;
+}
+
+kern_return_t task_release(
+	register task_t	task)
+{
+	register queue_head_t	*list;
+	register thread_t	thread, next;
+
+	task_lock(task);
+	if (!task->active) {
+		task_unlock(task);
+		return KERN_FAILURE;
+	}
+
+	task->suspend_count--;
+
+	/*
+	 *	Iterate through all the threads and release them
+	 */
+	list = &task->thread_list;
+	thread = (thread_t) queue_first(list);
+	while (!queue_end(list, (queue_entry_t) thread)) {
+		next = (thread_t) queue_next(&thread->thread_list);
+		thread_release(thread);
+		thread = next;
+	}
+	task_unlock(task);
+	return KERN_SUCCESS;
+}
+
+kern_return_t task_threads(
+	task_t		task,
+	thread_array_t	*thread_list,
+	natural_t	*count)
+{
+	unsigned int actual;	/* this many threads */
+	thread_t thread;
+	thread_t *threads;
+	int i;
+
+	vm_size_t size, size_needed;
+	vm_offset_t addr;
+
+	if (task == TASK_NULL)
+		return KERN_INVALID_ARGUMENT;
+
+	size = 0; addr = 0;
+
+	for (;;) {
+		task_lock(task);
+		if (!task->active) {
+			task_unlock(task);
+			return KERN_FAILURE;
+		}
+
+		actual = task->thread_count;
+
+		/* do we have the memory we need? */
+
+		size_needed = actual * sizeof(mach_port_t);
+		if (size_needed <= size)
+			break;
+
+		/* unlock the task and allocate more memory */
+		task_unlock(task);
+
+		if (size != 0)
+			kfree(addr, size);
+
+		assert(size_needed > 0);
+		size = size_needed;
+
+		addr = kalloc(size);
+		if (addr == 0)
+			return KERN_RESOURCE_SHORTAGE;
+	}
+
+	/* OK, have memory and the task is locked & active */
+
+	threads = (thread_t *) addr;
+
+	for (i = 0, thread = (thread_t) queue_first(&task->thread_list);
+	     i < actual;
+	     i++, thread = (thread_t) queue_next(&thread->thread_list)) {
+		/* take ref for convert_thread_to_port */
+		thread_reference(thread);
+		threads[i] = thread;
+	}
+	assert(queue_end(&task->thread_list, (queue_entry_t) thread));
+
+	/* can unlock task now that we've got the thread refs */
+	task_unlock(task);
+
+	if (actual == 0) {
+		/* no threads, so return null pointer and deallocate memory */
+
+		*thread_list = 0;
+		*count = 0;
+
+		if (size != 0)
+			kfree(addr, size);
+	} else {
+		/* if we allocated too much, must copy */
+
+		if (size_needed < size) {
+			vm_offset_t newaddr;
+
+			newaddr = kalloc(size_needed);
+			if (newaddr == 0) {
+				for (i = 0; i < actual; i++)
+					thread_deallocate(threads[i]);
+				kfree(addr, size);
+				return KERN_RESOURCE_SHORTAGE;
+			}
+
+			bcopy((char *) addr, (char *) newaddr, size_needed);
+			kfree(addr, size);
+			threads = (thread_t *) newaddr;
+		}
+
+		*thread_list = (mach_port_t *) threads;
+		*count = actual;
+
+		/* do the conversion that Mig should handle */
+
+		for (i = 0; i < actual; i++)
+			((ipc_port_t *) threads)[i] =
+				convert_thread_to_port(threads[i]);
+	}
+
+	return KERN_SUCCESS;
+}
+
+kern_return_t task_suspend(
+	register task_t	task)
+{
+	register boolean_t	hold;
+
+	if (task == TASK_NULL)
+		return KERN_INVALID_ARGUMENT;
+
+	hold = FALSE;
+	task_lock(task);
+	if ((task->user_stop_count)++ == 0)
+		hold = TRUE;
+	task_unlock(task);
+
+	/*
+	 *	If the stop count was positive, the task is
+	 *	already stopped and we can exit.
+	 */
+	if (!hold) {
+		return KERN_SUCCESS;
+	}
+
+	/*
+	 *	Hold all of the threads in the task, and wait for
+	 *	them to stop.  If the current thread is within
+	 *	this task, hold it separately so that all of the
+	 *	other threads can stop first.
+	 */
+
+	if (task_hold(task) != KERN_SUCCESS)
+		return KERN_FAILURE;
+
+	if (task_dowait(task, FALSE) != KERN_SUCCESS)
+		return KERN_FAILURE;
+
+	if (current_task() == task) {
+		spl_t s;
+
+		thread_hold(current_thread());
+		/*
+		 *	We want to call thread_block on our way out,
+		 *	to stop running.
+		 */
+		s = splsched();
+		ast_on(cpu_number(), AST_BLOCK);
+		(void) splx(s);
+	}
+
+	return KERN_SUCCESS;
+}
+
+kern_return_t task_resume(
+	register task_t	task)
+{
+	register boolean_t	release;
+
+	if (task == TASK_NULL)
+		return KERN_INVALID_ARGUMENT;
+
+	release = FALSE;
+	task_lock(task);
+	if (task->user_stop_count > 0) {
+		if (--(task->user_stop_count) == 0)
+	    		release = TRUE;
+	}
+	else {
+		task_unlock(task);
+		return KERN_FAILURE;
+	}
+	task_unlock(task);
+
+	/*
+	 *	Release the task if necessary.
+	 */
+	if (release)
+		return task_release(task);
+
+	return KERN_SUCCESS;
+}
+
+kern_return_t task_info(
+	task_t			task,
+	int			flavor,
+	task_info_t		task_info_out,	/* pointer to OUT array */
+	natural_t		*task_info_count)	/* IN/OUT */
+{
+	vm_map_t		map;
+
+	if (task == TASK_NULL)
+		return KERN_INVALID_ARGUMENT;
+
+	switch (flavor) {
+	    case TASK_BASIC_INFO:
+	    {
+		register task_basic_info_t	basic_info;
+
+		if (*task_info_count < TASK_BASIC_INFO_COUNT) {
+		    return KERN_INVALID_ARGUMENT;
+		}
+
+		basic_info = (task_basic_info_t) task_info_out;
+
+		map = (task == kernel_task) ? kernel_map : task->map;
+
+		basic_info->virtual_size  = map->size;
+		basic_info->resident_size = pmap_resident_count(map->pmap)
+						   * PAGE_SIZE;
+
+		task_lock(task);
+		basic_info->base_priority = task->priority;
+		basic_info->suspend_count = task->user_stop_count;
+		basic_info->user_time.seconds
+				= task->total_user_time.seconds;
+		basic_info->user_time.microseconds
+				= task->total_user_time.microseconds;
+		basic_info->system_time.seconds
+				= task->total_system_time.seconds;
+		basic_info->system_time.microseconds 
+				= task->total_system_time.microseconds;
+		task_unlock(task);
+
+		*task_info_count = TASK_BASIC_INFO_COUNT;
+		break;
+	    }
+
+	    case TASK_THREAD_TIMES_INFO:
+	    {
+		register task_thread_times_info_t times_info;
+		register thread_t	thread;
+
+		if (*task_info_count < TASK_THREAD_TIMES_INFO_COUNT) {
+		    return KERN_INVALID_ARGUMENT;
+		}
+
+		times_info = (task_thread_times_info_t) task_info_out;
+		times_info->user_time.seconds = 0;
+		times_info->user_time.microseconds = 0;
+		times_info->system_time.seconds = 0;
+		times_info->system_time.microseconds = 0;
+
+		task_lock(task);
+		queue_iterate(&task->thread_list, thread,
+			      thread_t, thread_list)
+		{
+		    time_value_t user_time, system_time;
+		    spl_t		 s;
+
+		    s = splsched();
+		    thread_lock(thread);
+
+		    thread_read_times(thread, &user_time, &system_time);
+
+		    thread_unlock(thread);
+		    splx(s);
+
+		    time_value_add(&times_info->user_time, &user_time);
+		    time_value_add(&times_info->system_time, &system_time);
+		}
+		task_unlock(task);
+
+		*task_info_count = TASK_THREAD_TIMES_INFO_COUNT;
+		break;
+	    }
+
+	    default:
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	return KERN_SUCCESS;
+}
+
+#if	MACH_HOST
+/*
+ *	task_assign:
+ *
+ *	Change the assigned processor set for the task
+ */
+kern_return_t
+task_assign(
+	task_t		task,
+	processor_set_t	new_pset,
+	boolean_t	assign_threads)
+{
+	kern_return_t		ret = KERN_SUCCESS;
+	register thread_t	thread, prev_thread;
+	register queue_head_t	*list;
+	register processor_set_t	pset;
+
+	if (task == TASK_NULL || new_pset == PROCESSOR_SET_NULL) {
+		return KERN_INVALID_ARGUMENT;
+	}
+
+	/*
+	 *	Freeze task`s assignment.  Prelude to assigning
+	 *	task.  Only one freeze may be held per task.
+	 */
+
+	task_lock(task);
+	while (task->may_assign == FALSE) {
+		task->assign_active = TRUE;
+		assert_wait((event_t)&task->assign_active, TRUE);
+		task_unlock(task);
+		thread_block((void (*)()) 0);
+		task_lock(task);
+	}
+
+	/*
+	 *	Avoid work if task already in this processor set.
+	 */
+	if (task->processor_set == new_pset)  {
+		/*
+		 *	No need for task->assign_active wakeup:
+		 *	task->may_assign is still TRUE.
+		 */
+		task_unlock(task);
+		return KERN_SUCCESS;
+	}
+
+	task->may_assign = FALSE;
+	task_unlock(task);
+
+	/*
+	 *	Safe to get the task`s pset: it cannot change while
+	 *	task is frozen.
+	 */
+	pset = task->processor_set;
+
+	/*
+	 *	Lock both psets now.  Use ordering to avoid deadlock.
+	 */
+    Restart:
+	if ((vm_offset_t) pset < (vm_offset_t) new_pset) {
+	    pset_lock(pset);
+	    pset_lock(new_pset);
+	}
+	else {
+	    pset_lock(new_pset);
+	    pset_lock(pset);
+	}
+
+	/*
+	 *	Check if new_pset is ok to assign to.  If not,
+	 *	reassign to default_pset.
+	 */
+	if (!new_pset->active) {
+	    pset_unlock(pset);
+	    pset_unlock(new_pset);
+	    new_pset = &default_pset;
+	    goto Restart;
+	}
+
+	pset_reference(new_pset);
+
+	/*
+	 *	Now grab the task lock and move the task.
+	 */
+
+	task_lock(task);
+	pset_remove_task(pset, task);
+	pset_add_task(new_pset, task);
+
+	pset_unlock(pset);
+	pset_unlock(new_pset);
+
+	if (assign_threads == FALSE) {
+		/*
+		 *	We leave existing threads at their
+		 *	old assignments.  Unfreeze task`s
+		 *	assignment.
+		 */
+		task->may_assign = TRUE;
+		if (task->assign_active) {
+			task->assign_active = FALSE;
+			thread_wakeup((event_t) &task->assign_active);
+		}
+		task_unlock(task);
+		pset_deallocate(pset);
+		return KERN_SUCCESS;
+	}
+
+	/*
+	 *	If current thread is in task, freeze its assignment.
+	 */
+	if (current_thread()->task == task) {
+		task_unlock(task);
+		thread_freeze(current_thread());
+		task_lock(task);
+	}
+
+	/*
+	 *	Iterate down the thread list reassigning all the threads.
+	 *	New threads pick up task's new processor set automatically.
+	 *	Do current thread last because new pset may be empty.
+	 */
+	list = &task->thread_list;
+	prev_thread = THREAD_NULL;
+	queue_iterate(list, thread, thread_t, thread_list) {
+		if (!(task->active)) {
+			ret = KERN_FAILURE;
+			break;
+		}
+		if (thread != current_thread()) {
+			thread_reference(thread);
+			task_unlock(task);
+			if (prev_thread != THREAD_NULL)
+			    thread_deallocate(prev_thread); /* may block */
+			thread_assign(thread,new_pset);	    /* may block */
+			prev_thread = thread;
+			task_lock(task);
+		}
+	}
+
+	/*
+	 *	Done, wakeup anyone waiting for us.
+	 */
+	task->may_assign = TRUE;
+	if (task->assign_active) {
+		task->assign_active = FALSE;
+		thread_wakeup((event_t)&task->assign_active);
+	}
+	task_unlock(task);
+	if (prev_thread != THREAD_NULL)
+		thread_deallocate(prev_thread);		/* may block */
+
+	/*
+	 *	Finish assignment of current thread.
+	 */
+	if (current_thread()->task == task)
+		thread_doassign(current_thread(), new_pset, TRUE);
+
+	pset_deallocate(pset);
+
+	return ret;
+}
+#else	/* MACH_HOST */
+/*
+ *	task_assign:
+ *
+ *	Change the assigned processor set for the task
+ */
+kern_return_t
+task_assign(
+	task_t		task,
+	processor_set_t	new_pset,
+	boolean_t	assign_threads)
+{
+	return KERN_FAILURE;
+}
+#endif	/* MACH_HOST */
+	
+
+/*
+ *	task_assign_default:
+ *
+ *	Version of task_assign to assign to default processor set.
+ */
+kern_return_t
+task_assign_default(
+	task_t		task,
+	boolean_t	assign_threads)
+{
+	return task_assign(task, &default_pset, assign_threads);
+}
+
+/*
+ *	task_get_assignment
+ *
+ *	Return name of processor set that task is assigned to.
+ */
+kern_return_t task_get_assignment(
+	task_t		task,
+	processor_set_t	*pset)
+{
+	if (!task->active)
+		return KERN_FAILURE;
+
+	*pset = task->processor_set;
+	pset_reference(*pset);
+	return KERN_SUCCESS;
+}
+
+/*
+ *	task_priority
+ *
+ *	Set priority of task; used only for newly created threads.
+ *	Optionally change priorities of threads.
+ */
+kern_return_t
+task_priority(
+	task_t		task,
+	int		priority,
+	boolean_t	change_threads)
+{
+	kern_return_t	ret = KERN_SUCCESS;
+
+	if (task == TASK_NULL || invalid_pri(priority))
+		return KERN_INVALID_ARGUMENT;
+
+	task_lock(task);
+	task->priority = priority;
+
+	if (change_threads) {
+		register thread_t	thread;
+		register queue_head_t	*list;
+
+		list = &task->thread_list;
+		queue_iterate(list, thread, thread_t, thread_list) {
+			if (thread_priority(thread, priority, FALSE)
+				!= KERN_SUCCESS)
+					ret = KERN_FAILURE;
+		}
+	}
+
+	task_unlock(task);
+	return ret;
+}
+
+/*
+ *	task_collect_scan:
+ *
+ *	Attempt to free resources owned by tasks.
+ */
+
+void task_collect_scan(void)
+{
+	register task_t		task, prev_task;
+	processor_set_t		pset, prev_pset;
+
+	prev_task = TASK_NULL;
+	prev_pset = PROCESSOR_SET_NULL;
+
+	simple_lock(&all_psets_lock);
+	queue_iterate(&all_psets, pset, processor_set_t, all_psets) {
+		pset_lock(pset);
+		queue_iterate(&pset->tasks, task, task_t, pset_tasks) {
+			task_reference(task);
+			pset_reference(pset);
+			pset_unlock(pset);
+			simple_unlock(&all_psets_lock);
+
+			pmap_collect(task->map->pmap);
+
+			if (prev_task != TASK_NULL)
+				task_deallocate(prev_task);
+			prev_task = task;
+
+			if (prev_pset != PROCESSOR_SET_NULL)
+				pset_deallocate(prev_pset);
+			prev_pset = pset;
+
+			simple_lock(&all_psets_lock);
+			pset_lock(pset);
+		}
+		pset_unlock(pset);
+	}
+	simple_unlock(&all_psets_lock);
+
+	if (prev_task != TASK_NULL)
+		task_deallocate(prev_task);
+	if (prev_pset != PROCESSOR_SET_NULL)
+		pset_deallocate(prev_pset);
+}
+
+boolean_t task_collect_allowed = TRUE;
+unsigned task_collect_last_tick = 0;
+unsigned task_collect_max_rate = 0;		/* in ticks */
+
+/*
+ *	consider_task_collect:
+ *
+ *	Called by the pageout daemon when the system needs more free pages.
+ */
+
+void consider_task_collect(void)
+{
+	/*
+	 *	By default, don't attempt task collection more frequently
+	 *	than once a second.
+	 */
+
+	if (task_collect_max_rate == 0)
+		task_collect_max_rate = hz;
+
+	if (task_collect_allowed &&
+	    (sched_tick > (task_collect_last_tick + task_collect_max_rate))) {
+		task_collect_last_tick = sched_tick;
+		task_collect_scan();
+	}
+}
+
+kern_return_t
+task_ras_control(
+ 	task_t task,
+ 	vm_offset_t pc,
+ 	vm_offset_t endpc,
+	int flavor)
+{
+    kern_return_t ret = KERN_FAILURE;
+	
+#if	FAST_TAS
+    int i;
+
+    ret = KERN_SUCCESS;
+    task_lock(task);
+    switch (flavor)  {
+    case TASK_RAS_CONTROL_PURGE_ALL:  /* remove all RAS */
+	for (i = 0; i < TASK_FAST_TAS_NRAS; i++) {
+	    task->fast_tas_base[i] = task->fast_tas_end[i] = 0;
+	}
+	break;
+    case TASK_RAS_CONTROL_PURGE_ONE:  /* remove this RAS, collapse remaining */
+	for (i = 0; i < TASK_FAST_TAS_NRAS; i++)  {
+	    if ( (task->fast_tas_base[i] == pc)
+		&& (task->fast_tas_end[i] == endpc))  {
+			while (i < TASK_FAST_TAS_NRAS-1)  {
+	    		  task->fast_tas_base[i] = task->fast_tas_base[i+1];
+	    		  task->fast_tas_end[i] = task->fast_tas_end[i+1];
+			  i++;
+			 }
+	    		task->fast_tas_base[TASK_FAST_TAS_NRAS-1] = 0;
+	    		task->fast_tas_end[TASK_FAST_TAS_NRAS-1] = 0;
+			break;
+	     }
+	}
+	if (i == TASK_FAST_TAS_NRAS) {
+	    ret = KERN_INVALID_ADDRESS;
+	}
+	break;
+    case TASK_RAS_CONTROL_PURGE_ALL_AND_INSTALL_ONE: 
+	/* remove all RAS an install this RAS */
+	for (i = 0; i < TASK_FAST_TAS_NRAS; i++) {
+	    task->fast_tas_base[i] = task->fast_tas_end[i] = 0;
+	}
+	/* FALL THROUGH */
+    case TASK_RAS_CONTROL_INSTALL_ONE: /* install this RAS */
+	for (i = 0; i < TASK_FAST_TAS_NRAS; i++)  {
+	    if ( (task->fast_tas_base[i] == pc)
+	    && (task->fast_tas_end[i] == endpc))   {
+		/* already installed */
+		break;
+	    }
+	    if ((task->fast_tas_base[i] == 0) && (task->fast_tas_end[i] == 0)){
+		task->fast_tas_base[i] = pc;
+		task->fast_tas_end[i] = endpc;
+		break;
+	    }
+	}
+	if (i == TASK_FAST_TAS_NRAS)  {
+	    ret = KERN_RESOURCE_SHORTAGE;
+	} 
+	break;
+    default: ret = KERN_INVALID_VALUE;
+	break;
+    }
+    task_unlock(task);
+#endif
+    return ret;
+}