[apple/xnu.git] / osfmk / ipc / ipc_space.c

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. The rights granted to you under the License
 * may not be used to create, or enable the creation or redistribution of,
 * unlawful or unlicensed copies of an Apple operating system, or to
 * circumvent, violate, or enable the circumvention or violation of, any
 * terms of an Apple operating system software license agreement.
 * 
 * Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
 */
/*
 * @OSF_COPYRIGHT@
 */
/* 
 * Mach Operating System
 * Copyright (c) 1991,1990,1989 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:	ipc/ipc_space.c
 *	Author:	Rich Draves
 *	Date:	1989
 *
 *	Functions to manipulate IPC capability spaces.
 */

#include <mach_kdb.h>

#include <mach/boolean.h>
#include <mach/kern_return.h>
#include <mach/port.h>
#include <kern/assert.h>
#include <kern/sched_prim.h>
#include <kern/zalloc.h>
#include <ipc/port.h>
#include <ipc/ipc_entry.h>
#include <ipc/ipc_splay.h>
#include <ipc/ipc_object.h>
#include <ipc/ipc_hash.h>
#include <ipc/ipc_table.h>
#include <ipc/ipc_port.h>
#include <ipc/ipc_space.h>
#include <ipc/ipc_right.h>
#include <string.h>

zone_t ipc_space_zone;
ipc_space_t ipc_space_kernel;
ipc_space_t ipc_space_reply;
#if	MACH_KDB
ipc_space_t default_pager_space;
#endif	/* MACH_KDB */

/*
 *	Routine:	ipc_space_reference
 *	Routine:	ipc_space_release
 *	Purpose:
 *		Function versions of the IPC space macros.
 *		The "is_" cover macros can be defined to use the
 *		macros or the functions, as desired.
 */

void
ipc_space_reference(
	ipc_space_t	space)
{
	ipc_space_reference_macro(space);
}

void
ipc_space_release(
	ipc_space_t	space)
{
	ipc_space_release_macro(space);
}

/*
 *	Routine:	ipc_space_create
 *	Purpose:
 *		Creates a new IPC space.
 *
 *		The new space has two references, one for the caller
 *		and one because it is active.
 *	Conditions:
 *		Nothing locked.  Allocates memory.
 *	Returns:
 *		KERN_SUCCESS		Created a space.
 *		KERN_RESOURCE_SHORTAGE	Couldn't allocate memory.
 */

kern_return_t
ipc_space_create(
	ipc_table_size_t	initial,
	ipc_space_t		*spacep)
{
	ipc_space_t space;
	ipc_entry_t table;
	ipc_entry_num_t new_size;
	mach_port_index_t index;

	space = is_alloc();
	if (space == IS_NULL)
		return KERN_RESOURCE_SHORTAGE;

	table = it_entries_alloc(initial);
	if (table == IE_NULL) {
		is_free(space);
		return KERN_RESOURCE_SHORTAGE;
	}

	new_size = initial->its_size;
	memset((void *) table, 0, new_size * sizeof(struct ipc_entry));

	/*
	 *	Initialize the free list in the table.
	 *	Add the entries in reverse order, and
	 *	set the generation number to -1, so that
	 *	initial allocations produce "natural" names.
	 */
	for (index = 0; index < new_size; index++) {
		ipc_entry_t entry = &table[index];

		entry->ie_bits = IE_BITS_GEN_MASK;
		entry->ie_next = index+1;
	}
	table[new_size-1].ie_next = 0;

	is_ref_lock_init(space);
	space->is_references = 2;

	is_lock_init(space);
	space->is_active = TRUE;
	space->is_growing = FALSE;
	space->is_table = table;
	space->is_table_size = new_size;
	space->is_table_next = initial+1;

	ipc_splay_tree_init(&space->is_tree);
	space->is_tree_total = 0;
	space->is_tree_small = 0;
	space->is_tree_hash = 0;

	*spacep = space;
	return KERN_SUCCESS;
}

/*
 *	Routine:	ipc_space_create_special
 *	Purpose:
 *		Create a special space.  A special space
 *		doesn't hold rights in the normal way.
 *		Instead it is place-holder for holding
 *		disembodied (naked) receive rights.
 *		See ipc_port_alloc_special/ipc_port_dealloc_special.
 *	Conditions:
 *		Nothing locked.
 *	Returns:
 *		KERN_SUCCESS		Created a space.
 *		KERN_RESOURCE_SHORTAGE	Couldn't allocate memory.
 */

kern_return_t
ipc_space_create_special(
	ipc_space_t	*spacep)
{
	ipc_space_t space;

	space = is_alloc();
	if (space == IS_NULL)
		return KERN_RESOURCE_SHORTAGE;

	is_ref_lock_init(space);
	space->is_references = 1;

	is_lock_init(space);
	space->is_active = FALSE;

	*spacep = space;
	return KERN_SUCCESS;
}

/*
 * ipc_space_clean - remove all port references from an ipc space.
 *
 * In order to follow the traditional semantic, ipc_space_destroy
 * will not destroy the entire port table of a shared space.  Instead
 * it will simply clear its own sub-space.
 */
void
ipc_space_clean(
	ipc_space_t space)
{
	ipc_tree_entry_t tentry;
	ipc_entry_t table;
	ipc_entry_num_t size;
	mach_port_index_t index;

	/*
	 *	If somebody is trying to grow the table,
	 *	we must wait until they finish and figure
	 *	out the space died.
	 */
	is_write_lock(space);
	while (space->is_growing)
		is_write_sleep(space);

	/*
	 *	Now we can futz with it	since we have the write lock.
	 */
#if	MACH_KDB
	if (space == default_pager_space)
		default_pager_space = IS_NULL;
#endif	/* MACH_KDB */

	table = space->is_table;
	size = space->is_table_size;

	for (index = 0; index < size; index++) {
		ipc_entry_t entry = &table[index];
		mach_port_type_t type;

		type = IE_BITS_TYPE(entry->ie_bits);
		if (type != MACH_PORT_TYPE_NONE) {
			mach_port_name_t name =	MACH_PORT_MAKE(index,
						IE_BITS_GEN(entry->ie_bits));
			ipc_right_destroy(space, name, entry);
		}
	}

	/*
	 * JMM - Now the table is cleaned out.  We don't bother shrinking the
	 * size of the table at this point, but we probably should if it is
	 * really large.  Lets just clean up the splay tree.
	 */
 start_splay:
	for (tentry = ipc_splay_traverse_start(&space->is_tree);
	     tentry != ITE_NULL;
	     tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
		mach_port_type_t type;
		mach_port_name_t name = tentry->ite_name;

		type = IE_BITS_TYPE(tentry->ite_bits);
		/*
		 * If it is a real right, then destroy it.  This will have the
		 * side effect of removing it from the splay, so start over.
		 */
		if(type != MACH_PORT_TYPE_NONE) {
			ipc_splay_traverse_finish(&space->is_tree);
			ipc_right_destroy(space, name, &tentry->ite_entry);
			goto start_splay;
		}
	}
	ipc_splay_traverse_finish(&space->is_tree);
	is_write_unlock(space);
}


/*
 *	Routine:	ipc_space_destroy
 *	Purpose:
 *		Marks the space as dead and cleans up the entries.
 *		Does nothing if the space is already dead.
 *	Conditions:
 *		Nothing locked.
 */

void
ipc_space_destroy(
	ipc_space_t	space)
{
	boolean_t active;
	ipc_tree_entry_t tentry;
	ipc_entry_t table;
	ipc_entry_num_t size;
	mach_port_index_t index;

	assert(space != IS_NULL);

	is_write_lock(space);
	active = space->is_active;
	space->is_active = FALSE;
	is_write_unlock(space);

	if (!active)
		return;


	/*
	 *	If somebody is trying to grow the table,
	 *	we must wait until they finish and figure
	 *	out the space died.
	 */
	is_read_lock(space);
	while (space->is_growing)
		is_read_sleep(space);

	is_read_unlock(space);
	/*
	 *	Now we can futz with it	unlocked.
	 */
#if	MACH_KDB
	if (space == default_pager_space)
		default_pager_space = IS_NULL;
#endif	/* MACH_KDB */

	table = space->is_table;
	size = space->is_table_size;

	for (index = 0; index < size; index++) {
		ipc_entry_t entry = &table[index];
		mach_port_type_t type;

		type = IE_BITS_TYPE(entry->ie_bits);
		if (type != MACH_PORT_TYPE_NONE) {
			mach_port_name_t name;

			name = MACH_PORT_MAKE(index,
					      IE_BITS_GEN(entry->ie_bits));
			ipc_right_clean(space, name, entry);
		}
	}

	it_entries_free(space->is_table_next-1, table);
	space->is_table_size = 0;

	for (tentry = ipc_splay_traverse_start(&space->is_tree);
	     tentry != ITE_NULL;
	     tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
		mach_port_type_t type;
		mach_port_name_t name = tentry->ite_name;

		type = IE_BITS_TYPE(tentry->ite_bits);
		assert(type != MACH_PORT_TYPE_NONE);

		ipc_right_clean(space, name, &tentry->ite_entry);

		if(type == MACH_PORT_TYPE_SEND)
			ipc_hash_global_delete(space, tentry->ite_object,
					       name, tentry);
	}
	ipc_splay_traverse_finish(&space->is_tree);

	/*
	 *	Because the space is now dead,
	 *	we must release the "active" reference for it.
	 *	Our caller still has his reference.
	 */
	is_release(space);
}
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
8f6c56a5	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
1c79356b	5	*
8f6c56a5 A	6	* This file contains Original Code and/or Modifications of Original Code
	7	* as defined in and that are subject to the Apple Public Source License
	8	* Version 2.0 (the 'License'). You may not use this file except in
	9	* compliance with the License. The rights granted to you under the License
	10	* may not be used to create, or enable the creation or redistribution of,
	11	* unlawful or unlicensed copies of an Apple operating system, or to
	12	* circumvent, violate, or enable the circumvention or violation of, any
	13	* terms of an Apple operating system software license agreement.
	14	*
	15	* Please obtain a copy of the License at
	16	* http://www.opensource.apple.com/apsl/ and read it before using this file.
	17	*
	18	* The Original Code and all software distributed under the License are
	19	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
8ad349bb	24	* limitations under the License.
8f6c56a5 A	25	*
8f6c56a5 A	26	* @APPLE_OSREFERENCE_LICENSE_HEADER_END@
1c79356b A	27	*/
	28	/*
	29	* @OSF_COPYRIGHT@
	30	*/
	31	/*
	32	* Mach Operating System
	33	* Copyright (c) 1991,1990,1989 Carnegie Mellon University
	34	* All Rights Reserved.
	35	*
	36	* Permission to use, copy, modify and distribute this software and its
	37	* documentation is hereby granted, provided that both the copyright
	38	* notice and this permission notice appear in all copies of the
	39	* software, derivative works or modified versions, and any portions
	40	* thereof, and that both notices appear in supporting documentation.
	41	*
	42	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	43	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	44	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	45	*
	46	* Carnegie Mellon requests users of this software to return to
	47	*
	48	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	49	* School of Computer Science
	50	* Carnegie Mellon University
	51	* Pittsburgh PA 15213-3890
	52	*
	53	* any improvements or extensions that they make and grant Carnegie Mellon
	54	* the rights to redistribute these changes.
	55	*/
	56	/*
	57	*/
	58	/*
	59	* File: ipc/ipc_space.c
	60	* Author: Rich Draves
	61	* Date: 1989
	62	*
	63	* Functions to manipulate IPC capability spaces.
	64	*/
	65
	66	#include <mach_kdb.h>
	67
	68	#include <mach/boolean.h>
	69	#include <mach/kern_return.h>
	70	#include <mach/port.h>
	71	#include <kern/assert.h>
	72	#include <kern/sched_prim.h>
	73	#include <kern/zalloc.h>
	74	#include <ipc/port.h>
	75	#include <ipc/ipc_entry.h>
	76	#include <ipc/ipc_splay.h>
	77	#include <ipc/ipc_object.h>
	78	#include <ipc/ipc_hash.h>
	79	#include <ipc/ipc_table.h>
	80	#include <ipc/ipc_port.h>
	81	#include <ipc/ipc_space.h>
	82	#include <ipc/ipc_right.h>
	83	#include <string.h>
	84
	85	zone_t ipc_space_zone;
	86	ipc_space_t ipc_space_kernel;
	87	ipc_space_t ipc_space_reply;
	88	#if MACH_KDB
	89	ipc_space_t default_pager_space;
	90	#endif /* MACH_KDB */
91
92	/*
93	* Routine: ipc_space_reference
94	* Routine: ipc_space_release
95	* Purpose:
96	* Function versions of the IPC space macros.
97	* The "is_" cover macros can be defined to use the
98	* macros or the functions, as desired.
99	*/
100
101	void
102	ipc_space_reference(
103	ipc_space_t space)
104	{
105	ipc_space_reference_macro(space);
106	}
107
108	void
109	ipc_space_release(
110	ipc_space_t space)
111	{
112	ipc_space_release_macro(space);
113	}
114
115	/*
116	* Routine: ipc_space_create
117	* Purpose:
118	* Creates a new IPC space.
119	*
120	* The new space has two references, one for the caller
121	* and one because it is active.
122	* Conditions:
123	* Nothing locked. Allocates memory.
124	* Returns:
125	* KERN_SUCCESS Created a space.
126	* KERN_RESOURCE_SHORTAGE Couldn't allocate memory.
127	*/
128
129	kern_return_t
130	ipc_space_create(
131	ipc_table_size_t initial,
132	ipc_space_t *spacep)
133	{
134	ipc_space_t space;
135	ipc_entry_t table;
136	ipc_entry_num_t new_size;
137	mach_port_index_t index;
138
139	space = is_alloc();
140	if (space == IS_NULL)
141	return KERN_RESOURCE_SHORTAGE;
142
143	table = it_entries_alloc(initial);
144	if (table == IE_NULL) {
145	is_free(space);
146	return KERN_RESOURCE_SHORTAGE;
147	}
148
149	new_size = initial->its_size;
150	memset((void ) table, 0, new_size sizeof(struct ipc_entry));
151
152	/*
153	* Initialize the free list in the table.
154	* Add the entries in reverse order, and
155	* set the generation number to -1, so that
156	* initial allocations produce "natural" names.
157	*/
158	for (index = 0; index < new_size; index++) {
159	ipc_entry_t entry = &table[index];
160
161	entry->ie_bits = IE_BITS_GEN_MASK;
162	entry->ie_next = index+1;
163	}
164	table[new_size-1].ie_next = 0;
165
166	is_ref_lock_init(space);
167	space->is_references = 2;
168
169	is_lock_init(space);
170	space->is_active = TRUE;
171	space->is_growing = FALSE;
172	space->is_table = table;
173	space->is_table_size = new_size;
174	space->is_table_next = initial+1;
175
176	ipc_splay_tree_init(&space->is_tree);
177	space->is_tree_total = 0;
178	space->is_tree_small = 0;
179	space->is_tree_hash = 0;
180
181	*spacep = space;
182	return KERN_SUCCESS;
183	}
184
185	/*
186	* Routine: ipc_space_create_special
187	* Purpose:
188	* Create a special space. A special space
189	* doesn't hold rights in the normal way.
190	* Instead it is place-holder for holding
191	* disembodied (naked) receive rights.
192	* See ipc_port_alloc_special/ipc_port_dealloc_special.
193	* Conditions:
194	* Nothing locked.
195	* Returns:
196	* KERN_SUCCESS Created a space.
197	* KERN_RESOURCE_SHORTAGE Couldn't allocate memory.
198	*/
199
200	kern_return_t
201	ipc_space_create_special(
202	ipc_space_t *spacep)
203	{
204	ipc_space_t space;
205
206	space = is_alloc();
207	if (space == IS_NULL)
208	return KERN_RESOURCE_SHORTAGE;
209
210	is_ref_lock_init(space);
211	space->is_references = 1;
212
213	is_lock_init(space);
214	space->is_active = FALSE;
215
216	*spacep = space;
217	return KERN_SUCCESS;
218	}
219
220	/*
221	* ipc_space_clean - remove all port references from an ipc space.
222	*
223	* In order to follow the traditional semantic, ipc_space_destroy
224	* will not destroy the entire port table of a shared space. Instead
225	* it will simply clear its own sub-space.
226	*/
227	void
228	ipc_space_clean(
229	ipc_space_t space)
230	{
231	ipc_tree_entry_t tentry;
232	ipc_entry_t table;
233	ipc_entry_num_t size;
234	mach_port_index_t index;
235
236	/*
237	* If somebody is trying to grow the table,
238	* we must wait until they finish and figure
239	* out the space died.
240	*/
241	is_write_lock(space);
9bccf70c A	242	while (space->is_growing)
9bccf70c A	243	is_write_sleep(space);
1c79356b A	244
	245	/*
	246	* Now we can futz with it since we have the write lock.
	247	*/
	248	#if MACH_KDB
	249	if (space == default_pager_space)
	250	default_pager_space = IS_NULL;
	251	#endif /* MACH_KDB */
	252
	253	table = space->is_table;
	254	size = space->is_table_size;
	255
	256	for (index = 0; index < size; index++) {
	257	ipc_entry_t entry = &table[index];
	258	mach_port_type_t type;
	259
	260	type = IE_BITS_TYPE(entry->ie_bits);
	261	if (type != MACH_PORT_TYPE_NONE) {
	262	mach_port_name_t name = MACH_PORT_MAKE(index,
	263	IE_BITS_GEN(entry->ie_bits));
	264	ipc_right_destroy(space, name, entry);
	265	}
	266	}
	267
	268	/*
	269	* JMM - Now the table is cleaned out. We don't bother shrinking the
	270	* size of the table at this point, but we probably should if it is
	271	* really large. Lets just clean up the splay tree.
	272	*/
	273	start_splay:
	274	for (tentry = ipc_splay_traverse_start(&space->is_tree);
	275	tentry != ITE_NULL;
	276	tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
1c79356b A	277	mach_port_type_t type;
	278	mach_port_name_t name = tentry->ite_name;
	279
	280	type = IE_BITS_TYPE(tentry->ite_bits);
	281	/*
	282	* If it is a real right, then destroy it. This will have the
	283	* side effect of removing it from the splay, so start over.
	284	*/
	285	if(type != MACH_PORT_TYPE_NONE) {
	286	ipc_splay_traverse_finish(&space->is_tree);
	287	ipc_right_destroy(space, name, &tentry->ite_entry);
	288	goto start_splay;
	289	}
	290	}
	291	ipc_splay_traverse_finish(&space->is_tree);
	292	is_write_unlock(space);
	293	}
	294
	295
	296	/*
	297	* Routine: ipc_space_destroy
	298	* Purpose:
	299	* Marks the space as dead and cleans up the entries.
	300	* Does nothing if the space is already dead.
	301	* Conditions:
	302	* Nothing locked.
	303	*/
	304
	305	void
	306	ipc_space_destroy(
	307	ipc_space_t space)
	308	{
	309	boolean_t active;
	310	ipc_tree_entry_t tentry;
	311	ipc_entry_t table;
	312	ipc_entry_num_t size;
	313	mach_port_index_t index;
	314
	315	assert(space != IS_NULL);
	316
	317	is_write_lock(space);
	318	active = space->is_active;
	319	space->is_active = FALSE;
	320	is_write_unlock(space);
	321
	322	if (!active)
	323	return;
	324
	325
	326	/*
	327	* If somebody is trying to grow the table,
	328	* we must wait until they finish and figure
	329	* out the space died.
	330	*/
	331	is_read_lock(space);
9bccf70c A	332	while (space->is_growing)
9bccf70c A	333	is_read_sleep(space);
1c79356b A	334
	335	is_read_unlock(space);
	336	/*
	337	* Now we can futz with it unlocked.
	338	*/
	339	#if MACH_KDB
	340	if (space == default_pager_space)
	341	default_pager_space = IS_NULL;
	342	#endif /* MACH_KDB */
	343
	344	table = space->is_table;
	345	size = space->is_table_size;
	346
	347	for (index = 0; index < size; index++) {
	348	ipc_entry_t entry = &table[index];
	349	mach_port_type_t type;
	350
	351	type = IE_BITS_TYPE(entry->ie_bits);
	352	if (type != MACH_PORT_TYPE_NONE) {
	353	mach_port_name_t name;
	354
	355	name = MACH_PORT_MAKE(index,
	356	IE_BITS_GEN(entry->ie_bits));
	357	ipc_right_clean(space, name, entry);
	358	}
	359	}
	360
	361	it_entries_free(space->is_table_next-1, table);
	362	space->is_table_size = 0;
	363
	364	for (tentry = ipc_splay_traverse_start(&space->is_tree);
	365	tentry != ITE_NULL;
	366	tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
	367	mach_port_type_t type;
	368	mach_port_name_t name = tentry->ite_name;
	369
	370	type = IE_BITS_TYPE(tentry->ite_bits);
	371	assert(type != MACH_PORT_TYPE_NONE);
	372
	373	ipc_right_clean(space, name, &tentry->ite_entry);
	374
	375	if(type == MACH_PORT_TYPE_SEND)
	376	ipc_hash_global_delete(space, tentry->ite_object,
	377	name, tentry);
	378	}
	379	ipc_splay_traverse_finish(&space->is_tree);
	380
	381	/*
	382	* Because the space is now dead,
	383	* we must release the "active" reference for it.
	384	* Our caller still has his reference.
	385	*/
	386	is_release(space);
	387	}
91447636 A	388
91447636 A	389