[apple/xnu.git] / osfmk / ipc / ipc_kmsg.h

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * 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. 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_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_kmsg.h
 *	Author:	Rich Draves
 *	Date:	1989
 *
 *	Definitions for kernel messages.
 */

#ifndef	_IPC_IPC_KMSG_H_
#define _IPC_IPC_KMSG_H_

#include <cpus.h>

#include <mach/vm_types.h>
#include <mach/message.h>
#include <kern/assert.h>
#include <kern/cpu_number.h>
#include <kern/macro_help.h>
#include <kern/kalloc.h>
#include <ipc/ipc_object.h>

/*
 *	This structure is only the header for a kmsg buffer;
 *	the actual buffer is normally larger.  The rest of the buffer
 *	holds the body of the message.
 *
 *	In a kmsg, the port fields hold pointers to ports instead
 *	of port names.  These pointers hold references.
 *
 *	The ikm_header.msgh_remote_port field is the destination
 *	of the message.
 */


typedef struct ipc_kmsg {
	struct ipc_kmsg *ikm_next;
	struct ipc_kmsg *ikm_prev;
	ipc_port_t ikm_prealloc;	/* port we were preallocated from */
	mach_msg_size_t ikm_size;
	mach_msg_header_t ikm_header;
} *ipc_kmsg_t;

#define	IKM_NULL		((ipc_kmsg_t) 0)

#define	IKM_OVERHEAD							\
		(sizeof(struct ipc_kmsg) - sizeof(mach_msg_header_t))

#define	ikm_plus_overhead(size)	((mach_msg_size_t)((size) + IKM_OVERHEAD))
#define	ikm_less_overhead(size)	((mach_msg_size_t)((size) - IKM_OVERHEAD))

/*
 * XXX	For debugging.
 */
#define IKM_BOGUS		((ipc_kmsg_t) 0xffffff10)

/*
 *	The size of the kernel message buffers that will be cached.
 *	IKM_SAVED_KMSG_SIZE includes overhead; IKM_SAVED_MSG_SIZE doesn't.
 */

#define	IKM_SAVED_MSG_SIZE	ikm_less_overhead(256)

#define	ikm_prealloc_inuse_port(kmsg)					\
	((kmsg)->ikm_prealloc)

#define	ikm_prealloc_inuse(kmsg)					\
	((kmsg)->ikm_prealloc != IP_NULL)

#define	ikm_prealloc_set_inuse(kmsg, port)				\
MACRO_BEGIN								\
	assert((port) != IP_NULL);					\
	(kmsg)->ikm_prealloc = (port);					\
	ip_reference(port);						\
MACRO_END

#define ikm_prealloc_clear_inuse(kmsg, port)				\
MACRO_BEGIN								\
	(kmsg)->ikm_prealloc = IP_NULL;					\
	ip_release(port);						\
MACRO_END


#define	ikm_init(kmsg, size)						\
MACRO_BEGIN								\
	(kmsg)->ikm_size = (size);					\
	(kmsg)->ikm_prealloc = IP_NULL;					\
	assert((kmsg)->ikm_prev = (kmsg)->ikm_next = IKM_BOGUS);	\
MACRO_END

#define	ikm_check_init(kmsg, size)					\
MACRO_BEGIN								\
	assert((kmsg)->ikm_size == (size));				\
	assert((kmsg)->ikm_prev == IKM_BOGUS);				\
	assert((kmsg)->ikm_next == IKM_BOGUS);				\
MACRO_END

struct ipc_kmsg_queue {
	struct ipc_kmsg *ikmq_base;
};

typedef struct ipc_kmsg_queue *ipc_kmsg_queue_t;

#define	IKMQ_NULL		((ipc_kmsg_queue_t) 0)


/*
 * Exported interfaces
 */

#define	ipc_kmsg_queue_init(queue)		\
MACRO_BEGIN					\
	(queue)->ikmq_base = IKM_NULL;		\
MACRO_END

#define	ipc_kmsg_queue_empty(queue)	((queue)->ikmq_base == IKM_NULL)

/* Enqueue a kmsg */
extern void ipc_kmsg_enqueue(
	ipc_kmsg_queue_t	queue,
	ipc_kmsg_t		kmsg);

/* Dequeue and return a kmsg */
extern ipc_kmsg_t ipc_kmsg_dequeue(
	ipc_kmsg_queue_t        queue);

/* Pull a kmsg out of a queue */
extern void ipc_kmsg_rmqueue(
	ipc_kmsg_queue_t	queue,
	ipc_kmsg_t		kmsg);

#define	ipc_kmsg_queue_first(queue)		((queue)->ikmq_base)

/* Return the kmsg following the given kmsg */
extern ipc_kmsg_t ipc_kmsg_queue_next(
	ipc_kmsg_queue_t	queue,
	ipc_kmsg_t		kmsg);

#define	ipc_kmsg_rmqueue_first_macro(queue, kmsg)			\
MACRO_BEGIN								\
	register ipc_kmsg_t _next;					\
									\
	assert((queue)->ikmq_base == (kmsg));				\
									\
	_next = (kmsg)->ikm_next;					\
	if (_next == (kmsg)) {						\
		assert((kmsg)->ikm_prev == (kmsg));			\
		(queue)->ikmq_base = IKM_NULL;				\
	} else {							\
		register ipc_kmsg_t _prev = (kmsg)->ikm_prev;		\
									\
		(queue)->ikmq_base = _next;				\
		_next->ikm_prev = _prev;				\
		_prev->ikm_next = _next;				\
	}								\
  	/* XXX Debug paranoia ASSIGNMENTS */				\
  	assert(kmsg->ikm_next = IKM_BOGUS);				\
  	assert(kmsg->ikm_prev = IKM_BOGUS);				\
MACRO_END

#define	ipc_kmsg_enqueue_macro(queue, kmsg)				\
MACRO_BEGIN								\
	register ipc_kmsg_t _first = (queue)->ikmq_base;		\
									\
	if (_first == IKM_NULL) {					\
		(queue)->ikmq_base = (kmsg);				\
		(kmsg)->ikm_next = (kmsg);				\
		(kmsg)->ikm_prev = (kmsg);				\
	} else {							\
		register ipc_kmsg_t _last = _first->ikm_prev;		\
									\
		(kmsg)->ikm_next = _first;				\
		(kmsg)->ikm_prev = _last;				\
		_first->ikm_prev = (kmsg);				\
		_last->ikm_next = (kmsg);				\
	}								\
MACRO_END

/* scatter list macros */

#define SKIP_PORT_DESCRIPTORS(s, e)					\
MACRO_BEGIN								\
	if ((s) != MACH_MSG_DESCRIPTOR_NULL) {				\
		while ((s) < (e)) {					\
			if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR)	\
				break;					\
			(s)++;						\
		}							\
		if ((s) >= (e))						\
			(s) = MACH_MSG_DESCRIPTOR_NULL;			\
	}								\
MACRO_END

#define INCREMENT_SCATTER(s)						\
MACRO_BEGIN								\
	if ((s) != MACH_MSG_DESCRIPTOR_NULL) {				\
		(s)++;							\
	}								\
MACRO_END

/*
 *	extern void
 *	ipc_kmsg_send_always(ipc_kmsg_t);
 *
 *	Unfortunately, to avoid warnings/lint about unused variables
 *	when assertions are turned off, we need two versions of this.
 */
#if	MACH_ASSERT

#define	ipc_kmsg_send_always(kmsg)					\
MACRO_BEGIN								\
	mach_msg_return_t mr;						\
									\
	mr = ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS,			\
			     MACH_MSG_TIMEOUT_NONE);			\
	assert(mr == MACH_MSG_SUCCESS);					\
MACRO_END

#else	/* MACH_ASSERT */

#define	ipc_kmsg_send_always(kmsg)					\
MACRO_BEGIN								\
	(void) ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS,			\
			       MACH_MSG_TIMEOUT_NONE);			\
MACRO_END

#endif	/* MACH_ASSERT */

/* Allocate a kernel message */
extern ipc_kmsg_t ipc_kmsg_alloc(
        mach_msg_size_t size);

/* Free a kernel message buffer */
extern void ipc_kmsg_free(
	ipc_kmsg_t	kmsg);

/* Destroy kernel message */
extern void ipc_kmsg_destroy(
	ipc_kmsg_t	kmsg);

/* Preallocate a kernel message buffer */
extern void ipc_kmsg_set_prealloc(
	ipc_kmsg_t	kmsg,
	ipc_port_t	port);

/* Clear a kernel message buffer */
extern void ipc_kmsg_clear_prealloc(
	ipc_kmsg_t	kmsg,
	ipc_port_t	port);

/* Allocate a kernel message buffer and copy a user message to the buffer */
extern mach_msg_return_t ipc_kmsg_get(
	mach_msg_header_t	*msg,
	mach_msg_size_t		size,
	ipc_kmsg_t		*kmsgp);

/* Allocate a kernel message buffer and copy a kernel message to the buffer */
extern mach_msg_return_t ipc_kmsg_get_from_kernel(
	mach_msg_header_t	*msg,
	mach_msg_size_t		size,
	ipc_kmsg_t		*kmsgp);

/* Send a message to a port */
extern mach_msg_return_t ipc_kmsg_send(
	ipc_kmsg_t		kmsg,
	mach_msg_option_t	option,
	mach_msg_timeout_t	timeout);

/* Copy a kernel message buffer to a user message */
extern mach_msg_return_t ipc_kmsg_put(
	mach_msg_header_t	*msg,
	ipc_kmsg_t		kmsg,
	mach_msg_size_t		size);

/* Copy a kernel message buffer to a kernel message */
extern void ipc_kmsg_put_to_kernel(
	mach_msg_header_t	*msg,
	ipc_kmsg_t		kmsg,
	mach_msg_size_t		size);

/* Copyin port rights in the header of a message */
extern mach_msg_return_t ipc_kmsg_copyin_header(
	mach_msg_header_t	*msg,
	ipc_space_t		space,
	mach_port_name_t	notify);

/* Copyin port rights and out-of-line memory from a user message */
extern mach_msg_return_t ipc_kmsg_copyin(
	ipc_kmsg_t		kmsg,
	ipc_space_t		space,
	vm_map_t		map,
	mach_port_name_t	notify);

/* Copyin port rights and out-of-line memory from a kernel message */
extern void ipc_kmsg_copyin_from_kernel(
	ipc_kmsg_t		kmsg);

/* Copyout port rights in the header of a message */
extern mach_msg_return_t ipc_kmsg_copyout_header(
	mach_msg_header_t	*msg,
	ipc_space_t		space,
	mach_port_name_t	notify);

/* Copyout a port right returning a name */
extern mach_msg_return_t ipc_kmsg_copyout_object(
	ipc_space_t		space,
	ipc_object_t		object,
	mach_msg_type_name_t	msgt_name,
	mach_port_name_t	*namep);

/* Copyout the header and body to a user message */
extern mach_msg_return_t ipc_kmsg_copyout(
	ipc_kmsg_t		kmsg,
	ipc_space_t		space,
	vm_map_t		map,
	mach_port_name_t	notify,
	mach_msg_body_t		*slist);

/* Copyout port rights and out-of-line memory from the body of a message */
extern mach_msg_return_t ipc_kmsg_copyout_body(
    	ipc_kmsg_t		kmsg,
	ipc_space_t		space,
	vm_map_t		map,
	mach_msg_body_t		*slist);

/* Copyout port rights and out-of-line memory to a user message,
   not reversing the ports in the header */
extern mach_msg_return_t ipc_kmsg_copyout_pseudo(
	ipc_kmsg_t		kmsg,
	ipc_space_t		space,
	vm_map_t		map,
	mach_msg_body_t		*slist);

/* Copyout the destination port in the message */
extern void ipc_kmsg_copyout_dest( 
	ipc_kmsg_t		kmsg,
	ipc_space_t		space);

/* kernel's version of ipc_kmsg_copyout_dest */
extern void ipc_kmsg_copyout_to_kernel(
	ipc_kmsg_t		kmsg,
	ipc_space_t		space);

/* copyin a scatter list and check consistency */
extern mach_msg_body_t *ipc_kmsg_copyin_scatter(
        mach_msg_header_t       *msg,
        mach_msg_size_t         slist_size,
        ipc_kmsg_t              kmsg);

/* free a scatter list */
extern void ipc_kmsg_free_scatter(
        mach_msg_body_t 	*slist,
        mach_msg_size_t		slist_size);

#include <mach_kdb.h>
#if 	MACH_KDB

/* Do a formatted dump of a kernel message */
extern void ipc_kmsg_print(
	ipc_kmsg_t	kmsg);

/* Do a formatted dump of a user message */
extern void ipc_msg_print(
	mach_msg_header_t	*msgh);

#endif	/* MACH_KDB */

#endif	/* _IPC_IPC_KMSG_H_ */
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
d7e50217	6	* Copyright (c) 1999-2003 Apple Computer, Inc. All Rights Reserved.
1c79356b	7	*
d7e50217 A	8	* This file contains Original Code and/or Modifications of Original Code
	9	* as defined in and that are subject to the Apple Public Source License
	10	* Version 2.0 (the 'License'). You may not use this file except in
	11	* compliance with the License. Please obtain a copy of the License at
	12	* http://www.opensource.apple.com/apsl/ and read it before using this
	13	* file.
	14	*
	15	* The Original Code and all software distributed under the License are
	16	* distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	17	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	18	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
d7e50217 A	19	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	20	* Please see the License for the specific language governing rights and
	21	* limitations under the License.
1c79356b A	22	*
	23	* @APPLE_LICENSE_HEADER_END@
	24	*/
	25	/*
	26	* @OSF_COPYRIGHT@
	27	*/
	28	/*
	29	* Mach Operating System
	30	* Copyright (c) 1991,1990,1989 Carnegie Mellon University
	31	* All Rights Reserved.
	32	*
	33	* Permission to use, copy, modify and distribute this software and its
	34	* documentation is hereby granted, provided that both the copyright
	35	* notice and this permission notice appear in all copies of the
	36	* software, derivative works or modified versions, and any portions
	37	* thereof, and that both notices appear in supporting documentation.
	38	*
	39	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	40	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	41	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	42	*
	43	* Carnegie Mellon requests users of this software to return to
	44	*
	45	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	46	* School of Computer Science
	47	* Carnegie Mellon University
	48	* Pittsburgh PA 15213-3890
	49	*
	50	* any improvements or extensions that they make and grant Carnegie Mellon
	51	* the rights to redistribute these changes.
	52	*/
	53	/*
	54	*/
	55	/*
	56	* File: ipc/ipc_kmsg.h
	57	* Author: Rich Draves
	58	* Date: 1989
	59	*
	60	* Definitions for kernel messages.
	61	*/
	62
	63	#ifndef _IPC_IPC_KMSG_H_
	64	#define _IPC_IPC_KMSG_H_
	65
	66	#include <cpus.h>
	67
	68	#include <mach/vm_types.h>
	69	#include <mach/message.h>
	70	#include <kern/assert.h>
	71	#include <kern/cpu_number.h>
	72	#include <kern/macro_help.h>
	73	#include <kern/kalloc.h>
	74	#include <ipc/ipc_object.h>
	75
	76	/*
	77	* This structure is only the header for a kmsg buffer;
	78	* the actual buffer is normally larger. The rest of the buffer
	79	* holds the body of the message.
	80	*
	81	* In a kmsg, the port fields hold pointers to ports instead
	82	* of port names. These pointers hold references.
	83	*
	84	* The ikm_header.msgh_remote_port field is the destination
	85	* of the message.
86	*/
87
88
89	typedef struct ipc_kmsg {
90	struct ipc_kmsg *ikm_next;
91	struct ipc_kmsg *ikm_prev;
92	ipc_port_t ikm_prealloc; /* port we were preallocated from */
93	mach_msg_size_t ikm_size;
94	mach_msg_header_t ikm_header;
95	} *ipc_kmsg_t;
96
97	#define IKM_NULL ((ipc_kmsg_t) 0)
98
99	#define IKM_OVERHEAD \
100	(sizeof(struct ipc_kmsg) - sizeof(mach_msg_header_t))
101
102	#define ikm_plus_overhead(size) ((mach_msg_size_t)((size) + IKM_OVERHEAD))
103	#define ikm_less_overhead(size) ((mach_msg_size_t)((size) - IKM_OVERHEAD))
104
105	/*
106	* XXX For debugging.
107	*/
108	#define IKM_BOGUS ((ipc_kmsg_t) 0xffffff10)
109
110	/*
111	* The size of the kernel message buffers that will be cached.
112	* IKM_SAVED_KMSG_SIZE includes overhead; IKM_SAVED_MSG_SIZE doesn't.
113	*/
114
115	#define IKM_SAVED_MSG_SIZE ikm_less_overhead(256)
116
117	#define ikm_prealloc_inuse_port(kmsg) \
118	((kmsg)->ikm_prealloc)
119
120	#define ikm_prealloc_inuse(kmsg) \
121	((kmsg)->ikm_prealloc != IP_NULL)
122
123	#define ikm_prealloc_set_inuse(kmsg, port) \
124	MACRO_BEGIN \
9bccf70c A	125	assert((port) != IP_NULL); \
	126	(kmsg)->ikm_prealloc = (port); \
	127	ip_reference(port); \
1c79356b A	128	MACRO_END
	129
	130	#define ikm_prealloc_clear_inuse(kmsg, port) \
	131	MACRO_BEGIN \
	132	(kmsg)->ikm_prealloc = IP_NULL; \
9bccf70c	133	ip_release(port); \
1c79356b A	134	MACRO_END
	135
	136
	137	#define ikm_init(kmsg, size) \
	138	MACRO_BEGIN \
	139	(kmsg)->ikm_size = (size); \
	140	(kmsg)->ikm_prealloc = IP_NULL; \
	141	assert((kmsg)->ikm_prev = (kmsg)->ikm_next = IKM_BOGUS); \
	142	MACRO_END
	143
	144	#define ikm_check_init(kmsg, size) \
	145	MACRO_BEGIN \
	146	assert((kmsg)->ikm_size == (size)); \
	147	assert((kmsg)->ikm_prev == IKM_BOGUS); \
	148	assert((kmsg)->ikm_next == IKM_BOGUS); \
	149	MACRO_END
	150
	151	struct ipc_kmsg_queue {
	152	struct ipc_kmsg *ikmq_base;
	153	};
	154
	155	typedef struct ipc_kmsg_queue *ipc_kmsg_queue_t;
	156
	157	#define IKMQ_NULL ((ipc_kmsg_queue_t) 0)
	158
	159
	160	/*
	161	* Exported interfaces
	162	*/
	163
	164	#define ipc_kmsg_queue_init(queue) \
	165	MACRO_BEGIN \
	166	(queue)->ikmq_base = IKM_NULL; \
	167	MACRO_END
	168
	169	#define ipc_kmsg_queue_empty(queue) ((queue)->ikmq_base == IKM_NULL)
	170
	171	/* Enqueue a kmsg */
	172	extern void ipc_kmsg_enqueue(
	173	ipc_kmsg_queue_t queue,
	174	ipc_kmsg_t kmsg);
	175
	176	/* Dequeue and return a kmsg */
	177	extern ipc_kmsg_t ipc_kmsg_dequeue(
	178	ipc_kmsg_queue_t queue);
	179
	180	/* Pull a kmsg out of a queue */
	181	extern void ipc_kmsg_rmqueue(
	182	ipc_kmsg_queue_t queue,
	183	ipc_kmsg_t kmsg);
	184
	185	#define ipc_kmsg_queue_first(queue) ((queue)->ikmq_base)
	186
	187	/* Return the kmsg following the given kmsg */
	188	extern ipc_kmsg_t ipc_kmsg_queue_next(
	189	ipc_kmsg_queue_t queue,
	190	ipc_kmsg_t kmsg);
	191
	192	#define ipc_kmsg_rmqueue_first_macro(queue, kmsg) \
	193	MACRO_BEGIN \
	194	register ipc_kmsg_t _next; \
	195	\
	196	assert((queue)->ikmq_base == (kmsg)); \
	197	\
198	_next = (kmsg)->ikm_next; \
199	if (_next == (kmsg)) { \
200	assert((kmsg)->ikm_prev == (kmsg)); \
201	(queue)->ikmq_base = IKM_NULL; \
202	} else { \
203	register ipc_kmsg_t _prev = (kmsg)->ikm_prev; \
204	\
205	(queue)->ikmq_base = _next; \
206	_next->ikm_prev = _prev; \
207	_prev->ikm_next = _next; \
208	} \
209	/* XXX Debug paranoia ASSIGNMENTS */ \
210	assert(kmsg->ikm_next = IKM_BOGUS); \
211	assert(kmsg->ikm_prev = IKM_BOGUS); \
212	MACRO_END
213
214	#define ipc_kmsg_enqueue_macro(queue, kmsg) \
215	MACRO_BEGIN \
216	register ipc_kmsg_t _first = (queue)->ikmq_base; \
217	\
218	if (_first == IKM_NULL) { \
219	(queue)->ikmq_base = (kmsg); \
220	(kmsg)->ikm_next = (kmsg); \
221	(kmsg)->ikm_prev = (kmsg); \
222	} else { \
223	register ipc_kmsg_t _last = _first->ikm_prev; \
224	\
225	(kmsg)->ikm_next = _first; \
226	(kmsg)->ikm_prev = _last; \
227	_first->ikm_prev = (kmsg); \
228	_last->ikm_next = (kmsg); \
229	} \
230	MACRO_END
231
232	/* scatter list macros */
233
234	#define SKIP_PORT_DESCRIPTORS(s, e) \
235	MACRO_BEGIN \
236	if ((s) != MACH_MSG_DESCRIPTOR_NULL) { \
237	while ((s) < (e)) { \
238	if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR) \
239	break; \
240	(s)++; \
241	} \
242	if ((s) >= (e)) \
243	(s) = MACH_MSG_DESCRIPTOR_NULL; \
244	} \
245	MACRO_END
246
247	#define INCREMENT_SCATTER(s) \
248	MACRO_BEGIN \
249	if ((s) != MACH_MSG_DESCRIPTOR_NULL) { \
250	(s)++; \
251	} \
252	MACRO_END
253
254	/*
255	* extern void
256	* ipc_kmsg_send_always(ipc_kmsg_t);
257	*
258	* Unfortunately, to avoid warnings/lint about unused variables
259	* when assertions are turned off, we need two versions of this.
260	*/
261	#if MACH_ASSERT
262
263	#define ipc_kmsg_send_always(kmsg) \
264	MACRO_BEGIN \
265	mach_msg_return_t mr; \
266	\
267	mr = ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS, \
268	MACH_MSG_TIMEOUT_NONE); \
269	assert(mr == MACH_MSG_SUCCESS); \
270	MACRO_END
271
272	#else /* MACH_ASSERT */
273
274	#define ipc_kmsg_send_always(kmsg) \
275	MACRO_BEGIN \
276	(void) ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS, \
277	MACH_MSG_TIMEOUT_NONE); \
278	MACRO_END
279
280	#endif /* MACH_ASSERT */
281
282	/* Allocate a kernel message */
283	extern ipc_kmsg_t ipc_kmsg_alloc(
284	mach_msg_size_t size);
285
286	/* Free a kernel message buffer */
287	extern void ipc_kmsg_free(
288	ipc_kmsg_t kmsg);
289
290	/* Destroy kernel message */
291	extern void ipc_kmsg_destroy(
292	ipc_kmsg_t kmsg);
293
294	/* Preallocate a kernel message buffer */
295	extern void ipc_kmsg_set_prealloc(
296	ipc_kmsg_t kmsg,
297	ipc_port_t port);
298
299	/* Clear a kernel message buffer */
300	extern void ipc_kmsg_clear_prealloc(
301	ipc_kmsg_t kmsg,
302	ipc_port_t port);
303
304	/* Allocate a kernel message buffer and copy a user message to the buffer */
305	extern mach_msg_return_t ipc_kmsg_get(
306	mach_msg_header_t *msg,
307	mach_msg_size_t size,
308	ipc_kmsg_t *kmsgp);
309
310	/* Allocate a kernel message buffer and copy a kernel message to the buffer */
311	extern mach_msg_return_t ipc_kmsg_get_from_kernel(
312	mach_msg_header_t *msg,
313	mach_msg_size_t size,
314	ipc_kmsg_t *kmsgp);
315
316	/* Send a message to a port */
317	extern mach_msg_return_t ipc_kmsg_send(
318	ipc_kmsg_t kmsg,
319	mach_msg_option_t option,
320	mach_msg_timeout_t timeout);
321
322	/* Copy a kernel message buffer to a user message */
323	extern mach_msg_return_t ipc_kmsg_put(
324	mach_msg_header_t *msg,
325	ipc_kmsg_t kmsg,
326	mach_msg_size_t size);
327
328	/* Copy a kernel message buffer to a kernel message */
329	extern void ipc_kmsg_put_to_kernel(
330	mach_msg_header_t *msg,
331	ipc_kmsg_t kmsg,
332	mach_msg_size_t size);
333
334	/* Copyin port rights in the header of a message */
335	extern mach_msg_return_t ipc_kmsg_copyin_header(
336	mach_msg_header_t *msg,
337	ipc_space_t space,
338	mach_port_name_t notify);
339
340	/* Copyin port rights and out-of-line memory from a user message */
341	extern mach_msg_return_t ipc_kmsg_copyin(
342	ipc_kmsg_t kmsg,
343	ipc_space_t space,
344	vm_map_t map,
345	mach_port_name_t notify);
346
347	/* Copyin port rights and out-of-line memory from a kernel message */
348	extern void ipc_kmsg_copyin_from_kernel(
349	ipc_kmsg_t kmsg);
350
351	/* Copyout port rights in the header of a message */
352	extern mach_msg_return_t ipc_kmsg_copyout_header(
353	mach_msg_header_t *msg,
354	ipc_space_t space,
355	mach_port_name_t notify);
356
357	/* Copyout a port right returning a name */
358	extern mach_msg_return_t ipc_kmsg_copyout_object(
359	ipc_space_t space,
360	ipc_object_t object,
361	mach_msg_type_name_t msgt_name,
362	mach_port_name_t *namep);
363
364	/* Copyout the header and body to a user message */
365	extern mach_msg_return_t ipc_kmsg_copyout(
366	ipc_kmsg_t kmsg,
367	ipc_space_t space,
368	vm_map_t map,
369	mach_port_name_t notify,
370	mach_msg_body_t *slist);
371
372	/* Copyout port rights and out-of-line memory from the body of a message */
373	extern mach_msg_return_t ipc_kmsg_copyout_body(
374	ipc_kmsg_t kmsg,
375	ipc_space_t space,
376	vm_map_t map,
377	mach_msg_body_t *slist);
378
379	/* Copyout port rights and out-of-line memory to a user message,
380	not reversing the ports in the header */
381	extern mach_msg_return_t ipc_kmsg_copyout_pseudo(
382	ipc_kmsg_t kmsg,
383	ipc_space_t space,
384	vm_map_t map,
385	mach_msg_body_t *slist);
386
387	/* Copyout the destination port in the message */
388	extern void ipc_kmsg_copyout_dest(
389	ipc_kmsg_t kmsg,
390	ipc_space_t space);
391
392	/* kernel's version of ipc_kmsg_copyout_dest */
393	extern void ipc_kmsg_copyout_to_kernel(
394	ipc_kmsg_t kmsg,
395	ipc_space_t space);
396
397	/* copyin a scatter list and check consistency */
398	extern mach_msg_body_t *ipc_kmsg_copyin_scatter(
399	mach_msg_header_t *msg,
400	mach_msg_size_t slist_size,
401	ipc_kmsg_t kmsg);
402
403	/* free a scatter list */
404	extern void ipc_kmsg_free_scatter(
405	mach_msg_body_t *slist,
406	mach_msg_size_t slist_size);
407
408	#include <mach_kdb.h>
409	#if MACH_KDB
410
411	/* Do a formatted dump of a kernel message */
412	extern void ipc_kmsg_print(
413	ipc_kmsg_t kmsg);
414
415	/* Do a formatted dump of a user message */
416	extern void ipc_msg_print(
417	mach_msg_header_t *msgh);
418
419	#endif /* MACH_KDB */
420
421	#endif /* _IPC_IPC_KMSG_H_ */