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

/*
 * 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_entry.h
 *	Author:	Rich Draves
 *	Date:	1989
 *
 *	Definitions for translation entries, which represent
 *	tasks' capabilities for ports and port sets.
 */

#ifndef	_IPC_IPC_ENTRY_H_
#define _IPC_IPC_ENTRY_H_

#include <mach/mach_types.h>
#include <mach/port.h>
#include <mach/kern_return.h>

#include <kern/kern_types.h>
#include <kern/zalloc.h>

#include <ipc/ipc_types.h>

/*
 *	Spaces hold capabilities for ipc_object_t's.
 *	Each ipc_entry_t records a capability.  Most capabilities have
 *	small names, and the entries are elements of a table.
 *	Capabilities can have large names, and a splay tree holds
 *	those entries.  The cutoff point between the table and the tree
 *	is adjusted dynamically to minimize memory consumption.
 *
 *	The ie_index field of entries in the table implements
 *	a ordered hash table with open addressing and linear probing.
 *	This hash table converts (space, object) -> name.
 *	It is used independently of the other fields.
 *
 *	Free (unallocated) entries in the table have null ie_object
 *	fields.  The ie_bits field is zero except for IE_BITS_GEN.
 *	The ie_next (ie_request) field links free entries into a free list.
 *
 *	The first entry in the table (index 0) is always free.
 *	It is used as the head of the free list.
 */

struct ipc_entry {
	struct ipc_object *ie_object;
	ipc_entry_bits_t ie_bits;
	union {
		mach_port_index_t next;		/* next in freelist, or...  */
		ipc_table_index_t request;	/* dead name request notify */
	} index;
	union {
		mach_port_index_t table;
		struct ipc_tree_entry *tree;
	} hash;
};

#define	ie_request	index.request
#define	ie_next		index.next
#define	ie_index	hash.table

#define	IE_BITS_UREFS_MASK	0x0000ffff	/* 16 bits of user-reference */
#define	IE_BITS_UREFS(bits)	((bits) & IE_BITS_UREFS_MASK)

#define	IE_BITS_TYPE_MASK	0x001f0000	/* 5 bits of capability type */
#define	IE_BITS_TYPE(bits)	((bits) & IE_BITS_TYPE_MASK)

#define	IE_BITS_COLLISION	0x00800000	/* 1 bit for collisions */


#ifndef NO_PORT_GEN
#define	IE_BITS_GEN_MASK	0xff000000	/* 8 bits for generation */
#define	IE_BITS_GEN(bits)	((bits) & IE_BITS_GEN_MASK)
#define	IE_BITS_GEN_ONE		0x04000000	/* low bit of generation */
#define IE_BITS_NEW_GEN(old)	(((old) + IE_BITS_GEN_ONE) & IE_BITS_GEN_MASK)
#else
#define	IE_BITS_GEN_MASK	0
#define	IE_BITS_GEN(bits)	0
#define	IE_BITS_GEN_ONE		0
#define IE_BITS_NEW_GEN(old)	(old)
#endif	/* !USE_PORT_GEN */


#define	IE_BITS_RIGHT_MASK	0x007fffff	/* relevant to the right */

struct ipc_tree_entry {
	struct ipc_entry ite_entry;
	mach_port_name_t ite_name;
	struct ipc_space *ite_space;
	struct ipc_tree_entry *ite_lchild;
	struct ipc_tree_entry *ite_rchild;
};

#define	ite_bits	ite_entry.ie_bits
#define	ite_object	ite_entry.ie_object
#define	ite_request	ite_entry.ie_request
#define	ite_next	ite_entry.hash.tree

extern zone_t ipc_tree_entry_zone;

#define ite_alloc()	((ipc_tree_entry_t) zalloc(ipc_tree_entry_zone))
#define	ite_free(ite)	zfree(ipc_tree_entry_zone, (ite))

/*
 * Exported interfaces
 */

/* Search for entry in a space by name */
extern ipc_entry_t ipc_entry_lookup(
	ipc_space_t		space,
	mach_port_name_t	name);

/* Allocate an entry in a space */
extern kern_return_t ipc_entry_get(
	ipc_space_t		space,
	mach_port_name_t	*namep,
	ipc_entry_t		*entryp);

/* Allocate an entry in a space, growing the space if necessary */
extern kern_return_t ipc_entry_alloc(
	ipc_space_t		space,
	mach_port_name_t	*namep,
	ipc_entry_t		*entryp);

/* Allocate/find an entry in a space with a specific name */
extern kern_return_t ipc_entry_alloc_name(
	ipc_space_t		space,
	mach_port_name_t	name,
	ipc_entry_t		*entryp);

/* Deallocate an entry from a space */
extern void ipc_entry_dealloc(
	ipc_space_t		space,
	mach_port_name_t	name,
	ipc_entry_t		entry);

/* Grow the table in a space */
extern kern_return_t ipc_entry_grow_table(
	ipc_space_t		space,
	ipc_table_elems_t	target_size);

#endif	/* _IPC_IPC_ENTRY_H_ */
Commit	Line	Data
1c79356b	1	/*
91447636	2	* Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
1c79356b	3	*
2d21ac55	4	* @APPLE_OSREFERENCE_LICENSE_HEADER_START@
8f6c56a5	5	*
2d21ac55 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.
8f6c56a5	14	*
2d21ac55 A	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
8f6c56a5 A	20	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
8f6c56a5 A	21	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
2d21ac55 A	22	* FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
	23	* Please see the License for the specific language governing rights and
	24	* limitations under the License.
8f6c56a5	25	*
2d21ac55	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_entry.h
	60	* Author: Rich Draves
	61	* Date: 1989
	62	*
	63	* Definitions for translation entries, which represent
	64	* tasks' capabilities for ports and port sets.
	65	*/
	66
	67	#ifndef _IPC_IPC_ENTRY_H_
	68	#define _IPC_IPC_ENTRY_H_
	69
91447636	70	#include <mach/mach_types.h>
1c79356b A	71	#include <mach/port.h>
1c79356b A	72	#include <mach/kern_return.h>
91447636 A	73
91447636 A	74	#include <kern/kern_types.h>
1c79356b	75	#include <kern/zalloc.h>
91447636	76
1c79356b A	77	#include <ipc/ipc_types.h>
	78
	79	/*
	80	* Spaces hold capabilities for ipc_object_t's.
	81	* Each ipc_entry_t records a capability. Most capabilities have
	82	* small names, and the entries are elements of a table.
	83	* Capabilities can have large names, and a splay tree holds
	84	* those entries. The cutoff point between the table and the tree
	85	* is adjusted dynamically to minimize memory consumption.
	86	*
	87	* The ie_index field of entries in the table implements
	88	* a ordered hash table with open addressing and linear probing.
	89	* This hash table converts (space, object) -> name.
	90	* It is used independently of the other fields.
	91	*
	92	* Free (unallocated) entries in the table have null ie_object
	93	* fields. The ie_bits field is zero except for IE_BITS_GEN.
	94	* The ie_next (ie_request) field links free entries into a free list.
	95	*
	96	* The first entry in the table (index 0) is always free.
	97	* It is used as the head of the free list.
	98	*/
	99
91447636	100	struct ipc_entry {
1c79356b A	101	struct ipc_object *ie_object;
	102	ipc_entry_bits_t ie_bits;
	103	union {
	104	mach_port_index_t next; /* next in freelist, or... */
	105	ipc_table_index_t request; /* dead name request notify */
	106	} index;
	107	union {
	108	mach_port_index_t table;
	109	struct ipc_tree_entry *tree;
	110	} hash;
91447636	111	};
1c79356b A	112
	113	#define ie_request index.request
	114	#define ie_next index.next
	115	#define ie_index hash.table
	116
	117	#define IE_BITS_UREFS_MASK 0x0000ffff /* 16 bits of user-reference */
	118	#define IE_BITS_UREFS(bits) ((bits) & IE_BITS_UREFS_MASK)
	119
	120	#define IE_BITS_TYPE_MASK 0x001f0000 /* 5 bits of capability type */
	121	#define IE_BITS_TYPE(bits) ((bits) & IE_BITS_TYPE_MASK)
	122
	123	#define IE_BITS_COLLISION 0x00800000 /* 1 bit for collisions */
	124
	125
	126	#ifndef NO_PORT_GEN
	127	#define IE_BITS_GEN_MASK 0xff000000 /* 8 bits for generation */
	128	#define IE_BITS_GEN(bits) ((bits) & IE_BITS_GEN_MASK)
	129	#define IE_BITS_GEN_ONE 0x04000000 /* low bit of generation */
	130	#define IE_BITS_NEW_GEN(old) (((old) + IE_BITS_GEN_ONE) & IE_BITS_GEN_MASK)
	131	#else
	132	#define IE_BITS_GEN_MASK 0
	133	#define IE_BITS_GEN(bits) 0
	134	#define IE_BITS_GEN_ONE 0
	135	#define IE_BITS_NEW_GEN(old) (old)
	136	#endif /* !USE_PORT_GEN */
	137
	138
	139	#define IE_BITS_RIGHT_MASK 0x007fffff /* relevant to the right */
	140
91447636	141	struct ipc_tree_entry {
1c79356b A	142	struct ipc_entry ite_entry;
	143	mach_port_name_t ite_name;
	144	struct ipc_space *ite_space;
	145	struct ipc_tree_entry *ite_lchild;
	146	struct ipc_tree_entry *ite_rchild;
91447636	147	};
1c79356b A	148
	149	#define ite_bits ite_entry.ie_bits
	150	#define ite_object ite_entry.ie_object
	151	#define ite_request ite_entry.ie_request
	152	#define ite_next ite_entry.hash.tree
	153
	154	extern zone_t ipc_tree_entry_zone;
	155
	156	#define ite_alloc() ((ipc_tree_entry_t) zalloc(ipc_tree_entry_zone))
91447636	157	#define ite_free(ite) zfree(ipc_tree_entry_zone, (ite))
1c79356b A	158
	159	/*
	160	* Exported interfaces
	161	*/
	162
	163	/* Search for entry in a space by name */
	164	extern ipc_entry_t ipc_entry_lookup(
	165	ipc_space_t space,
	166	mach_port_name_t name);
	167
	168	/* Allocate an entry in a space */
	169	extern kern_return_t ipc_entry_get(
	170	ipc_space_t space,
	171	mach_port_name_t *namep,
	172	ipc_entry_t *entryp);
	173
	174	/* Allocate an entry in a space, growing the space if necessary */
	175	extern kern_return_t ipc_entry_alloc(
	176	ipc_space_t space,
	177	mach_port_name_t *namep,
	178	ipc_entry_t *entryp);
	179
	180	/* Allocate/find an entry in a space with a specific name */
	181	extern kern_return_t ipc_entry_alloc_name(
	182	ipc_space_t space,
	183	mach_port_name_t name,
	184	ipc_entry_t *entryp);
	185
	186	/* Deallocate an entry from a space */
	187	extern void ipc_entry_dealloc(
	188	ipc_space_t space,
	189	mach_port_name_t name,
	190	ipc_entry_t entry);
	191
	192	/* Grow the table in a space */
	193	extern kern_return_t ipc_entry_grow_table(
91447636 A	194	ipc_space_t space,
91447636 A	195	ipc_table_elems_t target_size);
1c79356b A	196
1c79356b A	197	#endif /* _IPC_IPC_ENTRY_H_ */