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

/*
 * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * The contents of this file constitute Original Code as defined in and
 * are subject to the Apple Public Source License Version 1.1 (the
 * "License").  You may not use this file except in compliance with the
 * License.  Please obtain a copy of the License at
 * http://www.apple.com/publicsource and read it before using this file.
 * 
 * This 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 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_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/port.h>
#include <mach/kern_return.h>
#include <kern/zalloc.h>
#include <ipc/port.h>
#include <ipc/ipc_table.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.
 */

typedef natural_t ipc_entry_bits_t;
typedef ipc_table_elems_t ipc_entry_num_t;	/* number of entries */

typedef 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;
} *ipc_entry_t;

#define	IE_NULL		((ipc_entry_t) 0)

#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 */

typedef 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;
} *ipc_tree_entry_t;

#define	ITE_NULL	((ipc_tree_entry_t) 0)

#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, (vm_offset_t) (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,
	int		target_size);

#endif	/* _IPC_IPC_ENTRY_H_ */
Commit	Line	Data
1c79356b A	1	/*
	2	* Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
	3	*
	4	* @APPLE_LICENSE_HEADER_START@
	5	*
de355530 A	6	* The contents of this file constitute Original Code as defined in and
	7	* are subject to the Apple Public Source License Version 1.1 (the
	8	* "License"). You may not use this file except in compliance with the
	9	* License. Please obtain a copy of the License at
	10	* http://www.apple.com/publicsource and read it before using this file.
1c79356b	11	*
de355530 A	12	* This Original Code and all software distributed under the License are
de355530 A	13	* distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
1c79356b A	14	* EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
1c79356b A	15	* INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
de355530 A	16	* FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the
	17	* License for the specific language governing rights and limitations
	18	* under the License.
1c79356b A	19	*
	20	* @APPLE_LICENSE_HEADER_END@
	21	*/
	22	/*
	23	* @OSF_COPYRIGHT@
	24	*/
	25	/*
	26	* Mach Operating System
	27	* Copyright (c) 1991,1990,1989 Carnegie Mellon University
	28	* All Rights Reserved.
	29	*
	30	* Permission to use, copy, modify and distribute this software and its
	31	* documentation is hereby granted, provided that both the copyright
	32	* notice and this permission notice appear in all copies of the
	33	* software, derivative works or modified versions, and any portions
	34	* thereof, and that both notices appear in supporting documentation.
	35	*
	36	* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
	37	* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
	38	* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
	39	*
	40	* Carnegie Mellon requests users of this software to return to
	41	*
	42	* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
	43	* School of Computer Science
	44	* Carnegie Mellon University
	45	* Pittsburgh PA 15213-3890
	46	*
	47	* any improvements or extensions that they make and grant Carnegie Mellon
	48	* the rights to redistribute these changes.
	49	*/
	50	/*
	51	*/
	52	/*
	53	* File: ipc/ipc_entry.h
	54	* Author: Rich Draves
	55	* Date: 1989
	56	*
	57	* Definitions for translation entries, which represent
	58	* tasks' capabilities for ports and port sets.
	59	*/
	60
	61	#ifndef _IPC_IPC_ENTRY_H_
	62	#define _IPC_IPC_ENTRY_H_
	63
	64	#include <mach/port.h>
	65	#include <mach/kern_return.h>
	66	#include <kern/zalloc.h>
	67	#include <ipc/port.h>
	68	#include <ipc/ipc_table.h>
	69	#include <ipc/ipc_types.h>
	70
	71	/*
	72	* Spaces hold capabilities for ipc_object_t's.
	73	* Each ipc_entry_t records a capability. Most capabilities have
	74	* small names, and the entries are elements of a table.
	75	* Capabilities can have large names, and a splay tree holds
	76	* those entries. The cutoff point between the table and the tree
	77	* is adjusted dynamically to minimize memory consumption.
	78	*
	79	* The ie_index field of entries in the table implements
	80	* a ordered hash table with open addressing and linear probing.
	81	* This hash table converts (space, object) -> name.
	82	* It is used independently of the other fields.
83	*
84	* Free (unallocated) entries in the table have null ie_object
85	* fields. The ie_bits field is zero except for IE_BITS_GEN.
86	* The ie_next (ie_request) field links free entries into a free list.
87	*
88	* The first entry in the table (index 0) is always free.
89	* It is used as the head of the free list.
90	*/
91
92	typedef natural_t ipc_entry_bits_t;
93	typedef ipc_table_elems_t ipc_entry_num_t; /* number of entries */
94
95	typedef struct ipc_entry {
96	struct ipc_object *ie_object;
97	ipc_entry_bits_t ie_bits;
98	union {
99	mach_port_index_t next; /* next in freelist, or... */
100	ipc_table_index_t request; /* dead name request notify */
101	} index;
102	union {
103	mach_port_index_t table;
104	struct ipc_tree_entry *tree;
105	} hash;
106	} *ipc_entry_t;
107
108	#define IE_NULL ((ipc_entry_t) 0)
109
110	#define ie_request index.request
111	#define ie_next index.next
112	#define ie_index hash.table
113
114	#define IE_BITS_UREFS_MASK 0x0000ffff /* 16 bits of user-reference */
115	#define IE_BITS_UREFS(bits) ((bits) & IE_BITS_UREFS_MASK)
116
117	#define IE_BITS_TYPE_MASK 0x001f0000 /* 5 bits of capability type */
118	#define IE_BITS_TYPE(bits) ((bits) & IE_BITS_TYPE_MASK)
119
120	#define IE_BITS_COLLISION 0x00800000 /* 1 bit for collisions */
121
122
123	#ifndef NO_PORT_GEN
124	#define IE_BITS_GEN_MASK 0xff000000 /* 8 bits for generation */
125	#define IE_BITS_GEN(bits) ((bits) & IE_BITS_GEN_MASK)
126	#define IE_BITS_GEN_ONE 0x04000000 /* low bit of generation */
127	#define IE_BITS_NEW_GEN(old) (((old) + IE_BITS_GEN_ONE) & IE_BITS_GEN_MASK)
128	#else
129	#define IE_BITS_GEN_MASK 0
130	#define IE_BITS_GEN(bits) 0
131	#define IE_BITS_GEN_ONE 0
132	#define IE_BITS_NEW_GEN(old) (old)
133	#endif /* !USE_PORT_GEN */
134
135
136	#define IE_BITS_RIGHT_MASK 0x007fffff /* relevant to the right */
137
138	typedef struct ipc_tree_entry {
139	struct ipc_entry ite_entry;
140	mach_port_name_t ite_name;
141	struct ipc_space *ite_space;
142	struct ipc_tree_entry *ite_lchild;
143	struct ipc_tree_entry *ite_rchild;
144	} *ipc_tree_entry_t;
145
146	#define ITE_NULL ((ipc_tree_entry_t) 0)
147
148	#define ite_bits ite_entry.ie_bits
149	#define ite_object ite_entry.ie_object
150	#define ite_request ite_entry.ie_request
151	#define ite_next ite_entry.hash.tree
152
153	extern zone_t ipc_tree_entry_zone;
154
155	#define ite_alloc() ((ipc_tree_entry_t) zalloc(ipc_tree_entry_zone))
156	#define ite_free(ite) zfree(ipc_tree_entry_zone, (vm_offset_t) (ite))
157
158	/*
159	* Exported interfaces
160	*/
161
162	/* Search for entry in a space by name */
163	extern ipc_entry_t ipc_entry_lookup(
164	ipc_space_t space,
165	mach_port_name_t name);
166
167	/* Allocate an entry in a space */
168	extern kern_return_t ipc_entry_get(
169	ipc_space_t space,
170	mach_port_name_t *namep,
171	ipc_entry_t *entryp);
172
173	/* Allocate an entry in a space, growing the space if necessary */
174	extern kern_return_t ipc_entry_alloc(
175	ipc_space_t space,
176	mach_port_name_t *namep,
177	ipc_entry_t *entryp);
178
179	/* Allocate/find an entry in a space with a specific name */
180	extern kern_return_t ipc_entry_alloc_name(
181	ipc_space_t space,
182	mach_port_name_t name,
183	ipc_entry_t *entryp);
184
185	/* Deallocate an entry from a space */
186	extern void ipc_entry_dealloc(
187	ipc_space_t space,
188	mach_port_name_t name,
189	ipc_entry_t entry);
190
191	/* Grow the table in a space */
192	extern kern_return_t ipc_entry_grow_table(
193	ipc_space_t space,
194	int target_size);
195
196	#endif /* _IPC_IPC_ENTRY_H_ */