1/* 2 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 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 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 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 70#include <mach/mach_types.h> 71#include <mach/port.h> 72#include <mach/kern_return.h> 73 74#include <kern/kern_types.h> 75#include <kern/zalloc.h> 76 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 100struct ipc_entry { 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; 111}; 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 141struct ipc_tree_entry { 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; 147}; 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 154extern zone_t ipc_tree_entry_zone; 155 156#define ite_alloc() ((ipc_tree_entry_t) zalloc(ipc_tree_entry_zone)) 157#define ite_free(ite) zfree(ipc_tree_entry_zone, (ite)) 158 159/* 160 * Exported interfaces 161 */ 162 163/* Search for entry in a space by name */ 164extern 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 */ 169extern 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 */ 175extern 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 */ 181extern 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 */ 187extern 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 */ 193extern kern_return_t ipc_entry_grow_table( 194 ipc_space_t space, 195 ipc_table_elems_t target_size); 196 197#endif /* _IPC_IPC_ENTRY_H_ */ 198