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_table.c
60 * Author: Rich Draves
61 * Date: 1989
62 *
63 * Functions to manipulate tables of IPC capabilities.
64 */
65
66#include <mach/kern_return.h>
67#include <mach/vm_param.h>
68#include <ipc/ipc_table.h>
69#include <ipc/ipc_port.h>
70#include <ipc/ipc_entry.h>
71#include <kern/kalloc.h>
72#include <vm/vm_kern.h>
73
74ipc_table_size_t ipc_table_entries = NULL;
75unsigned int ipc_table_entries_size = CONFIG_IPC_TABLE_ENTRIES_STEPS;
76
77ipc_table_size_t ipc_table_requests;
78unsigned int ipc_table_requests_size = 64;
79
80static void
81ipc_table_fill(
82 ipc_table_size_t its, /* array to fill */
83 unsigned int num, /* size of array */
84 unsigned int min, /* at least this many elements */
85 vm_size_t elemsize) /* size of elements */
86{
87 unsigned int index;
88 vm_size_t minsize = min * elemsize;
89 vm_size_t size;
90 vm_size_t incrsize;
91
92 /* first use powers of two, up to the page size */
93
94 for (index = 0, size = 1;
95 (index < num) && (size < PAGE_MAX_SIZE);
96 size <<= 1) {
97 if (size >= minsize) {
98 its[index].its_size = (ipc_table_elems_t)(size / elemsize);
99 index++;
100 }
101 }
102
103 /* then increments of a page, then two pages, etc. */
104
105 for (incrsize = PAGE_MAX_SIZE; index < num;) {
106 unsigned int period;
107
108 for (period = 0;
109 (period < 15) && (index < num);
110 period++, size += incrsize) {
111 if (size >= minsize) {
112 its[index].its_size = (ipc_table_elems_t)(size / elemsize);
113 index++;
114 }
115 }
116 if (incrsize < (vm_size_t)(PAGE_MAX_SIZE << 3))
117 incrsize <<= 1;
118 }
119}
120
121void
122ipc_table_init(void)
123{
124 ipc_table_entries = (ipc_table_size_t)
125 kalloc(sizeof(struct ipc_table_size) *
126 ipc_table_entries_size);
127 assert(ipc_table_entries != ITS_NULL);
128
129 ipc_table_fill(ipc_table_entries, ipc_table_entries_size - 1,
130 16, sizeof(struct ipc_entry));
131
132 /* the last two elements should have the same size */
133
134 ipc_table_entries[ipc_table_entries_size - 1].its_size =
135 ipc_table_entries[ipc_table_entries_size - 2].its_size;
136
137
138 ipc_table_requests = (ipc_table_size_t)
139 kalloc(sizeof(struct ipc_table_size) *
140 ipc_table_requests_size);
141 assert(ipc_table_requests != ITS_NULL);
142
143 ipc_table_fill(ipc_table_requests, ipc_table_requests_size - 1,
144 2, sizeof(struct ipc_port_request));
145
146 /* the last element should have zero size */
147
148 ipc_table_requests[ipc_table_requests_size - 1].its_size = 0;
149}
150
151
152/*
153 * Routine: ipc_table_max_entries
154 * Purpose:
155 * returns the maximum number of entries an IPC space
156 * is allowed to contain (the maximum size to which it will grow)
157 * Conditions:
158 * none
159 */
160unsigned int
161ipc_table_max_entries(void)
162{
163 if (!ipc_table_entries || ipc_table_entries_size < 2)
164 return 0;
165 return (unsigned int)ipc_table_entries[ipc_table_entries_size - 1].its_size;
166}
167
168
169/*
170 * Routine: ipc_table_max_requests
171 * Purpose:
172 * returns the maximum number of requests an IPC request table
173 * is allowed to contain (the maximum size to which it will grow)
174 * Conditions:
175 * none
176 */
177unsigned int
178ipc_table_max_requests(void)
179{
180 if (!ipc_table_requests || ipc_table_requests_size < 2)
181 return 0;
182 return (unsigned int)ipc_table_requests[ipc_table_requests_size - 2].its_size;
183}
184
185
186/*
187 * Routine: ipc_table_alloc
188 * Purpose:
189 * Allocate a table.
190 * Conditions:
191 * May block.
192 */
193
194void *
195ipc_table_alloc(
196 vm_size_t size)
197{
198 return kalloc(size);
199}
200
201
202/*
203 * Routine: ipc_table_free
204 * Purpose:
205 * Free a table allocated with ipc_table_alloc.
206 * Conditions:
207 * May block.
208 */
209
210void
211ipc_table_free(
212 vm_size_t size,
213 void * table)
214{
215 kfree(table, size);
216}
217