osfmk/ipc/ipc_space.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   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.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  17  * License for the specific language governing rights and limitations
  18  * under the License.
  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_space.c
  54  *      Author: Rich Draves
  55  *      Date:   1989
  56  *
  57  *      Functions to manipulate IPC capability spaces.
  58  */
  59
  60 #include <mach_kdb.h>
  61
  62 #include <mach/boolean.h>
  63 #include <mach/kern_return.h>
  64 #include <mach/port.h>
  65 #include <kern/assert.h>
  66 #include <kern/sched_prim.h>
  67 #include <kern/zalloc.h>
  68 #include <ipc/port.h>
  69 #include <ipc/ipc_entry.h>
  70 #include <ipc/ipc_splay.h>
  71 #include <ipc/ipc_object.h>
  72 #include <ipc/ipc_hash.h>
  73 #include <ipc/ipc_table.h>
  74 #include <ipc/ipc_port.h>
  75 #include <ipc/ipc_space.h>
  76 #include <ipc/ipc_right.h>
  77 #include <string.h>
  78
  79 zone_t ipc_space_zone;
  80 ipc_space_t ipc_space_kernel;
  81 ipc_space_t ipc_space_reply;
  82 #if     MACH_KDB
  83 ipc_space_t default_pager_space;
  84 #endif  /* MACH_KDB */
  85
  86 /*
  87  *      Routine:        ipc_space_reference
  88  *      Routine:        ipc_space_release
  89  *      Purpose:
  90  *              Function versions of the IPC space macros.
  91  *              The "is_" cover macros can be defined to use the
  92  *              macros or the functions, as desired.
  93  */
  94
  95 void
  96 ipc_space_reference(
  97         ipc_space_t     space)
  98 {
  99         ipc_space_reference_macro(space);
 100 }
 101
 102 void
 103 ipc_space_release(
 104         ipc_space_t     space)
 105 {
 106         ipc_space_release_macro(space);
 107 }
 108
 109 /*
 110  *      Routine:        ipc_space_create
 111  *      Purpose:
 112  *              Creates a new IPC space.
 113  *
 114  *              The new space has two references, one for the caller
 115  *              and one because it is active.
 116  *      Conditions:
 117  *              Nothing locked.  Allocates memory.
 118  *      Returns:
 119  *              KERN_SUCCESS            Created a space.
 120  *              KERN_RESOURCE_SHORTAGE  Couldn't allocate memory.
 121  */
 122
 123 kern_return_t
 124 ipc_space_create(
 125         ipc_table_size_t        initial,
 126         ipc_space_t             *spacep)
 127 {
 128         ipc_space_t space;
 129         ipc_entry_t table;
 130         ipc_entry_num_t new_size;
 131         mach_port_index_t index;
 132
 133         space = is_alloc();
 134         if (space == IS_NULL)
 135                 return KERN_RESOURCE_SHORTAGE;
 136
 137         table = it_entries_alloc(initial);
 138         if (table == IE_NULL) {
 139                 is_free(space);
 140                 return KERN_RESOURCE_SHORTAGE;
 141         }
 142
 143         new_size = initial->its_size;
 144         memset((void *) table, 0, new_size * sizeof(struct ipc_entry));
 145
 146         /*
 147          *      Initialize the free list in the table.
 148          *      Add the entries in reverse order, and
 149          *      set the generation number to -1, so that
 150          *      initial allocations produce "natural" names.
 151          */
 152         for (index = 0; index < new_size; index++) {
 153                 ipc_entry_t entry = &table[index];
 154
 155                 entry->ie_bits = IE_BITS_GEN_MASK;
 156                 entry->ie_next = index+1;
 157         }
 158         table[new_size-1].ie_next = 0;
 159
 160         is_ref_lock_init(space);
 161         space->is_references = 2;
 162
 163         is_lock_init(space);
 164         space->is_active = TRUE;
 165         space->is_growing = FALSE;
 166         space->is_table = table;
 167         space->is_table_size = new_size;
 168         space->is_table_next = initial+1;
 169
 170         ipc_splay_tree_init(&space->is_tree);
 171         space->is_tree_total = 0;
 172         space->is_tree_small = 0;
 173         space->is_tree_hash = 0;
 174
 175         *spacep = space;
 176         return KERN_SUCCESS;
 177 }
 178
 179 /*
 180  *      Routine:        ipc_space_create_special
 181  *      Purpose:
 182  *              Create a special space.  A special space
 183  *              doesn't hold rights in the normal way.
 184  *              Instead it is place-holder for holding
 185  *              disembodied (naked) receive rights.
 186  *              See ipc_port_alloc_special/ipc_port_dealloc_special.
 187  *      Conditions:
 188  *              Nothing locked.
 189  *      Returns:
 190  *              KERN_SUCCESS            Created a space.
 191  *              KERN_RESOURCE_SHORTAGE  Couldn't allocate memory.
 192  */
 193
 194 kern_return_t
 195 ipc_space_create_special(
 196         ipc_space_t     *spacep)
 197 {
 198         ipc_space_t space;
 199
 200         space = is_alloc();
 201         if (space == IS_NULL)
 202                 return KERN_RESOURCE_SHORTAGE;
 203
 204         is_ref_lock_init(space);
 205         space->is_references = 1;
 206
 207         is_lock_init(space);
 208         space->is_active = FALSE;
 209
 210         *spacep = space;
 211         return KERN_SUCCESS;
 212 }
 213
 214 /*
 215  * ipc_space_clean - remove all port references from an ipc space.
 216  *
 217  * In order to follow the traditional semantic, ipc_space_destroy
 218  * will not destroy the entire port table of a shared space.  Instead
 219  * it will simply clear its own sub-space.
 220  */
 221 void
 222 ipc_space_clean(
 223         ipc_space_t space)
 224 {
 225         ipc_tree_entry_t tentry;
 226         ipc_entry_t table;
 227         ipc_entry_num_t size;
 228         mach_port_index_t index;
 229
 230         /*
 231          *      If somebody is trying to grow the table,
 232          *      we must wait until they finish and figure
 233          *      out the space died.
 234          */
 235         is_write_lock(space);
 236         while (space->is_growing) {
 237                 assert_wait((event_t) space, THREAD_UNINT);
 238                 is_write_unlock(space);
 239                 thread_block((void (*)(void)) 0);
 240                 is_write_lock(space);
 241         }
 242
 243         /*
 244          *      Now we can futz with it since we have the write lock.
 245          */
 246 #if     MACH_KDB
 247         if (space == default_pager_space)
 248                 default_pager_space = IS_NULL;
 249 #endif  /* MACH_KDB */
 250
 251         table = space->is_table;
 252         size = space->is_table_size;
 253
 254         for (index = 0; index < size; index++) {
 255                 ipc_entry_t entry = &table[index];
 256                 mach_port_type_t type;
 257
 258                 type = IE_BITS_TYPE(entry->ie_bits);
 259                 if (type != MACH_PORT_TYPE_NONE) {
 260                         mach_port_name_t name = MACH_PORT_MAKE(index,
 261                                                 IE_BITS_GEN(entry->ie_bits));
 262                         ipc_right_destroy(space, name, entry);
 263                 }
 264         }
 265
 266         /*
 267          * JMM - Now the table is cleaned out.  We don't bother shrinking the
 268          * size of the table at this point, but we probably should if it is
 269          * really large.  Lets just clean up the splay tree.
 270          */
 271  start_splay:
 272         for (tentry = ipc_splay_traverse_start(&space->is_tree);
 273              tentry != ITE_NULL;
 274              tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
 275                 int i;
 276                 mach_port_type_t type;
 277                 mach_port_name_t name = tentry->ite_name;
 278
 279                 type = IE_BITS_TYPE(tentry->ite_bits);
 280                 /*
 281                  * If it is a real right, then destroy it.  This will have the
 282                  * side effect of removing it from the splay, so start over.
 283                  */
 284                 if(type != MACH_PORT_TYPE_NONE) {
 285                         ipc_splay_traverse_finish(&space->is_tree);
 286                         ipc_right_destroy(space, name, &tentry->ite_entry);
 287                         goto start_splay;
 288                 }
 289         }
 290         ipc_splay_traverse_finish(&space->is_tree);
 291         is_write_unlock(space);
 292 }
 293
 294
 295 /*
 296  *      Routine:        ipc_space_destroy
 297  *      Purpose:
 298  *              Marks the space as dead and cleans up the entries.
 299  *              Does nothing if the space is already dead.
 300  *      Conditions:
 301  *              Nothing locked.
 302  */
 303
 304 void
 305 ipc_space_destroy(
 306         ipc_space_t     space)
 307 {
 308         boolean_t active;
 309         ipc_tree_entry_t tentry;
 310         ipc_entry_t table;
 311         ipc_entry_num_t size;
 312         mach_port_index_t index;
 313
 314         assert(space != IS_NULL);
 315
 316         is_write_lock(space);
 317         active = space->is_active;
 318         space->is_active = FALSE;
 319         is_write_unlock(space);
 320
 321         if (!active)
 322                 return;
 323
 324
 325         /*
 326          *      If somebody is trying to grow the table,
 327          *      we must wait until they finish and figure
 328          *      out the space died.
 329          */
 330         is_read_lock(space);
 331         while (space->is_growing) {
 332                 assert_wait((event_t) space, THREAD_UNINT);
 333                 is_read_unlock(space);
 334                 thread_block((void (*)(void)) 0);
 335                 is_read_lock(space);
 336         }
 337
 338         is_read_unlock(space);
 339         /*
 340          *      Now we can futz with it unlocked.
 341          */
 342 #if     MACH_KDB
 343         if (space == default_pager_space)
 344                 default_pager_space = IS_NULL;
 345 #endif  /* MACH_KDB */
 346
 347         table = space->is_table;
 348         size = space->is_table_size;
 349
 350         for (index = 0; index < size; index++) {
 351                 ipc_entry_t entry = &table[index];
 352                 mach_port_type_t type;
 353
 354                 type = IE_BITS_TYPE(entry->ie_bits);
 355                 if (type != MACH_PORT_TYPE_NONE) {
 356                         mach_port_name_t name;
 357
 358                         name = MACH_PORT_MAKE(index,
 359                                               IE_BITS_GEN(entry->ie_bits));
 360                         ipc_right_clean(space, name, entry);
 361                 }
 362         }
 363
 364         it_entries_free(space->is_table_next-1, table);
 365         space->is_table_size = 0;
 366
 367         for (tentry = ipc_splay_traverse_start(&space->is_tree);
 368              tentry != ITE_NULL;
 369              tentry = ipc_splay_traverse_next(&space->is_tree, TRUE)) {
 370                 mach_port_type_t type;
 371                 mach_port_name_t name = tentry->ite_name;
 372
 373                 type = IE_BITS_TYPE(tentry->ite_bits);
 374                 assert(type != MACH_PORT_TYPE_NONE);
 375
 376                 ipc_right_clean(space, name, &tentry->ite_entry);
 377
 378                 if(type == MACH_PORT_TYPE_SEND)
 379                         ipc_hash_global_delete(space, tentry->ite_object,
 380                                                name, tentry);
 381         }
 382         ipc_splay_traverse_finish(&space->is_tree);
 383
 384         /*
 385          *      Because the space is now dead,
 386          *      we must release the "active" reference for it.
 387          *      Our caller still has his reference.
 388          */
 389         is_release(space);
 390 }