osfmk/ipc/ipc_kmsg.h

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
   7  *
   8  * This file contains Original Code and/or Modifications of Original Code
   9  * as defined in and that are subject to the Apple Public Source License
  10  * Version 2.0 (the 'License'). You may not use this file except in
  11  * compliance with the License. Please obtain a copy of the License at
  12  * http://www.opensource.apple.com/apsl/ and read it before using this
  13  * file.
  14  *
  15  * The Original Code and all software distributed under the License are
  16  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  17  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  18  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  20  * Please see the License for the specific language governing rights and
  21  * limitations under the License.
  22  *
  23  * @APPLE_LICENSE_HEADER_END@
  24  */
  25 /*
  26  * @OSF_COPYRIGHT@
  27  */
  28 /*
  29  * Mach Operating System
  30  * Copyright (c) 1991,1990,1989 Carnegie Mellon University
  31  * All Rights Reserved.
  32  *
  33  * Permission to use, copy, modify and distribute this software and its
  34  * documentation is hereby granted, provided that both the copyright
  35  * notice and this permission notice appear in all copies of the
  36  * software, derivative works or modified versions, and any portions
  37  * thereof, and that both notices appear in supporting documentation.
  38  *
  39  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  40  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  41  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  42  *
  43  * Carnegie Mellon requests users of this software to return to
  44  *
  45  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  46  *  School of Computer Science
  47  *  Carnegie Mellon University
  48  *  Pittsburgh PA 15213-3890
  49  *
  50  * any improvements or extensions that they make and grant Carnegie Mellon
  51  * the rights to redistribute these changes.
  52  */
  53 /*
  54  */
  55 /*
  56  *      File:   ipc/ipc_kmsg.h
  57  *      Author: Rich Draves
  58  *      Date:   1989
  59  *
  60  *      Definitions for kernel messages.
  61  */
  62
  63 #ifndef _IPC_IPC_KMSG_H_
  64 #define _IPC_IPC_KMSG_H_
  65
  66 #include <cpus.h>
  67
  68 #include <mach/vm_types.h>
  69 #include <mach/message.h>
  70 #include <kern/assert.h>
  71 #include <kern/cpu_number.h>
  72 #include <kern/macro_help.h>
  73 #include <kern/kalloc.h>
  74 #include <ipc/ipc_object.h>
  75
  76 /*
  77  *      This structure is only the header for a kmsg buffer;
  78  *      the actual buffer is normally larger.  The rest of the buffer
  79  *      holds the body of the message.
  80  *
  81  *      In a kmsg, the port fields hold pointers to ports instead
  82  *      of port names.  These pointers hold references.
  83  *
  84  *      The ikm_header.msgh_remote_port field is the destination
  85  *      of the message.
  86  */
  87
  88
  89 typedef struct ipc_kmsg {
  90         struct ipc_kmsg *ikm_next;
  91         struct ipc_kmsg *ikm_prev;
  92         ipc_port_t ikm_prealloc;        /* port we were preallocated from */
  93         mach_msg_size_t ikm_size;
  94         mach_msg_header_t ikm_header;
  95 } *ipc_kmsg_t;
  96
  97 #define IKM_NULL                ((ipc_kmsg_t) 0)
  98
  99 #define IKM_OVERHEAD                                                    \
 100                 (sizeof(struct ipc_kmsg) - sizeof(mach_msg_header_t))
 101
 102 #define ikm_plus_overhead(size) ((mach_msg_size_t)((size) + IKM_OVERHEAD))
 103 #define ikm_less_overhead(size) ((mach_msg_size_t)((size) - IKM_OVERHEAD))
 104
 105 /*
 106  * XXX  For debugging.
 107  */
 108 #define IKM_BOGUS               ((ipc_kmsg_t) 0xffffff10)
 109
 110 /*
 111  *      The size of the kernel message buffers that will be cached.
 112  *      IKM_SAVED_KMSG_SIZE includes overhead; IKM_SAVED_MSG_SIZE doesn't.
 113  */
 114
 115 #define IKM_SAVED_MSG_SIZE      ikm_less_overhead(256)
 116
 117 #define ikm_prealloc_inuse_port(kmsg)                                   \
 118         ((kmsg)->ikm_prealloc)
 119
 120 #define ikm_prealloc_inuse(kmsg)                                        \
 121         ((kmsg)->ikm_prealloc != IP_NULL)
 122
 123 #define ikm_prealloc_set_inuse(kmsg, port)                              \
 124 MACRO_BEGIN                                                             \
 125         assert((port) != IP_NULL);                                      \
 126         (kmsg)->ikm_prealloc = (port);                                  \
 127         ip_reference(port);                                             \
 128 MACRO_END
 129
 130 #define ikm_prealloc_clear_inuse(kmsg, port)                            \
 131 MACRO_BEGIN                                                             \
 132         (kmsg)->ikm_prealloc = IP_NULL;                                 \
 133         ip_release(port);                                               \
 134 MACRO_END
 135
 136
 137 #define ikm_init(kmsg, size)                                            \
 138 MACRO_BEGIN                                                             \
 139         (kmsg)->ikm_size = (size);                                      \
 140         (kmsg)->ikm_prealloc = IP_NULL;                                 \
 141         assert((kmsg)->ikm_prev = (kmsg)->ikm_next = IKM_BOGUS);        \
 142 MACRO_END
 143
 144 #define ikm_check_init(kmsg, size)                                      \
 145 MACRO_BEGIN                                                             \
 146         assert((kmsg)->ikm_size == (size));                             \
 147         assert((kmsg)->ikm_prev == IKM_BOGUS);                          \
 148         assert((kmsg)->ikm_next == IKM_BOGUS);                          \
 149 MACRO_END
 150
 151 struct ipc_kmsg_queue {
 152         struct ipc_kmsg *ikmq_base;
 153 };
 154
 155 typedef struct ipc_kmsg_queue *ipc_kmsg_queue_t;
 156
 157 #define IKMQ_NULL               ((ipc_kmsg_queue_t) 0)
 158
 159
 160 /*
 161  * Exported interfaces
 162  */
 163
 164 #define ipc_kmsg_queue_init(queue)              \
 165 MACRO_BEGIN                                     \
 166         (queue)->ikmq_base = IKM_NULL;          \
 167 MACRO_END
 168
 169 #define ipc_kmsg_queue_empty(queue)     ((queue)->ikmq_base == IKM_NULL)
 170
 171 /* Enqueue a kmsg */
 172 extern void ipc_kmsg_enqueue(
 173         ipc_kmsg_queue_t        queue,
 174         ipc_kmsg_t              kmsg);
 175
 176 /* Dequeue and return a kmsg */
 177 extern ipc_kmsg_t ipc_kmsg_dequeue(
 178         ipc_kmsg_queue_t        queue);
 179
 180 /* Pull a kmsg out of a queue */
 181 extern void ipc_kmsg_rmqueue(
 182         ipc_kmsg_queue_t        queue,
 183         ipc_kmsg_t              kmsg);
 184
 185 #define ipc_kmsg_queue_first(queue)             ((queue)->ikmq_base)
 186
 187 /* Return the kmsg following the given kmsg */
 188 extern ipc_kmsg_t ipc_kmsg_queue_next(
 189         ipc_kmsg_queue_t        queue,
 190         ipc_kmsg_t              kmsg);
 191
 192 #define ipc_kmsg_rmqueue_first_macro(queue, kmsg)                       \
 193 MACRO_BEGIN                                                             \
 194         register ipc_kmsg_t _next;                                      \
 195                                                                         \
 196         assert((queue)->ikmq_base == (kmsg));                           \
 197                                                                         \
 198         _next = (kmsg)->ikm_next;                                       \
 199         if (_next == (kmsg)) {                                          \
 200                 assert((kmsg)->ikm_prev == (kmsg));                     \
 201                 (queue)->ikmq_base = IKM_NULL;                          \
 202         } else {                                                        \
 203                 register ipc_kmsg_t _prev = (kmsg)->ikm_prev;           \
 204                                                                         \
 205                 (queue)->ikmq_base = _next;                             \
 206                 _next->ikm_prev = _prev;                                \
 207                 _prev->ikm_next = _next;                                \
 208         }                                                               \
 209         /* XXX Debug paranoia ASSIGNMENTS */                            \
 210         assert(kmsg->ikm_next = IKM_BOGUS);                             \
 211         assert(kmsg->ikm_prev = IKM_BOGUS);                             \
 212 MACRO_END
 213
 214 #define ipc_kmsg_enqueue_macro(queue, kmsg)                             \
 215 MACRO_BEGIN                                                             \
 216         register ipc_kmsg_t _first = (queue)->ikmq_base;                \
 217                                                                         \
 218         if (_first == IKM_NULL) {                                       \
 219                 (queue)->ikmq_base = (kmsg);                            \
 220                 (kmsg)->ikm_next = (kmsg);                              \
 221                 (kmsg)->ikm_prev = (kmsg);                              \
 222         } else {                                                        \
 223                 register ipc_kmsg_t _last = _first->ikm_prev;           \
 224                                                                         \
 225                 (kmsg)->ikm_next = _first;                              \
 226                 (kmsg)->ikm_prev = _last;                               \
 227                 _first->ikm_prev = (kmsg);                              \
 228                 _last->ikm_next = (kmsg);                               \
 229         }                                                               \
 230 MACRO_END
 231
 232 /* scatter list macros */
 233
 234 #define SKIP_PORT_DESCRIPTORS(s, e)                                     \
 235 MACRO_BEGIN                                                             \
 236         if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
 237                 while ((s) < (e)) {                                     \
 238                         if ((s)->type.type != MACH_MSG_PORT_DESCRIPTOR) \
 239                                 break;                                  \
 240                         (s)++;                                          \
 241                 }                                                       \
 242                 if ((s) >= (e))                                         \
 243                         (s) = MACH_MSG_DESCRIPTOR_NULL;                 \
 244         }                                                               \
 245 MACRO_END
 246
 247 #define INCREMENT_SCATTER(s)                                            \
 248 MACRO_BEGIN                                                             \
 249         if ((s) != MACH_MSG_DESCRIPTOR_NULL) {                          \
 250                 (s)++;                                                  \
 251         }                                                               \
 252 MACRO_END
 253
 254 /*
 255  *      extern void
 256  *      ipc_kmsg_send_always(ipc_kmsg_t);
 257  *
 258  *      Unfortunately, to avoid warnings/lint about unused variables
 259  *      when assertions are turned off, we need two versions of this.
 260  */
 261 #if     MACH_ASSERT
 262
 263 #define ipc_kmsg_send_always(kmsg)                                      \
 264 MACRO_BEGIN                                                             \
 265         mach_msg_return_t mr;                                           \
 266                                                                         \
 267         mr = ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS,                    \
 268                              MACH_MSG_TIMEOUT_NONE);                    \
 269         assert(mr == MACH_MSG_SUCCESS);                                 \
 270 MACRO_END
 271
 272 #else   /* MACH_ASSERT */
 273
 274 #define ipc_kmsg_send_always(kmsg)                                      \
 275 MACRO_BEGIN                                                             \
 276         (void) ipc_kmsg_send((kmsg), MACH_SEND_ALWAYS,                  \
 277                                MACH_MSG_TIMEOUT_NONE);                  \
 278 MACRO_END
 279
 280 #endif  /* MACH_ASSERT */
 281
 282 /* Allocate a kernel message */
 283 extern ipc_kmsg_t ipc_kmsg_alloc(
 284         mach_msg_size_t size);
 285
 286 /* Free a kernel message buffer */
 287 extern void ipc_kmsg_free(
 288         ipc_kmsg_t      kmsg);
 289
 290 /* Destroy kernel message */
 291 extern void ipc_kmsg_destroy(
 292         ipc_kmsg_t      kmsg);
 293
 294 /* Preallocate a kernel message buffer */
 295 extern void ipc_kmsg_set_prealloc(
 296         ipc_kmsg_t      kmsg,
 297         ipc_port_t      port);
 298
 299 /* Clear a kernel message buffer */
 300 extern void ipc_kmsg_clear_prealloc(
 301         ipc_kmsg_t      kmsg,
 302         ipc_port_t      port);
 303
 304 /* Allocate a kernel message buffer and copy a user message to the buffer */
 305 extern mach_msg_return_t ipc_kmsg_get(
 306         mach_msg_header_t       *msg,
 307         mach_msg_size_t         size,
 308         ipc_kmsg_t              *kmsgp);
 309
 310 /* Allocate a kernel message buffer and copy a kernel message to the buffer */
 311 extern mach_msg_return_t ipc_kmsg_get_from_kernel(
 312         mach_msg_header_t       *msg,
 313         mach_msg_size_t         size,
 314         ipc_kmsg_t              *kmsgp);
 315
 316 /* Send a message to a port */
 317 extern mach_msg_return_t ipc_kmsg_send(
 318         ipc_kmsg_t              kmsg,
 319         mach_msg_option_t       option,
 320         mach_msg_timeout_t      timeout);
 321
 322 /* Copy a kernel message buffer to a user message */
 323 extern mach_msg_return_t ipc_kmsg_put(
 324         mach_msg_header_t       *msg,
 325         ipc_kmsg_t              kmsg,
 326         mach_msg_size_t         size);
 327
 328 /* Copy a kernel message buffer to a kernel message */
 329 extern void ipc_kmsg_put_to_kernel(
 330         mach_msg_header_t       *msg,
 331         ipc_kmsg_t              kmsg,
 332         mach_msg_size_t         size);
 333
 334 /* Copyin port rights in the header of a message */
 335 extern mach_msg_return_t ipc_kmsg_copyin_header(
 336         mach_msg_header_t       *msg,
 337         ipc_space_t             space,
 338         mach_port_name_t        notify);
 339
 340 /* Copyin port rights and out-of-line memory from a user message */
 341 extern mach_msg_return_t ipc_kmsg_copyin(
 342         ipc_kmsg_t              kmsg,
 343         ipc_space_t             space,
 344         vm_map_t                map,
 345         mach_port_name_t        notify);
 346
 347 /* Copyin port rights and out-of-line memory from a kernel message */
 348 extern void ipc_kmsg_copyin_from_kernel(
 349         ipc_kmsg_t              kmsg);
 350
 351 /* Copyout port rights in the header of a message */
 352 extern mach_msg_return_t ipc_kmsg_copyout_header(
 353         mach_msg_header_t       *msg,
 354         ipc_space_t             space,
 355         mach_port_name_t        notify);
 356
 357 /* Copyout a port right returning a name */
 358 extern mach_msg_return_t ipc_kmsg_copyout_object(
 359         ipc_space_t             space,
 360         ipc_object_t            object,
 361         mach_msg_type_name_t    msgt_name,
 362         mach_port_name_t        *namep);
 363
 364 /* Copyout the header and body to a user message */
 365 extern mach_msg_return_t ipc_kmsg_copyout(
 366         ipc_kmsg_t              kmsg,
 367         ipc_space_t             space,
 368         vm_map_t                map,
 369         mach_port_name_t        notify,
 370         mach_msg_body_t         *slist);
 371
 372 /* Copyout port rights and out-of-line memory from the body of a message */
 373 extern mach_msg_return_t ipc_kmsg_copyout_body(
 374         ipc_kmsg_t              kmsg,
 375         ipc_space_t             space,
 376         vm_map_t                map,
 377         mach_msg_body_t         *slist);
 378
 379 /* Copyout port rights and out-of-line memory to a user message,
 380    not reversing the ports in the header */
 381 extern mach_msg_return_t ipc_kmsg_copyout_pseudo(
 382         ipc_kmsg_t              kmsg,
 383         ipc_space_t             space,
 384         vm_map_t                map,
 385         mach_msg_body_t         *slist);
 386
 387 /* Copyout the destination port in the message */
 388 extern void ipc_kmsg_copyout_dest(
 389         ipc_kmsg_t              kmsg,
 390         ipc_space_t             space);
 391
 392 /* kernel's version of ipc_kmsg_copyout_dest */
 393 extern void ipc_kmsg_copyout_to_kernel(
 394         ipc_kmsg_t              kmsg,
 395         ipc_space_t             space);
 396
 397 /* copyin a scatter list and check consistency */
 398 extern mach_msg_body_t *ipc_kmsg_copyin_scatter(
 399         mach_msg_header_t       *msg,
 400         mach_msg_size_t         slist_size,
 401         ipc_kmsg_t              kmsg);
 402
 403 /* free a scatter list */
 404 extern void ipc_kmsg_free_scatter(
 405         mach_msg_body_t         *slist,
 406         mach_msg_size_t         slist_size);
 407
 408 #include <mach_kdb.h>
 409 #if     MACH_KDB
 410
 411 /* Do a formatted dump of a kernel message */
 412 extern void ipc_kmsg_print(
 413         ipc_kmsg_t      kmsg);
 414
 415 /* Do a formatted dump of a user message */
 416 extern void ipc_msg_print(
 417         mach_msg_header_t       *msgh);
 418
 419 #endif  /* MACH_KDB */
 420
 421 #endif  /* _IPC_IPC_KMSG_H_ */