osfmk/ipc/ipc_object.h

   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
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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_object.h
  54  *      Author: Rich Draves
  55  *      Date:   1989
  56  *
  57  *      Definitions for IPC objects, for which tasks have capabilities.
  58  */
  59
  60 #ifndef _IPC_IPC_OBJECT_H_
  61 #define _IPC_IPC_OBJECT_H_
  62
  63 #include <mach_rt.h>
  64 #include <cpus.h>
  65 #include <mach_kdb.h>
  66
  67 #include <mach/kern_return.h>
  68 #include <mach/message.h>
  69 #include <kern/lock.h>
  70 #include <kern/macro_help.h>
  71 #include <kern/thread_pool.h>
  72 #include <kern/zalloc.h>
  73 #include <ipc/ipc_types.h>
  74
  75 typedef natural_t ipc_object_refs_t;    /* for ipc/ipc_object.h         */
  76 typedef natural_t ipc_object_bits_t;
  77 typedef natural_t ipc_object_type_t;
  78
  79 /*
  80  * There is no lock in the ipc_object; it is in the enclosing kernel
  81  * data structure (rpc_common_data) used by both ipc_port and ipc_pset.
  82  * The ipc_object is used to both tag and reference count these two data
  83  * structures, and (Noto Bene!) pointers to either of these or the
  84  * ipc_object at the head of these are freely cast back and forth; hence
  85  * the ipc_object MUST BE FIRST in the ipc_common_data.
  86  *
  87  * If the RPC implementation enabled user-mode code to use kernel-level
  88  * data structures (as ours used to), this peculiar structuring would
  89  * avoid having anything in user code depend on the kernel configuration
  90  * (with which lock size varies).
  91  */
  92 struct ipc_object {
  93         ipc_object_refs_t io_references;
  94         ipc_object_bits_t io_bits;
  95         port_name_t       io_receiver_name;
  96         struct thread_pool      io_thread_pool;
  97 #if NCPUS == 1
  98         usimple_lock_data_t     io_lock_data;
  99 #else
 100         decl_mutex_data(,       io_lock_data)
 101 #endif
 102 };
 103
 104 /*
 105  * Legacy defines.  Should use IPC_OBJECT_NULL, etc...
 106  */
 107 #define IO_NULL                 ((ipc_object_t) 0)
 108 #define IO_DEAD                 ((ipc_object_t) -1)
 109 #define IO_VALID(io)            (((io) != IO_NULL) && ((io) != IO_DEAD))
 110
 111 /*
 112  *      IPC steals the high-order bits from the kotype to use
 113  *      for its own purposes.  This allows IPC to record facts
 114  *      about ports that aren't otherwise obvious from the
 115  *      existing port fields.  In particular, IPC can optionally
 116  *      mark a port for no more senders detection.  Any change
 117  *      to IO_BITS_PORT_INFO must be coordinated with bitfield
 118  *      definitions in ipc_port.h.
 119  */
 120 #define IO_BITS_PORT_INFO       0x0000f000      /* stupid port tricks */
 121 #define IO_BITS_KOTYPE          0x00000fff      /* used by the object */
 122 #define IO_BITS_OTYPE           0x7fff0000      /* determines a zone */
 123 #define IO_BITS_ACTIVE          0x80000000      /* is object alive? */
 124
 125 #define io_active(io)           ((io)->io_bits & IO_BITS_ACTIVE)
 126
 127 #define io_otype(io)            (((io)->io_bits & IO_BITS_OTYPE) >> 16)
 128 #define io_kotype(io)           ((io)->io_bits & IO_BITS_KOTYPE)
 129
 130 #define io_makebits(active, otype, kotype)      \
 131         (((active) ? IO_BITS_ACTIVE : 0) | ((otype) << 16) | (kotype))
 132
 133 /*
 134  * Object types: ports, port sets, kernel-loaded ports
 135  */
 136 #define IOT_PORT                0
 137 #define IOT_PORT_SET            1
 138 #define IOT_NUMBER              2               /* number of types used */
 139
 140 extern zone_t ipc_object_zones[IOT_NUMBER];
 141
 142 #define io_alloc(otype)         \
 143                 ((ipc_object_t) zalloc(ipc_object_zones[(otype)]))
 144
 145 #if     MACH_ASSERT
 146 /*
 147  *      Call the routine for io_free so that checking can be performed.
 148  */
 149 extern void     io_free(
 150                         unsigned int    otype,
 151                         ipc_object_t    object);
 152
 153 #else   /* MACH_ASSERT */
 154 #define io_free(otype, io)      \
 155                 zfree(ipc_object_zones[(otype)], (vm_offset_t) (io))
 156 #endif  /* MACH_ASSERT */
 157
 158 /*
 159  * Here we depend on the ipc_object being first within the ipc_common_data,
 160  * which is first within the rpc_common_data, which in turn must be first
 161  * within any kernel data structure needing to lock an ipc_object
 162  * (ipc_port and ipc_pset).
 163  */
 164 #if     NCPUS == 1
 165
 166 #define io_lock_init(io) \
 167         usimple_lock_init(&(io)-io_lock_data, ETAP_IPC_OBJECT)
 168 #define io_lock(io) \
 169         usimple_lock(&(io)->io_lock_data)
 170 #define io_lock_try(io) \
 171         usimple_lock_try(&(io)->io_lock_data)
 172 #define io_unlock(io) \
 173         usimple_unlock(&(io)->io_lock_data)
 174
 175 #else   /* NCPUS == 1 */
 176
 177 #define io_lock_init(io) \
 178         mutex_init(&(io)->io_lock_data, ETAP_IPC_OBJECT)
 179 #define io_lock(io) \
 180         mutex_lock(&(io)->io_lock_data)
 181 #define io_lock_try(io) \
 182         mutex_try(&(io)->io_lock_data)
 183 #define io_unlock(io) \
 184         mutex_unlock(&(io)->io_lock_data)
 185
 186 #endif  /* NCPUS == 1 */
 187
 188 #if     NCPUS > 1
 189 #define _VOLATILE_ volatile
 190 #else   /* NCPUS > 1 */
 191 #define _VOLATILE_
 192 #endif  /* NCPUS > 1 */
 193
 194 #define io_check_unlock(io)                                             \
 195 MACRO_BEGIN                                                             \
 196         _VOLATILE_ ipc_object_refs_t _refs = (io)->io_references;       \
 197                                                                         \
 198         io_unlock(io);                                                  \
 199         if (_refs == 0)                                                 \
 200                 io_free(io_otype(io), io);                              \
 201 MACRO_END
 202
 203 /* Sanity check the ref count.  If it is 0, we may be doubly zfreeing.
 204  * If it is larger than max int, it has been corrupted, probably by being
 205  * modified into an address (this is architecture dependent, but it's
 206  * safe to assume there cannot really be max int references).
 207  *
 208  * NOTE: The 0 test alone will not catch double zfreeing of ipc_port
 209  * structs, because the io_references field is the first word of the struct,
 210  * and zfree modifies that to point to the next free zone element.
 211  */
 212 #define IO_MAX_REFERENCES                                               \
 213         (unsigned)(~0 ^ (1 << (sizeof(int)*BYTE_SIZE - 1)))
 214
 215 #define io_reference(io)                                                \
 216 MACRO_BEGIN                                                             \
 217         assert((io)->io_references < IO_MAX_REFERENCES);                \
 218         (io)->io_references++;                                          \
 219 MACRO_END
 220
 221 #define io_release(io)                                                  \
 222 MACRO_BEGIN                                                             \
 223         assert((io)->io_references > 0 &&                               \
 224                     (io)->io_references <= IO_MAX_REFERENCES);          \
 225         (io)->io_references--;                                          \
 226 MACRO_END
 227
 228 /*
 229  * Exported interfaces
 230  */
 231
 232 /* Take a reference to an object */
 233 extern void ipc_object_reference(
 234         ipc_object_t    object);
 235
 236 /* Release a reference to an object */
 237 extern void ipc_object_release(
 238         ipc_object_t    object);
 239
 240 /* Look up an object in a space */
 241 extern kern_return_t ipc_object_translate(
 242         ipc_space_t             space,
 243         mach_port_name_t        name,
 244         mach_port_right_t       right,
 245         ipc_object_t            *objectp);
 246
 247 /* Look up two objects in a space, locking them in the order described */
 248 extern kern_return_t ipc_object_translate_two(
 249         ipc_space_t             space,
 250         mach_port_name_t        name1,
 251         mach_port_right_t       right1,
 252         ipc_object_t            *objectp1,
 253         mach_port_name_t        name2,
 254         mach_port_right_t       right2,
 255         ipc_object_t            *objectp2);
 256
 257 /* Allocate a dead-name entry */
 258 extern kern_return_t
 259 ipc_object_alloc_dead(
 260         ipc_space_t             space,
 261         mach_port_name_t        *namep);
 262
 263 /*  Allocate a dead-name entry, with a specific name */
 264 extern kern_return_t ipc_object_alloc_dead_name(
 265         ipc_space_t             space,
 266         mach_port_name_t        name);
 267
 268 /* Allocate an object */
 269 extern kern_return_t ipc_object_alloc(
 270         ipc_space_t             space,
 271         ipc_object_type_t       otype,
 272         mach_port_type_t        type,
 273         mach_port_urefs_t       urefs,
 274         mach_port_name_t        *namep,
 275         ipc_object_t            *objectp);
 276
 277 /* Allocate an object, with a specific name */
 278 extern kern_return_t ipc_object_alloc_name(
 279         ipc_space_t             space,
 280         ipc_object_type_t       otype,
 281         mach_port_type_t        type,
 282         mach_port_urefs_t       urefs,
 283         mach_port_name_t        name,
 284         ipc_object_t            *objectp);
 285
 286 /* Convert a send type name to a received type name */
 287 extern mach_msg_type_name_t ipc_object_copyin_type(
 288         mach_msg_type_name_t    msgt_name);
 289
 290 /* Copyin a capability from a space */
 291 extern kern_return_t ipc_object_copyin(
 292         ipc_space_t             space,
 293         mach_port_name_t        name,
 294         mach_msg_type_name_t    msgt_name,
 295         ipc_object_t            *objectp);
 296
 297 /* Copyin a naked capability from the kernel */
 298 extern void ipc_object_copyin_from_kernel(
 299         ipc_object_t            object,
 300         mach_msg_type_name_t    msgt_name);
 301
 302 /* Destroy a naked capability */
 303 extern void ipc_object_destroy(
 304         ipc_object_t            object,
 305         mach_msg_type_name_t    msgt_name);
 306
 307 /* Copyout a capability, placing it into a space */
 308 extern kern_return_t ipc_object_copyout(
 309         ipc_space_t             space,
 310         ipc_object_t            object,
 311         mach_msg_type_name_t    msgt_name,
 312         boolean_t               overflow,
 313         mach_port_name_t        *namep);
 314
 315 /* Copyout a capability with a name, placing it into a space */
 316 extern kern_return_t ipc_object_copyout_name(
 317         ipc_space_t             space,
 318         ipc_object_t            object,
 319         mach_msg_type_name_t    msgt_name,
 320         boolean_t               overflow,
 321         mach_port_name_t        name);
 322
 323 /* Translate/consume the destination right of a message */
 324 extern void ipc_object_copyout_dest(
 325         ipc_space_t             space,
 326         ipc_object_t            object,
 327         mach_msg_type_name_t    msgt_name,
 328         mach_port_name_t        *namep);
 329
 330 /* Rename an entry in a space */
 331 extern kern_return_t ipc_object_rename(
 332         ipc_space_t             space,
 333         mach_port_name_t        oname,
 334         mach_port_name_t        nname);
 335
 336 #if     MACH_KDB
 337 /* Pretty-print an ipc object */
 338
 339 extern void ipc_object_print(
 340         ipc_object_t    object);
 341
 342 #endif  /* MACH_KDB */
 343
 344 #endif  /* _IPC_IPC_OBJECT_H_ */