iokit/IOKit/IOMemoryDescriptor.h

   1 /*
   2  * Copyright (c) 1998-2000 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.
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  21  */
  22 #ifndef _IOMEMORYDESCRIPTOR_H
  23 #define _IOMEMORYDESCRIPTOR_H
  24
  25 #include <IOKit/IOTypes.h>
  26 #include <libkern/c++/OSContainers.h>
  27
  28 struct IOPhysicalRange
  29 {
  30     IOPhysicalAddress   address;
  31     IOByteCount         length;
  32 };
  33
  34 class IOMemoryMap;
  35
  36 /*
  37  * Direction of transfer, with respect to the described memory.
  38  */
  39 enum IODirection
  40 {
  41     kIODirectionNone  = 0x0,    //                    same as VM_PROT_NONE
  42     kIODirectionIn    = 0x1,    // User land 'read',  same as VM_PROT_READ
  43     kIODirectionOut   = 0x2,    // User land 'write', same as VM_PROT_WRITE
  44     kIODirectionOutIn = kIODirectionIn | kIODirectionOut,
  45 };
  46
  47 /*! @class IOMemoryDescriptor : public OSObject
  48     @abstract An abstract base class defining common methods for describing physical or virtual memory.
  49     @discussion The IOMemoryDescriptor object represents a buffer or range of memory, specified as one or more physical or virtual address ranges. It contains methods to return the memory's physically contiguous segments (fragments), for use with the IOMemoryCursor, and methods to map the memory into any address space with caching and placed mapping options. */
  50
  51 class IOMemoryDescriptor : public OSObject
  52 {
  53     friend class _IOMemoryMap;
  54     friend class IOSubMemoryDescriptor;
  55
  56     OSDeclareDefaultStructors(IOMemoryDescriptor);
  57
  58 protected:
  59 /*! @struct ExpansionData
  60     @discussion This structure will be used to expand the capablilties of this class in the future.
  61     */
  62     struct ExpansionData {
  63         void *                          devicePager;
  64         unsigned int                    pagerContig:1;
  65         unsigned int                    unused:31;
  66         IOMemoryDescriptor *            memory;
  67     };
  68
  69 /*! @var reserved
  70     Reserved for future use.  (Internal use only)  */
  71     ExpansionData * reserved;
  72
  73 protected:
  74     OSSet *             _mappings;
  75     IOOptionBits        _flags;
  76     void *              _memEntry;
  77
  78     IODirection         _direction;        /* direction of transfer */
  79     IOByteCount         _length;           /* length of all ranges */
  80     IOOptionBits        _tag;
  81
  82 public:
  83
  84     virtual IOPhysicalAddress getSourceSegment( IOByteCount offset,
  85                                                 IOByteCount * length );
  86
  87 private:
  88     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 0);
  89     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 1);
  90     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 2);
  91     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 3);
  92     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 4);
  93     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 5);
  94     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 6);
  95     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 7);
  96     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 8);
  97     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 9);
  98     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 10);
  99     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 11);
 100     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 12);
 101     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 13);
 102     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 14);
 103     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 15);
 104
 105 protected:
 106     virtual void free();
 107 public:
 108     static void initialize( void );
 109
 110 public:
 111 /*! @function withAddress
 112     @abstract Create an IOMemoryDescriptor to describe one virtual range of the kernel task.
 113     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the kernel map.
 114     @param address The virtual address of the first byte in the memory.
 115     @param withLength The length of memory.
 116     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 117     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 118
 119     static IOMemoryDescriptor * withAddress(void *       address,
 120                                             IOByteCount  withLength,
 121                                             IODirection  withDirection);
 122
 123 /*! @function withAddress
 124     @abstract Create an IOMemoryDescriptor to describe one virtual range of the specified map.
 125     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the specified map.
 126     @param address The virtual address of the first byte in the memory.
 127     @param withLength The length of memory.
 128     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 129     @param withTask The task the virtual ranges are mapped into.
 130     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 131
 132     static IOMemoryDescriptor * withAddress(vm_address_t address,
 133                                             IOByteCount  withLength,
 134                                             IODirection  withDirection,
 135                                             task_t       withTask);
 136
 137 /*! @function withPhysicalAddress
 138     @abstract Create an IOMemoryDescriptor to describe one physical range.
 139     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single physical memory range.
 140     @param address The physical address of the first byte in the memory.
 141     @param withLength The length of memory.
 142     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 143     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 144
 145     static IOMemoryDescriptor * withPhysicalAddress(
 146                                 IOPhysicalAddress       address,
 147                                 IOByteCount             withLength,
 148                                 IODirection             withDirection );
 149
 150 /*! @function withRanges
 151     @abstract Create an IOMemoryDescriptor to describe one or more virtual ranges.
 152     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of an array of virtual memory ranges each mapped into a specified source task.
 153     @param ranges An array of IOVirtualRange structures which specify the virtual ranges in the specified map which make up the memory to be described.
 154     @param withCount The member count of the ranges array.
 155     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 156     @param withTask The task each of the virtual ranges are mapped into.
 157     @param asReference If false, the IOMemoryDescriptor object will make a copy of the ranges array, otherwise, the array will be used in situ, avoiding an extra allocation.
 158     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 159
 160      static IOMemoryDescriptor * withRanges(IOVirtualRange *    ranges,
 161                                             UInt32              withCount,
 162                                             IODirection         withDirection,
 163                                             task_t            withTask,
 164                                             bool                asReference = false);
 165
 166 /*! @function withPhysicalRanges
 167     @abstract Create an IOMemoryDescriptor to describe one or more physical ranges.
 168     @discussion  This method creates and initializes an IOMemoryDescriptor for memory consisting of an array of physical memory ranges.
 169     @param ranges An array of IOPhysicalRange structures which specify the physical ranges which make up the memory to be described.
 170     @param withCount The member count of the ranges array.
 171     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 172     @param asReference If false, the IOMemoryDescriptor object will make a copy of the ranges array, otherwise, the array will be used in situ, avoiding an extra allocation.
 173     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 174
 175     static IOMemoryDescriptor * withPhysicalRanges(
 176                                             IOPhysicalRange *   ranges,
 177                                             UInt32              withCount,
 178                                             IODirection         withDirection,
 179                                             bool                asReference = false);
 180
 181 /*! @function withSubRange
 182     @abstract Create an IOMemoryDescriptor to describe a subrange of an existing descriptor.
 183     @discussion  This method creates and initializes an IOMemoryDescriptor for memory consisting of a subrange of the specified memory descriptor. The parent memory descriptor is retained by the new descriptor.
 184     @param of The parent IOMemoryDescriptor of which a subrange is to be used for the new descriptor, which will be retained by the subrange IOMemoryDescriptor.
 185     @param offset A byte offset into the parent memory descriptor's memory.
 186     @param length The length of the subrange.
 187     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures. This is used over the direction of the parent descriptor.
 188     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 189
 190     static IOMemoryDescriptor * withSubRange(IOMemoryDescriptor *       of,
 191                                              IOByteCount                offset,
 192                                              IOByteCount                length,
 193                                              IODirection                withDirection);
 194
 195 /*! @function initWithAddress
 196     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one virtual range of the kernel task.
 197     @discussion This method initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the kernel map. An IOMemoryDescriptor can be re-used by calling initWithAddress or initWithRanges again on an existing instance -- note this behavior is not commonly supported in other IOKit classes, although it is supported here.
 198     @param address The virtual address of the first byte in the memory.
 199     @param withLength The length of memory.
 200     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 201     @result true on success, false on failure. */
 202
 203     virtual bool initWithAddress(void *       address,
 204                                  IOByteCount  withLength,
 205                                  IODirection  withDirection) = 0;
 206
 207 /*! @function initWithAddress
 208     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one virtual range of the specified map.
 209     @discussion This method initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the specified map. An IOMemoryDescriptor can be re-used by calling initWithAddress or initWithRanges again on an existing instance -- note this behavior is not commonly supported in other IOKit classes, although it is supported here.
 210     @param address The virtual address of the first byte in the memory.
 211     @param withLength The length of memory.
 212     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 213     @param withTask The task the virtual ranges are mapped into.
 214     @result true on success, false on failure. */
 215
 216     virtual bool initWithAddress(vm_address_t address,
 217                                  IOByteCount  withLength,
 218                                  IODirection  withDirection,
 219                                  task_t       withTask) = 0;
 220
 221 /*! @function initWithPhysicalAddress
 222     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one physical range.
 223     @discussion This method initializes an IOMemoryDescriptor for memory consisting of a single physical memory range. An IOMemoryDescriptor can be re-used by calling initWithAddress or initWithRanges again on an existing instance -- note this behavior is not commonly supported in other IOKit classes, although it is supported here.
 224     @param address The physical address of the first byte in the memory.
 225     @param withLength The length of memory.
 226     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 227     @result true on success, false on failure. */
 228
 229     virtual bool initWithPhysicalAddress(
 230                                  IOPhysicalAddress      address,
 231                                  IOByteCount            withLength,
 232                                  IODirection            withDirection ) = 0;
 233
 234 /*! @function initWithRanges
 235     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one or more virtual ranges.
 236     @discussion This method initializes an IOMemoryDescriptor for memory consisting of an array of virtual memory ranges each mapped into a specified source task. An IOMemoryDescriptor can be re-used by calling initWithAddress or initWithRanges again on an existing instance -- note this behavior is not commonly supported in other IOKit classes, although it is supported here.
 237     @param ranges An array of IOVirtualRange structures which specify the virtual ranges in the specified map which make up the memory to be described.
 238     @param withCount The member count of the ranges array.
 239     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 240     @param withTask The task each of the virtual ranges are mapped into.
 241     @param asReference If false, the IOMemoryDescriptor object will make a copy of the ranges array, otherwise, the array will be used in situ, avoiding an extra allocation.
 242     @result true on success, false on failure. */
 243
 244     virtual bool initWithRanges(        IOVirtualRange * ranges,
 245                                         UInt32           withCount,
 246                                         IODirection      withDirection,
 247                                         task_t           withTask,
 248                                         bool             asReference = false) = 0;
 249
 250 /*! @function initWithPhysicalRanges
 251     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one or more physical ranges.
 252     @discussion  This method initializes an IOMemoryDescriptor for memory consisting of an array of physical memory ranges. An IOMemoryDescriptor can be re-used by calling initWithAddress or initWithRanges again on an existing instance -- note this behavior is not commonly supported in other IOKit classes, although it is supported here.
 253     @param ranges An array of IOPhysicalRange structures which specify the physical ranges which make up the memory to be described.
 254     @param withCount The member count of the ranges array.
 255     @param withDirection An I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 256     @param asReference If false, the IOMemoryDescriptor object will make a copy of the ranges array, otherwise, the array will be used in situ, avoiding an extra allocation.
 257     @result true on success, false on failure. */
 258
 259     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 260                                         UInt32           withCount,
 261                                         IODirection      withDirection,
 262                                         bool             asReference = false) = 0;
 263
 264 /*! @function getDirection
 265     @abstract Accessor to get the direction the memory descriptor was created with.
 266     @discussion This method returns the direction the memory descriptor was created with.
 267     @result The direction. */
 268
 269     virtual IODirection getDirection() const;
 270
 271 /*! @function getLength
 272     @abstract Accessor to get the length of the memory descriptor (over all its ranges).
 273     @discussion This method returns the total length of the memory described by the descriptor, ie. the sum of its ranges' lengths.
 274     @result The byte count. */
 275
 276     virtual IOByteCount getLength() const;
 277
 278 /*! @function setTag
 279     @abstract Set the tag for the memory descriptor.
 280     @discussion This method sets the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
 281     @param tag The tag. */
 282
 283     virtual void setTag( IOOptionBits tag );
 284
 285 /*! @function getTag
 286     @abstract Accessor to the retrieve the tag for the memory descriptor.
 287     @discussion This method returns the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
 288     @result The tag. */
 289
 290     virtual IOOptionBits getTag( void );
 291
 292 /*! @function readBytes
 293     @abstract Copy data from the memory descriptor's buffer to the specified buffer.
 294     @discussion This method copies data from the memory descriptor's memory at the given offset, to the caller's buffer.
 295     @param offset A byte offset into the memory descriptor's memory.
 296     @param bytes The caller supplied buffer to copy the data to.
 297     @param withLength The length of the data to copy.
 298     @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. */
 299
 300     virtual IOByteCount readBytes(IOByteCount offset,
 301                                 void * bytes, IOByteCount withLength);
 302
 303 /*! @function writeBytes
 304     @abstract Copy data to the memory descriptor's buffer from the specified buffer.
 305     @discussion This method copies data to the memory descriptor's memory at the given offset, from the caller's buffer.
 306     @param offset A byte offset into the memory descriptor's memory.
 307     @param bytes The caller supplied buffer to copy the data from.
 308     @param withLength The length of the data to copy.
 309     @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. */
 310
 311     virtual IOByteCount writeBytes(IOByteCount offset,
 312                                 const void * bytes, IOByteCount withLength);
 313
 314 /*! @function getPhysicalSegment
 315     @abstract Break a memory descriptor into its physically contiguous segments.
 316     @discussion This method returns the physical address of the byte at the given offset into the memory, and optionally the length of the physically contiguous segment from that offset.
 317     @param offset A byte offset into the memory whose physical address to return.
 318     @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
 319     @result A physical address, or zero if the offset is beyond the length of the memory. */
 320
 321     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 322                                                  IOByteCount * length) = 0;
 323
 324 /*! @function getPhysicalAddress
 325     @abstract Return the physical address of the first byte in the memory.
 326     @discussion This method returns the physical address of the  first byte in the memory. It is most useful on memory known to be physically contiguous.
 327     @result A physical address. */
 328
 329     /* inline */ IOPhysicalAddress getPhysicalAddress();
 330         /* { return( getPhysicalSegment( 0, 0 )); } */
 331
 332     /* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
 333     /* DEPRECATED */ virtual void * getVirtualSegment(IOByteCount offset,
 334     /* DEPRECATED */                                    IOByteCount * length) = 0;
 335     /* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
 336
 337 /*! @function prepare
 338     @abstract Prepare the memory for an I/O transfer.
 339     @discussion This involves paging in the memory, if necessary, and wiring it down for the duration of the transfer.  The complete() method completes the processing of the memory after the I/O transfer finishes.  This method needn't called for non-pageable memory.
 340     @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
 341     @result An IOReturn code. */
 342
 343     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) = 0;
 344
 345 /*! @function complete
 346     @abstract Complete processing of the memory after an I/O transfer finishes.
 347     @discussion This method should not be called unless a prepare was previously issued; the prepare() and complete() must occur in pairs, before and after an I/O transfer involving pageable memory.
 348     @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
 349     @result An IOReturn code. */
 350
 351     virtual IOReturn complete(IODirection forDirection = kIODirectionNone) = 0;
 352
 353     /*
 354      * Mapping functions.
 355      */
 356
 357 /*! @function map
 358     @abstract Maps a IOMemoryDescriptor into a task.
 359     @discussion This is the general purpose method to map all or part of the memory described by a memory descriptor into a task at any available address, or at a fixed address if possible. Caching & read-only options may be set for the mapping. The mapping is represented as a returned reference to a IOMemoryMap object, which may be shared if the mapping is compatible with an existing mapping of the IOMemoryDescriptor. The IOMemoryMap object returned should be released only when the caller has finished accessing the mapping, as freeing the object destroys the mapping.
 360     @param intoTask Sets the target task for the mapping. Pass kernel_task for the kernel address space.
 361     @param atAddress If a placed mapping is requested, atAddress specifies its address, and the kIOMapAnywhere should not be set. Otherwise, atAddress is ignored.
 362     @param options Mapping options are defined in IOTypes.h,<br>
 363         kIOMapAnywhere should be passed if the mapping can be created anywhere. If not set, the atAddress parameter sets the location of the mapping, if it is available in the target map.<br>
 364         kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
 365         kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
 366         kIOMapReadOnly to allow only read only accesses to the memory - writes will cause and access fault.<br>
 367         kIOMapReference will only succeed if the mapping already exists, and the IOMemoryMap object is just an extra reference, ie. no new mapping will be created.<br>
 368     @param offset Is a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default to map all the memory.
 369     @param length Is the length of the mapping requested for a subset of the IOMemoryDescriptor. Zero is the default to map all the memory.
 370     @result A reference to an IOMemoryMap object representing the mapping, which can supply the virtual address of the mapping and other information. The mapping may be shared with multiple callers - multiple maps are avoided if a compatible one exists. The IOMemoryMap object returned should be released only when the caller has finished accessing the mapping, as freeing the object destroys the mapping. The IOMemoryMap instance also retains the IOMemoryDescriptor it maps while it exists. */
 371
 372     virtual IOMemoryMap *       map(
 373         task_t          intoTask,
 374         IOVirtualAddress        atAddress,
 375         IOOptionBits            options,
 376         IOByteCount             offset = 0,
 377         IOByteCount             length = 0 );
 378
 379 /*! @function map
 380     @abstract Maps a IOMemoryDescriptor into the kernel map.
 381     @discussion This is a shortcut method to map all the memory described by a memory descriptor into the kernel map at any available address. See the full version of the map method for further details.
 382     @param options Mapping options as in the full version of the map method, with kIOMapAnywhere assumed.
 383     @result See the full version of the map method. */
 384
 385     virtual IOMemoryMap *       map(
 386         IOOptionBits            options = 0 );
 387
 388 /*! @function setMapping
 389     @abstract Establishes an already existing mapping.
 390     @discussion This method tells the IOMemoryDescriptor about a mapping that exists, but was created elsewhere. It allows later callers of the map method to share this externally created mapping. The IOMemoryMap object returned is created to represent it. This method is not commonly needed.
 391     @param task Address space in which the mapping exists.
 392     @param mapAddress Virtual address of the mapping.
 393     @param options Caching and read-only attributes of the mapping.
 394     @result A IOMemoryMap object created to represent the mapping. */
 395
 396     virtual IOMemoryMap *       setMapping(
 397         task_t          task,
 398         IOVirtualAddress        mapAddress,
 399         IOOptionBits            options = 0 );
 400
 401     // Following methods are private implementation
 402
 403     // make virtual
 404     IOReturn redirect( task_t safeTask, bool redirect );
 405
 406     IOReturn handleFault(
 407         void *                  pager,
 408         vm_map_t                addressMap,
 409         IOVirtualAddress        address,
 410         IOByteCount             sourceOffset,
 411         IOByteCount             length,
 412         IOOptionBits            options );
 413
 414 protected:
 415     virtual IOMemoryMap *       makeMapping(
 416         IOMemoryDescriptor *    owner,
 417         task_t          intoTask,
 418         IOVirtualAddress        atAddress,
 419         IOOptionBits            options,
 420         IOByteCount             offset,
 421         IOByteCount             length );
 422
 423     virtual void                addMapping(
 424         IOMemoryMap *           mapping );
 425
 426     virtual void                removeMapping(
 427         IOMemoryMap *           mapping );
 428
 429     virtual IOReturn doMap(
 430         vm_map_t                addressMap,
 431         IOVirtualAddress *      atAddress,
 432         IOOptionBits            options,
 433         IOByteCount             sourceOffset = 0,
 434         IOByteCount             length = 0 );
 435
 436     virtual IOReturn doUnmap(
 437         vm_map_t                addressMap,
 438         IOVirtualAddress        logical,
 439         IOByteCount             length );
 440 };
 441
 442 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 443
 444 /*! @class IOMemoryMap : public OSObject
 445     @abstract An abstract base class defining common methods for describing a memory mapping.
 446     @discussion The IOMemoryMap object represents a mapped range of memory, described by a IOMemoryDescriptor. The mapping may be in the kernel or a non-kernel task and has processor cache mode attributes. IOMemoryMap instances are created by IOMemoryDescriptor when it creates mappings in its map method, and returned to the caller. */
 447
 448 class IOMemoryMap : public OSObject
 449 {
 450     OSDeclareAbstractStructors(IOMemoryMap)
 451
 452 public:
 453 /*! @function getVirtualAddress
 454     @abstract Accessor to the virtual address of the first byte in the mapping.
 455     @discussion This method returns the virtual address of the first byte in the mapping.
 456     @result A virtual address. */
 457
 458     virtual IOVirtualAddress    getVirtualAddress() = 0;
 459
 460 /*! @function getPhysicalSegment
 461     @abstract Break a mapping into its physically contiguous segments.
 462     @discussion This method returns the physical address of the byte at the given offset into the mapping, and optionally the length of the physically contiguous segment from that offset. It functions similarly to IOMemoryDescriptor::getPhysicalSegment.
 463     @param offset A byte offset into the mapping whose physical address to return.
 464     @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
 465     @result A physical address, or zero if the offset is beyond the length of the mapping. */
 466
 467     virtual IOPhysicalAddress   getPhysicalSegment(IOByteCount offset,
 468                                                    IOByteCount * length) = 0;
 469
 470 /*! @function getPhysicalAddress
 471     @abstract Return the physical address of the first byte in the mapping.
 472     @discussion This method returns the physical address of the  first byte in the mapping. It is most useful on mappings known to be physically contiguous.
 473     @result A physical address. */
 474
 475     /* inline */ IOPhysicalAddress getPhysicalAddress();
 476         /* { return( getPhysicalSegment( 0, 0 )); } */
 477
 478 /*! @function getLength
 479     @abstract Accessor to the length of the mapping.
 480     @discussion This method returns the length of the mapping.
 481     @result A byte count. */
 482
 483     virtual IOByteCount         getLength() = 0;
 484
 485 /*! @function getAddressTask
 486     @abstract Accessor to the task of the mapping.
 487     @discussion This method returns the mach task the mapping exists in.
 488     @result A mach task_t. */
 489
 490     virtual task_t              getAddressTask() = 0;
 491
 492 /*! @function getMemoryDescriptor
 493     @abstract Accessor to the IOMemoryDescriptor the mapping was created from.
 494     @discussion This method returns the IOMemoryDescriptor the mapping was created from.
 495     @result An IOMemoryDescriptor reference, which is valid while the IOMemoryMap object is retained. It should not be released by the caller. */
 496
 497     virtual IOMemoryDescriptor * getMemoryDescriptor() = 0;
 498
 499 /*! @function getMapOptions
 500     @abstract Accessor to the options the mapping was created with.
 501     @discussion This method returns the options to IOMemoryDescriptor::map the mapping was created with.
 502     @result Options for the mapping, including cache settings. */
 503
 504     virtual IOOptionBits        getMapOptions() = 0;
 505
 506 /*! @function unmap
 507     @abstract Force the IOMemoryMap to unmap, without destroying the object.
 508     @discussion IOMemoryMap instances will unmap themselves upon free, ie. when the last client with a reference calls release. This method forces the IOMemoryMap to destroy the mapping it represents, regardless of the number of clients. It is not generally used.
 509     @result An IOReturn code. */
 510
 511     virtual IOReturn            unmap() = 0;
 512
 513     virtual void                        taskDied() = 0;
 514 };
 515
 516 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 517
 518 // The following classes are private implementation of IOMemoryDescriptor - they
 519 // should not be referenced directly, just through the public API's in the
 520 // IOMemoryDescriptor class. For example, an IOGeneralMemoryDescriptor instance
 521 // might be created by IOMemoryDescriptor::withAddress(), but there should be
 522 // no need to reference as anything but a generic IOMemoryDescriptor *.
 523
 524 enum {
 525     kIOMemoryRequiresWire       = 0x00000001
 526 };
 527
 528 class IOGeneralMemoryDescriptor : public IOMemoryDescriptor
 529 {
 530     OSDeclareDefaultStructors(IOGeneralMemoryDescriptor);
 531
 532 protected:
 533     union {
 534     IOVirtualRange *    v;
 535     IOPhysicalRange *   p;
 536     }                   _ranges;            /* list of address ranges */
 537     unsigned            _rangesCount;       /* number of address ranges in list */
 538     bool                _rangesIsAllocated; /* is list allocated by us? */
 539
 540     task_t              _task;               /* task where all ranges are mapped to */
 541
 542     union {
 543     IOVirtualRange      v;
 544     IOPhysicalRange     p;
 545     }                   _singleRange;      /* storage space for a single range */
 546
 547     unsigned            _wireCount;        /* number of outstanding wires */
 548
 549     vm_address_t        _cachedVirtualAddress;  /* a cached virtual-to-physical */
 550     IOPhysicalAddress   _cachedPhysicalAddress; /*    mapping, for optimization */
 551
 552     bool                _initialized;      /* has superclass been initialized? */
 553
 554     virtual void free();
 555
 556 protected:
 557     /* DEPRECATED */ IOByteCount _position; /* absolute position over all ranges */
 558     /* DEPRECATED */ virtual void setPosition(IOByteCount position);
 559
 560 private:
 561     /* DEPRECATED */ unsigned    _positionAtIndex;  /* range #n in which position is now */
 562     /* DEPRECATED */ IOByteCount _positionAtOffset; /* relative position within range #n */
 563     OSData *_memoryEntries;
 564
 565     /* DEPRECATED */ vm_offset_t _kernPtrAligned;
 566     /* DEPRECATED */ unsigned    _kernPtrAtIndex;
 567     /* DEPRECATED */ IOByteCount  _kernSize;
 568     /* DEPRECATED */ virtual void mapIntoKernel(unsigned rangeIndex);
 569     /* DEPRECATED */ virtual void unmapFromKernel();
 570     inline vm_map_t getMapForTask( task_t task, vm_address_t address );
 571
 572 public:
 573     /*
 574      * IOMemoryDescriptor required methods
 575      */
 576
 577     virtual bool initWithAddress(void *       address,
 578                                  IOByteCount    withLength,
 579                                  IODirection  withDirection);
 580
 581     virtual bool initWithAddress(vm_address_t address,
 582                                  IOByteCount    withLength,
 583                                  IODirection  withDirection,
 584                                  task_t       withTask);
 585
 586     virtual bool initWithPhysicalAddress(
 587                                  IOPhysicalAddress      address,
 588                                  IOByteCount            withLength,
 589                                  IODirection            withDirection );
 590
 591     virtual bool initWithRanges(        IOVirtualRange * ranges,
 592                                         UInt32           withCount,
 593                                         IODirection      withDirection,
 594                                         task_t           withTask,
 595                                         bool             asReference = false);
 596
 597     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 598                                         UInt32           withCount,
 599                                         IODirection      withDirection,
 600                                         bool             asReference = false);
 601
 602     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 603                                                  IOByteCount * length);
 604
 605     virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
 606                                                IOByteCount * length);
 607
 608     /* DEPRECATED */ virtual void * getVirtualSegment(IOByteCount offset,
 609     /* DEPRECATED */                                    IOByteCount * length);
 610
 611     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);
 612
 613     virtual IOReturn complete(IODirection forDirection = kIODirectionNone);
 614
 615     virtual IOReturn doMap(
 616         vm_map_t                addressMap,
 617         IOVirtualAddress *      atAddress,
 618         IOOptionBits            options,
 619         IOByteCount             sourceOffset = 0,
 620         IOByteCount             length = 0 );
 621
 622     virtual IOReturn doUnmap(
 623         vm_map_t                addressMap,
 624         IOVirtualAddress        logical,
 625         IOByteCount             length );
 626     virtual bool serialize(OSSerialize *s) const;
 627 };
 628
 629 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 630
 631 class IOSubMemoryDescriptor : public IOMemoryDescriptor
 632 {
 633     friend class IOMemoryDescriptor;
 634
 635     OSDeclareDefaultStructors(IOSubMemoryDescriptor);
 636
 637 protected:
 638     IOMemoryDescriptor * _parent;
 639     IOByteCount          _start;
 640
 641     virtual void free();
 642
 643     virtual bool initSubRange( IOMemoryDescriptor * parent,
 644                                 IOByteCount offset, IOByteCount length,
 645                                 IODirection withDirection );
 646
 647     virtual bool initWithAddress(void *       address,
 648                                  IOByteCount    withLength,
 649                                  IODirection  withDirection);
 650
 651     virtual bool initWithAddress(vm_address_t address,
 652                                  IOByteCount    withLength,
 653                                  IODirection  withDirection,
 654                                  task_t       withTask);
 655
 656     virtual bool initWithPhysicalAddress(
 657                                  IOPhysicalAddress      address,
 658                                  IOByteCount            withLength,
 659                                  IODirection            withDirection );
 660
 661     virtual bool initWithRanges(        IOVirtualRange * ranges,
 662                                         UInt32           withCount,
 663                                         IODirection      withDirection,
 664                                         task_t           withTask,
 665                                         bool             asReference = false);
 666
 667     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 668                                         UInt32           withCount,
 669                                         IODirection      withDirection,
 670                                         bool             asReference = false);
 671
 672     IOMemoryDescriptor::withAddress;
 673     IOMemoryDescriptor::withPhysicalAddress;
 674     IOMemoryDescriptor::withPhysicalRanges;
 675     IOMemoryDescriptor::withRanges;
 676     IOMemoryDescriptor::withSubRange;
 677
 678 public:
 679     /*
 680      * IOMemoryDescriptor required methods
 681      */
 682
 683     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 684                                                  IOByteCount * length);
 685
 686     virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
 687                                                IOByteCount * length);
 688
 689     virtual IOByteCount readBytes(IOByteCount offset,
 690                                 void * bytes, IOByteCount withLength);
 691
 692     virtual IOByteCount writeBytes(IOByteCount offset,
 693                                 const void * bytes, IOByteCount withLength);
 694
 695     virtual void * getVirtualSegment(IOByteCount offset,
 696                                         IOByteCount * length);
 697
 698     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);
 699
 700     virtual IOReturn complete(IODirection forDirection = kIODirectionNone);
 701
 702     // make virtual
 703     IOReturn redirect( task_t safeTask, bool redirect );
 704
 705     virtual bool serialize(OSSerialize *s) const;
 706
 707 protected:
 708     virtual IOMemoryMap *       makeMapping(
 709         IOMemoryDescriptor *    owner,
 710         task_t          intoTask,
 711         IOVirtualAddress        atAddress,
 712         IOOptionBits            options,
 713         IOByteCount             offset,
 714         IOByteCount             length );
 715 };
 716
 717 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 718
 719 #endif /* !_IOMEMORYDESCRIPTOR_H */