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