iokit/IOKit/IOMemoryDescriptor.h

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  28 #ifndef _IOMEMORYDESCRIPTOR_H
  29 #define _IOMEMORYDESCRIPTOR_H
  30
  31 #include <sys/cdefs.h>
  32
  33 #include <IOKit/IOTypes.h>
  34 #include <IOKit/IOLocks.h>
  35 #include <libkern/c++/OSContainers.h>
  36
  37 __BEGIN_DECLS
  38 #include <mach/memory_object_types.h>
  39 __END_DECLS
  40
  41 struct IOPhysicalRange
  42 {
  43     IOPhysicalAddress   address;
  44     IOByteCount         length;
  45 };
  46
  47 class IOMemoryMap;
  48 class IOMapper;
  49
  50 /*
  51  * Direction of transfer, with respect to the described memory.
  52  */
  53 enum IODirection
  54 {
  55     kIODirectionNone  = 0x0,    //                    same as VM_PROT_NONE
  56     kIODirectionIn    = 0x1,    // User land 'read',  same as VM_PROT_READ
  57     kIODirectionOut   = 0x2,    // User land 'write', same as VM_PROT_WRITE
  58     kIODirectionOutIn = kIODirectionOut | kIODirectionIn,
  59     kIODirectionInOut = kIODirectionIn  | kIODirectionOut
  60 };
  61
  62 /*
  63  * IOOptionBits used in the withOptions variant
  64  */
  65 enum {
  66     kIOMemoryDirectionMask      = 0x00000007,
  67     kIOMemoryAutoPrepare        = 0x00000008,   // Shared with Buffer MD
  68
  69     kIOMemoryTypeVirtual        = 0x00000010,
  70     kIOMemoryTypePhysical       = 0x00000020,
  71     kIOMemoryTypeUPL            = 0x00000030,
  72     kIOMemoryTypePersistentMD   = 0x00000040,   // Persistent Memory Descriptor
  73     kIOMemoryTypeUIO            = 0x00000050,
  74     kIOMemoryTypeVirtual64      = 0x00000060,
  75     kIOMemoryTypePhysical64     = 0x00000070,
  76     kIOMemoryTypeMask           = 0x000000f0,
  77
  78     kIOMemoryAsReference        = 0x00000100,
  79     kIOMemoryBufferPageable     = 0x00000400,
  80     kIOMemoryDontMap            = 0x00000800,
  81 #ifdef XNU_KERNEL_PRIVATE
  82     kIOMemoryRedirected         = 0x00004000,
  83     kIOMemoryPreparedReadOnly   = 0x00008000,
  84 #endif
  85     kIOMemoryPersistent         = 0x00010000,
  86 #ifdef XNU_KERNEL_PRIVATE
  87     kIOMemoryReserved6156215    = 0x00020000,
  88 #endif
  89     kIOMemoryThreadSafe         = 0x00100000,   // Shared with Buffer MD
  90 };
  91
  92 #define kIOMapperNone   ((IOMapper *) -1)
  93 #define kIOMapperSystem ((IOMapper *) 0)
  94
  95 enum
  96 {
  97     kIOMemoryPurgeableKeepCurrent = 1,
  98     kIOMemoryPurgeableNonVolatile = 2,
  99     kIOMemoryPurgeableVolatile    = 3,
 100     kIOMemoryPurgeableEmpty       = 4
 101 };
 102 enum
 103 {
 104     kIOMemoryIncoherentIOFlush   = 1,
 105     kIOMemoryIncoherentIOStore   = 2,
 106 };
 107
 108 #define IOMEMORYDESCRIPTOR_SUPPORTS_DMACOMMAND  1
 109
 110
 111 /*! @class IOMemoryDescriptor : public OSObject
 112     @abstract An abstract base class defining common methods for describing physical or virtual memory.
 113     @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. */
 114
 115 class IOMemoryDescriptor : public OSObject
 116 {
 117     friend class _IOMemoryMap;
 118     friend class IOSubMemoryDescriptor;
 119
 120     OSDeclareDefaultStructors(IOMemoryDescriptor);
 121
 122 protected:
 123 /*! @struct ExpansionData
 124     @discussion This structure will be used to expand the capablilties of this class in the future.
 125     */
 126     struct ExpansionData {
 127         void *                          devicePager;
 128         unsigned int                    pagerContig:1;
 129         unsigned int                    unused:31;
 130         IOMemoryDescriptor *            memory;
 131     };
 132
 133 /*! @var reserved
 134     Reserved for future use.  (Internal use only)  */
 135     ExpansionData * reserved;
 136
 137 protected:
 138     OSSet *             _mappings;
 139     IOOptionBits        _flags;
 140     void *              _memEntry;
 141
 142     IODirection         _direction;        /* DEPRECATED: use _flags instead. direction of transfer */
 143     IOByteCount         _length;           /* length of all ranges */
 144     IOOptionBits        _tag;
 145
 146 public:
 147 typedef IOOptionBits DMACommandOps;
 148     virtual IOPhysicalAddress getSourceSegment( IOByteCount offset,
 149                                                 IOByteCount * length );
 150     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 0);
 151
 152 /*! @function initWithOptions
 153     @abstract Master initialiser for all variants of memory descriptors.  For a more complete description see IOMemoryDescriptor::withOptions.
 154     @discussion Note this function can be used to re-init a previously created memory descriptor.
 155     @result true on success, false on failure. */
 156     virtual bool initWithOptions(void *         buffers,
 157                                  UInt32         count,
 158                                  UInt32         offset,
 159                                  task_t         task,
 160                                  IOOptionBits   options,
 161                                  IOMapper *     mapper = kIOMapperSystem);
 162     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 1);
 163
 164     virtual addr64_t getPhysicalSegment64( IOByteCount offset,
 165                                             IOByteCount * length );
 166     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 2);
 167
 168
 169 /*! @function setPurgeable
 170     @abstract Control the purgeable status of a memory descriptors memory.
 171     @discussion Buffers may be allocated with the ability to have their purgeable status changed - IOBufferMemoryDescriptor with the kIOMemoryPurgeable option, VM_FLAGS_PURGEABLE may be passed to vm_allocate() in user space to allocate such buffers. The purgeable status of such a buffer may be controlled with setPurgeable(). The process of making a purgeable memory descriptor non-volatile and determining its previous state is atomic - if a purgeable memory descriptor is made nonvolatile and the old state is returned as kIOMemoryPurgeableVolatile, then the memory's previous contents are completely intact and will remain so until the memory is made volatile again.  If the old state is returned as kIOMemoryPurgeableEmpty then the memory was reclaimed while it was in a volatile state and its previous contents have been lost.
 172     @param newState - the desired new purgeable state of the memory:<br>
 173     kIOMemoryPurgeableKeepCurrent - make no changes to the memory's purgeable state.<br>
 174     kIOMemoryPurgeableVolatile    - make the memory volatile - the memory may be reclaimed by the VM system without saving its contents to backing store.<br>
 175     kIOMemoryPurgeableNonVolatile - make the memory nonvolatile - the memory is treated as with usual allocations and must be saved to backing store if paged.<br>
 176     kIOMemoryPurgeableEmpty       - make the memory volatile, and discard any pages allocated to it.
 177     @param oldState - if non-NULL, the previous purgeable state of the memory is returned here:<br>
 178     kIOMemoryPurgeableNonVolatile - the memory was nonvolatile.<br>
 179     kIOMemoryPurgeableVolatile    - the memory was volatile but its content has not been discarded by the VM system.<br>
 180     kIOMemoryPurgeableEmpty       - the memory was volatile and has been discarded by the VM system.<br>
 181     @result An IOReturn code. */
 182
 183     virtual IOReturn setPurgeable( IOOptionBits newState,
 184                                     IOOptionBits * oldState );
 185     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 3);
 186
 187 /*! @function performOperation
 188     @abstract Perform an operation on the memory descriptor's memory.
 189     @discussion This method performs some operation on a range of the memory descriptor's memory. When a memory descriptor's memory is not mapped, it should be more efficient to use this method than mapping the memory to perform the operation virtually.
 190     @param options The operation to perform on the memory:<br>
 191     kIOMemoryIncoherentIOFlush - pass this option to store to memory and flush any data in the processor cache for the memory range, with synchronization to ensure the data has passed through all levels of processor cache. It may not be supported on all architectures. This type of flush may be used for non-coherent I/O such as AGP - it is NOT required for PCI coherent operations. The memory descriptor must have been previously prepared.<br>
 192     kIOMemoryIncoherentIOStore - pass this option to store to memory any data in the processor cache for the memory range, with synchronization to ensure the data has passed through all levels of processor cache. It may not be supported on all architectures. This type of flush may be used for non-coherent I/O such as AGP - it is NOT required for PCI coherent operations. The memory descriptor must have been previously prepared.
 193     @param offset A byte offset into the memory descriptor's memory.
 194     @param length The length of the data range.
 195     @result An IOReturn code. */
 196
 197     virtual IOReturn performOperation( IOOptionBits options,
 198                                         IOByteCount offset, IOByteCount length );
 199     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 4);
 200
 201     // Used for dedicated communications for IODMACommand
 202     virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
 203     OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 5);
 204
 205 private:
 206     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 6);
 207     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 7);
 208     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 8);
 209     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 9);
 210     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 10);
 211     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 11);
 212     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 12);
 213     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 13);
 214     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 14);
 215     OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 15);
 216
 217 protected:
 218     virtual void free();
 219 public:
 220     static void initialize( void );
 221
 222 public:
 223 /*! @function withAddress
 224     @abstract Create an IOMemoryDescriptor to describe one virtual range of the kernel task.
 225     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the kernel map.
 226     @param address The virtual address of the first byte in the memory.
 227     @param withLength The length of memory.
 228     @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.
 229     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 230
 231     static IOMemoryDescriptor * withAddress(void *       address,
 232                                             IOByteCount  withLength,
 233                                             IODirection  withDirection);
 234
 235 /*! @function withAddress
 236     @abstract Create an IOMemoryDescriptor to describe one virtual range of the specified map.
 237     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the specified map.
 238     @param address The virtual address of the first byte in the memory.
 239     @param withLength The length of memory.
 240     @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.
 241     @param withTask The task the virtual ranges are mapped into.
 242     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 243
 244     static IOMemoryDescriptor * withAddress(vm_address_t address,
 245                                             IOByteCount  withLength,
 246                                             IODirection  withDirection,
 247                                             task_t       withTask);
 248
 249 /*! @function withPhysicalAddress
 250     @abstract Create an IOMemoryDescriptor to describe one physical range.
 251     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single physical memory range.
 252     @param address The physical address of the first byte in the memory.
 253     @param withLength The length of memory.
 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     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 256
 257     static IOMemoryDescriptor * withPhysicalAddress(
 258                                 IOPhysicalAddress       address,
 259                                 IOByteCount             withLength,
 260                                 IODirection             withDirection );
 261
 262 /*! @function withRanges
 263     @abstract Create an IOMemoryDescriptor to describe one or more virtual ranges.
 264     @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.
 265     @param ranges An array of IOVirtualRange structures which specify the virtual ranges in the specified map which make up the memory to be described.
 266     @param withCount The member count of the ranges array.
 267     @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.
 268     @param withTask The task each of the virtual ranges are mapped into.
 269     @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.
 270     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 271
 272      static IOMemoryDescriptor * withRanges(IOVirtualRange * ranges,
 273                                             UInt32           withCount,
 274                                             IODirection      withDirection,
 275                                             task_t           withTask,
 276                                             bool             asReference = false);
 277
 278 /*! @function withAddressRange
 279     @abstract Create an IOMemoryDescriptor to describe one virtual range of the specified map.
 280     @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the specified map. Note that unlike IOMemoryDescriptor::withAddress(), kernel_task memory must be explicitly prepared when passed to this api.
 281     @param address The virtual address of the first byte in the memory.
 282     @param withLength The length of memory.
 283     @param options
 284         kIOMemoryDirectionMask (options:direction)      This nibble indicates the I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 285     @param task The task the virtual ranges are mapped into. Note that unlike IOMemoryDescriptor::withAddress(), kernel_task memory must be explicitly prepared when passed to this api.
 286     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 287
 288     static IOMemoryDescriptor * withAddressRange(
 289                                         mach_vm_address_t address,
 290                                         mach_vm_size_t    length,
 291                                         IOOptionBits      options,
 292                                         task_t            task);
 293
 294 /*! @function withAddressRanges
 295     @abstract Create an IOMemoryDescriptor to describe one or more virtual ranges.
 296     @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. Note that unlike IOMemoryDescriptor::withAddress(), kernel_task memory must be explicitly prepared when passed to this api.
 297     @param ranges An array of IOAddressRange structures which specify the virtual ranges in the specified map which make up the memory to be described. IOAddressRange is the 64bit version of IOVirtualRange.
 298     @param rangeCount The member count of the ranges array.
 299     @param options
 300         kIOMemoryDirectionMask (options:direction)      This nibble indicates the I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 301         kIOMemoryAsReference    For options:type = Virtual or Physical this indicate that the memory descriptor need not copy the ranges array into local memory.  This is an optimisation to try to minimise unnecessary allocations.
 302     @param task The task each of the virtual ranges are mapped into. Note that unlike IOMemoryDescriptor::withAddress(), kernel_task memory must be explicitly prepared when passed to this api.
 303     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 304
 305     static IOMemoryDescriptor * withAddressRanges(
 306                                         IOAddressRange * ranges,
 307                                         UInt32           rangeCount,
 308                                         IOOptionBits     options,
 309                                         task_t           withTask);
 310
 311 /*! @function withOptions
 312     @abstract Master initialiser for all variants of memory descriptors.
 313     @discussion This method creates and initializes an IOMemoryDescriptor for memory it has three main variants: Virtual, Physical & mach UPL.  These variants are selected with the options parameter, see below.  This memory descriptor needs to be prepared before it can be used to extract data from the memory described.  However we temporarily have setup a mechanism that automatically prepares kernel_task memory descriptors at creation time.
 314
 315
 316     @param buffers A pointer to an array of IOVirtualRanges or IOPhysicalRanges if the options:type is Virtual or Physical.  For type UPL it is a upl_t returned by the mach/memory_object_types.h apis, primarily used internally by the UBC.
 317
 318     @param count options:type = Virtual or Physical count contains a count of the number of entires in the buffers array.  For options:type = UPL this field contains a total length.
 319
 320     @param offset Only used when options:type = UPL, in which case this field contains an offset for the memory within the buffers upl.
 321
 322     @param task Only used options:type = Virtual, The task each of the virtual ranges are mapped into.
 323
 324     @param options
 325         kIOMemoryDirectionMask (options:direction)      This nibble indicates the I/O direction to be associated with the descriptor, which may affect the operation of the prepare and complete methods on some architectures.
 326         kIOMemoryTypeMask (options:type)        kIOMemoryTypeVirtual, kIOMemoryTypePhysical, kIOMemoryTypeUPL Indicates that what type of memory basic memory descriptor to use.  This sub-field also controls the interpretation of the buffers, count, offset & task parameters.
 327         kIOMemoryAsReference    For options:type = Virtual or Physical this indicate that the memory descriptor need not copy the ranges array into local memory.  This is an optimisation to try to minimise unnecessary allocations.
 328         kIOMemoryBufferPageable Only used by the IOBufferMemoryDescriptor as an indication that the kernel virtual memory is in fact pageable and we need to use the kernel pageable submap rather than the default map.
 329         kIOMemoryNoAutoPrepare  Indicates that the temporary AutoPrepare of kernel_task memory should not be performed.
 330
 331     @param mapper Which IOMapper should be used to map the in-memory physical addresses into I/O space addresses.  Defaults to 0 which indicates that the system mapper is to be used, if present.
 332
 333     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 334
 335     static IOMemoryDescriptor *withOptions(void *       buffers,
 336                                            UInt32       count,
 337                                            UInt32       offset,
 338                                            task_t       task,
 339                                            IOOptionBits options,
 340                                            IOMapper *   mapper = kIOMapperSystem);
 341
 342 /*! @function withPhysicalRanges
 343     @abstract Create an IOMemoryDescriptor to describe one or more physical ranges.
 344     @discussion  This method creates and initializes an IOMemoryDescriptor for memory consisting of an array of physical memory ranges.
 345     @param ranges An array of IOPhysicalRange structures which specify the physical ranges which make up the memory to be described.
 346     @param withCount The member count of the ranges array.
 347     @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.
 348     @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.
 349     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 350
 351     static IOMemoryDescriptor * withPhysicalRanges(
 352                                             IOPhysicalRange *   ranges,
 353                                             UInt32              withCount,
 354                                             IODirection         withDirection,
 355                                             bool                asReference = false);
 356
 357 /*! @function withSubRange
 358     @abstract Create an IOMemoryDescriptor to describe a subrange of an existing descriptor.
 359     @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.
 360     @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.
 361     @param offset A byte offset into the parent memory descriptor's memory.
 362     @param length The length of the subrange.
 363     @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.
 364     @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
 365
 366     static IOMemoryDescriptor * withSubRange(IOMemoryDescriptor *of,
 367                                              IOByteCount offset,
 368                                              IOByteCount length,
 369                                              IODirection withDirection);
 370
 371 /*! @function withPersistentMemoryDescriptor
 372     @abstract Copy constructor that generates a new memory descriptor if the backing memory for the same task's virtual address and length has changed.
 373     @discussion If the original memory descriptor's address and length is still backed by the same real memory, i.e. the user hasn't deallocated and the reallocated memory at the same address then the original memory descriptor is returned with a additional reference.  Otherwise we build a totally new memory descriptor with the same characteristics as the previous one but with a new view of the vm.  Note not legal to call this function with anything except an IOGeneralMemoryDescriptor that was created with the kIOMemoryPersistent option.
 374     @param originalMD The memory descriptor to be duplicated.
 375     @result Either the original memory descriptor with an additional retain or a new memory descriptor, 0 for a bad original memory descriptor or some other resource shortage. */
 376     static IOMemoryDescriptor *
 377         withPersistentMemoryDescriptor(IOMemoryDescriptor *originalMD);
 378
 379 /*! @function initWithAddress
 380     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one virtual range of the kernel task.
 381     @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.
 382     @param address The virtual address of the first byte in the memory.
 383     @param withLength The length of memory.
 384     @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.
 385     @result true on success, false on failure. */
 386
 387     virtual bool initWithAddress(void *       address,
 388                                  IOByteCount  withLength,
 389                                  IODirection  withDirection) = 0;
 390
 391 /*! @function initWithAddress
 392     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one virtual range of the specified map.
 393     @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.
 394     @param address The virtual address of the first byte in the memory.
 395     @param withLength The length of memory.
 396     @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.
 397     @param withTask The task the virtual ranges are mapped into.
 398     @result true on success, false on failure. */
 399
 400     virtual bool initWithAddress(vm_address_t address,
 401                                  IOByteCount  withLength,
 402                                  IODirection  withDirection,
 403                                  task_t       withTask) = 0;
 404
 405 /*! @function initWithPhysicalAddress
 406     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one physical range.
 407     @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.
 408     @param address The physical address of the first byte in the memory.
 409     @param withLength The length of memory.
 410     @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.
 411     @result true on success, false on failure. */
 412
 413     virtual bool initWithPhysicalAddress(
 414                                  IOPhysicalAddress      address,
 415                                  IOByteCount            withLength,
 416                                  IODirection            withDirection ) = 0;
 417
 418 /*! @function initWithRanges
 419     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one or more virtual ranges.
 420     @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.
 421     @param ranges An array of IOVirtualRange structures which specify the virtual ranges in the specified map which make up the memory to be described.
 422     @param withCount The member count of the ranges array.
 423     @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.
 424     @param withTask The task each of the virtual ranges are mapped into.
 425     @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.
 426     @result true on success, false on failure. */
 427
 428     virtual bool initWithRanges(IOVirtualRange * ranges,
 429                                 UInt32           withCount,
 430                                 IODirection      withDirection,
 431                                 task_t           withTask,
 432                                 bool             asReference = false) = 0;
 433
 434 /*! @function initWithPhysicalRanges
 435     @abstract Initialize or reinitialize an IOMemoryDescriptor to describe one or more physical ranges.
 436     @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.
 437     @param ranges An array of IOPhysicalRange structures which specify the physical ranges which make up the memory to be described.
 438     @param withCount The member count of the ranges array.
 439     @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.
 440     @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.
 441     @result true on success, false on failure. */
 442
 443     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 444                                         UInt32           withCount,
 445                                         IODirection      withDirection,
 446                                         bool             asReference = false) = 0;
 447
 448 /*! @function getDirection
 449     @abstract Accessor to get the direction the memory descriptor was created with.
 450     @discussion This method returns the direction the memory descriptor was created with.
 451     @result The direction. */
 452
 453     virtual IODirection getDirection() const;
 454
 455 /*! @function getLength
 456     @abstract Accessor to get the length of the memory descriptor (over all its ranges).
 457     @discussion This method returns the total length of the memory described by the descriptor, ie. the sum of its ranges' lengths.
 458     @result The byte count. */
 459
 460     virtual IOByteCount getLength() const;
 461
 462 /*! @function setTag
 463     @abstract Set the tag for the memory descriptor.
 464     @discussion This method sets the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
 465     @param tag The tag. */
 466
 467     virtual void setTag( IOOptionBits tag );
 468
 469 /*! @function getTag
 470     @abstract Accessor to the retrieve the tag for the memory descriptor.
 471     @discussion This method returns the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
 472     @result The tag. */
 473
 474     virtual IOOptionBits getTag( void );
 475
 476 /*! @function readBytes
 477     @abstract Copy data from the memory descriptor's buffer to the specified buffer.
 478     @discussion This method copies data from the memory descriptor's memory at the given offset, to the caller's buffer.  The memory descriptor MUST have the kIODirectionOut direcction bit set  and be prepared.  kIODirectionOut means that this memory descriptor will be output to an external device, so readBytes is used to get memory into a local buffer for a PIO transfer to the device.
 479     @param offset A byte offset into the memory descriptor's memory.
 480     @param bytes The caller supplied buffer to copy the data to.
 481     @param withLength The length of the data to copy.
 482     @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. */
 483
 484     virtual IOByteCount readBytes(IOByteCount offset,
 485                                 void * bytes, IOByteCount withLength);
 486
 487 /*! @function writeBytes
 488     @abstract Copy data to the memory descriptor's buffer from the specified buffer.
 489     @discussion This method copies data to the memory descriptor's memory at the given offset, from the caller's buffer.  The memory descriptor MUST have the kIODirectionIn direcction bit set  and be prepared.  kIODirectionIn means that this memory descriptor will be input from an external device, so writeBytes is used to write memory into the descriptor for PIO drivers.
 490     @param offset A byte offset into the memory descriptor's memory.
 491     @param bytes The caller supplied buffer to copy the data from.
 492     @param withLength The length of the data to copy.
 493     @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. */
 494
 495     virtual IOByteCount writeBytes(IOByteCount offset,
 496                                 const void * bytes, IOByteCount withLength);
 497
 498 /*! @function getPhysicalSegment
 499     @abstract Break a memory descriptor into its physically contiguous segments.
 500     @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.
 501     @param offset A byte offset into the memory whose physical address to return.
 502     @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
 503     @result A physical address, or zero if the offset is beyond the length of the memory. */
 504
 505     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 506                                                  IOByteCount * length) = 0;
 507
 508 /*! @function getPhysicalAddress
 509     @abstract Return the physical address of the first byte in the memory.
 510     @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.
 511     @result A physical address. */
 512
 513     /* inline */ IOPhysicalAddress getPhysicalAddress();
 514         /* { return( getPhysicalSegment( 0, 0 )); } */
 515
 516     /* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
 517     /* DEPRECATED */ virtual void * getVirtualSegment(IOByteCount offset,
 518     /* DEPRECATED */                                    IOByteCount * length) = 0;
 519     /* DEPRECATED */ /* USE INSTEAD: map(), readBytes(), writeBytes() */
 520
 521 /*! @function prepare
 522     @abstract Prepare the memory for an I/O transfer.
 523     @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.  Note that the prepare call is not thread safe and it is expected that the client will more easily be able to guarantee single threading a particular memory descriptor.
 524     @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
 525     @result An IOReturn code. */
 526
 527     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) = 0;
 528
 529 /*! @function complete
 530     @abstract Complete processing of the memory after an I/O transfer finishes.
 531     @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.  In 10.3 or greater systems the direction argument to complete is not longer respected.  The direction is totally determined at prepare() time.
 532     @param forDirection DEPRECATED The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
 533     @result An IOReturn code. */
 534
 535     virtual IOReturn complete(IODirection forDirection = kIODirectionNone) = 0;
 536
 537     /*
 538      * Mapping functions.
 539      */
 540
 541 /*! @function createMappingInTask
 542     @abstract Maps a IOMemoryDescriptor into a task.
 543     @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.
 544     @param intoTask Sets the target task for the mapping. Pass kernel_task for the kernel address space.
 545     @param atAddress If a placed mapping is requested, atAddress specifies its address, and the kIOMapAnywhere should not be set. Otherwise, atAddress is ignored.
 546     @param options Mapping options are defined in IOTypes.h,<br>
 547         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>
 548         kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
 549         kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
 550         kIOMapReadOnly to allow only read only accesses to the memory - writes will cause and access fault.<br>
 551         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>
 552         kIOMapUnique allows a special kind of mapping to be created that may be used with the IOMemoryMap::redirect() API. These mappings will not be shared as is the default - there will always be a unique mapping created for the caller, not an existing mapping with an extra reference.<br>
 553     @param offset Is a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default to map all the memory.
 554     @param length Is the length of the mapping requested for a subset of the IOMemoryDescriptor. Zero is the default to map all the memory.
 555     @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. */
 556
 557     IOMemoryMap *       createMappingInTask(
 558         task_t                  intoTask,
 559         mach_vm_address_t       atAddress,
 560         IOOptionBits            options,
 561         mach_vm_size_t          offset = 0,
 562         mach_vm_size_t          length = 0 );
 563
 564 /*! @function map
 565     @abstract Maps a IOMemoryDescriptor into a task - deprecated, only safe for 32 bit tasks. Use createMappingInTask instead.
 566     @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.
 567     @param intoTask Sets the target task for the mapping. Pass kernel_task for the kernel address space.
 568     @param atAddress If a placed mapping is requested, atAddress specifies its address, and the kIOMapAnywhere should not be set. Otherwise, atAddress is ignored.
 569     @param options Mapping options are defined in IOTypes.h,<br>
 570         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>
 571         kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
 572         kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
 573         kIOMapReadOnly to allow only read only accesses to the memory - writes will cause and access fault.<br>
 574         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>
 575         kIOMapUnique allows a special kind of mapping to be created that may be used with the IOMemoryMap::redirect() API. These mappings will not be shared as is the default - there will always be a unique mapping created for the caller, not an existing mapping with an extra reference.<br>
 576     @param offset Is a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default to map all the memory.
 577     @param length Is the length of the mapping requested for a subset of the IOMemoryDescriptor. Zero is the default to map all the memory.
 578     @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. */
 579
 580     virtual IOMemoryMap *       map(
 581         task_t          intoTask,
 582         IOVirtualAddress        atAddress,
 583         IOOptionBits            options,
 584         IOByteCount             offset = 0,
 585         IOByteCount             length = 0 );
 586
 587
 588 /*! @function map
 589     @abstract Maps a IOMemoryDescriptor into the kernel map.
 590     @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 createMappingInTask method for further details.
 591     @param options Mapping options as in the full version of the createMappingInTask method, with kIOMapAnywhere assumed.
 592     @result See the full version of the createMappingInTask method. */
 593
 594     virtual IOMemoryMap *       map(
 595         IOOptionBits            options = 0 );
 596
 597 /*! @function setMapping
 598     @abstract Establishes an already existing mapping.
 599     @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.
 600     @param task Address space in which the mapping exists.
 601     @param mapAddress Virtual address of the mapping.
 602     @param options Caching and read-only attributes of the mapping.
 603     @result A IOMemoryMap object created to represent the mapping. */
 604
 605     virtual IOMemoryMap *       setMapping(
 606         task_t          task,
 607         IOVirtualAddress        mapAddress,
 608         IOOptionBits            options = 0 );
 609
 610     // Following methods are private implementation
 611
 612     // make virtual
 613     IOReturn redirect( task_t safeTask, bool redirect );
 614
 615     IOReturn handleFault(
 616         void *                  pager,
 617         vm_map_t                addressMap,
 618         mach_vm_address_t       address,
 619         mach_vm_size_t          sourceOffset,
 620         mach_vm_size_t          length,
 621         IOOptionBits            options );
 622
 623 protected:
 624     virtual IOMemoryMap *       makeMapping(
 625         IOMemoryDescriptor *    owner,
 626         task_t                  intoTask,
 627         IOVirtualAddress        atAddress,
 628         IOOptionBits            options,
 629         IOByteCount             offset,
 630         IOByteCount             length );
 631
 632     virtual void                addMapping(
 633         IOMemoryMap *           mapping );
 634
 635     virtual void                removeMapping(
 636         IOMemoryMap *           mapping );
 637
 638     virtual IOReturn doMap(
 639         vm_map_t                addressMap,
 640         IOVirtualAddress *      atAddress,
 641         IOOptionBits            options,
 642         IOByteCount             sourceOffset = 0,
 643         IOByteCount             length = 0 );
 644
 645     virtual IOReturn doUnmap(
 646         vm_map_t                addressMap,
 647         IOVirtualAddress        logical,
 648         IOByteCount             length );
 649 };
 650
 651 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 652
 653 /*! @class IOMemoryMap : public OSObject
 654     @abstract An abstract base class defining common methods for describing a memory mapping.
 655     @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. */
 656
 657 class IOMemoryMap : public OSObject
 658 {
 659     OSDeclareAbstractStructors(IOMemoryMap)
 660
 661 public:
 662 /*! @function getVirtualAddress
 663     @abstract Accessor to the virtual address of the first byte in the mapping.
 664     @discussion This method returns the virtual address of the first byte in the mapping.
 665     @result A virtual address. */
 666
 667     virtual IOVirtualAddress    getVirtualAddress() = 0;
 668
 669 /*! @function getPhysicalSegment
 670     @abstract Break a mapping into its physically contiguous segments.
 671     @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.
 672     @param offset A byte offset into the mapping whose physical address to return.
 673     @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
 674     @result A physical address, or zero if the offset is beyond the length of the mapping. */
 675
 676     virtual IOPhysicalAddress   getPhysicalSegment(IOByteCount offset,
 677                                                    IOByteCount * length) = 0;
 678
 679 /*! @function getPhysicalAddress
 680     @abstract Return the physical address of the first byte in the mapping.
 681     @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.
 682     @result A physical address. */
 683
 684     /* inline */ IOPhysicalAddress getPhysicalAddress();
 685         /* { return( getPhysicalSegment( 0, 0 )); } */
 686
 687 /*! @function getLength
 688     @abstract Accessor to the length of the mapping.
 689     @discussion This method returns the length of the mapping.
 690     @result A byte count. */
 691
 692     virtual IOByteCount         getLength() = 0;
 693
 694 /*! @function getAddressTask
 695     @abstract Accessor to the task of the mapping.
 696     @discussion This method returns the mach task the mapping exists in.
 697     @result A mach task_t. */
 698
 699     virtual task_t              getAddressTask() = 0;
 700
 701 /*! @function getMemoryDescriptor
 702     @abstract Accessor to the IOMemoryDescriptor the mapping was created from.
 703     @discussion This method returns the IOMemoryDescriptor the mapping was created from.
 704     @result An IOMemoryDescriptor reference, which is valid while the IOMemoryMap object is retained. It should not be released by the caller. */
 705
 706     virtual IOMemoryDescriptor * getMemoryDescriptor() = 0;
 707
 708 /*! @function getMapOptions
 709     @abstract Accessor to the options the mapping was created with.
 710     @discussion This method returns the options to IOMemoryDescriptor::map the mapping was created with.
 711     @result Options for the mapping, including cache settings. */
 712
 713     virtual IOOptionBits        getMapOptions() = 0;
 714
 715 /*! @function unmap
 716     @abstract Force the IOMemoryMap to unmap, without destroying the object.
 717     @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.
 718     @result An IOReturn code. */
 719
 720     virtual IOReturn            unmap() = 0;
 721
 722     virtual void                taskDied() = 0;
 723
 724 /*! @function redirect
 725     @abstract Replace the memory mapped in a process with new backing memory.
 726     @discussion An IOMemoryMap created with the kIOMapUnique option to IOMemoryDescriptor::map() can remapped to a new IOMemoryDescriptor backing object. If the new IOMemoryDescriptor is specified as NULL, client access to the memory map is blocked until a new backing object has been set. By blocking access and copying data, the caller can create atomic copies of the memory while the client is potentially reading or writing the memory.
 727     @param newBackingMemory The IOMemoryDescriptor that represents the physical memory that is to be now mapped in the virtual range the IOMemoryMap represents. If newBackingMemory is NULL, any access to the mapping will hang (in vm_fault()) until access has been restored by a new call to redirect() with non-NULL newBackingMemory argument.
 728     @param options Mapping options are defined in IOTypes.h, and are documented in IOMemoryDescriptor::map()
 729     @param offset As with IOMemoryDescriptor::map(), a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default.
 730     @result An IOReturn code. */
 731
 732     virtual IOReturn            redirect(IOMemoryDescriptor * newBackingMemory,
 733                                          IOOptionBits         options,
 734                                          IOByteCount          offset = 0) = 0;
 735
 736     virtual IOReturn            redirect(IOMemoryDescriptor * newBackingMemory,
 737                                          IOOptionBits         options,
 738                                          mach_vm_size_t       offset = 0) = 0;
 739
 740     virtual mach_vm_address_t   getAddress() = 0;
 741     virtual mach_vm_size_t      getSize() = 0;
 742 };
 743
 744 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 745
 746 // The following classes are private implementation of IOMemoryDescriptor - they
 747 // should not be referenced directly, just through the public API's in the
 748 // IOMemoryDescriptor class. For example, an IOGeneralMemoryDescriptor instance
 749 // might be created by IOMemoryDescriptor::withAddress(), but there should be
 750 // no need to reference as anything but a generic IOMemoryDescriptor *.
 751
 752 class IOGeneralMemoryDescriptor : public IOMemoryDescriptor
 753 {
 754     OSDeclareDefaultStructors(IOGeneralMemoryDescriptor);
 755
 756 public:
 757     union Ranges {
 758         IOVirtualRange   *v;
 759         IOAddressRange   *v64;
 760         IOPhysicalRange  *p;
 761         void             *uio;
 762     };
 763 protected:
 764     Ranges              _ranges;
 765     unsigned            _rangesCount;       /* number of address ranges in list */
 766     bool                _rangesIsAllocated; /* is list allocated by us? */
 767
 768     task_t              _task;               /* task where all ranges are mapped to */
 769
 770     union {
 771         IOVirtualRange  v;
 772         IOPhysicalRange p;
 773     }                   _singleRange;      /* storage space for a single range */
 774
 775     unsigned            _wireCount;        /* number of outstanding wires */
 776
 777     /* DEPRECATED */ vm_address_t _cachedVirtualAddress;  /* a cached virtual-to-physical */
 778
 779     /* DEPRECATED */ IOPhysicalAddress  _cachedPhysicalAddress;
 780
 781     bool                _initialized;      /* has superclass been initialized? */
 782
 783     virtual void free();
 784
 785     virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
 786
 787 private:
 788
 789     /* DEPRECATED */ virtual void setPosition(IOByteCount position);
 790     /* DEPRECATED */ virtual void mapIntoKernel(unsigned rangeIndex);
 791     /* DEPRECATED */ virtual void unmapFromKernel();
 792
 793     // Internal APIs may be made virtual at some time in the future.
 794     IOReturn wireVirtual(IODirection forDirection);
 795     void *createNamedEntry();
 796
 797     // Internal
 798     OSData *        _memoryEntries;
 799     unsigned int    _pages;
 800     ppnum_t         _highestPage;
 801     uint32_t        __iomd_reservedA;
 802     uint32_t        __iomd_reservedB;
 803
 804     IOLock *        _prepareLock;
 805
 806 public:
 807     /*
 808      * IOMemoryDescriptor required methods
 809      */
 810
 811     // Master initaliser
 812     virtual bool initWithOptions(void *         buffers,
 813                                  UInt32         count,
 814                                  UInt32         offset,
 815                                  task_t         task,
 816                                  IOOptionBits   options,
 817                                  IOMapper *     mapper = kIOMapperSystem);
 818
 819     // Secondary initialisers
 820     virtual bool initWithAddress(void *         address,
 821                                  IOByteCount    withLength,
 822                                  IODirection    withDirection);
 823
 824     virtual bool initWithAddress(vm_address_t   address,
 825                                  IOByteCount    withLength,
 826                                  IODirection    withDirection,
 827                                  task_t         withTask);
 828
 829     virtual bool initWithPhysicalAddress(
 830                                  IOPhysicalAddress      address,
 831                                  IOByteCount            withLength,
 832                                  IODirection            withDirection );
 833
 834     virtual bool initWithRanges(        IOVirtualRange * ranges,
 835                                         UInt32           withCount,
 836                                         IODirection      withDirection,
 837                                         task_t           withTask,
 838                                         bool             asReference = false);
 839
 840     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 841                                         UInt32           withCount,
 842                                         IODirection      withDirection,
 843                                         bool             asReference = false);
 844
 845     virtual addr64_t getPhysicalSegment64( IOByteCount offset,
 846                                             IOByteCount * length );
 847
 848     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 849                                                  IOByteCount * length);
 850
 851     virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
 852                                                IOByteCount * length);
 853
 854     /* DEPRECATED */ virtual void * getVirtualSegment(IOByteCount offset,
 855     /* DEPRECATED */                                    IOByteCount * length);
 856
 857     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);
 858
 859     virtual IOReturn complete(IODirection forDirection = kIODirectionNone);
 860
 861     virtual IOReturn doMap(
 862         vm_map_t                addressMap,
 863         IOVirtualAddress *      atAddress,
 864         IOOptionBits            options,
 865         IOByteCount             sourceOffset = 0,
 866         IOByteCount             length = 0 );
 867
 868     virtual IOReturn doUnmap(
 869         vm_map_t                addressMap,
 870         IOVirtualAddress        logical,
 871         IOByteCount             length );
 872
 873     virtual bool serialize(OSSerialize *s) const;
 874
 875     // Factory method for cloning a persistent IOMD, see IOMemoryDescriptor
 876     static IOMemoryDescriptor *
 877         withPersistentMemoryDescriptor(IOGeneralMemoryDescriptor *originalMD);
 878
 879 };
 880
 881 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 882
 883 class IOSubMemoryDescriptor : public IOMemoryDescriptor
 884 {
 885     friend class IOMemoryDescriptor;
 886
 887     OSDeclareDefaultStructors(IOSubMemoryDescriptor);
 888
 889 protected:
 890     IOMemoryDescriptor * _parent;
 891     IOByteCount          _start;
 892
 893     virtual void free();
 894
 895     virtual bool initWithAddress(void *       address,
 896                                  IOByteCount    withLength,
 897                                  IODirection  withDirection);
 898
 899     virtual bool initWithAddress(vm_address_t address,
 900                                  IOByteCount    withLength,
 901                                  IODirection  withDirection,
 902                                  task_t       withTask);
 903
 904     virtual bool initWithPhysicalAddress(
 905                                  IOPhysicalAddress      address,
 906                                  IOByteCount            withLength,
 907                                  IODirection            withDirection );
 908
 909     virtual bool initWithRanges(        IOVirtualRange * ranges,
 910                                         UInt32           withCount,
 911                                         IODirection      withDirection,
 912                                         task_t           withTask,
 913                                         bool             asReference = false);
 914
 915     virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
 916                                         UInt32           withCount,
 917                                         IODirection      withDirection,
 918                                         bool             asReference = false);
 919
 920     IOMemoryDescriptor::withAddress;
 921     IOMemoryDescriptor::withPhysicalAddress;
 922     IOMemoryDescriptor::withPhysicalRanges;
 923     IOMemoryDescriptor::withRanges;
 924     IOMemoryDescriptor::withSubRange;
 925
 926     // used by IODMACommand
 927     virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
 928
 929 public:
 930     /*
 931      * Initialize or reinitialize an IOSubMemoryDescriptor to describe
 932      * a subrange of an existing descriptor.
 933      *
 934      * An IOSubMemoryDescriptor can be re-used by calling initSubRange
 935      * again on an existing instance -- note that this behavior is not
 936      * commonly supported in other IOKit classes, although it is here.
 937      */
 938     virtual bool initSubRange( IOMemoryDescriptor * parent,
 939                                 IOByteCount offset, IOByteCount length,
 940                                 IODirection withDirection );
 941
 942     /*
 943      * IOMemoryDescriptor required methods
 944      */
 945
 946     virtual addr64_t getPhysicalSegment64( IOByteCount offset,
 947                                             IOByteCount * length );
 948
 949     virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
 950                                                  IOByteCount * length);
 951
 952     virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
 953                                                IOByteCount * length);
 954
 955     virtual IOByteCount readBytes(IOByteCount offset,
 956                                 void * bytes, IOByteCount withLength);
 957
 958     virtual IOByteCount writeBytes(IOByteCount offset,
 959                                 const void * bytes, IOByteCount withLength);
 960
 961     virtual void * getVirtualSegment(IOByteCount offset,
 962                                         IOByteCount * length);
 963
 964     virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);
 965
 966     virtual IOReturn complete(IODirection forDirection = kIODirectionNone);
 967
 968     // make virtual
 969     IOReturn redirect( task_t safeTask, bool redirect );
 970
 971     virtual bool serialize(OSSerialize *s) const;
 972
 973     virtual IOReturn setPurgeable( IOOptionBits newState,
 974                                     IOOptionBits * oldState );
 975     virtual IOReturn performOperation( IOOptionBits options,
 976                                         IOByteCount offset, IOByteCount length );
 977
 978 protected:
 979     virtual IOMemoryMap *       makeMapping(
 980         IOMemoryDescriptor *    owner,
 981         task_t                  intoTask,
 982         IOVirtualAddress        atAddress,
 983         IOOptionBits            options,
 984         IOByteCount             offset,
 985         IOByteCount             length );
 986
 987     virtual IOReturn doMap(
 988        vm_map_t                addressMap,
 989        IOVirtualAddress *      atAddress,
 990        IOOptionBits            options,
 991        IOByteCount             sourceOffset = 0,
 992        IOByteCount             length = 0 );
 993 };
 994
 995 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 996
 997 #endif /* !_IOMEMORYDESCRIPTOR_H */