xref: /xnu-11417.140.69/iokit/IOKit/IOMemoryDescriptor.h (revision 43a90889846e00bfb5cf1d255cdc0a701a1e05a4)
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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++/OSPtr.h>
36 #include <libkern/c++/OSContainers.h>
37 #include <DriverKit/IOMemoryDescriptor.h>
38 #include <DriverKit/IOMemoryMap.h>
39 #ifdef XNU_KERNEL_PRIVATE
40 #include <IOKit/IOKitDebug.h>
41 #endif
42 
43 #include <mach/memory_object_types.h>
44 
45 class IOMemoryDescriptor;
46 class IOMemoryMap;
47 class IOMapper;
48 class IOService;
49 class IODMACommand;
50 class _IOMemoryDescriptorMixedData;
51 
52 /*
53  * Direction of transfer, with respect to the described memory.
54  */
55 #ifdef __LP64__
56 enum
57 #else /* !__LP64__ */
58 enum IODirection
59 #endif /* !__LP64__ */
60 {
61 	kIODirectionNone  = 0x0,//                    same as VM_PROT_NONE
62 	kIODirectionIn    = 0x1,// User land 'read',  same as VM_PROT_READ
63 	kIODirectionOut   = 0x2,// User land 'write', same as VM_PROT_WRITE
64 	kIODirectionOutIn = kIODirectionOut | kIODirectionIn,
65 	kIODirectionInOut = kIODirectionIn  | kIODirectionOut,
66 
67 	// these flags are valid for the prepare() method only
68 	kIODirectionPrepareToPhys32   = 0x00000004,
69 	kIODirectionPrepareNoFault    = 0x00000008,
70 	kIODirectionPrepareReserved1  = 0x00000010,
71 #define IODIRECTIONPREPARENONCOHERENTDEFINED    1
72 	kIODirectionPrepareNonCoherent = 0x00000020,
73 #if KERNEL_PRIVATE
74 #define IODIRECTIONPREPAREAVOIDTHROTTLING       1
75 	kIODirectionPrepareAvoidThrottling = 0x00000100,
76 #endif
77 
78 	// these flags are valid for the complete() method only
79 #define IODIRECTIONCOMPLETEWITHERRORDEFINED             1
80 	kIODirectionCompleteWithError = 0x00000040,
81 #define IODIRECTIONCOMPLETEWITHDATAVALIDDEFINED 1
82 	kIODirectionCompleteWithDataValid = 0x00000080,
83 };
84 
85 #ifdef __LP64__
86 typedef IOOptionBits IODirection;
87 #endif /* __LP64__ */
88 
89 /*
90  * IOOptionBits used in the withOptions variant
91  */
92 enum {
93 	kIOMemoryDirectionMask      = 0x00000007,
94 #ifdef XNU_KERNEL_PRIVATE
95 	kIOMemoryAutoPrepare        = 0x00000008,// Shared with Buffer MD
96 #endif
97 
98 	kIOMemoryTypeVirtual        = 0x00000010,
99 	kIOMemoryTypePhysical       = 0x00000020,
100 	kIOMemoryTypeUPL            = 0x00000030,
101 	kIOMemoryTypePersistentMD   = 0x00000040,// Persistent Memory Descriptor
102 	kIOMemoryTypeUIO            = 0x00000050,
103 #ifdef __LP64__
104 	kIOMemoryTypeVirtual64      = kIOMemoryTypeVirtual,
105 	kIOMemoryTypePhysical64     = kIOMemoryTypePhysical,
106 #else /* !__LP64__ */
107 	kIOMemoryTypeVirtual64      = 0x00000060,
108 	kIOMemoryTypePhysical64     = 0x00000070,
109 #endif /* !__LP64__ */
110 	kIOMemoryTypeMask           = 0x000000f0,
111 
112 	kIOMemoryAsReference        = 0x00000100,
113 	kIOMemoryBufferPageable     = 0x00000400,
114 	kIOMemoryMapperNone         = 0x00000800,// Shared with Buffer MD
115 	kIOMemoryHostOnly           = 0x00001000,// Never DMA accessible
116 #ifdef XNU_KERNEL_PRIVATE
117 	kIOMemoryRedirected         = 0x00004000,
118 	kIOMemoryPreparedReadOnly   = 0x00008000,
119 #endif
120 	kIOMemoryPersistent         = 0x00010000,
121 	kIOMemoryMapCopyOnWrite     = 0x00020000,
122 	kIOMemoryRemote             = 0x00040000,
123 	kIOMemoryThreadSafe         = 0x00100000,// Shared with Buffer MD
124 	kIOMemoryClearEncrypt       = 0x00200000,// Shared with Buffer MD
125 	kIOMemoryUseReserve         = 0x00800000,// Shared with Buffer MD
126 #define IOMEMORYUSERESERVEDEFINED       1
127 
128 #ifdef XNU_KERNEL_PRIVATE
129 	kIOMemoryBufferPurgeable    = 0x00400000,
130 	kIOMemoryBufferCacheMask    = 0x70000000,
131 	kIOMemoryBufferCacheShift   = 28,
132 #endif
133 };
134 
135 #define kIOMapperSystem ((IOMapper *) NULL)
136 
137 enum{
138 	kIOMemoryLedgerTagDefault       = VM_LEDGER_TAG_DEFAULT,
139 	kIOmemoryLedgerTagNetwork       = VM_LEDGER_TAG_NETWORK,
140 	kIOMemoryLedgerTagMedia         = VM_LEDGER_TAG_MEDIA,
141 	kIOMemoryLedgerTagGraphics      = VM_LEDGER_TAG_GRAPHICS,
142 	kIOMemoryLedgerTagNeural        = VM_LEDGER_TAG_NEURAL,
143 };
144 enum{
145 	kIOMemoryLedgerFlagNoFootprint  = VM_LEDGER_FLAG_NO_FOOTPRINT,
146 };
147 
148 enum{
149 	kIOMemoryPurgeableKeepCurrent = 1,
150 
151 	kIOMemoryPurgeableNonVolatile = 2,
152 	kIOMemoryPurgeableVolatile    = 3,
153 	kIOMemoryPurgeableEmpty       = 4,
154 
155 	// modifiers for kIOMemoryPurgeableVolatile behavior
156 	kIOMemoryPurgeableVolatileGroup0           = VM_VOLATILE_GROUP_0,
157 	kIOMemoryPurgeableVolatileGroup1           = VM_VOLATILE_GROUP_1,
158 	kIOMemoryPurgeableVolatileGroup2           = VM_VOLATILE_GROUP_2,
159 	kIOMemoryPurgeableVolatileGroup3           = VM_VOLATILE_GROUP_3,
160 	kIOMemoryPurgeableVolatileGroup4           = VM_VOLATILE_GROUP_4,
161 	kIOMemoryPurgeableVolatileGroup5           = VM_VOLATILE_GROUP_5,
162 	kIOMemoryPurgeableVolatileGroup6           = VM_VOLATILE_GROUP_6,
163 	kIOMemoryPurgeableVolatileGroup7           = VM_VOLATILE_GROUP_7,
164 	kIOMemoryPurgeableVolatileBehaviorFifo     = VM_PURGABLE_BEHAVIOR_FIFO,
165 	kIOMemoryPurgeableVolatileBehaviorLifo     = VM_PURGABLE_BEHAVIOR_LIFO,
166 	kIOMemoryPurgeableVolatileOrderingObsolete = VM_PURGABLE_ORDERING_OBSOLETE,
167 	kIOMemoryPurgeableVolatileOrderingNormal   = VM_PURGABLE_ORDERING_NORMAL,
168 	kIOMemoryPurgeableFaultOnAccess            = VM_PURGABLE_DEBUG_FAULT,
169 };
170 enum{
171 	kIOMemoryIncoherentIOFlush   = 1,
172 	kIOMemoryIncoherentIOStore   = 2,
173 
174 	kIOMemoryClearEncrypted      = 50,
175 	kIOMemorySetEncrypted        = 51,
176 };
177 
178 #define IOMEMORYDESCRIPTOR_SUPPORTS_DMACOMMAND  1
179 
180 struct IODMAMapSpecification {
181 	uint64_t    alignment;
182 	IOService * device;
183 	uint32_t    options;
184 	uint8_t     numAddressBits;
185 	uint8_t     resvA[3];
186 	uint32_t    resvB[4];
187 };
188 
189 struct IODMAMapPageList {
190 	uint32_t                pageOffset;
191 	uint32_t                pageListCount;
192 	const upl_page_info_t * pageList;
193 };
194 
195 // mapOptions for iovmMapMemory
196 enum{
197 	kIODMAMapReadAccess           = 0x00000001,
198 	kIODMAMapWriteAccess          = 0x00000002,
199 	kIODMAMapPhysicallyContiguous = 0x00000010,
200 	kIODMAMapDeviceMemory         = 0x00000020,
201 	kIODMAMapPagingPath           = 0x00000040,
202 	kIODMAMapIdentityMap          = 0x00000080,
203 
204 	kIODMAMapPageListFullyOccupied = 0x00000100,
205 	kIODMAMapFixedAddress          = 0x00000200,
206 };
207 
208 // Options used by IOMapper. example IOMappers are DART and VT-d
209 enum {
210 	kIOMapperUncached      = 0x0001,
211 #ifdef KERNEL_PRIVATE
212 	kIOMapperTransient     = 0x0002,
213 #endif
214 };
215 
216 #ifdef KERNEL_PRIVATE
217 
218 // Used for dmaCommandOperation communications for IODMACommand and mappers
219 
220 enum  {
221 	kIOMDWalkSegments             = 0x01000000,
222 	kIOMDFirstSegment             = 1 | kIOMDWalkSegments,
223 	kIOMDGetCharacteristics       = 0x02000000,
224 	kIOMDGetCharacteristicsMapped = 1 | kIOMDGetCharacteristics,
225 	kIOMDDMAActive                = 0x03000000,
226 	kIOMDSetDMAActive             = 1 | kIOMDDMAActive,
227 	kIOMDSetDMAInactive           = kIOMDDMAActive,
228 	kIOMDAddDMAMapSpec            = 0x04000000,
229 	kIOMDDMAMap                   = 0x05000000,
230 	kIOMDDMAUnmap                 = 0x06000000,
231 	kIOMDDMACommandOperationMask  = 0xFF000000,
232 };
233 struct IOMDDMACharacteristics {
234 	UInt64 fLength;
235 	UInt32 fSGCount;
236 	UInt32 fPages;
237 	UInt32 fPageAlign;
238 	ppnum_t fHighestPage;
239 	IODirection fDirection;
240 	UInt8 fIsPrepared;
241 };
242 
243 struct IOMDDMAMapArgs {
244 	IOMapper            * fMapper;
245 	IODMACommand        * fCommand;
246 	IODMAMapSpecification fMapSpec;
247 	uint64_t              fOffset;
248 	uint64_t              fLength;
249 	uint64_t              fAlloc;
250 	uint64_t              fAllocLength;
251 };
252 
253 struct IOMDDMAWalkSegmentArgs {
254 	UInt64 fOffset;                 // Input/Output offset
255 	/* Output variables.
256 	 * Note to reader: fIOVMAddr is (sometimes?) a DART-mapped device address.
257 	 */
258 	UInt64 fIOVMAddr, fLength;
259 	UInt8 fMapped;                  // Input Variable, Require mapped IOVMA
260 	UInt64 fMappedBase;             // Input base of mapping
261 };
262 typedef UInt8 IOMDDMAWalkSegmentState[128];
263 
264 #endif /* KERNEL_PRIVATE */
265 
266 enum{
267 	kIOPreparationIDUnprepared = 0,
268 	kIOPreparationIDUnsupported = 1,
269 	kIOPreparationIDAlwaysPrepared = 2,
270 };
271 
272 #ifdef KERNEL_PRIVATE
273 #define kIODescriptorIDInvalid (0)
274 #endif
275 
276 #ifdef XNU_KERNEL_PRIVATE
277 struct IOMemoryReference;
278 #endif
279 
280 
281 /*! @class IOMemoryDescriptor : public OSObject
282  *   @abstract An abstract base class defining common methods for describing physical or virtual memory.
283  *   @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. */
284 
285 class IOMemoryDescriptor : public OSObject
286 {
287 	friend class IOMemoryMap;
288 	friend class IOMultiMemoryDescriptor;
289 
290 	OSDeclareDefaultStructorsWithDispatch(IOMemoryDescriptor);
291 
292 protected:
293 
294 /*! @var reserved
295  *   Reserved for future use.  (Internal use only)  */
296 	struct IOMemoryDescriptorReserved * reserved;
297 
298 protected:
299 	OSPtr<OSSet>        _mappings;
300 	IOOptionBits        _flags;
301 
302 
303 #ifdef XNU_KERNEL_PRIVATE
304 public:
305 	struct IOMemoryReference *  _memRef;
306 	vm_tag_t _kernelTag;
307 	vm_tag_t _userTag;
308 	int16_t _dmaReferences;
309 	uint16_t _internalFlags;
310 	kern_allocation_name_t _mapName;
311 protected:
312 #else /* XNU_KERNEL_PRIVATE */
313 	void *              __iomd_reserved5;
314 	uint16_t            __iomd_reserved1[4];
315 	uintptr_t           __iomd_reserved2;
316 #endif /* XNU_KERNEL_PRIVATE */
317 
318 	uint16_t            _iomapperOptions;
319 #ifdef __LP64__
320 	uint16_t            __iomd_reserved3[3];
321 #else
322 	uint16_t            __iomd_reserved3;
323 #endif
324 	uintptr_t           __iomd_reserved4;
325 
326 #ifndef __LP64__
327 	IODirection         _direction;    /* use _flags instead */
328 #endif /* !__LP64__ */
329 	IOByteCount         _length;       /* length of all ranges */
330 	IOOptionBits        _tag;
331 
332 public:
333 	typedef IOOptionBits DMACommandOps;
334 #ifndef __LP64__
335 	virtual IOPhysicalAddress getSourceSegment( IOByteCount offset,
336 	    IOByteCount * length ) APPLE_KEXT_DEPRECATED;
337 #endif /* !__LP64__ */
338 
339 /*! @function initWithOptions
340  *   @abstract Master initialiser for all variants of memory descriptors.  For a more complete description see IOMemoryDescriptor::withOptions.
341  *   @discussion Note this function can be used to re-init a previously created memory descriptor.
342  *   @result true on success, false on failure. */
343 	virtual bool initWithOptions(void *         buffers,
344 	    UInt32         count,
345 	    UInt32         offset,
346 	    task_t         task,
347 	    IOOptionBits   options,
348 	    IOMapper *     mapper = kIOMapperSystem);
349 
350 #ifndef __LP64__
351 	virtual addr64_t getPhysicalSegment64( IOByteCount offset,
352 	    IOByteCount * length ) APPLE_KEXT_DEPRECATED;                                 /* use getPhysicalSegment() and kIOMemoryMapperNone instead */
353 #endif /* !__LP64__ */
354 
355 /*! @function setPurgeable
356  *   @abstract Control the purgeable status of a memory descriptors memory.
357  *   @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.
358  *   @param newState - the desired new purgeable state of the memory:<br>
359  *   kIOMemoryPurgeableKeepCurrent - make no changes to the memory's purgeable state.<br>
360  *   kIOMemoryPurgeableVolatile    - make the memory volatile - the memory may be reclaimed by the VM system without saving its contents to backing store.<br>
361  *   kIOMemoryPurgeableNonVolatile - make the memory nonvolatile - the memory is treated as with usual allocations and must be saved to backing store if paged.<br>
362  *   kIOMemoryPurgeableEmpty       - make the memory volatile, and discard any pages allocated to it.
363  *   @param oldState - if non-NULL, the previous purgeable state of the memory is returned here:<br>
364  *   kIOMemoryPurgeableNonVolatile - the memory was nonvolatile.<br>
365  *   kIOMemoryPurgeableVolatile    - the memory was volatile but its content has not been discarded by the VM system.<br>
366  *   kIOMemoryPurgeableEmpty       - the memory was volatile and has been discarded by the VM system.<br>
367  *   @result An IOReturn code. */
368 
369 	virtual IOReturn setPurgeable( IOOptionBits newState,
370 	    IOOptionBits * oldState );
371 
372 /*! @function setOwnership
373  *   @abstract Control the ownership of a memory descriptors memory.
374  *   @discussion IOBufferMemoryDescriptor are owned by a specific task. The ownership of such a buffer may be controlled with setOwnership().
375  *   @param newOwner - the task to be the new owner of the memory.
376  *   @param newLedgerTag - the ledger this memory should be accounted in.
377  *   @param newLedgerOptions - accounting options
378  *   @result An IOReturn code. */
379 
380 	IOReturn setOwnership( task_t newOwner,
381 	    int newLedgerTag,
382 	    IOOptionBits newLedgerOptions );
383 
384 /*! @function getPageCounts
385  *   @abstract Retrieve the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
386  *   @discussion This method returns the number of resident and/or dirty pages encompassed by an IOMemoryDescriptor.
387  *   @param residentPageCount - If non-null, a pointer to a byte count that will return the number of resident pages encompassed by this IOMemoryDescriptor.
388  *   @param dirtyPageCount - If non-null, a pointer to a byte count that will return the number of dirty pages encompassed by this IOMemoryDescriptor.
389  *   @result An IOReturn code. */
390 
391 	IOReturn getPageCounts( IOByteCount * residentPageCount,
392 	    IOByteCount * dirtyPageCount);
393 
394 /*! @function performOperation
395  *   @abstract Perform an operation on the memory descriptor's memory.
396  *   @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.
397  *   @param options The operation to perform on the memory:<br>
398  *   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>
399  *   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.
400  *   @param offset A byte offset into the memory descriptor's memory.
401  *   @param length The length of the data range.
402  *   @result An IOReturn code. */
403 
404 	virtual IOReturn performOperation( IOOptionBits options,
405 	    IOByteCount offset, IOByteCount length );
406 
407 // Used for dedicated communications for IODMACommand
408 	virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
409 
410 /*! @function getPhysicalSegment
411  *   @abstract Break a memory descriptor into its physically contiguous segments.
412  *   @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.
413  *   @param offset A byte offset into the memory whose physical address to return.
414  *   @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
415  *   @result A physical address, or zero if the offset is beyond the length of the memory. */
416 
417 #ifdef __LP64__
418 	virtual addr64_t getPhysicalSegment( IOByteCount   offset,
419 	    IOByteCount * length,
420 	    IOOptionBits  options = 0 ) = 0;
421 #else /* !__LP64__ */
422 	virtual addr64_t getPhysicalSegment( IOByteCount   offset,
423 	    IOByteCount * length,
424 	    IOOptionBits  options );
425 #endif /* !__LP64__ */
426 
427 	virtual uint64_t getPreparationID( void );
428 	void             setPreparationID( void );
429 
430 	void     setVMTags(uint32_t kernelTag, uint32_t userTag);
431 	uint32_t getVMTag(vm_map_t map);
432 
433 #ifdef KERNEL_PRIVATE
434 	uint64_t getDescriptorID( void );
435 	void     setDescriptorID( void );
436 
437 	IOReturn ktraceEmitPhysicalSegments( void );
438 #endif
439 
440 #ifdef XNU_KERNEL_PRIVATE
441 	IOMemoryDescriptorReserved * getKernelReserved( void );
442 	void                         cleanKernelReserved(IOMemoryDescriptorReserved * reserved);
443 	IOReturn dmaMap(
444 		IOMapper                    * mapper,
445 		IOMemoryDescriptor          * memory,
446 		IODMACommand                * command,
447 		const IODMAMapSpecification * mapSpec,
448 		uint64_t                      offset,
449 		uint64_t                      length,
450 		uint64_t                    * mapAddress,
451 		uint64_t                    * mapLength);
452 	IOReturn dmaUnmap(
453 		IOMapper                    * mapper,
454 		IODMACommand                * command,
455 		uint64_t                      offset,
456 		uint64_t                      mapAddress,
457 		uint64_t                      mapLength);
458 	void dmaMapRecord(
459 		IOMapper                    * mapper,
460 		IODMACommand                * command,
461 		uint64_t                      mapLength);
462 #endif
463 
464 private:
465 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 0);
466 #ifdef __LP64__
467 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 1);
468 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 2);
469 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 3);
470 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 4);
471 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 5);
472 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 6);
473 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 7);
474 #else /* !__LP64__ */
475 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 1);
476 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 2);
477 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 3);
478 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 4);
479 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 5);
480 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 6);
481 	OSMetaClassDeclareReservedUsedX86(IOMemoryDescriptor, 7);
482 #endif /* !__LP64__ */
483 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 8);
484 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 9);
485 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 10);
486 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 11);
487 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 12);
488 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 13);
489 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 14);
490 	OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 15);
491 
492 protected:
493 	virtual void free(void) APPLE_KEXT_OVERRIDE;
494 public:
495 	static void initialize( void );
496 
497 public:
498 /*! @function withAddress
499  *   @abstract Create an IOMemoryDescriptor to describe one virtual range of the kernel task.
500  *   @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the kernel map.  This memory descriptor needs to be prepared before it can be used to extract data from the memory described.
501  *   @param address The virtual address of the first byte in the memory.
502  *   @param withLength The length of memory.
503  *   @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.
504  *   @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
505 
506 	static OSPtr<IOMemoryDescriptor>  withAddress(void *       address,
507 	    IOByteCount  withLength,
508 	    IODirection  withDirection);
509 
510 #ifndef __LP64__
511 	static OSPtr<IOMemoryDescriptor>  withAddress(IOVirtualAddress address,
512 	    IOByteCount  withLength,
513 	    IODirection  withDirection,
514 	    task_t       withTask) APPLE_KEXT_DEPRECATED;                                 /* use withAddressRange() and prepare() instead */
515 #endif /* !__LP64__ */
516 
517 /*! @function withPhysicalAddress
518  *   @abstract Create an IOMemoryDescriptor to describe one physical range.
519  *   @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single physical memory range.
520  *   @param address The physical address of the first byte in the memory.
521  *   @param withLength The length of memory.
522  *   @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.
523  *   @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
524 
525 	static OSPtr<IOMemoryDescriptor>  withPhysicalAddress(
526 		IOPhysicalAddress       address,
527 		IOByteCount             withLength,
528 		IODirection             withDirection );
529 
530 #ifndef __LP64__
531 	static OSPtr<IOMemoryDescriptor>  withRanges(IOVirtualRange * ranges,
532 	    UInt32           withCount,
533 	    IODirection      withDirection,
534 	    task_t           withTask,
535 	    bool             asReference = false) APPLE_KEXT_DEPRECATED;                                 /* use withAddressRanges() instead */
536 #endif /* !__LP64__ */
537 
538 /*! @function withAddressRange
539  *   @abstract Create an IOMemoryDescriptor to describe one virtual range of the specified map.
540  *   @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single virtual memory range mapped into the specified map.  This memory descriptor needs to be prepared before it can be used to extract data from the memory described.
541  *   @param address The virtual address of the first byte in the memory.
542  *   @param length The length of memory.
543  *   @param options
544  *       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.
545  *   @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. The task argument may be NULL to specify memory by physical address.
546  *   @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
547 
548 	static OSPtr<IOMemoryDescriptor>  withAddressRange(
549 		mach_vm_address_t address,
550 		mach_vm_size_t    length,
551 		IOOptionBits      options,
552 		task_t            task);
553 
554 /*! @function withAddressRanges
555  *   @abstract Create an IOMemoryDescriptor to describe one or more virtual ranges.
556  *   @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.  This memory descriptor needs to be prepared before it can be used to extract data from the memory described.
557  *   @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.
558  *   @param rangeCount The member count of the ranges array.
559  *   @param options
560  *       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.
561  *       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.
562  *   @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. The task argument may be NULL to specify memory by physical address.
563  *   @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
564 
565 	static OSPtr<IOMemoryDescriptor>  withAddressRanges(
566 		IOAddressRange * ranges,
567 		UInt32           rangeCount,
568 		IOOptionBits     options,
569 		task_t           task);
570 
571 /*! @function withOptions
572  *   @abstract Master initialiser for all variants of memory descriptors.
573  *   @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.
574  *
575  *
576  *   @param buffers A pointer to an array of IOAddressRange when options:type is kIOMemoryTypeVirtual64 or kIOMemoryTypePhysical64 or a 64bit kernel. For type UPL it is a upl_t returned by the mach/memory_object_types.h apis, primarily used internally by the UBC. IOVirtualRanges or IOPhysicalRanges are 32 bit only types for use when options:type is kIOMemoryTypeVirtual or kIOMemoryTypePhysical on 32bit kernels.
577  *
578  *   @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.
579  *
580  *   @param offset Only used when options:type = UPL, in which case this field contains an offset for the memory within the buffers upl.
581  *
582  *   @param task Only used options:type = Virtual, The task each of the virtual ranges are mapped into.
583  *
584  *   @param options
585  *       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.
586  *       kIOMemoryTypeMask (options:type)	kIOMemoryTypeVirtual64, kIOMemoryTypeVirtual, kIOMemoryTypePhysical64, 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.
587  *       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.
588  *       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.
589  *
590  *   @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.
591  *
592  *   @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
593 
594 	static OSPtr<IOMemoryDescriptor> withOptions(void *       buffers,
595 	    UInt32       count,
596 	    UInt32       offset,
597 	    task_t       task,
598 	    IOOptionBits options,
599 	    IOMapper *   mapper = kIOMapperSystem);
600 
601 #ifndef __LP64__
602 	static OSPtr<IOMemoryDescriptor>  withPhysicalRanges(
603 		IOPhysicalRange *   ranges,
604 		UInt32              withCount,
605 		IODirection         withDirection,
606 		bool                asReference = false) APPLE_KEXT_DEPRECATED;                             /* use withOptions() and kIOMemoryTypePhysical instead */
607 #endif /* !__LP64__ */
608 
609 #ifndef __LP64__
610 	static OSPtr<IOMemoryDescriptor>  withSubRange(IOMemoryDescriptor *of,
611 	    IOByteCount offset,
612 	    IOByteCount length,
613 	    IODirection withDirection) APPLE_KEXT_DEPRECATED;                                  /* use IOSubMemoryDescriptor::withSubRange() and kIOMemoryThreadSafe instead */
614 #endif /* !__LP64__ */
615 
616 /*! @function withPersistentMemoryDescriptor
617  *   @abstract Copy constructor that generates a new memory descriptor if the backing memory for the same task's virtual address and length has changed.
618  *   @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.
619  *   @param originalMD The memory descriptor to be duplicated.
620  *   @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. */
621 	static OSPtr<IOMemoryDescriptor>
622 	withPersistentMemoryDescriptor(IOMemoryDescriptor *originalMD);
623 
624 #ifndef __LP64__
625 // obsolete initializers
626 // - initWithOptions is the designated initializer
627 	virtual bool initWithAddress(void *       address,
628 	    IOByteCount  withLength,
629 	    IODirection  withDirection) APPLE_KEXT_DEPRECATED;                      /* use initWithOptions() instead */
630 	virtual bool initWithAddress(IOVirtualAddress address,
631 	    IOByteCount  withLength,
632 	    IODirection  withDirection,
633 	    task_t       withTask) APPLE_KEXT_DEPRECATED;                      /* use initWithOptions() instead */
634 	virtual bool initWithPhysicalAddress(
635 		IOPhysicalAddress      address,
636 		IOByteCount            withLength,
637 		IODirection            withDirection ) APPLE_KEXT_DEPRECATED;                  /* use initWithOptions() instead */
638 	virtual bool initWithRanges(IOVirtualRange * ranges,
639 	    UInt32           withCount,
640 	    IODirection      withDirection,
641 	    task_t           withTask,
642 	    bool             asReference = false) APPLE_KEXT_DEPRECATED;                     /* use initWithOptions() instead */
643 	virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
644 	    UInt32           withCount,
645 	    IODirection      withDirection,
646 	    bool             asReference = false) APPLE_KEXT_DEPRECATED;                             /* use initWithOptions() instead */
647 #endif /* __LP64__ */
648 
649 /*! @function getDirection
650  *   @abstract Accessor to get the direction the memory descriptor was created with.
651  *   @discussion This method returns the direction the memory descriptor was created with.
652  *   @result The direction. */
653 
654 	virtual IODirection getDirection() const;
655 
656 /*! @function getLength
657  *   @abstract Accessor to get the length of the memory descriptor (over all its ranges).
658  *   @discussion This method returns the total length of the memory described by the descriptor, ie. the sum of its ranges' lengths.
659  *   @result The byte count. */
660 
661 	virtual IOByteCount getLength() const;
662 
663 #define IOMEMORYDESCRIPTOR_SUPPORTS_GETDMAMAPLENGTH
664 	uint64_t getDMAMapLength(uint64_t * offset = NULL);
665 
666 /*! @function setTag
667  *   @abstract Set the tag for the memory descriptor.
668  *   @discussion This method sets the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
669  *   @param tag The tag. */
670 
671 	virtual void setTag( IOOptionBits tag );
672 
673 /*! @function getTag
674  *   @abstract Accessor to the retrieve the tag for the memory descriptor.
675  *   @discussion This method returns the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
676  *   @result The tag. */
677 
678 	virtual IOOptionBits getTag( void );
679 
680 /*! @function getFlags
681  *   @abstract Accessor to the retrieve the options the memory descriptor was created with.
682  *   @discussion Accessor to the retrieve the options the memory descriptor was created with, and flags with its state. These bits are defined by the kIOMemory* enum.
683  *   @result The flags bitfield. */
684 
685 	uint64_t getFlags(void);
686 
687 /*! @function readBytes
688  *   @abstract Copy data from the memory descriptor's buffer to the specified buffer.
689  *   @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.
690  *   @param offset A byte offset into the memory descriptor's memory.
691  *   @param bytes The caller supplied buffer to copy the data to.
692  *   @param withLength The length of the data to copy.
693  *   @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. Development/debug kernel builds will assert if the offset is beyond the length of the descriptor. */
694 
695 	virtual IOByteCount readBytes(IOByteCount offset,
696 	    void * bytes, IOByteCount withLength);
697 
698 /*! @function writeBytes
699  *   @abstract Copy data to the memory descriptor's buffer from the specified buffer.
700  *   @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.
701  *   @param offset A byte offset into the memory descriptor's memory.
702  *   @param bytes The caller supplied buffer to copy the data from.
703  *   @param withLength The length of the data to copy.
704  *   @result The number of bytes copied, zero will be returned if the specified offset is beyond the length of the descriptor. Development/debug kernel builds will assert if the offset is beyond the length of the descriptor. */
705 
706 	virtual IOByteCount writeBytes(IOByteCount offset,
707 	    const void * bytes, IOByteCount withLength);
708 
709 #ifndef __LP64__
710 	virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
711 	    IOByteCount * length);
712 #endif /* !__LP64__ */
713 
714 /*! @function getPhysicalAddress
715  *   @abstract Return the physical address of the first byte in the memory.
716  *   @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.
717  *   @result A physical address. */
718 
719 	IOPhysicalAddress getPhysicalAddress();
720 
721 #ifndef __LP64__
722 	virtual void * getVirtualSegment(IOByteCount offset,
723 	    IOByteCount * length) APPLE_KEXT_DEPRECATED;                             /* use map() and getVirtualAddress() instead */
724 #endif /* !__LP64__ */
725 
726 /*! @function prepare
727  *   @abstract Prepare the memory for an I/O transfer.
728  *   @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.
729  *   @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
730  *   @result An IOReturn code. */
731 
732 	virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) = 0;
733 
734 /*! @function complete
735  *   @abstract Complete processing of the memory after an I/O transfer finishes.
736  *   @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.
737  *   @param forDirection DEPRECATED The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
738  *   @result An IOReturn code. */
739 
740 	virtual IOReturn complete(IODirection forDirection = kIODirectionNone) = 0;
741 
742 /*
743  * Mapping functions.
744  */
745 
746 /*! @function createMappingInTask
747  *   @abstract Maps a IOMemoryDescriptor into a task.
748  *   @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.
749  *   @param intoTask Sets the target task for the mapping. Pass kernel_task for the kernel address space.
750  *   @param atAddress If a placed mapping is requested, atAddress specifies its address, and the kIOMapAnywhere should not be set. Otherwise, atAddress is ignored.
751  *   @param options Mapping options are defined in IOTypes.h,<br>
752  *       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>
753  *       kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
754  *       kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
755  *       kIOMapReadOnly to allow only read only accesses to the memory - writes will cause and access fault.<br>
756  *       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>
757  *       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>
758  *       kIOMapPrefault will try to prefault the pages corresponding to the mapping. This must not be done on the kernel task, and the memory must have been wired via prepare(). Otherwise, the function will fail.<br>
759  *   @param offset Is a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default to map all the memory.
760  *   @param length Is the length of the mapping requested for a subset of the IOMemoryDescriptor. Zero is the default to map all the memory.
761  *   @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. */
762 
763 	OSPtr<IOMemoryMap>        createMappingInTask(
764 		task_t                  intoTask,
765 		mach_vm_address_t       atAddress,
766 		IOOptionBits            options,
767 		mach_vm_size_t          offset = 0,
768 		mach_vm_size_t          length = 0 );
769 
770 #ifndef __LP64__
771 	virtual OSPtr<IOMemoryMap>       map(
772 		task_t          intoTask,
773 		IOVirtualAddress        atAddress,
774 		IOOptionBits            options,
775 		IOByteCount             offset = 0,
776 		IOByteCount             length = 0 ) APPLE_KEXT_DEPRECATED;/* use createMappingInTask() instead */
777 #endif /* !__LP64__ */
778 
779 /*! @function map
780  *   @abstract Maps a IOMemoryDescriptor into the kernel map.
781  *   @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.
782  *   @param options Mapping options as in the full version of the createMappingInTask method, with kIOMapAnywhere assumed.
783  *   @result See the full version of the createMappingInTask method. */
784 
785 	virtual OSPtr<IOMemoryMap>       map(
786 		IOOptionBits            options = 0 );
787 
788 /*! @function setMapping
789  *   @abstract Establishes an already existing mapping.
790  *   @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.
791  *   @param task Address space in which the mapping exists.
792  *   @param mapAddress Virtual address of the mapping.
793  *   @param options Caching and read-only attributes of the mapping.
794  *   @result A IOMemoryMap object created to represent the mapping. */
795 
796 	virtual OSPtr<IOMemoryMap>       setMapping(
797 		task_t          task,
798 		IOVirtualAddress        mapAddress,
799 		IOOptionBits            options = 0 );
800 
801 /*! @function setMapperOptions
802  *   @abstract Set the IOMapper options
803  *   @discussion This method sets the IOMapper options
804  *   @param options  IOMapper options to be set. */
805 
806 	void setMapperOptions( uint16_t options );
807 
808 /*! @function getMapperOptions
809  *   @abstract return IOMapper Options
810  *   @discussion This method returns IOMapper Options set earlier using setMapperOptions
811  *   @result IOMapper options set. */
812 
813 	uint16_t getMapperOptions( void );
814 
815 // Following methods are private implementation
816 
817 #ifdef __LP64__
818 	virtual
819 #endif /* __LP64__ */
820 	IOReturn redirect( task_t safeTask, bool redirect );
821 
822 	IOReturn handleFault(
823 		void *                  _pager,
824 		mach_vm_size_t          sourceOffset,
825 		mach_vm_size_t          length);
826 
827 	IOReturn populateDevicePager(
828 		void *                  pager,
829 		vm_map_t                addressMap,
830 		mach_vm_address_t       address,
831 		mach_vm_size_t          sourceOffset,
832 		mach_vm_size_t          length,
833 		IOOptionBits            options );
834 
835 	virtual LIBKERN_RETURNS_NOT_RETAINED IOMemoryMap *      makeMapping(
836 		IOMemoryDescriptor *    owner,
837 		task_t                  intoTask,
838 		IOVirtualAddress        atAddress,
839 		IOOptionBits            options,
840 		IOByteCount             offset,
841 		IOByteCount             length );
842 
843 #if KERNEL_PRIVATE
844 /*! @function copyContext
845  *   @abstract Accessor to the retrieve the context previously set for the memory descriptor.
846  *   @discussion This method returns the context for the memory descriptor. The context is not interpreted by IOMemoryDescriptor.
847  *   @result The context, returned with an additional retain to be released by the caller. */
848 	OSObject * copyContext(void) const;
849 
850 /*! @function setContext
851  *   @abstract Set a context object for the memory descriptor. The context is not interpreted by IOMemoryDescriptor.
852  *   @discussion The context is retained, and will be released when the memory descriptor is freed or when a new context object is set.
853  */
854 	void setContext(OSObject * context);
855 #endif
856 
857 protected:
858 	virtual void                addMapping(
859 		IOMemoryMap *           mapping );
860 
861 	virtual void                removeMapping(
862 		IOMemoryMap *           mapping );
863 
864 	virtual IOReturn doMap(
865 		vm_map_t                addressMap,
866 		IOVirtualAddress *      atAddress,
867 		IOOptionBits            options,
868 		IOByteCount             sourceOffset = 0,
869 		IOByteCount             length = 0 );
870 
871 	virtual IOReturn doUnmap(
872 		vm_map_t                addressMap,
873 		IOVirtualAddress        logical,
874 		IOByteCount             length );
875 };
876 
877 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
878 
879 /*! @class IOMemoryMap : public OSObject
880  *   @abstract A class defining common methods for describing a memory mapping.
881  *   @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. */
882 
883 class IOMemoryMap : public OSObject
884 {
885 	OSDeclareDefaultStructorsWithDispatch(IOMemoryMap);
886 #ifdef XNU_KERNEL_PRIVATE
887 public:
888 	IOOptionBits         fOptions;
889 	OSPtr<IOMemoryDescriptor>  fMemory;
890 	OSPtr<IOMemoryMap>         fSuperMap;
891 	mach_vm_size_t       fOffset;
892 	mach_vm_address_t    fAddress;
893 	mach_vm_size_t       fLength;
894 	task_t               fAddressTask;
895 	vm_map_t             fAddressMap;
896 	upl_t                fRedirUPL;
897 	uint8_t              fUserClientUnmap;
898 #if IOTRACKING
899 	IOTrackingUser       fTracking;
900 #endif
901 #endif /* XNU_KERNEL_PRIVATE */
902 
903 protected:
904 	virtual void taggedRelease(const void *tag = NULL) const APPLE_KEXT_OVERRIDE;
905 	virtual void free(void) APPLE_KEXT_OVERRIDE;
906 
907 public:
908 /*! @function getVirtualAddress
909  *   @abstract Accessor to the virtual address of the first byte in the mapping.
910  *   @discussion This method returns the virtual address of the first byte in the mapping. Since the IOVirtualAddress is only 32bit in 32bit kernels, the getAddress() method should be used for compatibility with 64bit task mappings.
911  *   @result A virtual address. */
912 
913 	virtual IOVirtualAddress    getVirtualAddress(void);
914 
915 /*! @function getPhysicalSegment
916  *   @abstract Break a mapping into its physically contiguous segments.
917  *   @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.
918  *   @param offset A byte offset into the mapping whose physical address to return.
919  *   @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
920  *   @result A physical address, or zero if the offset is beyond the length of the mapping. */
921 
922 #ifdef __LP64__
923 	virtual IOPhysicalAddress   getPhysicalSegment(IOByteCount offset,
924 	    IOByteCount * length,
925 	    IOOptionBits  options = 0);
926 #else /* !__LP64__ */
927 	virtual IOPhysicalAddress   getPhysicalSegment(IOByteCount offset,
928 	    IOByteCount * length);
929 #endif /* !__LP64__ */
930 
931 /*! @function getPhysicalAddress
932  *   @abstract Return the physical address of the first byte in the mapping.
933  *   @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.
934  *   @result A physical address. */
935 
936 	IOPhysicalAddress getPhysicalAddress(void);
937 
938 /*! @function getLength
939  *   @abstract Accessor to the length of the mapping.
940  *   @discussion This method returns the length of the mapping.
941  *   @result A byte count. */
942 
943 	virtual IOByteCount         getLength(void);
944 
945 /*! @function getAddressTask
946  *   @abstract Accessor to the task of the mapping.
947  *   @discussion This method returns the mach task the mapping exists in.
948  *   @result A mach task_t. */
949 
950 	virtual task_t              getAddressTask();
951 
952 /*! @function getMemoryDescriptor
953  *   @abstract Accessor to the IOMemoryDescriptor the mapping was created from.
954  *   @discussion This method returns the IOMemoryDescriptor the mapping was created from.
955  *   @result An IOMemoryDescriptor reference, which is valid while the IOMemoryMap object is retained. It should not be released by the caller. */
956 
957 	virtual IOMemoryDescriptor * getMemoryDescriptor();
958 
959 /*! @function getMapOptions
960  *   @abstract Accessor to the options the mapping was created with.
961  *   @discussion This method returns the options to IOMemoryDescriptor::map the mapping was created with.
962  *   @result Options for the mapping, including cache settings. */
963 
964 	virtual IOOptionBits        getMapOptions();
965 
966 /*! @function unmap
967  *   @abstract Force the IOMemoryMap to unmap, without destroying the object.
968  *   @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.
969  *   @result An IOReturn code. */
970 
971 	virtual IOReturn            unmap();
972 
973 	virtual void                taskDied();
974 
975 /*! @function redirect
976  *   @abstract Replace the memory mapped in a process with new backing memory.
977  *   @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.
978  *   @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.
979  *   @param options Mapping options are defined in IOTypes.h, and are documented in IOMemoryDescriptor::map()
980  *   @param offset As with IOMemoryDescriptor::map(), a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default.
981  *   @result An IOReturn code. */
982 
983 #ifndef __LP64__
984 // For 32 bit XNU, there is a 32 bit (IOByteCount) and a 64 bit (mach_vm_size_t) interface;
985 // for 64 bit, these fall together on the 64 bit one.
986 	virtual IOReturn            redirect(IOMemoryDescriptor * newBackingMemory,
987 	    IOOptionBits         options,
988 	    IOByteCount          offset = 0);
989 #endif
990 	virtual IOReturn            redirect(IOMemoryDescriptor * newBackingMemory,
991 	    IOOptionBits         options,
992 	    mach_vm_size_t       offset = 0);
993 
994 #ifdef __LP64__
995 /*! @function getAddress
996  *   @abstract Accessor to the virtual address of the first byte in the mapping.
997  *   @discussion This method returns the virtual address of the first byte in the mapping.
998  *   @result A virtual address. */
999 	inline mach_vm_address_t    getAddress() __attribute__((always_inline));
1000 /*! @function getSize
1001  *   @abstract Accessor to the length of the mapping.
1002  *   @discussion This method returns the length of the mapping.
1003  *   @result A byte count. */
1004 	inline mach_vm_size_t       getSize() __attribute__((always_inline));
1005 #else /* !__LP64__ */
1006 /*! @function getAddress
1007  *   @abstract Accessor to the virtual address of the first byte in the mapping.
1008  *   @discussion This method returns the virtual address of the first byte in the mapping.
1009  *   @result A virtual address. */
1010 	virtual mach_vm_address_t   getAddress();
1011 /*! @function getSize
1012  *   @abstract Accessor to the length of the mapping.
1013  *   @discussion This method returns the length of the mapping.
1014  *   @result A byte count. */
1015 	virtual mach_vm_size_t      getSize();
1016 #endif /* !__LP64__ */
1017 
1018 #ifdef XNU_KERNEL_PRIVATE
1019 // for IOMemoryDescriptor use
1020 	IOMemoryMap *  copyCompatible( IOMemoryMap * newMapping );
1021 
1022 	bool init(
1023 		task_t                  intoTask,
1024 		mach_vm_address_t       toAddress,
1025 		IOOptionBits            options,
1026 		mach_vm_size_t          offset,
1027 		mach_vm_size_t          length );
1028 
1029 	bool    setMemoryDescriptor(IOMemoryDescriptor * _memory, mach_vm_size_t _offset);
1030 
1031 	IOReturn redirect(
1032 		task_t                  intoTask, bool redirect );
1033 
1034 	IOReturn userClientUnmap();
1035 #endif /* XNU_KERNEL_PRIVATE */
1036 
1037 	IOReturn wireRange(
1038 		uint32_t                options,
1039 		mach_vm_size_t          offset,
1040 		mach_vm_size_t          length);
1041 
1042 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 0);
1043 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 1);
1044 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 2);
1045 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 3);
1046 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 4);
1047 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 5);
1048 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 6);
1049 	OSMetaClassDeclareReservedUnused(IOMemoryMap, 7);
1050 };
1051 
1052 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1053 #ifdef XNU_KERNEL_PRIVATE
1054 // Also these flags should not overlap with the options to
1055 //	IOMemoryDescriptor::initWithRanges(... IOOptionsBits options);
1056 enum {
1057 	_kIOMemorySourceSegment     = 0x00002000
1058 };
1059 #endif /* XNU_KERNEL_PRIVATE */
1060 
1061 // The following classes are private implementation of IOMemoryDescriptor - they
1062 // should not be referenced directly, just through the public API's in the
1063 // IOMemoryDescriptor class. For example, an IOGeneralMemoryDescriptor instance
1064 // might be created by IOMemoryDescriptor::withAddressRange(), but there should be
1065 // no need to reference as anything but a generic IOMemoryDescriptor *.
1066 
1067 class IOGeneralMemoryDescriptor : public IOMemoryDescriptor
1068 {
1069 	OSDeclareDefaultStructors(IOGeneralMemoryDescriptor);
1070 
1071 public:
1072 	union Ranges {
1073 		IOVirtualRange   *v;
1074 		IOAddressRange   *v64;
1075 		IOPhysicalRange  *p;
1076 		void             *uio;
1077 	};
1078 protected:
1079 	Ranges              _ranges;
1080 	unsigned            _rangesCount;   /* number of address ranges in list */
1081 #ifndef __LP64__
1082 	bool                _rangesIsAllocated;/* is list allocated by us? */
1083 #endif /* !__LP64__ */
1084 
1085 	task_t              _task;           /* task where all ranges are mapped to */
1086 
1087 	union {
1088 		IOVirtualRange  v;
1089 		IOPhysicalRange p;
1090 	}                   _singleRange;  /* storage space for a single range */
1091 
1092 	unsigned            _wireCount;    /* number of outstanding wires */
1093 
1094 #ifndef __LP64__
1095 	uintptr_t _cachedVirtualAddress;
1096 
1097 	IOPhysicalAddress   _cachedPhysicalAddress;
1098 #endif /* !__LP64__ */
1099 
1100 	bool                _initialized;  /* has superclass been initialized? */
1101 
1102 public:
1103 	virtual void free() APPLE_KEXT_OVERRIDE;
1104 
1105 	virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const APPLE_KEXT_OVERRIDE;
1106 
1107 	virtual uint64_t getPreparationID( void ) APPLE_KEXT_OVERRIDE;
1108 
1109 #ifdef XNU_KERNEL_PRIVATE
1110 // Internal APIs may be made virtual at some time in the future.
1111 	IOReturn wireVirtual(IODirection forDirection);
1112 	IOReturn dmaMap(
1113 		IOMapper                    * mapper,
1114 		IOMemoryDescriptor          * memory,
1115 		IODMACommand                * command,
1116 		const IODMAMapSpecification * mapSpec,
1117 		uint64_t                      offset,
1118 		uint64_t                      length,
1119 		uint64_t                    * mapAddress,
1120 		uint64_t                    * mapLength);
1121 	bool initMemoryEntries(size_t size, IOMapper * mapper);
1122 
1123 	IOMemoryReference * memoryReferenceAlloc(uint32_t capacity,
1124 	    IOMemoryReference * realloc);
1125 	void memoryReferenceFree(IOMemoryReference * ref);
1126 	void memoryReferenceRelease(IOMemoryReference * ref);
1127 
1128 	IOReturn memoryReferenceCreate(
1129 		IOOptionBits         options,
1130 		IOMemoryReference ** reference);
1131 
1132 	IOReturn memoryReferenceMap(IOMemoryReference * ref,
1133 	    vm_map_t            map,
1134 	    mach_vm_size_t      inoffset,
1135 	    mach_vm_size_t      size,
1136 	    IOOptionBits        options,
1137 	    mach_vm_address_t * inaddr);
1138 
1139 	IOReturn memoryReferenceMapNew(IOMemoryReference * ref,
1140 	    vm_map_t            map,
1141 	    mach_vm_size_t      inoffset,
1142 	    mach_vm_size_t      size,
1143 	    IOOptionBits        options,
1144 	    mach_vm_address_t * inaddr);
1145 
1146 	static IOReturn memoryReferenceSetPurgeable(
1147 		IOMemoryReference * ref,
1148 		IOOptionBits newState,
1149 		IOOptionBits * oldState);
1150 	static IOReturn memoryReferenceSetOwnership(
1151 		IOMemoryReference * ref,
1152 		task_t newOwner,
1153 		int newLedgerTag,
1154 		IOOptionBits newLedgerOptions);
1155 	static IOReturn memoryReferenceGetPageCounts(
1156 		IOMemoryReference * ref,
1157 		IOByteCount       * residentPageCount,
1158 		IOByteCount       * dirtyPageCount);
1159 
1160 	static uint64_t memoryReferenceGetDMAMapLength(
1161 		IOMemoryReference * ref,
1162 		uint64_t * offset);
1163 
1164 	IOByteCount readBytes(IOByteCount offset,
1165 	    void * bytes, IOByteCount withLength) override;
1166 	IOByteCount writeBytes(IOByteCount offset,
1167 	    const void * bytes, IOByteCount withLength) override;
1168 
1169 #endif
1170 
1171 private:
1172 
1173 #ifndef __LP64__
1174 	virtual void setPosition(IOByteCount position);
1175 	virtual void mapIntoKernel(unsigned rangeIndex);
1176 	virtual void unmapFromKernel();
1177 #endif /* !__LP64__ */
1178 
1179 // Internal
1180 	OSPtr<_IOMemoryDescriptorMixedData> _memoryEntries;
1181 	unsigned int    _pages;
1182 	ppnum_t         _highestPage;
1183 	uint32_t        __iomd_reservedA;
1184 	uint32_t        __iomd_reservedB;
1185 
1186 	IOLock *        _prepareLock;
1187 
1188 public:
1189 /*
1190  * IOMemoryDescriptor required methods
1191  */
1192 
1193 // Master initaliser
1194 	virtual bool initWithOptions(void *         buffers,
1195 	    UInt32         count,
1196 	    UInt32         offset,
1197 	    task_t         task,
1198 	    IOOptionBits   options,
1199 	    IOMapper *     mapper = kIOMapperSystem) APPLE_KEXT_OVERRIDE;
1200 
1201 #ifndef __LP64__
1202 // Secondary initialisers
1203 	virtual bool initWithAddress(void *         address,
1204 	    IOByteCount    withLength,
1205 	    IODirection    withDirection) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1206 
1207 	virtual bool initWithAddress(IOVirtualAddress address,
1208 	    IOByteCount    withLength,
1209 	    IODirection    withDirection,
1210 	    task_t         withTask) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1211 
1212 	virtual bool initWithPhysicalAddress(
1213 		IOPhysicalAddress      address,
1214 		IOByteCount            withLength,
1215 		IODirection            withDirection ) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1216 
1217 	virtual bool initWithRanges(        IOVirtualRange * ranges,
1218 	    UInt32           withCount,
1219 	    IODirection      withDirection,
1220 	    task_t           withTask,
1221 	    bool             asReference = false) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1222 
1223 	virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
1224 	    UInt32           withCount,
1225 	    IODirection      withDirection,
1226 	    bool             asReference = false) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1227 
1228 	virtual addr64_t getPhysicalSegment64( IOByteCount offset,
1229 	    IOByteCount * length ) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1230 
1231 	virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
1232 	    IOByteCount * length) APPLE_KEXT_OVERRIDE;
1233 
1234 	virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
1235 	    IOByteCount * length) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1236 
1237 	virtual void * getVirtualSegment(IOByteCount offset,
1238 	    IOByteCount * length) APPLE_KEXT_OVERRIDE APPLE_KEXT_DEPRECATED;
1239 #endif /* !__LP64__ */
1240 
1241 	virtual IOReturn setPurgeable( IOOptionBits newState,
1242 	    IOOptionBits * oldState ) APPLE_KEXT_OVERRIDE;
1243 
1244 	IOReturn setOwnership( task_t newOwner,
1245 	    int newLedgerTag,
1246 	    IOOptionBits newLedgerOptions );
1247 
1248 	virtual addr64_t getPhysicalSegment( IOByteCount   offset,
1249 	    IOByteCount * length,
1250 #ifdef __LP64__
1251 	    IOOptionBits  options = 0 ) APPLE_KEXT_OVERRIDE;
1252 #else /* !__LP64__ */
1253 	    IOOptionBits  options)APPLE_KEXT_OVERRIDE;
1254 #endif /* !__LP64__ */
1255 
1256 	virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
1257 
1258 	virtual IOReturn complete(IODirection forDirection = kIODirectionNone) APPLE_KEXT_OVERRIDE;
1259 
1260 	virtual LIBKERN_RETURNS_NOT_RETAINED IOMemoryMap *      makeMapping(
1261 		IOMemoryDescriptor *    owner,
1262 		task_t                  intoTask,
1263 		IOVirtualAddress        atAddress,
1264 		IOOptionBits            options,
1265 		IOByteCount             offset,
1266 		IOByteCount             length ) APPLE_KEXT_OVERRIDE;
1267 
1268 	virtual IOReturn doMap(
1269 		vm_map_t                addressMap,
1270 		IOVirtualAddress *      atAddress,
1271 		IOOptionBits            options,
1272 		IOByteCount             sourceOffset = 0,
1273 		IOByteCount             length = 0 ) APPLE_KEXT_OVERRIDE;
1274 
1275 	virtual IOReturn doUnmap(
1276 		vm_map_t                addressMap,
1277 		IOVirtualAddress        logical,
1278 		IOByteCount             length ) APPLE_KEXT_OVERRIDE;
1279 
1280 	virtual bool serialize(OSSerialize *s) const APPLE_KEXT_OVERRIDE;
1281 
1282 // Factory method for cloning a persistent IOMD, see IOMemoryDescriptor
1283 	static OSPtr<IOMemoryDescriptor>
1284 	withPersistentMemoryDescriptor(IOGeneralMemoryDescriptor *originalMD);
1285 
1286 	IOOptionBits memoryReferenceCreateOptions(IOOptionBits options, IOMemoryMap * map);
1287 };
1288 
1289 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1290 
1291 #ifdef __LP64__
1292 mach_vm_address_t
getAddress()1293 IOMemoryMap::getAddress()
1294 {
1295 	return getVirtualAddress();
1296 }
1297 
1298 mach_vm_size_t
getSize()1299 IOMemoryMap::getSize()
1300 {
1301 	return getLength();
1302 }
1303 #else /* !__LP64__ */
1304 #include <IOKit/IOSubMemoryDescriptor.h>
1305 #endif /* !__LP64__ */
1306 
1307 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
1308 
1309 extern bool iokit_iomd_setownership_enabled;
1310 
1311 #endif /* !_IOMEMORYDESCRIPTOR_H */
1312