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1 /*
2 * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
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27 */
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 #include <mach/memory_object_types.h>
38
39 class IOMemoryMap;
40 class IOMapper;
41
42 /*
43 * Direction of transfer, with respect to the described memory.
44 */
45 #ifdef __LP64__
46 enum
47 #else /* !__LP64__ */
48 enum IODirection
49 #endif /* !__LP64__ */
50 {
51 kIODirectionNone = 0x0, // same as VM_PROT_NONE
52 kIODirectionIn = 0x1, // User land 'read', same as VM_PROT_READ
53 kIODirectionOut = 0x2, // User land 'write', same as VM_PROT_WRITE
54 kIODirectionOutIn = kIODirectionOut | kIODirectionIn,
55 kIODirectionInOut = kIODirectionIn | kIODirectionOut
56 };
57 #ifdef __LP64__
58 typedef IOOptionBits IODirection;
59 #endif /* __LP64__ */
60
61 /*
62 * IOOptionBits used in the withOptions variant
63 */
64 enum {
65 kIOMemoryDirectionMask = 0x00000007,
66 #ifdef XNU_KERNEL_PRIVATE
67 kIOMemoryAutoPrepare = 0x00000008, // Shared with Buffer MD
68 #endif
69
70 kIOMemoryTypeVirtual = 0x00000010,
71 kIOMemoryTypePhysical = 0x00000020,
72 kIOMemoryTypeUPL = 0x00000030,
73 kIOMemoryTypePersistentMD = 0x00000040, // Persistent Memory Descriptor
74 kIOMemoryTypeUIO = 0x00000050,
75 #ifdef __LP64__
76 kIOMemoryTypeVirtual64 = kIOMemoryTypeVirtual,
77 kIOMemoryTypePhysical64 = kIOMemoryTypePhysical,
78 #else /* !__LP64__ */
79 kIOMemoryTypeVirtual64 = 0x00000060,
80 kIOMemoryTypePhysical64 = 0x00000070,
81 #endif /* !__LP64__ */
82 kIOMemoryTypeMask = 0x000000f0,
83
84 kIOMemoryAsReference = 0x00000100,
85 kIOMemoryBufferPageable = 0x00000400,
86 kIOMemoryMapperNone = 0x00000800,
87 #ifdef XNU_KERNEL_PRIVATE
88 kIOMemoryRedirected = 0x00004000,
89 kIOMemoryPreparedReadOnly = 0x00008000,
90 #endif
91 kIOMemoryPersistent = 0x00010000,
92 #ifdef XNU_KERNEL_PRIVATE
93 kIOMemoryReserved6156215 = 0x00020000,
94 #endif
95 kIOMemoryThreadSafe = 0x00100000, // Shared with Buffer MD
96 };
97
98 #define kIOMapperSystem ((IOMapper *) 0)
99
100 enum
101 {
102 kIOMemoryPurgeableKeepCurrent = 1,
103 kIOMemoryPurgeableNonVolatile = 2,
104 kIOMemoryPurgeableVolatile = 3,
105 kIOMemoryPurgeableEmpty = 4
106 };
107 enum
108 {
109 kIOMemoryIncoherentIOFlush = 1,
110 kIOMemoryIncoherentIOStore = 2,
111 };
112
113 #define IOMEMORYDESCRIPTOR_SUPPORTS_DMACOMMAND 1
114
115 enum
116 {
117 kIOPreparationIDUnprepared = 0,
118 kIOPreparationIDUnsupported = 1,
119 kIOPreparationIDAlwaysPrepared = 2,
120 };
121
122 /*! @class IOMemoryDescriptor : public OSObject
123 @abstract An abstract base class defining common methods for describing physical or virtual memory.
124 @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. */
125
126 class IOMemoryDescriptor : public OSObject
127 {
128 friend class IOMemoryMap;
129
130 OSDeclareDefaultStructors(IOMemoryDescriptor);
131
132 protected:
133 /*! @struct ExpansionData
134 @discussion This structure will be used to expand the capablilties of this class in the future.
135 */
136 struct ExpansionData {
137 void * devicePager;
138 unsigned int pagerContig:1;
139 unsigned int unused:31;
140 IOMemoryDescriptor * memory;
141 };
142
143 /*! @var reserved
144 Reserved for future use. (Internal use only) */
145 ExpansionData * reserved;
146
147 protected:
148 OSSet * _mappings;
149 IOOptionBits _flags;
150 void * _memEntry;
151
152 #ifdef __LP64__
153 uint64_t __iomd_reserved1;
154 uint64_t __iomd_reserved2;
155 uint64_t __iomd_reserved3;
156 uint64_t __iomd_reserved4;
157 #else /* !__LP64__ */
158 IODirection _direction; /* use _flags instead */
159 #endif /* !__LP64__ */
160 IOByteCount _length; /* length of all ranges */
161 IOOptionBits _tag;
162
163 public:
164 typedef IOOptionBits DMACommandOps;
165 #ifndef __LP64__
166 virtual IOPhysicalAddress getSourceSegment( IOByteCount offset,
167 IOByteCount * length ) APPLE_KEXT_DEPRECATED;
168 #endif /* !__LP64__ */
169
170 /*! @function initWithOptions
171 @abstract Master initialiser for all variants of memory descriptors. For a more complete description see IOMemoryDescriptor::withOptions.
172 @discussion Note this function can be used to re-init a previously created memory descriptor.
173 @result true on success, false on failure. */
174 virtual bool initWithOptions(void * buffers,
175 UInt32 count,
176 UInt32 offset,
177 task_t task,
178 IOOptionBits options,
179 IOMapper * mapper = kIOMapperSystem);
180
181 #ifndef __LP64__
182 virtual addr64_t getPhysicalSegment64( IOByteCount offset,
183 IOByteCount * length ) APPLE_KEXT_DEPRECATED; /* use getPhysicalSegment() and kIOMemoryMapperNone instead */
184 #endif /* !__LP64__ */
185
186 /*! @function setPurgeable
187 @abstract Control the purgeable status of a memory descriptors memory.
188 @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.
189 @param newState - the desired new purgeable state of the memory:<br>
190 kIOMemoryPurgeableKeepCurrent - make no changes to the memory's purgeable state.<br>
191 kIOMemoryPurgeableVolatile - make the memory volatile - the memory may be reclaimed by the VM system without saving its contents to backing store.<br>
192 kIOMemoryPurgeableNonVolatile - make the memory nonvolatile - the memory is treated as with usual allocations and must be saved to backing store if paged.<br>
193 kIOMemoryPurgeableEmpty - make the memory volatile, and discard any pages allocated to it.
194 @param oldState - if non-NULL, the previous purgeable state of the memory is returned here:<br>
195 kIOMemoryPurgeableNonVolatile - the memory was nonvolatile.<br>
196 kIOMemoryPurgeableVolatile - the memory was volatile but its content has not been discarded by the VM system.<br>
197 kIOMemoryPurgeableEmpty - the memory was volatile and has been discarded by the VM system.<br>
198 @result An IOReturn code. */
199
200 virtual IOReturn setPurgeable( IOOptionBits newState,
201 IOOptionBits * oldState );
202
203 /*! @function performOperation
204 @abstract Perform an operation on the memory descriptor's memory.
205 @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.
206 @param options The operation to perform on the memory:<br>
207 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>
208 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.
209 @param offset A byte offset into the memory descriptor's memory.
210 @param length The length of the data range.
211 @result An IOReturn code. */
212
213 virtual IOReturn performOperation( IOOptionBits options,
214 IOByteCount offset, IOByteCount length );
215
216 // Used for dedicated communications for IODMACommand
217 virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
218
219 /*! @function getPhysicalSegment
220 @abstract Break a memory descriptor into its physically contiguous segments.
221 @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.
222 @param offset A byte offset into the memory whose physical address to return.
223 @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
224 @result A physical address, or zero if the offset is beyond the length of the memory. */
225
226 #ifdef __LP64__
227 virtual addr64_t getPhysicalSegment( IOByteCount offset,
228 IOByteCount * length,
229 IOOptionBits options = 0 ) = 0;
230 #else /* !__LP64__ */
231 virtual addr64_t getPhysicalSegment( IOByteCount offset,
232 IOByteCount * length,
233 IOOptionBits options );
234 #endif /* !__LP64__ */
235
236 virtual uint64_t getPreparationID( void );
237
238 private:
239 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 0);
240 #ifdef __LP64__
241 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 1);
242 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 2);
243 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 3);
244 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 4);
245 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 5);
246 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 6);
247 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 7);
248 #else /* !__LP64__ */
249 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 1);
250 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 2);
251 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 3);
252 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 4);
253 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 5);
254 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 6);
255 OSMetaClassDeclareReservedUsed(IOMemoryDescriptor, 7);
256 #endif /* !__LP64__ */
257 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 8);
258 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 9);
259 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 10);
260 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 11);
261 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 12);
262 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 13);
263 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 14);
264 OSMetaClassDeclareReservedUnused(IOMemoryDescriptor, 15);
265
266 protected:
267 virtual void free();
268 public:
269 static void initialize( void );
270
271 public:
272 /*! @function withAddress
273 @abstract Create an IOMemoryDescriptor to describe one virtual range of the kernel task.
274 @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.
275 @param address The virtual address of the first byte in the memory.
276 @param withLength The length of memory.
277 @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.
278 @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
279
280 static IOMemoryDescriptor * withAddress(void * address,
281 IOByteCount withLength,
282 IODirection withDirection);
283
284 #ifndef __LP64__
285 static IOMemoryDescriptor * withAddress(IOVirtualAddress address,
286 IOByteCount withLength,
287 IODirection withDirection,
288 task_t withTask) APPLE_KEXT_DEPRECATED; /* use withAddressRange() and prepare() instead */
289 #endif /* !__LP64__ */
290
291 /*! @function withPhysicalAddress
292 @abstract Create an IOMemoryDescriptor to describe one physical range.
293 @discussion This method creates and initializes an IOMemoryDescriptor for memory consisting of a single physical memory range.
294 @param address The physical address of the first byte in the memory.
295 @param withLength The length of memory.
296 @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.
297 @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
298
299 static IOMemoryDescriptor * withPhysicalAddress(
300 IOPhysicalAddress address,
301 IOByteCount withLength,
302 IODirection withDirection );
303
304 #ifndef __LP64__
305 static IOMemoryDescriptor * withRanges(IOVirtualRange * ranges,
306 UInt32 withCount,
307 IODirection withDirection,
308 task_t withTask,
309 bool asReference = false) APPLE_KEXT_DEPRECATED; /* use withAddressRanges() instead */
310 #endif /* !__LP64__ */
311
312 /*! @function withAddressRange
313 @abstract Create an IOMemoryDescriptor to describe one virtual range of the specified map.
314 @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.
315 @param address The virtual address of the first byte in the memory.
316 @param withLength The length of memory.
317 @param options
318 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.
319 @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.
320 @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
321
322 static IOMemoryDescriptor * withAddressRange(
323 mach_vm_address_t address,
324 mach_vm_size_t length,
325 IOOptionBits options,
326 task_t task);
327
328 /*! @function withAddressRanges
329 @abstract Create an IOMemoryDescriptor to describe one or more virtual ranges.
330 @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.
331 @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.
332 @param rangeCount The member count of the ranges array.
333 @param options
334 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.
335 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.
336 @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.
337 @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
338
339 static IOMemoryDescriptor * withAddressRanges(
340 IOAddressRange * ranges,
341 UInt32 rangeCount,
342 IOOptionBits options,
343 task_t task);
344
345 /*! @function withOptions
346 @abstract Master initialiser for all variants of memory descriptors.
347 @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.
348
349
350 @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.
351
352 @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.
353
354 @param offset Only used when options:type = UPL, in which case this field contains an offset for the memory within the buffers upl.
355
356 @param task Only used options:type = Virtual, The task each of the virtual ranges are mapped into.
357
358 @param options
359 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.
360 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.
361 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.
362 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.
363
364 @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.
365
366 @result The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure. */
367
368 static IOMemoryDescriptor *withOptions(void * buffers,
369 UInt32 count,
370 UInt32 offset,
371 task_t task,
372 IOOptionBits options,
373 IOMapper * mapper = kIOMapperSystem);
374
375 #ifndef __LP64__
376 static IOMemoryDescriptor * withPhysicalRanges(
377 IOPhysicalRange * ranges,
378 UInt32 withCount,
379 IODirection withDirection,
380 bool asReference = false) APPLE_KEXT_DEPRECATED; /* use withOptions() and kIOMemoryTypePhysical instead */
381 #endif /* !__LP64__ */
382
383 #ifndef __LP64__
384 static IOMemoryDescriptor * withSubRange(IOMemoryDescriptor *of,
385 IOByteCount offset,
386 IOByteCount length,
387 IODirection withDirection) APPLE_KEXT_DEPRECATED; /* use IOSubMemoryDescriptor::withSubRange() and kIOMemoryThreadSafe instead */
388 #endif /* !__LP64__ */
389
390 /*! @function withPersistentMemoryDescriptor
391 @abstract Copy constructor that generates a new memory descriptor if the backing memory for the same task's virtual address and length has changed.
392 @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.
393 @param originalMD The memory descriptor to be duplicated.
394 @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. */
395 static IOMemoryDescriptor *
396 withPersistentMemoryDescriptor(IOMemoryDescriptor *originalMD);
397
398 #ifndef __LP64__
399 // obsolete initializers
400 // - initWithOptions is the designated initializer
401 virtual bool initWithAddress(void * address,
402 IOByteCount withLength,
403 IODirection withDirection) APPLE_KEXT_DEPRECATED; /* use initWithOptions() instead */
404 virtual bool initWithAddress(IOVirtualAddress address,
405 IOByteCount withLength,
406 IODirection withDirection,
407 task_t withTask) APPLE_KEXT_DEPRECATED; /* use initWithOptions() instead */
408 virtual bool initWithPhysicalAddress(
409 IOPhysicalAddress address,
410 IOByteCount withLength,
411 IODirection withDirection ) APPLE_KEXT_DEPRECATED; /* use initWithOptions() instead */
412 virtual bool initWithRanges(IOVirtualRange * ranges,
413 UInt32 withCount,
414 IODirection withDirection,
415 task_t withTask,
416 bool asReference = false) APPLE_KEXT_DEPRECATED; /* use initWithOptions() instead */
417 virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
418 UInt32 withCount,
419 IODirection withDirection,
420 bool asReference = false) APPLE_KEXT_DEPRECATED; /* use initWithOptions() instead */
421 #endif /* __LP64__ */
422
423 /*! @function getDirection
424 @abstract Accessor to get the direction the memory descriptor was created with.
425 @discussion This method returns the direction the memory descriptor was created with.
426 @result The direction. */
427
428 virtual IODirection getDirection() const;
429
430 /*! @function getLength
431 @abstract Accessor to get the length of the memory descriptor (over all its ranges).
432 @discussion This method returns the total length of the memory described by the descriptor, ie. the sum of its ranges' lengths.
433 @result The byte count. */
434
435 virtual IOByteCount getLength() const;
436
437 /*! @function setTag
438 @abstract Set the tag for the memory descriptor.
439 @discussion This method sets the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
440 @param tag The tag. */
441
442 virtual void setTag( IOOptionBits tag );
443
444 /*! @function getTag
445 @abstract Accessor to the retrieve the tag for the memory descriptor.
446 @discussion This method returns the tag for the memory descriptor. Tag bits are not interpreted by IOMemoryDescriptor.
447 @result The tag. */
448
449 virtual IOOptionBits getTag( void );
450
451 /*! @function readBytes
452 @abstract Copy data from the memory descriptor's buffer to the specified buffer.
453 @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.
454 @param offset A byte offset into the memory descriptor's memory.
455 @param bytes The caller supplied buffer to copy the data to.
456 @param withLength The length of the data to copy.
457 @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. */
458
459 virtual IOByteCount readBytes(IOByteCount offset,
460 void * bytes, IOByteCount withLength);
461
462 /*! @function writeBytes
463 @abstract Copy data to the memory descriptor's buffer from the specified buffer.
464 @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.
465 @param offset A byte offset into the memory descriptor's memory.
466 @param bytes The caller supplied buffer to copy the data from.
467 @param withLength The length of the data to copy.
468 @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. */
469
470 virtual IOByteCount writeBytes(IOByteCount offset,
471 const void * bytes, IOByteCount withLength);
472
473 #ifndef __LP64__
474 virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
475 IOByteCount * length);
476 #endif /* !__LP64__ */
477
478 /*! @function getPhysicalAddress
479 @abstract Return the physical address of the first byte in the memory.
480 @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.
481 @result A physical address. */
482
483 IOPhysicalAddress getPhysicalAddress();
484
485 #ifndef __LP64__
486 virtual void * getVirtualSegment(IOByteCount offset,
487 IOByteCount * length) APPLE_KEXT_DEPRECATED; /* use map() and getVirtualAddress() instead */
488 #endif /* !__LP64__ */
489
490 /*! @function prepare
491 @abstract Prepare the memory for an I/O transfer.
492 @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.
493 @param forDirection The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
494 @result An IOReturn code. */
495
496 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone) = 0;
497
498 /*! @function complete
499 @abstract Complete processing of the memory after an I/O transfer finishes.
500 @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.
501 @param forDirection DEPRECATED The direction of the I/O just completed, or kIODirectionNone for the direction specified by the memory descriptor.
502 @result An IOReturn code. */
503
504 virtual IOReturn complete(IODirection forDirection = kIODirectionNone) = 0;
505
506 /*
507 * Mapping functions.
508 */
509
510 /*! @function createMappingInTask
511 @abstract Maps a IOMemoryDescriptor into a task.
512 @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.
513 @param intoTask Sets the target task for the mapping. Pass kernel_task for the kernel address space.
514 @param atAddress If a placed mapping is requested, atAddress specifies its address, and the kIOMapAnywhere should not be set. Otherwise, atAddress is ignored.
515 @param options Mapping options are defined in IOTypes.h,<br>
516 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>
517 kIOMapDefaultCache to inhibit the cache in I/O areas, kIOMapCopybackCache in general purpose RAM.<br>
518 kIOMapInhibitCache, kIOMapWriteThruCache, kIOMapCopybackCache to set the appropriate caching.<br>
519 kIOMapReadOnly to allow only read only accesses to the memory - writes will cause and access fault.<br>
520 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>
521 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>
522 @param offset Is a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default to map all the memory.
523 @param length Is the length of the mapping requested for a subset of the IOMemoryDescriptor. Zero is the default to map all the memory.
524 @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. */
525
526 IOMemoryMap * createMappingInTask(
527 task_t intoTask,
528 mach_vm_address_t atAddress,
529 IOOptionBits options,
530 mach_vm_size_t offset = 0,
531 mach_vm_size_t length = 0 );
532
533 #ifndef __LP64__
534 virtual IOMemoryMap * map(
535 task_t intoTask,
536 IOVirtualAddress atAddress,
537 IOOptionBits options,
538 IOByteCount offset = 0,
539 IOByteCount length = 0 ) APPLE_KEXT_DEPRECATED; /* use createMappingInTask() instead */
540 #endif /* !__LP64__ */
541
542 /*! @function map
543 @abstract Maps a IOMemoryDescriptor into the kernel map.
544 @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.
545 @param options Mapping options as in the full version of the createMappingInTask method, with kIOMapAnywhere assumed.
546 @result See the full version of the createMappingInTask method. */
547
548 virtual IOMemoryMap * map(
549 IOOptionBits options = 0 );
550
551 /*! @function setMapping
552 @abstract Establishes an already existing mapping.
553 @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.
554 @param task Address space in which the mapping exists.
555 @param mapAddress Virtual address of the mapping.
556 @param options Caching and read-only attributes of the mapping.
557 @result A IOMemoryMap object created to represent the mapping. */
558
559 virtual IOMemoryMap * setMapping(
560 task_t task,
561 IOVirtualAddress mapAddress,
562 IOOptionBits options = 0 );
563
564 // Following methods are private implementation
565
566 #ifdef __LP64__
567 virtual
568 #endif /* __LP64__ */
569 IOReturn redirect( task_t safeTask, bool redirect );
570
571 IOReturn handleFault(
572 void * pager,
573 vm_map_t addressMap,
574 mach_vm_address_t address,
575 mach_vm_size_t sourceOffset,
576 mach_vm_size_t length,
577 IOOptionBits options );
578
579 virtual IOMemoryMap * makeMapping(
580 IOMemoryDescriptor * owner,
581 task_t intoTask,
582 IOVirtualAddress atAddress,
583 IOOptionBits options,
584 IOByteCount offset,
585 IOByteCount length );
586
587 protected:
588 virtual void addMapping(
589 IOMemoryMap * mapping );
590
591 virtual void removeMapping(
592 IOMemoryMap * mapping );
593
594 virtual IOReturn doMap(
595 vm_map_t addressMap,
596 IOVirtualAddress * atAddress,
597 IOOptionBits options,
598 IOByteCount sourceOffset = 0,
599 IOByteCount length = 0 );
600
601 virtual IOReturn doUnmap(
602 vm_map_t addressMap,
603 IOVirtualAddress logical,
604 IOByteCount length );
605 };
606
607 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
608
609 /*! @class IOMemoryMap : public OSObject
610 @abstract A class defining common methods for describing a memory mapping.
611 @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. */
612
613 class IOMemoryMap : public OSObject
614 {
615 OSDeclareDefaultStructors(IOMemoryMap)
616 #ifdef XNU_KERNEL_PRIVATE
617 public:
618 IOMemoryDescriptor * fMemory;
619 IOMemoryMap * fSuperMap;
620 mach_vm_size_t fOffset;
621 mach_vm_address_t fAddress;
622 mach_vm_size_t fLength;
623 task_t fAddressTask;
624 vm_map_t fAddressMap;
625 IOOptionBits fOptions;
626 upl_t fRedirUPL;
627 ipc_port_t fRedirEntry;
628 IOMemoryDescriptor * fOwner;
629 uint8_t fUserClientUnmap;
630 #endif /* XNU_KERNEL_PRIVATE */
631
632 protected:
633 virtual void taggedRelease(const void *tag = 0) const;
634 virtual void free();
635
636 public:
637 /*! @function getVirtualAddress
638 @abstract Accessor to the virtual address of the first byte in the mapping.
639 @discussion This method returns the virtual address of the first byte in the mapping.
640 @result A virtual address. */
641
642 virtual IOVirtualAddress getVirtualAddress();
643
644 /*! @function getPhysicalSegment
645 @abstract Break a mapping into its physically contiguous segments.
646 @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.
647 @param offset A byte offset into the mapping whose physical address to return.
648 @param length If non-zero, getPhysicalSegment will store here the length of the physically contiguous segement at the given offset.
649 @result A physical address, or zero if the offset is beyond the length of the mapping. */
650
651 #ifdef __LP64__
652 virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
653 IOByteCount * length,
654 IOOptionBits options = 0);
655 #else /* !__LP64__ */
656 virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
657 IOByteCount * length);
658 #endif /* !__LP64__ */
659
660 /*! @function getPhysicalAddress
661 @abstract Return the physical address of the first byte in the mapping.
662 @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.
663 @result A physical address. */
664
665 IOPhysicalAddress getPhysicalAddress();
666
667 /*! @function getLength
668 @abstract Accessor to the length of the mapping.
669 @discussion This method returns the length of the mapping.
670 @result A byte count. */
671
672 virtual IOByteCount getLength();
673
674 /*! @function getAddressTask
675 @abstract Accessor to the task of the mapping.
676 @discussion This method returns the mach task the mapping exists in.
677 @result A mach task_t. */
678
679 virtual task_t getAddressTask();
680
681 /*! @function getMemoryDescriptor
682 @abstract Accessor to the IOMemoryDescriptor the mapping was created from.
683 @discussion This method returns the IOMemoryDescriptor the mapping was created from.
684 @result An IOMemoryDescriptor reference, which is valid while the IOMemoryMap object is retained. It should not be released by the caller. */
685
686 virtual IOMemoryDescriptor * getMemoryDescriptor();
687
688 /*! @function getMapOptions
689 @abstract Accessor to the options the mapping was created with.
690 @discussion This method returns the options to IOMemoryDescriptor::map the mapping was created with.
691 @result Options for the mapping, including cache settings. */
692
693 virtual IOOptionBits getMapOptions();
694
695 /*! @function unmap
696 @abstract Force the IOMemoryMap to unmap, without destroying the object.
697 @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.
698 @result An IOReturn code. */
699
700 virtual IOReturn unmap();
701
702 virtual void taskDied();
703
704 /*! @function redirect
705 @abstract Replace the memory mapped in a process with new backing memory.
706 @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.
707 @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.
708 @param options Mapping options are defined in IOTypes.h, and are documented in IOMemoryDescriptor::map()
709 @param offset As with IOMemoryDescriptor::map(), a beginning offset into the IOMemoryDescriptor's memory where the mapping starts. Zero is the default.
710 @result An IOReturn code. */
711
712 #ifndef __LP64__
713 // For 32 bit XNU, there is a 32 bit (IOByteCount) and a 64 bit (mach_vm_size_t) interface;
714 // for 64 bit, these fall together on the 64 bit one.
715 virtual IOReturn redirect(IOMemoryDescriptor * newBackingMemory,
716 IOOptionBits options,
717 IOByteCount offset = 0);
718 #endif
719 virtual IOReturn redirect(IOMemoryDescriptor * newBackingMemory,
720 IOOptionBits options,
721 mach_vm_size_t offset = 0);
722
723 #ifdef __LP64__
724 inline mach_vm_address_t getAddress() __attribute__((always_inline));
725 inline mach_vm_size_t getSize() __attribute__((always_inline));
726 #else /* !__LP64__ */
727 virtual mach_vm_address_t getAddress();
728 virtual mach_vm_size_t getSize();
729 #endif /* !__LP64__ */
730
731 #ifdef XNU_KERNEL_PRIVATE
732 // for IOMemoryDescriptor use
733 IOMemoryMap * copyCompatible( IOMemoryMap * newMapping );
734
735 bool init(
736 task_t intoTask,
737 mach_vm_address_t toAddress,
738 IOOptionBits options,
739 mach_vm_size_t offset,
740 mach_vm_size_t length );
741
742 bool setMemoryDescriptor(IOMemoryDescriptor * _memory, mach_vm_size_t _offset);
743
744 IOReturn redirect(
745 task_t intoTask, bool redirect );
746
747 IOReturn userClientUnmap();
748 #endif /* XNU_KERNEL_PRIVATE */
749
750 OSMetaClassDeclareReservedUnused(IOMemoryMap, 0);
751 OSMetaClassDeclareReservedUnused(IOMemoryMap, 1);
752 OSMetaClassDeclareReservedUnused(IOMemoryMap, 2);
753 OSMetaClassDeclareReservedUnused(IOMemoryMap, 3);
754 OSMetaClassDeclareReservedUnused(IOMemoryMap, 4);
755 OSMetaClassDeclareReservedUnused(IOMemoryMap, 5);
756 OSMetaClassDeclareReservedUnused(IOMemoryMap, 6);
757 OSMetaClassDeclareReservedUnused(IOMemoryMap, 7);
758 };
759
760 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
761 #ifdef XNU_KERNEL_PRIVATE
762 // Also these flags should not overlap with the options to
763 // IOMemoryDescriptor::initWithRanges(... IOOptionsBits options);
764 enum {
765 _kIOMemorySourceSegment = 0x00002000
766 };
767 #endif /* XNU_KERNEL_PRIVATE */
768
769 #if !defined(__LP64) || defined(_IOMEMORYDESCRIPTOR_INTERNAL_)
770
771 // The following classes are private implementation of IOMemoryDescriptor - they
772 // should not be referenced directly, just through the public API's in the
773 // IOMemoryDescriptor class. For example, an IOGeneralMemoryDescriptor instance
774 // might be created by IOMemoryDescriptor::withAddressRange(), but there should be
775 // no need to reference as anything but a generic IOMemoryDescriptor *.
776
777 class IOGeneralMemoryDescriptor : public IOMemoryDescriptor
778 {
779 OSDeclareDefaultStructors(IOGeneralMemoryDescriptor);
780
781 public:
782 union Ranges {
783 IOVirtualRange *v;
784 IOAddressRange *v64;
785 IOPhysicalRange *p;
786 void *uio;
787 };
788 protected:
789 Ranges _ranges;
790 unsigned _rangesCount; /* number of address ranges in list */
791 #ifndef __LP64__
792 bool _rangesIsAllocated; /* is list allocated by us? */
793 #endif /* !__LP64__ */
794
795 task_t _task; /* task where all ranges are mapped to */
796
797 union {
798 IOVirtualRange v;
799 IOPhysicalRange p;
800 } _singleRange; /* storage space for a single range */
801
802 unsigned _wireCount; /* number of outstanding wires */
803
804 #ifndef __LP64__
805 uintptr_t _cachedVirtualAddress;
806
807 IOPhysicalAddress _cachedPhysicalAddress;
808 #endif /* !__LP64__ */
809
810 bool _initialized; /* has superclass been initialized? */
811
812 public:
813 virtual void free();
814
815 virtual IOReturn dmaCommandOperation(DMACommandOps op, void *vData, UInt dataSize) const;
816
817 virtual uint64_t getPreparationID( void );
818
819 private:
820
821 #ifndef __LP64__
822 virtual void setPosition(IOByteCount position);
823 virtual void mapIntoKernel(unsigned rangeIndex);
824 virtual void unmapFromKernel();
825 #endif /* !__LP64__ */
826
827 // Internal APIs may be made virtual at some time in the future.
828 IOReturn wireVirtual(IODirection forDirection);
829 void *createNamedEntry();
830
831 // Internal
832 OSData * _memoryEntries;
833 unsigned int _pages;
834 ppnum_t _highestPage;
835 uint32_t __iomd_reservedA;
836 uint32_t __iomd_reservedB;
837
838 IOLock * _prepareLock;
839
840 public:
841 /*
842 * IOMemoryDescriptor required methods
843 */
844
845 // Master initaliser
846 virtual bool initWithOptions(void * buffers,
847 UInt32 count,
848 UInt32 offset,
849 task_t task,
850 IOOptionBits options,
851 IOMapper * mapper = kIOMapperSystem);
852
853 #ifndef __LP64__
854 // Secondary initialisers
855 virtual bool initWithAddress(void * address,
856 IOByteCount withLength,
857 IODirection withDirection) APPLE_KEXT_DEPRECATED;
858
859 virtual bool initWithAddress(IOVirtualAddress address,
860 IOByteCount withLength,
861 IODirection withDirection,
862 task_t withTask) APPLE_KEXT_DEPRECATED;
863
864 virtual bool initWithPhysicalAddress(
865 IOPhysicalAddress address,
866 IOByteCount withLength,
867 IODirection withDirection ) APPLE_KEXT_DEPRECATED;
868
869 virtual bool initWithRanges( IOVirtualRange * ranges,
870 UInt32 withCount,
871 IODirection withDirection,
872 task_t withTask,
873 bool asReference = false) APPLE_KEXT_DEPRECATED;
874
875 virtual bool initWithPhysicalRanges(IOPhysicalRange * ranges,
876 UInt32 withCount,
877 IODirection withDirection,
878 bool asReference = false) APPLE_KEXT_DEPRECATED;
879
880 virtual addr64_t getPhysicalSegment64( IOByteCount offset,
881 IOByteCount * length ) APPLE_KEXT_DEPRECATED;
882
883 virtual IOPhysicalAddress getPhysicalSegment(IOByteCount offset,
884 IOByteCount * length);
885
886 virtual IOPhysicalAddress getSourceSegment(IOByteCount offset,
887 IOByteCount * length) APPLE_KEXT_DEPRECATED;
888
889 virtual void * getVirtualSegment(IOByteCount offset,
890 IOByteCount * length) APPLE_KEXT_DEPRECATED;
891 #endif /* !__LP64__ */
892
893 virtual IOReturn setPurgeable( IOOptionBits newState,
894 IOOptionBits * oldState );
895
896 virtual addr64_t getPhysicalSegment( IOByteCount offset,
897 IOByteCount * length,
898 #ifdef __LP64__
899 IOOptionBits options = 0 );
900 #else /* !__LP64__ */
901 IOOptionBits options );
902 #endif /* !__LP64__ */
903
904 virtual IOReturn prepare(IODirection forDirection = kIODirectionNone);
905
906 virtual IOReturn complete(IODirection forDirection = kIODirectionNone);
907
908 virtual IOReturn doMap(
909 vm_map_t addressMap,
910 IOVirtualAddress * atAddress,
911 IOOptionBits options,
912 IOByteCount sourceOffset = 0,
913 IOByteCount length = 0 );
914
915 virtual IOReturn doUnmap(
916 vm_map_t addressMap,
917 IOVirtualAddress logical,
918 IOByteCount length );
919
920 virtual bool serialize(OSSerialize *s) const;
921
922 // Factory method for cloning a persistent IOMD, see IOMemoryDescriptor
923 static IOMemoryDescriptor *
924 withPersistentMemoryDescriptor(IOGeneralMemoryDescriptor *originalMD);
925
926 };
927
928 #endif /* !defined(__LP64) || defined(_IOMEMORYDESCRIPTOR_INTERNAL_) */
929
930 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
931
932 #ifdef __LP64__
933 mach_vm_address_t IOMemoryMap::getAddress()
934 {
935 return (getVirtualAddress());
936 }
937
938 mach_vm_size_t IOMemoryMap::getSize()
939 {
940 return (getLength());
941 }
942 #else /* !__LP64__ */
943 #include <IOKit/IOSubMemoryDescriptor.h>
944 #endif /* !__LP64__ */
945
946 /* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
947
948 #endif /* !_IOMEMORYDESCRIPTOR_H */