iokit/IOKit/IOMemoryCursor.h

42 specific memory cursors must inherit from, but a memory cursor can be created without a specific format subclass by just providing a segment function to the initializers.  This class does the difficult stuff of dividing a memory descriptor into a physical scatter/gather list appropriate for the target hardware.
136     @abstract Generates a physical scatter/gather list given a memory descriptor.
137     @discussion Generates a list of physical segments from the given memory descriptor, relative to the current position of the descriptor.
138     @param descriptor IOMemoryDescriptor that describes the data associated with an I/O request.
139     @param fromPosition Starting location of the I/O within a memory descriptor.
144     @result If the descriptor is exhausted of memory, a zero is returned, otherwise the number of segments that were filled in is returned.
147 				      IOMemoryDescriptor *descriptor,
209     @abstract Generates a CPU natural physical scatter/gather list given a memory descriptor.
210     @discussion Generates a list of physical segments from the given memory descriptor, relative to the current position of the descriptor.  Wraps IOMemoryCursor::genPhysicalSegments.
211     @param descriptor IOMemoryDescriptor that describes the data associated with an I/O request.
212     @param fromPosition Starting location of the I/O within a memory descriptor.
217     @result If the descriptor is exhausted of memory, a zero is returned, otherwise the number of segments that were filled in is returned.
219     virtual UInt32 getPhysicalSegments(IOMemoryDescriptor *descriptor,
226 	return genPhysicalSegments(descriptor, fromPosition, segments,
285     @abstract Generates a big endian physical scatter/gather list given a memory descriptor.
286     @discussion Generates a list of physical segments from the given memory descriptor, relative to the current position of the descriptor.  Wraps IOMemoryCursor::genPhysicalSegments.
287     @param descriptor IOMemoryDescriptor that describes the data associated with an I/O request.
288     @param fromPosition Starting location of the I/O within a memory descriptor.
293     @result If the descriptor is exhausted of memory, a zero is returned, otherwise the number of segments that were filled in is returned.
295     virtual UInt32 getPhysicalSegments(IOMemoryDescriptor * descriptor,
302 	return genPhysicalSegments(descriptor, fromPosition, segments,
359     @abstract Generates a little endian physical scatter/gather list given a memory descriptor.
360     @discussion Generates a list of physical segments from the given memory descriptor, relative to the current position of the descriptor.  Wraps IOMemoryCursor::genPhysicalSegments.
361     @param descriptor IOMemoryDescriptor that describes the data associated with an I/O request.
362     @param fromPosition Starting location of the I/O within a memory descriptor.
367     @result If the descriptor is exhausted of memory, a zero is returned, otherwise the number of segments that were filled in is returned.
369     virtual UInt32 getPhysicalSegments(IOMemoryDescriptor * descriptor,
376 	return genPhysicalSegments(descriptor, fromPosition, segments,