Create an IOMemoryDescriptor to describe one or more virtual 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.
The member count of the ranges array.
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. 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.
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.
The created IOMemoryDescriptor on success, to be released by the caller, or zero on failure.
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.