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SD_HOST_ALLOC_FREE_DMA_BUFFER (Compact 2013)

  • Article

3/26/2014

This structure is used to allocate and de-allocate a direct memory access (DMA) buffer from the secure digital (SD) card host. This structure can only be used when the SD host controller driver supports DMA. SD_HOST_ALLOC_FREE_DMA_BUFFER is also used to define the PHYS_BUFF_LIST structure when making an SD bus request with SDBusRequestEx and SDSynchronousBusRequestEx.

Syntax

typedef struct {
  ULONG Length;
  BOOLEAN CacheEnabled;
  PVOID VirtualAddress;
  PHYSICAL_ADDRESS LogicalAddress;
}SD_HOST_ALLOC_FREE_DMA_BUFFER, *PSD_HOST_ALLOC_FREE_DMA_BUFFER;

Members

  • Length
    The length, in bytes, of the buffer.
  • CacheEnabled
    Indicates whether the buffer allocation is cached or uncached.
  • VirtualAddress
    Pointer to virtual address buffer.
  • LogicalAddress
    Pointer to the logical address buffer.

Requirements

Header

sdcardddk.h

See Also

Reference

Secure Digital (SD) Card Driver Structures