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Introduction to DMA in Windows Driver Framework

[Applies to KMDF only]

On Windows 7 and earlier, Kernel-Mode Driver Framework (KMDF) supports only bus-master direct memory access (DMA) devices. Such devices contain their own DMA controllers.

On System on a Chip (SoC)–based platforms running Windows 8 and later, the framework also supports system-mode DMA, in which multiple devices share a single multichannel DMA controller.

The framework's DMA support consists of:

  • A set of framework DMA objects and methods that drivers use to convert I/O requests into DMA operations.

  • A set of driver-supplied event callback functions that configure the device's DMA behavior as different events occur.

The framework supports both single packet and scatter/gather DMA transfers. It also supports the use of common buffers.

On SoC-based platforms running Windows 8 and later, the framework supports single-packet system-mode DMA transfers. For more information, see Supporting System-Mode DMA.

The framework does not support system-mode DMA transfers on PC-based platforms.

Enabling DMA Remapping for device drivers