//初始化用于DMA编程的三个对象
NTSTATUS status;
PDEVICE_CONTEXT pDeviceContext;
WDF_DMA_ENABLER_CONFIG dmaConfig = {0};
WDFDMAENABLER DmaEnabler;
PAGED_CODE();
pDeviceContext = GetDeviceContext(Device);
KdPrint(("自动获取边界大小:[%d]\n", WdfDeviceGetAlignmentRequirement(Device)));
//设置DMA数据缓冲区地址边界：16字节对齐
WdfDeviceSetAlignmentRequirement(Device, FILE_OCTA_ALIGNMENT);
//创建一个DMA适配器
dmaConfig.Size = sizeof(dmaConfig);
WDF_DMA_ENABLER_CONFIG_INIT(&dmaConfig,
WdfDmaProfileScatterGather64Duplex,
MAXNLEN);
status = WdfDmaEnablerCreate(Device,
&dmaConfig,
WDF_NO_OBJECT_ATTRIBUTES,
&DmaEnabler);
if (!NT_SUCCESS(status)) {
if (status == STATUS_INVALID_PARAMETER) {
KdPrint(("检测到无效参数\n"));
}
else if (status == STATUS_INSUFFICIENT_RESOURCES) {
KdPrint(("内存不足，无法构造新的 DMA 启用器对象\n"));
}
else if(status == STATUS_INFO_LENGTH_MISMATCH) {
KdPrint(("WDF_DMA_ENABLER_CONFIG结构的大小不正确\n"));
}else if(status == STATUS_NOT_SUPPORTED) {
KdPrint((" 驱动程序在早于 Windows 8 的操作系统上请求了 DMA 版本 3\n"));
}
else {
KdPrint(("DMA创建失败:[%d]\n",status));
}
return status;
}
