As to whether DMA can be used to copy memory to memory, you can refer to the answer below http://stackoverflow.com/ques...
As for copying from kernel space to user space, you also need to consider issues such as virtual and real address conversion and cache consistency between DMA and CPU. Considering all aspects, the gain may outweigh the loss.
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As to whether DMA can be used to copy memory to memory, you can refer to the answer below
http://stackoverflow.com/ques...
As for copying from kernel space to user space, you also need to consider issues such as virtual and real address conversion and cache consistency between DMA and CPU. Considering all aspects, the gain may outweigh the loss.
Some questions are about whether the quality is good
https://en.wikipedia.org/wiki...
First of all, we must understand what DMA is