Data copying method, direct memory access controller and computer system

The present invention provides a data copying method, a direction memory access controller and a computer system. The data copying method of embodiments of the present invention comprises the steps that the direct memory access (DMA) controller reads target data from a storage space corresponding to a source physical address of the target data by using an accelerator coherency port (ACP), wherein the storage space corresponding to the source physical address comprises a first buffer region; and the DMA controller stores the target data in a storage space corresponding to a destination physical address of the target data by using the ACP, wherein the storage space corresponding to the destination physical address comprises a second buffer region. Through adoption of the method, the center process unit (CPU) usage is lowered.