Hello I am writing a driver to operation with the dma-buf, a problem I meet is that a dma-buf maybe closed by the other driver or userspace application, then the same number of the file descriptor will be assigned with the other thing, its private data is different. I watch what the drm system do. The drm system doesn't use the file descriptor but the its private data (from dma_buf_get()) to check whether it is the same buffer. Is there a reference in the file descriptor? And is there a way to increase the reference to a file descriptor. I have designed a way to track the usage of the dma-buf of my driver, there is not a problem for the driver to release them. But I just want the new dma-buf is assigned with new file descriptor number, not re-use the closed one. Thank you.