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I am trying to understand the dma buf framework in linux kernel and going through this article http://lwn.net/Articles/489703/ which says

Userspace entity requests for a file-descriptor (fd) which is a handle to the anonymous file associated with the buffer. It can then share the fd with other drivers and/or processes.

My question is, "any fd allocated is unique to a process. so, i think if we pass this to another process(passed fd is invalid in this process context) how can it get the handle to dma buffer?"

Ravi Chandra
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  • @mgalgs I would like to know if it is really possible to share the fd of dma buffer with the other user space linux processes? – user1020828 Jul 01 '23 at 16:41

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The way it works is that you have to use a special fd-sharing mechanism like unix domain sockets or binder.

mgalgs
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