Hi,

I need some assistance handling a large memory segment of a user process.

The user calls the kernel with a address and a length of it's own memory. My 
driver will lock this memory using get_user_pages(). This memory is used as 
DMA buffer directly from or to user processes.

Everything works fine that far: allocating, DMA mapping, DMA transfers. But I 
currently can't get rid of the buffer again. Which function would help me to 
get all pages unlocked once the buffer isn't needed anymore?

Is it enough to simply call sys_munlock() from the release and cleanup 
functions?

There are no plans to share these mappings between different processes.

Greetings,

Eike