Can a driver create a VMA?

[ttabi2@xxxxxxxxxxx]

I have a driver that calls get_user_pages() to map and lock a memory 
buffer from an app.  Unfortunately, the locking part doesn't work very 
well.  The swapper daemon will still swap out the page.  I have a test 
case that uses our custom hardware and DMA to prove it, but we're 
working on a more portable test case that we can send to the kernel 
developers.  In the meantime, I need to work on an alternative.

Using sys_mlock(), we're able to lock the memory buffer down, but this 
is not an ideal solution.  What I'd like to do is create a new VMA for 
just the memory buffer, and then lock that VMA.  Locking the VMA is what 
really locks the buffer.

I know the get_user_pages() returns an array of VMAs, but those VMAs 
most likely include other pages, and I don't want to lock any of those. 
 So what I would like to do is create a brand new VMA, assign it to the 
application process, and then associate all of the pages from the memory 
buffer to that VMA.

Is it possible for me to do all that from within a kernel module?  I've 
done quite a few searches, and the only way I've found to do that is 
with another system call, which I'm trying to avoid.

--
Timur Tabi

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