mm: cma: allocation trigger

mm: cma: allocation trigger

Provides a userspace interface to trigger a CMA allocation.

Usage:

        echo [pages] > alloc

This would provide testing/fuzzing access to the CMA allocation paths.

Signed-off-by: Sasha Levin <[email protected]>
Acked-by: Joonsoo Kim <[email protected]>
Cc: Marek Szyprowski <[email protected]>
Cc: Laura Abbott <[email protected]>
Cc: Konrad Rzeszutek Wilk <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>