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 <sasha.levin@oracle.com>
Acked-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Laura Abbott <lauraa@codeaurora.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/mm/cma.h b/mm/cma.h
index 4141887bbfb0..1132d733556d 100644
--- a/mm/cma.h
+++ b/mm/cma.h
@@ -7,6 +7,10 @@ struct cma {
 	unsigned long   *bitmap;
 	unsigned int order_per_bit; /* Order of pages represented by one bit */
 	struct mutex    lock;
+#ifdef CONFIG_CMA_DEBUGFS
+	struct hlist_head mem_head;
+	spinlock_t mem_head_lock;
+#endif
 };
 
 extern struct cma cma_areas[MAX_CMA_AREAS];