From 28b24c1fc8c22cabe5b8a16ffe6a61dfce51a1f2 Mon Sep 17 00:00:00 2001 From: Sasha Levin Date: Tue, 14 Apr 2015 15:44:57 -0700 Subject: mm: cma: debugfs interface I've noticed that there is no interfaces exposed by CMA which would let me fuzz what's going on in there. This small patchset exposes some information out to userspace, plus adds the ability to trigger allocation and freeing from userspace. This patch (of 3): Implement a simple debugfs interface to expose information about CMA areas in the system. Useful for testing/sanity checks for CMA since it was impossible to previously retrieve this information in userspace. Signed-off-by: Sasha Levin Acked-by: Joonsoo Kim Cc: Marek Szyprowski Cc: Laura Abbott Cc: Konrad Rzeszutek Wilk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/cma.h | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) create mode 100644 mm/cma.h (limited to 'mm/cma.h') diff --git a/mm/cma.h b/mm/cma.h new file mode 100644 index 000000000000..4141887bbfb0 --- /dev/null +++ b/mm/cma.h @@ -0,0 +1,20 @@ +#ifndef __MM_CMA_H__ +#define __MM_CMA_H__ + +struct cma { + unsigned long base_pfn; + unsigned long count; + unsigned long *bitmap; + unsigned int order_per_bit; /* Order of pages represented by one bit */ + struct mutex lock; +}; + +extern struct cma cma_areas[MAX_CMA_AREAS]; +extern unsigned cma_area_count; + +static unsigned long cma_bitmap_maxno(struct cma *cma) +{ + return cma->count >> cma->order_per_bit; +} + +#endif -- cgit