MIPS: fix DMA contiguous allocation
authorQais Yousef <qais.yousef@imgtec.com>
Fri, 11 Dec 2015 21:41:09 +0000 (13:41 -0800)
committerLinus Torvalds <torvalds@linux-foundation.org>
Sat, 12 Dec 2015 18:15:34 +0000 (10:15 -0800)
Recent changes to how GFP_ATOMIC is defined seems to have broken the
condition to use mips_alloc_from_contiguous() in
mips_dma_alloc_coherent().

I couldn't bottom out the exact change but I think it's this commit
d0164adc89f6 ("mm, page_alloc: distinguish between being unable to
sleep, unwilling to sleep and avoiding waking kswapd").

GFP_ATOMIC has multiple bits set and the check for !(gfp & GFP_ATOMIC)
isn't enough.

The reason behind this condition is to check whether we can potentially
do a sleeping memory allocation.  Use gfpflags_allow_blocking() instead
which should be more robust.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
arch/mips/mm/dma-default.c

index d8117be729a20ee26d2df8bb42a6f58b9670f513..730d394ce5f017991146084f9df53794242c970d 100644 (file)
@@ -145,7 +145,7 @@ static void *mips_dma_alloc_coherent(struct device *dev, size_t size,
 
        gfp = massage_gfp_flags(dev, gfp);
 
-       if (IS_ENABLED(CONFIG_DMA_CMA) && !(gfp & GFP_ATOMIC))
+       if (IS_ENABLED(CONFIG_DMA_CMA) && gfpflags_allow_blocking(gfp))
                page = dma_alloc_from_contiguous(dev,
                                        count, get_order(size));
        if (!page)