MIPS: DMA: Fix computation of DMA flags from device's coherent_dma_mask.

This only matters for ISA devices with a 24-bit DMA limit or for devices
with a 32-bit DMA limit on systems with ZONE_DMA32 enabled.  The latter
currently only affects 32-bit PCI cards on Sibyte-based systems with more
than 1GB RAM installed.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index 7ba8908..469d401 100644 (file)
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -44,27 +44,39 @@ static inline int cpu_is_noncoherent_r10000(struct device *dev)
 
 static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
 {
+       gfp_t dma_flag;
+
        /* ignore region specifiers */
        gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
 
-#ifdef CONFIG_ZONE_DMA
+#ifdef CONFIG_ISA
        if (dev == NULL)
-               gfp |= __GFP_DMA;
-       else if (dev->coherent_dma_mask < DMA_BIT_MASK(24))
-               gfp |= __GFP_DMA;
+               dma_flag = __GFP_DMA;
        else
 #endif
-#ifdef CONFIG_ZONE_DMA32
+#if defined(CONFIG_ZONE_DMA32) && defined(CONFIG_ZONE_DMA)
             if (dev->coherent_dma_mask < DMA_BIT_MASK(32))
-               gfp |= __GFP_DMA32;
+                       dma_flag = __GFP_DMA;
+       else if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+                       dma_flag = __GFP_DMA32;
+       else
+#endif
+#if defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_ZONE_DMA)
+            if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+               dma_flag = __GFP_DMA32;
+       else
+#endif
+#if defined(CONFIG_ZONE_DMA) && !defined(CONFIG_ZONE_DMA32)
+            if (dev->coherent_dma_mask < DMA_BIT_MASK(64))
+               dma_flag = __GFP_DMA;
        else
 #endif
-               ;
+               dma_flag = 0;
 
        /* Don't invoke OOM killer */
        gfp |= __GFP_NORETRY;
 
-       return gfp;
+       return gfp | dma_flag;
 }
 
 void *dma_alloc_noncoherent(struct device *dev, size_t size,