[PATCH 24/33] powerpc/dma: fix an off-by-one in dma_capable

Christoph Hellwig
2018-10-09T13:26:25Z

We need to compare the last byte in the dma range and not the one after it
for the bus_dma_mask, just like we do for the regular dma_mask. Fix this
cleanly by merging the two comparisms into one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/powerpc/include/asm/dma-direct.h | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/include/asm/dma-direct.h b/arch/powerpc/include/asm/dma-direct.h
index e00ab5d0612d..92d8aed86422 100644
--- a/arch/powerpc/include/asm/dma-direct.h
+++ b/arch/powerpc/include/asm/dma-direct.h
@@ -4,15 +4,11 @@

static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
{
-#ifdef CONFIG_SWIOTLB
- if (dev->bus_dma_mask && addr + size > dev->bus_dma_mask)
- return false;
-#endif
-
if (!dev->dma_mask)
return false;

- return addr + size - 1 <= *dev->dma_mask;
+ return addr + size - 1 <=
+ min_not_zero(*dev->dma_mask, dev->bus_dma_mask);
}

static inline dma_addr_t __phys_to_dma(struct device *dev, phys_addr_t paddr)
--
2.19.0