[PATCH 19/33] dma-mapping: warn when there is no coherent_dma_mask
From: hch@lst.de (Christoph Hellwig)
Date: 2018-01-10 08:01:41
Also in:
linux-alpha, linux-arch, linux-iommu, linux-mips, linux-s390, linux-sh, linuxppc-dev, lkml, sparclinux
Subsystem:
dma mapping helpers, the rest · Maintainers:
Marek Szyprowski, Linus Torvalds
These days all devices should have a DMA coherent mask, and most dma_ops implementations rely on that fact. But just to be sure add an assert to ring the warning bell if that is not the case. Signed-off-by: Christoph Hellwig <hch@lst.de> --- include/linux/dma-mapping.h | 1 + 1 file changed, 1 insertion(+)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index d84951865be7..9f28b2fa329e 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h@@ -513,6 +513,7 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size, void *cpu_addr; BUG_ON(!ops); + WARN_ON_ONCE(!dev->coherent_dma_mask); if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr)) return cpu_addr;
--
2.14.2