From 58edb515724f9e63e569536d01ac8d8f8ddb367a Mon Sep 17 00:00:00 2001 From: Nicolas Pitre Date: Tue, 9 Sep 2008 15:54:13 -0400 Subject: [ARM] make page_to_dma() highmem aware If a machine class has a custom __virt_to_bus() implementation then it must provide a __arch_page_to_dma() implementation as well which is _not_ based on page_address() to support highmem. This patch fixes existing __arch_page_to_dma() and provide a default implementation otherwise. The default implementation for highmem is based on __pfn_to_bus() which is defined only when no custom __virt_to_bus() is provided by the machine class. That leaves only ebsa110 and footbridge which cannot support highmem until they provide their own __arch_page_to_dma() implementation. But highmem support on those legacy platforms with limited memory is certainly not a priority. Signed-off-by: Nicolas Pitre --- arch/arm/common/dmabounce.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/arm/common/dmabounce.c') diff --git a/arch/arm/common/dmabounce.c b/arch/arm/common/dmabounce.c index f030f0775be7..734ac9135998 100644 --- a/arch/arm/common/dmabounce.c +++ b/arch/arm/common/dmabounce.c @@ -25,6 +25,7 @@ #include #include #include +#include #include #include #include @@ -349,6 +350,12 @@ dma_addr_t dma_map_page(struct device *dev, struct page *page, BUG_ON(!valid_dma_direction(dir)); + if (PageHighMem(page)) { + dev_err(dev, "DMA buffer bouncing of HIGHMEM pages " + "is not supported\n"); + return ~0; + } + return map_single(dev, page_address(page) + offset, size, dir); } EXPORT_SYMBOL(dma_map_page); -- cgit v1.2.3