From aafe4dbed0bf6cbdb2e9f03e1d42f8a540d8541d Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Wed, 13 May 2009 22:56:33 +0000 Subject: asm-generic: add generic versions of common headers These are all kernel internal interfaces that get copied around a lot. In most cases, architectures can provide their own optimized versions, but these generic versions can work as well. I have tried to use the most common contents of each header to allow existing architectures to migrate easily. Thanks to Remis for suggesting a number of cleanups. Signed-off-by: Remis Lima Baima Signed-off-by: Arnd Bergmann --- include/asm-generic/scatterlist.h | 43 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) create mode 100644 include/asm-generic/scatterlist.h (limited to 'include/asm-generic/scatterlist.h') diff --git a/include/asm-generic/scatterlist.h b/include/asm-generic/scatterlist.h new file mode 100644 index 000000000000..8b9454496a7c --- /dev/null +++ b/include/asm-generic/scatterlist.h @@ -0,0 +1,43 @@ +#ifndef __ASM_GENERIC_SCATTERLIST_H +#define __ASM_GENERIC_SCATTERLIST_H + +#include + +struct scatterlist { +#ifdef CONFIG_DEBUG_SG + unsigned long sg_magic; +#endif + unsigned long page_link; + unsigned int offset; + unsigned int length; + dma_addr_t dma_address; + unsigned int dma_length; +}; + +/* + * These macros should be used after a dma_map_sg call has been done + * to get bus addresses of each of the SG entries and their lengths. + * You should only work with the number of sg entries pci_map_sg + * returns, or alternatively stop on the first sg_dma_len(sg) which + * is 0. + */ +#define sg_dma_address(sg) ((sg)->dma_address) +#ifndef sg_dma_len +/* + * Normally, you have an iommu on 64 bit machines, but not on 32 bit + * machines. Architectures that are differnt should override this. + */ +#if __BITS_PER_LONG == 64 +#define sg_dma_len(sg) ((sg)->dma_length) +#else +#define sg_dma_len(sg) ((sg)->length) +#endif /* 64 bit */ +#endif /* sg_dma_len */ + +#ifndef ISA_DMA_THRESHOLD +#define ISA_DMA_THRESHOLD (~0UL) +#endif + +#define ARCH_HAS_SG_CHAIN + +#endif /* __ASM_GENERIC_SCATTERLIST_H */ -- cgit v1.2.3