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1#ifndef __ASM_GENERIC_SCATTERLIST_H
2#define __ASM_GENERIC_SCATTERLIST_H
3
4#include <linux/types.h>
5
6struct scatterlist {
7#ifdef CONFIG_DEBUG_SG
8 unsigned long sg_magic;
9#endif
10 unsigned long page_link;
11 unsigned int offset;
12 unsigned int length;
13 dma_addr_t dma_address;
14 unsigned int dma_length;
15};
16
17/*
18 * These macros should be used after a dma_map_sg call has been done
19 * to get bus addresses of each of the SG entries and their lengths.
20 * You should only work with the number of sg entries pci_map_sg
21 * returns, or alternatively stop on the first sg_dma_len(sg) which
22 * is 0.
23 */
24#define sg_dma_address(sg) ((sg)->dma_address)
25#ifndef sg_dma_len
26/*
27 * Normally, you have an iommu on 64 bit machines, but not on 32 bit
28 * machines. Architectures that are differnt should override this.
29 */
30#if __BITS_PER_LONG == 64
31#define sg_dma_len(sg) ((sg)->dma_length)
32#else
33#define sg_dma_len(sg) ((sg)->length)
34#endif /* 64 bit */
35#endif /* sg_dma_len */
36
37#ifndef ISA_DMA_THRESHOLD
38#define ISA_DMA_THRESHOLD (~0UL)
39#endif
40
41#define ARCH_HAS_SG_CHAIN
42
43#endif /* __ASM_GENERIC_SCATTERLIST_H */