include/asm-generic/scatterlist.h

   1 #ifndef __ASM_GENERIC_SCATTERLIST_H
   2 #define __ASM_GENERIC_SCATTERLIST_H
   3
   4 #include <linux/types.h>
   5
   6 struct 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 #ifdef CONFIG_NEED_SG_DMA_LENGTH
  15         unsigned int    dma_length;
  16 #endif
  17 };
  18
  19 /*
  20  * These macros should be used after a dma_map_sg call has been done
  21  * to get bus addresses of each of the SG entries and their lengths.
  22  * You should only work with the number of sg entries pci_map_sg
  23  * returns, or alternatively stop on the first sg_dma_len(sg) which
  24  * is 0.
  25  */
  26 #define sg_dma_address(sg)      ((sg)->dma_address)
  27
  28 #ifdef CONFIG_NEED_SG_DMA_LENGTH
  29 #define sg_dma_len(sg)          ((sg)->dma_length)
  30 #else
  31 #define sg_dma_len(sg)          ((sg)->length)
  32 #endif
  33
  34 #endif /* __ASM_GENERIC_SCATTERLIST_H */