scatterlist.h 924 B

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  1. #ifndef _ASM_SCATTERLIST_H
  2. #define _ASM_SCATTERLIST_H
  3. #include <asm/types.h>
  4. /*
  5. * Drivers must set either ->address or (preferred) page and ->offset
  6. * to indicate where data must be transferred to/from.
  7. *
  8. * Using page is recommended since it handles highmem data as well as
  9. * low mem. ->address is restricted to data which has a virtual mapping, and
  10. * it will go away in the future. Updating to page can be automated very
  11. * easily -- something like
  12. *
  13. * sg->address = some_ptr;
  14. *
  15. * can be rewritten as
  16. *
  17. * sg_set_buf(sg, some_ptr, length);
  18. *
  19. * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
  20. */
  21. struct scatterlist {
  22. #ifdef CONFIG_DEBUG_SG
  23. unsigned long sg_magic;
  24. #endif
  25. unsigned long page_link;
  26. unsigned int offset; /* for highmem, page offset */
  27. dma_addr_t dma_address;
  28. unsigned int length;
  29. };
  30. #define ISA_DMA_THRESHOLD (0xffffffffUL)
  31. #endif /* !_ASM_SCATTERLIST_H */