1234567891011121314151617181920212223242526272829303132 |
- #ifndef _ASM_SCATTERLIST_H
- #define _ASM_SCATTERLIST_H
- /*
- * Drivers must set either ->address or (preferred) ->page and ->offset
- * to indicate where data must be transferred to/from.
- *
- * Using ->page is recommended since it handles highmem data as well as
- * low mem. ->address is restricted to data which has a virtual mapping, and
- * it will go away in the future. Updating to ->page can be automated very
- * easily -- something like
- *
- * sg->address = some_ptr;
- *
- * can be rewritten as
- *
- * sg->page = virt_to_page(some_ptr);
- * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK;
- *
- * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
- */
- struct scatterlist {
- struct page *page; /* Location for highmem page, if any */
- unsigned int offset; /* for highmem, page offset */
- dma_addr_t dma_address;
- unsigned int length;
- };
- #define ISA_DMA_THRESHOLD (0xffffffffUL)
- #endif /* !_ASM_SCATTERLIST_H */
|