text: #ifndef _ALPHA_SCATTERLIST_H
  #define _ALPHA_SCATTERLIST_H
  
  #include <linux/types.h>
  
  struct scatterlist {
  	char *address;			/* Source/target vaddr.  */
  	char *alt_address;		/* Location of actual if address is a
  					   dma indirect buffer, else NULL.  */
  	dma_addr_t dma_address;
  	unsigned int length;
  	unsigned int dma_length;
  };
  
  #define sg_dma_address(sg) ((sg)->dma_address)
  #define sg_dma_len(sg)     ((sg)->dma_length)
  
  #define ISA_DMA_THRESHOLD (~0UL)
  
  #endif /* !(_ALPHA_SCATTERLIST_H) */
  