linux/include/asm-m32r/scatterlist.h
Jens Axboe 18dabf473e Change table chaining layout
Change the page member of the scatterlist structure to be an unsigned
long, and encode more stuff in the lower bits:

- Bits 0 and 1 zero: this is a normal sg entry. Next sg entry is located
  at sg + 1.
- Bit 0 set: this is a chain entry, the next real entry is at ->page_link
  with the two low bits masked off.
- Bit 1 set: this is the final entry in the sg entry. sg_next() will return
  NULL when passed such an entry.

It's thus important that sg table users use the proper accessors to get
and set the page member.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-10-22 21:20:01 +02:00

19 lines
447 B
C

#ifndef _ASM_M32R_SCATTERLIST_H
#define _ASM_M32R_SCATTERLIST_H
#include <asm/types.h>
struct scatterlist {
char * address; /* Location data is to be transferred to, NULL for
* highmem page */
unsigned long page_link;
unsigned int offset;/* for highmem, page offset */
dma_addr_t dma_address;
unsigned int length;
};
#define ISA_DMA_THRESHOLD (0x1fffffff)
#endif /* _ASM_M32R_SCATTERLIST_H */