mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
![Robert P. J. Day](/assets/img/avatar_default.png)
To be consistent with other architectures, these two DMA macros should be defined in scatterlist.h as opposed to dma-mapping.h Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
46 lines
1.3 KiB
C
46 lines
1.3 KiB
C
#ifndef _ASM_SCATTERLIST_H
|
|
#define _ASM_SCATTERLIST_H
|
|
|
|
#include <asm/types.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_set_buf(sg, some_ptr, length);
|
|
*
|
|
* and that's it. There's no excuse for not highmem enabling YOUR driver. /jens
|
|
*/
|
|
struct scatterlist {
|
|
#ifdef CONFIG_DEBUG_SG
|
|
unsigned long sg_magic;
|
|
#endif
|
|
unsigned long page_link;
|
|
unsigned int offset; /* for highmem, page offset */
|
|
|
|
dma_addr_t dma_address;
|
|
unsigned int length;
|
|
};
|
|
|
|
/*
|
|
* These macros should be used after a pci_map_sg call has been done
|
|
* to get bus addresses of each of the SG entries and their lengths.
|
|
* You should only work with the number of sg entries pci_map_sg
|
|
* returns, or alternatively stop on the first sg_dma_len(sg) which
|
|
* is 0.
|
|
*/
|
|
#define sg_dma_address(sg) ((sg)->dma_address)
|
|
#define sg_dma_len(sg) ((sg)->length)
|
|
|
|
#define ISA_DMA_THRESHOLD (0xffffffffUL)
|
|
|
|
#endif /* !_ASM_SCATTERLIST_H */
|