| David Howells | b920de1 | 2008-02-08 04:19:31 -0800 | [diff] [blame] | 1 | /* MN10300 Scatterlist definitions | 
 | 2 |  * | 
 | 3 |  * Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd. | 
 | 4 |  * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | 
 | 5 |  * | 
 | 6 |  * This program is free software; you can redistribute it and/or | 
 | 7 |  * modify it under the terms of the GNU General Public Licence | 
 | 8 |  * as published by the Free Software Foundation; either version | 
 | 9 |  * 2 of the Licence, or (at your option) any later version. | 
 | 10 |  */ | 
 | 11 | #ifndef _ASM_SCATTERLIST_H | 
 | 12 | #define _ASM_SCATTERLIST_H | 
 | 13 |  | 
 | 14 | #include <asm/types.h> | 
 | 15 |  | 
 | 16 | /* | 
 | 17 |  * Drivers must set either ->address or (preferred) page and ->offset | 
 | 18 |  * to indicate where data must be transferred to/from. | 
 | 19 |  * | 
 | 20 |  * Using page is recommended since it handles highmem data as well as | 
 | 21 |  * low mem. ->address is restricted to data which has a virtual mapping, and | 
 | 22 |  * it will go away in the future. Updating to page can be automated very | 
 | 23 |  * easily -- something like | 
 | 24 |  * | 
 | 25 |  * sg->address = some_ptr; | 
 | 26 |  * | 
 | 27 |  * can be rewritten as | 
 | 28 |  * | 
 | 29 |  * sg_set_page(virt_to_page(some_ptr)); | 
 | 30 |  * sg->offset = (unsigned long) some_ptr & ~PAGE_MASK; | 
 | 31 |  * | 
 | 32 |  * and that's it. There's no excuse for not highmem enabling YOUR driver. /jens | 
 | 33 |  */ | 
 | 34 | struct scatterlist { | 
 | 35 | #ifdef CONFIG_DEBUG_SG | 
 | 36 | 	unsigned long	sg_magic; | 
 | 37 | #endif | 
 | 38 | 	unsigned long	page_link; | 
 | 39 | 	unsigned int	offset;		/* for highmem, page offset */ | 
 | 40 | 	dma_addr_t	dma_address; | 
 | 41 | 	unsigned int	length; | 
 | 42 | }; | 
 | 43 |  | 
 | 44 | #define ISA_DMA_THRESHOLD (0x00ffffff) | 
 | 45 |  | 
 | 46 | #endif /* _ASM_SCATTERLIST_H */ |