diff options
Diffstat (limited to 'kernel/include/linux/scatterlist.h')
| -rw-r--r-- | kernel/include/linux/scatterlist.h | 56 |
1 files changed, 43 insertions, 13 deletions
diff --git a/kernel/include/linux/scatterlist.h b/kernel/include/linux/scatterlist.h index ed8f9e70d..556ec1ea2 100644 --- a/kernel/include/linux/scatterlist.h +++ b/kernel/include/linux/scatterlist.h @@ -2,13 +2,39 @@ #define _LINUX_SCATTERLIST_H #include <linux/string.h> +#include <linux/types.h> #include <linux/bug.h> #include <linux/mm.h> - -#include <asm/types.h> -#include <asm/scatterlist.h> #include <asm/io.h> +struct scatterlist { +#ifdef CONFIG_DEBUG_SG + unsigned long sg_magic; +#endif + unsigned long page_link; + unsigned int offset; + unsigned int length; + dma_addr_t dma_address; +#ifdef CONFIG_NEED_SG_DMA_LENGTH + unsigned int dma_length; +#endif +}; + +/* + * These macros should be used after a dma_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 dma_map_sg + * returns, or alternatively stop on the first sg_dma_len(sg) which + * is 0. + */ +#define sg_dma_address(sg) ((sg)->dma_address) + +#ifdef CONFIG_NEED_SG_DMA_LENGTH +#define sg_dma_len(sg) ((sg)->dma_length) +#else +#define sg_dma_len(sg) ((sg)->length) +#endif + struct sg_table { struct scatterlist *sgl; /* the list */ unsigned int nents; /* number of mapped entries */ @@ -18,10 +44,9 @@ struct sg_table { /* * Notes on SG table design. * - * Architectures must provide an unsigned long page_link field in the - * scatterlist struct. We use that to place the page pointer AND encode - * information about the sg table as well. The two lower bits are reserved - * for this information. + * We use the unsigned long page_link field in the scatterlist struct to place + * the page pointer AND encode information about the sg table as well. The two + * lower bits are reserved for this information. * * If bit 0 is set, then the page_link contains a pointer to the next sg * table list. Otherwise the next entry is at sg + 1. @@ -136,10 +161,6 @@ static inline void sg_set_buf(struct scatterlist *sg, const void *buf, static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents, struct scatterlist *sgl) { -#ifndef CONFIG_ARCH_HAS_SG_CHAIN - BUG(); -#endif - /* * offset and length are unused for chain entry. Clear them. */ @@ -221,10 +242,16 @@ static inline void *sg_virt(struct scatterlist *sg) } int sg_nents(struct scatterlist *sg); +int sg_nents_for_len(struct scatterlist *sg, u64 len); struct scatterlist *sg_next(struct scatterlist *); struct scatterlist *sg_last(struct scatterlist *s, unsigned int); void sg_init_table(struct scatterlist *, unsigned int); void sg_init_one(struct scatterlist *, const void *, unsigned int); +int sg_split(struct scatterlist *in, const int in_mapped_nents, + const off_t skip, const int nb_splits, + const size_t *split_sizes, + struct scatterlist **out, int *out_mapped_nents, + gfp_t gfp_mask); typedef struct scatterlist *(sg_alloc_fn)(unsigned int, gfp_t); typedef void (sg_free_fn)(struct scatterlist *, unsigned int); @@ -239,13 +266,16 @@ int sg_alloc_table_from_pages(struct sg_table *sgt, unsigned long offset, unsigned long size, gfp_t gfp_mask); +size_t sg_copy_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, + size_t buflen, off_t skip, bool to_buffer); + size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen); + const void *buf, size_t buflen); size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen); size_t sg_pcopy_from_buffer(struct scatterlist *sgl, unsigned int nents, - void *buf, size_t buflen, off_t skip); + const void *buf, size_t buflen, off_t skip); size_t sg_pcopy_to_buffer(struct scatterlist *sgl, unsigned int nents, void *buf, size_t buflen, off_t skip); |