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#ifndef _LINUX_SCATTERLIST_H
#define _LINUX_SCATTERLIST_H
#include <linux/string.h>
#include <linux/bug.h>
#include <linux/mm.h>
#include <asm/types.h>
#include <asm/scatterlist.h>
#include <asm/io.h>
struct sg_table {
struct scatterlist *sgl;
unsigned int nents;
unsigned int orig_nents;
};
#define SG_MAGIC 0x87654321
#define sg_is_chain(sg) ((sg)->page_link & 0x01)
#define sg_is_last(sg) ((sg)->page_link & 0x02)
#define sg_chain_ptr(sg) \
((struct scatterlist *) ((sg)->page_link & ~0x03))
static inline void sg_assign_page(struct scatterlist *sg, struct page *page)
{
unsigned long page_link = sg->page_link & 0x3;
BUG_ON((unsigned long) page & 0x03);
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
#endif
sg->page_link = page_link | (unsigned long) page;
}
static inline void sg_set_page(struct scatterlist *sg, struct page *page,
unsigned int len, unsigned int offset)
{
sg_assign_page(sg, page);
sg->offset = offset;
sg->length = len;
}
static inline struct page *sg_page(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
BUG_ON(sg_is_chain(sg));
#endif
return (struct page *)((sg)->page_link & ~0x3);
}
static inline void sg_set_buf(struct scatterlist *sg, const void *buf,
unsigned int buflen)
{
sg_set_page(sg, virt_to_page(buf), buflen, offset_in_page(buf));
}
#define for_each_sg(sglist, sg, nr, __i) \
for (__i = 0, sg = (sglist); __i < (nr); __i++, sg = sg_next(sg))
static inline void sg_chain(struct scatterlist *prv, unsigned int prv_nents,
struct scatterlist *sgl)
{
#ifndef ARCH_HAS_SG_CHAIN
BUG();
#endif
prv[prv_nents - 1].offset = 0;
prv[prv_nents - 1].length = 0;
prv[prv_nents - 1].page_link = ((unsigned long) sgl | 0x01) & ~0x02;
}
static inline void sg_mark_end(struct scatterlist *sg)
{
#ifdef CONFIG_DEBUG_SG
BUG_ON(sg->sg_magic != SG_MAGIC);
#endif
sg->page_link |= 0x02;
sg->page_link &= ~0x01;
}
static inline dma_addr_t sg_phys(struct scatterlist *sg)
{
return page_to_phys(sg_page(sg)) + sg->offset;
}
static inline void *sg_virt(struct scatterlist *sg)
{
return page_address(sg_page(sg)) + sg->offset;
}
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);
typedef struct scatterlist *(sg_alloc_fn)(unsigned int, gfp_t);
typedef void (sg_free_fn)(struct scatterlist *, unsigned int);
void __sg_free_table(struct sg_table *, unsigned int, sg_free_fn *);
void sg_free_table(struct sg_table *);
int __sg_alloc_table(struct sg_table *, unsigned int, unsigned int, gfp_t,
sg_alloc_fn *);
int sg_alloc_table(struct sg_table *, unsigned int, gfp_t);
size_t sg_copy_from_buffer(struct scatterlist *sgl, unsigned int nents,
void *buf, size_t buflen);
size_t sg_copy_to_buffer(struct scatterlist *sgl, unsigned int nents,
void *buf, size_t buflen);
#define SG_MAX_SINGLE_ALLOC (PAGE_SIZE / sizeof(struct scatterlist))
#define SG_MITER_ATOMIC (1 << 0)
#define SG_MITER_TO_SG (1 << 1)
#define SG_MITER_FROM_SG (1 << 2)
struct sg_mapping_iter {
struct page *page;
void *addr;
size_t length;
size_t consumed;
struct scatterlist *__sg;
unsigned int __nents;
unsigned int __offset;
unsigned int __flags;
};
void sg_miter_start(struct sg_mapping_iter *miter, struct scatterlist *sgl,
unsigned int nents, unsigned int flags);
bool sg_miter_next(struct sg_mapping_iter *miter);
void sg_miter_stop(struct sg_mapping_iter *miter);
#endif
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