include/linux/scatterlist.h

58 	struct scatterlist *sg;
79 #define	sg_is_chain(sg)		((sg)->page_link & SG_PAGE_LINK_CHAIN)
80 #define	sg_is_last(sg)		((sg)->page_link & SG_PAGE_LINK_LAST)
81 #define	sg_chain_ptr(sg)	\
82 	((struct scatterlist *) ((sg)->page_link & ~SG_PAGE_LINK_MASK))
84 #define	sg_dma_address(sg)	(sg)->address
85 #define	sg_dma_len(sg)		(sg)->length
89 	     (iter)->sg; _sg_iter_next(iter))
93 #define	for_each_sg(sglist, sg, sgmax, iter)				\
94 	for (iter = 0, sg = (sglist); iter < (sgmax); iter++, sg = sg_next(sg))
100 sg_assign_page(struct scatterlist *sg, struct page *page)
102 	unsigned long page_link = sg->page_link & SG_PAGE_LINK_MASK;
104 	sg->page_link = page_link | (unsigned long)page;
108 sg_set_page(struct scatterlist *sg, struct page *page, unsigned int len,
111 	sg_assign_page(sg, page);
112 	sg->offset = offset;
113 	sg->length = len;
117 sg_page(struct scatterlist *sg)
119 	return ((struct page *)((sg)->page_link & ~SG_PAGE_LINK_MASK));
123 sg_set_buf(struct scatterlist *sg, const void *buf, unsigned int buflen)
125 	sg_set_page(sg, virt_to_page(buf), buflen,
130 sg_next(struct scatterlist *sg)
132 	if (sg_is_last(sg))
134 	sg++;
135 	if (sg_is_chain(sg))
136 		sg = sg_chain_ptr(sg);
137 	return (sg);
141 sg_phys(struct scatterlist *sg)
143 	return (VM_PAGE_TO_PHYS(sg_page(sg)) + sg->offset);
147 sg_virt(struct scatterlist *sg)
150 	return ((void *)((unsigned long)page_address(sg_page(sg)) + sg->offset));
157 	struct scatterlist *sg = &prv[prv_nents - 1];
159 	sg->offset = 0;
160 	sg->length = 0;
161 	sg->page_link = ((unsigned long)sgl |
166 sg_mark_end(struct scatterlist *sg)
168 	sg->page_link |= SG_PAGE_LINK_LAST;
169 	sg->page_link &= ~SG_PAGE_LINK_CHAIN;
173 sg_init_table(struct scatterlist *sg, unsigned int nents)
175 	bzero(sg, sizeof(*sg) * nents);
176 	sg_mark_end(&sg[nents - 1]);
189 sg_kfree(struct scatterlist *sg, unsigned int nents)
192 		free_page((unsigned long)sg);
194 		kfree(sg);
242 	struct scatterlist *sg, *prv;
264 			sg = first_chunk;
267 			sg = alloc_fn(alloc_size, gfp_mask);
269 		if (unlikely(!sg)) {
275 		sg_init_table(sg, alloc_size);
279 			sg_chain(prv, max_ents, sg);
281 			table->sgl = sg;
284 			sg_mark_end(&sg[sg_size - 1]);
286 		prv = sg;
364 sg_nents(struct scatterlist *sg)
368 	for (nents = 0; sg; sg = sg_next(sg))
381 	piter->sg = sglist;
388 	struct scatterlist *sg;
391 	sg = iter->sg;
392 	pgcount = (sg->offset + sg->length + PAGE_SIZE - 1) >> PAGE_SHIFT;
397 		sg = sg_next(sg);
399 		if (sg == NULL || iter->maxents == 0)
401 		pgcount = (sg->offset + sg->length + PAGE_SIZE - 1) >> PAGE_SHIFT;
403 	iter->sg = sg;
407 sg_page_count(struct scatterlist *sg)
409 	return (PAGE_ALIGN(sg->offset + sg->length) >> PAGE_SHIFT);
411 #define	sg_dma_page_count(sg) \
412 	sg_page_count(sg)
421 	if (piter->sg == NULL)
428 		pgcount = sg_page_count(piter->sg);
432 		piter->sg = sg_next(piter->sg);
435 		if (piter->sg == NULL)
448 		iter->sg = sgl;
453 		iter->sg = NULL;
469 	__dma_address = __spi->sg->address +	\
477 	return (nth_page(sg_page(piter->sg), piter->sg_pgoffset));