+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);
+
+/*
+ * Maximum number of entries that will be allocated in one piece, if
+ * a list larger than this is required then chaining will be utilized.
+ */
+#define SG_MAX_SINGLE_ALLOC (PAGE_SIZE / sizeof(struct scatterlist))
+