1 /*
2 * Cryptographic API.
3 *
4 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
5 * Copyright (c) 2002 Adam J. Richter <adam@yggdrasil.com>
6 * Copyright (c) 2004 Jean-Luc Cooke <jlcooke@certainkey.com>
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
11 * any later version.
12 *
13 */
14
15 #ifndef _CRYPTO_SCATTERWALK_H
16 #define _CRYPTO_SCATTERWALK_H
17 #include <linux/mm.h>
18 #include <asm/scatterlist.h>
19
20 struct scatter_walk {
21 struct scatterlist *sg;
22 struct page *page;
23 void *data;
24 unsigned int len_this_page;
25 unsigned int len_this_segment;
26 unsigned int offset;
27 };
28
29 /* Define sg_next is an inline routine now in case we want to change
30 scatterlist to a linked list later. */
sg_next(struct scatterlist * sg)31 static inline struct scatterlist *sg_next(struct scatterlist *sg)
32 {
33 return sg + 1;
34 }
35
scatterwalk_samebuf(struct scatter_walk * walk_in,struct scatter_walk * walk_out,void * src_p,void * dst_p)36 static inline int scatterwalk_samebuf(struct scatter_walk *walk_in,
37 struct scatter_walk *walk_out,
38 void *src_p, void *dst_p)
39 {
40 return walk_in->page == walk_out->page &&
41 walk_in->offset == walk_out->offset &&
42 walk_in->data == src_p && walk_out->data == dst_p;
43 }
44
45 void *scatterwalk_whichbuf(struct scatter_walk *walk, unsigned int nbytes, void *scratch);
46 void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg);
47 int scatterwalk_copychunks(void *buf, struct scatter_walk *walk, size_t nbytes, int out);
48 void scatterwalk_map(struct scatter_walk *walk, int out);
49 void scatterwalk_done(struct scatter_walk *walk, int out, int more);
50
51 #endif /* _CRYPTO_SCATTERWALK_H */
52