Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
42c271c6 | 2 | * Cryptographic scatter and gather helpers. |
1da177e4 LT |
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> | |
42c271c6 | 7 | * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au> |
1da177e4 LT |
8 | * |
9 | * This program is free software; you can redistribute it and/or modify it | |
10 | * under the terms of the GNU General Public License as published by the Free | |
11 | * Software Foundation; either version 2 of the License, or (at your option) | |
12 | * any later version. | |
13 | * | |
14 | */ | |
15 | ||
16 | #ifndef _CRYPTO_SCATTERWALK_H | |
17 | #define _CRYPTO_SCATTERWALK_H | |
5c64097a | 18 | |
42c271c6 HX |
19 | #include <asm/kmap_types.h> |
20 | #include <crypto/algapi.h> | |
21 | #include <linux/hardirq.h> | |
22 | #include <linux/highmem.h> | |
23 | #include <linux/kernel.h> | |
1da177e4 | 24 | #include <linux/mm.h> |
5c64097a | 25 | #include <linux/scatterlist.h> |
1c5dfe6a | 26 | #include <linux/sched.h> |
1da177e4 | 27 | |
079f2f74 SK |
28 | static inline void scatterwalk_crypto_chain(struct scatterlist *head, |
29 | struct scatterlist *sg, | |
30 | int chain, int num) | |
31 | { | |
32 | if (chain) { | |
33 | head->length += sg->length; | |
5be4d4c9 | 34 | sg = sg_next(sg); |
079f2f74 SK |
35 | } |
36 | ||
37 | if (sg) | |
c56f6d12 | 38 | sg_chain(head, num, sg); |
079f2f74 SK |
39 | else |
40 | sg_mark_end(head); | |
41 | } | |
42 | ||
5c64097a HX |
43 | static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in, |
44 | struct scatter_walk *walk_out) | |
1da177e4 | 45 | { |
78c2f0b8 | 46 | return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) + |
5c64097a HX |
47 | (int)(walk_in->offset - walk_out->offset)); |
48 | } | |
49 | ||
50 | static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk) | |
51 | { | |
52 | unsigned int len = walk->sg->offset + walk->sg->length - walk->offset; | |
53 | unsigned int len_this_page = offset_in_page(~walk->offset) + 1; | |
54 | return len_this_page > len ? len : len_this_page; | |
1da177e4 LT |
55 | } |
56 | ||
c774e93e HX |
57 | static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk, |
58 | unsigned int nbytes) | |
1da177e4 | 59 | { |
5c64097a HX |
60 | unsigned int len_this_page = scatterwalk_pagelen(walk); |
61 | return nbytes > len_this_page ? len_this_page : nbytes; | |
1da177e4 LT |
62 | } |
63 | ||
64 | static inline void scatterwalk_advance(struct scatter_walk *walk, | |
65 | unsigned int nbytes) | |
66 | { | |
1da177e4 | 67 | walk->offset += nbytes; |
1da177e4 LT |
68 | } |
69 | ||
95477377 HX |
70 | static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk, |
71 | unsigned int alignmask) | |
72 | { | |
73 | return !(walk->offset & alignmask); | |
74 | } | |
75 | ||
5c64097a HX |
76 | static inline struct page *scatterwalk_page(struct scatter_walk *walk) |
77 | { | |
78c2f0b8 | 78 | return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); |
5c64097a HX |
79 | } |
80 | ||
f0dfc0b0 | 81 | static inline void scatterwalk_unmap(void *vaddr) |
5c64097a | 82 | { |
f0dfc0b0 | 83 | kunmap_atomic(vaddr); |
5c64097a HX |
84 | } |
85 | ||
1da177e4 | 86 | void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg); |
5c64097a HX |
87 | void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, |
88 | size_t nbytes, int out); | |
f0dfc0b0 | 89 | void *scatterwalk_map(struct scatter_walk *walk); |
1da177e4 LT |
90 | void scatterwalk_done(struct scatter_walk *walk, int out, int more); |
91 | ||
5fa0fea2 HX |
92 | void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg, |
93 | unsigned int start, unsigned int nbytes, int out); | |
94 | ||
257aff51 JF |
95 | int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes); |
96 | ||
fc42bcba HX |
97 | struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2], |
98 | struct scatterlist *src, | |
99 | unsigned int len); | |
100 | ||
1da177e4 | 101 | #endif /* _CRYPTO_SCATTERWALK_H */ |