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 | |
42c271c6 HX |
28 | static inline void crypto_yield(u32 flags) |
29 | { | |
30 | if (flags & CRYPTO_TFM_REQ_MAY_SLEEP) | |
31 | cond_resched(); | |
32 | } | |
1da177e4 | 33 | |
b2ab4a57 HX |
34 | static inline void scatterwalk_sg_chain(struct scatterlist *sg1, int num, |
35 | struct scatterlist *sg2) | |
36 | { | |
37 | sg_set_page(&sg1[num - 1], (void *)sg2, 0, 0); | |
8ec970d8 | 38 | sg1[num - 1].page_link &= ~0x02; |
b2ab4a57 HX |
39 | } |
40 | ||
41 | static inline struct scatterlist *scatterwalk_sg_next(struct scatterlist *sg) | |
42 | { | |
8ec970d8 HX |
43 | if (sg_is_last(sg)) |
44 | return NULL; | |
45 | ||
b2ab4a57 HX |
46 | return (++sg)->length ? sg : (void *)sg_page(sg); |
47 | } | |
48 | ||
079f2f74 SK |
49 | static inline void scatterwalk_crypto_chain(struct scatterlist *head, |
50 | struct scatterlist *sg, | |
51 | int chain, int num) | |
52 | { | |
53 | if (chain) { | |
54 | head->length += sg->length; | |
55 | sg = scatterwalk_sg_next(sg); | |
56 | } | |
57 | ||
58 | if (sg) | |
59 | scatterwalk_sg_chain(head, num, sg); | |
60 | else | |
61 | sg_mark_end(head); | |
62 | } | |
63 | ||
5c64097a HX |
64 | static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in, |
65 | struct scatter_walk *walk_out) | |
1da177e4 | 66 | { |
78c2f0b8 | 67 | return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) + |
5c64097a HX |
68 | (int)(walk_in->offset - walk_out->offset)); |
69 | } | |
70 | ||
71 | static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk) | |
72 | { | |
73 | unsigned int len = walk->sg->offset + walk->sg->length - walk->offset; | |
74 | unsigned int len_this_page = offset_in_page(~walk->offset) + 1; | |
75 | return len_this_page > len ? len : len_this_page; | |
1da177e4 LT |
76 | } |
77 | ||
c774e93e HX |
78 | static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk, |
79 | unsigned int nbytes) | |
1da177e4 | 80 | { |
5c64097a HX |
81 | unsigned int len_this_page = scatterwalk_pagelen(walk); |
82 | return nbytes > len_this_page ? len_this_page : nbytes; | |
1da177e4 LT |
83 | } |
84 | ||
85 | static inline void scatterwalk_advance(struct scatter_walk *walk, | |
86 | unsigned int nbytes) | |
87 | { | |
1da177e4 | 88 | walk->offset += nbytes; |
1da177e4 LT |
89 | } |
90 | ||
95477377 HX |
91 | static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk, |
92 | unsigned int alignmask) | |
93 | { | |
94 | return !(walk->offset & alignmask); | |
95 | } | |
96 | ||
5c64097a HX |
97 | static inline struct page *scatterwalk_page(struct scatter_walk *walk) |
98 | { | |
78c2f0b8 | 99 | return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); |
5c64097a HX |
100 | } |
101 | ||
f0dfc0b0 | 102 | static inline void scatterwalk_unmap(void *vaddr) |
5c64097a | 103 | { |
f0dfc0b0 | 104 | kunmap_atomic(vaddr); |
5c64097a HX |
105 | } |
106 | ||
1da177e4 | 107 | void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg); |
5c64097a HX |
108 | void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, |
109 | size_t nbytes, int out); | |
f0dfc0b0 | 110 | void *scatterwalk_map(struct scatter_walk *walk); |
1da177e4 LT |
111 | void scatterwalk_done(struct scatter_walk *walk, int out, int more); |
112 | ||
5fa0fea2 HX |
113 | void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg, |
114 | unsigned int start, unsigned int nbytes, int out); | |
115 | ||
257aff51 JF |
116 | int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes); |
117 | ||
1da177e4 | 118 | #endif /* _CRYPTO_SCATTERWALK_H */ |