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 enum km_type crypto_kmap_type(int out) |
29 | { | |
30 | enum km_type type; | |
31 | ||
32 | if (in_softirq()) | |
33 | type = out * (KM_SOFTIRQ1 - KM_SOFTIRQ0) + KM_SOFTIRQ0; | |
34 | else | |
35 | type = out * (KM_USER1 - KM_USER0) + KM_USER0; | |
36 | ||
37 | return type; | |
38 | } | |
39 | ||
40 | static inline void *crypto_kmap(struct page *page, int out) | |
41 | { | |
42 | return kmap_atomic(page, crypto_kmap_type(out)); | |
43 | } | |
44 | ||
45 | static inline void crypto_kunmap(void *vaddr, int out) | |
46 | { | |
47 | kunmap_atomic(vaddr, crypto_kmap_type(out)); | |
48 | } | |
49 | ||
50 | static inline void crypto_yield(u32 flags) | |
51 | { | |
52 | if (flags & CRYPTO_TFM_REQ_MAY_SLEEP) | |
53 | cond_resched(); | |
54 | } | |
1da177e4 | 55 | |
b2ab4a57 HX |
56 | static inline void scatterwalk_sg_chain(struct scatterlist *sg1, int num, |
57 | struct scatterlist *sg2) | |
58 | { | |
59 | sg_set_page(&sg1[num - 1], (void *)sg2, 0, 0); | |
8ec970d8 | 60 | sg1[num - 1].page_link &= ~0x02; |
b2ab4a57 HX |
61 | } |
62 | ||
63 | static inline struct scatterlist *scatterwalk_sg_next(struct scatterlist *sg) | |
64 | { | |
8ec970d8 HX |
65 | if (sg_is_last(sg)) |
66 | return NULL; | |
67 | ||
b2ab4a57 HX |
68 | return (++sg)->length ? sg : (void *)sg_page(sg); |
69 | } | |
70 | ||
079f2f74 SK |
71 | static inline void scatterwalk_crypto_chain(struct scatterlist *head, |
72 | struct scatterlist *sg, | |
73 | int chain, int num) | |
74 | { | |
75 | if (chain) { | |
76 | head->length += sg->length; | |
77 | sg = scatterwalk_sg_next(sg); | |
78 | } | |
79 | ||
80 | if (sg) | |
81 | scatterwalk_sg_chain(head, num, sg); | |
82 | else | |
83 | sg_mark_end(head); | |
84 | } | |
85 | ||
5c64097a HX |
86 | static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in, |
87 | struct scatter_walk *walk_out) | |
1da177e4 | 88 | { |
78c2f0b8 | 89 | return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) + |
5c64097a HX |
90 | (int)(walk_in->offset - walk_out->offset)); |
91 | } | |
92 | ||
93 | static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk) | |
94 | { | |
95 | unsigned int len = walk->sg->offset + walk->sg->length - walk->offset; | |
96 | unsigned int len_this_page = offset_in_page(~walk->offset) + 1; | |
97 | return len_this_page > len ? len : len_this_page; | |
1da177e4 LT |
98 | } |
99 | ||
c774e93e HX |
100 | static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk, |
101 | unsigned int nbytes) | |
1da177e4 | 102 | { |
5c64097a HX |
103 | unsigned int len_this_page = scatterwalk_pagelen(walk); |
104 | return nbytes > len_this_page ? len_this_page : nbytes; | |
1da177e4 LT |
105 | } |
106 | ||
107 | static inline void scatterwalk_advance(struct scatter_walk *walk, | |
108 | unsigned int nbytes) | |
109 | { | |
1da177e4 | 110 | walk->offset += nbytes; |
1da177e4 LT |
111 | } |
112 | ||
95477377 HX |
113 | static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk, |
114 | unsigned int alignmask) | |
115 | { | |
116 | return !(walk->offset & alignmask); | |
117 | } | |
118 | ||
5c64097a HX |
119 | static inline struct page *scatterwalk_page(struct scatter_walk *walk) |
120 | { | |
78c2f0b8 | 121 | return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); |
5c64097a HX |
122 | } |
123 | ||
124 | static inline void scatterwalk_unmap(void *vaddr, int out) | |
125 | { | |
126 | crypto_kunmap(vaddr, out); | |
127 | } | |
128 | ||
1da177e4 | 129 | void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg); |
5c64097a HX |
130 | void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, |
131 | size_t nbytes, int out); | |
132 | void *scatterwalk_map(struct scatter_walk *walk, int out); | |
1da177e4 LT |
133 | void scatterwalk_done(struct scatter_walk *walk, int out, int more); |
134 | ||
5fa0fea2 HX |
135 | void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg, |
136 | unsigned int start, unsigned int nbytes, int out); | |
137 | ||
1da177e4 | 138 | #endif /* _CRYPTO_SCATTERWALK_H */ |