Commit | Line | Data |
---|---|---|
2874c5fd | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
1da177e4 | 2 | /* |
42c271c6 | 3 | * Cryptographic scatter and gather helpers. |
1da177e4 LT |
4 | * |
5 | * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> | |
6 | * Copyright (c) 2002 Adam J. Richter <adam@yggdrasil.com> | |
7 | * Copyright (c) 2004 Jean-Luc Cooke <jlcooke@certainkey.com> | |
42c271c6 | 8 | * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au> |
1da177e4 LT |
9 | */ |
10 | ||
11 | #ifndef _CRYPTO_SCATTERWALK_H | |
12 | #define _CRYPTO_SCATTERWALK_H | |
5c64097a | 13 | |
42c271c6 | 14 | #include <crypto/algapi.h> |
244d22ff | 15 | |
42c271c6 | 16 | #include <linux/highmem.h> |
244d22ff | 17 | #include <linux/mm.h> |
5c64097a | 18 | #include <linux/scatterlist.h> |
1da177e4 | 19 | |
079f2f74 | 20 | static inline void scatterwalk_crypto_chain(struct scatterlist *head, |
8c30fbe6 | 21 | struct scatterlist *sg, int num) |
079f2f74 | 22 | { |
079f2f74 | 23 | if (sg) |
c56f6d12 | 24 | sg_chain(head, num, sg); |
079f2f74 SK |
25 | else |
26 | sg_mark_end(head); | |
27 | } | |
28 | ||
5c64097a HX |
29 | static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk) |
30 | { | |
31 | unsigned int len = walk->sg->offset + walk->sg->length - walk->offset; | |
32 | unsigned int len_this_page = offset_in_page(~walk->offset) + 1; | |
33 | return len_this_page > len ? len : len_this_page; | |
1da177e4 LT |
34 | } |
35 | ||
c774e93e HX |
36 | static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk, |
37 | unsigned int nbytes) | |
1da177e4 | 38 | { |
5c64097a HX |
39 | unsigned int len_this_page = scatterwalk_pagelen(walk); |
40 | return nbytes > len_this_page ? len_this_page : nbytes; | |
1da177e4 LT |
41 | } |
42 | ||
43 | static inline void scatterwalk_advance(struct scatter_walk *walk, | |
44 | unsigned int nbytes) | |
45 | { | |
1da177e4 | 46 | walk->offset += nbytes; |
1da177e4 LT |
47 | } |
48 | ||
5c64097a HX |
49 | static inline struct page *scatterwalk_page(struct scatter_walk *walk) |
50 | { | |
78c2f0b8 | 51 | return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT); |
5c64097a HX |
52 | } |
53 | ||
f0dfc0b0 | 54 | static inline void scatterwalk_unmap(void *vaddr) |
5c64097a | 55 | { |
aa969515 | 56 | kunmap_local(vaddr); |
5c64097a HX |
57 | } |
58 | ||
ac027258 HX |
59 | static inline void scatterwalk_start(struct scatter_walk *walk, |
60 | struct scatterlist *sg) | |
61 | { | |
62 | walk->sg = sg; | |
63 | walk->offset = sg->offset; | |
64 | } | |
65 | ||
66 | static inline void *scatterwalk_map(struct scatter_walk *walk) | |
67 | { | |
aa969515 | 68 | return kmap_local_page(scatterwalk_page(walk)) + |
ac027258 HX |
69 | offset_in_page(walk->offset); |
70 | } | |
71 | ||
72 | static inline void scatterwalk_pagedone(struct scatter_walk *walk, int out, | |
73 | unsigned int more) | |
74 | { | |
75 | if (out) { | |
76 | struct page *page; | |
77 | ||
78 | page = sg_page(walk->sg) + ((walk->offset - 1) >> PAGE_SHIFT); | |
b0d2193b | 79 | flush_dcache_page(page); |
ac027258 HX |
80 | } |
81 | ||
82 | if (more && walk->offset >= walk->sg->offset + walk->sg->length) | |
83 | scatterwalk_start(walk, sg_next(walk->sg)); | |
84 | } | |
85 | ||
86 | static inline void scatterwalk_done(struct scatter_walk *walk, int out, | |
87 | int more) | |
88 | { | |
89 | if (!more || walk->offset >= walk->sg->offset + walk->sg->length || | |
90 | !(walk->offset & (PAGE_SIZE - 1))) | |
91 | scatterwalk_pagedone(walk, out, more); | |
92 | } | |
93 | ||
5c64097a HX |
94 | void scatterwalk_copychunks(void *buf, struct scatter_walk *walk, |
95 | size_t nbytes, int out); | |
1da177e4 | 96 | |
5fa0fea2 HX |
97 | void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg, |
98 | unsigned int start, unsigned int nbytes, int out); | |
99 | ||
fc42bcba HX |
100 | struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2], |
101 | struct scatterlist *src, | |
102 | unsigned int len); | |
103 | ||
1da177e4 | 104 | #endif /* _CRYPTO_SCATTERWALK_H */ |