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git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - include/crypto/scatterwalk.h
2 * Cryptographic scatter and gather helpers.
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 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
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)
16 #ifndef _CRYPTO_SCATTERWALK_H
17 #define _CRYPTO_SCATTERWALK_H
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>
25 #include <linux/scatterlist.h>
26 #include <linux/sched.h>
28 static inline void scatterwalk_crypto_chain(struct scatterlist
*head
,
29 struct scatterlist
*sg
,
33 head
->length
+= sg
->length
;
38 sg_chain(head
, num
, sg
);
43 static inline unsigned long scatterwalk_samebuf(struct scatter_walk
*walk_in
,
44 struct scatter_walk
*walk_out
)
46 return !(((sg_page(walk_in
->sg
) - sg_page(walk_out
->sg
)) << PAGE_SHIFT
) +
47 (int)(walk_in
->offset
- walk_out
->offset
));
50 static inline unsigned int scatterwalk_pagelen(struct scatter_walk
*walk
)
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
;
57 static inline unsigned int scatterwalk_clamp(struct scatter_walk
*walk
,
60 unsigned int len_this_page
= scatterwalk_pagelen(walk
);
61 return nbytes
> len_this_page
? len_this_page
: nbytes
;
64 static inline void scatterwalk_advance(struct scatter_walk
*walk
,
67 walk
->offset
+= nbytes
;
70 static inline unsigned int scatterwalk_aligned(struct scatter_walk
*walk
,
71 unsigned int alignmask
)
73 return !(walk
->offset
& alignmask
);
76 static inline struct page
*scatterwalk_page(struct scatter_walk
*walk
)
78 return sg_page(walk
->sg
) + (walk
->offset
>> PAGE_SHIFT
);
81 static inline void scatterwalk_unmap(void *vaddr
)
86 void scatterwalk_start(struct scatter_walk
*walk
, struct scatterlist
*sg
);
87 void scatterwalk_copychunks(void *buf
, struct scatter_walk
*walk
,
88 size_t nbytes
, int out
);
89 void *scatterwalk_map(struct scatter_walk
*walk
);
90 void scatterwalk_done(struct scatter_walk
*walk
, int out
, int more
);
92 void scatterwalk_map_and_copy(void *buf
, struct scatterlist
*sg
,
93 unsigned int start
, unsigned int nbytes
, int out
);
95 int scatterwalk_bytes_sglen(struct scatterlist
*sg
, int num_bytes
);
97 struct scatterlist
*scatterwalk_ffwd(struct scatterlist dst
[2],
98 struct scatterlist
*src
,
101 #endif /* _CRYPTO_SCATTERWALK_H */