[mirror_ubuntu-artful-kernel.git] / include / crypto / scatterwalk.h

/*
 * Cryptographic scatter and gather helpers.
 *
 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
 * Copyright (c) 2002 Adam J. Richter <adam@yggdrasil.com>
 * Copyright (c) 2004 Jean-Luc Cooke <jlcooke@certainkey.com>
 * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#ifndef _CRYPTO_SCATTERWALK_H
#define _CRYPTO_SCATTERWALK_H

#include <asm/kmap_types.h>
#include <crypto/algapi.h>
#include <linux/hardirq.h>
#include <linux/highmem.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/scatterlist.h>
#include <linux/sched.h>

static inline void scatterwalk_sg_chain(struct scatterlist *sg1, int num,
					struct scatterlist *sg2)
{
	sg_set_page(&sg1[num - 1], (void *)sg2, 0, 0);
	sg1[num - 1].page_link &= ~0x02;
	sg1[num - 1].page_link |= 0x01;
}

static inline void scatterwalk_crypto_chain(struct scatterlist *head,
					    struct scatterlist *sg,
					    int chain, int num)
{
	if (chain) {
		head->length += sg->length;
		sg = sg_next(sg);
	}

	if (sg)
		scatterwalk_sg_chain(head, num, sg);
	else
		sg_mark_end(head);
}

static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in,
						struct scatter_walk *walk_out)
{
	return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) +
		 (int)(walk_in->offset - walk_out->offset));
}

static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk)
{
	unsigned int len = walk->sg->offset + walk->sg->length - walk->offset;
	unsigned int len_this_page = offset_in_page(~walk->offset) + 1;
	return len_this_page > len ? len : len_this_page;
}

static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk,
					     unsigned int nbytes)
{
	unsigned int len_this_page = scatterwalk_pagelen(walk);
	return nbytes > len_this_page ? len_this_page : nbytes;
}

static inline void scatterwalk_advance(struct scatter_walk *walk,
				       unsigned int nbytes)
{
	walk->offset += nbytes;
}

static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk,
					       unsigned int alignmask)
{
	return !(walk->offset & alignmask);
}

static inline struct page *scatterwalk_page(struct scatter_walk *walk)
{
	return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
}

static inline void scatterwalk_unmap(void *vaddr)
{
	kunmap_atomic(vaddr);
}

void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg);
void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
			    size_t nbytes, int out);
void *scatterwalk_map(struct scatter_walk *walk);
void scatterwalk_done(struct scatter_walk *walk, int out, int more);

void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
			      unsigned int start, unsigned int nbytes, int out);

int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes);

struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
				     struct scatterlist *src,
				     unsigned int len);

#endif  /* _CRYPTO_SCATTERWALK_H */
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
b2ab4a57 HX	28	static inline void scatterwalk_sg_chain(struct scatterlist *sg1, int num,
	29	struct scatterlist *sg2)
	30	{
	31	sg_set_page(&sg1[num - 1], (void *)sg2, 0, 0);
8ec970d8	32	sg1[num - 1].page_link &= ~0x02;
41da8b5a	33	sg1[num - 1].page_link \|= 0x01;
b2ab4a57 HX	34	}
b2ab4a57 HX	35
079f2f74 SK	36	static inline void scatterwalk_crypto_chain(struct scatterlist *head,
	37	struct scatterlist *sg,
	38	int chain, int num)
	39	{
	40	if (chain) {
	41	head->length += sg->length;
5be4d4c9	42	sg = sg_next(sg);
079f2f74 SK	43	}
	44
	45	if (sg)
	46	scatterwalk_sg_chain(head, num, sg);
	47	else
	48	sg_mark_end(head);
	49	}
	50
5c64097a HX	51	static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in,
5c64097a HX	52	struct scatter_walk *walk_out)
1da177e4	53	{
78c2f0b8	54	return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) +
5c64097a HX	55	(int)(walk_in->offset - walk_out->offset));
	56	}
	57
	58	static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk)
	59	{
	60	unsigned int len = walk->sg->offset + walk->sg->length - walk->offset;
	61	unsigned int len_this_page = offset_in_page(~walk->offset) + 1;
	62	return len_this_page > len ? len : len_this_page;
1da177e4 LT	63	}
1da177e4 LT	64
c774e93e HX	65	static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk,
c774e93e HX	66	unsigned int nbytes)
1da177e4	67	{
5c64097a HX	68	unsigned int len_this_page = scatterwalk_pagelen(walk);
5c64097a HX	69	return nbytes > len_this_page ? len_this_page : nbytes;
1da177e4 LT	70	}
	71
	72	static inline void scatterwalk_advance(struct scatter_walk *walk,
	73	unsigned int nbytes)
	74	{
1da177e4	75	walk->offset += nbytes;
1da177e4 LT	76	}
1da177e4 LT	77
95477377 HX	78	static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk,
	79	unsigned int alignmask)
	80	{
	81	return !(walk->offset & alignmask);
	82	}
	83
5c64097a HX	84	static inline struct page scatterwalk_page(struct scatter_walk walk)
5c64097a HX	85	{
78c2f0b8	86	return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
5c64097a HX	87	}
5c64097a HX	88
f0dfc0b0	89	static inline void scatterwalk_unmap(void *vaddr)
5c64097a	90	{
f0dfc0b0	91	kunmap_atomic(vaddr);
5c64097a HX	92	}
5c64097a HX	93
1da177e4	94	void scatterwalk_start(struct scatter_walk walk, struct scatterlist sg);
5c64097a HX	95	void scatterwalk_copychunks(void buf, struct scatter_walk walk,
5c64097a HX	96	size_t nbytes, int out);
f0dfc0b0	97	void scatterwalk_map(struct scatter_walk walk);
1da177e4 LT	98	void scatterwalk_done(struct scatter_walk *walk, int out, int more);
1da177e4 LT	99
5fa0fea2 HX	100	void scatterwalk_map_and_copy(void buf, struct scatterlist sg,
	101	unsigned int start, unsigned int nbytes, int out);
	102
257aff51 JF	103	int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes);
257aff51 JF	104
fc42bcba HX	105	struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
	106	struct scatterlist *src,
	107	unsigned int len);
	108
1da177e4	109	#endif /* _CRYPTO_SCATTERWALK_H */