112 lines
2.9 KiB
C
112 lines
2.9 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
||
|
|
/*
|
||
|
|
* 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>
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef _CRYPTO_SCATTERWALK_H
|
||
|
|
#define _CRYPTO_SCATTERWALK_H
|
||
|
|
|
||
|
|
#include <crypto/algapi.h>
|
||
|
|
|
||
|
|
#include <linux/highmem.h>
|
||
|
|
#include <linux/mm.h>
|
||
|
|
#include <linux/scatterlist.h>
|
||
|
|
|
||
|
|
static inline void scatterwalk_crypto_chain(struct scatterlist *head,
|
||
|
|
struct scatterlist *sg, int num)
|
||
|
|
{
|
||
|
|
if (sg)
|
||
|
|
sg_chain(head, num, sg);
|
||
|
|
else
|
||
|
|
sg_mark_end(head);
|
||
|
|
}
|
||
|
|
|
||
|
|
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);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void scatterwalk_start(struct scatter_walk *walk,
|
||
|
|
struct scatterlist *sg)
|
||
|
|
{
|
||
|
|
walk->sg = sg;
|
||
|
|
walk->offset = sg->offset;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void *scatterwalk_map(struct scatter_walk *walk)
|
||
|
|
{
|
||
|
|
return kmap_atomic(scatterwalk_page(walk)) +
|
||
|
|
offset_in_page(walk->offset);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void scatterwalk_pagedone(struct scatter_walk *walk, int out,
|
||
|
|
unsigned int more)
|
||
|
|
{
|
||
|
|
if (out) {
|
||
|
|
struct page *page;
|
||
|
|
|
||
|
|
page = sg_page(walk->sg) + ((walk->offset - 1) >> PAGE_SHIFT);
|
||
|
|
flush_dcache_page(page);
|
||
|
|
}
|
||
|
|
|
||
|
|
if (more && walk->offset >= walk->sg->offset + walk->sg->length)
|
||
|
|
scatterwalk_start(walk, sg_next(walk->sg));
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline void scatterwalk_done(struct scatter_walk *walk, int out,
|
||
|
|
int more)
|
||
|
|
{
|
||
|
|
if (!more || walk->offset >= walk->sg->offset + walk->sg->length ||
|
||
|
|
!(walk->offset & (PAGE_SIZE - 1)))
|
||
|
|
scatterwalk_pagedone(walk, out, more);
|
||
|
|
}
|
||
|
|
|
||
|
|
void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
|
||
|
|
size_t nbytes, int out);
|
||
|
|
void *scatterwalk_map(struct scatter_walk *walk);
|
||
|
|
|
||
|
|
void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
|
||
|
|
unsigned int start, unsigned int nbytes, int out);
|
||
|
|
|
||
|
|
struct scatterlist *scatterwalk_ffwd(struct scatterlist dst[2],
|
||
|
|
struct scatterlist *src,
|
||
|
|
unsigned int len);
|
||
|
|
|
||
|
|
#endif /* _CRYPTO_SCATTERWALK_H */
|