linux/include/crypto/acompress.h
Giovanni Cabiddu 1ab53a77b7 crypto: acomp - add driver-side scomp interface
Add a synchronous back-end (scomp) to acomp. This allows to easily
expose the already present compression algorithms in LKCF via acomp.

Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-10-25 11:08:31 +08:00

270 lines
7.8 KiB
C

/*
* Asynchronous Compression operations
*
* Copyright (c) 2016, Intel Corporation
* Authors: Weigang Li <weigang.li@intel.com>
* Giovanni Cabiddu <giovanni.cabiddu@intel.com>
*
* 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_ACOMP_H
#define _CRYPTO_ACOMP_H
#include <linux/crypto.h>
#define CRYPTO_ACOMP_ALLOC_OUTPUT 0x00000001
/**
* struct acomp_req - asynchronous (de)compression request
*
* @base: Common attributes for asynchronous crypto requests
* @src: Source Data
* @dst: Destination data
* @slen: Size of the input buffer
* @dlen: Size of the output buffer and number of bytes produced
* @flags: Internal flags
* @__ctx: Start of private context data
*/
struct acomp_req {
struct crypto_async_request base;
struct scatterlist *src;
struct scatterlist *dst;
unsigned int slen;
unsigned int dlen;
u32 flags;
void *__ctx[] CRYPTO_MINALIGN_ATTR;
};
/**
* struct crypto_acomp - user-instantiated objects which encapsulate
* algorithms and core processing logic
*
* @compress: Function performs a compress operation
* @decompress: Function performs a de-compress operation
* @dst_free: Frees destination buffer if allocated inside the
* algorithm
* @reqsize: Context size for (de)compression requests
* @base: Common crypto API algorithm data structure
*/
struct crypto_acomp {
int (*compress)(struct acomp_req *req);
int (*decompress)(struct acomp_req *req);
void (*dst_free)(struct scatterlist *dst);
unsigned int reqsize;
struct crypto_tfm base;
};
/**
* struct acomp_alg - asynchronous compression algorithm
*
* @compress: Function performs a compress operation
* @decompress: Function performs a de-compress operation
* @dst_free: Frees destination buffer if allocated inside the algorithm
* @init: Initialize the cryptographic transformation object.
* This function is used to initialize the cryptographic
* transformation object. This function is called only once at
* the instantiation time, right after the transformation context
* was allocated. In case the cryptographic hardware has some
* special requirements which need to be handled by software, this
* function shall check for the precise requirement of the
* transformation and put any software fallbacks in place.
* @exit: Deinitialize the cryptographic transformation object. This is a
* counterpart to @init, used to remove various changes set in
* @init.
*
* @reqsize: Context size for (de)compression requests
* @base: Common crypto API algorithm data structure
*/
struct acomp_alg {
int (*compress)(struct acomp_req *req);
int (*decompress)(struct acomp_req *req);
void (*dst_free)(struct scatterlist *dst);
int (*init)(struct crypto_acomp *tfm);
void (*exit)(struct crypto_acomp *tfm);
unsigned int reqsize;
struct crypto_alg base;
};
/**
* DOC: Asynchronous Compression API
*
* The Asynchronous Compression API is used with the algorithms of type
* CRYPTO_ALG_TYPE_ACOMPRESS (listed as type "acomp" in /proc/crypto)
*/
/**
* crypto_alloc_acomp() -- allocate ACOMPRESS tfm handle
* @alg_name: is the cra_name / name or cra_driver_name / driver name of the
* compression algorithm e.g. "deflate"
* @type: specifies the type of the algorithm
* @mask: specifies the mask for the algorithm
*
* Allocate a handle for a compression algorithm. The returned struct
* crypto_acomp is the handle that is required for any subsequent
* API invocation for the compression operations.
*
* Return: allocated handle in case of success; IS_ERR() is true in case
* of an error, PTR_ERR() returns the error code.
*/
struct crypto_acomp *crypto_alloc_acomp(const char *alg_name, u32 type,
u32 mask);
static inline struct crypto_tfm *crypto_acomp_tfm(struct crypto_acomp *tfm)
{
return &tfm->base;
}
static inline struct acomp_alg *__crypto_acomp_alg(struct crypto_alg *alg)
{
return container_of(alg, struct acomp_alg, base);
}
static inline struct crypto_acomp *__crypto_acomp_tfm(struct crypto_tfm *tfm)
{
return container_of(tfm, struct crypto_acomp, base);
}
static inline struct acomp_alg *crypto_acomp_alg(struct crypto_acomp *tfm)
{
return __crypto_acomp_alg(crypto_acomp_tfm(tfm)->__crt_alg);
}
static inline unsigned int crypto_acomp_reqsize(struct crypto_acomp *tfm)
{
return tfm->reqsize;
}
static inline void acomp_request_set_tfm(struct acomp_req *req,
struct crypto_acomp *tfm)
{
req->base.tfm = crypto_acomp_tfm(tfm);
}
static inline struct crypto_acomp *crypto_acomp_reqtfm(struct acomp_req *req)
{
return __crypto_acomp_tfm(req->base.tfm);
}
/**
* crypto_free_acomp() -- free ACOMPRESS tfm handle
*
* @tfm: ACOMPRESS tfm handle allocated with crypto_alloc_acomp()
*/
static inline void crypto_free_acomp(struct crypto_acomp *tfm)
{
crypto_destroy_tfm(tfm, crypto_acomp_tfm(tfm));
}
static inline int crypto_has_acomp(const char *alg_name, u32 type, u32 mask)
{
type &= ~CRYPTO_ALG_TYPE_MASK;
type |= CRYPTO_ALG_TYPE_ACOMPRESS;
mask |= CRYPTO_ALG_TYPE_MASK;
return crypto_has_alg(alg_name, type, mask);
}
/**
* acomp_request_alloc() -- allocates asynchronous (de)compression request
*
* @tfm: ACOMPRESS tfm handle allocated with crypto_alloc_acomp()
*
* Return: allocated handle in case of success or NULL in case of an error
*/
struct acomp_req *acomp_request_alloc(struct crypto_acomp *tfm);
/**
* acomp_request_free() -- zeroize and free asynchronous (de)compression
* request as well as the output buffer if allocated
* inside the algorithm
*
* @req: request to free
*/
void acomp_request_free(struct acomp_req *req);
/**
* acomp_request_set_callback() -- Sets an asynchronous callback
*
* Callback will be called when an asynchronous operation on a given
* request is finished.
*
* @req: request that the callback will be set for
* @flgs: specify for instance if the operation may backlog
* @cmlp: callback which will be called
* @data: private data used by the caller
*/
static inline void acomp_request_set_callback(struct acomp_req *req,
u32 flgs,
crypto_completion_t cmpl,
void *data)
{
req->base.complete = cmpl;
req->base.data = data;
req->base.flags = flgs;
}
/**
* acomp_request_set_params() -- Sets request parameters
*
* Sets parameters required by an acomp operation
*
* @req: asynchronous compress request
* @src: pointer to input buffer scatterlist
* @dst: pointer to output buffer scatterlist. If this is NULL, the
* acomp layer will allocate the output memory
* @slen: size of the input buffer
* @dlen: size of the output buffer. If dst is NULL, this can be used by
* the user to specify the maximum amount of memory to allocate
*/
static inline void acomp_request_set_params(struct acomp_req *req,
struct scatterlist *src,
struct scatterlist *dst,
unsigned int slen,
unsigned int dlen)
{
req->src = src;
req->dst = dst;
req->slen = slen;
req->dlen = dlen;
if (!req->dst)
req->flags |= CRYPTO_ACOMP_ALLOC_OUTPUT;
}
/**
* crypto_acomp_compress() -- Invoke asynchronous compress operation
*
* Function invokes the asynchronous compress operation
*
* @req: asynchronous compress request
*
* Return: zero on success; error code in case of error
*/
static inline int crypto_acomp_compress(struct acomp_req *req)
{
struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
return tfm->compress(req);
}
/**
* crypto_acomp_decompress() -- Invoke asynchronous decompress operation
*
* Function invokes the asynchronous decompress operation
*
* @req: asynchronous compress request
*
* Return: zero on success; error code in case of error
*/
static inline int crypto_acomp_decompress(struct acomp_req *req)
{
struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
return tfm->decompress(req);
}
#endif