1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * Asynchronous Compression operations
  4 *
  5 * Copyright (c) 2016, Intel Corporation
  6 * Authors: Weigang Li <weigang.li@intel.com>
  7 *          Giovanni Cabiddu <giovanni.cabiddu@intel.com>
  8 */
  9#ifndef _CRYPTO_ACOMP_H
 10#define _CRYPTO_ACOMP_H
 11#include <linux/crypto.h>
 12
 13#define CRYPTO_ACOMP_ALLOC_OUTPUT	0x00000001
 14
 15/**
 16 * struct acomp_req - asynchronous (de)compression request
 17 *
 18 * @base:	Common attributes for asynchronous crypto requests
 19 * @src:	Source Data
 20 * @dst:	Destination data
 21 * @slen:	Size of the input buffer
 22 * @dlen:	Size of the output buffer and number of bytes produced
 23 * @flags:	Internal flags
 24 * @__ctx:	Start of private context data
 25 */
 26struct acomp_req {
 27	struct crypto_async_request base;
 28	struct scatterlist *src;
 29	struct scatterlist *dst;
 30	unsigned int slen;
 31	unsigned int dlen;
 32	u32 flags;
 33	void *__ctx[] CRYPTO_MINALIGN_ATTR;
 34};
 35
 36/**
 37 * struct crypto_acomp - user-instantiated objects which encapsulate
 38 * algorithms and core processing logic
 39 *
 40 * @compress:		Function performs a compress operation
 41 * @decompress:		Function performs a de-compress operation
 42 * @dst_free:		Frees destination buffer if allocated inside the
 43 *			algorithm
 44 * @reqsize:		Context size for (de)compression requests
 45 * @base:		Common crypto API algorithm data structure
 46 */
 47struct crypto_acomp {
 48	int (*compress)(struct acomp_req *req);
 49	int (*decompress)(struct acomp_req *req);
 50	void (*dst_free)(struct scatterlist *dst);
 51	unsigned int reqsize;
 52	struct crypto_tfm base;
 53};
 54
 55/**
 56 * struct acomp_alg - asynchronous compression algorithm
 57 *
 58 * @compress:	Function performs a compress operation
 59 * @decompress:	Function performs a de-compress operation
 60 * @dst_free:	Frees destination buffer if allocated inside the algorithm
 61 * @init:	Initialize the cryptographic transformation object.
 62 *		This function is used to initialize the cryptographic
 63 *		transformation object. This function is called only once at
 64 *		the instantiation time, right after the transformation context
 65 *		was allocated. In case the cryptographic hardware has some
 66 *		special requirements which need to be handled by software, this
 67 *		function shall check for the precise requirement of the
 68 *		transformation and put any software fallbacks in place.
 69 * @exit:	Deinitialize the cryptographic transformation object. This is a
 70 *		counterpart to @init, used to remove various changes set in
 71 *		@init.
 72 *
 73 * @reqsize:	Context size for (de)compression requests
 74 * @base:	Common crypto API algorithm data structure
 75 */
 76struct acomp_alg {
 77	int (*compress)(struct acomp_req *req);
 78	int (*decompress)(struct acomp_req *req);
 79	void (*dst_free)(struct scatterlist *dst);
 80	int (*init)(struct crypto_acomp *tfm);
 81	void (*exit)(struct crypto_acomp *tfm);
 82	unsigned int reqsize;
 83	struct crypto_alg base;
 84};
 85
 86/**
 87 * DOC: Asynchronous Compression API
 88 *
 89 * The Asynchronous Compression API is used with the algorithms of type
 90 * CRYPTO_ALG_TYPE_ACOMPRESS (listed as type "acomp" in /proc/crypto)
 91 */
 92
 93/**
 94 * crypto_alloc_acomp() -- allocate ACOMPRESS tfm handle
 95 * @alg_name:	is the cra_name / name or cra_driver_name / driver name of the
 96 *		compression algorithm e.g. "deflate"
 97 * @type:	specifies the type of the algorithm
 98 * @mask:	specifies the mask for the algorithm
 99 *
100 * Allocate a handle for a compression algorithm. The returned struct
101 * crypto_acomp is the handle that is required for any subsequent
102 * API invocation for the compression operations.
103 *
104 * Return:	allocated handle in case of success; IS_ERR() is true in case
105 *		of an error, PTR_ERR() returns the error code.
106 */
107struct crypto_acomp *crypto_alloc_acomp(const char *alg_name, u32 type,
108					u32 mask);
109
110static inline struct crypto_tfm *crypto_acomp_tfm(struct crypto_acomp *tfm)
111{
112	return &tfm->base;
113}
114
115static inline struct acomp_alg *__crypto_acomp_alg(struct crypto_alg *alg)
116{
117	return container_of(alg, struct acomp_alg, base);
118}
119
120static inline struct crypto_acomp *__crypto_acomp_tfm(struct crypto_tfm *tfm)
121{
122	return container_of(tfm, struct crypto_acomp, base);
123}
124
125static inline struct acomp_alg *crypto_acomp_alg(struct crypto_acomp *tfm)
126{
127	return __crypto_acomp_alg(crypto_acomp_tfm(tfm)->__crt_alg);
128}
129
130static inline unsigned int crypto_acomp_reqsize(struct crypto_acomp *tfm)
131{
132	return tfm->reqsize;
133}
134
135static inline void acomp_request_set_tfm(struct acomp_req *req,
136					 struct crypto_acomp *tfm)
137{
138	req->base.tfm = crypto_acomp_tfm(tfm);
139}
140
141static inline struct crypto_acomp *crypto_acomp_reqtfm(struct acomp_req *req)
142{
143	return __crypto_acomp_tfm(req->base.tfm);
144}
145
146/**
147 * crypto_free_acomp() -- free ACOMPRESS tfm handle
148 *
149 * @tfm:	ACOMPRESS tfm handle allocated with crypto_alloc_acomp()
150 */
151static inline void crypto_free_acomp(struct crypto_acomp *tfm)
152{
153	crypto_destroy_tfm(tfm, crypto_acomp_tfm(tfm));
154}
155
156static inline int crypto_has_acomp(const char *alg_name, u32 type, u32 mask)
157{
158	type &= ~CRYPTO_ALG_TYPE_MASK;
159	type |= CRYPTO_ALG_TYPE_ACOMPRESS;
160	mask |= CRYPTO_ALG_TYPE_MASK;
161
162	return crypto_has_alg(alg_name, type, mask);
163}
164
165/**
166 * acomp_request_alloc() -- allocates asynchronous (de)compression request
167 *
168 * @tfm:	ACOMPRESS tfm handle allocated with crypto_alloc_acomp()
169 *
170 * Return:	allocated handle in case of success or NULL in case of an error
171 */
172struct acomp_req *acomp_request_alloc(struct crypto_acomp *tfm);
173
174/**
175 * acomp_request_free() -- zeroize and free asynchronous (de)compression
176 *			   request as well as the output buffer if allocated
177 *			   inside the algorithm
178 *
179 * @req:	request to free
180 */
181void acomp_request_free(struct acomp_req *req);
182
183/**
184 * acomp_request_set_callback() -- Sets an asynchronous callback
185 *
186 * Callback will be called when an asynchronous operation on a given
187 * request is finished.
188 *
189 * @req:	request that the callback will be set for
190 * @flgs:	specify for instance if the operation may backlog
191 * @cmlp:	callback which will be called
192 * @data:	private data used by the caller
193 */
194static inline void acomp_request_set_callback(struct acomp_req *req,
195					      u32 flgs,
196					      crypto_completion_t cmpl,
197					      void *data)
198{
199	req->base.complete = cmpl;
200	req->base.data = data;
201	req->base.flags = flgs;
202}
203
204/**
205 * acomp_request_set_params() -- Sets request parameters
206 *
207 * Sets parameters required by an acomp operation
208 *
209 * @req:	asynchronous compress request
210 * @src:	pointer to input buffer scatterlist
211 * @dst:	pointer to output buffer scatterlist. If this is NULL, the
212 *		acomp layer will allocate the output memory
213 * @slen:	size of the input buffer
214 * @dlen:	size of the output buffer. If dst is NULL, this can be used by
215 *		the user to specify the maximum amount of memory to allocate
216 */
217static inline void acomp_request_set_params(struct acomp_req *req,
218					    struct scatterlist *src,
219					    struct scatterlist *dst,
220					    unsigned int slen,
221					    unsigned int dlen)
222{
223	req->src = src;
224	req->dst = dst;
225	req->slen = slen;
226	req->dlen = dlen;
227
228	if (!req->dst)
229		req->flags |= CRYPTO_ACOMP_ALLOC_OUTPUT;
230}
231
232/**
233 * crypto_acomp_compress() -- Invoke asynchronous compress operation
234 *
235 * Function invokes the asynchronous compress operation
236 *
237 * @req:	asynchronous compress request
238 *
239 * Return:	zero on success; error code in case of error
240 */
241static inline int crypto_acomp_compress(struct acomp_req *req)
242{
243	struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
244	struct crypto_alg *alg = tfm->base.__crt_alg;
245	unsigned int slen = req->slen;
246	int ret;
247
248	crypto_stats_get(alg);
249	ret = tfm->compress(req);
250	crypto_stats_compress(slen, ret, alg);
251	return ret;
252}
253
254/**
255 * crypto_acomp_decompress() -- Invoke asynchronous decompress operation
256 *
257 * Function invokes the asynchronous decompress operation
258 *
259 * @req:	asynchronous compress request
260 *
261 * Return:	zero on success; error code in case of error
262 */
263static inline int crypto_acomp_decompress(struct acomp_req *req)
264{
265	struct crypto_acomp *tfm = crypto_acomp_reqtfm(req);
266	struct crypto_alg *alg = tfm->base.__crt_alg;
267	unsigned int slen = req->slen;
268	int ret;
269
270	crypto_stats_get(alg);
271	ret = tfm->decompress(req);
272	crypto_stats_decompress(slen, ret, alg);
273	return ret;
274}
275
276#endif