2 * Handle async block request by crypto hardware engine.
4 * Copyright (C) 2016 Linaro, Inc.
6 * Author: Baolin Wang <baolin.wang@linaro.org>
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; either version 2 of the License, or (at your option)
15 #include <linux/err.h>
16 #include <linux/delay.h>
17 #include <crypto/engine.h>
18 #include <crypto/internal/hash.h>
19 #include <uapi/linux/sched/types.h>
22 #define CRYPTO_ENGINE_MAX_QLEN 10
25 * crypto_pump_requests - dequeue one request from engine queue to process
26 * @engine: the hardware engine
27 * @in_kthread: true if we are in the context of the request pump thread
29 * This function checks if there is any request in the engine queue that
30 * needs processing and if so call out to the driver to initialize hardware
31 * and handle each request.
33 static void crypto_pump_requests(struct crypto_engine *engine,
36 struct crypto_async_request *async_req, *backlog;
37 struct ahash_request *hreq;
38 struct ablkcipher_request *breq;
40 bool was_busy = false;
43 spin_lock_irqsave(&engine->queue_lock, flags);
45 /* Make sure we are not already running a request */
49 /* If another context is idling then defer */
51 kthread_queue_work(engine->kworker, &engine->pump_requests);
55 /* Check if the engine queue is idle */
56 if (!crypto_queue_len(&engine->queue) || !engine->running) {
60 /* Only do teardown in the thread */
62 kthread_queue_work(engine->kworker,
63 &engine->pump_requests);
68 engine->idling = true;
69 spin_unlock_irqrestore(&engine->queue_lock, flags);
71 if (engine->unprepare_crypt_hardware &&
72 engine->unprepare_crypt_hardware(engine))
73 pr_err("failed to unprepare crypt hardware\n");
75 spin_lock_irqsave(&engine->queue_lock, flags);
76 engine->idling = false;
80 /* Get the fist request from the engine queue to handle */
81 backlog = crypto_get_backlog(&engine->queue);
82 async_req = crypto_dequeue_request(&engine->queue);
86 engine->cur_req = async_req;
88 backlog->complete(backlog, -EINPROGRESS);
95 spin_unlock_irqrestore(&engine->queue_lock, flags);
97 rtype = crypto_tfm_alg_type(engine->cur_req->tfm);
98 /* Until here we get the request need to be encrypted successfully */
99 if (!was_busy && engine->prepare_crypt_hardware) {
100 ret = engine->prepare_crypt_hardware(engine);
102 pr_err("failed to prepare crypt hardware\n");
108 case CRYPTO_ALG_TYPE_AHASH:
109 hreq = ahash_request_cast(engine->cur_req);
110 if (engine->prepare_hash_request) {
111 ret = engine->prepare_hash_request(engine, hreq);
113 pr_err("failed to prepare request: %d\n", ret);
116 engine->cur_req_prepared = true;
118 ret = engine->hash_one_request(engine, hreq);
120 pr_err("failed to hash one request from queue\n");
124 case CRYPTO_ALG_TYPE_ABLKCIPHER:
125 breq = ablkcipher_request_cast(engine->cur_req);
126 if (engine->prepare_cipher_request) {
127 ret = engine->prepare_cipher_request(engine, breq);
129 pr_err("failed to prepare request: %d\n", ret);
132 engine->cur_req_prepared = true;
134 ret = engine->cipher_one_request(engine, breq);
136 pr_err("failed to cipher one request from queue\n");
141 pr_err("failed to prepare request of unknown type\n");
147 case CRYPTO_ALG_TYPE_AHASH:
148 hreq = ahash_request_cast(engine->cur_req);
149 crypto_finalize_hash_request(engine, hreq, ret);
151 case CRYPTO_ALG_TYPE_ABLKCIPHER:
152 breq = ablkcipher_request_cast(engine->cur_req);
153 crypto_finalize_cipher_request(engine, breq, ret);
159 spin_unlock_irqrestore(&engine->queue_lock, flags);
162 static void crypto_pump_work(struct kthread_work *work)
164 struct crypto_engine *engine =
165 container_of(work, struct crypto_engine, pump_requests);
167 crypto_pump_requests(engine, true);
171 * crypto_transfer_cipher_request - transfer the new request into the
173 * @engine: the hardware engine
174 * @req: the request need to be listed into the engine queue
176 int crypto_transfer_cipher_request(struct crypto_engine *engine,
177 struct ablkcipher_request *req,
183 spin_lock_irqsave(&engine->queue_lock, flags);
185 if (!engine->running) {
186 spin_unlock_irqrestore(&engine->queue_lock, flags);
190 ret = ablkcipher_enqueue_request(&engine->queue, req);
192 if (!engine->busy && need_pump)
193 kthread_queue_work(engine->kworker, &engine->pump_requests);
195 spin_unlock_irqrestore(&engine->queue_lock, flags);
198 EXPORT_SYMBOL_GPL(crypto_transfer_cipher_request);
201 * crypto_transfer_cipher_request_to_engine - transfer one request to list
202 * into the engine queue
203 * @engine: the hardware engine
204 * @req: the request need to be listed into the engine queue
206 int crypto_transfer_cipher_request_to_engine(struct crypto_engine *engine,
207 struct ablkcipher_request *req)
209 return crypto_transfer_cipher_request(engine, req, true);
211 EXPORT_SYMBOL_GPL(crypto_transfer_cipher_request_to_engine);
214 * crypto_transfer_hash_request - transfer the new request into the
216 * @engine: the hardware engine
217 * @req: the request need to be listed into the engine queue
219 int crypto_transfer_hash_request(struct crypto_engine *engine,
220 struct ahash_request *req, bool need_pump)
225 spin_lock_irqsave(&engine->queue_lock, flags);
227 if (!engine->running) {
228 spin_unlock_irqrestore(&engine->queue_lock, flags);
232 ret = ahash_enqueue_request(&engine->queue, req);
234 if (!engine->busy && need_pump)
235 kthread_queue_work(engine->kworker, &engine->pump_requests);
237 spin_unlock_irqrestore(&engine->queue_lock, flags);
240 EXPORT_SYMBOL_GPL(crypto_transfer_hash_request);
243 * crypto_transfer_hash_request_to_engine - transfer one request to list
244 * into the engine queue
245 * @engine: the hardware engine
246 * @req: the request need to be listed into the engine queue
248 int crypto_transfer_hash_request_to_engine(struct crypto_engine *engine,
249 struct ahash_request *req)
251 return crypto_transfer_hash_request(engine, req, true);
253 EXPORT_SYMBOL_GPL(crypto_transfer_hash_request_to_engine);
256 * crypto_finalize_cipher_request - finalize one request if the request is done
257 * @engine: the hardware engine
258 * @req: the request need to be finalized
261 void crypto_finalize_cipher_request(struct crypto_engine *engine,
262 struct ablkcipher_request *req, int err)
265 bool finalize_cur_req = false;
268 spin_lock_irqsave(&engine->queue_lock, flags);
269 if (engine->cur_req == &req->base)
270 finalize_cur_req = true;
271 spin_unlock_irqrestore(&engine->queue_lock, flags);
273 if (finalize_cur_req) {
274 if (engine->cur_req_prepared &&
275 engine->unprepare_cipher_request) {
276 ret = engine->unprepare_cipher_request(engine, req);
278 pr_err("failed to unprepare request\n");
280 spin_lock_irqsave(&engine->queue_lock, flags);
281 engine->cur_req = NULL;
282 engine->cur_req_prepared = false;
283 spin_unlock_irqrestore(&engine->queue_lock, flags);
286 req->base.complete(&req->base, err);
288 kthread_queue_work(engine->kworker, &engine->pump_requests);
290 EXPORT_SYMBOL_GPL(crypto_finalize_cipher_request);
293 * crypto_finalize_hash_request - finalize one request if the request is done
294 * @engine: the hardware engine
295 * @req: the request need to be finalized
298 void crypto_finalize_hash_request(struct crypto_engine *engine,
299 struct ahash_request *req, int err)
302 bool finalize_cur_req = false;
305 spin_lock_irqsave(&engine->queue_lock, flags);
306 if (engine->cur_req == &req->base)
307 finalize_cur_req = true;
308 spin_unlock_irqrestore(&engine->queue_lock, flags);
310 if (finalize_cur_req) {
311 if (engine->cur_req_prepared &&
312 engine->unprepare_hash_request) {
313 ret = engine->unprepare_hash_request(engine, req);
315 pr_err("failed to unprepare request\n");
317 spin_lock_irqsave(&engine->queue_lock, flags);
318 engine->cur_req = NULL;
319 engine->cur_req_prepared = false;
320 spin_unlock_irqrestore(&engine->queue_lock, flags);
323 req->base.complete(&req->base, err);
325 kthread_queue_work(engine->kworker, &engine->pump_requests);
327 EXPORT_SYMBOL_GPL(crypto_finalize_hash_request);
330 * crypto_engine_start - start the hardware engine
331 * @engine: the hardware engine need to be started
333 * Return 0 on success, else on fail.
335 int crypto_engine_start(struct crypto_engine *engine)
339 spin_lock_irqsave(&engine->queue_lock, flags);
341 if (engine->running || engine->busy) {
342 spin_unlock_irqrestore(&engine->queue_lock, flags);
346 engine->running = true;
347 spin_unlock_irqrestore(&engine->queue_lock, flags);
349 kthread_queue_work(engine->kworker, &engine->pump_requests);
353 EXPORT_SYMBOL_GPL(crypto_engine_start);
356 * crypto_engine_stop - stop the hardware engine
357 * @engine: the hardware engine need to be stopped
359 * Return 0 on success, else on fail.
361 int crypto_engine_stop(struct crypto_engine *engine)
364 unsigned int limit = 500;
367 spin_lock_irqsave(&engine->queue_lock, flags);
370 * If the engine queue is not empty or the engine is on busy state,
371 * we need to wait for a while to pump the requests of engine queue.
373 while ((crypto_queue_len(&engine->queue) || engine->busy) && limit--) {
374 spin_unlock_irqrestore(&engine->queue_lock, flags);
376 spin_lock_irqsave(&engine->queue_lock, flags);
379 if (crypto_queue_len(&engine->queue) || engine->busy)
382 engine->running = false;
384 spin_unlock_irqrestore(&engine->queue_lock, flags);
387 pr_warn("could not stop engine\n");
391 EXPORT_SYMBOL_GPL(crypto_engine_stop);
394 * crypto_engine_alloc_init - allocate crypto hardware engine structure and
396 * @dev: the device attached with one hardware engine
397 * @rt: whether this queue is set to run as a realtime task
399 * This must be called from context that can sleep.
400 * Return: the crypto engine structure on success, else NULL.
402 struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
404 struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
405 struct crypto_engine *engine;
410 engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL);
415 engine->running = false;
416 engine->busy = false;
417 engine->idling = false;
418 engine->cur_req_prepared = false;
419 engine->priv_data = dev;
420 snprintf(engine->name, sizeof(engine->name),
421 "%s-engine", dev_name(dev));
423 crypto_init_queue(&engine->queue, CRYPTO_ENGINE_MAX_QLEN);
424 spin_lock_init(&engine->queue_lock);
426 engine->kworker = kthread_create_worker(0, "%s", engine->name);
427 if (IS_ERR(engine->kworker)) {
428 dev_err(dev, "failed to create crypto request pump task\n");
431 kthread_init_work(&engine->pump_requests, crypto_pump_work);
434 dev_info(dev, "will run requests pump with realtime priority\n");
435 sched_setscheduler(engine->kworker->task, SCHED_FIFO, ¶m);
440 EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
443 * crypto_engine_exit - free the resources of hardware engine when exit
444 * @engine: the hardware engine need to be freed
446 * Return 0 for success.
448 int crypto_engine_exit(struct crypto_engine *engine)
452 ret = crypto_engine_stop(engine);
456 kthread_destroy_worker(engine->kworker);
460 EXPORT_SYMBOL_GPL(crypto_engine_exit);
462 MODULE_LICENSE("GPL");
463 MODULE_DESCRIPTION("Crypto hardware engine framework");