1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Handle async block request by crypto hardware engine.
5 * Copyright (C) 2016 Linaro, Inc.
7 * Author: Baolin Wang <baolin.wang@linaro.org>
10 #include <linux/err.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <crypto/engine.h>
14 #include <uapi/linux/sched/types.h>
17 #define CRYPTO_ENGINE_MAX_QLEN 10
20 * crypto_finalize_request - finalize one request if the request is done
21 * @engine: the hardware engine
22 * @req: the request need to be finalized
25 static void crypto_finalize_request(struct crypto_engine *engine,
26 struct crypto_async_request *req, int err)
29 bool finalize_req = false;
31 struct crypto_engine_ctx *enginectx;
34 * If hardware cannot enqueue more requests
35 * and retry mechanism is not supported
36 * make sure we are completing the current request
38 if (!engine->retry_support) {
39 spin_lock_irqsave(&engine->queue_lock, flags);
40 if (engine->cur_req == req) {
42 engine->cur_req = NULL;
44 spin_unlock_irqrestore(&engine->queue_lock, flags);
47 if (finalize_req || engine->retry_support) {
48 enginectx = crypto_tfm_ctx(req->tfm);
49 if (enginectx->op.prepare_request &&
50 enginectx->op.unprepare_request) {
51 ret = enginectx->op.unprepare_request(engine, req);
53 dev_err(engine->dev, "failed to unprepare request\n");
56 lockdep_assert_in_softirq();
57 crypto_request_complete(req, err);
59 kthread_queue_work(engine->kworker, &engine->pump_requests);
63 * crypto_pump_requests - dequeue one request from engine queue to process
64 * @engine: the hardware engine
65 * @in_kthread: true if we are in the context of the request pump thread
67 * This function checks if there is any request in the engine queue that
68 * needs processing and if so call out to the driver to initialize hardware
69 * and handle each request.
71 static void crypto_pump_requests(struct crypto_engine *engine,
74 struct crypto_async_request *async_req, *backlog;
76 bool was_busy = false;
78 struct crypto_engine_ctx *enginectx;
80 spin_lock_irqsave(&engine->queue_lock, flags);
82 /* Make sure we are not already running a request */
83 if (!engine->retry_support && engine->cur_req)
86 /* If another context is idling then defer */
88 kthread_queue_work(engine->kworker, &engine->pump_requests);
92 /* Check if the engine queue is idle */
93 if (!crypto_queue_len(&engine->queue) || !engine->running) {
97 /* Only do teardown in the thread */
99 kthread_queue_work(engine->kworker,
100 &engine->pump_requests);
104 engine->busy = false;
105 engine->idling = true;
106 spin_unlock_irqrestore(&engine->queue_lock, flags);
108 if (engine->unprepare_crypt_hardware &&
109 engine->unprepare_crypt_hardware(engine))
110 dev_err(engine->dev, "failed to unprepare crypt hardware\n");
112 spin_lock_irqsave(&engine->queue_lock, flags);
113 engine->idling = false;
118 /* Get the fist request from the engine queue to handle */
119 backlog = crypto_get_backlog(&engine->queue);
120 async_req = crypto_dequeue_request(&engine->queue);
125 * If hardware doesn't support the retry mechanism,
126 * keep track of the request we are processing now.
127 * We'll need it on completion (crypto_finalize_request).
129 if (!engine->retry_support)
130 engine->cur_req = async_req;
137 spin_unlock_irqrestore(&engine->queue_lock, flags);
139 /* Until here we get the request need to be encrypted successfully */
140 if (!was_busy && engine->prepare_crypt_hardware) {
141 ret = engine->prepare_crypt_hardware(engine);
143 dev_err(engine->dev, "failed to prepare crypt hardware\n");
148 enginectx = crypto_tfm_ctx(async_req->tfm);
150 if (enginectx->op.prepare_request) {
151 ret = enginectx->op.prepare_request(engine, async_req);
153 dev_err(engine->dev, "failed to prepare request: %d\n",
158 if (!enginectx->op.do_one_request) {
159 dev_err(engine->dev, "failed to do request\n");
164 ret = enginectx->op.do_one_request(engine, async_req);
166 /* Request unsuccessfully executed by hardware */
169 * If hardware queue is full (-ENOSPC), requeue request
170 * regardless of backlog flag.
171 * Otherwise, unprepare and complete the request.
173 if (!engine->retry_support ||
176 "Failed to do one request from queue: %d\n",
181 * If retry mechanism is supported,
182 * unprepare current request and
183 * enqueue it back into crypto-engine queue.
185 if (enginectx->op.unprepare_request) {
186 ret = enginectx->op.unprepare_request(engine,
190 "failed to unprepare request\n");
192 spin_lock_irqsave(&engine->queue_lock, flags);
194 * If hardware was unable to execute request, enqueue it
195 * back in front of crypto-engine queue, to keep the order
198 crypto_enqueue_request_head(&engine->queue, async_req);
200 kthread_queue_work(engine->kworker, &engine->pump_requests);
207 if (enginectx->op.unprepare_request) {
208 ret = enginectx->op.unprepare_request(engine, async_req);
210 dev_err(engine->dev, "failed to unprepare request\n");
214 crypto_request_complete(async_req, ret);
218 crypto_request_complete(backlog, -EINPROGRESS);
220 /* If retry mechanism is supported, send new requests to engine */
221 if (engine->retry_support) {
222 spin_lock_irqsave(&engine->queue_lock, flags);
228 spin_unlock_irqrestore(&engine->queue_lock, flags);
231 * Batch requests is possible only if
232 * hardware can enqueue multiple requests
234 if (engine->do_batch_requests) {
235 ret = engine->do_batch_requests(engine);
237 dev_err(engine->dev, "failed to do batch requests: %d\n",
244 static void crypto_pump_work(struct kthread_work *work)
246 struct crypto_engine *engine =
247 container_of(work, struct crypto_engine, pump_requests);
249 crypto_pump_requests(engine, true);
253 * crypto_transfer_request - transfer the new request into the engine queue
254 * @engine: the hardware engine
255 * @req: the request need to be listed into the engine queue
257 static int crypto_transfer_request(struct crypto_engine *engine,
258 struct crypto_async_request *req,
264 spin_lock_irqsave(&engine->queue_lock, flags);
266 if (!engine->running) {
267 spin_unlock_irqrestore(&engine->queue_lock, flags);
271 ret = crypto_enqueue_request(&engine->queue, req);
273 if (!engine->busy && need_pump)
274 kthread_queue_work(engine->kworker, &engine->pump_requests);
276 spin_unlock_irqrestore(&engine->queue_lock, flags);
281 * crypto_transfer_request_to_engine - transfer one request to list
282 * into the engine queue
283 * @engine: the hardware engine
284 * @req: the request need to be listed into the engine queue
286 static int crypto_transfer_request_to_engine(struct crypto_engine *engine,
287 struct crypto_async_request *req)
289 return crypto_transfer_request(engine, req, true);
293 * crypto_transfer_aead_request_to_engine - transfer one aead_request
294 * to list into the engine queue
295 * @engine: the hardware engine
296 * @req: the request need to be listed into the engine queue
298 int crypto_transfer_aead_request_to_engine(struct crypto_engine *engine,
299 struct aead_request *req)
301 return crypto_transfer_request_to_engine(engine, &req->base);
303 EXPORT_SYMBOL_GPL(crypto_transfer_aead_request_to_engine);
306 * crypto_transfer_akcipher_request_to_engine - transfer one akcipher_request
307 * to list into the engine queue
308 * @engine: the hardware engine
309 * @req: the request need to be listed into the engine queue
311 int crypto_transfer_akcipher_request_to_engine(struct crypto_engine *engine,
312 struct akcipher_request *req)
314 return crypto_transfer_request_to_engine(engine, &req->base);
316 EXPORT_SYMBOL_GPL(crypto_transfer_akcipher_request_to_engine);
319 * crypto_transfer_hash_request_to_engine - transfer one ahash_request
320 * to list into the engine queue
321 * @engine: the hardware engine
322 * @req: the request need to be listed into the engine queue
324 int crypto_transfer_hash_request_to_engine(struct crypto_engine *engine,
325 struct ahash_request *req)
327 return crypto_transfer_request_to_engine(engine, &req->base);
329 EXPORT_SYMBOL_GPL(crypto_transfer_hash_request_to_engine);
332 * crypto_transfer_skcipher_request_to_engine - transfer one skcipher_request
333 * to list into the engine queue
334 * @engine: the hardware engine
335 * @req: the request need to be listed into the engine queue
337 int crypto_transfer_skcipher_request_to_engine(struct crypto_engine *engine,
338 struct skcipher_request *req)
340 return crypto_transfer_request_to_engine(engine, &req->base);
342 EXPORT_SYMBOL_GPL(crypto_transfer_skcipher_request_to_engine);
345 * crypto_finalize_aead_request - finalize one aead_request if
346 * the request is done
347 * @engine: the hardware engine
348 * @req: the request need to be finalized
351 void crypto_finalize_aead_request(struct crypto_engine *engine,
352 struct aead_request *req, int err)
354 return crypto_finalize_request(engine, &req->base, err);
356 EXPORT_SYMBOL_GPL(crypto_finalize_aead_request);
359 * crypto_finalize_akcipher_request - finalize one akcipher_request if
360 * the request is done
361 * @engine: the hardware engine
362 * @req: the request need to be finalized
365 void crypto_finalize_akcipher_request(struct crypto_engine *engine,
366 struct akcipher_request *req, int err)
368 return crypto_finalize_request(engine, &req->base, err);
370 EXPORT_SYMBOL_GPL(crypto_finalize_akcipher_request);
373 * crypto_finalize_hash_request - finalize one ahash_request if
374 * the request is done
375 * @engine: the hardware engine
376 * @req: the request need to be finalized
379 void crypto_finalize_hash_request(struct crypto_engine *engine,
380 struct ahash_request *req, int err)
382 return crypto_finalize_request(engine, &req->base, err);
384 EXPORT_SYMBOL_GPL(crypto_finalize_hash_request);
387 * crypto_finalize_skcipher_request - finalize one skcipher_request if
388 * the request is done
389 * @engine: the hardware engine
390 * @req: the request need to be finalized
393 void crypto_finalize_skcipher_request(struct crypto_engine *engine,
394 struct skcipher_request *req, int err)
396 return crypto_finalize_request(engine, &req->base, err);
398 EXPORT_SYMBOL_GPL(crypto_finalize_skcipher_request);
401 * crypto_engine_start - start the hardware engine
402 * @engine: the hardware engine need to be started
404 * Return 0 on success, else on fail.
406 int crypto_engine_start(struct crypto_engine *engine)
410 spin_lock_irqsave(&engine->queue_lock, flags);
412 if (engine->running || engine->busy) {
413 spin_unlock_irqrestore(&engine->queue_lock, flags);
417 engine->running = true;
418 spin_unlock_irqrestore(&engine->queue_lock, flags);
420 kthread_queue_work(engine->kworker, &engine->pump_requests);
424 EXPORT_SYMBOL_GPL(crypto_engine_start);
427 * crypto_engine_stop - stop the hardware engine
428 * @engine: the hardware engine need to be stopped
430 * Return 0 on success, else on fail.
432 int crypto_engine_stop(struct crypto_engine *engine)
435 unsigned int limit = 500;
438 spin_lock_irqsave(&engine->queue_lock, flags);
441 * If the engine queue is not empty or the engine is on busy state,
442 * we need to wait for a while to pump the requests of engine queue.
444 while ((crypto_queue_len(&engine->queue) || engine->busy) && limit--) {
445 spin_unlock_irqrestore(&engine->queue_lock, flags);
447 spin_lock_irqsave(&engine->queue_lock, flags);
450 if (crypto_queue_len(&engine->queue) || engine->busy)
453 engine->running = false;
455 spin_unlock_irqrestore(&engine->queue_lock, flags);
458 dev_warn(engine->dev, "could not stop engine\n");
462 EXPORT_SYMBOL_GPL(crypto_engine_stop);
465 * crypto_engine_alloc_init_and_set - allocate crypto hardware engine structure
466 * and initialize it by setting the maximum number of entries in the software
467 * crypto-engine queue.
468 * @dev: the device attached with one hardware engine
469 * @retry_support: whether hardware has support for retry mechanism
470 * @cbk_do_batch: pointer to a callback function to be invoked when executing
471 * a batch of requests.
473 * callback(struct crypto_engine *engine)
475 * @engine: the crypto engine structure.
476 * @rt: whether this queue is set to run as a realtime task
477 * @qlen: maximum size of the crypto-engine queue
479 * This must be called from context that can sleep.
480 * Return: the crypto engine structure on success, else NULL.
482 struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
484 int (*cbk_do_batch)(struct crypto_engine *engine),
487 struct crypto_engine *engine;
492 engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL);
498 engine->running = false;
499 engine->busy = false;
500 engine->idling = false;
501 engine->retry_support = retry_support;
502 engine->priv_data = dev;
504 * Batch requests is possible only if
505 * hardware has support for retry mechanism.
507 engine->do_batch_requests = retry_support ? cbk_do_batch : NULL;
509 snprintf(engine->name, sizeof(engine->name),
510 "%s-engine", dev_name(dev));
512 crypto_init_queue(&engine->queue, qlen);
513 spin_lock_init(&engine->queue_lock);
515 engine->kworker = kthread_create_worker(0, "%s", engine->name);
516 if (IS_ERR(engine->kworker)) {
517 dev_err(dev, "failed to create crypto request pump task\n");
520 kthread_init_work(&engine->pump_requests, crypto_pump_work);
523 dev_info(dev, "will run requests pump with realtime priority\n");
524 sched_set_fifo(engine->kworker->task);
529 EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
532 * crypto_engine_alloc_init - allocate crypto hardware engine structure and
534 * @dev: the device attached with one hardware engine
535 * @rt: whether this queue is set to run as a realtime task
537 * This must be called from context that can sleep.
538 * Return: the crypto engine structure on success, else NULL.
540 struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
542 return crypto_engine_alloc_init_and_set(dev, false, NULL, rt,
543 CRYPTO_ENGINE_MAX_QLEN);
545 EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
548 * crypto_engine_exit - free the resources of hardware engine when exit
549 * @engine: the hardware engine need to be freed
551 * Return 0 for success.
553 int crypto_engine_exit(struct crypto_engine *engine)
557 ret = crypto_engine_stop(engine);
561 kthread_destroy_worker(engine->kworker);
565 EXPORT_SYMBOL_GPL(crypto_engine_exit);
567 MODULE_LICENSE("GPL");
568 MODULE_DESCRIPTION("Crypto hardware engine framework");