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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Handle async block request by crypto hardware engine.
  4 *
  5 * Copyright (C) 2016 Linaro, Inc.
  6 *
  7 * Author: Baolin Wang <baolin.wang@linaro.org>
  8 */
  9
 10#include <crypto/internal/aead.h>
 11#include <crypto/internal/akcipher.h>
 12#include <crypto/internal/engine.h>
 13#include <crypto/internal/hash.h>
 14#include <crypto/internal/kpp.h>
 15#include <crypto/internal/skcipher.h>
 16#include <linux/err.h>
 17#include <linux/delay.h>
 18#include <linux/device.h>
 19#include <linux/kernel.h>
 20#include <linux/module.h>
 21#include <uapi/linux/sched/types.h>
 22#include "internal.h"
 23
 24#define CRYPTO_ENGINE_MAX_QLEN 10
 25
 26/* Temporary algorithm flag used to indicate an updated driver. */
 27#define CRYPTO_ALG_ENGINE 0x200
 28
 29struct crypto_engine_alg {
 30	struct crypto_alg base;
 31	struct crypto_engine_op op;
 32};
 33
 34/**
 35 * crypto_finalize_request - finalize one request if the request is done
 36 * @engine: the hardware engine
 37 * @req: the request need to be finalized
 38 * @err: error number
 39 */
 40static void crypto_finalize_request(struct crypto_engine *engine,
 41				    struct crypto_async_request *req, int err)
 42{
 43	unsigned long flags;
 
 
 
 44
 45	/*
 46	 * If hardware cannot enqueue more requests
 47	 * and retry mechanism is not supported
 48	 * make sure we are completing the current request
 49	 */
 50	if (!engine->retry_support) {
 51		spin_lock_irqsave(&engine->queue_lock, flags);
 52		if (engine->cur_req == req) {
 
 53			engine->cur_req = NULL;
 54		}
 55		spin_unlock_irqrestore(&engine->queue_lock, flags);
 56	}
 57
 58	lockdep_assert_in_softirq();
 59	crypto_request_complete(req, err);
 
 
 
 
 
 
 
 
 60
 61	kthread_queue_work(engine->kworker, &engine->pump_requests);
 62}
 63
 64/**
 65 * crypto_pump_requests - dequeue one request from engine queue to process
 66 * @engine: the hardware engine
 67 * @in_kthread: true if we are in the context of the request pump thread
 68 *
 69 * This function checks if there is any request in the engine queue that
 70 * needs processing and if so call out to the driver to initialize hardware
 71 * and handle each request.
 72 */
 73static void crypto_pump_requests(struct crypto_engine *engine,
 74				 bool in_kthread)
 75{
 76	struct crypto_async_request *async_req, *backlog;
 77	struct crypto_engine_alg *alg;
 78	struct crypto_engine_op *op;
 79	unsigned long flags;
 80	bool was_busy = false;
 81	int ret;
 
 82
 83	spin_lock_irqsave(&engine->queue_lock, flags);
 84
 85	/* Make sure we are not already running a request */
 86	if (!engine->retry_support && engine->cur_req)
 87		goto out;
 88
 89	/* If another context is idling then defer */
 90	if (engine->idling) {
 91		kthread_queue_work(engine->kworker, &engine->pump_requests);
 92		goto out;
 93	}
 94
 95	/* Check if the engine queue is idle */
 96	if (!crypto_queue_len(&engine->queue) || !engine->running) {
 97		if (!engine->busy)
 98			goto out;
 99
100		/* Only do teardown in the thread */
101		if (!in_kthread) {
102			kthread_queue_work(engine->kworker,
103					   &engine->pump_requests);
104			goto out;
105		}
106
107		engine->busy = false;
108		engine->idling = true;
109		spin_unlock_irqrestore(&engine->queue_lock, flags);
110
111		if (engine->unprepare_crypt_hardware &&
112		    engine->unprepare_crypt_hardware(engine))
113			dev_err(engine->dev, "failed to unprepare crypt hardware\n");
114
115		spin_lock_irqsave(&engine->queue_lock, flags);
116		engine->idling = false;
117		goto out;
118	}
119
120start_request:
121	/* Get the fist request from the engine queue to handle */
122	backlog = crypto_get_backlog(&engine->queue);
123	async_req = crypto_dequeue_request(&engine->queue);
124	if (!async_req)
125		goto out;
126
127	/*
128	 * If hardware doesn't support the retry mechanism,
129	 * keep track of the request we are processing now.
130	 * We'll need it on completion (crypto_finalize_request).
131	 */
132	if (!engine->retry_support)
133		engine->cur_req = async_req;
134
 
 
 
135	if (engine->busy)
136		was_busy = true;
137	else
138		engine->busy = true;
139
140	spin_unlock_irqrestore(&engine->queue_lock, flags);
141
142	/* Until here we get the request need to be encrypted successfully */
143	if (!was_busy && engine->prepare_crypt_hardware) {
144		ret = engine->prepare_crypt_hardware(engine);
145		if (ret) {
146			dev_err(engine->dev, "failed to prepare crypt hardware\n");
147			goto req_err_1;
148		}
149	}
150
151	if (async_req->tfm->__crt_alg->cra_flags & CRYPTO_ALG_ENGINE) {
152		alg = container_of(async_req->tfm->__crt_alg,
153				   struct crypto_engine_alg, base);
154		op = &alg->op;
155	} else {
 
 
 
 
 
 
156		dev_err(engine->dev, "failed to do request\n");
157		ret = -EINVAL;
158		goto req_err_1;
159	}
160
161	ret = op->do_one_request(engine, async_req);
162
163	/* Request unsuccessfully executed by hardware */
164	if (ret < 0) {
165		/*
166		 * If hardware queue is full (-ENOSPC), requeue request
167		 * regardless of backlog flag.
168		 * Otherwise, unprepare and complete the request.
169		 */
170		if (!engine->retry_support ||
171		    (ret != -ENOSPC)) {
172			dev_err(engine->dev,
173				"Failed to do one request from queue: %d\n",
174				ret);
175			goto req_err_1;
176		}
 
 
 
 
 
 
 
 
 
 
 
 
177		spin_lock_irqsave(&engine->queue_lock, flags);
178		/*
179		 * If hardware was unable to execute request, enqueue it
180		 * back in front of crypto-engine queue, to keep the order
181		 * of requests.
182		 */
183		crypto_enqueue_request_head(&engine->queue, async_req);
184
185		kthread_queue_work(engine->kworker, &engine->pump_requests);
186		goto out;
187	}
188
189	goto retry;
190
191req_err_1:
192	crypto_request_complete(async_req, ret);
 
 
 
 
193
194retry:
195	if (backlog)
196		crypto_request_complete(backlog, -EINPROGRESS);
197
 
198	/* If retry mechanism is supported, send new requests to engine */
199	if (engine->retry_support) {
200		spin_lock_irqsave(&engine->queue_lock, flags);
201		goto start_request;
202	}
203	return;
204
205out:
206	spin_unlock_irqrestore(&engine->queue_lock, flags);
207
208	/*
209	 * Batch requests is possible only if
210	 * hardware can enqueue multiple requests
211	 */
212	if (engine->do_batch_requests) {
213		ret = engine->do_batch_requests(engine);
214		if (ret)
215			dev_err(engine->dev, "failed to do batch requests: %d\n",
216				ret);
217	}
218
219	return;
220}
221
222static void crypto_pump_work(struct kthread_work *work)
223{
224	struct crypto_engine *engine =
225		container_of(work, struct crypto_engine, pump_requests);
226
227	crypto_pump_requests(engine, true);
228}
229
230/**
231 * crypto_transfer_request - transfer the new request into the engine queue
232 * @engine: the hardware engine
233 * @req: the request need to be listed into the engine queue
234 * @need_pump: indicates whether queue the pump of request to kthread_work
235 */
236static int crypto_transfer_request(struct crypto_engine *engine,
237				   struct crypto_async_request *req,
238				   bool need_pump)
239{
240	unsigned long flags;
241	int ret;
242
243	spin_lock_irqsave(&engine->queue_lock, flags);
244
245	if (!engine->running) {
246		spin_unlock_irqrestore(&engine->queue_lock, flags);
247		return -ESHUTDOWN;
248	}
249
250	ret = crypto_enqueue_request(&engine->queue, req);
251
252	if (!engine->busy && need_pump)
253		kthread_queue_work(engine->kworker, &engine->pump_requests);
254
255	spin_unlock_irqrestore(&engine->queue_lock, flags);
256	return ret;
257}
258
259/**
260 * crypto_transfer_request_to_engine - transfer one request to list
261 * into the engine queue
262 * @engine: the hardware engine
263 * @req: the request need to be listed into the engine queue
264 */
265static int crypto_transfer_request_to_engine(struct crypto_engine *engine,
266					     struct crypto_async_request *req)
267{
268	return crypto_transfer_request(engine, req, true);
269}
270
271/**
272 * crypto_transfer_aead_request_to_engine - transfer one aead_request
273 * to list into the engine queue
274 * @engine: the hardware engine
275 * @req: the request need to be listed into the engine queue
276 */
277int crypto_transfer_aead_request_to_engine(struct crypto_engine *engine,
278					   struct aead_request *req)
279{
280	return crypto_transfer_request_to_engine(engine, &req->base);
281}
282EXPORT_SYMBOL_GPL(crypto_transfer_aead_request_to_engine);
283
284/**
285 * crypto_transfer_akcipher_request_to_engine - transfer one akcipher_request
286 * to list into the engine queue
287 * @engine: the hardware engine
288 * @req: the request need to be listed into the engine queue
289 */
290int crypto_transfer_akcipher_request_to_engine(struct crypto_engine *engine,
291					       struct akcipher_request *req)
292{
293	return crypto_transfer_request_to_engine(engine, &req->base);
294}
295EXPORT_SYMBOL_GPL(crypto_transfer_akcipher_request_to_engine);
296
297/**
298 * crypto_transfer_hash_request_to_engine - transfer one ahash_request
299 * to list into the engine queue
300 * @engine: the hardware engine
301 * @req: the request need to be listed into the engine queue
302 */
303int crypto_transfer_hash_request_to_engine(struct crypto_engine *engine,
304					   struct ahash_request *req)
305{
306	return crypto_transfer_request_to_engine(engine, &req->base);
307}
308EXPORT_SYMBOL_GPL(crypto_transfer_hash_request_to_engine);
309
310/**
311 * crypto_transfer_kpp_request_to_engine - transfer one kpp_request to list
312 * into the engine queue
313 * @engine: the hardware engine
314 * @req: the request need to be listed into the engine queue
315 */
316int crypto_transfer_kpp_request_to_engine(struct crypto_engine *engine,
317					  struct kpp_request *req)
318{
319	return crypto_transfer_request_to_engine(engine, &req->base);
320}
321EXPORT_SYMBOL_GPL(crypto_transfer_kpp_request_to_engine);
322
323/**
324 * crypto_transfer_skcipher_request_to_engine - transfer one skcipher_request
325 * to list into the engine queue
326 * @engine: the hardware engine
327 * @req: the request need to be listed into the engine queue
328 */
329int crypto_transfer_skcipher_request_to_engine(struct crypto_engine *engine,
330					       struct skcipher_request *req)
331{
332	return crypto_transfer_request_to_engine(engine, &req->base);
333}
334EXPORT_SYMBOL_GPL(crypto_transfer_skcipher_request_to_engine);
335
336/**
337 * crypto_finalize_aead_request - finalize one aead_request if
338 * the request is done
339 * @engine: the hardware engine
340 * @req: the request need to be finalized
341 * @err: error number
342 */
343void crypto_finalize_aead_request(struct crypto_engine *engine,
344				  struct aead_request *req, int err)
345{
346	return crypto_finalize_request(engine, &req->base, err);
347}
348EXPORT_SYMBOL_GPL(crypto_finalize_aead_request);
349
350/**
351 * crypto_finalize_akcipher_request - finalize one akcipher_request if
352 * the request is done
353 * @engine: the hardware engine
354 * @req: the request need to be finalized
355 * @err: error number
356 */
357void crypto_finalize_akcipher_request(struct crypto_engine *engine,
358				      struct akcipher_request *req, int err)
359{
360	return crypto_finalize_request(engine, &req->base, err);
361}
362EXPORT_SYMBOL_GPL(crypto_finalize_akcipher_request);
363
364/**
365 * crypto_finalize_hash_request - finalize one ahash_request if
366 * the request is done
367 * @engine: the hardware engine
368 * @req: the request need to be finalized
369 * @err: error number
370 */
371void crypto_finalize_hash_request(struct crypto_engine *engine,
372				  struct ahash_request *req, int err)
373{
374	return crypto_finalize_request(engine, &req->base, err);
375}
376EXPORT_SYMBOL_GPL(crypto_finalize_hash_request);
377
378/**
379 * crypto_finalize_kpp_request - finalize one kpp_request if the request is done
380 * @engine: the hardware engine
381 * @req: the request need to be finalized
382 * @err: error number
383 */
384void crypto_finalize_kpp_request(struct crypto_engine *engine,
385				 struct kpp_request *req, int err)
386{
387	return crypto_finalize_request(engine, &req->base, err);
388}
389EXPORT_SYMBOL_GPL(crypto_finalize_kpp_request);
390
391/**
392 * crypto_finalize_skcipher_request - finalize one skcipher_request if
393 * the request is done
394 * @engine: the hardware engine
395 * @req: the request need to be finalized
396 * @err: error number
397 */
398void crypto_finalize_skcipher_request(struct crypto_engine *engine,
399				      struct skcipher_request *req, int err)
400{
401	return crypto_finalize_request(engine, &req->base, err);
402}
403EXPORT_SYMBOL_GPL(crypto_finalize_skcipher_request);
404
405/**
406 * crypto_engine_start - start the hardware engine
407 * @engine: the hardware engine need to be started
408 *
409 * Return 0 on success, else on fail.
410 */
411int crypto_engine_start(struct crypto_engine *engine)
412{
413	unsigned long flags;
414
415	spin_lock_irqsave(&engine->queue_lock, flags);
416
417	if (engine->running || engine->busy) {
418		spin_unlock_irqrestore(&engine->queue_lock, flags);
419		return -EBUSY;
420	}
421
422	engine->running = true;
423	spin_unlock_irqrestore(&engine->queue_lock, flags);
424
425	kthread_queue_work(engine->kworker, &engine->pump_requests);
426
427	return 0;
428}
429EXPORT_SYMBOL_GPL(crypto_engine_start);
430
431/**
432 * crypto_engine_stop - stop the hardware engine
433 * @engine: the hardware engine need to be stopped
434 *
435 * Return 0 on success, else on fail.
436 */
437int crypto_engine_stop(struct crypto_engine *engine)
438{
439	unsigned long flags;
440	unsigned int limit = 500;
441	int ret = 0;
442
443	spin_lock_irqsave(&engine->queue_lock, flags);
444
445	/*
446	 * If the engine queue is not empty or the engine is on busy state,
447	 * we need to wait for a while to pump the requests of engine queue.
448	 */
449	while ((crypto_queue_len(&engine->queue) || engine->busy) && limit--) {
450		spin_unlock_irqrestore(&engine->queue_lock, flags);
451		msleep(20);
452		spin_lock_irqsave(&engine->queue_lock, flags);
453	}
454
455	if (crypto_queue_len(&engine->queue) || engine->busy)
456		ret = -EBUSY;
457	else
458		engine->running = false;
459
460	spin_unlock_irqrestore(&engine->queue_lock, flags);
461
462	if (ret)
463		dev_warn(engine->dev, "could not stop engine\n");
464
465	return ret;
466}
467EXPORT_SYMBOL_GPL(crypto_engine_stop);
468
469/**
470 * crypto_engine_alloc_init_and_set - allocate crypto hardware engine structure
471 * and initialize it by setting the maximum number of entries in the software
472 * crypto-engine queue.
473 * @dev: the device attached with one hardware engine
474 * @retry_support: whether hardware has support for retry mechanism
475 * @cbk_do_batch: pointer to a callback function to be invoked when executing
476 *                a batch of requests.
477 *                This has the form:
478 *                callback(struct crypto_engine *engine)
479 *                where:
480 *                engine: the crypto engine structure.
481 * @rt: whether this queue is set to run as a realtime task
482 * @qlen: maximum size of the crypto-engine queue
483 *
484 * This must be called from context that can sleep.
485 * Return: the crypto engine structure on success, else NULL.
486 */
487struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
488						       bool retry_support,
489						       int (*cbk_do_batch)(struct crypto_engine *engine),
490						       bool rt, int qlen)
491{
492	struct crypto_engine *engine;
493
494	if (!dev)
495		return NULL;
496
497	engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL);
498	if (!engine)
499		return NULL;
500
501	engine->dev = dev;
502	engine->rt = rt;
503	engine->running = false;
504	engine->busy = false;
505	engine->idling = false;
506	engine->retry_support = retry_support;
507	engine->priv_data = dev;
508	/*
509	 * Batch requests is possible only if
510	 * hardware has support for retry mechanism.
511	 */
512	engine->do_batch_requests = retry_support ? cbk_do_batch : NULL;
513
514	snprintf(engine->name, sizeof(engine->name),
515		 "%s-engine", dev_name(dev));
516
517	crypto_init_queue(&engine->queue, qlen);
518	spin_lock_init(&engine->queue_lock);
519
520	engine->kworker = kthread_create_worker(0, "%s", engine->name);
521	if (IS_ERR(engine->kworker)) {
522		dev_err(dev, "failed to create crypto request pump task\n");
523		return NULL;
524	}
525	kthread_init_work(&engine->pump_requests, crypto_pump_work);
526
527	if (engine->rt) {
528		dev_info(dev, "will run requests pump with realtime priority\n");
529		sched_set_fifo(engine->kworker->task);
530	}
531
532	return engine;
533}
534EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
535
536/**
537 * crypto_engine_alloc_init - allocate crypto hardware engine structure and
538 * initialize it.
539 * @dev: the device attached with one hardware engine
540 * @rt: whether this queue is set to run as a realtime task
541 *
542 * This must be called from context that can sleep.
543 * Return: the crypto engine structure on success, else NULL.
544 */
545struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
546{
547	return crypto_engine_alloc_init_and_set(dev, false, NULL, rt,
548						CRYPTO_ENGINE_MAX_QLEN);
549}
550EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
551
552/**
553 * crypto_engine_exit - free the resources of hardware engine when exit
554 * @engine: the hardware engine need to be freed
 
 
555 */
556void crypto_engine_exit(struct crypto_engine *engine)
557{
558	int ret;
559
560	ret = crypto_engine_stop(engine);
561	if (ret)
562		return;
563
564	kthread_destroy_worker(engine->kworker);
565}
566EXPORT_SYMBOL_GPL(crypto_engine_exit);
567
568int crypto_engine_register_aead(struct aead_engine_alg *alg)
569{
570	if (!alg->op.do_one_request)
571		return -EINVAL;
572
573	alg->base.base.cra_flags |= CRYPTO_ALG_ENGINE;
574
575	return crypto_register_aead(&alg->base);
576}
577EXPORT_SYMBOL_GPL(crypto_engine_register_aead);
578
579void crypto_engine_unregister_aead(struct aead_engine_alg *alg)
580{
581	crypto_unregister_aead(&alg->base);
582}
583EXPORT_SYMBOL_GPL(crypto_engine_unregister_aead);
584
585int crypto_engine_register_aeads(struct aead_engine_alg *algs, int count)
586{
587	int i, ret;
588
589	for (i = 0; i < count; i++) {
590		ret = crypto_engine_register_aead(&algs[i]);
591		if (ret)
592			goto err;
593	}
594
595	return 0;
596
597err:
598	crypto_engine_unregister_aeads(algs, i);
599
600	return ret;
601}
602EXPORT_SYMBOL_GPL(crypto_engine_register_aeads);
603
604void crypto_engine_unregister_aeads(struct aead_engine_alg *algs, int count)
605{
606	int i;
607
608	for (i = count - 1; i >= 0; --i)
609		crypto_engine_unregister_aead(&algs[i]);
610}
611EXPORT_SYMBOL_GPL(crypto_engine_unregister_aeads);
612
613int crypto_engine_register_ahash(struct ahash_engine_alg *alg)
614{
615	if (!alg->op.do_one_request)
616		return -EINVAL;
617
618	alg->base.halg.base.cra_flags |= CRYPTO_ALG_ENGINE;
619
620	return crypto_register_ahash(&alg->base);
621}
622EXPORT_SYMBOL_GPL(crypto_engine_register_ahash);
623
624void crypto_engine_unregister_ahash(struct ahash_engine_alg *alg)
625{
626	crypto_unregister_ahash(&alg->base);
627}
628EXPORT_SYMBOL_GPL(crypto_engine_unregister_ahash);
629
630int crypto_engine_register_ahashes(struct ahash_engine_alg *algs, int count)
631{
632	int i, ret;
633
634	for (i = 0; i < count; i++) {
635		ret = crypto_engine_register_ahash(&algs[i]);
636		if (ret)
637			goto err;
638	}
639
640	return 0;
641
642err:
643	crypto_engine_unregister_ahashes(algs, i);
644
645	return ret;
646}
647EXPORT_SYMBOL_GPL(crypto_engine_register_ahashes);
648
649void crypto_engine_unregister_ahashes(struct ahash_engine_alg *algs,
650				      int count)
651{
652	int i;
653
654	for (i = count - 1; i >= 0; --i)
655		crypto_engine_unregister_ahash(&algs[i]);
656}
657EXPORT_SYMBOL_GPL(crypto_engine_unregister_ahashes);
658
659int crypto_engine_register_akcipher(struct akcipher_engine_alg *alg)
660{
661	if (!alg->op.do_one_request)
662		return -EINVAL;
663
664	alg->base.base.cra_flags |= CRYPTO_ALG_ENGINE;
665
666	return crypto_register_akcipher(&alg->base);
667}
668EXPORT_SYMBOL_GPL(crypto_engine_register_akcipher);
669
670void crypto_engine_unregister_akcipher(struct akcipher_engine_alg *alg)
671{
672	crypto_unregister_akcipher(&alg->base);
673}
674EXPORT_SYMBOL_GPL(crypto_engine_unregister_akcipher);
675
676int crypto_engine_register_kpp(struct kpp_engine_alg *alg)
677{
678	if (!alg->op.do_one_request)
679		return -EINVAL;
680
681	alg->base.base.cra_flags |= CRYPTO_ALG_ENGINE;
682
683	return crypto_register_kpp(&alg->base);
684}
685EXPORT_SYMBOL_GPL(crypto_engine_register_kpp);
686
687void crypto_engine_unregister_kpp(struct kpp_engine_alg *alg)
688{
689	crypto_unregister_kpp(&alg->base);
690}
691EXPORT_SYMBOL_GPL(crypto_engine_unregister_kpp);
692
693int crypto_engine_register_skcipher(struct skcipher_engine_alg *alg)
694{
695	if (!alg->op.do_one_request)
696		return -EINVAL;
697
698	alg->base.base.cra_flags |= CRYPTO_ALG_ENGINE;
699
700	return crypto_register_skcipher(&alg->base);
701}
702EXPORT_SYMBOL_GPL(crypto_engine_register_skcipher);
703
704void crypto_engine_unregister_skcipher(struct skcipher_engine_alg *alg)
705{
706	return crypto_unregister_skcipher(&alg->base);
707}
708EXPORT_SYMBOL_GPL(crypto_engine_unregister_skcipher);
709
710int crypto_engine_register_skciphers(struct skcipher_engine_alg *algs,
711				     int count)
712{
713	int i, ret;
714
715	for (i = 0; i < count; i++) {
716		ret = crypto_engine_register_skcipher(&algs[i]);
717		if (ret)
718			goto err;
719	}
720
721	return 0;
722
723err:
724	crypto_engine_unregister_skciphers(algs, i);
725
726	return ret;
727}
728EXPORT_SYMBOL_GPL(crypto_engine_register_skciphers);
729
730void crypto_engine_unregister_skciphers(struct skcipher_engine_alg *algs,
731					int count)
732{
733	int i;
734
735	for (i = count - 1; i >= 0; --i)
736		crypto_engine_unregister_skcipher(&algs[i]);
737}
738EXPORT_SYMBOL_GPL(crypto_engine_unregister_skciphers);
739
740MODULE_LICENSE("GPL");
741MODULE_DESCRIPTION("Crypto hardware engine framework");
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * Handle async block request by crypto hardware engine.
  4 *
  5 * Copyright (C) 2016 Linaro, Inc.
  6 *
  7 * Author: Baolin Wang <baolin.wang@linaro.org>
  8 */
  9
 
 
 
 
 
 
 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>
 15#include "internal.h"
 16
 17#define CRYPTO_ENGINE_MAX_QLEN 10
 18
 
 
 
 
 
 
 
 
 19/**
 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
 23 * @err: error number
 24 */
 25static void crypto_finalize_request(struct crypto_engine *engine,
 26				    struct crypto_async_request *req, int err)
 27{
 28	unsigned long flags;
 29	bool finalize_req = false;
 30	int ret;
 31	struct crypto_engine_ctx *enginectx;
 32
 33	/*
 34	 * If hardware cannot enqueue more requests
 35	 * and retry mechanism is not supported
 36	 * make sure we are completing the current request
 37	 */
 38	if (!engine->retry_support) {
 39		spin_lock_irqsave(&engine->queue_lock, flags);
 40		if (engine->cur_req == req) {
 41			finalize_req = true;
 42			engine->cur_req = NULL;
 43		}
 44		spin_unlock_irqrestore(&engine->queue_lock, flags);
 45	}
 46
 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);
 52			if (ret)
 53				dev_err(engine->dev, "failed to unprepare request\n");
 54		}
 55	}
 56	req->complete(req, err);
 57
 58	kthread_queue_work(engine->kworker, &engine->pump_requests);
 59}
 60
 61/**
 62 * crypto_pump_requests - dequeue one request from engine queue to process
 63 * @engine: the hardware engine
 64 * @in_kthread: true if we are in the context of the request pump thread
 65 *
 66 * This function checks if there is any request in the engine queue that
 67 * needs processing and if so call out to the driver to initialize hardware
 68 * and handle each request.
 69 */
 70static void crypto_pump_requests(struct crypto_engine *engine,
 71				 bool in_kthread)
 72{
 73	struct crypto_async_request *async_req, *backlog;
 
 
 74	unsigned long flags;
 75	bool was_busy = false;
 76	int ret;
 77	struct crypto_engine_ctx *enginectx;
 78
 79	spin_lock_irqsave(&engine->queue_lock, flags);
 80
 81	/* Make sure we are not already running a request */
 82	if (!engine->retry_support && engine->cur_req)
 83		goto out;
 84
 85	/* If another context is idling then defer */
 86	if (engine->idling) {
 87		kthread_queue_work(engine->kworker, &engine->pump_requests);
 88		goto out;
 89	}
 90
 91	/* Check if the engine queue is idle */
 92	if (!crypto_queue_len(&engine->queue) || !engine->running) {
 93		if (!engine->busy)
 94			goto out;
 95
 96		/* Only do teardown in the thread */
 97		if (!in_kthread) {
 98			kthread_queue_work(engine->kworker,
 99					   &engine->pump_requests);
100			goto out;
101		}
102
103		engine->busy = false;
104		engine->idling = true;
105		spin_unlock_irqrestore(&engine->queue_lock, flags);
106
107		if (engine->unprepare_crypt_hardware &&
108		    engine->unprepare_crypt_hardware(engine))
109			dev_err(engine->dev, "failed to unprepare crypt hardware\n");
110
111		spin_lock_irqsave(&engine->queue_lock, flags);
112		engine->idling = false;
113		goto out;
114	}
115
116start_request:
117	/* Get the fist request from the engine queue to handle */
118	backlog = crypto_get_backlog(&engine->queue);
119	async_req = crypto_dequeue_request(&engine->queue);
120	if (!async_req)
121		goto out;
122
123	/*
124	 * If hardware doesn't support the retry mechanism,
125	 * keep track of the request we are processing now.
126	 * We'll need it on completion (crypto_finalize_request).
127	 */
128	if (!engine->retry_support)
129		engine->cur_req = async_req;
130
131	if (backlog)
132		backlog->complete(backlog, -EINPROGRESS);
133
134	if (engine->busy)
135		was_busy = true;
136	else
137		engine->busy = true;
138
139	spin_unlock_irqrestore(&engine->queue_lock, flags);
140
141	/* Until here we get the request need to be encrypted successfully */
142	if (!was_busy && engine->prepare_crypt_hardware) {
143		ret = engine->prepare_crypt_hardware(engine);
144		if (ret) {
145			dev_err(engine->dev, "failed to prepare crypt hardware\n");
146			goto req_err_2;
147		}
148	}
149
150	enginectx = crypto_tfm_ctx(async_req->tfm);
151
152	if (enginectx->op.prepare_request) {
153		ret = enginectx->op.prepare_request(engine, async_req);
154		if (ret) {
155			dev_err(engine->dev, "failed to prepare request: %d\n",
156				ret);
157			goto req_err_2;
158		}
159	}
160	if (!enginectx->op.do_one_request) {
161		dev_err(engine->dev, "failed to do request\n");
162		ret = -EINVAL;
163		goto req_err_1;
164	}
165
166	ret = enginectx->op.do_one_request(engine, async_req);
167
168	/* Request unsuccessfully executed by hardware */
169	if (ret < 0) {
170		/*
171		 * If hardware queue is full (-ENOSPC), requeue request
172		 * regardless of backlog flag.
173		 * Otherwise, unprepare and complete the request.
174		 */
175		if (!engine->retry_support ||
176		    (ret != -ENOSPC)) {
177			dev_err(engine->dev,
178				"Failed to do one request from queue: %d\n",
179				ret);
180			goto req_err_1;
181		}
182		/*
183		 * If retry mechanism is supported,
184		 * unprepare current request and
185		 * enqueue it back into crypto-engine queue.
186		 */
187		if (enginectx->op.unprepare_request) {
188			ret = enginectx->op.unprepare_request(engine,
189							      async_req);
190			if (ret)
191				dev_err(engine->dev,
192					"failed to unprepare request\n");
193		}
194		spin_lock_irqsave(&engine->queue_lock, flags);
195		/*
196		 * If hardware was unable to execute request, enqueue it
197		 * back in front of crypto-engine queue, to keep the order
198		 * of requests.
199		 */
200		crypto_enqueue_request_head(&engine->queue, async_req);
201
202		kthread_queue_work(engine->kworker, &engine->pump_requests);
203		goto out;
204	}
205
206	goto retry;
207
208req_err_1:
209	if (enginectx->op.unprepare_request) {
210		ret = enginectx->op.unprepare_request(engine, async_req);
211		if (ret)
212			dev_err(engine->dev, "failed to unprepare request\n");
213	}
214
215req_err_2:
216	async_req->complete(async_req, ret);
 
217
218retry:
219	/* If retry mechanism is supported, send new requests to engine */
220	if (engine->retry_support) {
221		spin_lock_irqsave(&engine->queue_lock, flags);
222		goto start_request;
223	}
224	return;
225
226out:
227	spin_unlock_irqrestore(&engine->queue_lock, flags);
228
229	/*
230	 * Batch requests is possible only if
231	 * hardware can enqueue multiple requests
232	 */
233	if (engine->do_batch_requests) {
234		ret = engine->do_batch_requests(engine);
235		if (ret)
236			dev_err(engine->dev, "failed to do batch requests: %d\n",
237				ret);
238	}
239
240	return;
241}
242
243static void crypto_pump_work(struct kthread_work *work)
244{
245	struct crypto_engine *engine =
246		container_of(work, struct crypto_engine, pump_requests);
247
248	crypto_pump_requests(engine, true);
249}
250
251/**
252 * crypto_transfer_request - transfer the new request into the engine queue
253 * @engine: the hardware engine
254 * @req: the request need to be listed into the engine queue
 
255 */
256static int crypto_transfer_request(struct crypto_engine *engine,
257				   struct crypto_async_request *req,
258				   bool need_pump)
259{
260	unsigned long flags;
261	int ret;
262
263	spin_lock_irqsave(&engine->queue_lock, flags);
264
265	if (!engine->running) {
266		spin_unlock_irqrestore(&engine->queue_lock, flags);
267		return -ESHUTDOWN;
268	}
269
270	ret = crypto_enqueue_request(&engine->queue, req);
271
272	if (!engine->busy && need_pump)
273		kthread_queue_work(engine->kworker, &engine->pump_requests);
274
275	spin_unlock_irqrestore(&engine->queue_lock, flags);
276	return ret;
277}
278
279/**
280 * crypto_transfer_request_to_engine - transfer one request to list
281 * into the engine queue
282 * @engine: the hardware engine
283 * @req: the request need to be listed into the engine queue
284 */
285static int crypto_transfer_request_to_engine(struct crypto_engine *engine,
286					     struct crypto_async_request *req)
287{
288	return crypto_transfer_request(engine, req, true);
289}
290
291/**
292 * crypto_transfer_aead_request_to_engine - transfer one aead_request
293 * to list into the engine queue
294 * @engine: the hardware engine
295 * @req: the request need to be listed into the engine queue
296 */
297int crypto_transfer_aead_request_to_engine(struct crypto_engine *engine,
298					   struct aead_request *req)
299{
300	return crypto_transfer_request_to_engine(engine, &req->base);
301}
302EXPORT_SYMBOL_GPL(crypto_transfer_aead_request_to_engine);
303
304/**
305 * crypto_transfer_akcipher_request_to_engine - transfer one akcipher_request
306 * to list into the engine queue
307 * @engine: the hardware engine
308 * @req: the request need to be listed into the engine queue
309 */
310int crypto_transfer_akcipher_request_to_engine(struct crypto_engine *engine,
311					       struct akcipher_request *req)
312{
313	return crypto_transfer_request_to_engine(engine, &req->base);
314}
315EXPORT_SYMBOL_GPL(crypto_transfer_akcipher_request_to_engine);
316
317/**
318 * crypto_transfer_hash_request_to_engine - transfer one ahash_request
319 * to list into the engine queue
320 * @engine: the hardware engine
321 * @req: the request need to be listed into the engine queue
322 */
323int crypto_transfer_hash_request_to_engine(struct crypto_engine *engine,
324					   struct ahash_request *req)
325{
326	return crypto_transfer_request_to_engine(engine, &req->base);
327}
328EXPORT_SYMBOL_GPL(crypto_transfer_hash_request_to_engine);
329
330/**
 
 
 
 
 
 
 
 
 
 
 
 
 
331 * crypto_transfer_skcipher_request_to_engine - transfer one skcipher_request
332 * to list into the engine queue
333 * @engine: the hardware engine
334 * @req: the request need to be listed into the engine queue
335 */
336int crypto_transfer_skcipher_request_to_engine(struct crypto_engine *engine,
337					       struct skcipher_request *req)
338{
339	return crypto_transfer_request_to_engine(engine, &req->base);
340}
341EXPORT_SYMBOL_GPL(crypto_transfer_skcipher_request_to_engine);
342
343/**
344 * crypto_finalize_aead_request - finalize one aead_request if
345 * the request is done
346 * @engine: the hardware engine
347 * @req: the request need to be finalized
348 * @err: error number
349 */
350void crypto_finalize_aead_request(struct crypto_engine *engine,
351				  struct aead_request *req, int err)
352{
353	return crypto_finalize_request(engine, &req->base, err);
354}
355EXPORT_SYMBOL_GPL(crypto_finalize_aead_request);
356
357/**
358 * crypto_finalize_akcipher_request - finalize one akcipher_request if
359 * the request is done
360 * @engine: the hardware engine
361 * @req: the request need to be finalized
362 * @err: error number
363 */
364void crypto_finalize_akcipher_request(struct crypto_engine *engine,
365				      struct akcipher_request *req, int err)
366{
367	return crypto_finalize_request(engine, &req->base, err);
368}
369EXPORT_SYMBOL_GPL(crypto_finalize_akcipher_request);
370
371/**
372 * crypto_finalize_hash_request - finalize one ahash_request if
373 * the request is done
374 * @engine: the hardware engine
375 * @req: the request need to be finalized
376 * @err: error number
377 */
378void crypto_finalize_hash_request(struct crypto_engine *engine,
379				  struct ahash_request *req, int err)
380{
381	return crypto_finalize_request(engine, &req->base, err);
382}
383EXPORT_SYMBOL_GPL(crypto_finalize_hash_request);
384
385/**
 
 
 
 
 
 
 
 
 
 
 
 
 
386 * crypto_finalize_skcipher_request - finalize one skcipher_request if
387 * the request is done
388 * @engine: the hardware engine
389 * @req: the request need to be finalized
390 * @err: error number
391 */
392void crypto_finalize_skcipher_request(struct crypto_engine *engine,
393				      struct skcipher_request *req, int err)
394{
395	return crypto_finalize_request(engine, &req->base, err);
396}
397EXPORT_SYMBOL_GPL(crypto_finalize_skcipher_request);
398
399/**
400 * crypto_engine_start - start the hardware engine
401 * @engine: the hardware engine need to be started
402 *
403 * Return 0 on success, else on fail.
404 */
405int crypto_engine_start(struct crypto_engine *engine)
406{
407	unsigned long flags;
408
409	spin_lock_irqsave(&engine->queue_lock, flags);
410
411	if (engine->running || engine->busy) {
412		spin_unlock_irqrestore(&engine->queue_lock, flags);
413		return -EBUSY;
414	}
415
416	engine->running = true;
417	spin_unlock_irqrestore(&engine->queue_lock, flags);
418
419	kthread_queue_work(engine->kworker, &engine->pump_requests);
420
421	return 0;
422}
423EXPORT_SYMBOL_GPL(crypto_engine_start);
424
425/**
426 * crypto_engine_stop - stop the hardware engine
427 * @engine: the hardware engine need to be stopped
428 *
429 * Return 0 on success, else on fail.
430 */
431int crypto_engine_stop(struct crypto_engine *engine)
432{
433	unsigned long flags;
434	unsigned int limit = 500;
435	int ret = 0;
436
437	spin_lock_irqsave(&engine->queue_lock, flags);
438
439	/*
440	 * If the engine queue is not empty or the engine is on busy state,
441	 * we need to wait for a while to pump the requests of engine queue.
442	 */
443	while ((crypto_queue_len(&engine->queue) || engine->busy) && limit--) {
444		spin_unlock_irqrestore(&engine->queue_lock, flags);
445		msleep(20);
446		spin_lock_irqsave(&engine->queue_lock, flags);
447	}
448
449	if (crypto_queue_len(&engine->queue) || engine->busy)
450		ret = -EBUSY;
451	else
452		engine->running = false;
453
454	spin_unlock_irqrestore(&engine->queue_lock, flags);
455
456	if (ret)
457		dev_warn(engine->dev, "could not stop engine\n");
458
459	return ret;
460}
461EXPORT_SYMBOL_GPL(crypto_engine_stop);
462
463/**
464 * crypto_engine_alloc_init_and_set - allocate crypto hardware engine structure
465 * and initialize it by setting the maximum number of entries in the software
466 * crypto-engine queue.
467 * @dev: the device attached with one hardware engine
468 * @retry_support: whether hardware has support for retry mechanism
469 * @cbk_do_batch: pointer to a callback function to be invoked when executing
470 *                a batch of requests.
471 *                This has the form:
472 *                callback(struct crypto_engine *engine)
473 *                where:
474 *                @engine: the crypto engine structure.
475 * @rt: whether this queue is set to run as a realtime task
476 * @qlen: maximum size of the crypto-engine queue
477 *
478 * This must be called from context that can sleep.
479 * Return: the crypto engine structure on success, else NULL.
480 */
481struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
482						       bool retry_support,
483						       int (*cbk_do_batch)(struct crypto_engine *engine),
484						       bool rt, int qlen)
485{
486	struct crypto_engine *engine;
487
488	if (!dev)
489		return NULL;
490
491	engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL);
492	if (!engine)
493		return NULL;
494
495	engine->dev = dev;
496	engine->rt = rt;
497	engine->running = false;
498	engine->busy = false;
499	engine->idling = false;
500	engine->retry_support = retry_support;
501	engine->priv_data = dev;
502	/*
503	 * Batch requests is possible only if
504	 * hardware has support for retry mechanism.
505	 */
506	engine->do_batch_requests = retry_support ? cbk_do_batch : NULL;
507
508	snprintf(engine->name, sizeof(engine->name),
509		 "%s-engine", dev_name(dev));
510
511	crypto_init_queue(&engine->queue, qlen);
512	spin_lock_init(&engine->queue_lock);
513
514	engine->kworker = kthread_create_worker(0, "%s", engine->name);
515	if (IS_ERR(engine->kworker)) {
516		dev_err(dev, "failed to create crypto request pump task\n");
517		return NULL;
518	}
519	kthread_init_work(&engine->pump_requests, crypto_pump_work);
520
521	if (engine->rt) {
522		dev_info(dev, "will run requests pump with realtime priority\n");
523		sched_set_fifo(engine->kworker->task);
524	}
525
526	return engine;
527}
528EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
529
530/**
531 * crypto_engine_alloc_init - allocate crypto hardware engine structure and
532 * initialize it.
533 * @dev: the device attached with one hardware engine
534 * @rt: whether this queue is set to run as a realtime task
535 *
536 * This must be called from context that can sleep.
537 * Return: the crypto engine structure on success, else NULL.
538 */
539struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
540{
541	return crypto_engine_alloc_init_and_set(dev, false, NULL, rt,
542						CRYPTO_ENGINE_MAX_QLEN);
543}
544EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
545
546/**
547 * crypto_engine_exit - free the resources of hardware engine when exit
548 * @engine: the hardware engine need to be freed
549 *
550 * Return 0 for success.
551 */
552int crypto_engine_exit(struct crypto_engine *engine)
553{
554	int ret;
555
556	ret = crypto_engine_stop(engine);
557	if (ret)
558		return ret;
559
560	kthread_destroy_worker(engine->kworker);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
561
562	return 0;
 
 
 
 
 
563}
564EXPORT_SYMBOL_GPL(crypto_engine_exit);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
565
566MODULE_LICENSE("GPL");
567MODULE_DESCRIPTION("Crypto hardware engine framework");