diff options
| -rw-r--r-- | crypto/Kconfig | 3 | ||||
| -rw-r--r-- | crypto/Makefile | 1 | ||||
| -rw-r--r-- | crypto/crypto_engine.c | 355 | ||||
| -rw-r--r-- | include/crypto/algapi.h | 70 |
4 files changed, 429 insertions, 0 deletions
diff --git a/crypto/Kconfig b/crypto/Kconfig index 099f1f1b0857..f6bfdda1a0b9 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -217,6 +217,9 @@ config CRYPTO_GLUE_HELPER_X86 depends on X86 select CRYPTO_ALGAPI +config CRYPTO_ENGINE + tristate + comment "Authenticated Encryption with Associated Data" config CRYPTO_CCM diff --git a/crypto/Makefile b/crypto/Makefile index 059de1bb254b..4f4ef7eaae3f 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -7,6 +7,7 @@ crypto-y := api.o cipher.o compress.o memneq.o obj-$(CONFIG_CRYPTO_WORKQUEUE) += crypto_wq.o +obj-$(CONFIG_CRYPTO_ENGINE) += crypto_engine.o obj-$(CONFIG_CRYPTO_FIPS) += fips.o crypto_algapi-$(CONFIG_PROC_FS) += proc.o diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c new file mode 100644 index 000000000000..a55c82dd48ef --- /dev/null +++ b/crypto/crypto_engine.c @@ -0,0 +1,355 @@ +/* + * Handle async block request by crypto hardware engine. + * + * Copyright (C) 2016 Linaro, Inc. + * + * Author: Baolin Wang <baolin.wang@linaro.org> + * + * 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. + * + */ + +#include <linux/err.h> +#include <linux/delay.h> +#include "internal.h" + +#define CRYPTO_ENGINE_MAX_QLEN 10 + +void crypto_finalize_request(struct crypto_engine *engine, + struct ablkcipher_request *req, int err); + +/** + * crypto_pump_requests - dequeue one request from engine queue to process + * @engine: the hardware engine + * @in_kthread: true if we are in the context of the request pump thread + * + * This function checks if there is any request in the engine queue that + * needs processing and if so call out to the driver to initialize hardware + * and handle each request. + */ +static void crypto_pump_requests(struct crypto_engine *engine, + bool in_kthread) +{ + struct crypto_async_request *async_req, *backlog; + struct ablkcipher_request *req; + unsigned long flags; + bool was_busy = false; + int ret; + + spin_lock_irqsave(&engine->queue_lock, flags); + + /* Make sure we are not already running a request */ + if (engine->cur_req) + goto out; + + /* If another context is idling then defer */ + if (engine->idling) { + queue_kthread_work(&engine->kworker, &engine->pump_requests); + goto out; + } + + /* Check if the engine queue is idle */ + if (!crypto_queue_len(&engine->queue) || !engine->running) { + if (!engine->busy) + goto out; + + /* Only do teardown in the thread */ + if (!in_kthread) { + queue_kthread_work(&engine->kworker, + &engine->pump_requests); + goto out; + } + + engine->busy = false; + engine->idling = true; + spin_unlock_irqrestore(&engine->queue_lock, flags); + + if (engine->unprepare_crypt_hardware && + engine->unprepare_crypt_hardware(engine)) + pr_err("failed to unprepare crypt hardware\n"); + + spin_lock_irqsave(&engine->queue_lock, flags); + engine->idling = false; + goto out; + } + + /* Get the fist request from the engine queue to handle */ + backlog = crypto_get_backlog(&engine->queue); + async_req = crypto_dequeue_request(&engine->queue); + if (!async_req) + goto out; + + req = ablkcipher_request_cast(async_req); + + engine->cur_req = req; + if (backlog) + backlog->complete(backlog, -EINPROGRESS); + + if (engine->busy) + was_busy = true; + else + engine->busy = true; + + spin_unlock_irqrestore(&engine->queue_lock, flags); + + /* Until here we get the request need to be encrypted successfully */ + if (!was_busy && engine->prepare_crypt_hardware) { + ret = engine->prepare_crypt_hardware(engine); + if (ret) { + pr_err("failed to prepare crypt hardware\n"); + goto req_err; + } + } + + if (engine->prepare_request) { + ret = engine->prepare_request(engine, engine->cur_req); + if (ret) { + pr_err("failed to prepare request: %d\n", ret); + goto req_err; + } + engine->cur_req_prepared = true; + } + + ret = engine->crypt_one_request(engine, engine->cur_req); + if (ret) { + pr_err("failed to crypt one request from queue\n"); + goto req_err; + } + return; + +req_err: + crypto_finalize_request(engine, engine->cur_req, ret); + return; + +out: + spin_unlock_irqrestore(&engine->queue_lock, flags); +} + +static void crypto_pump_work(struct kthread_work *work) +{ + struct crypto_engine *engine = + container_of(work, struct crypto_engine, pump_requests); + + crypto_pump_requests(engine, true); +} + +/** + * crypto_transfer_request - transfer the new request into the engine queue + * @engine: the hardware engine + * @req: the request need to be listed into the engine queue + */ +int crypto_transfer_request(struct crypto_engine *engine, + struct ablkcipher_request *req, bool need_pump) +{ + unsigned long flags; + int ret; + + spin_lock_irqsave(&engine->queue_lock, flags); + + if (!engine->running) { + spin_unlock_irqrestore(&engine->queue_lock, flags); + return -ESHUTDOWN; + } + + ret = ablkcipher_enqueue_request(&engine->queue, req); + + if (!engine->busy && need_pump) + queue_kthread_work(&engine->kworker, &engine->pump_requests); + + spin_unlock_irqrestore(&engine->queue_lock, flags); + return ret; +} +EXPORT_SYMBOL_GPL(crypto_transfer_request); + +/** + * crypto_transfer_request_to_engine - transfer one request to list into the + * engine queue + * @engine: the hardware engine + * @req: the request need to be listed into the engine queue + */ +int crypto_transfer_request_to_engine(struct crypto_engine *engine, + struct ablkcipher_request *req) +{ + return crypto_transfer_request(engine, req, true); +} +EXPORT_SYMBOL_GPL(crypto_transfer_request_to_engine); + +/** + * crypto_finalize_request - finalize one request if the request is done + * @engine: the hardware engine + * @req: the request need to be finalized + * @err: error number + */ +void crypto_finalize_request(struct crypto_engine *engine, + struct ablkcipher_request *req, int err) +{ + unsigned long flags; + bool finalize_cur_req = false; + int ret; + + spin_lock_irqsave(&engine->queue_lock, flags); + if (engine->cur_req == req) + finalize_cur_req = true; + spin_unlock_irqrestore(&engine->queue_lock, flags); + + if (finalize_cur_req) { + if (engine->cur_req_prepared && engine->unprepare_request) { + ret = engine->unprepare_request(engine, req); + if (ret) + pr_err("failed to unprepare request\n"); + } + + spin_lock_irqsave(&engine->queue_lock, flags); + engine->cur_req = NULL; + engine->cur_req_prepared = false; + spin_unlock_irqrestore(&engine->queue_lock, flags); + } + + req->base.complete(&req->base, err); + + queue_kthread_work(&engine->kworker, &engine->pump_requests); +} +EXPORT_SYMBOL_GPL(crypto_finalize_request); + +/** + * crypto_engine_start - start the hardware engine + * @engine: the hardware engine need to be started + * + * Return 0 on success, else on fail. + */ +int crypto_engine_start(struct crypto_engine *engine) +{ + unsigned long flags; + + spin_lock_irqsave(&engine->queue_lock, flags); + + if (engine->running || engine->busy) { + spin_unlock_irqrestore(&engine->queue_lock, flags); + return -EBUSY; + } + + engine->running = true; + spin_unlock_irqrestore(&engine->queue_lock, flags); + + queue_kthread_work(&engine->kworker, &engine->pump_requests); + + return 0; +} +EXPORT_SYMBOL_GPL(crypto_engine_start); + +/** + * crypto_engine_stop - stop the hardware engine + * @engine: the hardware engine need to be stopped + * + * Return 0 on success, else on fail. + */ +int crypto_engine_stop(struct crypto_engine *engine) +{ + unsigned long flags; + unsigned limit = 500; + int ret = 0; + + spin_lock_irqsave(&engine->queue_lock, flags); + + /* + * If the engine queue is not empty or the engine is on busy state, + * we need to wait for a while to pump the requests of engine queue. + */ + while ((crypto_queue_len(&engine->queue) || engine->busy) && limit--) { + spin_unlock_irqrestore(&engine->queue_lock, flags); + msleep(20); + spin_lock_irqsave(&engine->queue_lock, flags); + } + + if (crypto_queue_len(&engine->queue) || engine->busy) + ret = -EBUSY; + else + engine->running = false; + + spin_unlock_irqrestore(&engine->queue_lock, flags); + + if (ret) + pr_warn("could not stop engine\n"); + + return ret; +} +EXPORT_SYMBOL_GPL(crypto_engine_stop); + +/** + * crypto_engine_alloc_init - allocate crypto hardware engine structure and + * initialize it. + * @dev: the device attached with one hardware engine + * @rt: whether this queue is set to run as a realtime task + * + * This must be called from context that can sleep. + * Return: the crypto engine structure on success, else NULL. + */ +struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt) +{ + struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 }; + struct crypto_engine *engine; + + if (!dev) + return NULL; + + engine = devm_kzalloc(dev, sizeof(*engine), GFP_KERNEL); + if (!engine) + return NULL; + + engine->rt = rt; + engine->running = false; + engine->busy = false; + engine->idling = false; + engine->cur_req_prepared = false; + engine->priv_data = dev; + snprintf(engine->name, sizeof(engine->name), + "%s-engine", dev_name(dev)); + + crypto_init_queue(&engine->queue, CRYPTO_ENGINE_MAX_QLEN); + spin_lock_init(&engine->queue_lock); + + init_kthread_worker(&engine->kworker); + engine->kworker_task = kthread_run(kthread_worker_fn, + &engine->kworker, "%s", + engine->name); + if (IS_ERR(engine->kworker_task)) { + dev_err(dev, "failed to create crypto request pump task\n"); + return NULL; + } + init_kthread_work(&engine->pump_requests, crypto_pump_work); + + if (engine->rt) { + dev_info(dev, "will run requests pump with realtime priority\n"); + sched_setscheduler(engine->kworker_task, SCHED_FIFO, ¶m); + } + + return engine; +} +EXPORT_SYMBOL_GPL(crypto_engine_alloc_init); + +/** + * crypto_engine_exit - free the resources of hardware engine when exit + * @engine: the hardware engine need to be freed + * + * Return 0 for success. + */ +int crypto_engine_exit(struct crypto_engine *engine) +{ + int ret; + + ret = crypto_engine_stop(engine); + if (ret) + return ret; + + flush_kthread_worker(&engine->kworker); + kthread_stop(engine->kworker_task); + + return 0; +} +EXPORT_SYMBOL_GPL(crypto_engine_exit); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Crypto hardware engine framework"); diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h index 4f861c44d066..b09d43f612e1 100644 --- a/include/crypto/algapi.h +++ b/include/crypto/algapi.h @@ -15,6 +15,7 @@ #include <linux/crypto.h> #include <linux/list.h> #include <linux/kernel.h> +#include <linux/kthread.h> #include <linux/skbuff.h> struct crypto_aead; @@ -128,6 +129,75 @@ struct ablkcipher_walk { unsigned int blocksize; }; +#define ENGINE_NAME_LEN 30 +/* + * struct crypto_engine - crypto hardware engine + * @name: the engine name + * @idling: the engine is entering idle state + * @busy: request pump is busy + * @running: the engine is on working + * @cur_req_prepared: current request is prepared + * @list: link with the global crypto engine list + * @queue_lock: spinlock to syncronise access to request queue + * @queue: the crypto queue of the engine + * @rt: whether this queue is set to run as a realtime task + * @prepare_crypt_hardware: a request will soon arrive from the queue + * so the subsystem requests the driver to prepare the hardware + * by issuing this call + * @unprepare_crypt_hardware: there are currently no more requests on the + * queue so the subsystem notifies the driver that it may relax the + * hardware by issuing this call + * @prepare_request: do some prepare if need before handle the current request + * @unprepare_request: undo any work done by prepare_message() + * @crypt_one_request: do encryption for current request + * @kworker: thread struct for request pump + * @kworker_task: pointer to task for request pump kworker thread + * @pump_requests: work struct for scheduling work to the request pump + * @priv_data: the engine private data + * @cur_req: the current request which is on processing + */ +struct crypto_engine { + char name[ENGINE_NAME_LEN]; + bool idling; + bool busy; + bool running; + bool cur_req_prepared; + + struct list_head list; + spinlock_t queue_lock; + struct crypto_queue queue; + + bool rt; + + int (*prepare_crypt_hardware)(struct crypto_engine *engine); + int (*unprepare_crypt_hardware)(struct crypto_engine *engine); + + int (*prepare_request)(struct crypto_engine *engine, + struct ablkcipher_request *req); + int (*unprepare_request)(struct crypto_engine *engine, + struct ablkcipher_request *req); + int (*crypt_one_request)(struct crypto_engine *engine, + struct ablkcipher_request *req); + + struct kthread_worker kworker; + struct task_struct *kworker_task; + struct kthread_work pump_requests; + + void *priv_data; + struct ablkcipher_request *cur_req; +}; + +int crypto_transfer_request(struct crypto_engine *engine, + struct ablkcipher_request *req, bool need_pump); +int crypto_transfer_request_to_engine(struct crypto_engine *engine, + struct ablkcipher_request *req); +void crypto_finalize_request(struct crypto_engine *engine, + struct ablkcipher_request *req, int err); +int crypto_engine_start(struct crypto_engine *engine); +int crypto_engine_stop(struct crypto_engine *engine); +struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt); +int crypto_engine_exit(struct crypto_engine *engine); + extern const struct crypto_type crypto_ablkcipher_type; extern const struct crypto_type crypto_blkcipher_type; |