linux/crypto/crypto_engine.c

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/*
* 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 <crypto/engine.h>
#include <uapi/linux/sched/types.h>
#include "internal.h"
#define CRYPTO_ENGINE_MAX_QLEN 10
/**
* 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
*/
static void crypto_finalize_request(struct crypto_engine *engine,
struct crypto_async_request *req, int err)
{
unsigned long flags;
bool finalize_cur_req = false;
int ret;
struct crypto_engine_ctx *enginectx;
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) {
enginectx = crypto_tfm_ctx(req->tfm);
if (engine->cur_req_prepared &&
enginectx->op.unprepare_request) {
ret = enginectx->op.unprepare_request(engine, req);
if (ret)
dev_err(engine->dev, "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->complete(req, err);
kthread_queue_work(engine->kworker, &engine->pump_requests);
}
/**
* 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;
unsigned long flags;
bool was_busy = false;
int ret;
struct crypto_engine_ctx *enginectx;
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) {
kthread_queue_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) {
kthread_queue_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))
dev_err(engine->dev, "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;
engine->cur_req = async_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) {
dev_err(engine->dev, "failed to prepare crypt hardware\n");
goto req_err;
}
}
enginectx = crypto_tfm_ctx(async_req->tfm);
if (enginectx->op.prepare_request) {
ret = enginectx->op.prepare_request(engine, async_req);
if (ret) {
dev_err(engine->dev, "failed to prepare request: %d\n",
ret);
goto req_err;
}
engine->cur_req_prepared = true;
}
if (!enginectx->op.do_one_request) {
dev_err(engine->dev, "failed to do request\n");
ret = -EINVAL;
goto req_err;
}
ret = enginectx->op.do_one_request(engine, async_req);
if (ret) {
dev_err(engine->dev, "Failed to do one request from queue: %d\n", ret);
goto req_err;
}
return;
req_err:
crypto_finalize_request(engine, async_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
*/
static int crypto_transfer_request(struct crypto_engine *engine,
struct crypto_async_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 = crypto_enqueue_request(&engine->queue, req);
if (!engine->busy && need_pump)
kthread_queue_work(engine->kworker, &engine->pump_requests);
spin_unlock_irqrestore(&engine->queue_lock, flags);
return ret;
}
/**
* 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
*/
static int crypto_transfer_request_to_engine(struct crypto_engine *engine,
struct crypto_async_request *req)
{
return crypto_transfer_request(engine, req, true);
}
/**
* crypto_transfer_ablkcipher_request_to_engine - transfer one ablkcipher_request
* to list into the engine queue
* @engine: the hardware engine
* @req: the request need to be listed into the engine queue
* TODO: Remove this function when skcipher conversion is finished
*/
int crypto_transfer_ablkcipher_request_to_engine(struct crypto_engine *engine,
struct ablkcipher_request *req)
{
return crypto_transfer_request_to_engine(engine, &req->base);
}
EXPORT_SYMBOL_GPL(crypto_transfer_ablkcipher_request_to_engine);
/**
* crypto_transfer_aead_request_to_engine - transfer one aead_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_aead_request_to_engine(struct crypto_engine *engine,
struct aead_request *req)
{
return crypto_transfer_request_to_engine(engine, &req->base);
}
EXPORT_SYMBOL_GPL(crypto_transfer_aead_request_to_engine);
/**
* crypto_transfer_akcipher_request_to_engine - transfer one akcipher_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_akcipher_request_to_engine(struct crypto_engine *engine,
struct akcipher_request *req)
{
return crypto_transfer_request_to_engine(engine, &req->base);
}
EXPORT_SYMBOL_GPL(crypto_transfer_akcipher_request_to_engine);
/**
* crypto_transfer_hash_request_to_engine - transfer one ahash_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_hash_request_to_engine(struct crypto_engine *engine,
struct ahash_request *req)
{
return crypto_transfer_request_to_engine(engine, &req->base);
}
EXPORT_SYMBOL_GPL(crypto_transfer_hash_request_to_engine);
/**
* crypto_transfer_skcipher_request_to_engine - transfer one skcipher_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_skcipher_request_to_engine(struct crypto_engine *engine,
struct skcipher_request *req)
{
return crypto_transfer_request_to_engine(engine, &req->base);
}
EXPORT_SYMBOL_GPL(crypto_transfer_skcipher_request_to_engine);
/**
* crypto_finalize_ablkcipher_request - finalize one ablkcipher_request if
* the request is done
* @engine: the hardware engine
* @req: the request need to be finalized
* @err: error number
* TODO: Remove this function when skcipher conversion is finished
*/
void crypto_finalize_ablkcipher_request(struct crypto_engine *engine,
struct ablkcipher_request *req, int err)
{
return crypto_finalize_request(engine, &req->base, err);
}
EXPORT_SYMBOL_GPL(crypto_finalize_ablkcipher_request);
/**
* crypto_finalize_aead_request - finalize one aead_request if
* the request is done
* @engine: the hardware engine
* @req: the request need to be finalized
* @err: error number
*/
void crypto_finalize_aead_request(struct crypto_engine *engine,
struct aead_request *req, int err)
{
return crypto_finalize_request(engine, &req->base, err);
}
EXPORT_SYMBOL_GPL(crypto_finalize_aead_request);
/**
* crypto_finalize_akcipher_request - finalize one akcipher_request if
* the request is done
* @engine: the hardware engine
* @req: the request need to be finalized
* @err: error number
*/
void crypto_finalize_akcipher_request(struct crypto_engine *engine,
struct akcipher_request *req, int err)
{
return crypto_finalize_request(engine, &req->base, err);
}
EXPORT_SYMBOL_GPL(crypto_finalize_akcipher_request);
/**
* crypto_finalize_hash_request - finalize one ahash_request if
* the request is done
* @engine: the hardware engine
* @req: the request need to be finalized
* @err: error number
*/
void crypto_finalize_hash_request(struct crypto_engine *engine,
struct ahash_request *req, int err)
{
return crypto_finalize_request(engine, &req->base, err);
}
EXPORT_SYMBOL_GPL(crypto_finalize_hash_request);
/**
* crypto_finalize_skcipher_request - finalize one skcipher_request if
* the request is done
* @engine: the hardware engine
* @req: the request need to be finalized
* @err: error number
*/
void crypto_finalize_skcipher_request(struct crypto_engine *engine,
struct skcipher_request *req, int err)
{
return crypto_finalize_request(engine, &req->base, err);
}
EXPORT_SYMBOL_GPL(crypto_finalize_skcipher_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);
kthread_queue_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 int 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)
dev_warn(engine->dev, "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->dev = dev;
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);
engine->kworker = kthread_create_worker(0, "%s", engine->name);
if (IS_ERR(engine->kworker)) {
dev_err(dev, "failed to create crypto request pump task\n");
return NULL;
}
kthread: kthread worker API cleanup A good practice is to prefix the names of functions by the name of the subsystem. The kthread worker API is a mix of classic kthreads and workqueues. Each worker has a dedicated kthread. It runs a generic function that process queued works. It is implemented as part of the kthread subsystem. This patch renames the existing kthread worker API to use the corresponding name from the workqueues API prefixed by kthread_: __init_kthread_worker() -> __kthread_init_worker() init_kthread_worker() -> kthread_init_worker() init_kthread_work() -> kthread_init_work() insert_kthread_work() -> kthread_insert_work() queue_kthread_work() -> kthread_queue_work() flush_kthread_work() -> kthread_flush_work() flush_kthread_worker() -> kthread_flush_worker() Note that the names of DEFINE_KTHREAD_WORK*() macros stay as they are. It is common that the "DEFINE_" prefix has precedence over the subsystem names. Note that INIT() macros and init() functions use different naming scheme. There is no good solution. There are several reasons for this solution: + "init" in the function names stands for the verb "initialize" aka "initialize worker". While "INIT" in the macro names stands for the noun "INITIALIZER" aka "worker initializer". + INIT() macros are used only in DEFINE() macros + init() functions are used close to the other kthread() functions. It looks much better if all the functions use the same scheme. + There will be also kthread_destroy_worker() that will be used close to kthread_cancel_work(). It is related to the init() function. Again it looks better if all functions use the same naming scheme. + there are several precedents for such init() function names, e.g. amd_iommu_init_device(), free_area_init_node(), jump_label_init_type(), regmap_init_mmio_clk(), + It is not an argument but it was inconsistent even before. [arnd@arndb.de: fix linux-next merge conflict] Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com Suggested-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Petr Mladek <pmladek@suse.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Cc: Josh Triplett <josh@joshtriplett.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jiri Kosina <jkosina@suse.cz> Cc: Borislav Petkov <bp@suse.de> Cc: Michal Hocko <mhocko@suse.cz> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-10-11 22:55:20 +02:00
kthread_init_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, &param);
}
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;
kthread_destroy_worker(engine->kworker);
return 0;
}
EXPORT_SYMBOL_GPL(crypto_engine_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Crypto hardware engine framework");