2020-02-04 12:35:05

by Iuliana Prodan

[permalink] [raw]
Subject: [PATCH v2 0/2] crypto: engine - support for parallel and batch requests

Added support for executing multiple, independent or not, requests
for crypto engine. This is based on a callback, can_enqueue_more, which
asks the driver if the hardware has free space, to enqueue a new request.
If hardware supports batch requests, crypto-engine can handle this use-case
through do_batch_requests callback.

Since, these new features, cannot be supported by all hardware,
the crypto-engine framework is backward compatible:
- by using the crypto_engine_alloc_init function, to initialize
crypto-engine, the new callbacks are NULL and the engine will work
as before these changes;
- to support only multiple requests, in parallel, the can_enqueue_more
callback must be implemented in driver. On crypto_pump_requests, if
can_enqueue_more callback returns true, a new request is send
to hardware, until there is no space and the callback returns false.
- to support batch requests, do_batch_requests callback must be
implemented in driver, to execute a batch of requests. The link
between the requests, is expected to be done in driver, in do_one_request().

Signed-off-by: Iuliana Prodan <[email protected]>

---
Changes since V1:
- changed the name of can_enqueue_hardware callback to can_enqueue_more, and
the argument of this callback to crypto_engine structure (for cases when more
than ore crypto-engine is used).
- added a new patch with support for batch requests.

Changes since V0 (RFC):
- removed max_no_req and no_req, as the number of request that can be
processed in parallel;
- added a new callback, can_enqueue_more, to check whether the hardware
can process a new request.


Iuliana Prodan (2):
crypto: engine - support for parallel requests
crypto: engine - support for batch requests

crypto/crypto_engine.c | 121 ++++++++++++++++++++++++++++++++----------------
include/crypto/engine.h | 13 ++++--
2 files changed, 90 insertions(+), 44 deletions(-)

--
2.1.0


2020-02-04 12:35:29

by Iuliana Prodan

[permalink] [raw]
Subject: [PATCH v2 2/2] crypto: engine - support for batch requests

Added support for batch requests, per crypto engine.
A new callback is added, do_batch_requests, which executes a
batch of requests. This has the crypto_engine structure as argument
(for cases when more than one crypto-engine is used).
The crypto_engine_alloc_init_and_set function, initializes
crypto-engine, and also, sets the do_batch_requests callback.
On crypto_pump_requests, if do_batch_requests callback is
implemented in a driver, this will be executed. The link between
the requests will be done in driver, in do_one_request().

Signed-off-by: Iuliana Prodan <[email protected]>
---
crypto/crypto_engine.c | 17 ++++++++++++++++-
include/crypto/engine.h | 3 +++
2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
index aba934f..378772e 100644
--- a/crypto/crypto_engine.c
+++ b/crypto/crypto_engine.c
@@ -162,6 +162,12 @@ static void crypto_pump_requests(struct crypto_engine *engine,
return;
out:
spin_unlock_irqrestore(&engine->queue_lock, flags);
+ if (engine->do_batch_requests) {
+ ret = engine->do_batch_requests(engine);
+ if (ret)
+ dev_err(engine->dev, "failed to do batch requests: %d\n",
+ ret);
+ }
}

static void crypto_pump_work(struct kthread_work *work)
@@ -396,6 +402,12 @@ EXPORT_SYMBOL_GPL(crypto_engine_stop);
* callback(struct crypto_engine *engine)
* where:
* @engine: the crypto engine structure.
+ * @cbk_do_batch: pointer to a callback function to be invoked when executing a
+ * a batch of requests.
+ * This has the form:
+ * callback(struct crypto_engine *engine)
+ * where:
+ * @engine: the crypto engine structure.
* @rt: whether this queue is set to run as a realtime task
* @qlen: maximum size of the crypto-engine queue
*
@@ -404,6 +416,7 @@ EXPORT_SYMBOL_GPL(crypto_engine_stop);
*/
struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
bool (*cbk_can_enq)(struct crypto_engine *engine),
+ int (*cbk_do_batch)(struct crypto_engine *engine),
bool rt, int qlen)
{
struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
@@ -423,6 +436,8 @@ struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
engine->idling = false;
engine->priv_data = dev;
engine->can_enqueue_more = cbk_can_enq;
+ engine->do_batch_requests = cbk_do_batch;
+
snprintf(engine->name, sizeof(engine->name),
"%s-engine", dev_name(dev));

@@ -456,7 +471,7 @@ EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
*/
struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
{
- return crypto_engine_alloc_init_and_set(dev, NULL, rt,
+ return crypto_engine_alloc_init_and_set(dev, NULL, NULL, rt,
CRYPTO_ENGINE_MAX_QLEN);
}
EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);
diff --git a/include/crypto/engine.h b/include/crypto/engine.h
index 07c3f80..27cddc4 100644
--- a/include/crypto/engine.h
+++ b/include/crypto/engine.h
@@ -34,6 +34,7 @@
* @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
+ * @do_batch_requests: execute a batch of requests
* @can_enqueue_more: callback to check whether the hardware can process
* a new request
* @kworker: kthread worker struct for request pump
@@ -55,6 +56,7 @@ struct crypto_engine {

int (*prepare_crypt_hardware)(struct crypto_engine *engine);
int (*unprepare_crypt_hardware)(struct crypto_engine *engine);
+ int (*do_batch_requests)(struct crypto_engine *engine);
bool (*can_enqueue_more)(struct crypto_engine *engine);

struct kthread_worker *kworker;
@@ -103,6 +105,7 @@ int crypto_engine_stop(struct crypto_engine *engine);
struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt);
struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
bool (*cbk_can_enq)(struct crypto_engine *engine),
+ int (*cbk_do_batch)(struct crypto_engine *engine),
bool rt, int qlen);
int crypto_engine_exit(struct crypto_engine *engine);

--
2.1.0

2020-02-04 12:35:33

by Iuliana Prodan

[permalink] [raw]
Subject: [PATCH v2 1/2] crypto: engine - support for parallel requests

Added support for executing multiple requests, in parallel,
for crypto engine.
A new callback is added, can_enqueue_more, which asks the
driver if the hardware has free space, to enqueue a new request.
The new crypto_engine_alloc_init_and_set function, initialize
crypto-engine, sets the maximum size for crypto-engine software
queue (not hardcoded anymore) and the can_enqueue_more callback.
On crypto_pump_requests, if can_enqueue_more callback returns true,
a new request is send to hardware, until there is no space and the
callback returns false.

Signed-off-by: Iuliana Prodan <[email protected]>
---
crypto/crypto_engine.c | 106 ++++++++++++++++++++++++++++++------------------
include/crypto/engine.h | 10 +++--
2 files changed, 72 insertions(+), 44 deletions(-)

diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
index eb029ff..aba934f 100644
--- a/crypto/crypto_engine.c
+++ b/crypto/crypto_engine.c
@@ -22,32 +22,18 @@
* @err: error number
*/
static void crypto_finalize_request(struct crypto_engine *engine,
- struct crypto_async_request *req, int err)
+ 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);
+ enginectx = crypto_tfm_ctx(req->tfm);
+ if (enginectx->op.prepare_request &&
+ enginectx->op.unprepare_request) {
+ ret = enginectx->op.unprepare_request(engine, req);
+ if (ret)
+ dev_err(engine->dev, "failed to unprepare request\n");
}
-
req->complete(req, err);

kthread_queue_work(engine->kworker, &engine->pump_requests);
@@ -73,10 +59,6 @@ static void crypto_pump_requests(struct crypto_engine *engine,

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);
@@ -108,13 +90,18 @@ static void crypto_pump_requests(struct crypto_engine *engine,
goto out;
}

+start_request:
+ /* If hw is busy, do not send any request */
+ if (engine->can_enqueue_more &&
+ !engine->can_enqueue_more(engine))
+ 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);

@@ -130,7 +117,7 @@ static void crypto_pump_requests(struct crypto_engine *engine,
ret = engine->prepare_crypt_hardware(engine);
if (ret) {
dev_err(engine->dev, "failed to prepare crypt hardware\n");
- goto req_err;
+ goto req_err_2;
}
}

@@ -141,26 +128,38 @@ static void crypto_pump_requests(struct crypto_engine *engine,
if (ret) {
dev_err(engine->dev, "failed to prepare request: %d\n",
ret);
- goto req_err;
+ goto req_err_2;
}
- 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;
+ goto req_err_1;
}
+
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;
+ goto req_err_1;
}
- return;

-req_err:
- crypto_finalize_request(engine, async_req, ret);
- return;
+ goto retry;
+
+req_err_1:
+ if (enginectx->op.unprepare_request) {
+ ret = enginectx->op.unprepare_request(engine, async_req);
+ if (ret)
+ dev_err(engine->dev, "failed to unprepare request\n");
+ }
+req_err_2:
+ async_req->complete(async_req, ret);

+retry:
+ if (engine->can_enqueue_more) {
+ spin_lock_irqsave(&engine->queue_lock, flags);
+ goto start_request;
+ }
+ return;
out:
spin_unlock_irqrestore(&engine->queue_lock, flags);
}
@@ -386,15 +385,26 @@ int crypto_engine_stop(struct crypto_engine *engine)
EXPORT_SYMBOL_GPL(crypto_engine_stop);

/**
- * crypto_engine_alloc_init - allocate crypto hardware engine structure and
- * initialize it.
+ * crypto_engine_alloc_init_and_set - allocate crypto hardware engine structure
+ * and initialize it by setting the maximum number of entries in the software
+ * crypto-engine queue.
* @dev: the device attached with one hardware engine
+ * @cbk_can_enq: pointer to a callback function to be invoked when pumping
+ * requests to check whether the hardware can process a new
+ * request.
+ * This has the form:
+ * callback(struct crypto_engine *engine)
+ * where:
+ * @engine: the crypto engine structure.
* @rt: whether this queue is set to run as a realtime task
+ * @qlen: maximum size of the crypto-engine queue
*
* 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 crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
+ bool (*cbk_can_enq)(struct crypto_engine *engine),
+ bool rt, int qlen)
{
struct sched_param param = { .sched_priority = MAX_RT_PRIO / 2 };
struct crypto_engine *engine;
@@ -411,12 +421,12 @@ struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)
engine->running = false;
engine->busy = false;
engine->idling = false;
- engine->cur_req_prepared = false;
engine->priv_data = dev;
+ engine->can_enqueue_more = cbk_can_enq;
snprintf(engine->name, sizeof(engine->name),
"%s-engine", dev_name(dev));

- crypto_init_queue(&engine->queue, CRYPTO_ENGINE_MAX_QLEN);
+ crypto_init_queue(&engine->queue, qlen);
spin_lock_init(&engine->queue_lock);

engine->kworker = kthread_create_worker(0, "%s", engine->name);
@@ -433,6 +443,22 @@ struct crypto_engine *crypto_engine_alloc_init(struct device *dev, bool rt)

return engine;
}
+EXPORT_SYMBOL_GPL(crypto_engine_alloc_init_and_set);
+
+/**
+ * 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)
+{
+ return crypto_engine_alloc_init_and_set(dev, NULL, rt,
+ CRYPTO_ENGINE_MAX_QLEN);
+}
EXPORT_SYMBOL_GPL(crypto_engine_alloc_init);

/**
diff --git a/include/crypto/engine.h b/include/crypto/engine.h
index e29cd67..07c3f80 100644
--- a/include/crypto/engine.h
+++ b/include/crypto/engine.h
@@ -24,7 +24,6 @@
* @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
@@ -35,17 +34,17 @@
* @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
+ * @can_enqueue_more: callback to check whether the hardware can process
+ * a new request
* @kworker: kthread worker struct for request pump
* @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;
@@ -56,12 +55,12 @@ struct crypto_engine {

int (*prepare_crypt_hardware)(struct crypto_engine *engine);
int (*unprepare_crypt_hardware)(struct crypto_engine *engine);
+ bool (*can_enqueue_more)(struct crypto_engine *engine);

struct kthread_worker *kworker;
struct kthread_work pump_requests;

void *priv_data;
- struct crypto_async_request *cur_req;
};

/*
@@ -102,6 +101,9 @@ void crypto_finalize_skcipher_request(struct crypto_engine *engine,
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);
+struct crypto_engine *crypto_engine_alloc_init_and_set(struct device *dev,
+ bool (*cbk_can_enq)(struct crypto_engine *engine),
+ bool rt, int qlen);
int crypto_engine_exit(struct crypto_engine *engine);

#endif /* _CRYPTO_ENGINE_H */
--
2.1.0

2020-02-05 19:11:59

by Corentin Labbe

[permalink] [raw]
Subject: Re: [PATCH v2 1/2] crypto: engine - support for parallel requests

On Tue, Feb 04, 2020 at 02:34:19PM +0200, Iuliana Prodan wrote:
> Added support for executing multiple requests, in parallel,
> for crypto engine.
> A new callback is added, can_enqueue_more, which asks the
> driver if the hardware has free space, to enqueue a new request.
> The new crypto_engine_alloc_init_and_set function, initialize
> crypto-engine, sets the maximum size for crypto-engine software
> queue (not hardcoded anymore) and the can_enqueue_more callback.
> On crypto_pump_requests, if can_enqueue_more callback returns true,
> a new request is send to hardware, until there is no space and the
> callback returns false.
>
> Signed-off-by: Iuliana Prodan <[email protected]>
> ---
> crypto/crypto_engine.c | 106 ++++++++++++++++++++++++++++++------------------
> include/crypto/engine.h | 10 +++--
> 2 files changed, 72 insertions(+), 44 deletions(-)
>
> diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
> index eb029ff..aba934f 100644
> --- a/crypto/crypto_engine.c
> +++ b/crypto/crypto_engine.c
> @@ -22,32 +22,18 @@
> * @err: error number
> */
> static void crypto_finalize_request(struct crypto_engine *engine,
> - struct crypto_async_request *req, int err)
> + 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);
> + enginectx = crypto_tfm_ctx(req->tfm);
> + if (enginectx->op.prepare_request &&
> + enginectx->op.unprepare_request) {
> + ret = enginectx->op.unprepare_request(engine, req);
> + if (ret)
> + dev_err(engine->dev, "failed to unprepare request\n");
> }
> -
> req->complete(req, err);
>
> kthread_queue_work(engine->kworker, &engine->pump_requests);
> @@ -73,10 +59,6 @@ static void crypto_pump_requests(struct crypto_engine *engine,
>
> spin_lock_irqsave(&engine->queue_lock, flags);
>
> - /* Make sure we are not already running a request */
> - if (engine->cur_req)
> - goto out;
> -

Hello

Your patch has the same problem than mine reported by Horia.
If a queue has more than one request, a first crypto_pump_requests() will send a request and for drivers which do not block on do_one_request() crypto_pump_requests() will end.
Then another crypto_pump_requests() will fire sending a second request while the driver does not support that.

So we need to replace engine->cur_req by another locking mechanism.
Perhaps the cleaner is to add a "request count" (increased when do_one_request, decreased in crypto_finalize_request)
I know that the early version have that and it was removed, but I do not see any better way.

Regards

2020-02-07 11:27:10

by Iuliana Prodan

[permalink] [raw]
Subject: Re: [PATCH v2 1/2] crypto: engine - support for parallel requests

On 2/5/2020 9:11 PM, Corentin Labbe wrote:
> On Tue, Feb 04, 2020 at 02:34:19PM +0200, Iuliana Prodan wrote:
>> Added support for executing multiple requests, in parallel,
>> for crypto engine.
>> A new callback is added, can_enqueue_more, which asks the
>> driver if the hardware has free space, to enqueue a new request.
>> The new crypto_engine_alloc_init_and_set function, initialize
>> crypto-engine, sets the maximum size for crypto-engine software
>> queue (not hardcoded anymore) and the can_enqueue_more callback.
>> On crypto_pump_requests, if can_enqueue_more callback returns true,
>> a new request is send to hardware, until there is no space and the
>> callback returns false.
>>
>> Signed-off-by: Iuliana Prodan <[email protected]>
>> ---
>> crypto/crypto_engine.c | 106 ++++++++++++++++++++++++++++++------------------
>> include/crypto/engine.h | 10 +++--
>> 2 files changed, 72 insertions(+), 44 deletions(-)
>>
>> diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
>> index eb029ff..aba934f 100644
>> --- a/crypto/crypto_engine.c
>> +++ b/crypto/crypto_engine.c
>> @@ -22,32 +22,18 @@
>> * @err: error number
>> */
>> static void crypto_finalize_request(struct crypto_engine *engine,
>> - struct crypto_async_request *req, int err)
>> + 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);
>> + enginectx = crypto_tfm_ctx(req->tfm);
>> + if (enginectx->op.prepare_request &&
>> + enginectx->op.unprepare_request) {
>> + ret = enginectx->op.unprepare_request(engine, req);
>> + if (ret)
>> + dev_err(engine->dev, "failed to unprepare request\n");
>> }
>> -
>> req->complete(req, err);
>>
>> kthread_queue_work(engine->kworker, &engine->pump_requests);
>> @@ -73,10 +59,6 @@ static void crypto_pump_requests(struct crypto_engine *engine,
>>
>> spin_lock_irqsave(&engine->queue_lock, flags);
>>
>> - /* Make sure we are not already running a request */
>> - if (engine->cur_req)
>> - goto out;
>> -
>
> Hello
>
> Your patch has the same problem than mine reported by Horia.
> If a queue has more than one request, a first crypto_pump_requests() will send a request and for drivers which do not block on do_one_request() crypto_pump_requests() will end.
> Then another crypto_pump_requests() will fire sending a second request while the driver does not support that.

> So we need to replace engine->cur_req by another locking mechanism.
> Perhaps the cleaner is to add a "request count" (increased when do_one_request, decreased in crypto_finalize_request)
> I know that the early version have that and it was removed, but I do not see any better way.
>

The "request count" I've change it to can_enqueue_more, so the hw can
"answer" if it can enqueue or not.

I'll (re)add the cur_req in crypto-engine.
If the new callback, can_enqueue_more, is not implemented the crypto-
engine will work as before - will send requests to hardware, one-by-one,
on crypto_pump_requests, and complete it, on crypto_finalize_request,
and so on.

Thanks,
Iulia

2020-02-07 12:17:48

by Corentin Labbe

[permalink] [raw]
Subject: Re: [PATCH v2 1/2] crypto: engine - support for parallel requests

On Fri, Feb 07, 2020 at 11:26:38AM +0000, Iuliana Prodan wrote:
> On 2/5/2020 9:11 PM, Corentin Labbe wrote:
> > On Tue, Feb 04, 2020 at 02:34:19PM +0200, Iuliana Prodan wrote:
> >> Added support for executing multiple requests, in parallel,
> >> for crypto engine.
> >> A new callback is added, can_enqueue_more, which asks the
> >> driver if the hardware has free space, to enqueue a new request.
> >> The new crypto_engine_alloc_init_and_set function, initialize
> >> crypto-engine, sets the maximum size for crypto-engine software
> >> queue (not hardcoded anymore) and the can_enqueue_more callback.
> >> On crypto_pump_requests, if can_enqueue_more callback returns true,
> >> a new request is send to hardware, until there is no space and the
> >> callback returns false.
> >>
> >> Signed-off-by: Iuliana Prodan <[email protected]>
> >> ---
> >> crypto/crypto_engine.c | 106 ++++++++++++++++++++++++++++++------------------
> >> include/crypto/engine.h | 10 +++--
> >> 2 files changed, 72 insertions(+), 44 deletions(-)
> >>
> >> diff --git a/crypto/crypto_engine.c b/crypto/crypto_engine.c
> >> index eb029ff..aba934f 100644
> >> --- a/crypto/crypto_engine.c
> >> +++ b/crypto/crypto_engine.c
> >> @@ -22,32 +22,18 @@
> >> * @err: error number
> >> */
> >> static void crypto_finalize_request(struct crypto_engine *engine,
> >> - struct crypto_async_request *req, int err)
> >> + 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);
> >> + enginectx = crypto_tfm_ctx(req->tfm);
> >> + if (enginectx->op.prepare_request &&
> >> + enginectx->op.unprepare_request) {
> >> + ret = enginectx->op.unprepare_request(engine, req);
> >> + if (ret)
> >> + dev_err(engine->dev, "failed to unprepare request\n");
> >> }
> >> -
> >> req->complete(req, err);
> >>
> >> kthread_queue_work(engine->kworker, &engine->pump_requests);
> >> @@ -73,10 +59,6 @@ static void crypto_pump_requests(struct crypto_engine *engine,
> >>
> >> spin_lock_irqsave(&engine->queue_lock, flags);
> >>
> >> - /* Make sure we are not already running a request */
> >> - if (engine->cur_req)
> >> - goto out;
> >> -
> >
> > Hello
> >
> > Your patch has the same problem than mine reported by Horia.
> > If a queue has more than one request, a first crypto_pump_requests() will send a request and for drivers which do not block on do_one_request() crypto_pump_requests() will end.
> > Then another crypto_pump_requests() will fire sending a second request while the driver does not support that.
>
> > So we need to replace engine->cur_req by another locking mechanism.
> > Perhaps the cleaner is to add a "request count" (increased when do_one_request, decreased in crypto_finalize_request)
> > I know that the early version have that and it was removed, but I do not see any better way.
> >
>
> The "request count" I've change it to can_enqueue_more, so the hw can
> "answer" if it can enqueue or not.
>
> I'll (re)add the cur_req in crypto-engine.
> If the new callback, can_enqueue_more, is not implemented the crypto-
> engine will work as before - will send requests to hardware, one-by-one,
> on crypto_pump_requests, and complete it, on crypto_finalize_request,
> and so on.
>

But if the crypto_engine use can_enqueue_more, cur_req is a lie, so the name should be changed (or this fact need to be heavy documented on each of its occurence).