[PATCH v5 1/3] crypto: algapi - create function to add request in front of queue

[Iuliana Prodan]

Add crypto_enqueue_request_head function that enqueues a
MAY_BACKLOG request in front of queue.
This will be used in crypto-engine, on error path. In case a request
was not executed by hardware, enqueue it back in front of queue (to
keep the order of requests).

Signed-off-by: Iuliana Prodan <iuliana.prodan@xxxxxxx>
---
 crypto/algapi.c         | 11 +++++++++++
 include/crypto/algapi.h |  2 ++
 2 files changed, 13 insertions(+)

diff --git a/crypto/algapi.c b/crypto/algapi.c
index 69605e21af92..a8732e8e7843 100644
--- a/crypto/algapi.c
+++ b/crypto/algapi.c
@@ -904,6 +904,17 @@ int crypto_enqueue_request(struct crypto_queue *queue,
 }
 EXPORT_SYMBOL_GPL(crypto_enqueue_request);
 
+void crypto_enqueue_request_head(struct crypto_queue *queue,
+				 struct crypto_async_request *request)
+{
+	/* only backlog requests can be enqueued */
+	BUG_ON(!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG));
+
+	queue->qlen++;
+	list_add(&request->list, &queue->list);
+}
+EXPORT_SYMBOL_GPL(crypto_enqueue_request_head);
+
 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue)
 {
 	struct list_head *request;
diff --git a/include/crypto/algapi.h b/include/crypto/algapi.h
index e115f9215ed5..00a9cf98debe 100644
--- a/include/crypto/algapi.h
+++ b/include/crypto/algapi.h
@@ -125,6 +125,8 @@ int crypto_inst_setname(struct crypto_instance *inst, const char *name,
 void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen);
 int crypto_enqueue_request(struct crypto_queue *queue,
 			   struct crypto_async_request *request);
+void crypto_enqueue_request_head(struct crypto_queue *queue,
+				 struct crypto_async_request *request);
 struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue);
 static inline unsigned int crypto_queue_len(struct crypto_queue *queue)
 {
-- 
2.17.1