Added support for executing multiple, independent or not, requests for crypto engine based on a retry mechanism. If hardware was unable to execute a backlog request, enqueue it back in front of crypto-engine queue, to keep the order of requests. Now do_one_request() returns: >= 0: hardware executed the request successfully; < 0: this is the old error path. If hardware has support for retry mechanism, the backlog request is put back in front of crypto-engine queue. For backwards compatibility, if the retry support is not available, the crypto-engine will work as before. Only MAY_BACKLOG requests are enqueued back into crypto-engine's queue, since the others can be dropped. 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 callback is NULL and retry mechanism is disabled, so crypto-engine will work as before these changes; - to support multiple requests, in parallel, retry_support variable must be set on true, in driver. - 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(). --- Changes since V4: - added, in algapi a function to add a request in front of queue; - added a retry mechanism: if hardware is unable to execute a backlog request, enqueue it back in front of crypto-engine queue, to keep the order of requests. Changes since V3: - removed can_enqueue_hardware callback and added a start-stop mechanism based on the on the return value of do_one_request(). Changes since V2: - readded cur_req in crypto-engine, to keep, the exact behavior as before these changes, if can_enqueue_more is not implemented: send requests to hardware, _one-by-one_, on crypto_pump_requests, and complete it, on crypto_finalize_request, and so on. - do_batch_requests is available only with can_enqueue_more. 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 (3): crypto: algapi - create function to add request in front of queue crypto: engine - support for parallel requests based on retry mechanism crypto: engine - support for batch requests crypto/algapi.c | 11 +++ crypto/crypto_engine.c | 165 ++++++++++++++++++++++++++++++++-------- include/crypto/algapi.h | 2 + include/crypto/engine.h | 15 +++- 4 files changed, 161 insertions(+), 32 deletions(-) -- 2.17.1