[PATCH v3 0/2] crypto: engine - support for parallel and batch requests

[Iuliana Prodan]

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 <iuliana.prodan@xxxxxxx>

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

 crypto/crypto_engine.c  | 132 +++++++++++++++++++++++++++++++++++++-----------
 include/crypto/engine.h |  14 +++--
 2 files changed, 113 insertions(+), 33 deletions(-)

-- 
2.1.0