[PATCH v4 00/19] simplify crypto wait for async op

[Gilad Ben-Yossef]

Many users of kernel async. crypto services have a pattern of
starting an async. crypto op and than using a completion
to wait for it to end.

This patch set simplifies this common use case in two ways:

First, by separating the return codes of the case where a
request is queued to a backlog due to the provider being
busy (-EBUSY) from the case the request has failed due
to the provider being busy and backlogging is not enabled
(-EAGAIN).

Next, this change is than built on to create a generic API 
to wait for a async. crypto operation to complete.

The end result is a smaller code base and an API that is
easier to use and more difficult to get wrong.

The patch set was boot tested on x86_64 and arm64 which
at the very least tests the crypto users via testmgr and
tcrypt but I do note that I do not have access to some
of the HW whose drivers are modified nor do I claim I was
able to test all of the corner cases.

The patch set is based upon linux-next release tagged 
next-20170808.

Changes from v3:
- Instead of changing the return code to indicate
  backlog queueing, change the return code to indicate
  transient busy state, as suggested by Herbert Xu.

Changes from v2:
- Patch title changed from "introduce crypto wait for
  async op" to better reflect the current state.
- Rebase on top of latest linux-next.
- Add a new return code of -EIOCBQUEUED for backlog
  queueing, as suggested by Herbert Xu.
- Transform more users to the new API.
- Update the drbg change to account for new init as
  indicated by Stephan Muller.

Changes from v1:
- Address review comments from Eric Biggers.
- Separated out bug fixes of existing code and rebase
  on top of that patch set.
- Rename 'ecr' to 'wait' in fscrypto code.
- Split patch introducing the new API from the change
  moving over the algif code which it originated from
  to the new API.
- Inline crypto_wait_req().
- Some code indentation fixes.

Gilad Ben-Yossef (19):
  crypto: change transient busy return code to -EAGAIN
  crypto: ccm: use -EAGAIN for transient busy indication
  crypto: remove redundant backlog checks on EBUSY
  crypto: marvell/cesa: remove redundant backlog checks on EBUSY
  crypto: introduce crypto wait for async op
  crypto: move algif to generic async completion
  crypto: move pub key to generic async completion
  crypto: move drbg to generic async completion
  crypto: move gcm to generic async completion
  crypto: move testmgr to generic async completion
  fscrypt: move to generic async completion
  dm: move dm-verity to generic async completion
  cifs: move to generic async completion
  ima: move to generic async completion
  crypto: tcrypt: move to generic async completion
  crypto: talitos: move to generic async completion
  crypto: qce: move to generic async completion
  crypto: mediatek: move to generic async completion
  crypto: adapt api sample to use async. op wait

 Documentation/crypto/api-samples.rst |  52 ++-------
 crypto/af_alg.c                      |  27 -----
 crypto/ahash.c                       |  12 +--
 crypto/algapi.c                      |   6 +-
 crypto/algif_aead.c                  |  14 +--
 crypto/algif_hash.c                  |  50 +++++----
 crypto/algif_skcipher.c              |  15 ++-
 crypto/api.c                         |  13 +++
 crypto/asymmetric_keys/public_key.c  |  28 +----
 crypto/cryptd.c                      |   4 +-
 crypto/cts.c                         |   6 +-
 crypto/drbg.c                        |  36 ++-----
 crypto/gcm.c                         |  32 ++----
 crypto/lrw.c                         |   8 +-
 crypto/rsa-pkcs1pad.c                |  16 +--
 crypto/tcrypt.c                      |  84 +++++----------
 crypto/testmgr.c                     | 204 ++++++++++++-----------------------
 crypto/xts.c                         |   8 +-
 drivers/crypto/ccp/ccp-crypto-main.c |   8 +-
 drivers/crypto/ccp/ccp-dev.c         |   7 +-
 drivers/crypto/marvell/cesa.c        |   3 +-
 drivers/crypto/marvell/cesa.h        |   2 +-
 drivers/crypto/mediatek/mtk-aes.c    |  31 +-----
 drivers/crypto/qce/sha.c             |  30 +-----
 drivers/crypto/talitos.c             |  38 +------
 drivers/md/dm-verity-target.c        |  81 ++++----------
 drivers/md/dm-verity.h               |   5 -
 fs/cifs/smb2ops.c                    |  30 +-----
 fs/crypto/crypto.c                   |  28 +----
 fs/crypto/fname.c                    |  36 ++-----
 fs/crypto/fscrypt_private.h          |  10 --
 fs/crypto/keyinfo.c                  |  21 +---
 include/crypto/drbg.h                |   3 +-
 include/crypto/if_alg.h              |  13 ---
 include/linux/crypto.h               |  41 +++++++
 security/integrity/ima/ima_crypto.c  |  56 +++-------
 36 files changed, 316 insertions(+), 742 deletions(-)

-- 
2.1.4