[PATCH v3 01/28] crypto: change backlog return code to -EIOCBQUEUED

[Herbert Xu]

On Sun, Jul 02, 2017 at 05:41:43PM +0300, Gilad Ben-Yossef wrote:
> The crypto API was using the -EBUSY return value to indicate
> both a hard failure to submit a crypto operation into a
> transformation provider when the latter was busy and the backlog
> mechanism was not enabled as well as a notification that the operation
> was queued into the backlog when the backlog mechanism was enabled.
> 
> Having the same return code indicate two very different conditions
> depending on a flag is both error prone and requires extra runtime
> check like the following to discern between the cases:
> 
> 	if (err == -EINPROGRESS ||
> 	    (err == -EBUSY && (ahash_request_flags(req) &
> 			       CRYPTO_TFM_REQ_MAY_BACKLOG)))
> 
> This patch changes the return code used to indicate a crypto op
> was queued in the backlog to -EIOCBQUEUED, thus resolving both
> issues.
> 
> Signed-off-by: Gilad Ben-Yossef <gilad at benyossef.com>

So you're changing the success case from EBUSY to EIOCBQUEUED.
This results in a lot of churn as you have to change every single
driver and caller.

How about changing the error case to use something other than
EBUSY instead?

Thanks,
-- 
Email: Herbert Xu <herbert at gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
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