Re: [PATCH] crypto: af_alg - add async support to algif_aead
From: Herbert Xu
Date: Mon Jan 18 2016 - 19:34:43 EST
On Mon, Jan 18, 2016 at 07:22:55AM -0800, Tadeusz Struk wrote:
> My understanding is that the sock_kmalloc is mainly used for allocations
> of the user provided data, because it keeps tracks of how much memory
> is allocated by a socket, and makes sure that is will not exceed the
> sysctl_optmem_max limit. Usually the internal structures, with fixed
> size are allocated simply with kmalloc. I don't think that using
> sock_kmalloc will give us any benefit here.
If there is only ever one of them per-socket then kmalloc is fine,
otherwise you should use sock_kmalloc.
> > The code in the aead_recvmsg_sync and _async is very very similar with the
> > exception of the areq handling.
> > What I am wondering, is it possible to consolidate both into one, considering
> > that the real difference according to my understanding is the
> > af_alg_wait_for_completion usage (in _sync) vs. the use of a self-written
> > callback (_async)?
> I agree that they are very similar, but I found it much easier to debug
> when they are separate functions. I would prefer to keep them separate.
> They are also separate in algif_skcipher. It makes it also easier to
> read and understand.
I too would prefer a common function. However we can do this
later if we wish.
> The inflight ctr is incremented only if an asynchronous request has been
> successfully en-queued for processing. If a user forges to call recvmsg
> then the function that increments it won't be even called.
> >From the other hand we don't want to give the option to interrupt the
> wait, because in a case, when we do have request being processed by some
> hardware, and the user kills the process, causing the socket to be
> freed, then we will get an Oops in the callback.
This should be replaced with a sock_hold.
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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