On Tue, 2017-07-18 at 17:52 -0700, Tim Chen wrote:
> On 07/17/2017 10:41 PM, Herbert Xu wrote:
> > On Tue, Jun 27, 2017 at 05:26:13PM -0700, Megha Dey wrote:
> >>
> >> +static void completion_callback(struct mcryptd_skcipher_request_ctx *rctx,
> >> + struct mcryptd_alg_cstate *cstate,
> >> + int err)
> >> +{
> >> + struct skcipher_request *req = cast_mcryptd_ctx_to_req(rctx);
> >> +
> >> + /* remove from work list and invoke completion callback */
> >> + spin_lock(&cstate->work_lock);
> >> + list_del(&rctx->waiter);
> >> + spin_unlock(&cstate->work_lock);
> >> +
> >> + if (irqs_disabled())
> >> + rctx->complete(&req->base, err);
> >> + else {
> >> + local_bh_disable();
> >> + rctx->complete(&req->base, err);
> >> + local_bh_enable();
> >> + }
> >> +}
> >
> > The fact that you need to do this check means that this design is
> > wrong. You should always know what context you are in.
> >
>
> I think you are right. The irqs_disabled check is not necessary
> as we only call this function in the context of the mcryptd thread.
> When I wrote the original mb algorithms I was probably unsure
> and put this check in as a precaution in other mb algorithms and
> Megha did the same.
I will make this change.
>
> >> +/*
> >> + * CRYPTO_ALG_ASYNC flag is passed to indicate we have an ablk
> >> + * scatter-gather walk.
> >> + */
> >> +static struct skcipher_alg aes_cbc_mb_alg = {
> >> + .base = {
> >> + .cra_name = "cbc(aes)",
> >> + .cra_driver_name = "cbc-aes-aesni-mb",
> >> + .cra_priority = 500,
> >> + .cra_flags = CRYPTO_ALG_INTERNAL,
> >> + .cra_blocksize = AES_BLOCK_SIZE,
> >> + .cra_ctxsize = CRYPTO_AES_CTX_SIZE,
> >> + .cra_module = THIS_MODULE,
> >> + },
> >> + .min_keysize = AES_MIN_KEY_SIZE,
> >> + .max_keysize = AES_MAX_KEY_SIZE,
> >> + .ivsize = AES_BLOCK_SIZE,
> >> + .setkey = aes_set_key,
> >> + .encrypt = mb_aes_cbc_encrypt,
> >> + .decrypt = mb_aes_cbc_decrypt
> >> +};
> >
> > So this claims to be a sync algorithm. Is this really the case?
yes, the inner algorithm is sync whereas the outer algorithm is async.
> >
> > Cheers,
> >
>
