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From:   Alex =?utf-8?Q?Benn=C3=A9e?= <alex.bennee@linaro.org>
To:     Bean Huo <huobean@gmail.com>
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Subject: Re: [PATCH  v2 0/4] rpmb subsystem, uapi and virtio-rpmb driver
Date:   Wed, 06 Apr 2022 12:22:00 +0100
In-reply-to: <aeb64d1c4bbddfd8463c07a40ab1fc78be0d158d.camel@gmail.com>
Message-ID: <87ee2ajuky.fsf@linaro.org>
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Bean Huo <huobean@gmail.com> writes:

> On Tue, 2022-04-05 at 16:43 +0100, Alex Benn=C3=A9e wrote:
>>=20
>> Bean Huo <huobean@gmail.com> writes:
>>=20
>> > Hi Alex,
>> >=20
>> > Thanks for this unified RPMB interface, I wanted to verify this on
>> > our
>> > UFS, it seems you didn't add the UFS access interface in this
>> > version=20
>> > from your userspace tools, right?
>>=20
>> No I didn't but it should be easy enough to add some function pointer
>> redirection everywhere one of the op_* functions calls a vrpmb_*
>> function. Do you already have a UFS RPMB device driver?
>>=20
>
> Hi Alex,
> Thanks for your feedback.
>
> We now access UFS RPMB through the RPMB LUN BSG device, RPMB is a well-
> known LU and we have a userspace tool to access it.
>
> I see that if we're going to use your interface, "static struct
> rpmb_ops" should be registered from a lower-level driver, for example
> in a UFS driver, yes there should be no problem with this registration,
> but I don't know with the current way Compared, what are the advantages
> to add a driver. maybe the main advantage is that we will have an
> unified user space tool for RPMB. right?

Pretty much. The main issue for virtio-rpmb is it doesn't really fit
neatly into the block stack because all it does is the RPMB part so a
non-block orientate API makes sense.

Can you point be to where the UFS driver does it's current RPMB stuff?

>
> Kind regards,
> Bean


--=20
Alex Benn=C3=A9e