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From:   Nathan Lynch <nathanl@linux.ibm.com>
To:     Michal =?utf-8?Q?Such=C3=A1nek?= <msuchanek@suse.de>
Cc:     Laurent Dufour <ldufour@linux.ibm.com>,
        Tyrel Datwyler <tyreld@linux.ibm.com>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org,
        Michal Hocko <mhocko@suse.com>, Lee@kitsune.suse.cz,
        Chun-Yi <jlee@suse.com>
Subject: Re: [PATCH] powerpc/pseries: add lparctl driver for
 platform-specific functions
In-Reply-To: <20220914081419.GE28810@kitsune.suse.cz>
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Date:   Thu, 15 Sep 2022 08:43:20 -0500
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Michal Such=C3=A1nek <msuchanek@suse.de> writes:
> On Tue, Sep 13, 2022 at 12:02:42PM -0500, Nathan Lynch wrote:
>> Anyway, of course I intend to support the more complex calls, but
>> supporting the simple calls actually unbreaks a lot of stuff.
>
> The thing is that supporting calls that return more than one page of
> data is absolutely required, and this interface built around fixed size
> data transfer can't do it.

Again, it is appropriate for the system parameter commands and handlers
to deal in small fixed size buffers. Code for VPD retrieval will have to
work differently.

> So it sounds like a ticked for redoing the driver right after it's
> implemented, or ending up with two subtly different interfaces - one for
> the calls that can return multiple pages of data, and one for the simple
> calls.
>
> That does not sound like a good idea at all to me.

That's not my plan, and I won't be trying to get anything merged without
supporting some of the more complex cases. OK?