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Subject: Re: [PATCH] lightnvm: move device L2P detection to core
To:     javier@cnexlabs.com
Cc:     igor.j.konopko@intel.com, marcin.dziegielewski@intel.com,
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References: <20180803085449.3436-1-mb@lightnvm.io>
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From:   =?UTF-8?Q?Matias_Bj=c3=b8rling?= <mb@lightnvm.io>
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Date:   Fri, 3 Aug 2018 14:37:41 +0200
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On 08/03/2018 02:16 PM, Javier Gonzalez wrote:
>> On 3 Aug 2018, at 10.54, Matias Bjørling <mb@lightnvm.io> wrote:
>>
>> A 1.2 device is able to manage the logical to physical mapping
>> table internally or leave it to the host.
>>
>> A target only supports one of those approaches, and therefore must
>> check on initialization. Move this check to core to avoid each target
>> implement the check.
>>
>> Signed-off-by: Matias Bjørling <mb@lightnvm.io>
>> ---
> 
> 
> I see where you want to go with these changes, but the way targets are
> layered on top of the LightNVM subsystem does not align with it.
> LightNVM can support different OCSSD versions and capabilities, but that
> does not mean that a target (e.g., pblk) does. The way I see it, core
> should only check for (i) the drive to expose itself in a known revision
> and (ii) the reported structures to be consistent. However, specific
> functionality is not for core to check upo.

Why try to initialize a target, if we already know that it is incompatible?