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SubjectRe: [PATCH 5/5] falconide/q40ide: add ->atapi_*put_bytes and ->ata_*put_data methods
Hi,

>> v2:
>> * Add 'struct request *rq' argument to ->ata_{in,out}put_data methods
>> and don't byte-swap disk fs requests (we shouldn't un-swap fs requests
>> because fs itself is stored byte-swapped on the disk) - this is how
>> things were done before the patch (ideally device mapper should be
>> used instead but it would break existing setups and would have some
>> performance impact).
>
> I like the part about checking 'struct request *rq', will make a clean
> distinction between ide command data and ide disk/medium data which is badly
> needed.
>
> However, not only FS data is byteswapped, complete disk including partition
> table and everything else is. Will "rq->cmd_type == REQ_TYPE_FS" also catch
> all these cases?

IIRC only identify data (and perhaps ATAPI data) need to be byteswapped
twice (or not at all), so REQ_TYPE_FS should catch all other cases.

(Good catch about ATAPI there, BTW - I never thought about that, and ISTR
that IDE CD-ROMs never worked in Linux. That would be the reason why..)

Michael


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