Re: [PATCH 1/1] scsi: retrieve cache mode using ATA_16 if normal routine fails

Amit Sahrawat
2011-12-13T12:15:53Z

On Tue, Dec 13, 2011 at 2:23 PM, James Bottomley
<James.Bottomley@hansenpartnership.com> wrote:
> On Tue, 2011-12-13 at 09:20 +0900, Namjae Jeon wrote:
>> > This whole patch looks like a layering violation.  Why not just update
>> > the SAT layer to translate the MODE SENSE correctly?
>> Would plz you explain more ? I didn't clearly understand your point yet.
>
> The ATA layer does translation for SCSI commands.  Just translate the
> mode sense correctly to use IDENTIFY word 85.  It's a smaller patch and
> no need for any changes in SCSI.
I have a confusion to this, can you please guide where exactly to look for this.
Is there any existing solution to this problem? I did a lot of
analysis and actually tried to make use of a number of USB HDD's from
different vendors to be very sure of my observations. Our's is a
target where-in we connect our HDD through the USB interface.
Do you mean that putting code changes at this place would have impact
on SATA HDD?
Please help more on this.
>
> Actually, looking at it, it seems to be correct ... why is it not
> working for you?
Again, if possible please share that code point, We can again check if
that is hitting in our case.
If need be I can provide the list of all the HDDs with their
manufaturer ID's - on which we tested.
Please let me know for this.
>
> James
>
>
Thanks & Regards,
Amit Sahrawat