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Jeff,
You may have the information on the host side, but if you have a
separate device that has a one bus (such as SAS) that is bridged (via a
card) to say a Parallel ATA HDD, the only way the brdige knows how much data
to transfer is if its in the CDB. This may not be your application, but
this is one of the applications for the CDB.
------------------------------------------------
Curtis E. Stevens
20511 Lake Forest Dr. #C 214-D
Lake Forest, Ca. 92630
Phone: 949-672-7933
Cell: 949-307-5050
E-Mail: [EMAIL PROTECTED]
Why did the chicken cross the road? Colonel Sanders: You mean I missed one?
-----Original Message-----
From: Jeff Garzik [mailto:[EMAIL PROTECTED]
Sent: Thursday, October 21, 2004 6:27 PM
To: Pat LaVarre
Cc: Andy Warner; Curtis Stevens; [EMAIL PROTECTED]
Subject: Re: [t13] RE: comment on T10 ATA-passthru
Pat LaVarre wrote:
>> Well, TBH I think it's redundant information since libata (the Linux
>> implementation, for our fair readers) already carries the data
>> direction implicitly. I cannot see a case where the data direction
>> is not available at all.
>
>
> Vendor-specific & newly standard ops?
The data direction is _always_ provided by the user application creating the
CDB / taskfile.
We can fully support vendor/future ops, without an explicit data direction
in the CDB.
Jeff
