Re: [PATCH repost 3] [SCSI] Retrieve the Caching mode page

Luben Tuikov
2010-12-08T00:09:08Z

--- On Sun, 12/5/10, Luben Tuikov <ltuikov@yahoo.com> wrote:
> --- On Wed, 11/24/10, Luben Tuikov
> <ltuikov@yahoo.com>
> wrote:
> >
> > CBI/BBB isn't supposed to be, nor is designed to
> support
> > SAM-modern devices. So while REQUEST LUN /may/ work on
> some
> > devices which implement it in their firmware, it is
> NOT a
> > requirement for those devices as they are not required
> to
> > adhere to any SAM version. Those transport protocols
> define
> > a class-specific request to get the maximum LUN, and
> another
> > to reset the target port (instead of I_T Reset or LU
> Reset).
> > They also do not support SCSI Status completion of
> the
> > command, nor Autosense. They also do not provide TMFs.
> They
> > provide none of the SCSI transport protocol services
> in
> > support of the Execute Command procedure call. The
> SCSI
> > layer shouldn't be trying to guess their "SCSI
> version", and
> > or treat them as real SCSI devices sending REPORT
> LUNs, etc.
> > commands.
> >
> > Newer, modern transport protocols over USB, are part
> of
> > SAM, and it is devices who connect via those protocols
> that
> > are being disadvantaged, due to the adoption
> (assumption) of
> > CBI/BBB well into the SCSI layer.
> >
> > To this effect, the transport protocol can tell upper
> > layers if the device is true SCSI (new usb transports
> or
> > other) or hybrid (usb-storage). In the former case,
> the
> > device is a SCSI device, in the latter, only basic
> commands
> > should be attempted.
> >
> > This isn't to say that firmware for those devices
> wouldn't
> > be buggy. Of course it will, and most will probably
> port
> > their legacy FW over to the new SPTL, but the
> protocol
> > requirements are there by design (i.e. there is no
> longer
> > Get Max Lun class-specific request, the application
> client
> > has to send REPORT LUNS, and FW has to answer it) and
> we
> > have to accommodate that.
> >
> > It is in this spirit that this patch doesn't change
> wire
> > behavior, but simply parses data returned by a
> command
> > already supported by older protocols.
>
> Did anyone pick up this patch?

It's been over 6 weeks now that this patch's been in these mailing lists.
Will anyone pick up this patch, or should I stop posting it every week? Please let me know--it's been posted here 6 times in the last 6 weeks.

Thanks,
Luben