Re: [usb-storage] [Merging ATA passthru] on integrating SMART/ATA-Security in usb-storage driver

Alan Stern
2005-11-07T17:46:40Z

On Mon, 7 Nov 2005, Patrick Mansfield wrote:

> On Mon, Nov 07, 2005 at 09:05:25AM -0800, Matthew Dharm wrote:
>
> > Okay, what am I missing?
> >
> > Looking at that patch, it looks to me like if sg.c set a flag in the SCSI
> > command block then scsi_core.c could use that flag in the test to determine
> > if the LUN should be masked-in.
> >
> > HOWEVER, I keep hearing that the changes will be extensive. What am I
> > missing?
>
> Not extensive AFAICT ...
>
> The scmd/cdb is not available until we call scsi_get_command() in the
> request function. So you would have to add a field into scsi_request, set
> it in sg (in both sg.c block/scsi_ioctl.c, test via sd and sg when you are
> done), and add the field in scsi_cmnd, and set scmd one in
> scsi_init_cmd_from_req().

Isn't it true that scsi_request is going away? Everything will have to
use generic request structures.

> But as far as black listing, it does seem like a better solution in that
> user apps do not need special code.

I don't think blacklisting is a good way to do this. In principle any USB
mass storage device -- any SCSI device, in fact -- might have a
vendor-specific pass-thru needing special handling. It doesn't have to be
correlated with the vendor, the product, the SCSI level, the transport, or
anything else.

Alan Stern