On Sat, May 27 2000, Paul Gortmaker wrote:
> > To Do
> > -----
> > Linux sends a 1K buffer with SCSI inquiries. The ANSI-SCSI limit is 255.
>
> I don't see how this can be. In scan_scsis() scsi_result0[256] is
> declared, and if that isn't appropriate for host needing DMA then
> we kmalloc(512, GFP_DMA) - either way it doesn't matter since the
> allocation length field in the CCB for INQUIRY is only a byte (and
> we set it to 255). Even scsi_wait_req() is told the the result buffer
> length is 255 when the INQUIRY command is lodged.
Exactly, I told Alan this several weeks ago also.
> > Linux uses TEST_UNIT_READY to chck for device presence on a PUN/LUN. The
> > INQUIRY is the only valid test allowed by the spec.
>
> The draft of SCSI-2 spec I have here hints that INQUIRY should be used
> to probe system configuration and that TEST_UNIT_READY is more for
> polling on devices with removable media. I tossed the TEST_UNIT_READY
> part out and INQUIRY alone works fine (one disk, 2 CDs and a tape on
> a BusLogic clone - all found as per usual).
Looks good to me. Although I can't possibly see what harm a TEST_UNIT_READY
command could do...
-- * Jens Axboe <axboe@suse.de> * Linux CD/DVD-ROM, SuSE Labs * http://kernel.dk- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.rutgers.edu Please read the FAQ at http://www.tux.org/lkml/
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