[PATCH] Report Luns for scsi devices 2.5.10

[PATCH] Report Luns for scsi devices 2.5.10

Here's a patch for SCSI REPORT LUN scanning, including Douglas Gilbert's
recent changes to support a short INQUIRY followed by a longer INQUIRY.

Please apply, or let me know if you think it needs any modifications.

It's against linux-2.5.4. It does _not_ change the size of the linux lun.

A description of the 8 byte LUN layout can be found on page 35 of:

ftp://ftp.t10.org/t10/drafts/scc2/scc2r04.pdf

The above is a draft, but matches the layout seen on most disk arrays
(including EMC, IBM, LSI, and Hitachi). Later drafts (post SCSI-3) have
this information in the SCSI Architectural Model.

Patch description:

Adds REPORT LUN scanning.

Adds Douglas Gilbert's INQUIRY modification so broken devices that cannot handlean INQUIRY
of more than 36 bytes can be black-listed, plus saving the INQUIRY
result in Scsi_Device.

Adds scan_scsis_target function, replacing code in scan_scsis and parts
of scan_scsis_single. This cleans up the scanning code, and removes a
really ugly for loop. It would be difficult to add REPORT LUN scanning
without this change.

Adds missing scsi_release_commandblocks().

No longer sets max_dev_lun out of bounds for BLIST_FORCELUN devices.

Fixes scanning past LUN 7 for SCSI-3 devices (the patch in 2.4.17
for that fix will not cleanly apply against this code).

-- Patrick Mansfield