SCSI & usb-storage: add flags for VPD pages and REPORT LUNS
This patch (as1507) adds a skip_vpd_pages flag to struct scsi_device
and a no_report_luns flag to struct scsi_target. The first is used to
control whether sd will look at VPD pages for information on block
provisioning, limits, and characteristics. The second prevents
scsi_report_lun_scan() from issuing a REPORT LUNS command.
The patch also modifies usb-storage to set the new flag bits for all
USB devices and targets, and to stop adjusting the scsi_level value.
Historically we have seen that USB mass-storage devices often don't
support VPD pages or REPORT LUNS properly. Until now we have avoided
these things by setting the scsi_level to SCSI_2 for all USB devices.
But this has the side effect of storing the LUN bits into the second
byte of each CDB, and now we have a report of a device which doesn't
like that. The best solution is to stop abusing scsi_level and
instead have separate flags for VPD pages and REPORT LUNS.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Reported-by: Perry Wagle <wagle@mac.com>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 89da43f..fd37bfb 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -1295,6 +1295,7 @@
* LUNs even if it's older than SCSI-3.
* If BLIST_NOREPORTLUN is set, return 1 always.
* If BLIST_NOLUN is set, return 0 always.
+ * If starget->no_report_luns is set, return 1 always.
*
* Return:
* 0: scan completed (or no memory, so further scanning is futile)
@@ -1321,6 +1322,7 @@
* Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
* Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
* support more than 8 LUNs.
+ * Don't attempt if the target doesn't support REPORT LUNS.
*/
if (bflags & BLIST_NOREPORTLUN)
return 1;
@@ -1332,6 +1334,8 @@
return 1;
if (bflags & BLIST_NOLUN)
return 0;
+ if (starget->no_report_luns)
+ return 1;
if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
sdev = scsi_alloc_sdev(starget, 0, NULL);