[SCSI] Try LUN 1 and use bflags

Some devices report a peripheral qualifier of 3 for LUN 0; with the original
code, we would still try a REPORT_LUNS scan (if SCSI level is >= 3 or if we
have the BLIST_REPORTLUNS2 passed in), but NOT any sequential scan.
Also, the device at LUN 0 (which is not connected according to the PQ) is not
registered with the OS.

Unfortunately, SANs exist that are SCSI-2 and do NOT support REPORT_LUNS, but
report a unknown device with PQ 3 on LUN 0. We still need to scan them, and
most probably we even need BLIST_SPARSELUN (and BLIST_LARGELUN). See the bug
reference for an infamous example.

This is patch 1/3:
If we end up in sequential scan, at least try LUN 1 for devices
that reported a PQ of 3 for LUN 0.
Also return blacklist flags, even for PQ3 devices.

Signed-off-by: Kurt Garloff <garloff@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index f149459..820c4ad 100644 (file)
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -872,6 +872,8 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
        if (scsi_probe_lun(sdev, result, result_len, &bflags))
                goto out_free_result;
 
+       if (bflagsp)
+               *bflagsp = bflags;
        /*
         * result contains valid SCSI INQUIRY data.
         */
@@ -912,8 +914,6 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
                        sdev->lockable = 0;
                        scsi_unlock_floptical(sdev, result);
                }
-               if (bflagsp)
-                       *bflagsp = bflags;
        }
 
  out_free_result:
@@ -938,7 +938,6 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
  * scsi_sequential_lun_scan - sequentially scan a SCSI target
  * @starget:   pointer to target structure to scan
  * @bflags:    black/white list flag for LUN 0
- * @lun0_res:  result of scanning LUN 0
  *
  * Description:
  *     Generally, scan from LUN 1 (LUN 0 is assumed to already have been
@@ -948,8 +947,7 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
  *     Modifies sdevscan->lun.
  **/
 static void scsi_sequential_lun_scan(struct scsi_target *starget,
-                                    int bflags, int lun0_res, int scsi_level,
-                                    int rescan)
+                                    int bflags, int scsi_level, int rescan)
 {
        unsigned int sparse_lun, lun, max_dev_lun;
        struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
@@ -970,13 +968,6 @@ static void scsi_sequential_lun_scan(struct scsi_target *starget,
                sparse_lun = 0;
 
        /*
-        * If not sparse lun and no device attached at LUN 0 do not scan
-        * any further.
-        */
-       if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT))
-               return;
-
-       /*
         * If less than SCSI_1_CSS, and no special lun scaning, stop
         * scanning; this matches 2.4 behaviour, but could just be a bug
         * (to continue scanning a SCSI_1_CSS device).
@@ -1384,7 +1375,7 @@ static void __scsi_scan_target(struct device *parent, unsigned int channel,
                         * do a sequential scan.
                         */
                        scsi_sequential_lun_scan(starget, bflags,
-                                       res, starget->scsi_level, rescan);
+                                                starget->scsi_level, rescan);
        }
 
  out_reap: