[SCSI] allow REPORT LUN scanning even for LUN 0 PQ of 3

Currently we just ignore the device, which means there are a few
arrays out there that we don't find.

This patch updates the scsi_report_lun_scan() to take a target instead
of a device so it can be called on a return of
SCSI_SCAN_TARGET_PRESENT, which is what a PQ 3 device returns.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 47 insertions, 49 deletions

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index fcf9f6cbb142..327c5d7e5bd2 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -587,6 +587,7 @@ static int scsi_probe_lun(struct scsi_device *sdev, char *inq_result,
         if (sdev->scsi_level >= 2 ||
             (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
                 sdev->scsi_level++;
+        sdev->sdev_target->scsi_level = sdev->scsi_level;
 
         return 0;
 }
@@ -771,6 +772,15 @@ static int scsi_add_lun(struct scsi_device *sdev, char *inq_result, int *bflags)
         return SCSI_SCAN_LUN_PRESENT;
 }
 
+static inline void scsi_destroy_sdev(struct scsi_device *sdev)
+{
+        if (sdev->host->hostt->slave_destroy)
+                sdev->host->hostt->slave_destroy(sdev);
+        transport_destroy_device(&sdev->sdev_gendev);
+        put_device(&sdev->sdev_gendev);
+}
+
+
 /**
  * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
  * @starget:    pointer to target device structure
@@ -803,9 +813,9 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
          * The rescan flag is used as an optimization, the first scan of a
          * host adapter calls into here with rescan == 0.
          */
-        if (rescan) {
-                sdev = scsi_device_lookup_by_target(starget, lun);
-                if (sdev) {
+        sdev = scsi_device_lookup_by_target(starget, lun);
+        if (sdev) {
+                if (rescan || sdev->sdev_state != SDEV_CREATED) {
                         SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
                                 "scsi scan: device exists on %s\n",
                                 sdev->sdev_gendev.bus_id));
@@ -820,9 +830,9 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
                                                                  sdev->model);
                         return SCSI_SCAN_LUN_PRESENT;
                 }
-        }
-
-        sdev = scsi_alloc_sdev(starget, lun, hostdata);
+                scsi_device_put(sdev);
+        } else
+                sdev = scsi_alloc_sdev(starget, lun, hostdata);
         if (!sdev)
                 goto out;
 
@@ -877,12 +887,8 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
                                 res = SCSI_SCAN_NO_RESPONSE;
                         }
                 }
-        } else {
-                if (sdev->host->hostt->slave_destroy)
-                        sdev->host->hostt->slave_destroy(sdev);
-                transport_destroy_device(&sdev->sdev_gendev);
-                put_device(&sdev->sdev_gendev);
-        }
+        } else
+                scsi_destroy_sdev(sdev);
  out:
         return res;
 }
@@ -1054,7 +1060,7 @@ EXPORT_SYMBOL(int_to_scsilun);
  *     0: scan completed (or no memory, so further scanning is futile)
  *     1: no report lun scan, or not configured
  **/
-static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
+static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
                                 int rescan)
 {
         char devname[64];
@@ -1067,7 +1073,8 @@ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
         struct scsi_lun *lunp, *lun_data;
         u8 *data;
         struct scsi_sense_hdr sshdr;
-        struct scsi_target *starget = scsi_target(sdev);
+        struct scsi_device *sdev;
+        struct Scsi_Host *shost = dev_to_shost(&starget->dev);
 
         /*
          * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
@@ -1075,15 +1082,23 @@ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
          * support more than 8 LUNs.
          */
         if ((bflags & BLIST_NOREPORTLUN) || 
-             sdev->scsi_level < SCSI_2 ||
-            (sdev->scsi_level < SCSI_3 && 
-             (!(bflags & BLIST_REPORTLUN2) || sdev->host->max_lun <= 8)) )
+             starget->scsi_level < SCSI_2 ||
+            (starget->scsi_level < SCSI_3 && 
+             (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8)) )
                 return 1;
         if (bflags & BLIST_NOLUN)
                 return 0;
 
+        if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
+                sdev = scsi_alloc_sdev(starget, 0, NULL);
+                if (!sdev)
+                        return 0;
+                if (scsi_device_get(sdev))
+                        return 0;
+        }
+
         sprintf(devname, "host %d channel %d id %d",
-                sdev->host->host_no, sdev->channel, sdev->id);
+                shost->host_no, sdev->channel, sdev->id);
 
         /*
          * Allocate enough to hold the header (the same size as one scsi_lun)
@@ -1098,8 +1113,10 @@ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
         length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
         lun_data = kmalloc(length, GFP_ATOMIC |
                            (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
-        if (!lun_data)
+        if (!lun_data) {
+                printk(ALLOC_FAILURE_MSG, __FUNCTION__);
                 goto out;
+        }
 
         scsi_cmd[0] = REPORT_LUNS;
 
@@ -1201,10 +1218,6 @@ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
                         for (i = 0; i < sizeof(struct scsi_lun); i++)
                                 printk("%02x", data[i]);
                         printk(" has a LUN larger than currently supported.\n");
-                } else if (lun == 0) {
-                        /*
-                         * LUN 0 has already been scanned.
-                         */
                 } else if (lun > sdev->host->max_lun) {
                         printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
                                " than allowed by the host adapter\n",
@@ -1227,13 +1240,13 @@ static int scsi_report_lun_scan(struct scsi_device *sdev, int bflags,
         }
 
         kfree(lun_data);
-        return 0;
-
  out:
-        /*
-         * We are out of memory, don't try scanning any further.
-         */
-        printk(ALLOC_FAILURE_MSG, __FUNCTION__);
+        scsi_device_put(sdev);
+        if (sdev->sdev_state == SDEV_CREATED)
+                /*
+                 * the sdev we used didn't appear in the report luns scan
+                 */
+                scsi_destroy_sdev(sdev);
         return 0;
 }
 
@@ -1299,7 +1312,6 @@ static void __scsi_scan_target(struct device *parent, unsigned int channel,
         struct Scsi_Host *shost = dev_to_shost(parent);
         int bflags = 0;
         int res;
-        struct scsi_device *sdev = NULL;
         struct scsi_target *starget;
 
         if (shost->this_id == id)
@@ -1325,27 +1337,16 @@ static void __scsi_scan_target(struct device *parent, unsigned int channel,
          * Scan LUN 0, if there is some response, scan further. Ideally, we
          * would not configure LUN 0 until all LUNs are scanned.
          */
-        res = scsi_probe_and_add_lun(starget, 0, &bflags, &sdev, rescan, NULL);
-        if (res == SCSI_SCAN_LUN_PRESENT) {
-                if (scsi_report_lun_scan(sdev, bflags, rescan) != 0)
+        res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
+        if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
+                if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
                         /*
                          * The REPORT LUN did not scan the target,
                          * do a sequential scan.
                          */
                         scsi_sequential_lun_scan(starget, bflags,
-                                        res, sdev->scsi_level, rescan);
-        } else if (res == SCSI_SCAN_TARGET_PRESENT) {
-                /*
-                 * There's a target here, but lun 0 is offline so we
-                 * can't use the report_lun scan.  Fall back to a
-                 * sequential lun scan with a bflags of SPARSELUN and
-                 * a default scsi level of SCSI_2
-                 */
-                scsi_sequential_lun_scan(starget, BLIST_SPARSELUN,
-                                SCSI_SCAN_TARGET_PRESENT, SCSI_2, rescan);
+                                        res, starget->scsi_level, rescan);
         }
-        if (sdev)
-                scsi_device_put(sdev);
 
  out_reap:
         /* now determine if the target has any children at all
@@ -1542,10 +1543,7 @@ void scsi_free_host_dev(struct scsi_device *sdev)
 {
         BUG_ON(sdev->id != sdev->host->this_id);
 
-        if (sdev->host->hostt->slave_destroy)
-                sdev->host->hostt->slave_destroy(sdev);
-        transport_destroy_device(&sdev->sdev_gendev);
-        put_device(&sdev->sdev_gendev);
+        scsi_destroy_sdev(sdev);
 }
 EXPORT_SYMBOL(scsi_free_host_dev);