1 files changed, 113 insertions, 91 deletions

diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 19c9a232a754..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;
 
@@ -870,15 +880,15 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget,
  out_free_sdev:
 	if (res == SCSI_SCAN_LUN_PRESENT) {
 		if (sdevp) {
-			scsi_device_get(sdev);
-			*sdevp = sdev;
+			if (scsi_device_get(sdev) == 0) {
+				*sdevp = sdev;
+			} else {
+				__scsi_remove_device(sdev);
+				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;
 }
@@ -1050,7 +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];
@@ -1063,7 +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.
@@ -1071,15 +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)
@@ -1094,8 +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;
 
@@ -1197,10 +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",
@@ -1223,13 +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;
 }
 
@@ -1260,6 +1277,19 @@ struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
 }
 EXPORT_SYMBOL(__scsi_add_device);
 
+int scsi_add_device(struct Scsi_Host *host, uint channel,
+		    uint target, uint lun)
+{
+	struct scsi_device *sdev = 
+		__scsi_add_device(host, channel, target, lun, NULL);
+	if (IS_ERR(sdev))
+		return PTR_ERR(sdev);
+
+	scsi_device_put(sdev);
+	return 0;
+}
+EXPORT_SYMBOL(scsi_add_device);
+
 void scsi_rescan_device(struct device *dev)
 {
 	struct scsi_driver *drv;
@@ -1276,32 +1306,12 @@ void scsi_rescan_device(struct device *dev)
 }
 EXPORT_SYMBOL(scsi_rescan_device);
 
-/**
- * scsi_scan_target - scan a target id, possibly including all LUNs on the
- *     target.
- * @sdevsca:	Scsi_Device handle for scanning
- * @shost:	host to scan
- * @channel:	channel to scan
- * @id:		target id to scan
- *
- * Description:
- *     Scan the target id on @shost, @channel, and @id. Scan at least LUN
- *     0, and possibly all LUNs on the target id.
- *
- *     Use the pre-allocated @sdevscan as a handle for the scanning. This
- *     function sets sdevscan->host, sdevscan->id and sdevscan->lun; the
- *     scanning functions modify sdevscan->lun.
- *
- *     First try a REPORT LUN scan, if that does not scan the target, do a
- *     sequential scan of LUNs on the target id.
- **/
-void scsi_scan_target(struct device *parent, unsigned int channel,
-		      unsigned int id, unsigned int lun, int rescan)
+static void __scsi_scan_target(struct device *parent, unsigned int channel,
+		unsigned int id, unsigned int lun, int rescan)
 {
 	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)
@@ -1310,9 +1320,7 @@ void scsi_scan_target(struct device *parent, unsigned int channel,
 		 */
 		return;
 
-
 	starget = scsi_alloc_target(parent, channel, id);
-
 	if (!starget)
 		return;
 
@@ -1329,27 +1337,16 @@ 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
@@ -1358,6 +1355,33 @@ void scsi_scan_target(struct device *parent, unsigned int channel,
 
 	put_device(&starget->dev);
 }
+
+/**
+ * scsi_scan_target - scan a target id, possibly including all LUNs on the
+ *     target.
+ * @parent:	host to scan
+ * @channel:	channel to scan
+ * @id:		target id to scan
+ * @lun:	Specific LUN to scan or SCAN_WILD_CARD
+ * @rescan:	passed to LUN scanning routines
+ *
+ * Description:
+ *     Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
+ *     and possibly all LUNs on the target id.
+ *
+ *     First try a REPORT LUN scan, if that does not scan the target, do a
+ *     sequential scan of LUNs on the target id.
+ **/
+void scsi_scan_target(struct device *parent, unsigned int channel,
+		      unsigned int id, unsigned int lun, int rescan)
+{
+	struct Scsi_Host *shost = dev_to_shost(parent);
+
+	down(&shost->scan_mutex);
+	if (scsi_host_scan_allowed(shost))
+		__scsi_scan_target(parent, channel, id, lun, rescan);
+	up(&shost->scan_mutex);
+}
 EXPORT_SYMBOL(scsi_scan_target);
 
 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
@@ -1383,10 +1407,12 @@ static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
 				order_id = shost->max_id - id - 1;
 			else
 				order_id = id;
-			scsi_scan_target(&shost->shost_gendev, channel, order_id, lun, rescan);
+			__scsi_scan_target(&shost->shost_gendev, channel,
+					order_id, lun, rescan);
 		}
 	else
-		scsi_scan_target(&shost->shost_gendev, channel, id, lun, rescan);
+		__scsi_scan_target(&shost->shost_gendev, channel,
+				id, lun, rescan);
 }
 
 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
@@ -1441,23 +1467,17 @@ EXPORT_SYMBOL(scsi_scan_single_target);
 
 void scsi_forget_host(struct Scsi_Host *shost)
 {
-	struct scsi_target *starget, *tmp;
+	struct scsi_device *sdev;
 	unsigned long flags;
 
-	/*
-	 * Ok, this look a bit strange.  We always look for the first device
-	 * on the list as scsi_remove_device removes them from it - thus we
-	 * also have to release the lock.
-	 * We don't need to get another reference to the device before
-	 * releasing the lock as we already own the reference from
-	 * scsi_register_device that's release in scsi_remove_device.  And
-	 * after that we don't look at sdev anymore.
-	 */
+ restart:
 	spin_lock_irqsave(shost->host_lock, flags);
-	list_for_each_entry_safe(starget, tmp, &shost->__targets, siblings) {
+	list_for_each_entry(sdev, &shost->__devices, siblings) {
+		if (sdev->sdev_state == SDEV_DEL)
+			continue;
 		spin_unlock_irqrestore(shost->host_lock, flags);
-		scsi_remove_target(&starget->dev);
-		spin_lock_irqsave(shost->host_lock, flags);
+		__scsi_remove_device(sdev);
+		goto restart;
 	}
 	spin_unlock_irqrestore(shost->host_lock, flags);
 }
@@ -1484,12 +1504,15 @@ void scsi_forget_host(struct Scsi_Host *shost)
  */
 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
 {
-	struct scsi_device *sdev;
+	struct scsi_device *sdev = NULL;
 	struct scsi_target *starget;
 
+	down(&shost->scan_mutex);
+	if (!scsi_host_scan_allowed(shost))
+		goto out;
 	starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
 	if (!starget)
-		return NULL;
+		goto out;
 
 	sdev = scsi_alloc_sdev(starget, 0, NULL);
 	if (sdev) {
@@ -1497,6 +1520,8 @@ struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
 		sdev->borken = 0;
 	}
 	put_device(&starget->dev);
+ out:
+	up(&shost->scan_mutex);
 	return sdev;
 }
 EXPORT_SYMBOL(scsi_get_host_dev);
@@ -1518,10 +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);