1 files changed, 63 insertions, 45 deletions

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 9a1dc0cea03..8613a131771 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -177,24 +177,38 @@ static inline struct scsi_disk *scsi_disk(struct gendisk *disk)
 	return container_of(disk->private_data, struct scsi_disk, driver);
 }
 
-static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
+static struct scsi_disk *__scsi_disk_get(struct gendisk *disk)
 {
 	struct scsi_disk *sdkp = NULL;
 
+	if (disk->private_data) {
+		sdkp = scsi_disk(disk);
+		if (scsi_device_get(sdkp->device) == 0)
+			kref_get(&sdkp->kref);
+		else
+			sdkp = NULL;
+	}
+	return sdkp;
+}
+
+static struct scsi_disk *scsi_disk_get(struct gendisk *disk)
+{
+	struct scsi_disk *sdkp;
+
 	down(&sd_ref_sem);
-	if (disk->private_data == NULL)
-		goto out;
-	sdkp = scsi_disk(disk);
-	kref_get(&sdkp->kref);
-	if (scsi_device_get(sdkp->device))
-		goto out_put;
+	sdkp = __scsi_disk_get(disk);
 	up(&sd_ref_sem);
 	return sdkp;
+}
 
- out_put:
-	kref_put(&sdkp->kref, scsi_disk_release);
-	sdkp = NULL;
- out:
+static struct scsi_disk *scsi_disk_get_from_dev(struct device *dev)
+{
+	struct scsi_disk *sdkp;
+
+	down(&sd_ref_sem);
+	sdkp = dev_get_drvdata(dev);
+	if (sdkp)
+		sdkp = __scsi_disk_get(sdkp->disk);
 	up(&sd_ref_sem);
 	return sdkp;
 }
@@ -716,16 +730,17 @@ static int sd_sync_cache(struct scsi_device *sdp)
 
 static int sd_issue_flush(struct device *dev, sector_t *error_sector)
 {
+	int ret = 0;
 	struct scsi_device *sdp = to_scsi_device(dev);
-	struct scsi_disk *sdkp = dev_get_drvdata(dev);
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
 
 	if (!sdkp)
                return -ENODEV;
 
-	if (!sdkp->WCE)
-		return 0;
-
-	return sd_sync_cache(sdp);
+	if (sdkp->WCE)
+		ret = sd_sync_cache(sdp);
+	scsi_disk_put(sdkp);
+	return ret;
 }
 
 static void sd_end_flush(request_queue_t *q, struct request *flush_rq)
@@ -756,21 +771,24 @@ static int sd_prepare_flush(request_queue_t *q, struct request *rq)
 	struct scsi_device *sdev = q->queuedata;
 	struct scsi_disk *sdkp = dev_get_drvdata(&sdev->sdev_gendev);
 
-	if (sdkp->WCE) {
-		memset(rq->cmd, 0, sizeof(rq->cmd));
-		rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER;
-		rq->timeout = SD_TIMEOUT;
-		rq->cmd[0] = SYNCHRONIZE_CACHE;
-		return 1;
-	}
+	if (!sdkp || !sdkp->WCE)
+		return 0;
 
-	return 0;
+	memset(rq->cmd, 0, sizeof(rq->cmd));
+	rq->flags |= REQ_BLOCK_PC | REQ_SOFTBARRIER;
+	rq->timeout = SD_TIMEOUT;
+	rq->cmd[0] = SYNCHRONIZE_CACHE;
+	return 1;
 }
 
 static void sd_rescan(struct device *dev)
 {
-	struct scsi_disk *sdkp = dev_get_drvdata(dev);
-	sd_revalidate_disk(sdkp->disk);
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
+
+	if (sdkp) {
+		sd_revalidate_disk(sdkp->disk);
+		scsi_disk_put(sdkp);
+	}
 }
 
 
@@ -1253,14 +1271,13 @@ got_data:
 		 * Jacques Gelinas (Jacques@solucorp.qc.ca)
 		 */
 		int hard_sector = sector_size;
-		sector_t sz = sdkp->capacity * (hard_sector/256);
+		sector_t sz = (sdkp->capacity/2) * (hard_sector/256);
 		request_queue_t *queue = sdp->request_queue;
-		sector_t mb;
+		sector_t mb = sz;
 
 		blk_queue_hardsect_size(queue, hard_sector);
 		/* avoid 64-bit division on 32-bit platforms */
-		mb = sz >> 1;
-		sector_div(sz, 1250);
+		sector_div(sz, 625);
 		mb -= sz - 974;
 		sector_div(mb, 1950);
 
@@ -1535,8 +1552,8 @@ static int sd_probe(struct device *dev)
 	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)
 		goto out;
 
-	SCSI_LOG_HLQUEUE(3, printk("sd_attach: scsi device: <%d,%d,%d,%d>\n", 
-			 sdp->host->host_no, sdp->channel, sdp->id, sdp->lun));
+	SCSI_LOG_HLQUEUE(3, sdev_printk(KERN_INFO, sdp,
+					"sd_attach\n"));
 
 	error = -ENOMEM;
 	sdkp = kmalloc(sizeof(*sdkp), GFP_KERNEL);
@@ -1562,6 +1579,7 @@ static int sd_probe(struct device *dev)
 	if (error)
 		goto out_put;
 
+	get_device(&sdp->sdev_gendev);
 	sdkp->device = sdp;
 	sdkp->driver = &sd_template;
 	sdkp->disk = gd;
@@ -1608,10 +1626,8 @@ static int sd_probe(struct device *dev)
 	dev_set_drvdata(dev, sdkp);
 	add_disk(gd);
 
-	printk(KERN_NOTICE "Attached scsi %sdisk %s at scsi%d, channel %d, "
-	       "id %d, lun %d\n", sdp->removable ? "removable " : "",
-	       gd->disk_name, sdp->host->host_no, sdp->channel,
-	       sdp->id, sdp->lun);
+	sdev_printk(KERN_NOTICE, sdp, "Attached scsi %sdisk %s\n",
+		    sdp->removable ? "removable " : "", gd->disk_name);
 
 	return 0;
 
@@ -1640,7 +1656,9 @@ static int sd_remove(struct device *dev)
 
 	del_gendisk(sdkp->disk);
 	sd_shutdown(dev);
+
 	down(&sd_ref_sem);
+	dev_set_drvdata(dev, NULL);
 	kref_put(&sdkp->kref, scsi_disk_release);
 	up(&sd_ref_sem);
 
@@ -1666,8 +1684,8 @@ static void scsi_disk_release(struct kref *kref)
 	spin_unlock(&sd_index_lock);
 
 	disk->private_data = NULL;
-
 	put_disk(disk);
+	put_device(&sdkp->device->sdev_gendev);
 
 	kfree(sdkp);
 }
@@ -1680,18 +1698,18 @@ static void scsi_disk_release(struct kref *kref)
 static void sd_shutdown(struct device *dev)
 {
 	struct scsi_device *sdp = to_scsi_device(dev);
-	struct scsi_disk *sdkp = dev_get_drvdata(dev);
+	struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev);
 
 	if (!sdkp)
 		return;         /* this can happen */
 
-	if (!sdkp->WCE)
-		return;
-
-	printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n",
-			sdkp->disk->disk_name);
-	sd_sync_cache(sdp);
-}	
+	if (sdkp->WCE) {
+		printk(KERN_NOTICE "Synchronizing SCSI cache for disk %s: \n",
+				sdkp->disk->disk_name);
+		sd_sync_cache(sdp);
+	}
+	scsi_disk_put(sdkp);
+}
 
 /**
  *	init_sd - entry point for this driver (both when built in or when