[PATCH] s390: dasd open counter

The open_count is increased for every opener, that includes the blkdev_get in
dasd_scan_partitions.  This tampers the open_count in BIODASDINFO.  Hide the
internal open from user-space.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/s390/block/dasd_ioctl.c

@@ -421,8 +421,15 @@ dasd_ioctl_information(struct block_device *bdev, int no, long args)
 	dasd_info->cu_model = cdev->id.cu_model;
 	dasd_info->dev_type = cdev->id.dev_type;
 	dasd_info->dev_model = cdev->id.dev_model;
-	dasd_info->open_count = atomic_read(&device->open_count);
 	dasd_info->status = device->state;
+	/*
+	 * The open_count is increased for every opener, that includes
+	 * the blkdev_get in dasd_scan_partitions.
+	 * This must be hidden from user-space.
+	 */
+	dasd_info->open_count = atomic_read(&device->open_count);
+	if (!device->bdev)
+		dasd_info->open_count++;
 
 	/*
 	 * check if device is really formatted