Driver Core: block: add nodename support for block drivers.

This adds support for block drivers to report their requested nodename
to userspace.  It also updates a number of block drivers to provide the
needed subdirectory and device name to be used for them.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Jan Blunck <jblunck@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 7cbd38d..45fc320 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -142,7 +142,7 @@
                                          * disks that can't be partitioned. */
 
 	char disk_name[DISK_NAME_LEN];	/* name of major driver */
-
+	char *(*nodename)(struct gendisk *gd);
 	/* Array of pointers to partitions indexed by partno.
 	 * Protected with matching bdev lock but stat and other
 	 * non-critical accesses use RCU.  Always access through