[PATCH] md: make md work a bit better with devfs

- set ->devfs_name
- create initial devfs names slightly differently so
  as not to conflict
- re-read partition table when an array is assembled at boot
  time - not sure why this is needed, but it is.
Signed-off-by: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/md/md.c

@@ -1473,10 +1473,13 @@ static struct kobject *md_probe(dev_t dev, int *part, void *data)
 	}
 	disk->major = MAJOR(dev);
 	disk->first_minor = unit << shift;
-	if (partitioned)
+	if (partitioned) {
 		sprintf(disk->disk_name, "md_d%d", unit);
-	else
+		sprintf(disk->devfs_name, "md/d%d", unit);
+	} else {
 		sprintf(disk->disk_name, "md%d", unit);
+		sprintf(disk->devfs_name, "md/%d", unit);
+	}
 	disk->fops = &md_fops;
 	disk->private_data = mddev;
 	disk->queue = mddev->queue;
@@ -3659,7 +3662,7 @@ int __init md_init(void)
 	for (minor=0; minor < MAX_MD_DEVS; ++minor)
 		devfs_mk_bdev(MKDEV(mdp_major, minor<<MdpMinorShift),
 			      S_IFBLK|S_IRUSR|S_IWUSR,
-			      "md/d%d", minor);
+			      "md/mdp%d", minor);
 
 
 	register_reboot_notifier(&md_notifier);

init/do_mounts_md.c

@@ -232,6 +232,16 @@ static void __init md_setup_drive(void)
 			err = sys_ioctl(fd, RUN_ARRAY, 0);
 		if (err)
 			printk(KERN_WARNING "md: starting md%d failed\n", minor);
+		else {
+			/* reread the partition table.
+			 * I (neilb) and not sure why this is needed, but I cannot
+			 * boot a kernel with devfs compiled in from partitioned md
+			 * array without it
+			 */
+			sys_close(fd);
+			fd = sys_open(name, 0, 0);
+			sys_ioctl(fd, BLKRRPART, 0);
+		}
 		sys_close(fd);
 	}
 }