[PATCH] md: document sysfs usage of md, and make a couple of small refinements

Document in Documentation/md.txt the files that now appear in sysfs, and make
a couple of small refinements to exactly when 'level' and 'raid_disks' are
empty, to make it match the documentation.

Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 023aecd..adf960d 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1727,7 +1727,7 @@
 level_show(mddev_t *mddev, char *page)
 {
 	mdk_personality_t *p = mddev->pers;
-	if (p == NULL)
+	if (p == NULL && mddev->raid_disks == 0)
 		return 0;
 	if (mddev->level >= 0)
 		return sprintf(page, "RAID-%d\n", mddev->level);
@@ -1740,6 +1740,8 @@
 static ssize_t
 raid_disks_show(mddev_t *mddev, char *page)
 {
+	if (mddev->raid_disks == 0)
+		return 0;
 	return sprintf(page, "%d\n", mddev->raid_disks);
 }