While a read-only array doesn't not really need a bitmap, we should
not remove the bitmap when switching an array to read-only because
a/ There is no code to re-add the bitmap which switching to read-write,
b/ There is insufficient locking - the bitmap could be accessed while it is
being removed.
Cc: Reuben Farrelly <reuben-lkml@reub.net>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
978f946bb6