md: tidy up set_bitmap_file
authorNeilBrown <neilb@suse.de>
Mon, 15 Dec 2014 01:57:00 +0000 (12:57 +1100)
committerNeilBrown <neilb@suse.de>
Thu, 5 Feb 2015 22:32:56 +0000 (09:32 +1100)
1/ delay setting mddev->bitmap_info.file until 'f' looks
   usable, so we don't have to unset it.
2/ Don't allow bitmap file to be set if bitmap_info.file
   is already set.

Signed-off-by: NeilBrown <neilb@suse.de>
drivers/md/md.c

diff --cc drivers/md/md.c
Simple merge