[PATCH] md: simplify checking of available size when resizing an array

When "mdadm --grow --size=xxx" is used to resize an array (use more or less of
each device), we check the new siza against the available space in each
device.

We already have that number recorded in rdev->size, so calculating it is
pointless (and wrong in one obscure case).

Signed-off-by: Neil Brown <neilb@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 c40ce9f9cc9bac881c4a737a7a85e05fd9e13897..50ab4a936e30a3e405e314f648049c518446e018 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -4045,11 +4045,8 @@ static int update_size(mddev_t *mddev, unsigned long size)
                return -EBUSY;
        ITERATE_RDEV(mddev,rdev,tmp) {
                sector_t avail;
-               if (rdev->sb_offset > rdev->data_offset)
-                       avail = (rdev->sb_offset*2) - rdev->data_offset;
-               else
-                       avail = get_capacity(rdev->bdev->bd_disk)
-                               - rdev->data_offset;
+               avail = rdev->size * 2;
+
                if (fit && (size == 0 || size > avail/2))
                        size = avail/2;
                if (avail < ((sector_t)size << 1))