drbd: Allow online change of al-stripes and al-stripe-size
Allow to change the AL layout with an resize operation. For that
the reisze command gets two new fields: al_stripes and al_stripe_size.
In order to make the operation crash save:
1) Lock out all IO and MD-IO
2) Write the super block with MDF_PRIMARY_IND clear
3) write the bitmap to the new location (all zeros, since
we allow only while connected)
4) Initialize the new AL-area
5) Write the super block with the restored MDF_PRIMARY_IND.
6) Unfreeze all IO
Since the AL-layout has no influence on the protocol, this operation
needs to be beforemed on both sides of a resource (if intended).
Signed-off-by: Andreas Gruenbacher <agruen@linbit.com>
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/include/linux/drbd.h b/include/linux/drbd.h
index 1b4d4ee..de7d74a 100644
--- a/include/linux/drbd.h
+++ b/include/linux/drbd.h
@@ -177,7 +177,11 @@
ERR_NEED_APV_100 = 163,
ERR_NEED_ALLOW_TWO_PRI = 164,
ERR_MD_UNCLEAN = 165,
-
+ ERR_MD_LAYOUT_CONNECTED = 166,
+ ERR_MD_LAYOUT_TOO_BIG = 167,
+ ERR_MD_LAYOUT_TOO_SMALL = 168,
+ ERR_MD_LAYOUT_NO_FIT = 169,
+ ERR_IMPLICIT_SHRINK = 170,
/* insert new ones above this line */
AFTER_LAST_ERR_CODE
};