dm: keep old table until after resume succeeded
When swapping a new table into place, retain the old table until
its replacement is in place.
An old check for an empty table is removed because this is enforced
in populate_table().
__unbind() becomes redundant when followed by __bind().
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index fc16a35..b9c6c8c 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -295,8 +295,10 @@
/*
* The device must be suspended before calling this method.
+ * Returns the previous table, which the caller must destroy.
*/
-int dm_swap_table(struct mapped_device *md, struct dm_table *t);
+struct dm_table *dm_swap_table(struct mapped_device *md,
+ struct dm_table *t);
/*
* A wrapper around vmalloc.