dm snapshot: add allocated metadata to snapshot status

Add number of sectors used by metadata to the end of the snapshot's status
line.

Renamed dm_exception_store_type's 'fraction_full' to 'usage'.  Renamed
arguments to be clearer about what is being returned.  Also added
'metadata_sectors'.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index 92749696e359..366c8b1fca37 100644
--- a/drivers/md/dm-exception-store.h
+++ b/drivers/md/dm-exception-store.h
@@ -86,9 +86,9 @@ struct dm_exception_store_type {
         /*
          * Return how full the snapshot is.
          */
-        void (*fraction_full) (struct dm_exception_store *store,
-                               sector_t *numerator,
-                               sector_t *denominator);
+        void (*usage) (struct dm_exception_store *store,
+                       sector_t *total_sectors, sector_t *sectors_allocated,
+                       sector_t *metadata_sectors);
 
         /* For internal device-mapper use only. */
         struct list_head list;