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, 9 insertions, 6 deletions

diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c
index 267801b34ff6..245a50c7337e 100644
--- a/drivers/md/dm-snap-transient.c
+++ b/drivers/md/dm-snap-transient.c
@@ -59,11 +59,14 @@ static void transient_commit_exception(struct dm_exception_store *store,
         callback(callback_context, 1);
 }
 
-static void transient_fraction_full(struct dm_exception_store *store,
-                                    sector_t *numerator, sector_t *denominator)
+static void transient_usage(struct dm_exception_store *store,
+                            sector_t *total_sectors,
+                            sector_t *sectors_allocated,
+                            sector_t *metadata_sectors)
 {
-        *numerator = ((struct transient_c *) store->context)->next_free;
-        *denominator = get_dev_size(store->cow->bdev);
+        *sectors_allocated = ((struct transient_c *) store->context)->next_free;
+        *total_sectors = get_dev_size(store->cow->bdev);
+        *metadata_sectors = 0;
 }
 
 static int transient_ctr(struct dm_exception_store *store,
@@ -106,7 +109,7 @@ static struct dm_exception_store_type _transient_type = {
         .read_metadata = transient_read_metadata,
         .prepare_exception = transient_prepare_exception,
         .commit_exception = transient_commit_exception,
-        .fraction_full = transient_fraction_full,
+        .usage = transient_usage,
         .status = transient_status,
 };
 
@@ -118,7 +121,7 @@ static struct dm_exception_store_type _transient_compat_type = {
         .read_metadata = transient_read_metadata,
         .prepare_exception = transient_prepare_exception,
         .commit_exception = transient_commit_exception,
-        .fraction_full = transient_fraction_full,
+        .usage = transient_usage,
         .status = transient_status,
 };