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>
diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index 9274969..366c8b1 100644
--- a/drivers/md/dm-exception-store.h
+++ b/drivers/md/dm-exception-store.h
@@ -86,9 +86,9 @@
/*
* 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;
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index 24b8acd..767065f 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -489,11 +489,22 @@
return (struct pstore *) store->context;
}
-static void persistent_fraction_full(struct dm_exception_store *store,
- sector_t *numerator, sector_t *denominator)
+static void persistent_usage(struct dm_exception_store *store,
+ sector_t *total_sectors,
+ sector_t *sectors_allocated,
+ sector_t *metadata_sectors)
{
- *numerator = get_info(store)->next_free * store->chunk_size;
- *denominator = get_dev_size(store->cow->bdev);
+ struct pstore *ps = get_info(store);
+
+ *sectors_allocated = ps->next_free * store->chunk_size;
+ *total_sectors = get_dev_size(store->cow->bdev);
+
+ /*
+ * First chunk is the fixed header.
+ * Then there are (ps->current_area + 1) metadata chunks, each one
+ * separated from the next by ps->exceptions_per_area data chunks.
+ */
+ *metadata_sectors = (ps->current_area + 2) * store->chunk_size;
}
static void persistent_dtr(struct dm_exception_store *store)
@@ -738,7 +749,7 @@
.prepare_exception = persistent_prepare_exception,
.commit_exception = persistent_commit_exception,
.drop_snapshot = persistent_drop_snapshot,
- .fraction_full = persistent_fraction_full,
+ .usage = persistent_usage,
.status = persistent_status,
};
@@ -751,7 +762,7 @@
.prepare_exception = persistent_prepare_exception,
.commit_exception = persistent_commit_exception,
.drop_snapshot = persistent_drop_snapshot,
- .fraction_full = persistent_fraction_full,
+ .usage = persistent_usage,
.status = persistent_status,
};
diff --git a/drivers/md/dm-snap-transient.c b/drivers/md/dm-snap-transient.c
index 267801b..245a50c 100644
--- a/drivers/md/dm-snap-transient.c
+++ b/drivers/md/dm-snap-transient.c
@@ -59,11 +59,14 @@
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 @@
.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 @@
.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,
};
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index cb4c2c3..8bd77cbd 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1174,14 +1174,17 @@
if (!snap->valid)
DMEMIT("Invalid");
else {
- if (snap->store->type->fraction_full) {
- sector_t numerator, denominator;
- snap->store->type->fraction_full(snap->store,
- &numerator,
- &denominator);
- DMEMIT("%llu/%llu",
- (unsigned long long)numerator,
- (unsigned long long)denominator);
+ if (snap->store->type->usage) {
+ sector_t total_sectors, sectors_allocated,
+ metadata_sectors;
+ snap->store->type->usage(snap->store,
+ &total_sectors,
+ §ors_allocated,
+ &metadata_sectors);
+ DMEMIT("%llu/%llu %llu",
+ (unsigned long long)sectors_allocated,
+ (unsigned long long)total_sectors,
+ (unsigned long long)metadata_sectors);
}
else
DMEMIT("Unknown");
@@ -1462,7 +1465,7 @@
static struct target_type snapshot_target = {
.name = "snapshot",
- .version = {1, 7, 0},
+ .version = {1, 8, 0},
.module = THIS_MODULE,
.ctr = snapshot_ctr,
.dtr = snapshot_dtr,
