@@ -1554,11 +1554,9 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
down_write(&s->lock);
- /* Full snapshots are not usable */
- if (!s->valid) {
- r = -EIO;
- goto out_unlock;
- }
+ /* Full merging snapshots are redirected to the origin */
+ if (!s->valid)
+ goto redirect_to_origin;
/* If the block is already remapped - use that */
e = dm_lookup_exception(&s->complete, chunk);
@@ -1581,6 +1579,7 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
goto out_unlock;
}
+ redirect_to_origin:
bio->bi_bdev = s->origin->bdev;
if (bio_rw(bio) == WRITE) {