dm snapshot: support barriers (494b3ee7) · Commits · 戴 / test

drivers/md/dm-snap.c

+11 −0

Original line number	Diff line number	Diff line
		@@ -678,6 +678,7 @@ static int snapshot_ctr(struct dm_target ti, unsigned int argc, char *argv)

		ti->private = s;
		ti->split_io = s->store->chunk_size;
		ti->num_flush_requests = 1;

		return 0;

		@@ -1030,6 +1031,11 @@ static int snapshot_map(struct dm_target ti, struct bio bio,
		chunk_t chunk;
		struct dm_snap_pending_exception *pe = NULL;

		if (unlikely(bio_empty_barrier(bio))) {
		bio->bi_bdev = s->store->cow->bdev;
		return DM_MAPIO_REMAPPED;
		}

		chunk = sector_to_chunk(s->store, bio->bi_sector);

		/* Full snapshots are not usable */
		@@ -1338,6 +1344,8 @@ static int origin_ctr(struct dm_target ti, unsigned int argc, char *argv)
		}

		ti->private = dev;
		ti->num_flush_requests = 1;

		return 0;
		}

		@@ -1353,6 +1361,9 @@ static int origin_map(struct dm_target ti, struct bio bio,
		struct dm_dev *dev = ti->private;
		bio->bi_bdev = dev->bdev;

		if (unlikely(bio_empty_barrier(bio)))
		return DM_MAPIO_REMAPPED;

		/* Only tell snapshots if this is a write */
		return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : DM_MAPIO_REMAPPED;
		}