From: Mike Snitzer Keep track of whether or not the device is suspended within the snapshot target module, the same as we do in dm-raid1. We will use this later to enforce the correct sequence of ioctls to transfer the in-core exceptions from a snapshot target instance in one table to a replacement one capable of merging them back into the origin. Signed-off-by: Mike Snitzer Signed-off-by: Alasdair G Kergon --- drivers/md/dm-snap.c | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) Index: linux-2.6.32/drivers/md/dm-snap.c =================================================================== --- linux-2.6.32.orig/drivers/md/dm-snap.c +++ linux-2.6.32/drivers/md/dm-snap.c @@ -72,6 +72,9 @@ struct dm_snapshot { /* Origin writes don't trigger exceptions until this is set */ int active; + /* Whether or not owning mapped_device is suspended */ + int suspended; + mempool_t *pending_pool; atomic_t pending_exceptions_count; @@ -656,6 +659,7 @@ static int snapshot_ctr(struct dm_target s->ti = ti; s->valid = 1; s->active = 0; + s->suspended = 0; atomic_set(&s->pending_exceptions_count, 0); init_rwsem(&s->lock); spin_lock_init(&s->pe_lock); @@ -1175,12 +1179,22 @@ static int snapshot_end_io(struct dm_tar return 0; } +static void snapshot_postsuspend(struct dm_target *ti) +{ + struct dm_snapshot *s = ti->private; + + down_write(&s->lock); + s->suspended = 1; + up_write(&s->lock); +} + static void snapshot_resume(struct dm_target *ti) { struct dm_snapshot *s = ti->private; down_write(&s->lock); s->active = 1; + s->suspended = 0; up_write(&s->lock); } @@ -1489,12 +1503,13 @@ static struct target_type origin_target static struct target_type snapshot_target = { .name = "snapshot", - .version = {1, 8, 0}, + .version = {1, 9, 0}, .module = THIS_MODULE, .ctr = snapshot_ctr, .dtr = snapshot_dtr, .map = snapshot_map, .end_io = snapshot_end_io, + .postsuspend = snapshot_postsuspend, .resume = snapshot_resume, .status = snapshot_status, .iterate_devices = snapshot_iterate_devices,