drivers/md/dm-snap.c

436  * snap_src - a snapshot suitable for use as a source of exception handover
441  * Possible return values and states of snap_src and snap_dest.
443  *   1: snap_src, NULL - normal snapshot
444  *   2: snap_src, snap_dest  - waiting for handover
445  *   2: snap_src, NULL - handed over, waiting for old to be deleted
449 					struct dm_snapshot **snap_src,
473 			if (snap_src)
474 				*snap_src = s;
491 	struct dm_snapshot *snap_src = NULL, *snap_dest = NULL;
495 	if ((__find_snapshots_sharing_cow(snap, &snap_src, &snap_dest,
503 	 * If no snap_src was found, snap cannot become a handover
506 	if (!snap_src)
523 	if (!snap_src->store->type->prepare_merge ||
524 	    !snap_src->store->type->commit_merge) {
1435 static void __handover_exceptions(struct dm_snapshot *snap_src,
1447 	snap_dest->complete = snap_src->complete;
1448 	snap_src->complete = u.table_swap;
1451 	snap_dest->store = snap_src->store;
1453 	snap_src->store = u.store_swap;
1456 	snap_src->store->snap = snap_src;
1459 	snap_dest->valid = snap_src->valid;
1460 	snap_dest->snapshot_overflowed = snap_src->snapshot_overflowed;
1465 	snap_src->valid = 0;
1474 	struct dm_snapshot *snap_src = NULL, *snap_dest = NULL;
1478 	(void) __find_snapshots_sharing_cow(s, &snap_src, &snap_dest, NULL);
1479 	if (snap_src && snap_dest && (s == snap_src)) {
2204 	struct dm_snapshot *snap_src = NULL, *snap_dest = NULL;
2207 	(void) __find_snapshots_sharing_cow(s, &snap_src, &snap_dest, NULL);
2208 	if (snap_src && snap_dest) {
2209 		down_read(&snap_src->lock);
2210 		if (s == snap_src) {
2213 		} else if (!dm_suspended(snap_src->ti)) {
2217 		up_read(&snap_src->lock);
2227 	struct dm_snapshot *snap_src = NULL, *snap_dest = NULL, *snap_merging = NULL;
2261 	(void) __find_snapshots_sharing_cow(s, &snap_src, &snap_dest, NULL);
2262 	if (snap_src && snap_dest) {
2263 		down_write(&snap_src->lock);
2265 		__handover_exceptions(snap_src, snap_dest);
2267 		up_write(&snap_src->lock);
2403 		struct dm_snapshot *snap_src = NULL, *snap_dest = NULL;
2407 		(void) __find_snapshots_sharing_cow(snap, &snap_src, &snap_dest, NULL);
2408 		if (snap_src && snap_dest)
2409 			snap = snap_src;