drivers/md/dm-snap.c

437  * snap_dest - a snapshot capable of receiving exception handover.
441  * Possible return values and states of snap_src and snap_dest.
444  *   2: snap_src, snap_dest  - waiting for handover
446  *   1: NULL, snap_dest - source got destroyed without handover
450 					struct dm_snapshot **snap_dest,
475 		} else if (snap_dest)
476 			*snap_dest = s;
491 	struct dm_snapshot *snap_src = NULL, *snap_dest = NULL;
495 	if ((__find_snapshots_sharing_cow(snap, &snap_src, &snap_dest,
497 	    snap_dest) {
1436 				  struct dm_snapshot *snap_dest)
1446 	u.table_swap = snap_dest->complete;
1447 	snap_dest->complete = snap_src->complete;
1450 	u.store_swap = snap_dest->store;
1451 	snap_dest->store = snap_src->store;
1452 	snap_dest->store->userspace_supports_overflow = u.store_swap->userspace_supports_overflow;
1455 	snap_dest->store->snap = snap_dest;
1458 	snap_dest->ti->max_io_len = snap_dest->store->chunk_size;
1459 	snap_dest->valid = snap_src->valid;
1460 	snap_dest->snapshot_overflowed = snap_src->snapshot_overflowed;
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)) {
1480 		down_write(&snap_dest->lock);
1481 		snap_dest->valid = 0;
1482 		up_write(&snap_dest->lock);
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) {
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) {
2264 		down_write_nested(&snap_dest->lock, SINGLE_DEPTH_NESTING);
2265 		__handover_exceptions(snap_src, snap_dest);
2266 		up_write(&snap_dest->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)