441  * and @ancestor hasn't been overwritten in @seen
444  * @seen:	list of snapshot ids already seen at current position
450 static bool key_visible_in_snapshot(struct bch_fs *c, struct snapshots_seen *seen,  in key_visible_in_snapshot()  argument
459 	/* @ancestor should be the snapshot most recently added to @seen */  in key_visible_in_snapshot()
460 	EBUG_ON(ancestor != seen->pos.snapshot);  in key_visible_in_snapshot()
461 	EBUG_ON(ancestor != seen->ids.data[seen->ids.nr - 1].equiv);  in key_visible_in_snapshot()
471 	 * we've seen a key that overwrote @ancestor - i.e. also a descendent of  in key_visible_in_snapshot()
479 	for (i = seen->ids.nr - 2;  in key_visible_in_snapshot()
480 	     i >= 0 && seen->ids.data[i].equiv >= id;  in key_visible_in_snapshot()
482 		if (bch2_snapshot_is_ancestor(c, id, seen->ids.data[i].equiv))  in key_visible_in_snapshot()
494  * @s:		list of snapshot IDs already seen at @src
1048 	struct snapshots_seen	seen;  member
1059 		snapshots_seen_exit(&i->seen);  in extent_ends_reset()
1076 			  struct snapshots_seen *seen,  in extent_ends_at()  argument
1082 		.seen		= *seen,  in extent_ends_at()
1085 	n.seen.ids.data = kmemdup(seen->ids.data,  in extent_ends_at()
1086 			      sizeof(seen->ids.data[0]) * seen->ids.size,  in extent_ends_at()
1088 	if (!n.seen.ids.data)  in extent_ends_at()
1093 			snapshots_seen_exit(&i->seen);  in extent_ends_at()
1222 			      struct snapshots_seen *seen,  in check_overlapping_extents()  argument
1244 				  k.k->p.snapshot, seen,  in check_overlapping_extents()
1245 				  i->snapshot, &i->seen))  in check_overlapping_extents()
1252 						&i->seen,  in check_overlapping_extents()
1258 	ret = extent_ends_at(c, extent_ends, seen, k);  in check_overlapping_extents()