remove BlockstoreMover interface

we decided it's premature

blockstore/blockstore.go

@@ -35,22 +35,6 @@ type BlockstoreIterator interface {
 	ForEachKey(func(cid.Cid) error) error
 }
 
-// BlockstoreMover is a trait for movable blockstores
-type BlockstoreMover interface {
-	// Moves the blockstore to path, and creates a symlink from the current path
-	// to the new path; the old blockstore is deleted.
-	// If path is empty, then a new path adjacent to the current path is created
-	// automatically.
-	// If the filter function is not nil, then the move filters and moves only
-	// objects whose cid satisfyn the filter.
-	//
-	// The blockstore must accept new writes during the move and ensure that these
-	// are persisted to the new blockstore; if a failure occurs aboring the move,
-	// then they must be peristed to the old blockstore.
-	// In short, the blockstore must not lose data from new writes during the move.
-	MoveTo(path string, filter func(cid.Cid) bool) error
-}
-
 // BlockstoreGC is a trait for blockstores that support online garbage collection
 type BlockstoreGC interface {
 	CollectGarbage() error

blockstore/splitstore/splitstore_gc.go

@@ -5,41 +5,14 @@ import (
 	"time"
 
 	bstore "github.com/filecoin-project/lotus/blockstore"
-	cid "github.com/ipfs/go-cid"
 )
 
 func (s *SplitStore) gcHotstore() {
-	// we only perform moving gc every 20 compactions (about once a week) as it can take a while
-	if s.compactionIndex%20 == 0 {
-		if err := s.gcBlockstoreMoving(s.hot, "", nil); err != nil {
-			log.Warnf("error moving hotstore: %s", err)
-			// fallthrough to online gc
-		} else {
-			return
-		}
-	}
-
 	if err := s.gcBlockstoreOnline(s.hot); err != nil {
 		log.Warnf("error garbage collecting hostore: %s", err)
 	}
 }
 
-func (s *SplitStore) gcBlockstoreMoving(b bstore.Blockstore, path string, filter func(cid.Cid) bool) error {
-	if mover, ok := b.(bstore.BlockstoreMover); ok {
-		log.Info("moving blockstore")
-		startMove := time.Now()
-
-		if err := mover.MoveTo(path, filter); err != nil {
-			return err
-		}
-
-		log.Infow("moving hotstore done", "took", time.Since(startMove))
-		return nil
-	}
-
-	return fmt.Errorf("blockstore doesn't support moving: %T", b)
-}
-
 func (s *SplitStore) gcBlockstoreOnline(b bstore.Blockstore) error {
 	if gc, ok := b.(bstore.BlockstoreGC); ok {
 		log.Info("garbage collecting blockstore")