indir.patch

diff --git a/lib/db/keyer.go b/lib/db/keyer.go
index bbd2efa29..591d02230 100644
--- a/lib/db/keyer.go
+++ b/lib/db/keyer.go
@@ -325,6 +325,11 @@ func (k defaultKeyer) GenerateFolderMetaKey(key, folder []byte) (folderMetaKey,
 	return key, nil
 }
 
+type hashKey interface {
+	// Hash returns whatever hash is stored in the particular key implementing this.
+	Hash() []byte
+}
+
 type blockListKey []byte
 
 func (k defaultKeyer) GenerateBlockListKey(key []byte, hash []byte) blockListKey {
@@ -334,7 +339,7 @@ func (k defaultKeyer) GenerateBlockListKey(key []byte, hash []byte) blockListKey
 	return key
 }
 
-func (k blockListKey) BlocksHash() []byte {
+func (k blockListKey) Hash() []byte {
 	return k[keyPrefixLen:]
 }
 
@@ -347,7 +352,7 @@ func (k defaultKeyer) GenerateVersionKey(key []byte, hash []byte) versionKey {
 	return key
 }
 
-func (k versionKey) VersionHash() []byte {
+func (k versionKey) Hash() []byte {
 	return k[keyPrefixLen:]
 }
 
diff --git a/lib/db/lowlevel.go b/lib/db/lowlevel.go
index 1b8e041b6..6c44c2869 100644
--- a/lib/db/lowlevel.go
+++ b/lib/db/lowlevel.go
@@ -632,16 +632,8 @@ func (db *Lowlevel) gcIndirect(ctx context.Context) error {
 	if db.gcKeyCount > capacity {
 		capacity = db.gcKeyCount
 	}
-	blockFilter := blobloom.NewOptimized(blobloom.Config{
-		Capacity: uint64(capacity),
-		FPRate:   indirectGCBloomFalsePositiveRate,
-		MaxBits:  8 * indirectGCBloomMaxBytes,
-	})
-	versionFilter := blobloom.NewOptimized(blobloom.Config{
-		Capacity: uint64(capacity),
-		FPRate:   indirectGCBloomFalsePositiveRate,
-		MaxBits:  8 * indirectGCBloomMaxBytes,
-	})
+	blockFilter := newBloom(capacity)
+	versionFilter := newBloom(capacity)
 
 	// Iterate the FileInfos, unmarshal the block and version hashes and
 	// add them to the filter.
@@ -663,10 +655,10 @@ func (db *Lowlevel) gcIndirect(ctx context.Context) error {
 			return err
 		}
 		if len(hashes.BlocksHash) > 0 {
-			blockFilter.Add(bloomHash(hashes.BlocksHash))
+			blockFilter.Add(bloomHash(blockListKey(hashes.BlocksHash)))
 		}
 		if len(hashes.VersionHash) > 0 {
-			versionFilter.Add(bloomHash(hashes.VersionHash))
+			versionFilter.Add(bloomHash(versionKey(hashes.VersionHash)))
 		}
 	}
 	it.Release()
@@ -691,7 +683,7 @@ func (db *Lowlevel) gcIndirect(ctx context.Context) error {
 		}
 
 		key := blockListKey(it.Key())
-		if blockFilter.Has(bloomHash(key.BlocksHash())) {
+		if blockFilter.Has(bloomHash(key)) {
 			matchedBlocks++
 			continue
 		}
@@ -713,8 +705,14 @@ func (db *Lowlevel) gcIndirect(ctx context.Context) error {
 	}
 	matchedVersions := 0
 	for it.Next() {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+		}
+
 		key := versionKey(it.Key())
-		if versionFilter.Has(bloomHash(key.VersionHash())) {
+		if versionFilter.Has(bloomHash(key)) {
 			matchedVersions++
 			continue
 		}
@@ -740,10 +738,18 @@ func (db *Lowlevel) gcIndirect(ctx context.Context) error {
 	return db.Compact()
 }
 
+func newBloom(capacity int) *blobloom.Filter {
+	return blobloom.NewOptimized(blobloom.Config{
+		Capacity: uint64(capacity),
+		FPRate:   indirectGCBloomFalsePositiveRate,
+		MaxBits:  8 * indirectGCBloomMaxBytes,
+	})
+}
+
 // Hash function for the bloomfilter: first eight bytes of the SHA-256.
 // Big or little-endian makes no difference, as long as we're consistent.
-func bloomHash(key []byte) uint64 {
-	return binary.BigEndian.Uint64(key)
+func bloomHash(key hashKey) uint64 {
+	return binary.BigEndian.Uint64(key.Hash())
 }
 
 // CheckRepair checks folder metadata and sequences for miscellaneous errors.