s3: keep object-lock buckets fully on the distributed lock

objectWriteOwner now returns "" for object-lock (WORM) buckets, so versioned
PutObject / copy / delete-marker no longer route them off the lock. Routed writes
serialize on the owner's per-path entry lock while retention-checked deletes use
the distributed lock, and those two locks don't serialize against each other; an
object-lock bucket that routed some writes and not others would split-brain on
the same object. Retention enforcement is gateway-side and not part of the
per-path-locked filer ops, so the whole bucket stays on the distributed lock and
remains internally consistent. The now-redundant gate is dropped from
routedObjectOwner.

weed/s3api/s3api_object_routed_write.go

@@ -28,9 +28,8 @@ func (s3a *S3ApiServer) routedObjectOwner(bucket, object string) (pb.ServerAddre
 	if enabled, err := s3a.isVersioningEnabled(bucket); err != nil || enabled {
 		return "", false
 	}
-	if locked, err := s3a.isObjectLockEnabled(bucket); err != nil || locked {
-		return "", false
-	}
+	// objectWriteOwner already excludes object-lock buckets (they stay fully on
+	// the distributed lock), returning "" for them.
 	owner := s3a.objectWriteOwner(bucket, object)
 	if owner == "" {
 		return "", false

weed/s3api/s3api_object_versioned_finalize.go

@@ -43,6 +43,15 @@ func (s3a *S3ApiServer) objectWriteOwner(bucket, object string) pb.ServerAddress
 	if s3a.objectWriteLockClient == nil {
 		return ""
 	}
+	// Object-lock (WORM) buckets keep ALL of their writes on the distributed
+	// lock. Retention enforcement is a gateway-side check that the per-path-locked
+	// filer ops don't perform, so routing only some of such a bucket's writes
+	// would split serialization between the entry lock and the distributed lock
+	// (they don't serialize against each other). Excluding the bucket entirely
+	// keeps it internally consistent.
+	if locked, err := s3a.isObjectLockEnabled(bucket); err != nil || locked {
+		return ""
+	}
 	return s3a.objectWriteLockClient.PrimaryForKey("s3.object.write:" + s3a.toFilerPath(bucket, object))
 }