Merge pull request topolvm#962 from topolvm/lvmd/handle-too-small-thi…

…n-pool

change: lvmd: make sure enough free space is available when creating LV snapshot

internal/lvmd/lvservice.go

@@ -242,6 +242,18 @@ func (s *lvService) CreateLVSnapshot(ctx context.Context, req *proto.CreateLVSna
 		return nil, status.Errorf(codes.OutOfRange, "requested size %v is smaller than source logical volume: %v", desiredSize, sizeOnCreation)
 	}
 
+	pool, err := vg.FindPool(ctx, dc.ThinPoolConfig.Name)
+	if err != nil {
+		logger.Error(err, "failed to get thinpool")
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+	tpu, err := pool.Free(ctx)
+	free := calcThinPoolFreeBytes(dc.ThinPoolConfig.OverprovisionRatio, tpu.SizeBytes, tpu.VirtualBytes)
+	if free < desiredSize {
+		logger.Error(err, "not enough space left on VG", "free", free, "desiredSize", desiredSize)
+		return nil, status.Errorf(codes.ResourceExhausted, "no enough space left on VG: free=%d, desiredSize=%d", free, desiredSize)
+	}
+
 	logger.Info(
 		"lvservice req",
 		"sizeOnCreation", sizeOnCreation,