--- zzzz-none-000/linux-3.10.107/arch/um/os-Linux/file.c	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/arch/um/os-Linux/file.c	2021-02-04 17:41:59.000000000 +0000
@@ -13,6 +13,7 @@
 #include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/un.h>
+#include <sys/types.h>
 #include <os.h>
 
 static void copy_stat(struct uml_stat *dst, const struct stat64 *src)
@@ -237,6 +238,12 @@
 {
 	close(fd);
 }
+int os_fsync_file(int fd)
+{
+	if (fsync(fd) < 0)
+	    return -errno;
+	return 0;
+}
 
 int os_seek_file(int fd, unsigned long long offset)
 {
@@ -263,6 +270,15 @@
 
 	if (n < 0)
 		return -errno;
+	return n;
+}
+
+int os_sync_file(int fd)
+{
+	int n = fsync(fd);
+
+	if (n < 0)
+		return -errno;
 	return n;
 }