OVS_GREP_IFELSE([$KSRC26/include/linux/types.h], [bool],
[OVS_DEFINE([HAVE_BOOL_TYPE])])
+ OVS_GREP_IFELSE([$KSRC26/include/linux/types.h], [__wsum],
+ [OVS_DEFINE([HAVE_CSUM_TYPES])])
OVS_GREP_IFELSE([$KSRC26/include/net/checksum.h], [csum_unfold],
[OVS_DEFINE([HAVE_CSUM_UNFOLD])])