1 files changed, 26 insertions, 1 deletions

diff --git a/arch/um/drivers/cow.h b/arch/um/drivers/cow.h
index 4fcbe8b1b77e..c54e20a3d21d 100644
--- a/arch/um/drivers/cow.h
+++ b/arch/um/drivers/cow.h
@@ -3,6 +3,26 @@
 
 #include <asm/types.h>
 
+#if defined(__KERNEL__)
+
+# include <asm/byteorder.h>
+
+# if defined(__BIG_ENDIAN)
+#       define ntohll(x) (x)
+#       define htonll(x) (x)
+# elif defined(__LITTLE_ENDIAN)
+#       define ntohll(x)  be64_to_cpu(x)
+#       define htonll(x)  cpu_to_be64(x)
+# else
+#       error "Could not determine byte order"
+# endif
+
+#else
+/* For the definition of ntohl, htonl and __BYTE_ORDER */
+#include <endian.h>
+#include <netinet/in.h>
+#if defined(__BYTE_ORDER)
+
 #if __BYTE_ORDER == __BIG_ENDIAN
 # define ntohll(x) (x)
 # define htonll(x) (x)
@@ -10,8 +30,13 @@
 # define ntohll(x)  bswap_64(x)
 # define htonll(x)  bswap_64(x)
 #else
-#error "__BYTE_ORDER not defined"
+# error "Could not determine byte order: __BYTE_ORDER uncorrectly defined"
+#endif
+
+#else  /* ! defined(__BYTE_ORDER) */
+#       error "Could not determine byte order: __BYTE_ORDER not defined"
 #endif
+#endif /* ! defined(__KERNEL__) */
 
 extern int init_cow_file(int fd, char *cow_file, char *backing_file,
                          int sectorsize, int alignment, int *bitmap_offset_out,