extern int read_cow_header(int (*reader)(__u64, char *, int, void *),
void *arg, __u32 *version_out,
char **backing_file_out, time_t *mtime_out,
- __u64 *size_out, int *sectorsize_out,
+ unsigned long long *size_out, int *sectorsize_out,
__u32 *align_out, int *bitmap_offset_out);
extern int write_cow_header(char *cow_file, int fd, char *backing_file,