FIX: userspace should write entire buffer.

Huge oversight... Next is to try to regenerate the results, etc.

src/aarch64-linux-flush-dcache/userspace/writer_null.c

@@ -59,9 +59,13 @@ int main(int argc, char *argv[])
 	}
 
 	// Write to mmap-ed device
+	char *curr_buf = buf;
 	char to_write[4] = {0xca, 0xfe, 0xbe, 0xef};
-	for (size_t byte_offset = 0; byte_offset < WRITE_AMNT; byte_offset += 4)
-		memcpy(buf, to_write, 4);
+	while (curr_buf < (char *)buf + WRITE_AMNT) {
+		// eprintf("Writing to %p.\n", curr_buf);
+		memcpy(curr_buf, to_write, 4);
+		curr_buf += 4;
+	}
 
 	// Unmap device
 	munmap(buf, WRITE_AMNT);