+#include <sys/mman.h>
+#include <sched.h>
+
+char unload_heads_path[64];
+
+int set_unload_heads_path(char *device)
+{
+ char devname[64];
+
+ if (strlen(device) <= 5 || strncmp(device, "/dev/", 5) != 0)
+ return -EINVAL;
+ strncpy(devname, device + 5, sizeof(devname));
+
+ snprintf(unload_heads_path, sizeof(unload_heads_path),
+ "/sys/block/%s/device/unload_heads", devname);
+ return 0;
+}
+int valid_disk(void)
+{
+ int fd = open(unload_heads_path, O_RDONLY);
+ if (fd < 0) {
+ perror(unload_heads_path);
+ return 0;
+ }
+
+ close(fd);
+ return 1;
+}