diff --git a/sys/dev/drm/include/linux/file.h b/sys/dev/drm/include/linux/file.h
--- a/sys/dev/drm/include/linux/file.h
+++ b/sys/dev/drm/include/linux/file.h
@@ -33,6 +33,7 @@
 
 #ifdef __DragonFly__
 #include <sys/filedesc.h>
+#include <sys/kern_syscall.h>
 #endif
 
 static inline int
@@ -64,7 +65,10 @@
 static inline void
 put_unused_fd(unsigned int fd)
 {
-	kprintf("put_unused_fd(): not implemented\n");
+	struct lwp *lp = curthread->td_lwp;
+
+	if (lp != NULL && fd >= 0)
+		kern_close(fd);
 }
 
 #endif	/* _LINUX_FILE_H_ */