From 5f6671a94a2359da3cbf6da500b34eea12a5f911 Mon Sep 17 00:00:00 2001
From: haad <haad@NetBSD.org>
Date: Thu, 13 Aug 2009 08:57:43 +0000
Subject: [PATCH] Allow undescribed, direct ioctls as used by Unix. This
 capability was removed in BSD, presumably because nothing used it any more.
 Third party system software written for Unix (like ZFS) requires this to work
 without significant modifications.

Ok supremeleader@
---
 sys/kern/sys_generic.c | 59 ++++++++++++++++++++++++------------------
 1 file changed, 34 insertions(+), 25 deletions(-)

diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c
index d3211f962046..75c7e7cc5292 100644
--- a/sys/kern/sys_generic.c
+++ b/sys/kern/sys_generic.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: sys_generic.c,v 1.123 2009/05/24 21:41:26 ad Exp $	*/
+/*	$NetBSD: sys_generic.c,v 1.124 2009/08/13 08:57:43 haad Exp $	*/
 
 /*-
  * Copyright (c) 2007, 2008, 2009 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_generic.c,v 1.123 2009/05/24 21:41:26 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_generic.c,v 1.124 2009/08/13 08:57:43 haad Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -565,31 +565,40 @@ sys_ioctl(struct lwp *l, const struct sys_ioctl_args *uap, register_t *retval)
 		goto out;
 	}
 	memp = NULL;
-	if (size > sizeof(stkbuf)) {
-		memp = kmem_alloc(size, KM_SLEEP);
-		data = memp;
-	} else
-		data = (void *)stkbuf;
-	if (com&IOC_IN) {
-		if (size) {
-			error = copyin(SCARG(uap, data), data, size);
-			if (error) {
-				if (memp)
-					kmem_free(memp, size);
-				goto out;
+	if ((com >> IOCPARM_SHIFT) == 0)  {
+		/* UNIX-style ioctl. */
+		data = SCARG(uap, data);
+	} else {
+		if (size > sizeof(stkbuf)) {
+			memp = kmem_alloc(size, KM_SLEEP);
+			data = memp;
+		} else {
+			data = (void *)stkbuf;
+		}
+		if (com&IOC_IN) {
+			if (size) {
+				error = copyin(SCARG(uap, data), data, size);
+				if (error) {
+					if (memp) {
+						kmem_free(memp, size);
+					}
+					goto out;
+				}
+				ktrgenio(SCARG(uap, fd), UIO_WRITE,
+				    SCARG(uap, data), size, 0);
+			} else {
+				*(void **)data = SCARG(uap, data);
 			}
-			ktrgenio(SCARG(uap, fd), UIO_WRITE, SCARG(uap, data),
-			    size, 0);
-		} else
+		} else if ((com&IOC_OUT) && size) {
+			/*
+			 * Zero the buffer so the user always
+			 * gets back something deterministic.
+			 */
+			memset(data, 0, size);
+		} else if (com&IOC_VOID) {
 			*(void **)data = SCARG(uap, data);
-	} else if ((com&IOC_OUT) && size)
-		/*
-		 * Zero the buffer so the user always
-		 * gets back something deterministic.
-		 */
-		memset(data, 0, size);
-	else if (com&IOC_VOID)
-		*(void **)data = SCARG(uap, data);
+		}
+	}
 
 	switch (com) {