- Split ioctl() up into ioctl() and kern_ioctl(). The kern_ioctl() assumes

  that the 'data' pointer is already setup to point to a valid KVM buffer
  or contains the copied-in data from userland as appropriate (ioctl(2)
  still does this).  kern_ioctl() takes care of looking up a file pointer,
  implementing FIONCLEX and FIOCLEX, and calling fi_ioctl().
- Use kern_ioctl() to implement xenix_rdchk() instead of using the stackgap
  and mark xenix_rdchk() MPSAFE.

2 files changed, 8 insertions, 11 deletions

diff --git a/sys/i386/ibcs2/ibcs2_xenix.c b/sys/i386/ibcs2/ibcs2_xenix.c
index faa9d7c..e3fbc04 100644
--- a/sys/i386/ibcs2/ibcs2_xenix.c
+++ b/sys/i386/ibcs2/ibcs2_xenix.c
@@ -84,18 +84,15 @@ xenix_rdchk(td, uap)
 	struct thread *td;
 	struct xenix_rdchk_args *uap;
 {
-	int error;
-	struct ioctl_args sa;
-	caddr_t sg = stackgap_init();
+	int data, error;
 
 	DPRINTF(("IBCS2: 'xenix rdchk'\n"));
-	sa.fd = uap->fd;
-	sa.com = FIONREAD;
-	sa.data = stackgap_alloc(&sg, sizeof(int));
-	if ((error = ioctl(td, &sa)) != 0)
-		return error;
-	td->td_retval[0] = (*((int*)sa.data)) ? 1 : 0;
-	return 0;
+	
+	error = kern_ioctl(td, uap->fd, FIONREAD, (caddr_t)&data);
+	if (error)
+		return (error);
+	td->td_retval[0] = data ? 1 : 0;
+	return (0);
 }
 
 int
diff --git a/sys/i386/ibcs2/syscalls.xenix b/sys/i386/ibcs2/syscalls.xenix
index 8b9b84a..2fc1838 100644
--- a/sys/i386/ibcs2/syscalls.xenix
+++ b/sys/i386/ibcs2/syscalls.xenix
@@ -14,7 +14,7 @@
 4	AUE_NULL	UNIMPL	xenix_sigsem
 5	AUE_NULL	UNIMPL	xenix_waitsem
 6	AUE_NULL	UNIMPL	xenix_nbwaitsem
-7	AUE_NULL	STD	{ int xenix_rdchk(int fd); }
+7	AUE_NULL	MSTD	{ int xenix_rdchk(int fd); }
 8	AUE_NULL	UNIMPL	nosys
 9	AUE_NULL	UNIMPL	nosys
 10	AUE_FTRUNCATE	MSTD	{ int xenix_chsize(int fd, long size); }