[PATCH] i386: Update sys_vm86 to cope with changed pt_regs and %gs usage

sys_vm86 uses a struct kernel_vm86_regs, which is identical to pt_regs, but
adds an extra space for all the segment registers.  Previously this structure
was completely independent, so changes in pt_regs had to be reflected in
kernel_vm86_regs.  This changes just embeds pt_regs in kernel_vm86_regs, and
makes the appropriate changes to vm86.c to deal with the new naming.

Also, since %gs is dealt with differently in the kernel, this change adjusts
vm86.c to reflect this.

While making these changes, I also cleaned up some frankly bizarre code which
was added when auditing was added to sys_vm86.
Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Cc: Chuck Ebbert <76306.1226@compuserve.com>
Cc: Zachary Amsden <zach@vmware.com>
Cc: Jan Beulich <jbeulich@novell.com>
Cc: Andi Kleen <ak@suse.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>

include/asm-i386/vm86.h

@@ -145,26 +145,13 @@ struct vm86plus_struct {
  * at the end of the structure. Look at ptrace.h to see the "normal"
  * setup. For user space layout see 'struct vm86_regs' above.
  */
+#include <asm/ptrace.h>
 
 struct kernel_vm86_regs {
 /*
  * normal regs, with special meaning for the segment descriptors..
  */
-	long ebx;
-	long ecx;
-	long edx;
-	long esi;
-	long edi;
-	long ebp;
-	long eax;
-	long __null_ds;
-	long __null_es;
-	long orig_eax;
-	long eip;
-	unsigned short cs, __csh;
-	long eflags;
-	long esp;
-	unsigned short ss, __ssh;
+	struct pt_regs pt;
 /*
  * these are specific to v86 mode:
  */