#ifndef _ASM_X86_VM86_H
#define _ASM_X86_VM86_H


#include <asm/ptrace.h>
#include <uapi/asm/vm86.h>

/*
* This is the (kernel) stack-layout when we have done a "SAVE_ALL" from vm86
* mode - the main change is that the old segment descriptors aren't
* useful any more and are forced to be zero by the kernel (and the
* hardware when a trap occurs), and the real segment descriptors are
* at the end of the structure. Look at ptrace.h to see the "normal"
* setup. For user space layout see 'struct vm86_regs' above.
*/

struct kernel_vm86_regs {
/*
* normal regs, with special meaning for the segment descriptors..
*/
struct pt_regs pt;
/*
* these are specific to v86 mode:
*/
unsigned short es, __esh;
unsigned short ds, __dsh;
unsigned short fs, __fsh;
unsigned short gs, __gsh;
};

struct kernel_vm86_struct {
struct kernel_vm86_regs regs;
/*
* the below part remains on the kernel stack while we are in VM86 mode.
* 'tss.esp0' then contains the address of VM86_TSS_ESP0 below, and when we
* get forced back from VM86, the CPU and "SAVE_ALL" will restore the above
* 'struct kernel_vm86_regs' with the then actual values.
* Therefore, pt_regs in fact points to a complete 'kernel_vm86_struct'
* in kernelspace, hence we need not reget the data from userspace.
*/
#define VM86_TSS_ESP0 flags
unsigned long flags;
unsigned long screen_bitmap;
unsigned long cpu_type;
struct revectored_struct int_revectored;
struct revectored_struct int21_revectored;
struct vm86plus_info_struct vm86plus;
struct pt_regs *regs32; /* here we save the pointer to the old regs */
/*
* The below is not part of the structure, but the stack layout continues
* this way. In front of 'return-eip' may be some data, depending on
* compilation, so we don't rely on this and save the pointer to 'oldregs'
* in 'regs32' above.
* However, with GCC-2.7.2 and the current CFLAGS you see exactly this:

long return-eip; from call to vm86()
struct pt_regs oldregs; user space registers as saved by syscall
*/
};

#ifdef CONFIG_VM86

void handle_vm86_fault(struct kernel_vm86_regs *, long);
int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
struct pt_regs *save_v86_state(struct kernel_vm86_regs *);

struct task_struct;
void release_vm86_irqs(struct task_struct *);

#else

#define handle_vm86_fault(a, b)
#define release_vm86_irqs(a)

static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c)
{
return 0;
}

#endif /* CONFIG_VM86 */

#endif /* _ASM_X86_VM86_H */