1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _ASM_X86_VM86_H
3#define _ASM_X86_VM86_H
4
5/*
6 * I'm guessing at the VIF/VIP flag usage, but hope that this is how
7 * the Pentium uses them. Linux will return from vm86 mode when both
8 * VIF and VIP is set.
9 *
10 * On a Pentium, we could probably optimize the virtual flags directly
11 * in the eflags register instead of doing it "by hand" in vflags...
12 *
13 * Linus
14 */
15
16#include <asm/processor-flags.h>
17
18#define BIOSSEG 0x0f000
19
20#define CPU_086 0
21#define CPU_186 1
22#define CPU_286 2
23#define CPU_386 3
24#define CPU_486 4
25#define CPU_586 5
26
27/*
28 * Return values for the 'vm86()' system call
29 */
30#define VM86_TYPE(retval) ((retval) & 0xff)
31#define VM86_ARG(retval) ((retval) >> 8)
32
33#define VM86_SIGNAL 0 /* return due to signal */
34#define VM86_UNKNOWN 1 /* unhandled GP fault
35 - IO-instruction or similar */
36#define VM86_INTx 2 /* int3/int x instruction (ARG = x) */
37#define VM86_STI 3 /* sti/popf/iret instruction enabled
38 virtual interrupts */
39
40/*
41 * Additional return values when invoking new vm86()
42 */
43#define VM86_PICRETURN 4 /* return due to pending PIC request */
44#define VM86_TRAP 6 /* return due to DOS-debugger request */
45
46/*
47 * function codes when invoking new vm86()
48 */
49#define VM86_PLUS_INSTALL_CHECK 0
50#define VM86_ENTER 1
51#define VM86_ENTER_NO_BYPASS 2
52#define VM86_REQUEST_IRQ 3
53#define VM86_FREE_IRQ 4
54#define VM86_GET_IRQ_BITS 5
55#define VM86_GET_AND_RESET_IRQ 6
56
57/*
58 * This is the stack-layout seen by the user space program when we have
59 * done a translation of "SAVE_ALL" from vm86 mode. The real kernel layout
60 * is 'kernel_vm86_regs' (see below).
61 */
62
63struct vm86_regs {
64/*
65 * normal regs, with special meaning for the segment descriptors..
66 */
67 long ebx;
68 long ecx;
69 long edx;
70 long esi;
71 long edi;
72 long ebp;
73 long eax;
74 long __null_ds;
75 long __null_es;
76 long __null_fs;
77 long __null_gs;
78 long orig_eax;
79 long eip;
80 unsigned short cs, __csh;
81 long eflags;
82 long esp;
83 unsigned short ss, __ssh;
84/*
85 * these are specific to v86 mode:
86 */
87 unsigned short es, __esh;
88 unsigned short ds, __dsh;
89 unsigned short fs, __fsh;
90 unsigned short gs, __gsh;
91};
92
93struct revectored_struct {
94 unsigned long __map[8]; /* 256 bits */
95};
96
97struct vm86_struct {
98 struct vm86_regs regs;
99 unsigned long flags;
100 unsigned long screen_bitmap; /* unused, preserved by vm86() */
101 unsigned long cpu_type;
102 struct revectored_struct int_revectored;
103 struct revectored_struct int21_revectored;
104};
105
106/*
107 * flags masks
108 */
109#define VM86_SCREEN_BITMAP 0x0001 /* no longer supported */
110
111struct vm86plus_info_struct {
112 unsigned long force_return_for_pic:1;
113 unsigned long vm86dbg_active:1; /* for debugger */
114 unsigned long vm86dbg_TFpendig:1; /* for debugger */
115 unsigned long unused:28;
116 unsigned long is_vm86pus:1; /* for vm86 internal use */
117 unsigned char vm86dbg_intxxtab[32]; /* for debugger */
118};
119struct vm86plus_struct {
120 struct vm86_regs regs;
121 unsigned long flags;
122 unsigned long screen_bitmap;
123 unsigned long cpu_type;
124 struct revectored_struct int_revectored;
125 struct revectored_struct int21_revectored;
126 struct vm86plus_info_struct vm86plus;
127};
128
129
130#endif /* _ASM_X86_VM86_H */