1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2#ifndef _UAPI_ASM_X86_VM86_H
3#define _UAPI_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 /* _UAPI_ASM_X86_VM86_H */
131