LXR linux/arch/x86/include/asm/vm86.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef _ASM_X86_VM86_H
   3#define _ASM_X86_VM86_H
   4
   5#include <asm/ptrace.h>
   6#include <uapi/asm/vm86.h>
   7
   8/*
   9 * This is the (kernel) stack-layout when we have done a "SAVE_ALL" from vm86
  10 * mode - the main change is that the old segment descriptors aren't
  11 * useful any more and are forced to be zero by the kernel (and the
  12 * hardware when a trap occurs), and the real segment descriptors are
  13 * at the end of the structure. Look at ptrace.h to see the "normal"
  14 * setup. For user space layout see 'struct vm86_regs' above.
  15 */
  16
  17struct kernel_vm86_regs {
  18/*
  19 * normal regs, with special meaning for the segment descriptors..
  20 */
  21        struct pt_regs pt;
  22/*
  23 * these are specific to v86 mode:
  24 */
  25        unsigned short es, __esh;
  26        unsigned short ds, __dsh;
  27        unsigned short fs, __fsh;
  28        unsigned short gs, __gsh;
  29};
  30
  31struct vm86 {
  32        struct vm86plus_struct __user *user_vm86;
  33        struct pt_regs regs32;
  34        unsigned long veflags;
  35        unsigned long veflags_mask;
  36        unsigned long saved_sp0;
  37
  38        unsigned long flags;
  39        unsigned long cpu_type;
  40        struct revectored_struct int_revectored;
  41        struct revectored_struct int21_revectored;
  42        struct vm86plus_info_struct vm86plus;
  43};
  44
  45#ifdef CONFIG_VM86
  46
  47void handle_vm86_fault(struct kernel_vm86_regs *, long);
  48int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
  49void save_v86_state(struct kernel_vm86_regs *, int);
  50
  51struct task_struct;
  52
  53#define free_vm86(t) do {                               \
  54        struct thread_struct *__t = (t);                \
  55        if (__t->vm86 != NULL) {                        \
  56                kfree(__t->vm86);                       \
  57                __t->vm86 = NULL;                       \
  58        }                                               \
  59} while (0)
  60
  61/*
  62 * Support for VM86 programs to request interrupts for
  63 * real mode hardware drivers:
  64 */
  65#define FIRST_VM86_IRQ           3
  66#define LAST_VM86_IRQ           15
  67
  68static inline int invalid_vm86_irq(int irq)
  69{
  70        return irq < FIRST_VM86_IRQ || irq > LAST_VM86_IRQ;
  71}
  72
  73void release_vm86_irqs(struct task_struct *);
  74
  75#else
  76
  77#define handle_vm86_fault(a, b)
  78#define release_vm86_irqs(a)
  79
  80static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c)
  81{
  82        return 0;
  83}
  84
  85static inline void save_v86_state(struct kernel_vm86_regs *a, int b) { }
  86
  87#define free_vm86(t) do { } while(0)
  88
  89#endif /* CONFIG_VM86 */
  90
  91#endif /* _ASM_X86_VM86_H */
  92