1 files changed, 91 insertions, 0 deletions
diff --git a/arch/x86/include/asm/vm86.h b/arch/x86/include/asm/vm86.h
new file mode 100644
index 000000000..9e8ac5073
--- /dev/null
+++ b/arch/x86/include/asm/vm86.h
@@ -0,0 +1,91 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#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 vm86 {
+	struct vm86plus_struct __user *user_vm86;
+	struct pt_regs regs32;
+	unsigned long veflags;
+	unsigned long veflags_mask;
+	unsigned long saved_sp0;
+
+	unsigned long flags;
+	unsigned long cpu_type;
+	struct revectored_struct int_revectored;
+	struct revectored_struct int21_revectored;
+	struct vm86plus_info_struct vm86plus;
+};
+
+#ifdef CONFIG_VM86
+
+void handle_vm86_fault(struct kernel_vm86_regs *, long);
+int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
+void save_v86_state(struct kernel_vm86_regs *, int);
+
+struct task_struct;
+
+#define free_vm86(t) do {				\
+	struct thread_struct *__t = (t);		\
+	if (__t->vm86 != NULL) {			\
+		kfree(__t->vm86);			\
+		__t->vm86 = NULL;			\
+	}						\
+} while (0)
+
+/*
+ * Support for VM86 programs to request interrupts for
+ * real mode hardware drivers:
+ */
+#define FIRST_VM86_IRQ		 3
+#define LAST_VM86_IRQ		15
+
+static inline int invalid_vm86_irq(int irq)
+{
+	return irq < FIRST_VM86_IRQ || irq > LAST_VM86_IRQ;
+}
+
+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;
+}
+
+static inline void save_v86_state(struct kernel_vm86_regs *a, int b) { }
+
+#define free_vm86(t) do { } while(0)
+
+#endif /* CONFIG_VM86 */
+
+#endif /* _ASM_X86_VM86_H */