xref: /openbmc/linux/arch/x86/include/asm/vm86.h (revision b24413180f5600bcb3bb70fbed5cf186b60864bd)
1*b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */
21965aae3SH. Peter Anvin #ifndef _ASM_X86_VM86_H
31965aae3SH. Peter Anvin #define _ASM_X86_VM86_H
4bb898558SAl Viro 
5bb898558SAl Viro #include <asm/ptrace.h>
6af170c50SDavid Howells #include <uapi/asm/vm86.h>
7bb898558SAl Viro 
8bb898558SAl Viro /*
9bb898558SAl Viro  * This is the (kernel) stack-layout when we have done a "SAVE_ALL" from vm86
10bb898558SAl Viro  * mode - the main change is that the old segment descriptors aren't
11bb898558SAl Viro  * useful any more and are forced to be zero by the kernel (and the
12bb898558SAl Viro  * hardware when a trap occurs), and the real segment descriptors are
13bb898558SAl Viro  * at the end of the structure. Look at ptrace.h to see the "normal"
14bb898558SAl Viro  * setup. For user space layout see 'struct vm86_regs' above.
15bb898558SAl Viro  */
16bb898558SAl Viro 
17bb898558SAl Viro struct kernel_vm86_regs {
18bb898558SAl Viro /*
19bb898558SAl Viro  * normal regs, with special meaning for the segment descriptors..
20bb898558SAl Viro  */
21bb898558SAl Viro 	struct pt_regs pt;
22bb898558SAl Viro /*
23bb898558SAl Viro  * these are specific to v86 mode:
24bb898558SAl Viro  */
25bb898558SAl Viro 	unsigned short es, __esh;
26bb898558SAl Viro 	unsigned short ds, __dsh;
27bb898558SAl Viro 	unsigned short fs, __fsh;
28bb898558SAl Viro 	unsigned short gs, __gsh;
29bb898558SAl Viro };
30bb898558SAl Viro 
319fda6a06SBrian Gerst struct vm86 {
3213426356SBrian Gerst 	struct vm86plus_struct __user *user_vm86;
335ed92a8aSBrian Gerst 	struct pt_regs regs32;
34decd275eSBrian Gerst 	unsigned long veflags;
35decd275eSBrian Gerst 	unsigned long veflags_mask;
369fda6a06SBrian Gerst 	unsigned long saved_sp0;
37d4ce0f26SBrian Gerst 
38d4ce0f26SBrian Gerst 	unsigned long flags;
39d4ce0f26SBrian Gerst 	unsigned long screen_bitmap;
40d4ce0f26SBrian Gerst 	unsigned long cpu_type;
41d4ce0f26SBrian Gerst 	struct revectored_struct int_revectored;
42d4ce0f26SBrian Gerst 	struct revectored_struct int21_revectored;
43d4ce0f26SBrian Gerst 	struct vm86plus_info_struct vm86plus;
449fda6a06SBrian Gerst };
459fda6a06SBrian Gerst 
46bb898558SAl Viro #ifdef CONFIG_VM86
47bb898558SAl Viro 
48bb898558SAl Viro void handle_vm86_fault(struct kernel_vm86_regs *, long);
49bb898558SAl Viro int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
505ed92a8aSBrian Gerst void save_v86_state(struct kernel_vm86_regs *, int);
51bb898558SAl Viro 
52bb898558SAl Viro struct task_struct;
53bb898558SAl Viro 
549fda6a06SBrian Gerst #define free_vm86(t) do {				\
559fda6a06SBrian Gerst 	struct thread_struct *__t = (t);		\
569fda6a06SBrian Gerst 	if (__t->vm86 != NULL) {			\
579fda6a06SBrian Gerst 		kfree(__t->vm86);			\
589fda6a06SBrian Gerst 		__t->vm86 = NULL;			\
599fda6a06SBrian Gerst 	}						\
609fda6a06SBrian Gerst } while (0)
619fda6a06SBrian Gerst 
62af3e565aSIngo Molnar /*
63af3e565aSIngo Molnar  * Support for VM86 programs to request interrupts for
64af3e565aSIngo Molnar  * real mode hardware drivers:
65af3e565aSIngo Molnar  */
66af3e565aSIngo Molnar #define FIRST_VM86_IRQ		 3
67af3e565aSIngo Molnar #define LAST_VM86_IRQ		15
68af3e565aSIngo Molnar 
69af3e565aSIngo Molnar static inline int invalid_vm86_irq(int irq)
70af3e565aSIngo Molnar {
71af3e565aSIngo Molnar 	return irq < FIRST_VM86_IRQ || irq > LAST_VM86_IRQ;
72af3e565aSIngo Molnar }
73af3e565aSIngo Molnar 
74af3e565aSIngo Molnar void release_vm86_irqs(struct task_struct *);
75af3e565aSIngo Molnar 
76bb898558SAl Viro #else
77bb898558SAl Viro 
78bb898558SAl Viro #define handle_vm86_fault(a, b)
79bb898558SAl Viro #define release_vm86_irqs(a)
80bb898558SAl Viro 
81bb898558SAl Viro static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c)
82bb898558SAl Viro {
83bb898558SAl Viro 	return 0;
84bb898558SAl Viro }
85bb898558SAl Viro 
865ed92a8aSBrian Gerst static inline void save_v86_state(struct kernel_vm86_regs *a, int b) { }
875ed92a8aSBrian Gerst 
889fda6a06SBrian Gerst #define free_vm86(t) do { } while(0)
899fda6a06SBrian Gerst 
90bb898558SAl Viro #endif /* CONFIG_VM86 */
91bb898558SAl Viro 
921965aae3SH. Peter Anvin #endif /* _ASM_X86_VM86_H */
93