[deliverable/linux.git] / arch / x86 / include / asm / vm86.h

#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 kernel_vm86_struct {
	struct kernel_vm86_regs regs;
/*
 * the below part remains on the kernel stack while we are in VM86 mode.
 * 'tss.esp0' then contains the address of VM86_TSS_ESP0 below, and when we
 * get forced back from VM86, the CPU and "SAVE_ALL" will restore the above
 * 'struct kernel_vm86_regs' with the then actual values.
 * Therefore, pt_regs in fact points to a complete 'kernel_vm86_struct'
 * in kernelspace, hence we need not reget the data from userspace.
 */
#define VM86_TSS_ESP0 flags
	unsigned long flags;
	unsigned long screen_bitmap;
	unsigned long cpu_type;
	struct revectored_struct int_revectored;
	struct revectored_struct int21_revectored;
	struct vm86plus_info_struct vm86plus;
	struct pt_regs *regs32;   /* here we save the pointer to the old regs */
/*
 * The below is not part of the structure, but the stack layout continues
 * this way. In front of 'return-eip' may be some data, depending on
 * compilation, so we don't rely on this and save the pointer to 'oldregs'
 * in 'regs32' above.
 * However, with GCC-2.7.2 and the current CFLAGS you see exactly this:

	long return-eip;        from call to vm86()
	struct pt_regs oldregs;  user space registers as saved by syscall
 */
};

struct vm86 {
	struct vm86plus_struct __user *vm86_info;
	unsigned long screen_bitmap;
	unsigned long v86flags;
	unsigned long v86mask;
	unsigned long saved_sp0;
};

#ifdef CONFIG_VM86

void handle_vm86_fault(struct kernel_vm86_regs *, long);
int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
struct pt_regs *save_v86_state(struct kernel_vm86_regs *);

struct task_struct;
void release_vm86_irqs(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)

#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;
}

#define free_vm86(t) do { } while(0)

#endif /* CONFIG_VM86 */

#endif /* _ASM_X86_VM86_H */
Commit	Line	Data
1965aae3 PA	1	#ifndef _ASM_X86_VM86_H
1965aae3 PA	2	#define _ASM_X86_VM86_H
1da177e4	3
6330a30a	4	#include <asm/ptrace.h>
af170c50	5	#include <uapi/asm/vm86.h>
9831bfb2	6
1da177e4 LT	7	/*
	8	* This is the (kernel) stack-layout when we have done a "SAVE_ALL" from vm86
	9	* mode - the main change is that the old segment descriptors aren't
	10	* useful any more and are forced to be zero by the kernel (and the
	11	* hardware when a trap occurs), and the real segment descriptors are
	12	* at the end of the structure. Look at ptrace.h to see the "normal"
	13	* setup. For user space layout see 'struct vm86_regs' above.
	14	*/
	15
	16	struct kernel_vm86_regs {
	17	/*
	18	* normal regs, with special meaning for the segment descriptors..
	19	*/
49d26b6e	20	struct pt_regs pt;
1da177e4 LT	21	/*
	22	* these are specific to v86 mode:
	23	*/
	24	unsigned short es, __esh;
	25	unsigned short ds, __dsh;
	26	unsigned short fs, __fsh;
	27	unsigned short gs, __gsh;
	28	};
	29
	30	struct kernel_vm86_struct {
	31	struct kernel_vm86_regs regs;
	32	/*
	33	* the below part remains on the kernel stack while we are in VM86 mode.
	34	* 'tss.esp0' then contains the address of VM86_TSS_ESP0 below, and when we
	35	* get forced back from VM86, the CPU and "SAVE_ALL" will restore the above
	36	* 'struct kernel_vm86_regs' with the then actual values.
	37	* Therefore, pt_regs in fact points to a complete 'kernel_vm86_struct'
	38	* in kernelspace, hence we need not reget the data from userspace.
	39	*/
	40	#define VM86_TSS_ESP0 flags
	41	unsigned long flags;
	42	unsigned long screen_bitmap;
	43	unsigned long cpu_type;
	44	struct revectored_struct int_revectored;
	45	struct revectored_struct int21_revectored;
	46	struct vm86plus_info_struct vm86plus;
	47	struct pt_regs regs32; / here we save the pointer to the old regs */
	48	/*
	49	* The below is not part of the structure, but the stack layout continues
	50	* this way. In front of 'return-eip' may be some data, depending on
	51	* compilation, so we don't rely on this and save the pointer to 'oldregs'
	52	* in 'regs32' above.
	53	* However, with GCC-2.7.2 and the current CFLAGS you see exactly this:
	54
	55	long return-eip; from call to vm86()
	56	struct pt_regs oldregs; user space registers as saved by syscall
	57	*/
	58	};
	59
9fda6a06 BG	60	struct vm86 {
	61	struct vm86plus_struct __user *vm86_info;
	62	unsigned long screen_bitmap;
	63	unsigned long v86flags;
	64	unsigned long v86mask;
	65	unsigned long saved_sp0;
	66	};
	67
64ca9004 MM	68	#ifdef CONFIG_VM86
64ca9004 MM	69
1da177e4 LT	70	void handle_vm86_fault(struct kernel_vm86_regs *, long);
1da177e4 LT	71	int handle_vm86_trap(struct kernel_vm86_regs *, long, int);
e04f99c9	72	struct pt_regs save_v86_state(struct kernel_vm86_regs );
1da177e4	73
64ca9004 MM	74	struct task_struct;
	75	void release_vm86_irqs(struct task_struct *);
	76
9fda6a06 BG	77	#define free_vm86(t) do { \
	78	struct thread_struct *__t = (t); \
	79	if (__t->vm86 != NULL) { \
	80	kfree(__t->vm86); \
	81	__t->vm86 = NULL; \
	82	} \
	83	} while (0)
	84
64ca9004 MM	85	#else
	86
	87	#define handle_vm86_fault(a, b)
	88	#define release_vm86_irqs(a)
	89
9e8a935b JP	90	static inline int handle_vm86_trap(struct kernel_vm86_regs *a, long b, int c)
9e8a935b JP	91	{
64ca9004 MM	92	return 0;
	93	}
	94
9fda6a06 BG	95	#define free_vm86(t) do { } while(0)
9fda6a06 BG	96
64ca9004 MM	97	#endif /* CONFIG_VM86 */
64ca9004 MM	98
1965aae3	99	#endif /* _ASM_X86_VM86_H */