/*
* Things the lguest guest needs to know. Note: like all lguest interfaces,
* this is subject to wild and random change between versions.
*/
#ifndef _LINUX_LGUEST_H
#define _LINUX_LGUEST_H

#ifndef __ASSEMBLY__
#include <linux/time.h>
#include <asm/irq.h>
#include <asm/lguest_hcall.h>

#define LG_CLOCK_MIN_DELTA 100UL
#define LG_CLOCK_MAX_DELTA ULONG_MAX

/*G:031
* The second method of communicating with the Host is to via "struct
* lguest_data". Once the Guest's initialization hypercall tells the Host where
* this is, the Guest and Host both publish information in it.
:*/
struct lguest_data {
/*
* 512 == enabled (same as eflags in normal hardware). The Guest
* changes interrupts so often that a hypercall is too slow.
*/
unsigned int irq_enabled;
/* Fine-grained interrupt disabling by the Guest */
DECLARE_BITMAP(blocked_interrupts, LGUEST_IRQS);

/*
* The Host writes the virtual address of the last page fault here,
* which saves the Guest a hypercall. CR2 is the native register where
* this address would normally be found.
*/
unsigned long cr2;

/* Wallclock time set by the Host. */
struct timespec time;

/*
* Interrupt pending set by the Host. The Guest should do a hypercall
* if it re-enables interrupts and sees this set (to X86_EFLAGS_IF).
*/
int irq_pending;

/*
* Async hypercall ring. Instead of directly making hypercalls, we can
* place them in here for processing the next time the Host wants.
* This batching can be quite efficient.
*/

/* 0xFF == done (set by Host), 0 == pending (set by Guest). */
u8 hcall_status[LHCALL_RING_SIZE];
/* The actual registers for the hypercalls. */
struct hcall_args hcalls[LHCALL_RING_SIZE];

/* Fields initialized by the Host at boot: */
/* Memory not to try to access */
unsigned long reserve_mem;
/* KHz for the TSC clock. */
u32 tsc_khz;

/* Fields initialized by the Guest at boot: */
/* Instruction range to suppress interrupts even if enabled */
unsigned long noirq_start, noirq_end;
/* Address above which page tables are all identical. */
unsigned long kernel_address;
/* The vector to try to use for system calls (0x40 or 0x80). */
unsigned int syscall_vec;
};
extern struct lguest_data lguest_data;
#endif /* __ASSEMBLY__ */
#endif /* _LINUX_LGUEST_H */