1/*
2 * Things the lguest guest needs to know.  Note: like all lguest interfaces,
3 * this is subject to wild and random change between versions.
4 */
5#ifndef _LINUX_LGUEST_H
6#define _LINUX_LGUEST_H
7
8#ifndef __ASSEMBLY__
9#include <linux/time.h>
10#include <asm/irq.h>
11#include <asm/lguest_hcall.h>
12
13#define LG_CLOCK_MIN_DELTA	100UL
14#define LG_CLOCK_MAX_DELTA	ULONG_MAX
15
16/*G:031
17 * The second method of communicating with the Host is to via "struct
18 * lguest_data".  Once the Guest's initialization hypercall tells the Host where
19 * this is, the Guest and Host both publish information in it.
20:*/
21struct lguest_data {
22	/*
23	 * 512 == enabled (same as eflags in normal hardware).  The Guest
24	 * changes interrupts so often that a hypercall is too slow.
25	 */
26	unsigned int irq_enabled;
27	/* Fine-grained interrupt disabling by the Guest */
28	DECLARE_BITMAP(blocked_interrupts, LGUEST_IRQS);
29
30	/*
31	 * The Host writes the virtual address of the last page fault here,
32	 * which saves the Guest a hypercall.  CR2 is the native register where
33	 * this address would normally be found.
34	 */
35	unsigned long cr2;
36
37	/* Wallclock time set by the Host. */
38	struct timespec time;
39
40	/*
41	 * Interrupt pending set by the Host.  The Guest should do a hypercall
42	 * if it re-enables interrupts and sees this set (to X86_EFLAGS_IF).
43	 */
44	int irq_pending;
45
46	/*
47	 * Async hypercall ring.  Instead of directly making hypercalls, we can
48	 * place them in here for processing the next time the Host wants.
49	 * This batching can be quite efficient.
50	 */
51
52	/* 0xFF == done (set by Host), 0 == pending (set by Guest). */
53	u8 hcall_status[LHCALL_RING_SIZE];
54	/* The actual registers for the hypercalls. */
55	struct hcall_args hcalls[LHCALL_RING_SIZE];
56
57/* Fields initialized by the Host at boot: */
58	/* Memory not to try to access */
59	unsigned long reserve_mem;
60	/* KHz for the TSC clock. */
61	u32 tsc_khz;
62
63/* Fields initialized by the Guest at boot: */
64	/* Instruction to suppress interrupts even if enabled */
65	unsigned long noirq_iret;
66	/* Address above which page tables are all identical. */
67	unsigned long kernel_address;
68	/* The vector to try to use for system calls (0x40 or 0x80). */
69	unsigned int syscall_vec;
70};
71extern struct lguest_data lguest_data;
72#endif /* __ASSEMBLY__ */
73#endif	/* _LINUX_LGUEST_H */
74