1/* Architecture specific portion of the lguest hypercalls */
 2#ifndef _ASM_X86_LGUEST_HCALL_H
 3#define _ASM_X86_LGUEST_HCALL_H
 4
 5#define LHCALL_FLUSH_ASYNC	0
 6#define LHCALL_LGUEST_INIT	1
 7#define LHCALL_SHUTDOWN		2
 8#define LHCALL_NEW_PGTABLE	4
 9#define LHCALL_FLUSH_TLB	5
10#define LHCALL_LOAD_IDT_ENTRY	6
11#define LHCALL_SET_STACK	7
12#define LHCALL_TS		8
13#define LHCALL_SET_CLOCKEVENT	9
14#define LHCALL_HALT		10
15#define LHCALL_SET_PMD		13
16#define LHCALL_SET_PTE		14
17#define LHCALL_SET_PGD		15
18#define LHCALL_LOAD_TLS		16
19#define LHCALL_LOAD_GDT_ENTRY	18
20#define LHCALL_SEND_INTERRUPTS	19
21
22#define LGUEST_TRAP_ENTRY 0x1F
23
24/* Argument number 3 to LHCALL_LGUEST_SHUTDOWN */
25#define LGUEST_SHUTDOWN_POWEROFF	1
26#define LGUEST_SHUTDOWN_RESTART		2
27
28#ifndef __ASSEMBLY__
29#include <asm/hw_irq.h>
30
31/*G:030
32 * But first, how does our Guest contact the Host to ask for privileged
33 * operations?  There are two ways: the direct way is to make a "hypercall",
34 * to make requests of the Host Itself.
35 *
36 * Our hypercall mechanism uses the highest unused trap code (traps 32 and
37 * above are used by real hardware interrupts).  Seventeen hypercalls are
38 * available: the hypercall number is put in the %eax register, and the
39 * arguments (when required) are placed in %ebx, %ecx, %edx and %esi.
40 * If a return value makes sense, it's returned in %eax.
41 *
42 * Grossly invalid calls result in Sudden Death at the hands of the vengeful
43 * Host, rather than returning failure.  This reflects Winston Churchill's
44 * definition of a gentleman: "someone who is only rude intentionally".
45 */
46static inline unsigned long
47hcall(unsigned long call,
48      unsigned long arg1, unsigned long arg2, unsigned long arg3,
49      unsigned long arg4)
50{
51	/* "int" is the Intel instruction to trigger a trap. */
52	asm volatile("int $" __stringify(LGUEST_TRAP_ENTRY)
53		     /* The call in %eax (aka "a") might be overwritten */
54		     : "=a"(call)
55		       /* The arguments are in %eax, %ebx, %ecx, %edx & %esi */
56		     : "a"(call), "b"(arg1), "c"(arg2), "d"(arg3), "S"(arg4)
57		       /* "memory" means this might write somewhere in memory.
58			* This isn't true for all calls, but it's safe to tell
59			* gcc that it might happen so it doesn't get clever. */
60		     : "memory");
61	return call;
62}
63/*:*/
64
65/* Can't use our min() macro here: needs to be a constant */
66#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)
67
68#define LHCALL_RING_SIZE 64
69struct hcall_args {
70	/* These map directly onto eax/ebx/ecx/edx/esi in struct lguest_regs */
71	unsigned long arg0, arg1, arg2, arg3, arg4;
72};
73
74#endif /* !__ASSEMBLY__ */
75#endif /* _ASM_X86_LGUEST_HCALL_H */