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