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