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