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-rw-r--r--arch/x86/include/asm/lguest_hcall.h18
1 files changed, 9 insertions, 9 deletions
diff --git a/arch/x86/include/asm/lguest_hcall.h b/arch/x86/include/asm/lguest_hcall.h
index d31c4a684078..ba0eed8aa1a6 100644
--- a/arch/x86/include/asm/lguest_hcall.h
+++ b/arch/x86/include/asm/lguest_hcall.h
@@ -30,27 +30,27 @@
30#include <asm/hw_irq.h> 30#include <asm/hw_irq.h>
31#include <asm/kvm_para.h> 31#include <asm/kvm_para.h>
32 32
33/*G:031 But first, how does our Guest contact the Host to ask for privileged 33/*G:030
34 * 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 * operations? There are two ways: the direct way is to make a "hypercall",
35 * to make requests of the Host Itself. 36 * to make requests of the Host Itself.
36 * 37 *
37 * We use the KVM hypercall mechanism. Seventeen hypercalls are 38 * We use the KVM hypercall mechanism, though completely different hypercall
38 * available: the hypercall number is put in the %eax register, and the 39 * numbers. Seventeen hypercalls are available: the hypercall number is put in
39 * arguments (when required) are placed in %ebx, %ecx, %edx and %esi. 40 * the %eax register, and the arguments (when required) are placed in %ebx,
40 * If a return value makes sense, it's returned in %eax. 41 * %ecx, %edx and %esi. If a return value makes sense, it's returned in %eax.
41 * 42 *
42 * Grossly invalid calls result in Sudden Death at the hands of the vengeful 43 * 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 * Host, rather than returning failure. This reflects Winston Churchill's
44 * definition of a gentleman: "someone who is only rude intentionally". */ 45 * definition of a gentleman: "someone who is only rude intentionally".
45/*:*/ 46:*/
46 47
47/* Can't use our min() macro here: needs to be a constant */ 48/* Can't use our min() macro here: needs to be a constant */
48#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32) 49#define LGUEST_IRQS (NR_IRQS < 32 ? NR_IRQS: 32)
49 50
50#define LHCALL_RING_SIZE 64 51#define LHCALL_RING_SIZE 64
51struct hcall_args { 52struct hcall_args {
52 /* These map directly onto eax, ebx, ecx, edx and esi 53 /* These map directly onto eax/ebx/ecx/edx/esi in struct lguest_regs */
53 * in struct lguest_regs */
54 unsigned long arg0, arg1, arg2, arg3, arg4; 54 unsigned long arg0, arg1, arg2, arg3, arg4;
55}; 55};
56 56