Add wrappers to do hypercalls using VMCALL/VMMCALL and Xen's register ABI
(as opposed to full Xen-style hypercalls through a hypervisor provided
page). Using the common helpers dedups a pile of code, and uses the
native hypercall instruction when running on AMD.
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
.../selftests/kvm/include/x86_64/processor.h | 2 +
.../selftests/kvm/lib/x86_64/processor.c | 10 +++
.../selftests/kvm/x86_64/xen_shinfo_test.c | 63 +++----------------
3 files changed, 21 insertions(+), 54 deletions(-)
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 53ffa43c90db..90387ddcb2a9 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -1063,6 +1063,8 @@ uint64_t *vm_get_page_table_entry(struct kvm_vm *vm, uint64_t vaddr);
uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
uint64_t a3);
+uint64_t __xen_hypercall(uint64_t nr, uint64_t a0, void *a1);
+void xen_hypercall(uint64_t nr, uint64_t a0, void *a1);
void __vm_xsave_require_permission(int bit, const char *name);
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index ff901cb47ffc..c39a4353ba19 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -1161,6 +1161,16 @@ uint64_t kvm_hypercall(uint64_t nr, uint64_t a0, uint64_t a1, uint64_t a2,
return X86_HYPERCALL("a"(nr), "b"(a0), "c"(a1), "d"(a2), "S"(a3));
}
+uint64_t __xen_hypercall(uint64_t nr, uint64_t a0, void *a1)
+{
+ return X86_HYPERCALL("a"(nr), "D"(a0), "S"(a1));
+}
+
+void xen_hypercall(uint64_t nr, uint64_t a0, void *a1)
+{
+ GUEST_ASSERT(!__xen_hypercall(nr, a0, a1));
+}
+
const struct kvm_cpuid2 *kvm_get_supported_hv_cpuid(void)
{
static struct kvm_cpuid2 *cpuid;
diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
index 6a838df69174..1380947af1fe 100644
--- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
@@ -228,15 +228,8 @@ static void guest_code(void)
/* Our turn. Deliver event channel (to ourselves) with
* EVTCHNOP_send hypercall. */
- unsigned long rax;
struct evtchn_send s = { .port = 127 };
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_event_channel_op),
- "D" (EVTCHNOP_send),
- "S" (&s));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_event_channel_op, EVTCHNOP_send, &s);
guest_wait_for_irq();
@@ -245,24 +238,15 @@ static void guest_code(void)
/* Deliver "outbound" event channel to an eventfd which
* happens to be one of our own irqfds. */
s.port = 197;
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_event_channel_op),
- "D" (EVTCHNOP_send),
- "S" (&s));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_event_channel_op, EVTCHNOP_send, &s);
guest_wait_for_irq();
GUEST_SYNC(13);
/* Set a timer 100ms in the future. */
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_set_timer_op),
- "D" (rs->state_entry_time + 100000000));
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_set_timer_op,
+ rs->state_entry_time + 100000000, NULL);
GUEST_SYNC(14);
@@ -284,37 +268,19 @@ static void guest_code(void)
.timeout = 0,
};
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_sched_op),
- "D" (SCHEDOP_poll),
- "S" (&p));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_sched_op, SCHEDOP_poll, &p);
GUEST_SYNC(17);
/* Poll for an unset port and wait for the timeout. */
p.timeout = 100000000;
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_sched_op),
- "D" (SCHEDOP_poll),
- "S" (&p));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_sched_op, SCHEDOP_poll, &p);
GUEST_SYNC(18);
/* A timer will wake the masked port we're waiting on, while we poll */
p.timeout = 0;
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_sched_op),
- "D" (SCHEDOP_poll),
- "S" (&p));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_sched_op, SCHEDOP_poll, &p);
GUEST_SYNC(19);
@@ -322,13 +288,7 @@ static void guest_code(void)
* actual interrupt, while we're polling on a different port. */
ports[0]++;
p.timeout = 0;
- __asm__ __volatile__ ("vmcall" :
- "=a" (rax) :
- "a" (__HYPERVISOR_sched_op),
- "D" (SCHEDOP_poll),
- "S" (&p));
-
- GUEST_ASSERT(rax == 0);
+ xen_hypercall(__HYPERVISOR_sched_op, SCHEDOP_poll, &p);
guest_wait_for_irq();
@@ -363,12 +323,7 @@ static void guest_code(void)
* timer IRQ is dropped due to an invalid event channel.
*/
for (i = 0; i < 100 && !guest_saw_irq; i++)
- asm volatile("vmcall"
- : "=a" (rax)
- : "a" (__HYPERVISOR_sched_op),
- "D" (SCHEDOP_poll),
- "S" (&p)
- : "memory");
+ __xen_hypercall(__HYPERVISOR_sched_op, SCHEDOP_poll, &p);
/*
* Re-send the timer IRQ if it was (likely) dropped due to the timer
--
2.39.1.519.gcb327c4b5f-goog
