[PATCH v4 17/36] KVM: s390: protvirt: Add new gprs location handling

Christian Borntraeger
2020-02-24T11:46:16Z

From: Janosch Frank <frankja@linux.ibm.com>

Guest registers for protected guests are stored at offset 0x380. We
will copy those to the usual places. Long term we could refactor this
or use register access functions.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
[borntraeger@de.ibm.com: patch merging, splitting, fixing]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
arch/s390/include/asm/kvm_host.h | 4 +++-
arch/s390/kvm/kvm-s390.c | 11 +++++++++++
2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index ba3364b37159..4fcbb055a565 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -343,7 +343,9 @@ struct kvm_s390_itdb {
struct sie_page {
struct kvm_s390_sie_block sie_block;
struct mcck_volatile_info mcck_info; /* 0x0200 */
- __u8 reserved218[1000]; /* 0x0218 */
+ __u8 reserved218[360]; /* 0x0218 */
+ __u64 pv_grregs[16]; /* 0x0380 */
+ __u8 reserved400[512]; /* 0x0400 */
struct kvm_s390_itdb itdb; /* 0x0600 */
__u8 reserved700[2304]; /* 0x0700 */
};
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 85db915244fe..93bf8f103f05 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4056,6 +4056,7 @@ static int vcpu_post_run(struct kvm_vcpu *vcpu, int exit_reason)
static int __vcpu_run(struct kvm_vcpu *vcpu)
{
int rc, exit_reason;
+ struct sie_page *sie_page = (struct sie_page *)vcpu->arch.sie_block;

/*
* We try to hold kvm->srcu during most of vcpu_run (except when run-
@@ -4077,8 +4078,18 @@ static int __vcpu_run(struct kvm_vcpu *vcpu)
guest_enter_irqoff();
__disable_cpu_timer_accounting(vcpu);
local_irq_enable();
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ memcpy(sie_page->pv_grregs,
+ vcpu->run->s.regs.gprs,
+ sizeof(sie_page->pv_grregs));
+ }
exit_reason = sie64a(vcpu->arch.sie_block,
vcpu->run->s.regs.gprs);
+ if (kvm_s390_pv_cpu_is_protected(vcpu)) {
+ memcpy(vcpu->run->s.regs.gprs,
+ sie_page->pv_grregs,
+ sizeof(sie_page->pv_grregs));
+ }
local_irq_disable();
__enable_cpu_timer_accounting(vcpu);
guest_exit_irqoff();
--
2.25.0