[PATCH v1 3/4] s390/kvm: add kvm_s390_vsie_mvpg_check needed for VSIE MVPG
From: Claudio Imbrenda
Date: Fri Dec 18 2020 - 09:19:06 EST
Add kvm_s390_vsie_mvpg_check to perform the necessary checks in case an
MVPG instruction intercepts in a VSIE guest.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx>
---
arch/s390/kvm/gaccess.c | 55 +++++++++++++++++++++++++++++++++++++++++
arch/s390/kvm/gaccess.h | 3 +++
2 files changed, 58 insertions(+)
diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c
index 8e256a233583..90e9baff6eac 100644
--- a/arch/s390/kvm/gaccess.c
+++ b/arch/s390/kvm/gaccess.c
@@ -1228,3 +1228,58 @@ int kvm_s390_shadow_fault(struct kvm_vcpu *vcpu, struct gmap *sg,
mmap_read_unlock(sg->mm);
return rc;
}
+
+static int kvm_s390_mvpg_check_one(struct kvm_vcpu *vcpu, unsigned long *addr,
+ const int edat, const union asce asce,
+ const enum gacc_mode mode, unsigned long *pteptr)
+{
+ enum prot_type prot;
+ int rc;
+
+ rc = guest_translate(vcpu, *addr, addr, asce, mode, &prot, pteptr);
+ if (rc <= 0)
+ return rc;
+
+ switch (rc) {
+ case PGM_REGION_FIRST_TRANS:
+ case PGM_REGION_SECOND_TRANS:
+ case PGM_REGION_THIRD_TRANS:
+ case PGM_SEGMENT_TRANSLATION:
+ if (!edat)
+ return trans_exc(vcpu, rc, *addr, 0, mode, prot);
+ *pteptr |= 4;
+ fallthrough;
+ case PGM_PAGE_TRANSLATION:
+ return -ENOENT;
+ default:
+ return rc;
+ }
+}
+
+int kvm_s390_vsie_mvpg_check(struct kvm_vcpu *vcpu, unsigned long r1,
+ unsigned long r2, void *gpei)
+{
+ unsigned long pei[2] = {0};
+ union ctlreg0 cr0;
+ union asce cr1;
+ int edat, rc1, rc2;
+
+ cr0.val = vcpu->arch.sie_block->gcr[0];
+ cr1.val = vcpu->arch.sie_block->gcr[1];
+ edat = cr0.edat && test_kvm_facility(vcpu->kvm, 8);
+
+ rc1 = kvm_s390_mvpg_check_one(vcpu, &r1, edat, cr1, GACC_FETCH, pei);
+ rc2 = kvm_s390_mvpg_check_one(vcpu, &r2, edat, cr1, GACC_STORE, pei + 1);
+
+ if (rc1 == -ENOENT || rc2 == -ENOENT) {
+ memcpy(gpei, pei, sizeof(pei));
+ return -ENOENT;
+ }
+
+ if (rc2 < 0)
+ return rc2;
+ if (rc1 < 0)
+ return rc1;
+
+ return 0;
+}
diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h
index f4c51756c462..2c53cee3b29f 100644
--- a/arch/s390/kvm/gaccess.h
+++ b/arch/s390/kvm/gaccess.h
@@ -166,6 +166,9 @@ int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar,
int access_guest(struct kvm_vcpu *vcpu, unsigned long ga, u8 ar, void *data,
unsigned long len, enum gacc_mode mode);
+int kvm_s390_vsie_mvpg_check(struct kvm_vcpu *vcpu, unsigned long r1,
+ unsigned long r2, void *gpei);
+
int access_guest_real(struct kvm_vcpu *vcpu, unsigned long gra,
void *data, unsigned long len, enum gacc_mode mode);
--
2.26.2