KVM: s390: vsie: support vectory facility (SIMD)

As soon as guest 2 is allowed to use the vector facility (indicated via
STFLE), it can also enable it for guest 3. We have to take care of the
sattellite block that might be used when not relying on lazy vector
copying (not the case for KVM).

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
index 4e2c71cced48..6d9f4058ce15 100644
--- a/arch/s390/kvm/vsie.c
+++ b/arch/s390/kvm/vsie.c
@@ -307,6 +307,11 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 			prefix_unmapped(vsie_page);
 		scb_s->ecb |= scb_o->ecb & 0x10U;
 	}
+	/* SIMD */
+	if (test_kvm_facility(vcpu->kvm, 129)) {
+		scb_s->eca |= scb_o->eca & 0x00020000U;
+		scb_s->ecd |= scb_o->ecd & 0x20000000U;
+	}
 
 	prepare_ibc(vcpu, vsie_page);
 	rc = shadow_crycb(vcpu, vsie_page);
@@ -452,6 +457,13 @@ static void unpin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 		unpin_guest_page(vcpu->kvm, gpa, hpa);
 		scb_s->itdba = 0;
 	}
+
+	hpa = scb_s->gvrd;
+	if (hpa) {
+		gpa = scb_o->gvrd & ~0x1ffUL;
+		unpin_guest_page(vcpu->kvm, gpa, hpa);
+		scb_s->gvrd = 0;
+	}
 }
 
 /*
@@ -510,6 +522,25 @@ static int pin_blocks(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
 			goto unpin;
 		scb_s->itdba = hpa;
 	}
+
+	gpa = scb_o->gvrd & ~0x1ffUL;
+	if (gpa && (scb_s->eca & 0x00020000U) &&
+	    !(scb_s->ecd & 0x20000000U)) {
+		if (!(gpa & ~0x1fffUL)) {
+			rc = set_validity_icpt(scb_s, 0x1310U);
+			goto unpin;
+		}
+		/*
+		 * 512 bytes vector registers cannot cross page boundaries
+		 * if this block gets bigger, we have to shadow it.
+		 */
+		rc = pin_guest_page(vcpu->kvm, gpa, &hpa);
+		if (rc == -EINVAL)
+			rc = set_validity_icpt(scb_s, 0x1310U);
+		if (rc)
+			goto unpin;
+		scb_s->gvrd = hpa;
+	}
 	return 0;
 unpin:
 	unpin_blocks(vcpu, vsie_page);