On 12/10/21 8:27 AM, Christian Borntraeger wrote:
Am 07.12.21 um 21:57 schrieb Matthew Rosato:
The guest must have access to certain facilities in order to allow
interpretive execution of zPCI instructions and adapter event
notifications. However, there are some cases where a guest might
disable interpretation -- provide a mechanism via which we can defer
enabling the associated zPCI interpretation facilities until the guest
indicates it wishes to use them.
Signed-off-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
---
arch/s390/include/asm/kvm_host.h | 4 +++
arch/s390/kvm/kvm-s390.c | 43 ++++++++++++++++++++++++++++++++
arch/s390/kvm/kvm-s390.h | 10 ++++++++
3 files changed, 57 insertions(+)
diff --git a/arch/s390/include/asm/kvm_host.h
b/arch/s390/include/asm/kvm_host.h
index 3f147b8d050b..38982c1de413 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -252,7 +252,10 @@ struct kvm_s390_sie_block {
#define ECB2_IEP 0x20
#define ECB2_PFMFI 0x08
#define ECB2_ESCA 0x04
+#define ECB2_ZPCI_LSI 0x02
__u8 ecb2; /* 0x0062 */
+#define ECB3_AISI 0x20
+#define ECB3_AISII 0x10
#define ECB3_DEA 0x08
#define ECB3_AES 0x04
#define ECB3_RI 0x01
@@ -938,6 +941,7 @@ struct kvm_arch{
int use_cmma;
int use_pfmfi;
int use_skf;
+ int use_zpci_interp;
int user_cpu_state_ctrl;
int user_sigp;
int user_stsi;
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index a680f2a02b67..361d742cdf0d 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -1023,6 +1023,47 @@ static int kvm_s390_vm_set_crypto(struct kvm
*kvm, struct kvm_device_attr *attr)
return 0;
}
+static void kvm_s390_vcpu_pci_setup(struct kvm_vcpu *vcpu)
+{
+ /*
+ * If the facilities aren't available for PCI interpretation and
+ * interrupt forwarding, we shouldn't be here.
+ */
This reads like we want a WARN_ON or BUG_ON, but as we call this
uncoditionally this is
actually a valid check. So instead of "shouldn't be here" say something
like "bail out
if interpretion is not active". ?
Right, this comment block is plain wrong. We expect to get here under
multiple circumstances and its OK for this bit to be off:
- initial vcpu setup (use_zpci_interp is off)
- Right after we set use_zpci_interp=1 (turn on ECB for all vcpu)
- hotplug vcpu setup (use_zpci_interp might be on or off)
Will re-word.
+ if (!vcpu->kvm->arch.use_zpci_interp)
+ return;
+
+ vcpu->arch.sie_block->ecb2 |= ECB2_ZPCI_LSI;
+ vcpu->arch.sie_block->ecb3 |= ECB3_AISII + ECB3_AISI;
+}
+
+void kvm_s390_vcpu_pci_enable_interp(struct kvm *kvm)
+{
+ struct kvm_vcpu *vcpu;
+ int i;
+
+ /*
+ * If host facilities are available, turn on interpretation for the
+ * life of this guest
+ */
+ if (!test_facility(69) || !test_facility(70) ||
!test_facility(71) ||
+ !test_facility(72))
+ return;
Wouldnt that also enable interpretion for VSIE? I guess we should check
for the
sclp facilities from patches 1,2,3, and 4 instead.
Good point -- will change.
