[PATCH v4 09/11] s390x/pci: use I/O Address Translation assist when interpreting

[Matthew Rosato]

Allow the underlying kvm host to handle the Refresh PCI Translation
instruction intercepts.

Signed-off-by: Matthew Rosato <mjrosato@linux.ibm.com>
---
 hw/s390x/s390-pci-bus.c          |  6 ++---
 hw/s390x/s390-pci-inst.c         | 42 +++++++++++++++++++++++++++++---
 hw/s390x/s390-pci-kvm.c          | 21 ++++++++++++++++
 include/hw/s390x/s390-pci-inst.h |  2 +-
 include/hw/s390x/s390-pci-kvm.h  | 10 ++++++++
 5 files changed, 74 insertions(+), 7 deletions(-)

diff --git a/hw/s390x/s390-pci-bus.c b/hw/s390x/s390-pci-bus.c
index 513a276711..32894fbe9c 100644
--- a/hw/s390x/s390-pci-bus.c
+++ b/hw/s390x/s390-pci-bus.c
@@ -197,7 +197,7 @@ void s390_pci_sclp_deconfigure(SCCB *sccb)
             pci_dereg_irqs(pbdev);
         }
         if (pbdev->iommu->enabled) {
-            pci_dereg_ioat(pbdev->iommu);
+            pci_dereg_ioat(pbdev);
         }
         pbdev->state = ZPCI_FS_STANDBY;
         rc = SCLP_RC_NORMAL_COMPLETION;
@@ -1265,7 +1265,7 @@ static void s390_pcihost_reset(DeviceState *dev)
                 pci_dereg_irqs(pbdev);
             }
             if (pbdev->iommu->enabled) {
-                pci_dereg_ioat(pbdev->iommu);
+                pci_dereg_ioat(pbdev);
             }
             pbdev->state = ZPCI_FS_STANDBY;
             s390_pci_perform_unplug(pbdev);
@@ -1406,7 +1406,7 @@ static void s390_pci_device_reset(DeviceState *dev)
         pci_dereg_irqs(pbdev);
     }
     if (pbdev->iommu->enabled) {
-        pci_dereg_ioat(pbdev->iommu);
+        pci_dereg_ioat(pbdev);
     }
 
     fmb_timer_free(pbdev);
diff --git a/hw/s390x/s390-pci-inst.c b/hw/s390x/s390-pci-inst.c
index f7b01e2059..86bb04e859 100644
--- a/hw/s390x/s390-pci-inst.c
+++ b/hw/s390x/s390-pci-inst.c
@@ -969,6 +969,19 @@ int pci_dereg_irqs(S390PCIBusDevice *pbdev)
     return 0;
 }
 
+static int reg_ioat_interp(S390PCIBusDevice *pbdev, uint64_t iota)
+{
+    int rc;
+
+    rc = s390_pci_kvm_ioat_enable(pbdev, iota);
+    if (rc) {
+        return rc;
+    }
+
+    pbdev->iommu->enabled = true;
+    return 0;
+}
+
 static int reg_ioat(CPUS390XState *env, S390PCIBusDevice *pbdev, ZpciFib fib,
                     uintptr_t ra)
 {
@@ -986,6 +999,16 @@ static int reg_ioat(CPUS390XState *env, S390PCIBusDevice 
*pbdev, ZpciFib fib,
         return -EINVAL;
     }
 
+    /* If this is an interpreted device, we must use the IOAT assist */
+    if (pbdev->interp) {
+        if (reg_ioat_interp(pbdev, g_iota)) {
+            error_report("failure starting ioat assist");
+            s390_program_interrupt(env, PGM_OPERAND, ra);
+            return -EINVAL;
+        }
+        return 0;
+    }
+
     /* currently we only support designation type 1 with translation */
     if (!(dt == ZPCI_IOTA_RTTO && t)) {
         error_report("unsupported ioat dt %d t %d", dt, t);
@@ -1002,8 +1025,21 @@ static int reg_ioat(CPUS390XState *env, S390PCIBusDevice 
*pbdev, ZpciFib fib,
     return 0;
 }
 
-void pci_dereg_ioat(S390PCIIOMMU *iommu)
+static void dereg_ioat_interp(S390PCIBusDevice *pbdev)
+{
+    s390_pci_kvm_ioat_disable(pbdev);
+    pbdev->iommu->enabled = false;
+}
+
+void pci_dereg_ioat(S390PCIBusDevice *pbdev)
 {
+    S390PCIIOMMU *iommu = pbdev->iommu;
+
+    if (pbdev->interp) {
+        dereg_ioat_interp(pbdev);
+        return;
+    }
+
     s390_pci_iommu_disable(iommu);
     iommu->pba = 0;
     iommu->pal = 0;
@@ -1228,7 +1264,7 @@ int mpcifc_service_call(S390CPU *cpu, uint8_t r1, 
uint64_t fiba, uint8_t ar,
             cc = ZPCI_PCI_LS_ERR;
             s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
         } else {
-            pci_dereg_ioat(pbdev->iommu);
+            pci_dereg_ioat(pbdev);
         }
         break;
     case ZPCI_MOD_FC_REREG_IOAT:
@@ -1239,7 +1275,7 @@ int mpcifc_service_call(S390CPU *cpu, uint8_t r1, 
uint64_t fiba, uint8_t ar,
             cc = ZPCI_PCI_LS_ERR;
             s390_set_status_code(env, r1, ZPCI_MOD_ST_SEQUENCE);
         } else {
-            pci_dereg_ioat(pbdev->iommu);
+            pci_dereg_ioat(pbdev);
             if (reg_ioat(env, pbdev, fib, ra)) {
                 cc = ZPCI_PCI_LS_ERR;
                 s390_set_status_code(env, r1, ZPCI_MOD_ST_INSUF_RES);
diff --git a/hw/s390x/s390-pci-kvm.c b/hw/s390x/s390-pci-kvm.c
index ebb862abd0..2332efd676 100644
--- a/hw/s390x/s390-pci-kvm.c
+++ b/hw/s390x/s390-pci-kvm.c
@@ -137,3 +137,24 @@ int s390_pci_kvm_aif_disable(S390PCIBusDevice *pbdev)
 
     return kvm_vm_ioctl(kvm_state, KVM_S390_ZPCI_OP, &args);
 }
+
+int s390_pci_kvm_ioat_enable(S390PCIBusDevice *pbdev, uint64_t iota)
+{
+    struct kvm_s390_zpci_op args = {
+        .fh = pbdev->fh,
+        .op = KVM_S390_ZPCIOP_REG_IOAT,
+        .u.reg_ioat.iota = iota
+    };
+
+    return kvm_vm_ioctl(kvm_state, KVM_S390_ZPCI_OP, &args);
+}
+
+int s390_pci_kvm_ioat_disable(S390PCIBusDevice *pbdev)
+{
+    struct kvm_s390_zpci_op args = {
+        .fh = pbdev->fh,
+        .op = KVM_S390_ZPCIOP_DEREG_IOAT
+    };
+
+    return kvm_vm_ioctl(kvm_state, KVM_S390_ZPCI_OP, &args);
+}
diff --git a/include/hw/s390x/s390-pci-inst.h b/include/hw/s390x/s390-pci-inst.h
index a55c448aad..13566fb7b4 100644
--- a/include/hw/s390x/s390-pci-inst.h
+++ b/include/hw/s390x/s390-pci-inst.h
@@ -99,7 +99,7 @@ typedef struct ZpciFib {
 } QEMU_PACKED ZpciFib;
 
 int pci_dereg_irqs(S390PCIBusDevice *pbdev);
-void pci_dereg_ioat(S390PCIIOMMU *iommu);
+void pci_dereg_ioat(S390PCIBusDevice *pbdev);
 int clp_service_call(S390CPU *cpu, uint8_t r2, uintptr_t ra);
 int pcilg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra);
 int pcistg_service_call(S390CPU *cpu, uint8_t r1, uint8_t r2, uintptr_t ra);
diff --git a/include/hw/s390x/s390-pci-kvm.h b/include/hw/s390x/s390-pci-kvm.h
index 09004d3f6c..e52e92d0f0 100644
--- a/include/hw/s390x/s390-pci-kvm.h
+++ b/include/hw/s390x/s390-pci-kvm.h
@@ -23,6 +23,8 @@ int s390_pci_kvm_interp_enable(S390PCIBusDevice *pbdev);
 int s390_pci_kvm_interp_disable(S390PCIBusDevice *pbdev);
 int s390_pci_kvm_aif_enable(S390PCIBusDevice *pbdev, ZpciFib *fib, bool 
assist);
 int s390_pci_kvm_aif_disable(S390PCIBusDevice *pbdev);
+int s390_pci_kvm_ioat_enable(S390PCIBusDevice *pbdev, uint64_t iota);
+int s390_pci_kvm_ioat_disable(S390PCIBusDevice *pbdev);
 #else
 static inline bool s390_pci_kvm_zpciop_allowed(void)
 {
@@ -53,6 +55,14 @@ static inline int s390_pci_kvm_aif_disable(S390PCIBusDevice 
*pbdev)
 {
     return -EINVAL;
 }
+int s390_pci_kvm_ioat_enable(S390PCIBusDevice *pbdev, uint64_t iota)
+{
+    return -EINVAL;
+}
+int s390_pci_kvm_ioat_disable(S390PCIBusDevice *pbdev)
+{
+    return -EINVAL;
+}
 #endif
 
 #endif
-- 
2.27.0