[Qemu-devel] [PATCH 6/7] s390x/kvm: Reworked/fixed handling of cc3 in kvm_handle_css_inst()

[Christian Borntraeger <borntraeger@de.ibm.com>]

From: Thomas Huth <thuth@linux.vnet.ibm.com>

Consolidated the setting of the condition code in kvm_handle_css_inst().
For the (unhandled) instructions EQBS and SQBS, we have to return
an operation exception instead of cc3. Also removed the is_ioinst()
function to avoid decoding the opcode twice.

Signed-off-by: Thomas Huth <thuth@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 target-s390x/kvm.c | 59 ++++++++++--------------------------------------------
 1 file changed, 11 insertions(+), 48 deletions(-)

diff --git a/target-s390x/kvm.c b/target-s390x/kvm.c
index 60e94f8..1b123cf 100644
--- a/target-s390x/kvm.c
+++ b/target-s390x/kvm.c
@@ -532,50 +532,19 @@ static int kvm_handle_css_inst(S390CPU *cpu, struct kvm_run *run,
         no_cc = 1;
         r = ioinst_handle_sal(env, env->regs[1]);
         break;
-    default:
-        r = -1;
+    case PRIV_SIGA:
+        /* Not provided, set CC = 3 for subchannel not operational */
+        r = 3;
         break;
+    default:
+        return -1;
     }
 
-    if (r >= 0) {
-        if (!no_cc) {
-            setcc(cpu, r);
-        }
-        r = 0;
-    } else if (r < -1) {
-        r = 0;
-    }
-    return r;
-}
-
-static int is_ioinst(uint8_t ipa0, uint8_t ipa1, uint8_t ipb)
-{
-    int ret = 0;
-    uint16_t ipa = (ipa0 << 8) | ipa1;
-
-    switch (ipa) {
-    case IPA0_B2 | PRIV_CSCH:
-    case IPA0_B2 | PRIV_HSCH:
-    case IPA0_B2 | PRIV_MSCH:
-    case IPA0_B2 | PRIV_SSCH:
-    case IPA0_B2 | PRIV_STSCH:
-    case IPA0_B2 | PRIV_TPI:
-    case IPA0_B2 | PRIV_SAL:
-    case IPA0_B2 | PRIV_RSCH:
-    case IPA0_B2 | PRIV_STCRW:
-    case IPA0_B2 | PRIV_STCPS:
-    case IPA0_B2 | PRIV_RCHP:
-    case IPA0_B2 | PRIV_SCHM:
-    case IPA0_B2 | PRIV_CHSC:
-    case IPA0_B2 | PRIV_SIGA:
-    case IPA0_B2 | PRIV_XSCH:
-    case IPA0_B9 | PRIV_EQBS:
-    case IPA0_EB | PRIV_SQBS:
-        ret = 1;
-        break;
+    if (r >= 0 && !no_cc) {
+        setcc(cpu, r);
     }
 
-    return ret;
+    return 0;
 }
 
 static int handle_priv(S390CPU *cpu, struct kvm_run *run,
@@ -591,15 +560,9 @@ static int handle_priv(S390CPU *cpu, struct kvm_run *run,
             r = kvm_sclp_service_call(cpu, run, ipbh0);
             break;
         default:
-            if (is_ioinst(ipa0, ipa1, ipb)) {
-                r = kvm_handle_css_inst(cpu, run, ipa0, ipa1, ipb);
-                if (r == -1) {
-                    setcc(cpu, 3);
-                    r = 0;
-                }
-            } else {
-                dprintf("KVM: unknown PRIV: 0x%x\n", ipa1);
-                r = -1;
+            r = kvm_handle_css_inst(cpu, run, ipa0, ipa1, ipb);
+            if (r == -1) {
+                dprintf("KVM: unhandled PRIV: 0x%x\n", ipa1);
             }
             break;
     }
-- 
1.8.1.4