spapr, xics, xive: Match signatures for XICS and XIVE KVM connect routines

Both XICS and XIVE have routines to connect and disconnect KVM with
similar but not identical signatures.  This adjusts them to match
exactly, which will be useful for further cleanups later.

While we're there, we add an explicit return value to the connect path
to streamline error reporting in the callers.  We remove error
reporting the disconnect path.  In the XICS case this wasn't used at
all.  In the XIVE case the only error case was if the KVM device was
set up, but KVM didn't have the capability to do so which is pretty
obviously impossible.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>

hw/intc/spapr_xive_kvm.c

@@ -740,8 +740,9 @@ static void *kvmppc_xive_mmap(SpaprXive *xive, int pgoff, size_t len,
  * All the XIVE memory regions are now backed by mappings from the KVM
  * XIVE device.
  */
-void kvmppc_xive_connect(SpaprXive *xive, Error **errp)
+int kvmppc_xive_connect(SpaprInterruptController *intc, Error **errp)
 {
+    SpaprXive *xive = SPAPR_XIVE(intc);
     XiveSource *xsrc = &xive->source;
     Error *local_err = NULL;
     size_t esb_len = (1ull << xsrc->esb_shift) * xsrc->nr_irqs;
@@ -753,19 +754,19 @@ void kvmppc_xive_connect(SpaprXive *xive, Error **errp)
      * rebooting under the XIVE-only interrupt mode.
      */
     if (xive->fd != -1) {
-        return;
+        return 0;
     }
 
     if (!kvmppc_has_cap_xive()) {
         error_setg(errp, "IRQ_XIVE capability must be present for KVM");
-        return;
+        return -1;
     }
 
     /* First, create the KVM XIVE device */
     xive->fd = kvm_create_device(kvm_state, KVM_DEV_TYPE_XIVE, false);
     if (xive->fd < 0) {
         error_setg_errno(errp, -xive->fd, "XIVE: error creating KVM device");
-        return;
+        return -1;
     }
 
     /*
@@ -821,15 +822,17 @@ void kvmppc_xive_connect(SpaprXive *xive, Error **errp)
     kvm_kernel_irqchip = true;
     kvm_msi_via_irqfd_allowed = true;
     kvm_gsi_direct_mapping = true;
-    return;
+    return 0;
 
 fail:
     error_propagate(errp, local_err);
-    kvmppc_xive_disconnect(xive, NULL);
+    kvmppc_xive_disconnect(intc);
+    return -1;
 }
 
-void kvmppc_xive_disconnect(SpaprXive *xive, Error **errp)
+void kvmppc_xive_disconnect(SpaprInterruptController *intc)
 {
+    SpaprXive *xive = SPAPR_XIVE(intc);
     XiveSource *xsrc;
     size_t esb_len;
 
@@ -838,11 +841,6 @@ void kvmppc_xive_disconnect(SpaprXive *xive, Error **errp)
         return;
     }
 
-    if (!kvmppc_has_cap_xive()) {
-        error_setg(errp, "IRQ_XIVE capability must be present for KVM");
-        return;
-    }
-
     /* Clear the KVM mapping */
     xsrc = &xive->source;
     esb_len = (1ull << xsrc->esb_shift) * xsrc->nr_irqs;

hw/intc/xics_kvm.c

@@ -342,8 +342,9 @@ void ics_kvm_set_irq(ICSState *ics, int srcno, int val)
     }
 }
 
-int xics_kvm_connect(SpaprMachineState *spapr, Error **errp)
+int xics_kvm_connect(SpaprInterruptController *intc, Error **errp)
 {
+    ICSState *ics = ICS_SPAPR(intc);
     int rc;
     CPUState *cs;
     Error *local_err = NULL;
@@ -413,7 +414,7 @@ int xics_kvm_connect(SpaprMachineState *spapr, Error **errp)
     }
 
     /* Update the KVM sources */
-    ics_set_kvm_state(spapr->ics, &local_err);
+    ics_set_kvm_state(ics, &local_err);
     if (local_err) {
         goto fail;
     }
@@ -431,11 +432,11 @@ int xics_kvm_connect(SpaprMachineState *spapr, Error **errp)
 
 fail:
     error_propagate(errp, local_err);
-    xics_kvm_disconnect(spapr, NULL);
+    xics_kvm_disconnect(intc);
     return -1;
 }
 
-void xics_kvm_disconnect(SpaprMachineState *spapr, Error **errp)
+void xics_kvm_disconnect(SpaprInterruptController *intc)
 {
     /*
      * Only on P9 using the XICS-on XIVE KVM device:

hw/ppc/spapr_irq.c

@@ -124,7 +124,7 @@ static void spapr_irq_reset_xics(SpaprMachineState *spapr, Error **errp)
 static void spapr_irq_init_kvm_xics(SpaprMachineState *spapr, Error **errp)
 {
     if (kvm_enabled()) {
-        xics_kvm_connect(spapr, errp);
+        xics_kvm_connect(SPAPR_INTC(spapr->ics), errp);
     }
 }
 
@@ -173,7 +173,7 @@ static void spapr_irq_reset_xive(SpaprMachineState *spapr, Error **errp)
 static void spapr_irq_init_kvm_xive(SpaprMachineState *spapr, Error **errp)
 {
     if (kvm_enabled()) {
-        kvmppc_xive_connect(spapr->xive, errp);
+        kvmppc_xive_connect(SPAPR_INTC(spapr->xive), errp);
     }
 }
 
@@ -215,7 +215,7 @@ static int spapr_irq_post_load_dual(SpaprMachineState *spapr, int version_id)
      */
     if (spapr_ovec_test(spapr->ov5_cas, OV5_XIVE_EXPLOIT)) {
         if (kvm_irqchip_in_kernel()) {
-            xics_kvm_disconnect(spapr, &error_fatal);
+            xics_kvm_disconnect(SPAPR_INTC(spapr->ics));
         }
         spapr_irq_xive.reset(spapr, &error_fatal);
     }
@@ -225,8 +225,6 @@ static int spapr_irq_post_load_dual(SpaprMachineState *spapr, int version_id)
 
 static void spapr_irq_reset_dual(SpaprMachineState *spapr, Error **errp)
 {
-    Error *local_err = NULL;
-
     /*
      * Deactivate the XIVE MMIOs. The XIVE backend will reenable them
      * if selected.
@@ -235,18 +233,8 @@ static void spapr_irq_reset_dual(SpaprMachineState *spapr, Error **errp)
 
     /* Destroy all KVM devices */
     if (kvm_irqchip_in_kernel()) {
-        xics_kvm_disconnect(spapr, &local_err);
-        if (local_err) {
-            error_propagate(errp, local_err);
-            error_prepend(errp, "KVM XICS disconnect failed: ");
-            return;
-        }
-        kvmppc_xive_disconnect(spapr->xive, &local_err);
-        if (local_err) {
-            error_propagate(errp, local_err);
-            error_prepend(errp, "KVM XIVE disconnect failed: ");
-            return;
-        }
+        xics_kvm_disconnect(SPAPR_INTC(spapr->ics));
+        kvmppc_xive_disconnect(SPAPR_INTC(spapr->xive));
     }
 
     spapr_irq_current(spapr)->reset(spapr, errp);

include/hw/ppc/spapr_xive.h

@@ -68,8 +68,8 @@ int spapr_xive_end_to_target(uint8_t end_blk, uint32_t end_idx,
 /*
  * KVM XIVE device helpers
  */
-void kvmppc_xive_connect(SpaprXive *xive, Error **errp);
-void kvmppc_xive_disconnect(SpaprXive *xive, Error **errp);
+int kvmppc_xive_connect(SpaprInterruptController *intc, Error **errp);
+void kvmppc_xive_disconnect(SpaprInterruptController *intc);
 void kvmppc_xive_reset(SpaprXive *xive, Error **errp);
 void kvmppc_xive_set_source_config(SpaprXive *xive, uint32_t lisn, XiveEAS *eas,
                                    Error **errp);

include/hw/ppc/xics_spapr.h

@@ -32,8 +32,8 @@
 #define TYPE_ICS_SPAPR "ics-spapr"
 #define ICS_SPAPR(obj) OBJECT_CHECK(ICSState, (obj), TYPE_ICS_SPAPR)
 
-int xics_kvm_connect(SpaprMachineState *spapr, Error **errp);
-void xics_kvm_disconnect(SpaprMachineState *spapr, Error **errp);
+int xics_kvm_connect(SpaprInterruptController *intc, Error **errp);
+void xics_kvm_disconnect(SpaprInterruptController *intc);
 bool xics_kvm_has_broken_disconnect(SpaprMachineState *spapr);
 
 #endif /* XICS_SPAPR_H */