[Qemu-devel] [PATCH 2/4] spapr: introduce a helper to compute the address of the HPT

[Greg Kurz <groug@kaod.org>]

The formula used to compute the address of the HPT allocated by QEMU is
open-coded in several places. This patch moves the magic to a dedicated
helper. While here, we also patch the callers to only pass the address
to KVM if we indeed have a userland HPT (ie, KVM PR).

Signed-off-by: Greg Kurz <groug@kaod.org>
---
 hw/ppc/spapr.c          |    9 +++++++++
 hw/ppc/spapr_cpu_core.c |   12 +++++++-----
 hw/ppc/spapr_hcall.c    |   14 ++++++++------
 include/hw/ppc/spapr.h  |    1 +
 4 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index caffa1276328..bf24c26b756d 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -1290,6 +1290,15 @@ static void spapr_store_hpte(PPCVirtualHypervisor *vhyp, hwaddr ptex,
     }
 }
 
+target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr)
+{
+    if (!spapr->htab) {
+        return 0;
+    }
+
+    return (target_ulong)(uintptr_t)spapr->htab | (spapr->htab_shift - 18);
+}
+
 int spapr_hpt_shift_for_ramsize(uint64_t ramsize)
 {
     int shift;
diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index 85037ef71e27..581eb4d92de9 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -93,11 +93,13 @@ static void spapr_cpu_reset(void *opaque)
      * HPT
      */
     if (kvm_enabled()) {
-        env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab
-            | (spapr->htab_shift - 18);
-        if (kvmppc_put_books_sregs(cpu) < 0) {
-            error_report("Unable to update SDR1 in KVM");
-            exit(1);
+        target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+        if (sdr1) {
+            env->spr[SPR_SDR1] = sdr1;
+            if (kvmppc_put_books_sregs(cpu) < 0) {
+                error_report("Unable to update SDR1 in KVM");
+                exit(1);
+            }
         }
     }
 }
diff --git a/hw/ppc/spapr_hcall.c b/hw/ppc/spapr_hcall.c
index 6ab8c188f381..06059b44ab40 100644
--- a/hw/ppc/spapr_hcall.c
+++ b/hw/ppc/spapr_hcall.c
@@ -735,9 +735,10 @@ static target_ulong h_resize_hpt_commit(PowerPCCPU *cpu,
 
         if (kvm_enabled()) {
             /* For KVM PR, update the HPT pointer */
-            target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
-                | (spapr->htab_shift - 18);
-            kvmppc_update_sdr1(sdr1);
+            target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+            if (sdr1) {
+                kvmppc_update_sdr1(sdr1);
+            }
         }
 
         pending->hpt = NULL; /* so it's not free()d */
@@ -1566,9 +1567,10 @@ static target_ulong h_client_architecture_support(PowerPCCPU *cpu,
             spapr_reallocate_hpt(spapr, maxshift, &error_fatal);
             if (kvm_enabled()) {
                 /* For KVM PR, update the HPT pointer */
-                target_ulong sdr1 = (target_ulong)(uintptr_t)spapr->htab
-                    | (spapr->htab_shift - 18);
-                kvmppc_update_sdr1(sdr1);
+                target_ulong sdr1 = spapr_get_hpt_pointer(spapr);
+                if (sdr1) {
+                    kvmppc_update_sdr1(sdr1);
+                }
             }
         }
     }
diff --git a/include/hw/ppc/spapr.h b/include/hw/ppc/spapr.h
index c1b365f56431..a1f5edc15018 100644
--- a/include/hw/ppc/spapr.h
+++ b/include/hw/ppc/spapr.h
@@ -709,4 +709,5 @@ void spapr_do_system_reset_on_cpu(CPUState *cs, run_on_cpu_data arg);
 int spapr_vcpu_id(PowerPCCPU *cpu);
 PowerPCCPU *spapr_find_cpu(int vcpu_id);
 
+target_ulong spapr_get_hpt_pointer(sPAPRMachineState *spapr);
 #endif /* HW_SPAPR_H */