[Qemu-devel] [PATCH] target-ppc: Fix htab_mask calculation

["Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>]

From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>

Correctly update the htab_mask using the return value of
KVM_PPC_ALLOCATE_HTAB ioctl. Also we don't update sdr1
on GET_SREGS for HV. So don't update htab_mask if sdr1
is found to be zero. Fix the pte index calculation to be
same as that found in the kernel

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
---
 hw/ppc/spapr.c          | 3 ++-
 target-ppc/mmu-hash64.c | 2 +-
 target-ppc/mmu_helper.c | 4 +++-
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 4a23b6a..4ce069b 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -717,7 +717,8 @@ static void spapr_cpu_reset(void *opaque)
 
     env->external_htab = (uint8_t *)spapr->htab;
     env->htab_base = -1;
-    env->htab_mask = HTAB_SIZE(spapr) - 1;
+    /* 128 (2**7) bytes in each HPTEG */
+    env->htab_mask = (1ULL << ((spapr)->htab_shift - 7)) - 1;
     env->spr[SPR_SDR1] = (target_ulong)(uintptr_t)spapr->htab |
         (spapr->htab_shift - 18);
 }
diff --git a/target-ppc/mmu-hash64.c b/target-ppc/mmu-hash64.c
index aeb4593..0deeae6 100644
--- a/target-ppc/mmu-hash64.c
+++ b/target-ppc/mmu-hash64.c
@@ -347,7 +347,7 @@ static hwaddr ppc_hash64_pteg_search(CPUPPCState *env, hwaddr hash,
     unsigned long pte_index;
     struct ppc_hash64_hpte_token *token;
 
-    pte_index = (hash * HPTES_PER_GROUP) & env->htab_mask;
+    pte_index = (hash & env->htab_mask) * HPTES_PER_GROUP;
     token = ppc_hash64_start_access(ppc_env_get_cpu(env), pte_index);
     if (!token) {
         return -1;
diff --git a/target-ppc/mmu_helper.c b/target-ppc/mmu_helper.c
index 04a840b..0322304 100644
--- a/target-ppc/mmu_helper.c
+++ b/target-ppc/mmu_helper.c
@@ -2025,7 +2025,9 @@ void ppc_store_sdr1(CPUPPCState *env, target_ulong value)
                         " stored in SDR1\n", htabsize);
                 htabsize = 28;
             }
-            env->htab_mask = (1ULL << (htabsize + 18)) - 1;
+            if (htabsize) {
+                env->htab_mask = (1ULL << (htabsize + 18)) - 1;
+            }
             env->htab_base = value & SDR_64_HTABORG;
         } else
 #endif /* defined(TARGET_PPC64) */
-- 
1.8.1.2