mmu-hash*: Add hash pte load/store helpers

On real hardware the ppc hash page table is stored in memory; accordingly
our mmu emulation code can read a hash page table in guest memory.  But,
when paravirtualized under PAPR, the real hash page table is in host
memory, accessible to the guest only via hypercalls.  We model this by
also allowing the MMU emulation code to access a specially allocated hash
page table outside the guest's memory image. At present these two options
are implemented with some ugly conditionals at each access point in the mmu
emulation code.  In the implementation of the PAPR hypercalls, we assume
the external hash table.

This patch cleans things up by adding helpers to load and store from the
hash table for both 32-bit and 64-bit hash mmus.  The 64-bit versions
handle both the in-guest-memory and outside guest memory cases.  The 32-bit
versions only handle the in-guest-memory case since no 32-bit systems can
have an external hash table at present.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 40 insertions, 0 deletions

diff --git a/target-ppc/mmu-hash64.h b/target-ppc/mmu-hash64.h
index 80b86d91ae..84576c0648 100644
--- a/target-ppc/mmu-hash64.h
+++ b/target-ppc/mmu-hash64.h
@@ -73,6 +73,46 @@ int ppc_hash64_handle_mmu_fault(CPUPPCState *env, target_ulong address, int rw,
 #define HPTE64_V_1TB_SEG        0x4000000000000000ULL
 #define HPTE64_V_VRMA_MASK      0x4001ffffff000000ULL
 
+static inline target_ulong ppc_hash64_load_hpte0(CPUPPCState *env,
+                                                 hwaddr pte_offset)
+{
+    if (env->external_htab) {
+        return  ldq_p(env->external_htab + pte_offset);
+    } else {
+        return ldq_phys(env->htab_base + pte_offset);
+    }
+}
+
+static inline target_ulong ppc_hash64_load_hpte1(CPUPPCState *env,
+                                                 hwaddr pte_offset)
+{
+    if (env->external_htab) {
+        return ldq_p(env->external_htab + pte_offset + HASH_PTE_SIZE_64/2);
+    } else {
+        return ldq_phys(env->htab_base + pte_offset + HASH_PTE_SIZE_64/2);
+    }
+}
+
+static inline void ppc_hash64_store_hpte0(CPUPPCState *env,
+                                          hwaddr pte_offset, target_ulong pte0)
+{
+    if (env->external_htab) {
+        stq_p(env->external_htab + pte_offset, pte0);
+    } else {
+        stq_phys(env->htab_base + pte_offset, pte0);
+    }
+}
+
+static inline void ppc_hash64_store_hpte1(CPUPPCState *env,
+                                          hwaddr pte_offset, target_ulong pte1)
+{
+    if (env->external_htab) {
+        stq_p(env->external_htab + pte_offset + HASH_PTE_SIZE_64/2, pte1);
+    } else {
+        stq_phys(env->htab_base + pte_offset + HASH_PTE_SIZE_64/2, pte1);
+    }
+}
+
 #endif /* CONFIG_USER_ONLY */
 
 #endif /* !defined (__MMU_HASH64_H__) */