KVM: PPC: Improve split mode
When in split mode, instruction relocation and data relocation are not equal.
So far we implemented this mode by reserving a special pseudo-VSID for the
two cases and flushing all PTEs when going into split mode, which is slow.
Unfortunately 32bit Linux and Mac OS X use split mode extensively. So to not
slow down things too much, I came up with a different idea: Mark the split
mode with a bit in the VSID and then treat it like any other segment.
This means we can just flush the shadow segment cache, but keep the PTEs
intact. I verified that this works with ppc32 Linux and Mac OS X 10.4
guests and does speed them up.
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index 5d3bd0c..6f74d93 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -100,11 +100,10 @@
#define CONTEXT_GUEST 1
#define CONTEXT_GUEST_END 2
-#define VSID_REAL_DR 0x7ffffffffff00000ULL
-#define VSID_REAL_IR 0x7fffffffffe00000ULL
-#define VSID_SPLIT_MASK 0x7fffffffffe00000ULL
-#define VSID_REAL 0x7fffffffffc00000ULL
-#define VSID_BAT 0x7fffffffffb00000ULL
+#define VSID_REAL 0x1fffffffffc00000ULL
+#define VSID_BAT 0x1fffffffffb00000ULL
+#define VSID_REAL_DR 0x2000000000000000ULL
+#define VSID_REAL_IR 0x4000000000000000ULL
#define VSID_PR 0x8000000000000000ULL
extern void kvmppc_mmu_pte_flush(struct kvm_vcpu *vcpu, ulong ea, ulong ea_mask);