KVM: PPC: Book3s HV: Maintain separate guest and host views of R and C bits
This allows both the guest and the host to use the referenced (R) and
changed (C) bits in the guest hashed page table. The guest has a view
of R and C that is maintained in the guest_rpte field of the revmap
entry for the HPTE, and the host has a view that is maintained in the
rmap entry for the associated gfn.
Both view are updated from the guest HPT. If a bit (R or C) is zero
in either view, it will be initially set to zero in the HPTE (or HPTEs),
until set to 1 by hardware. When an HPTE is removed for any reason,
the R and C bits from the HPTE are ORed into both views. We have to
be careful to read the R and C bits from the HPTE after invalidating
it, but before unlocking it, in case of any late updates by the hardware.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Alexander Graf <agraf@suse.de>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 968f3aa..1cb6e52 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -200,8 +200,9 @@
* index in the guest HPT of a HPTE that points to the page.
*/
#define KVMPPC_RMAP_LOCK_BIT 63
-#define KVMPPC_RMAP_REF_BIT 33
-#define KVMPPC_RMAP_REFERENCED (1ul << KVMPPC_RMAP_REF_BIT)
+#define KVMPPC_RMAP_RC_SHIFT 32
+#define KVMPPC_RMAP_REFERENCED (HPTE_R_R << KVMPPC_RMAP_RC_SHIFT)
+#define KVMPPC_RMAP_CHANGED (HPTE_R_C << KVMPPC_RMAP_RC_SHIFT)
#define KVMPPC_RMAP_PRESENT 0x100000000ul
#define KVMPPC_RMAP_INDEX 0xfffffffful