KVM: PPC: Make shared struct aka magic page guest endian

The shared (magic) page is a data structure that contains often used
supervisor privileged SPRs accessible via memory to the user to reduce
the number of exits we have to take to read/write them.

When we actually share this structure with the guest we have to maintain
it in guest endianness, because some of the patch tricks only work with
native endian load/store operations.

Since we only share the structure with either host or guest in little
endian on book3s_64 pr mode, we don't have to worry about booke or book3s hv.

For booke, the shared struct stays big endian. For book3s_64 hv we maintain
the struct in host native endian, since it never gets shared with the guest.

For book3s_64 pr we introduce a variable that tells us which endianness the
shared struct is in and route every access to it through helper inline
functions that evaluate this variable.

Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 12 insertions, 12 deletions

diff --git a/arch/powerpc/kvm/emulate.c b/arch/powerpc/kvm/emulate.c
index c2b887be2c29..da86d9ba3476 100644
--- a/arch/powerpc/kvm/emulate.c
+++ b/arch/powerpc/kvm/emulate.c
@@ -97,10 +97,10 @@ static int kvmppc_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs)
 
         switch (sprn) {
         case SPRN_SRR0:
-                vcpu->arch.shared->srr0 = spr_val;
+                kvmppc_set_srr0(vcpu, spr_val);
                 break;
         case SPRN_SRR1:
-                vcpu->arch.shared->srr1 = spr_val;
+                kvmppc_set_srr1(vcpu, spr_val);
                 break;
 
         /* XXX We need to context-switch the timebase for
@@ -114,16 +114,16 @@ static int kvmppc_emulate_mtspr(struct kvm_vcpu *vcpu, int sprn, int rs)
                 break;
 
         case SPRN_SPRG0:
-                vcpu->arch.shared->sprg0 = spr_val;
+                kvmppc_set_sprg0(vcpu, spr_val);
                 break;
         case SPRN_SPRG1:
-                vcpu->arch.shared->sprg1 = spr_val;
+                kvmppc_set_sprg1(vcpu, spr_val);
                 break;
         case SPRN_SPRG2:
-                vcpu->arch.shared->sprg2 = spr_val;
+                kvmppc_set_sprg2(vcpu, spr_val);
                 break;
         case SPRN_SPRG3:
-                vcpu->arch.shared->sprg3 = spr_val;
+                kvmppc_set_sprg3(vcpu, spr_val);
                 break;
 
         /* PIR can legally be written, but we ignore it */
@@ -150,10 +150,10 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt)
 
         switch (sprn) {
         case SPRN_SRR0:
-                spr_val = vcpu->arch.shared->srr0;
+                spr_val = kvmppc_get_srr0(vcpu);
                 break;
         case SPRN_SRR1:
-                spr_val = vcpu->arch.shared->srr1;
+                spr_val = kvmppc_get_srr1(vcpu);
                 break;
         case SPRN_PVR:
                 spr_val = vcpu->arch.pvr;
@@ -173,16 +173,16 @@ static int kvmppc_emulate_mfspr(struct kvm_vcpu *vcpu, int sprn, int rt)
                 break;
 
         case SPRN_SPRG0:
-                spr_val = vcpu->arch.shared->sprg0;
+                spr_val = kvmppc_get_sprg0(vcpu);
                 break;
         case SPRN_SPRG1:
-                spr_val = vcpu->arch.shared->sprg1;
+                spr_val = kvmppc_get_sprg1(vcpu);
                 break;
         case SPRN_SPRG2:
-                spr_val = vcpu->arch.shared->sprg2;
+                spr_val = kvmppc_get_sprg2(vcpu);
                 break;
         case SPRN_SPRG3:
-                spr_val = vcpu->arch.shared->sprg3;
+                spr_val = kvmppc_get_sprg3(vcpu);
                 break;
         /* Note: SPRG4-7 are user-readable, so we don't get
          * a trap. */