[PATCH V4] KVM: PPC: BOOK3S: PR: Enable Little Endian PR guest

[Aneesh Kumar K.V]

This patch make sure we inherit the LE bit correctly in different case
so that we can run Little Endian distro in PR mode

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
---
Changes from V3:
* Address review comments.
  * rebase to new kernel so that intr_msr is moved instead of adding a new variable
  * Drop the lock since we are single threaded for PR KVM

 arch/powerpc/include/asm/kvm_host.h |  2 +-
 arch/powerpc/kernel/asm-offsets.c   |  2 +-
 arch/powerpc/kvm/book3s_64_mmu.c    |  2 +-
 arch/powerpc/kvm/book3s_pr.c        | 29 ++++++++++++++++++++++++++++-
 4 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 1eaea2dea174..d342f8efc843 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -562,6 +562,7 @@ struct kvm_vcpu_arch {
 #ifdef CONFIG_PPC_BOOK3S
 	ulong fault_dar;
 	u32 fault_dsisr;
+	unsigned long intr_msr;
 #endif
 
 #ifdef CONFIG_BOOKE
@@ -654,7 +655,6 @@ struct kvm_vcpu_arch {
 	spinlock_t tbacct_lock;
 	u64 busy_stolen;
 	u64 busy_preempt;
-	unsigned long intr_msr;
 #endif
 };
 
diff --git a/arch/powerpc/kernel/asm-offsets.c b/arch/powerpc/kernel/asm-offsets.c
index dba8140ebc20..6a4b77d197f3 100644
--- a/arch/powerpc/kernel/asm-offsets.c
+++ b/arch/powerpc/kernel/asm-offsets.c
@@ -493,7 +493,6 @@ int main(void)
 	DEFINE(VCPU_DAR, offsetof(struct kvm_vcpu, arch.shregs.dar));
 	DEFINE(VCPU_VPA, offsetof(struct kvm_vcpu, arch.vpa.pinned_addr));
 	DEFINE(VCPU_VPA_DIRTY, offsetof(struct kvm_vcpu, arch.vpa.dirty));
-	DEFINE(VCPU_INTR_MSR, offsetof(struct kvm_vcpu, arch.intr_msr));
 #endif
 #ifdef CONFIG_PPC_BOOK3S
 	DEFINE(VCPU_VCPUID, offsetof(struct kvm_vcpu, vcpu_id));
@@ -528,6 +527,7 @@ int main(void)
 	DEFINE(VCPU_SLB_NR, offsetof(struct kvm_vcpu, arch.slb_nr));
 	DEFINE(VCPU_FAULT_DSISR, offsetof(struct kvm_vcpu, arch.fault_dsisr));
 	DEFINE(VCPU_FAULT_DAR, offsetof(struct kvm_vcpu, arch.fault_dar));
+	DEFINE(VCPU_INTR_MSR, offsetof(struct kvm_vcpu, arch.intr_msr));
 	DEFINE(VCPU_LAST_INST, offsetof(struct kvm_vcpu, arch.last_inst));
 	DEFINE(VCPU_TRAP, offsetof(struct kvm_vcpu, arch.trap));
 	DEFINE(VCPU_CFAR, offsetof(struct kvm_vcpu, arch.cfar));
diff --git a/arch/powerpc/kvm/book3s_64_mmu.c b/arch/powerpc/kvm/book3s_64_mmu.c
index 83da1f868fd5..8231b83c493b 100644
--- a/arch/powerpc/kvm/book3s_64_mmu.c
+++ b/arch/powerpc/kvm/book3s_64_mmu.c
@@ -38,7 +38,7 @@
 
 static void kvmppc_mmu_book3s_64_reset_msr(struct kvm_vcpu *vcpu)
 {
-	kvmppc_set_msr(vcpu, MSR_SF);
+	kvmppc_set_msr(vcpu, vcpu->arch.intr_msr);
 }
 
 static struct kvmppc_slb *kvmppc_mmu_book3s_64_find_slbe(
diff --git a/arch/powerpc/kvm/book3s_pr.c b/arch/powerpc/kvm/book3s_pr.c
index f30cdfee800d..466273aca58b 100644
--- a/arch/powerpc/kvm/book3s_pr.c
+++ b/arch/powerpc/kvm/book3s_pr.c
@@ -249,7 +249,7 @@ static void kvmppc_recalc_shadow_msr(struct kvm_vcpu *vcpu)
 	ulong smsr = vcpu->arch.shared->msr;
 
 	/* Guest MSR values */
-	smsr &= MSR_FE0 | MSR_FE1 | MSR_SF | MSR_SE | MSR_BE;
+	smsr &= MSR_FE0 | MSR_FE1 | MSR_SF | MSR_SE | MSR_BE | MSR_LE;
 	/* Process MSR values */
 	smsr |= MSR_ME | MSR_RI | MSR_IR | MSR_DR | MSR_PR | MSR_EE;
 	/* External providers the guest reserved */
@@ -1118,6 +1118,15 @@ static int kvmppc_get_one_reg_pr(struct kvm_vcpu *vcpu, u64 id,
 	case KVM_REG_PPC_HIOR:
 		*val = get_reg_val(id, to_book3s(vcpu)->hior);
 		break;
+	case KVM_REG_PPC_LPCR:
+		/*
+		 * We are only interested in the LPCR_ILE bit
+		 */
+		if (vcpu->arch.intr_msr & MSR_LE)
+			*val = get_reg_val(id, LPCR_ILE);
+		else
+			*val = get_reg_val(id, 0);
+		break;
 	default:
 		r = -EINVAL;
 		break;
@@ -1126,6 +1135,20 @@ static int kvmppc_get_one_reg_pr(struct kvm_vcpu *vcpu, u64 id,
 	return r;
 }
 
+static void kvmppc_set_lpcr_pr(struct kvm_vcpu *vcpu, u64 new_lpcr)
+{
+	/*
+	 * If ILE (interrupt little-endian) has changed, update the
+	 * MSR_LE bit in the intr_msr for each vcpu in this vcore.
+	 */
+	if ((new_lpcr & LPCR_ILE) != (vcpu->arch.intr_msr & MSR_LE)) {
+		if (new_lpcr & LPCR_ILE)
+			vcpu->arch.intr_msr |= MSR_LE;
+		else
+			vcpu->arch.intr_msr &= ~MSR_LE;
+	}
+}
+
 static int kvmppc_set_one_reg_pr(struct kvm_vcpu *vcpu, u64 id,
 				 union kvmppc_one_reg *val)
 {
@@ -1136,6 +1159,9 @@ static int kvmppc_set_one_reg_pr(struct kvm_vcpu *vcpu, u64 id,
 		to_book3s(vcpu)->hior = set_reg_val(id, *val);
 		to_book3s(vcpu)->hior_explicit = true;
 		break;
+	case KVM_REG_PPC_LPCR:
+		kvmppc_set_lpcr_pr(vcpu, set_reg_val(id, *val));
+		break;
 	default:
 		r = -EINVAL;
 		break;
@@ -1188,6 +1214,7 @@ static struct kvm_vcpu *kvmppc_core_vcpu_create_pr(struct kvm *kvm,
 	vcpu->arch.pvr = 0x3C0301;
 	if (mmu_has_feature(MMU_FTR_1T_SEGMENT))
 		vcpu->arch.pvr = mfspr(SPRN_PVR);
+	vcpu->arch.intr_msr = MSR_SF;
 #else
 	/* default to book3s_32 (750) */
 	vcpu->arch.pvr = 0x84202;
-- 
1.9.1