[PATCH 4/5] KVM: PPC: Add cache flush on page map

[Alexander Graf <agraf@suse.de>]

When we map a page that wasn't icache cleared before, do so when first
mapping it in KVM using the same information bits as the Linux mapping
logic. That way we are 100% sure that any page we map does not have stale
entries in the icache.

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

---

v1 -> v2:

  - move code to arch/powerpc
---
 arch/powerpc/include/asm/kvm_host.h   |    1 +
 arch/powerpc/include/asm/kvm_ppc.h    |   12 ++++++++++++
 arch/powerpc/kvm/book3s_32_mmu_host.c |    3 +++
 arch/powerpc/kvm/book3s_64_mmu_host.c |    2 ++
 arch/powerpc/kvm/e500_tlb.c           |    3 +++
 arch/powerpc/mm/mem.c                 |    1 +
 6 files changed, 22 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index ed75bc9..f5c289b 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -33,6 +33,7 @@
 #include <asm/kvm_asm.h>
 #include <asm/processor.h>
 #include <asm/page.h>
+#include <asm/cacheflush.h>
 
 #define KVM_MAX_VCPUS		NR_CPUS
 #define KVM_MAX_VCORES		NR_CPUS
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index c38e824..88de314 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -220,4 +220,16 @@ void kvmppc_claim_lpid(long lpid);
 void kvmppc_free_lpid(long lpid);
 void kvmppc_init_lpid(unsigned long nr_lpids);
 
+static inline void kvmppc_mmu_flush_icache(pfn_t pfn)
+{
+	/* Clear i-cache for new pages */
+	struct page *page;
+	page = pfn_to_page(pfn);
+	if (!test_bit(PG_arch_1, &page->flags)) {
+		flush_dcache_icache_page(page);
+		set_bit(PG_arch_1, &page->flags);
+	}
+}
+
+
 #endif /* __POWERPC_KVM_PPC_H__ */
diff --git a/arch/powerpc/kvm/book3s_32_mmu_host.c b/arch/powerpc/kvm/book3s_32_mmu_host.c
index f922c29..837f13e 100644
--- a/arch/powerpc/kvm/book3s_32_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_32_mmu_host.c
@@ -211,6 +211,9 @@ next_pteg:
 		pteg1 |= PP_RWRX;
 	}
 
+	if (orig_pte->may_execute)
+		kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);
+
 	local_irq_disable();
 
 	if (pteg[rr]) {
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
index 10fc8ec..0688b6b 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -126,6 +126,8 @@ int kvmppc_mmu_map_page(struct kvm_vcpu *vcpu, struct kvmppc_pte *orig_pte)
 
 	if (!orig_pte->may_execute)
 		rflags |= HPTE_R_N;
+	else
+		kvmppc_mmu_flush_icache(hpaddr >> PAGE_SHIFT);
 
 	hash = hpt_hash(va, PTE_SIZE, MMU_SEGSIZE_256M);
 
diff --git a/arch/powerpc/kvm/e500_tlb.c b/arch/powerpc/kvm/e500_tlb.c
index c439754..56bc92c 100644
--- a/arch/powerpc/kvm/e500_tlb.c
+++ b/arch/powerpc/kvm/e500_tlb.c
@@ -544,6 +544,9 @@ static inline void kvmppc_e500_shadow_map(struct kvmppc_vcpu_e500 *vcpu_e500,
 	kvmppc_e500_setup_stlbe(&vcpu_e500->vcpu, gtlbe, tsize,
 				ref, gvaddr, stlbe);
 
+	/* Clear i-cache for new pages */
+	kvmppc_mmu_flush_icache(pfn);
+
 	/* Drop refcount on page, so that mmu notifiers can clear it */
 	kvm_release_pfn_clean(pfn);
 }
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index baaafde..fbdad0e 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -469,6 +469,7 @@ void flush_dcache_icache_page(struct page *page)
 	__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
 #endif
 }
+EXPORT_SYMBOL(flush_dcache_icache_page);
 
 void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
 {
-- 
1.6.0.2