From 840f4bfbe03f1ce94ade8fdf84e8cd925ef15a48 Mon Sep 17 00:00:00 2001 From: Laszlo Ersek Date: Mon, 17 Nov 2014 14:58:52 +0000 Subject: [PATCH] arm, arm64: KVM: allow forced dcache flush on page faults To allow handling of incoherent memslots in a subsequent patch, this patch adds a paramater 'ipa_uncached' to cache_coherent_guest_page() so that we can instruct it to flush the page's contents to DRAM even if the guest has caching globally enabled. Signed-off-by: Laszlo Ersek Signed-off-by: Ard Biesheuvel Signed-off-by: Marc Zyngier --- arch/arm/include/asm/kvm_mmu.h | 5 +++-- arch/arm/kvm/mmu.c | 9 +++++++-- arch/arm64/include/asm/kvm_mmu.h | 5 +++-- 3 files changed, 13 insertions(+), 6 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index acb0d5712716..f867060035ec 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -161,9 +161,10 @@ static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu) } static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, - unsigned long size) + unsigned long size, + bool ipa_uncached) { - if (!vcpu_has_cache_enabled(vcpu)) + if (!vcpu_has_cache_enabled(vcpu) || ipa_uncached) kvm_flush_dcache_to_poc((void *)hva, size); /* diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index b007438242e2..cb924c6d56a6 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -852,6 +852,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, struct vm_area_struct *vma; pfn_t pfn; pgprot_t mem_type = PAGE_S2; + bool fault_ipa_uncached; write_fault = kvm_is_write_fault(vcpu); if (fault_status == FSC_PERM && !write_fault) { @@ -918,6 +919,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (!hugetlb && !force_pte) hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa); + fault_ipa_uncached = false; + if (hugetlb) { pmd_t new_pmd = pfn_pmd(pfn, mem_type); new_pmd = pmd_mkhuge(new_pmd); @@ -925,7 +928,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, kvm_set_s2pmd_writable(&new_pmd); kvm_set_pfn_dirty(pfn); } - coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE); + coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE, + fault_ipa_uncached); ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd); } else { pte_t new_pte = pfn_pte(pfn, mem_type); @@ -933,7 +937,8 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, kvm_set_s2pte_writable(&new_pte); kvm_set_pfn_dirty(pfn); } - coherent_cache_guest_page(vcpu, hva, PAGE_SIZE); + coherent_cache_guest_page(vcpu, hva, PAGE_SIZE, + fault_ipa_uncached); ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, pgprot_val(mem_type) == pgprot_val(PAGE_S2_DEVICE)); } diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 0caf7a59f6a1..123b521a9908 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -243,9 +243,10 @@ static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu) } static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva, - unsigned long size) + unsigned long size, + bool ipa_uncached) { - if (!vcpu_has_cache_enabled(vcpu)) + if (!vcpu_has_cache_enabled(vcpu) || ipa_uncached) kvm_flush_dcache_to_poc((void *)hva, size); if (!icache_is_aliasing()) { /* PIPT */