From: Ard Biesheuvel <[email protected]> Add support for read-only MMIO passthrough mappings by adding a 'writable' parameter to kvm_phys_addr_ioremap. For the moment, mappings will be read-write even if 'writable' is false, but once the definition of PAGE_S2_DEVICE gets changed, those mappings will be created read-only.
Acked-by: Marc Zyngier <[email protected]> Signed-off-by: Ard Biesheuvel <[email protected]> Signed-off-by: Christoffer Dall <[email protected]> --- arch/arm/include/asm/kvm_mmu.h | 2 +- arch/arm/kvm/mmu.c | 5 ++++- arch/arm64/include/asm/kvm_mmu.h | 2 +- virt/kvm/arm/vgic.c | 3 ++- 4 files changed, 8 insertions(+), 4 deletions(-) diff --git a/arch/arm/include/asm/kvm_mmu.h b/arch/arm/include/asm/kvm_mmu.h index 3f688b4..eaa6dea 100644 --- a/arch/arm/include/asm/kvm_mmu.h +++ b/arch/arm/include/asm/kvm_mmu.h @@ -50,7 +50,7 @@ void free_hyp_pgds(void); int kvm_alloc_stage2_pgd(struct kvm *kvm); void kvm_free_stage2_pgd(struct kvm *kvm); int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, - phys_addr_t pa, unsigned long size); + phys_addr_t pa, unsigned long size, bool writable); int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run); diff --git a/arch/arm/kvm/mmu.c b/arch/arm/kvm/mmu.c index bb2e110..a7eabd1 100644 --- a/arch/arm/kvm/mmu.c +++ b/arch/arm/kvm/mmu.c @@ -674,7 +674,7 @@ static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache, * @size: The size of the mapping */ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, - phys_addr_t pa, unsigned long size) + phys_addr_t pa, unsigned long size, bool writable) { phys_addr_t addr, end; int ret = 0; @@ -687,6 +687,9 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) { pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE); + if (writable) + kvm_set_s2pte_writable(&pte); + ret = mmu_topup_memory_cache(&cache, 2, 2); if (ret) goto out; diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index a030d16..e361719 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -77,7 +77,7 @@ void free_hyp_pgds(void); int kvm_alloc_stage2_pgd(struct kvm *kvm); void kvm_free_stage2_pgd(struct kvm *kvm); int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, - phys_addr_t pa, unsigned long size); + phys_addr_t pa, unsigned long size, bool writable); int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run); diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 8629678..382fb5a 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1899,7 +1899,8 @@ int kvm_vgic_init(struct kvm *kvm) } ret = kvm_phys_addr_ioremap(kvm, kvm->arch.vgic.vgic_cpu_base, - vgic->vcpu_base, KVM_VGIC_V2_CPU_SIZE); + vgic->vcpu_base, KVM_VGIC_V2_CPU_SIZE, + true); if (ret) { kvm_err("Unable to remap VGIC CPU to VCPU\n"); goto out; -- 2.1.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
