arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremap
authorArd Biesheuvel <ard.biesheuvel@linaro.org>
Wed, 17 Sep 2014 21:56:18 +0000 (14:56 -0700)
committerChristoffer Dall <christoffer.dall@linaro.org>
Fri, 10 Oct 2014 11:07:37 +0000 (13:07 +0200)
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 <marc.zyngier@arm.com>
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
arch/arm/include/asm/kvm_mmu.h
arch/arm/kvm/mmu.c
arch/arm64/include/asm/kvm_mmu.h
virt/kvm/arm/vgic.c

index 3f688b458143503f3f369a2c89d3f2eabd3b0934..eaa6deac97b2568ae146847ea0076b61b9f02bea 100644 (file)
@@ -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);
 
index bb2e110e77c07e58239b3d2b1faedf07e699157a..a7eabd1c4287f01bb28d3ed7180f86521838c236 100644 (file)
@@ -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;
index a030d163840bf02e9eccd4828f54743dc4b8363b..e36171974d6adeccd03bbd3fdd185c058e1eda84 100644 (file)
@@ -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);
 
index 862967852d5afc7566f2ae20c027bb52183f25bc..382fb5a88b9c53950a96c811c8de0761ff0582b2 100644 (file)
@@ -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;