[PATCH v2 4/9] KVM: arm64: Add a range to __pkvm_host_wrprotect_guest()
From: Vincent Donnefort <hidden>
Date: 2025-03-06 11:00:55
Also in:
kvmarm, lkml
Subsystem:
arm64 port (aarch64 architecture), kernel virtual machine for arm64 (kvm/arm64), the rest · Maintainers:
Catalin Marinas, Will Deacon, Marc Zyngier, Oliver Upton, Linus Torvalds
In preparation for supporting stage-2 huge mappings for np-guest. Add a nr_pages argument to the __pkvm_host_wrprotect_guest hypercall. This range supports only two values: 1 or PMD_SIZE / PAGE_SIZE (that is 512 on a 4K-pages system). Signed-off-by: Vincent Donnefort <redacted>
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
index 343569e4bdeb..ad6131033114 100644
--- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h
+++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h@@ -43,8 +43,8 @@ int __pkvm_host_share_guest(u64 pfn, u64 gfn, u64 nr_pages, struct pkvm_hyp_vcpu enum kvm_pgtable_prot prot); int __pkvm_host_unshare_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *hyp_vm); int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enum kvm_pgtable_prot prot); -int __pkvm_host_wrprotect_guest(u64 gfn, struct pkvm_hyp_vm *hyp_vm); int __pkvm_host_test_clear_young_guest(u64 gfn, bool mkold, struct pkvm_hyp_vm *vm); +int __pkvm_host_wrprotect_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *hyp_vm); int __pkvm_host_mkyoung_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu); bool addr_is_memory(phys_addr_t phys);
diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c
index 7f22d104c1f1..e13771a67827 100644
--- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c
+++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c@@ -314,6 +314,7 @@ static void handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context *host_ctxt { DECLARE_REG(pkvm_handle_t, handle, host_ctxt, 1); DECLARE_REG(u64, gfn, host_ctxt, 2); + DECLARE_REG(u64, nr_pages, host_ctxt, 3); struct pkvm_hyp_vm *hyp_vm; int ret = -EINVAL;
@@ -324,7 +325,7 @@ static void handle___pkvm_host_wrprotect_guest(struct kvm_cpu_context *host_ctxt if (!hyp_vm) goto out; - ret = __pkvm_host_wrprotect_guest(gfn, hyp_vm); + ret = __pkvm_host_wrprotect_guest(gfn, nr_pages, hyp_vm); put_pkvm_hyp_vm(hyp_vm); out: cpu_reg(host_ctxt, 1) = ret;
diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvhe/mem_protect.c
index 7b9b112e3ebf..e113ece1b759 100644
--- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c
+++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c@@ -1065,7 +1065,7 @@ int __pkvm_host_unshare_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *vm) return ret; } -static void assert_host_shared_guest(struct pkvm_hyp_vm *vm, u64 ipa) +static void assert_host_shared_guest(struct pkvm_hyp_vm *vm, u64 ipa, u64 size) { u64 phys; int ret;
@@ -1076,7 +1076,7 @@ static void assert_host_shared_guest(struct pkvm_hyp_vm *vm, u64 ipa) host_lock_component(); guest_lock_component(vm); - ret = __check_host_shared_guest(vm, &phys, ipa, PAGE_SIZE); + ret = __check_host_shared_guest(vm, &phys, ipa, size); guest_unlock_component(vm); host_unlock_component();
@@ -1096,7 +1096,7 @@ int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enum kvm_ if (prot & ~KVM_PGTABLE_PROT_RWX) return -EINVAL; - assert_host_shared_guest(vm, ipa); + assert_host_shared_guest(vm, ipa, PAGE_SIZE); guest_lock_component(vm); ret = kvm_pgtable_stage2_relax_perms(&vm->pgt, ipa, prot, 0); guest_unlock_component(vm);
@@ -1104,17 +1104,21 @@ int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enum kvm_ return ret; } -int __pkvm_host_wrprotect_guest(u64 gfn, struct pkvm_hyp_vm *vm) +int __pkvm_host_wrprotect_guest(u64 gfn, u64 nr_pages, struct pkvm_hyp_vm *vm) { - u64 ipa = hyp_pfn_to_phys(gfn); + u64 size, ipa = hyp_pfn_to_phys(gfn); int ret; if (pkvm_hyp_vm_is_protected(vm)) return -EPERM; - assert_host_shared_guest(vm, ipa); + ret = __guest_check_transition_size(0, ipa, nr_pages, &size); + if (ret) + return ret; + + assert_host_shared_guest(vm, ipa, size); guest_lock_component(vm); - ret = kvm_pgtable_stage2_wrprotect(&vm->pgt, ipa, PAGE_SIZE); + ret = kvm_pgtable_stage2_wrprotect(&vm->pgt, ipa, size); guest_unlock_component(vm); return ret;
@@ -1128,7 +1132,7 @@ int __pkvm_host_test_clear_young_guest(u64 gfn, bool mkold, struct pkvm_hyp_vm * if (pkvm_hyp_vm_is_protected(vm)) return -EPERM; - assert_host_shared_guest(vm, ipa); + assert_host_shared_guest(vm, ipa, PAGE_SIZE); guest_lock_component(vm); ret = kvm_pgtable_stage2_test_clear_young(&vm->pgt, ipa, PAGE_SIZE, mkold); guest_unlock_component(vm);
@@ -1144,7 +1148,7 @@ int __pkvm_host_mkyoung_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu) if (pkvm_hyp_vm_is_protected(vm)) return -EPERM; - assert_host_shared_guest(vm, ipa); + assert_host_shared_guest(vm, ipa, PAGE_SIZE); guest_lock_component(vm); kvm_pgtable_stage2_mkyoung(&vm->pgt, ipa, 0); guest_unlock_component(vm);
diff --git a/arch/arm64/kvm/pkvm.c b/arch/arm64/kvm/pkvm.c
index b65fcf245fc9..3ea92bb79e8c 100644
--- a/arch/arm64/kvm/pkvm.c
+++ b/arch/arm64/kvm/pkvm.c@@ -404,7 +404,7 @@ int pkvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size) lockdep_assert_held(&kvm->mmu_lock); for_each_mapping_in_range_safe(pgt, addr, addr + size, mapping) { - ret = kvm_call_hyp_nvhe(__pkvm_host_wrprotect_guest, handle, mapping->gfn); + ret = kvm_call_hyp_nvhe(__pkvm_host_wrprotect_guest, handle, mapping->gfn, 1); if (WARN_ON(ret)) break; }
--
2.48.1.711.g2feabab25a-goog