Commit 0eb802b3 authored by Vincent Donnefort's avatar Vincent Donnefort Committed by Marc Zyngier
Browse files

KVM: arm64: Add a range to __pkvm_host_wrprotect_guest() 



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: default avatarVincent Donnefort <vdonnefort@google.com>
Link: https://lore.kernel.org/r/20250521124834.1070650-6-vdonnefort@google.com


Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
parent f28f1d02

arch/arm64/kvm/hyp/include/nvhe/mem_protect.h

+1 −1
Original line number Diff line number Diff line
@@ -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);

arch/arm64/kvm/hyp/nvhe/hyp-main.c

+2 −1
Original line number Diff line number Diff line
@@ -310,6 +310,7 @@ 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;
@@ -320,7 +321,7 @@ 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;

arch/arm64/kvm/hyp/nvhe/mem_protect.c

+13 −9
Original line number Diff line number Diff line
@@ -1052,7 +1052,7 @@ 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;
@@ -1063,7 +1063,7 @@ 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();
@@ -1083,7 +1083,7 @@ 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);
@@ -1091,17 +1091,21 @@ 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;
@@ -1115,7 +1119,7 @@ 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);
@@ -1131,7 +1135,7 @@ 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);

arch/arm64/kvm/pkvm.c

+1 −1
Original line number Diff line number Diff line
@@ -409,7 +409,7 @@ 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;

	}