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It will be used later once we start allowing RO memslots and dirty logging. Tested-by: Fuad Tabba Reviewed-by: Fuad Tabba Signed-off-by: Quentin Perret --- arch/arm64/include/asm/kvm_asm.h | 1 + arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 1 + arch/arm64/kvm/hyp/nvhe/hyp-main.c | 20 ++++++++++++++++ arch/arm64/kvm/hyp/nvhe/mem_protect.c | 23 +++++++++++++++++++ 4 files changed, 45 insertions(+) diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_= asm.h index 0b6c4d325134..66ee8542dcc9 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -67,6 +67,7 @@ enum __kvm_host_smccc_func { __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_hyp, __KVM_HOST_SMCCC_FUNC___pkvm_host_share_guest, __KVM_HOST_SMCCC_FUNC___pkvm_host_unshare_guest, + __KVM_HOST_SMCCC_FUNC___pkvm_host_relax_perms_guest, __KVM_HOST_SMCCC_FUNC___kvm_adjust_pc, __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run, __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context, diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm= /hyp/include/nvhe/mem_protect.h index e6d080b71779..181aec2d5bc1 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h @@ -42,6 +42,7 @@ int __pkvm_host_unshare_ffa(u64 pfn, u64 nr_pages); int __pkvm_host_share_guest(u64 pfn, u64 gfn, struct pkvm_hyp_vcpu *vcpu, enum kvm_pgtable_prot prot); int __pkvm_host_unshare_guest(u64 gfn, struct pkvm_hyp_vm *hyp_vm); +int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enu= m kvm_pgtable_prot prot); =20 bool addr_is_memory(phys_addr_t phys); int host_stage2_idmap_locked(phys_addr_t addr, u64 size, enum kvm_pgtable_= prot prot); diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/h= yp-main.c index 3c3a27c985a2..287e4ee93ef2 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-main.c +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -264,6 +264,25 @@ static void handle___pkvm_host_unshare_guest(struct kv= m_cpu_context *host_ctxt) cpu_reg(host_ctxt, 1) =3D ret; } =20 +static void handle___pkvm_host_relax_perms_guest(struct kvm_cpu_context *h= ost_ctxt) +{ + DECLARE_REG(u64, gfn, host_ctxt, 1); + DECLARE_REG(enum kvm_pgtable_prot, prot, host_ctxt, 2); + struct pkvm_hyp_vcpu *hyp_vcpu; + int ret =3D -EINVAL; + + if (!is_protected_kvm_enabled()) + goto out; + + hyp_vcpu =3D pkvm_get_loaded_hyp_vcpu(); + if (!hyp_vcpu || pkvm_hyp_vcpu_is_protected(hyp_vcpu)) + goto out; + + ret =3D __pkvm_host_relax_perms_guest(gfn, hyp_vcpu, prot); +out: + cpu_reg(host_ctxt, 1) =3D ret; +} + static void handle___kvm_adjust_pc(struct kvm_cpu_context *host_ctxt) { DECLARE_REG(struct kvm_vcpu *, vcpu, host_ctxt, 1); @@ -475,6 +494,7 @@ static const hcall_t host_hcall[] =3D { HANDLE_FUNC(__pkvm_host_unshare_hyp), HANDLE_FUNC(__pkvm_host_share_guest), HANDLE_FUNC(__pkvm_host_unshare_guest), + HANDLE_FUNC(__pkvm_host_relax_perms_guest), HANDLE_FUNC(__kvm_adjust_pc), HANDLE_FUNC(__kvm_vcpu_run), HANDLE_FUNC(__kvm_flush_vm_context), diff --git a/arch/arm64/kvm/hyp/nvhe/mem_protect.c b/arch/arm64/kvm/hyp/nvh= e/mem_protect.c index 30243b7922f1..aa8e0408aebb 100644 --- a/arch/arm64/kvm/hyp/nvhe/mem_protect.c +++ b/arch/arm64/kvm/hyp/nvhe/mem_protect.c @@ -1488,3 +1488,26 @@ int __pkvm_host_unshare_guest(u64 gfn, struct pkvm_h= yp_vm *vm) =20 return ret; } + +int __pkvm_host_relax_perms_guest(u64 gfn, struct pkvm_hyp_vcpu *vcpu, enu= m kvm_pgtable_prot prot) +{ + struct pkvm_hyp_vm *vm =3D pkvm_hyp_vcpu_to_hyp_vm(vcpu); + u64 ipa =3D hyp_pfn_to_phys(gfn); + u64 phys; + int ret; + + if (prot & ~KVM_PGTABLE_PROT_RWX) + return -EINVAL; + + host_lock_component(); + guest_lock_component(vm); + + ret =3D __check_host_shared_guest(vm, &phys, ipa); + if (!ret) + ret =3D kvm_pgtable_stage2_relax_perms(&vm->pgt, ipa, prot, 0); + + guest_unlock_component(vm); + host_unlock_component(); + + return ret; +} --=20 2.47.1.613.gc27f4b7a9f-goog