From: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> Use the access key operand to check for key protection when translating guest addresses. Since the translation code checks for accessing exceptions/error hvas, we can remove the check here and simplify the control flow. Keep checking if the memory is read-only even if such memslots are currently not supported. handle_tprot was the last user of guest_translate_address, so remove it. Signed-off-by: Janis Schoetterl-Glausch <scgl@xxxxxxxxxxxxx> Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx> Reviewed-by: Claudio Imbrenda <imbrenda@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20220211182215.2730017-4-scgl@xxxxxxxxxxxxx Signed-off-by: Christian Borntraeger <borntraeger@xxxxxxxxxxxxx> --- arch/s390/kvm/gaccess.c | 9 ------ arch/s390/kvm/gaccess.h | 3 -- arch/s390/kvm/priv.c | 66 ++++++++++++++++++++++------------------- 3 files changed, 35 insertions(+), 43 deletions(-) diff --git a/arch/s390/kvm/gaccess.c b/arch/s390/kvm/gaccess.c index 7fca0cff4c12..37838f637707 100644 --- a/arch/s390/kvm/gaccess.c +++ b/arch/s390/kvm/gaccess.c @@ -1118,15 +1118,6 @@ int guest_translate_address_with_key(struct kvm_vcpu *vcpu, unsigned long gva, u access_key); } -int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar, - unsigned long *gpa, enum gacc_mode mode) -{ - u8 access_key = psw_bits(vcpu->arch.sie_block->gpsw).key; - - return guest_translate_address_with_key(vcpu, gva, ar, gpa, mode, - access_key); -} - /** * check_gva_range - test a range of guest virtual addresses for accessibility * @vcpu: virtual cpu diff --git a/arch/s390/kvm/gaccess.h b/arch/s390/kvm/gaccess.h index e5b2f56e7962..c5f2e7311b17 100644 --- a/arch/s390/kvm/gaccess.h +++ b/arch/s390/kvm/gaccess.h @@ -190,9 +190,6 @@ int guest_translate_address_with_key(struct kvm_vcpu *vcpu, unsigned long gva, u unsigned long *gpa, enum gacc_mode mode, u8 access_key); -int guest_translate_address(struct kvm_vcpu *vcpu, unsigned long gva, - u8 ar, unsigned long *gpa, enum gacc_mode mode); - int check_gva_range(struct kvm_vcpu *vcpu, unsigned long gva, u8 ar, unsigned long length, enum gacc_mode mode, u8 access_key); diff --git a/arch/s390/kvm/priv.c b/arch/s390/kvm/priv.c index 417154b314a6..30b24c42ef99 100644 --- a/arch/s390/kvm/priv.c +++ b/arch/s390/kvm/priv.c @@ -1443,10 +1443,11 @@ int kvm_s390_handle_eb(struct kvm_vcpu *vcpu) static int handle_tprot(struct kvm_vcpu *vcpu) { - u64 address1, address2; - unsigned long hva, gpa; - int ret = 0, cc = 0; + u64 address, operand2; + unsigned long gpa; + u8 access_key; bool writable; + int ret, cc; u8 ar; vcpu->stat.instruction_tprot++; @@ -1454,43 +1455,46 @@ static int handle_tprot(struct kvm_vcpu *vcpu) if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_PSTATE) return kvm_s390_inject_program_int(vcpu, PGM_PRIVILEGED_OP); - kvm_s390_get_base_disp_sse(vcpu, &address1, &address2, &ar, NULL); + kvm_s390_get_base_disp_sse(vcpu, &address, &operand2, &ar, NULL); + access_key = (operand2 & 0xf0) >> 4; - /* we only handle the Linux memory detection case: - * access key == 0 - * everything else goes to userspace. */ - if (address2 & 0xf0) - return -EOPNOTSUPP; if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT) ipte_lock(vcpu); - ret = guest_translate_address(vcpu, address1, ar, &gpa, GACC_STORE); - if (ret == PGM_PROTECTION) { + + ret = guest_translate_address_with_key(vcpu, address, ar, &gpa, + GACC_STORE, access_key); + if (ret == 0) { + gfn_to_hva_prot(vcpu->kvm, gpa_to_gfn(gpa), &writable); + } else if (ret == PGM_PROTECTION) { + writable = false; /* Write protected? Try again with read-only... */ - cc = 1; - ret = guest_translate_address(vcpu, address1, ar, &gpa, - GACC_FETCH); + ret = guest_translate_address_with_key(vcpu, address, ar, &gpa, + GACC_FETCH, access_key); } - if (ret) { - if (ret == PGM_ADDRESSING || ret == PGM_TRANSLATION_SPEC) { - ret = kvm_s390_inject_program_int(vcpu, ret); - } else if (ret > 0) { - /* Translation not available */ - kvm_s390_set_psw_cc(vcpu, 3); + if (ret >= 0) { + cc = -1; + + /* Fetching permitted; storing permitted */ + if (ret == 0 && writable) + cc = 0; + /* Fetching permitted; storing not permitted */ + else if (ret == 0 && !writable) + cc = 1; + /* Fetching not permitted; storing not permitted */ + else if (ret == PGM_PROTECTION) + cc = 2; + /* Translation not available */ + else if (ret != PGM_ADDRESSING && ret != PGM_TRANSLATION_SPEC) + cc = 3; + + if (cc != -1) { + kvm_s390_set_psw_cc(vcpu, cc); ret = 0; + } else { + ret = kvm_s390_inject_program_int(vcpu, ret); } - goto out_unlock; } - hva = gfn_to_hva_prot(vcpu->kvm, gpa_to_gfn(gpa), &writable); - if (kvm_is_error_hva(hva)) { - ret = kvm_s390_inject_program_int(vcpu, PGM_ADDRESSING); - } else { - if (!writable) - cc = 1; /* Write not permitted ==> read-only */ - kvm_s390_set_psw_cc(vcpu, cc); - /* Note: CC2 only occurs for storage keys (not supported yet) */ - } -out_unlock: if (vcpu->arch.sie_block->gpsw.mask & PSW_MASK_DAT) ipte_unlock(vcpu); return ret; -- 2.35.1
