diff options
Diffstat (limited to 'tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.c')
-rw-r--r-- | tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.c b/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.c new file mode 100644 index 0000000000..2c432fa164 --- /dev/null +++ b/tools/testing/selftests/kvm/lib/s390x/diag318_test_handler.c @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Test handler for the s390x DIAGNOSE 0x0318 instruction. + * + * Copyright (C) 2020, IBM + */ + +#include "test_util.h" +#include "kvm_util.h" + +#define ICPT_INSTRUCTION 0x04 +#define IPA0_DIAG 0x8300 + +static void guest_code(void) +{ + uint64_t diag318_info = 0x12345678; + + asm volatile ("diag %0,0,0x318\n" : : "d" (diag318_info)); +} + +/* + * The DIAGNOSE 0x0318 instruction call must be handled via userspace. As such, + * we create an ad-hoc VM here to handle the instruction then extract the + * necessary data. It is up to the caller to decide what to do with that data. + */ +static uint64_t diag318_handler(void) +{ + struct kvm_vcpu *vcpu; + struct kvm_vm *vm; + struct kvm_run *run; + uint64_t reg; + uint64_t diag318_info; + + vm = vm_create_with_one_vcpu(&vcpu, guest_code); + vcpu_run(vcpu); + run = vcpu->run; + + TEST_ASSERT_KVM_EXIT_REASON(vcpu, KVM_EXIT_S390_SIEIC); + TEST_ASSERT(run->s390_sieic.icptcode == ICPT_INSTRUCTION, + "Unexpected intercept code: 0x%x", run->s390_sieic.icptcode); + TEST_ASSERT((run->s390_sieic.ipa & 0xff00) == IPA0_DIAG, + "Unexpected IPA0 code: 0x%x", (run->s390_sieic.ipa & 0xff00)); + + reg = (run->s390_sieic.ipa & 0x00f0) >> 4; + diag318_info = run->s.regs.gprs[reg]; + + TEST_ASSERT(diag318_info != 0, "DIAGNOSE 0x0318 info not set"); + + kvm_vm_free(vm); + + return diag318_info; +} + +uint64_t get_diag318_info(void) +{ + static uint64_t diag318_info; + static bool printed_skip; + + /* + * If KVM does not support diag318, then return 0 to + * ensure tests do not break. + */ + if (!kvm_has_cap(KVM_CAP_S390_DIAG318)) { + if (!printed_skip) { + fprintf(stdout, "KVM_CAP_S390_DIAG318 not supported. " + "Skipping diag318 test.\n"); + printed_skip = true; + } + return 0; + } + + /* + * If a test has previously requested the diag318 info, + * then don't bother spinning up a temporary VM again. + */ + if (!diag318_info) + diag318_info = diag318_handler(); + + return diag318_info; +} |