David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 1 | /* |
| 2 | * TOD (Time Of Day) clock - KVM implementation |
| 3 | * |
| 4 | * Copyright 2018 Red Hat, Inc. |
| 5 | * Author(s): David Hildenbrand <david@redhat.com> |
| 6 | * |
| 7 | * This work is licensed under the terms of the GNU GPL, version 2 or later. |
| 8 | * See the COPYING file in the top-level directory. |
| 9 | */ |
| 10 | |
| 11 | #include "qemu/osdep.h" |
| 12 | #include "qapi/error.h" |
Markus Armbruster | 0b8fa32 | 2019-05-23 16:35:07 +0200 | [diff] [blame] | 13 | #include "qemu/module.h" |
Markus Armbruster | 54d3123 | 2019-08-12 07:23:59 +0200 | [diff] [blame] | 14 | #include "sysemu/runstate.h" |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 15 | #include "hw/s390x/tod.h" |
Cho, Yu-Chen | 6704360 | 2021-07-07 18:53:23 +0800 | [diff] [blame] | 16 | #include "kvm/kvm_s390x.h" |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 17 | |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 18 | static void kvm_s390_get_tod_raw(S390TOD *tod, Error **errp) |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 19 | { |
| 20 | int r; |
| 21 | |
| 22 | r = kvm_s390_get_clock_ext(&tod->high, &tod->low); |
| 23 | if (r == -ENXIO) { |
| 24 | r = kvm_s390_get_clock(&tod->high, &tod->low); |
| 25 | } |
| 26 | if (r) { |
| 27 | error_setg(errp, "Unable to get KVM guest TOD clock: %s", |
| 28 | strerror(-r)); |
| 29 | } |
| 30 | } |
| 31 | |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 32 | static void kvm_s390_tod_get(const S390TODState *td, S390TOD *tod, Error **errp) |
| 33 | { |
| 34 | if (td->stopped) { |
| 35 | *tod = td->base; |
| 36 | return; |
| 37 | } |
| 38 | |
| 39 | kvm_s390_get_tod_raw(tod, errp); |
| 40 | } |
| 41 | |
| 42 | static void kvm_s390_set_tod_raw(const S390TOD *tod, Error **errp) |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 43 | { |
| 44 | int r; |
| 45 | |
| 46 | r = kvm_s390_set_clock_ext(tod->high, tod->low); |
| 47 | if (r == -ENXIO) { |
| 48 | r = kvm_s390_set_clock(tod->high, tod->low); |
| 49 | } |
| 50 | if (r) { |
| 51 | error_setg(errp, "Unable to set KVM guest TOD clock: %s", |
| 52 | strerror(-r)); |
| 53 | } |
| 54 | } |
| 55 | |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 56 | static void kvm_s390_tod_set(S390TODState *td, const S390TOD *tod, Error **errp) |
| 57 | { |
| 58 | Error *local_err = NULL; |
| 59 | |
| 60 | /* |
| 61 | * Somebody (e.g. migration) set the TOD. We'll store it into KVM to |
| 62 | * properly detect errors now but take a look at the runstate to decide |
| 63 | * whether really to keep the tod running. E.g. during migration, this |
| 64 | * is the point where we want to stop the initially running TOD to fire |
| 65 | * it back up when actually starting the migrated guest. |
| 66 | */ |
| 67 | kvm_s390_set_tod_raw(tod, &local_err); |
| 68 | if (local_err) { |
| 69 | error_propagate(errp, local_err); |
| 70 | return; |
| 71 | } |
| 72 | |
| 73 | if (runstate_is_running()) { |
| 74 | td->stopped = false; |
| 75 | } else { |
| 76 | td->stopped = true; |
| 77 | td->base = *tod; |
| 78 | } |
| 79 | } |
| 80 | |
Philippe Mathieu-Daudé | 538f049 | 2021-01-11 16:20:20 +0100 | [diff] [blame] | 81 | static void kvm_s390_tod_vm_state_change(void *opaque, bool running, |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 82 | RunState state) |
| 83 | { |
| 84 | S390TODState *td = opaque; |
| 85 | Error *local_err = NULL; |
| 86 | |
| 87 | if (running && td->stopped) { |
| 88 | /* Set the old TOD when running the VM - start the TOD clock. */ |
| 89 | kvm_s390_set_tod_raw(&td->base, &local_err); |
| 90 | if (local_err) { |
| 91 | warn_report_err(local_err); |
| 92 | } |
| 93 | /* Treat errors like the TOD was running all the time. */ |
| 94 | td->stopped = false; |
| 95 | } else if (!running && !td->stopped) { |
| 96 | /* Store the TOD when stopping the VM - stop the TOD clock. */ |
| 97 | kvm_s390_get_tod_raw(&td->base, &local_err); |
| 98 | if (local_err) { |
| 99 | /* Keep the TOD running in case we could not back it up. */ |
| 100 | warn_report_err(local_err); |
| 101 | } else { |
| 102 | td->stopped = true; |
| 103 | } |
| 104 | } |
| 105 | } |
| 106 | |
| 107 | static void kvm_s390_tod_realize(DeviceState *dev, Error **errp) |
| 108 | { |
| 109 | S390TODState *td = S390_TOD(dev); |
| 110 | S390TODClass *tdc = S390_TOD_GET_CLASS(td); |
| 111 | Error *local_err = NULL; |
| 112 | |
| 113 | tdc->parent_realize(dev, &local_err); |
| 114 | if (local_err) { |
| 115 | error_propagate(errp, local_err); |
| 116 | return; |
| 117 | } |
| 118 | |
| 119 | /* |
| 120 | * We need to know when the VM gets started/stopped to start/stop the TOD. |
| 121 | * As we can never have more than one TOD instance (and that will never be |
| 122 | * removed), registering here and never unregistering is good enough. |
| 123 | */ |
| 124 | qemu_add_vm_change_state_handler(kvm_s390_tod_vm_state_change, td); |
| 125 | } |
| 126 | |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 127 | static void kvm_s390_tod_class_init(ObjectClass *oc, void *data) |
| 128 | { |
| 129 | S390TODClass *tdc = S390_TOD_CLASS(oc); |
| 130 | |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 131 | device_class_set_parent_realize(DEVICE_CLASS(oc), kvm_s390_tod_realize, |
| 132 | &tdc->parent_realize); |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 133 | tdc->get = kvm_s390_tod_get; |
| 134 | tdc->set = kvm_s390_tod_set; |
| 135 | } |
| 136 | |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 137 | static void kvm_s390_tod_init(Object *obj) |
| 138 | { |
| 139 | S390TODState *td = S390_TOD(obj); |
| 140 | |
| 141 | /* |
| 142 | * The TOD is initially running (value stored in KVM). Avoid needless |
| 143 | * loading/storing of the TOD when starting a simple VM, so let it |
| 144 | * run although the (never started) VM is stopped. For migration, we |
| 145 | * will properly set the TOD later. |
| 146 | */ |
| 147 | td->stopped = false; |
| 148 | } |
| 149 | |
Bernhard Beschow | 5e78c98 | 2022-01-17 15:58:04 +0100 | [diff] [blame] | 150 | static const TypeInfo kvm_s390_tod_info = { |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 151 | .name = TYPE_KVM_S390_TOD, |
| 152 | .parent = TYPE_S390_TOD, |
| 153 | .instance_size = sizeof(S390TODState), |
David Hildenbrand | 9bc9d3d | 2018-11-30 10:49:57 +0100 | [diff] [blame] | 154 | .instance_init = kvm_s390_tod_init, |
David Hildenbrand | 8046f37 | 2018-06-27 15:44:04 +0200 | [diff] [blame] | 155 | .class_init = kvm_s390_tod_class_init, |
| 156 | .class_size = sizeof(S390TODClass), |
| 157 | }; |
| 158 | |
| 159 | static void register_types(void) |
| 160 | { |
| 161 | type_register_static(&kvm_s390_tod_info); |
| 162 | } |
| 163 | type_init(register_types); |