1 /*
2  * CPU models for s390x - System Emulation-only
3  *
4  * Copyright 2016 IBM Corp.
5  *
6  * Author(s): David Hildenbrand <dahi@linux.vnet.ibm.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
9  * your option) any later version. See the COPYING file in the top-level
10  * directory.
11  */
12 
13 #include "qemu/osdep.h"
14 #include "cpu.h"
15 #include "s390x-internal.h"
16 #include "kvm/kvm_s390x.h"
17 #include "sysemu/kvm.h"
18 #include "qapi/error.h"
19 #include "qapi/visitor.h"
20 #include "qapi/qmp/qerror.h"
21 #include "qapi/qobject-input-visitor.h"
22 #include "qapi/qmp/qdict.h"
23 #include "qapi/qapi-commands-machine-target.h"
24 
25 static void list_add_feat(const char *name, void *opaque);
26 
27 static void check_unavailable_features(const S390CPUModel *max_model,
28                                        const S390CPUModel *model,
29                                        strList **unavailable)
30 {
31     S390FeatBitmap missing;
32 
33     /* check general model compatibility */
34     if (max_model->def->gen < model->def->gen ||
35         (max_model->def->gen == model->def->gen &&
36          max_model->def->ec_ga < model->def->ec_ga)) {
37         list_add_feat("type", unavailable);
38     }
39 
40     /* detect missing features if any to properly report them */
41     bitmap_andnot(missing, model->features, max_model->features,
42                   S390_FEAT_MAX);
43     if (!bitmap_empty(missing, S390_FEAT_MAX)) {
44         s390_feat_bitmap_to_ascii(missing, unavailable, list_add_feat);
45     }
46 }
47 
48 struct CpuDefinitionInfoListData {
49     CpuDefinitionInfoList *list;
50     S390CPUModel *model;
51 };
52 
53 static void create_cpu_model_list(ObjectClass *klass, void *opaque)
54 {
55     struct CpuDefinitionInfoListData *cpu_list_data = opaque;
56     CpuDefinitionInfoList **cpu_list = &cpu_list_data->list;
57     CpuDefinitionInfo *info;
58     char *name = g_strdup(object_class_get_name(klass));
59     S390CPUClass *scc = S390_CPU_CLASS(klass);
60 
61     /* strip off the -s390x-cpu */
62     g_strrstr(name, "-" TYPE_S390_CPU)[0] = 0;
63     info = g_new0(CpuDefinitionInfo, 1);
64     info->name = name;
65     info->has_migration_safe = true;
66     info->migration_safe = scc->is_migration_safe;
67     info->q_static = scc->is_static;
68     info->q_typename = g_strdup(object_class_get_name(klass));
69     /* check for unavailable features */
70     if (cpu_list_data->model) {
71         Object *obj;
72         S390CPU *sc;
73         obj = object_new_with_class(klass);
74         sc = S390_CPU(obj);
75         if (sc->model) {
76             info->has_unavailable_features = true;
77             check_unavailable_features(cpu_list_data->model, sc->model,
78                                        &info->unavailable_features);
79         }
80         object_unref(obj);
81     }
82 
83     QAPI_LIST_PREPEND(*cpu_list, info);
84 }
85 
86 CpuDefinitionInfoList *qmp_query_cpu_definitions(Error **errp)
87 {
88     struct CpuDefinitionInfoListData list_data = {
89         .list = NULL,
90     };
91 
92     list_data.model = get_max_cpu_model(NULL);
93 
94     object_class_foreach(create_cpu_model_list, TYPE_S390_CPU, false,
95                          &list_data);
96 
97     return list_data.list;
98 }
99 
100 static void cpu_model_from_info(S390CPUModel *model, const CpuModelInfo *info,
101                                 Error **errp)
102 {
103     Error *err = NULL;
104     const QDict *qdict = NULL;
105     const QDictEntry *e;
106     Visitor *visitor;
107     ObjectClass *oc;
108     S390CPU *cpu;
109     Object *obj;
110 
111     if (info->props) {
112         qdict = qobject_to(QDict, info->props);
113         if (!qdict) {
114             error_setg(errp, QERR_INVALID_PARAMETER_TYPE, "props", "dict");
115             return;
116         }
117     }
118 
119     oc = cpu_class_by_name(TYPE_S390_CPU, info->name);
120     if (!oc) {
121         error_setg(errp, "The CPU definition \'%s\' is unknown.", info->name);
122         return;
123     }
124     if (S390_CPU_CLASS(oc)->kvm_required && !kvm_enabled()) {
125         error_setg(errp, "The CPU definition '%s' requires KVM", info->name);
126         return;
127     }
128     obj = object_new_with_class(oc);
129     cpu = S390_CPU(obj);
130 
131     if (!cpu->model) {
132         error_setg(errp, "Details about the host CPU model are not available, "
133                          "it cannot be used.");
134         object_unref(obj);
135         return;
136     }
137 
138     if (qdict) {
139         visitor = qobject_input_visitor_new(info->props);
140         if (!visit_start_struct(visitor, NULL, NULL, 0, errp)) {
141             visit_free(visitor);
142             object_unref(obj);
143             return;
144         }
145         for (e = qdict_first(qdict); e; e = qdict_next(qdict, e)) {
146             if (!object_property_set(obj, e->key, visitor, &err)) {
147                 break;
148             }
149         }
150         if (!err) {
151             visit_check_struct(visitor, &err);
152         }
153         visit_end_struct(visitor, NULL);
154         visit_free(visitor);
155         if (err) {
156             error_propagate(errp, err);
157             object_unref(obj);
158             return;
159         }
160     }
161 
162     /* copy the model and throw the cpu away */
163     memcpy(model, cpu->model, sizeof(*model));
164     object_unref(obj);
165 }
166 
167 static void qdict_add_disabled_feat(const char *name, void *opaque)
168 {
169     qdict_put_bool(opaque, name, false);
170 }
171 
172 static void qdict_add_enabled_feat(const char *name, void *opaque)
173 {
174     qdict_put_bool(opaque, name, true);
175 }
176 
177 /* convert S390CPUDef into a static CpuModelInfo */
178 static void cpu_info_from_model(CpuModelInfo *info, const S390CPUModel *model,
179                                 bool delta_changes)
180 {
181     QDict *qdict = qdict_new();
182     S390FeatBitmap bitmap;
183 
184     /* always fallback to the static base model */
185     info->name = g_strdup_printf("%s-base", model->def->name);
186 
187     if (delta_changes) {
188         /* features deleted from the base feature set */
189         bitmap_andnot(bitmap, model->def->base_feat, model->features,
190                       S390_FEAT_MAX);
191         if (!bitmap_empty(bitmap, S390_FEAT_MAX)) {
192             s390_feat_bitmap_to_ascii(bitmap, qdict, qdict_add_disabled_feat);
193         }
194 
195         /* features added to the base feature set */
196         bitmap_andnot(bitmap, model->features, model->def->base_feat,
197                       S390_FEAT_MAX);
198         if (!bitmap_empty(bitmap, S390_FEAT_MAX)) {
199             s390_feat_bitmap_to_ascii(bitmap, qdict, qdict_add_enabled_feat);
200         }
201     } else {
202         /* expand all features */
203         s390_feat_bitmap_to_ascii(model->features, qdict,
204                                   qdict_add_enabled_feat);
205         bitmap_complement(bitmap, model->features, S390_FEAT_MAX);
206         s390_feat_bitmap_to_ascii(bitmap, qdict, qdict_add_disabled_feat);
207     }
208 
209     if (!qdict_size(qdict)) {
210         qobject_unref(qdict);
211     } else {
212         info->props = QOBJECT(qdict);
213     }
214 }
215 
216 CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType type,
217                                                       CpuModelInfo *model,
218                                                       Error **errp)
219 {
220     Error *err = NULL;
221     CpuModelExpansionInfo *expansion_info = NULL;
222     S390CPUModel s390_model;
223     bool delta_changes = false;
224 
225     /* convert it to our internal representation */
226     cpu_model_from_info(&s390_model, model, &err);
227     if (err) {
228         error_propagate(errp, err);
229         return NULL;
230     }
231 
232     if (type == CPU_MODEL_EXPANSION_TYPE_STATIC) {
233         delta_changes = true;
234     } else if (type != CPU_MODEL_EXPANSION_TYPE_FULL) {
235         error_setg(errp, "The requested expansion type is not supported.");
236         return NULL;
237     }
238 
239     /* convert it back to a static representation */
240     expansion_info = g_new0(CpuModelExpansionInfo, 1);
241     expansion_info->model = g_malloc0(sizeof(*expansion_info->model));
242     cpu_info_from_model(expansion_info->model, &s390_model, delta_changes);
243     return expansion_info;
244 }
245 
246 static void list_add_feat(const char *name, void *opaque)
247 {
248     strList **last = (strList **) opaque;
249 
250     QAPI_LIST_PREPEND(*last, g_strdup(name));
251 }
252 
253 CpuModelCompareInfo *qmp_query_cpu_model_comparison(CpuModelInfo *infoa,
254                                                      CpuModelInfo *infob,
255                                                      Error **errp)
256 {
257     Error *err = NULL;
258     CpuModelCompareResult feat_result, gen_result;
259     CpuModelCompareInfo *compare_info;
260     S390FeatBitmap missing, added;
261     S390CPUModel modela, modelb;
262 
263     /* convert both models to our internal representation */
264     cpu_model_from_info(&modela, infoa, &err);
265     if (err) {
266         error_propagate(errp, err);
267         return NULL;
268     }
269     cpu_model_from_info(&modelb, infob, &err);
270     if (err) {
271         error_propagate(errp, err);
272         return NULL;
273     }
274     compare_info = g_new0(CpuModelCompareInfo, 1);
275 
276     /* check the cpu generation and ga level */
277     if (modela.def->gen == modelb.def->gen) {
278         if (modela.def->ec_ga == modelb.def->ec_ga) {
279             /* ec and corresponding bc are identical */
280             gen_result = CPU_MODEL_COMPARE_RESULT_IDENTICAL;
281         } else if (modela.def->ec_ga < modelb.def->ec_ga) {
282             gen_result = CPU_MODEL_COMPARE_RESULT_SUBSET;
283         } else {
284             gen_result = CPU_MODEL_COMPARE_RESULT_SUPERSET;
285         }
286     } else if (modela.def->gen < modelb.def->gen) {
287         gen_result = CPU_MODEL_COMPARE_RESULT_SUBSET;
288     } else {
289         gen_result = CPU_MODEL_COMPARE_RESULT_SUPERSET;
290     }
291     if (gen_result != CPU_MODEL_COMPARE_RESULT_IDENTICAL) {
292         /* both models cannot be made identical */
293         list_add_feat("type", &compare_info->responsible_properties);
294     }
295 
296     /* check the feature set */
297     if (bitmap_equal(modela.features, modelb.features, S390_FEAT_MAX)) {
298         feat_result = CPU_MODEL_COMPARE_RESULT_IDENTICAL;
299     } else {
300         bitmap_andnot(missing, modela.features, modelb.features, S390_FEAT_MAX);
301         s390_feat_bitmap_to_ascii(missing,
302                                   &compare_info->responsible_properties,
303                                   list_add_feat);
304         bitmap_andnot(added, modelb.features, modela.features, S390_FEAT_MAX);
305         s390_feat_bitmap_to_ascii(added, &compare_info->responsible_properties,
306                                   list_add_feat);
307         if (bitmap_empty(missing, S390_FEAT_MAX)) {
308             feat_result = CPU_MODEL_COMPARE_RESULT_SUBSET;
309         } else if (bitmap_empty(added, S390_FEAT_MAX)) {
310             feat_result = CPU_MODEL_COMPARE_RESULT_SUPERSET;
311         } else {
312             feat_result = CPU_MODEL_COMPARE_RESULT_INCOMPATIBLE;
313         }
314     }
315 
316     /* combine the results */
317     if (gen_result == feat_result) {
318         compare_info->result = gen_result;
319     } else if (feat_result == CPU_MODEL_COMPARE_RESULT_IDENTICAL) {
320         compare_info->result = gen_result;
321     } else if (gen_result == CPU_MODEL_COMPARE_RESULT_IDENTICAL) {
322         compare_info->result = feat_result;
323     } else {
324         compare_info->result = CPU_MODEL_COMPARE_RESULT_INCOMPATIBLE;
325     }
326     return compare_info;
327 }
328 
329 CpuModelBaselineInfo *qmp_query_cpu_model_baseline(CpuModelInfo *infoa,
330                                                     CpuModelInfo *infob,
331                                                     Error **errp)
332 {
333     Error *err = NULL;
334     CpuModelBaselineInfo *baseline_info;
335     S390CPUModel modela, modelb, model;
336     uint16_t cpu_type;
337     uint8_t max_gen_ga;
338     uint8_t max_gen;
339 
340     /* convert both models to our internal representation */
341     cpu_model_from_info(&modela, infoa, &err);
342     if (err) {
343         error_propagate(errp, err);
344         return NULL;
345     }
346 
347     cpu_model_from_info(&modelb, infob, &err);
348     if (err) {
349         error_propagate(errp, err);
350         return NULL;
351     }
352 
353     /* features both models support */
354     bitmap_and(model.features, modela.features, modelb.features, S390_FEAT_MAX);
355 
356     /* detect the maximum model not regarding features */
357     if (modela.def->gen == modelb.def->gen) {
358         if (modela.def->type == modelb.def->type) {
359             cpu_type = modela.def->type;
360         } else {
361             cpu_type = 0;
362         }
363         max_gen = modela.def->gen;
364         max_gen_ga = MIN(modela.def->ec_ga, modelb.def->ec_ga);
365     } else if (modela.def->gen > modelb.def->gen) {
366         cpu_type = modelb.def->type;
367         max_gen = modelb.def->gen;
368         max_gen_ga = modelb.def->ec_ga;
369     } else {
370         cpu_type = modela.def->type;
371         max_gen = modela.def->gen;
372         max_gen_ga = modela.def->ec_ga;
373     }
374 
375     model.def = s390_find_cpu_def(cpu_type, max_gen, max_gen_ga,
376                                   model.features);
377 
378     /* models without early base features (esan3) are bad */
379     if (!model.def) {
380         error_setg(errp, "No compatible CPU model could be created as"
381                    " important base features are disabled");
382         return NULL;
383     }
384 
385     /* strip off features not part of the max model */
386     bitmap_and(model.features, model.features, model.def->full_feat,
387                S390_FEAT_MAX);
388 
389     baseline_info = g_new0(CpuModelBaselineInfo, 1);
390     baseline_info->model = g_malloc0(sizeof(*baseline_info->model));
391     cpu_info_from_model(baseline_info->model, &model, true);
392     return baseline_info;
393 }
394 
395 void apply_cpu_model(const S390CPUModel *model, Error **errp)
396 {
397     Error *err = NULL;
398     static S390CPUModel applied_model;
399     static bool applied;
400 
401     /*
402      * We have the same model for all VCPUs. KVM can only be configured before
403      * any VCPUs are defined in KVM.
404      */
405     if (applied) {
406         if (model && memcmp(&applied_model, model, sizeof(S390CPUModel))) {
407             error_setg(errp, "Mixed CPU models are not supported on s390x.");
408         }
409         return;
410     }
411 
412     if (kvm_enabled()) {
413         kvm_s390_apply_cpu_model(model, &err);
414         if (err) {
415             error_propagate(errp, err);
416             return;
417         }
418     }
419 
420     applied = true;
421     if (model) {
422         applied_model = *model;
423     }
424 }
425