xref: /qemu/hw/s390x/s390-stattrib.c (revision 5ac034b1)
1 /*
2  * s390 storage attributes device
3  *
4  * Copyright 2016 IBM Corp.
5  * Author(s): Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
6  *
7  * This work is licensed under the terms of the GNU GPL, version 2 or (at
8  * your option) any later version. See the COPYING file in the top-level
9  * directory.
10  */
11 
12 #include "qemu/osdep.h"
13 #include "qemu/units.h"
14 #include "migration/qemu-file.h"
15 #include "migration/register.h"
16 #include "hw/s390x/storage-attributes.h"
17 #include "qemu/error-report.h"
18 #include "exec/ram_addr.h"
19 #include "qapi/error.h"
20 #include "qapi/qmp/qdict.h"
21 
22 /* 512KiB cover 2GB of guest memory */
23 #define CMMA_BLOCK_SIZE  (512 * KiB)
24 
25 #define STATTR_FLAG_EOS     0x01ULL
26 #define STATTR_FLAG_MORE    0x02ULL
27 #define STATTR_FLAG_ERROR   0x04ULL
28 #define STATTR_FLAG_DONE    0x08ULL
29 
30 static S390StAttribState *s390_get_stattrib_device(void)
31 {
32     S390StAttribState *sas;
33 
34     sas = S390_STATTRIB(object_resolve_path_type("", TYPE_S390_STATTRIB, NULL));
35     assert(sas);
36     return sas;
37 }
38 
39 void s390_stattrib_init(void)
40 {
41     Object *obj;
42 
43     obj = kvm_s390_stattrib_create();
44     if (!obj) {
45         obj = object_new(TYPE_QEMU_S390_STATTRIB);
46     }
47 
48     object_property_add_child(qdev_get_machine(), TYPE_S390_STATTRIB,
49                               obj);
50     object_unref(obj);
51 
52     qdev_realize(DEVICE(obj), NULL, &error_fatal);
53 }
54 
55 /* Console commands: */
56 
57 void hmp_migrationmode(Monitor *mon, const QDict *qdict)
58 {
59     S390StAttribState *sas = s390_get_stattrib_device();
60     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
61     uint64_t what = qdict_get_int(qdict, "mode");
62     int r;
63 
64     r = sac->set_migrationmode(sas, what);
65     if (r < 0) {
66         monitor_printf(mon, "Error: %s", strerror(-r));
67     }
68 }
69 
70 void hmp_info_cmma(Monitor *mon, const QDict *qdict)
71 {
72     S390StAttribState *sas = s390_get_stattrib_device();
73     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
74     uint64_t addr = qdict_get_int(qdict, "addr");
75     uint64_t buflen = qdict_get_try_int(qdict, "count", 8);
76     uint8_t *vals;
77     int cx, len;
78 
79     vals = g_try_malloc(buflen);
80     if (!vals) {
81         monitor_printf(mon, "Error: %s\n", strerror(errno));
82         return;
83     }
84 
85     len = sac->peek_stattr(sas, addr / TARGET_PAGE_SIZE, buflen, vals);
86     if (len < 0) {
87         monitor_printf(mon, "Error: %s", strerror(-len));
88         goto out;
89     }
90 
91     monitor_printf(mon, "  CMMA attributes, "
92                    "pages %" PRIu64 "+%d (0x%" PRIx64 "):\n",
93                    addr / TARGET_PAGE_SIZE, len, addr & ~TARGET_PAGE_MASK);
94     for (cx = 0; cx < len; cx++) {
95         if (cx % 8 == 7) {
96             monitor_printf(mon, "%02x\n", vals[cx]);
97         } else {
98             monitor_printf(mon, "%02x", vals[cx]);
99         }
100     }
101     monitor_printf(mon, "\n");
102 
103 out:
104     g_free(vals);
105 }
106 
107 /* Migration support: */
108 
109 static int cmma_load(QEMUFile *f, void *opaque, int version_id)
110 {
111     S390StAttribState *sas = S390_STATTRIB(opaque);
112     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
113     uint64_t count, cur_gfn;
114     int flags, ret = 0;
115     ram_addr_t addr;
116     uint8_t *buf;
117 
118     while (!ret) {
119         addr = qemu_get_be64(f);
120         flags = addr & ~TARGET_PAGE_MASK;
121         addr &= TARGET_PAGE_MASK;
122 
123         switch (flags) {
124         case STATTR_FLAG_MORE: {
125             cur_gfn = addr / TARGET_PAGE_SIZE;
126             count = qemu_get_be64(f);
127             buf = g_try_malloc(count);
128             if (!buf) {
129                 error_report("cmma_load could not allocate memory");
130                 ret = -ENOMEM;
131                 break;
132             }
133 
134             qemu_get_buffer(f, buf, count);
135             ret = sac->set_stattr(sas, cur_gfn, count, buf);
136             if (ret < 0) {
137                 error_report("Error %d while setting storage attributes", ret);
138             }
139             g_free(buf);
140             break;
141         }
142         case STATTR_FLAG_ERROR: {
143             error_report("Storage attributes data is incomplete");
144             ret = -EINVAL;
145             break;
146         }
147         case STATTR_FLAG_DONE:
148             /* This is after the last pre-copied value has been sent, nothing
149              * more will be sent after this. Pre-copy has finished, and we
150              * are done flushing all the remaining values. Now the target
151              * system is about to take over. We synchronize the buffer to
152              * apply the actual correct values where needed.
153              */
154              sac->synchronize(sas);
155             break;
156         case STATTR_FLAG_EOS:
157             /* Normal exit */
158             return 0;
159         default:
160             error_report("Unexpected storage attribute flag data: %#x", flags);
161             ret = -EINVAL;
162         }
163     }
164 
165     return ret;
166 }
167 
168 static int cmma_save_setup(QEMUFile *f, void *opaque)
169 {
170     S390StAttribState *sas = S390_STATTRIB(opaque);
171     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
172     int res;
173     /*
174      * Signal that we want to start a migration, thus needing PGSTE dirty
175      * tracking.
176      */
177     res = sac->set_migrationmode(sas, 1);
178     if (res) {
179         return res;
180     }
181     qemu_put_be64(f, STATTR_FLAG_EOS);
182     return 0;
183 }
184 
185 static void cmma_state_pending(void *opaque, uint64_t *must_precopy,
186                                uint64_t *can_postcopy)
187 {
188     S390StAttribState *sas = S390_STATTRIB(opaque);
189     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
190     long long res = sac->get_dirtycount(sas);
191 
192     if (res >= 0) {
193         *must_precopy += res;
194     }
195 }
196 
197 static int cmma_save(QEMUFile *f, void *opaque, int final)
198 {
199     S390StAttribState *sas = S390_STATTRIB(opaque);
200     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
201     uint8_t *buf;
202     int r, cx, reallen = 0, ret = 0;
203     uint32_t buflen = CMMA_BLOCK_SIZE;
204     uint64_t start_gfn = sas->migration_cur_gfn;
205 
206     buf = g_try_malloc(buflen);
207     if (!buf) {
208         error_report("Could not allocate memory to save storage attributes");
209         return -ENOMEM;
210     }
211 
212     while (final ? 1 : qemu_file_rate_limit(f) == 0) {
213         reallen = sac->get_stattr(sas, &start_gfn, buflen, buf);
214         if (reallen < 0) {
215             g_free(buf);
216             return reallen;
217         }
218 
219         ret = 1;
220         if (!reallen) {
221             break;
222         }
223         qemu_put_be64(f, (start_gfn << TARGET_PAGE_BITS) | STATTR_FLAG_MORE);
224         qemu_put_be64(f, reallen);
225         for (cx = 0; cx < reallen; cx++) {
226             qemu_put_byte(f, buf[cx]);
227         }
228         if (!sac->get_dirtycount(sas)) {
229             break;
230         }
231     }
232 
233     sas->migration_cur_gfn = start_gfn + reallen;
234     g_free(buf);
235     if (final) {
236         qemu_put_be64(f, STATTR_FLAG_DONE);
237     }
238     qemu_put_be64(f, STATTR_FLAG_EOS);
239 
240     r = qemu_file_get_error(f);
241     if (r < 0) {
242         return r;
243     }
244 
245     return ret;
246 }
247 
248 static int cmma_save_iterate(QEMUFile *f, void *opaque)
249 {
250     return cmma_save(f, opaque, 0);
251 }
252 
253 static int cmma_save_complete(QEMUFile *f, void *opaque)
254 {
255     return cmma_save(f, opaque, 1);
256 }
257 
258 static void cmma_save_cleanup(void *opaque)
259 {
260     S390StAttribState *sas = S390_STATTRIB(opaque);
261     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
262     sac->set_migrationmode(sas, 0);
263 }
264 
265 static bool cmma_active(void *opaque)
266 {
267     S390StAttribState *sas = S390_STATTRIB(opaque);
268     S390StAttribClass *sac = S390_STATTRIB_GET_CLASS(sas);
269     return sac->get_active(sas);
270 }
271 
272 /* QEMU object: */
273 
274 static void qemu_s390_stattrib_instance_init(Object *obj)
275 {
276 }
277 
278 static int qemu_s390_peek_stattr_stub(S390StAttribState *sa, uint64_t start_gfn,
279                                      uint32_t count, uint8_t *values)
280 {
281     return 0;
282 }
283 static void qemu_s390_synchronize_stub(S390StAttribState *sa)
284 {
285 }
286 static int qemu_s390_get_stattr_stub(S390StAttribState *sa, uint64_t *start_gfn,
287                                      uint32_t count, uint8_t *values)
288 {
289     return 0;
290 }
291 static long long qemu_s390_get_dirtycount_stub(S390StAttribState *sa)
292 {
293     return 0;
294 }
295 static int qemu_s390_set_migrationmode_stub(S390StAttribState *sa, bool value)
296 {
297     return 0;
298 }
299 
300 static int qemu_s390_get_active(S390StAttribState *sa)
301 {
302     return sa->migration_enabled;
303 }
304 
305 static void qemu_s390_stattrib_class_init(ObjectClass *oc, void *data)
306 {
307     S390StAttribClass *sa_cl = S390_STATTRIB_CLASS(oc);
308     DeviceClass *dc = DEVICE_CLASS(oc);
309 
310     sa_cl->synchronize = qemu_s390_synchronize_stub;
311     sa_cl->get_stattr = qemu_s390_get_stattr_stub;
312     sa_cl->set_stattr = qemu_s390_peek_stattr_stub;
313     sa_cl->peek_stattr = qemu_s390_peek_stattr_stub;
314     sa_cl->set_migrationmode = qemu_s390_set_migrationmode_stub;
315     sa_cl->get_dirtycount = qemu_s390_get_dirtycount_stub;
316     sa_cl->get_active = qemu_s390_get_active;
317 
318     /* Reason: Can only be instantiated one time (internally) */
319     dc->user_creatable = false;
320 }
321 
322 static const TypeInfo qemu_s390_stattrib_info = {
323     .name          = TYPE_QEMU_S390_STATTRIB,
324     .parent        = TYPE_S390_STATTRIB,
325     .instance_init = qemu_s390_stattrib_instance_init,
326     .instance_size = sizeof(QEMUS390StAttribState),
327     .class_init    = qemu_s390_stattrib_class_init,
328     .class_size    = sizeof(S390StAttribClass),
329 };
330 
331 /* Generic abstract object: */
332 
333 static void s390_stattrib_realize(DeviceState *dev, Error **errp)
334 {
335     bool ambiguous = false;
336 
337     object_resolve_path_type("", TYPE_S390_STATTRIB, &ambiguous);
338     if (ambiguous) {
339         error_setg(errp, "storage_attributes device already exists");
340     }
341 }
342 
343 static void s390_stattrib_class_init(ObjectClass *oc, void *data)
344 {
345     DeviceClass *dc = DEVICE_CLASS(oc);
346 
347     dc->hotpluggable = false;
348     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
349     dc->realize = s390_stattrib_realize;
350 }
351 
352 static inline bool s390_stattrib_get_migration_enabled(Object *obj,
353                                                        Error **errp)
354 {
355     S390StAttribState *s = S390_STATTRIB(obj);
356 
357     return s->migration_enabled;
358 }
359 
360 static inline void s390_stattrib_set_migration_enabled(Object *obj, bool value,
361                                             Error **errp)
362 {
363     S390StAttribState *s = S390_STATTRIB(obj);
364 
365     s->migration_enabled = value;
366 }
367 
368 static SaveVMHandlers savevm_s390_stattrib_handlers = {
369     .save_setup = cmma_save_setup,
370     .save_live_iterate = cmma_save_iterate,
371     .save_live_complete_precopy = cmma_save_complete,
372     .state_pending_exact = cmma_state_pending,
373     .state_pending_estimate = cmma_state_pending,
374     .save_cleanup = cmma_save_cleanup,
375     .load_state = cmma_load,
376     .is_active = cmma_active,
377 };
378 
379 static void s390_stattrib_instance_init(Object *obj)
380 {
381     S390StAttribState *sas = S390_STATTRIB(obj);
382 
383     register_savevm_live(TYPE_S390_STATTRIB, 0, 0,
384                          &savevm_s390_stattrib_handlers, sas);
385 
386     object_property_add_bool(obj, "migration-enabled",
387                              s390_stattrib_get_migration_enabled,
388                              s390_stattrib_set_migration_enabled);
389     object_property_set_bool(obj, "migration-enabled", true, NULL);
390     sas->migration_cur_gfn = 0;
391 }
392 
393 static const TypeInfo s390_stattrib_info = {
394     .name          = TYPE_S390_STATTRIB,
395     .parent        = TYPE_DEVICE,
396     .instance_init = s390_stattrib_instance_init,
397     .instance_size = sizeof(S390StAttribState),
398     .class_init    = s390_stattrib_class_init,
399     .class_size    = sizeof(S390StAttribClass),
400     .abstract      = true,
401 };
402 
403 static void s390_stattrib_register_types(void)
404 {
405     type_register_static(&s390_stattrib_info);
406     type_register_static(&qemu_s390_stattrib_info);
407 }
408 
409 type_init(s390_stattrib_register_types)
410