Merge remote-tracking branch 'remotes/cohuck-gitlab/tags/s390x-20210121' into staging
[qemu.git] / backends / hostmem.c
1 /*
2 * QEMU Host Memory Backend
3 *
4 * Copyright (C) 2013-2014 Red Hat Inc
5 *
6 * Authors:
7 * Igor Mammedov <imammedo@redhat.com>
8 *
9 * This work is licensed under the terms of the GNU GPL, version 2 or later.
10 * See the COPYING file in the top-level directory.
11 */
12
13 #include "qemu/osdep.h"
14 #include "sysemu/hostmem.h"
15 #include "sysemu/sysemu.h"
16 #include "hw/boards.h"
17 #include "qapi/error.h"
18 #include "qapi/qapi-builtin-visit.h"
19 #include "qapi/visitor.h"
20 #include "qemu/config-file.h"
21 #include "qom/object_interfaces.h"
22 #include "qemu/mmap-alloc.h"
23
24 #ifdef CONFIG_NUMA
25 #include <numaif.h>
26 QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_DEFAULT != MPOL_DEFAULT);
27 QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_PREFERRED != MPOL_PREFERRED);
28 QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_BIND != MPOL_BIND);
29 QEMU_BUILD_BUG_ON(HOST_MEM_POLICY_INTERLEAVE != MPOL_INTERLEAVE);
30 #endif
31
32 char *
33 host_memory_backend_get_name(HostMemoryBackend *backend)
34 {
35 if (!backend->use_canonical_path) {
36 return g_strdup(object_get_canonical_path_component(OBJECT(backend)));
37 }
38
39 return object_get_canonical_path(OBJECT(backend));
40 }
41
42 static void
43 host_memory_backend_get_size(Object *obj, Visitor *v, const char *name,
44 void *opaque, Error **errp)
45 {
46 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
47 uint64_t value = backend->size;
48
49 visit_type_size(v, name, &value, errp);
50 }
51
52 static void
53 host_memory_backend_set_size(Object *obj, Visitor *v, const char *name,
54 void *opaque, Error **errp)
55 {
56 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
57 uint64_t value;
58
59 if (host_memory_backend_mr_inited(backend)) {
60 error_setg(errp, "cannot change property %s of %s ", name,
61 object_get_typename(obj));
62 return;
63 }
64
65 if (!visit_type_size(v, name, &value, errp)) {
66 return;
67 }
68 if (!value) {
69 error_setg(errp,
70 "property '%s' of %s doesn't take value '%" PRIu64 "'",
71 name, object_get_typename(obj), value);
72 return;
73 }
74 backend->size = value;
75 }
76
77 static void
78 host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name,
79 void *opaque, Error **errp)
80 {
81 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
82 uint16List *host_nodes = NULL;
83 uint16List **node = &host_nodes;
84 unsigned long value;
85
86 value = find_first_bit(backend->host_nodes, MAX_NODES);
87 if (value == MAX_NODES) {
88 goto ret;
89 }
90
91 *node = g_malloc0(sizeof(**node));
92 (*node)->value = value;
93 node = &(*node)->next;
94
95 do {
96 value = find_next_bit(backend->host_nodes, MAX_NODES, value + 1);
97 if (value == MAX_NODES) {
98 break;
99 }
100
101 *node = g_malloc0(sizeof(**node));
102 (*node)->value = value;
103 node = &(*node)->next;
104 } while (true);
105
106 ret:
107 visit_type_uint16List(v, name, &host_nodes, errp);
108 qapi_free_uint16List(host_nodes);
109 }
110
111 static void
112 host_memory_backend_set_host_nodes(Object *obj, Visitor *v, const char *name,
113 void *opaque, Error **errp)
114 {
115 #ifdef CONFIG_NUMA
116 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
117 uint16List *l, *host_nodes = NULL;
118
119 visit_type_uint16List(v, name, &host_nodes, errp);
120
121 for (l = host_nodes; l; l = l->next) {
122 if (l->value >= MAX_NODES) {
123 error_setg(errp, "Invalid host-nodes value: %d", l->value);
124 goto out;
125 }
126 }
127
128 for (l = host_nodes; l; l = l->next) {
129 bitmap_set(backend->host_nodes, l->value, 1);
130 }
131
132 out:
133 qapi_free_uint16List(host_nodes);
134 #else
135 error_setg(errp, "NUMA node binding are not supported by this QEMU");
136 #endif
137 }
138
139 static int
140 host_memory_backend_get_policy(Object *obj, Error **errp G_GNUC_UNUSED)
141 {
142 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
143 return backend->policy;
144 }
145
146 static void
147 host_memory_backend_set_policy(Object *obj, int policy, Error **errp)
148 {
149 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
150 backend->policy = policy;
151
152 #ifndef CONFIG_NUMA
153 if (policy != HOST_MEM_POLICY_DEFAULT) {
154 error_setg(errp, "NUMA policies are not supported by this QEMU");
155 }
156 #endif
157 }
158
159 static bool host_memory_backend_get_merge(Object *obj, Error **errp)
160 {
161 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
162
163 return backend->merge;
164 }
165
166 static void host_memory_backend_set_merge(Object *obj, bool value, Error **errp)
167 {
168 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
169
170 if (!host_memory_backend_mr_inited(backend)) {
171 backend->merge = value;
172 return;
173 }
174
175 if (value != backend->merge) {
176 void *ptr = memory_region_get_ram_ptr(&backend->mr);
177 uint64_t sz = memory_region_size(&backend->mr);
178
179 qemu_madvise(ptr, sz,
180 value ? QEMU_MADV_MERGEABLE : QEMU_MADV_UNMERGEABLE);
181 backend->merge = value;
182 }
183 }
184
185 static bool host_memory_backend_get_dump(Object *obj, Error **errp)
186 {
187 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
188
189 return backend->dump;
190 }
191
192 static void host_memory_backend_set_dump(Object *obj, bool value, Error **errp)
193 {
194 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
195
196 if (!host_memory_backend_mr_inited(backend)) {
197 backend->dump = value;
198 return;
199 }
200
201 if (value != backend->dump) {
202 void *ptr = memory_region_get_ram_ptr(&backend->mr);
203 uint64_t sz = memory_region_size(&backend->mr);
204
205 qemu_madvise(ptr, sz,
206 value ? QEMU_MADV_DODUMP : QEMU_MADV_DONTDUMP);
207 backend->dump = value;
208 }
209 }
210
211 static bool host_memory_backend_get_prealloc(Object *obj, Error **errp)
212 {
213 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
214
215 return backend->prealloc;
216 }
217
218 static void host_memory_backend_set_prealloc(Object *obj, bool value,
219 Error **errp)
220 {
221 Error *local_err = NULL;
222 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
223
224 if (!host_memory_backend_mr_inited(backend)) {
225 backend->prealloc = value;
226 return;
227 }
228
229 if (value && !backend->prealloc) {
230 int fd = memory_region_get_fd(&backend->mr);
231 void *ptr = memory_region_get_ram_ptr(&backend->mr);
232 uint64_t sz = memory_region_size(&backend->mr);
233
234 os_mem_prealloc(fd, ptr, sz, backend->prealloc_threads, &local_err);
235 if (local_err) {
236 error_propagate(errp, local_err);
237 return;
238 }
239 backend->prealloc = true;
240 }
241 }
242
243 static void host_memory_backend_get_prealloc_threads(Object *obj, Visitor *v,
244 const char *name, void *opaque, Error **errp)
245 {
246 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
247 visit_type_uint32(v, name, &backend->prealloc_threads, errp);
248 }
249
250 static void host_memory_backend_set_prealloc_threads(Object *obj, Visitor *v,
251 const char *name, void *opaque, Error **errp)
252 {
253 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
254 uint32_t value;
255
256 if (!visit_type_uint32(v, name, &value, errp)) {
257 return;
258 }
259 if (value <= 0) {
260 error_setg(errp, "property '%s' of %s doesn't take value '%d'", name,
261 object_get_typename(obj), value);
262 return;
263 }
264 backend->prealloc_threads = value;
265 }
266
267 static void host_memory_backend_init(Object *obj)
268 {
269 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
270 MachineState *machine = MACHINE(qdev_get_machine());
271
272 /* TODO: convert access to globals to compat properties */
273 backend->merge = machine_mem_merge(machine);
274 backend->dump = machine_dump_guest_core(machine);
275 backend->prealloc_threads = 1;
276 }
277
278 static void host_memory_backend_post_init(Object *obj)
279 {
280 object_apply_compat_props(obj);
281 }
282
283 bool host_memory_backend_mr_inited(HostMemoryBackend *backend)
284 {
285 /*
286 * NOTE: We forbid zero-length memory backend, so here zero means
287 * "we haven't inited the backend memory region yet".
288 */
289 return memory_region_size(&backend->mr) != 0;
290 }
291
292 MemoryRegion *host_memory_backend_get_memory(HostMemoryBackend *backend)
293 {
294 return host_memory_backend_mr_inited(backend) ? &backend->mr : NULL;
295 }
296
297 void host_memory_backend_set_mapped(HostMemoryBackend *backend, bool mapped)
298 {
299 backend->is_mapped = mapped;
300 }
301
302 bool host_memory_backend_is_mapped(HostMemoryBackend *backend)
303 {
304 return backend->is_mapped;
305 }
306
307 #ifdef __linux__
308 size_t host_memory_backend_pagesize(HostMemoryBackend *memdev)
309 {
310 Object *obj = OBJECT(memdev);
311 char *path = object_property_get_str(obj, "mem-path", NULL);
312 size_t pagesize = qemu_mempath_getpagesize(path);
313
314 g_free(path);
315 return pagesize;
316 }
317 #else
318 size_t host_memory_backend_pagesize(HostMemoryBackend *memdev)
319 {
320 return qemu_real_host_page_size;
321 }
322 #endif
323
324 static void
325 host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
326 {
327 HostMemoryBackend *backend = MEMORY_BACKEND(uc);
328 HostMemoryBackendClass *bc = MEMORY_BACKEND_GET_CLASS(uc);
329 Error *local_err = NULL;
330 void *ptr;
331 uint64_t sz;
332
333 if (bc->alloc) {
334 bc->alloc(backend, &local_err);
335 if (local_err) {
336 goto out;
337 }
338
339 ptr = memory_region_get_ram_ptr(&backend->mr);
340 sz = memory_region_size(&backend->mr);
341
342 if (backend->merge) {
343 qemu_madvise(ptr, sz, QEMU_MADV_MERGEABLE);
344 }
345 if (!backend->dump) {
346 qemu_madvise(ptr, sz, QEMU_MADV_DONTDUMP);
347 }
348 #ifdef CONFIG_NUMA
349 unsigned long lastbit = find_last_bit(backend->host_nodes, MAX_NODES);
350 /* lastbit == MAX_NODES means maxnode = 0 */
351 unsigned long maxnode = (lastbit + 1) % (MAX_NODES + 1);
352 /* ensure policy won't be ignored in case memory is preallocated
353 * before mbind(). note: MPOL_MF_STRICT is ignored on hugepages so
354 * this doesn't catch hugepage case. */
355 unsigned flags = MPOL_MF_STRICT | MPOL_MF_MOVE;
356
357 /* check for invalid host-nodes and policies and give more verbose
358 * error messages than mbind(). */
359 if (maxnode && backend->policy == MPOL_DEFAULT) {
360 error_setg(errp, "host-nodes must be empty for policy default,"
361 " or you should explicitly specify a policy other"
362 " than default");
363 return;
364 } else if (maxnode == 0 && backend->policy != MPOL_DEFAULT) {
365 error_setg(errp, "host-nodes must be set for policy %s",
366 HostMemPolicy_str(backend->policy));
367 return;
368 }
369
370 /* We can have up to MAX_NODES nodes, but we need to pass maxnode+1
371 * as argument to mbind() due to an old Linux bug (feature?) which
372 * cuts off the last specified node. This means backend->host_nodes
373 * must have MAX_NODES+1 bits available.
374 */
375 assert(sizeof(backend->host_nodes) >=
376 BITS_TO_LONGS(MAX_NODES + 1) * sizeof(unsigned long));
377 assert(maxnode <= MAX_NODES);
378
379 if (maxnode &&
380 mbind(ptr, sz, backend->policy, backend->host_nodes, maxnode + 1,
381 flags)) {
382 if (backend->policy != MPOL_DEFAULT || errno != ENOSYS) {
383 error_setg_errno(errp, errno,
384 "cannot bind memory to host NUMA nodes");
385 return;
386 }
387 }
388 #endif
389 /* Preallocate memory after the NUMA policy has been instantiated.
390 * This is necessary to guarantee memory is allocated with
391 * specified NUMA policy in place.
392 */
393 if (backend->prealloc) {
394 os_mem_prealloc(memory_region_get_fd(&backend->mr), ptr, sz,
395 backend->prealloc_threads, &local_err);
396 if (local_err) {
397 goto out;
398 }
399 }
400 }
401 out:
402 error_propagate(errp, local_err);
403 }
404
405 static bool
406 host_memory_backend_can_be_deleted(UserCreatable *uc)
407 {
408 if (host_memory_backend_is_mapped(MEMORY_BACKEND(uc))) {
409 return false;
410 } else {
411 return true;
412 }
413 }
414
415 static bool host_memory_backend_get_share(Object *o, Error **errp)
416 {
417 HostMemoryBackend *backend = MEMORY_BACKEND(o);
418
419 return backend->share;
420 }
421
422 static void host_memory_backend_set_share(Object *o, bool value, Error **errp)
423 {
424 HostMemoryBackend *backend = MEMORY_BACKEND(o);
425
426 if (host_memory_backend_mr_inited(backend)) {
427 error_setg(errp, "cannot change property value");
428 return;
429 }
430 backend->share = value;
431 }
432
433 static bool
434 host_memory_backend_get_use_canonical_path(Object *obj, Error **errp)
435 {
436 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
437
438 return backend->use_canonical_path;
439 }
440
441 static void
442 host_memory_backend_set_use_canonical_path(Object *obj, bool value,
443 Error **errp)
444 {
445 HostMemoryBackend *backend = MEMORY_BACKEND(obj);
446
447 backend->use_canonical_path = value;
448 }
449
450 static void
451 host_memory_backend_class_init(ObjectClass *oc, void *data)
452 {
453 UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
454
455 ucc->complete = host_memory_backend_memory_complete;
456 ucc->can_be_deleted = host_memory_backend_can_be_deleted;
457
458 object_class_property_add_bool(oc, "merge",
459 host_memory_backend_get_merge,
460 host_memory_backend_set_merge);
461 object_class_property_set_description(oc, "merge",
462 "Mark memory as mergeable");
463 object_class_property_add_bool(oc, "dump",
464 host_memory_backend_get_dump,
465 host_memory_backend_set_dump);
466 object_class_property_set_description(oc, "dump",
467 "Set to 'off' to exclude from core dump");
468 object_class_property_add_bool(oc, "prealloc",
469 host_memory_backend_get_prealloc,
470 host_memory_backend_set_prealloc);
471 object_class_property_set_description(oc, "prealloc",
472 "Preallocate memory");
473 object_class_property_add(oc, "prealloc-threads", "int",
474 host_memory_backend_get_prealloc_threads,
475 host_memory_backend_set_prealloc_threads,
476 NULL, NULL);
477 object_class_property_set_description(oc, "prealloc-threads",
478 "Number of CPU threads to use for prealloc");
479 object_class_property_add(oc, "size", "int",
480 host_memory_backend_get_size,
481 host_memory_backend_set_size,
482 NULL, NULL);
483 object_class_property_set_description(oc, "size",
484 "Size of the memory region (ex: 500M)");
485 object_class_property_add(oc, "host-nodes", "int",
486 host_memory_backend_get_host_nodes,
487 host_memory_backend_set_host_nodes,
488 NULL, NULL);
489 object_class_property_set_description(oc, "host-nodes",
490 "Binds memory to the list of NUMA host nodes");
491 object_class_property_add_enum(oc, "policy", "HostMemPolicy",
492 &HostMemPolicy_lookup,
493 host_memory_backend_get_policy,
494 host_memory_backend_set_policy);
495 object_class_property_set_description(oc, "policy",
496 "Set the NUMA policy");
497 object_class_property_add_bool(oc, "share",
498 host_memory_backend_get_share, host_memory_backend_set_share);
499 object_class_property_set_description(oc, "share",
500 "Mark the memory as private to QEMU or shared");
501 object_class_property_add_bool(oc, "x-use-canonical-path-for-ramblock-id",
502 host_memory_backend_get_use_canonical_path,
503 host_memory_backend_set_use_canonical_path);
504 }
505
506 static const TypeInfo host_memory_backend_info = {
507 .name = TYPE_MEMORY_BACKEND,
508 .parent = TYPE_OBJECT,
509 .abstract = true,
510 .class_size = sizeof(HostMemoryBackendClass),
511 .class_init = host_memory_backend_class_init,
512 .instance_size = sizeof(HostMemoryBackend),
513 .instance_init = host_memory_backend_init,
514 .instance_post_init = host_memory_backend_post_init,
515 .interfaces = (InterfaceInfo[]) {
516 { TYPE_USER_CREATABLE },
517 { }
518 }
519 };
520
521 static void register_types(void)
522 {
523 type_register_static(&host_memory_backend_info);
524 }
525
526 type_init(register_types);