xref: /openbmc/linux/drivers/xen/sys-hypervisor.c (revision 47010c04)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  copyright (c) 2006 IBM Corporation
4  *  Authored by: Mike D. Day <ncmike@us.ibm.com>
5  */
6 
7 #include <linux/slab.h>
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/kobject.h>
11 #include <linux/err.h>
12 
13 #include <asm/xen/hypervisor.h>
14 #include <asm/xen/hypercall.h>
15 
16 #include <xen/xen.h>
17 #include <xen/xenbus.h>
18 #include <xen/interface/xen.h>
19 #include <xen/interface/version.h>
20 #ifdef CONFIG_XEN_HAVE_VPMU
21 #include <xen/interface/xenpmu.h>
22 #endif
23 
24 #define HYPERVISOR_ATTR_RO(_name) \
25 static struct hyp_sysfs_attr _name##_attr = __ATTR_RO(_name)
26 
27 #define HYPERVISOR_ATTR_RW(_name) \
28 static struct hyp_sysfs_attr _name##_attr = __ATTR_RW(_name)
29 
30 struct hyp_sysfs_attr {
31 	struct attribute attr;
32 	ssize_t (*show)(struct hyp_sysfs_attr *, char *);
33 	ssize_t (*store)(struct hyp_sysfs_attr *, const char *, size_t);
34 	void *hyp_attr_data;
35 };
36 
37 static ssize_t type_show(struct hyp_sysfs_attr *attr, char *buffer)
38 {
39 	return sprintf(buffer, "xen\n");
40 }
41 
42 HYPERVISOR_ATTR_RO(type);
43 
44 static int __init xen_sysfs_type_init(void)
45 {
46 	return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
47 }
48 
49 static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
50 {
51 	const char *type;
52 
53 	switch (xen_domain_type) {
54 	case XEN_NATIVE:
55 		/* ARM only. */
56 		type = "Xen";
57 		break;
58 	case XEN_PV_DOMAIN:
59 		type = "PV";
60 		break;
61 	case XEN_HVM_DOMAIN:
62 		type = xen_pvh_domain() ? "PVH" : "HVM";
63 		break;
64 	default:
65 		return -EINVAL;
66 	}
67 
68 	return sprintf(buffer, "%s\n", type);
69 }
70 
71 HYPERVISOR_ATTR_RO(guest_type);
72 
73 static int __init xen_sysfs_guest_type_init(void)
74 {
75 	return sysfs_create_file(hypervisor_kobj, &guest_type_attr.attr);
76 }
77 
78 /* xen version attributes */
79 static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
80 {
81 	int version = HYPERVISOR_xen_version(XENVER_version, NULL);
82 	if (version)
83 		return sprintf(buffer, "%d\n", version >> 16);
84 	return -ENODEV;
85 }
86 
87 HYPERVISOR_ATTR_RO(major);
88 
89 static ssize_t minor_show(struct hyp_sysfs_attr *attr, char *buffer)
90 {
91 	int version = HYPERVISOR_xen_version(XENVER_version, NULL);
92 	if (version)
93 		return sprintf(buffer, "%d\n", version & 0xff);
94 	return -ENODEV;
95 }
96 
97 HYPERVISOR_ATTR_RO(minor);
98 
99 static ssize_t extra_show(struct hyp_sysfs_attr *attr, char *buffer)
100 {
101 	int ret = -ENOMEM;
102 	char *extra;
103 
104 	extra = kmalloc(XEN_EXTRAVERSION_LEN, GFP_KERNEL);
105 	if (extra) {
106 		ret = HYPERVISOR_xen_version(XENVER_extraversion, extra);
107 		if (!ret)
108 			ret = sprintf(buffer, "%s\n", extra);
109 		kfree(extra);
110 	}
111 
112 	return ret;
113 }
114 
115 HYPERVISOR_ATTR_RO(extra);
116 
117 static struct attribute *version_attrs[] = {
118 	&major_attr.attr,
119 	&minor_attr.attr,
120 	&extra_attr.attr,
121 	NULL
122 };
123 
124 static const struct attribute_group version_group = {
125 	.name = "version",
126 	.attrs = version_attrs,
127 };
128 
129 static int __init xen_sysfs_version_init(void)
130 {
131 	return sysfs_create_group(hypervisor_kobj, &version_group);
132 }
133 
134 /* UUID */
135 
136 static ssize_t uuid_show_fallback(struct hyp_sysfs_attr *attr, char *buffer)
137 {
138 	char *vm, *val;
139 	int ret;
140 	extern int xenstored_ready;
141 
142 	if (!xenstored_ready)
143 		return -EBUSY;
144 
145 	vm = xenbus_read(XBT_NIL, "vm", "", NULL);
146 	if (IS_ERR(vm))
147 		return PTR_ERR(vm);
148 	val = xenbus_read(XBT_NIL, vm, "uuid", NULL);
149 	kfree(vm);
150 	if (IS_ERR(val))
151 		return PTR_ERR(val);
152 	ret = sprintf(buffer, "%s\n", val);
153 	kfree(val);
154 	return ret;
155 }
156 
157 static ssize_t uuid_show(struct hyp_sysfs_attr *attr, char *buffer)
158 {
159 	xen_domain_handle_t uuid;
160 	int ret;
161 	ret = HYPERVISOR_xen_version(XENVER_guest_handle, uuid);
162 	if (ret)
163 		return uuid_show_fallback(attr, buffer);
164 	ret = sprintf(buffer, "%pU\n", uuid);
165 	return ret;
166 }
167 
168 HYPERVISOR_ATTR_RO(uuid);
169 
170 static int __init xen_sysfs_uuid_init(void)
171 {
172 	return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr);
173 }
174 
175 /* xen compilation attributes */
176 
177 static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer)
178 {
179 	int ret = -ENOMEM;
180 	struct xen_compile_info *info;
181 
182 	info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
183 	if (info) {
184 		ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
185 		if (!ret)
186 			ret = sprintf(buffer, "%s\n", info->compiler);
187 		kfree(info);
188 	}
189 
190 	return ret;
191 }
192 
193 HYPERVISOR_ATTR_RO(compiler);
194 
195 static ssize_t compiled_by_show(struct hyp_sysfs_attr *attr, char *buffer)
196 {
197 	int ret = -ENOMEM;
198 	struct xen_compile_info *info;
199 
200 	info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
201 	if (info) {
202 		ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
203 		if (!ret)
204 			ret = sprintf(buffer, "%s\n", info->compile_by);
205 		kfree(info);
206 	}
207 
208 	return ret;
209 }
210 
211 HYPERVISOR_ATTR_RO(compiled_by);
212 
213 static ssize_t compile_date_show(struct hyp_sysfs_attr *attr, char *buffer)
214 {
215 	int ret = -ENOMEM;
216 	struct xen_compile_info *info;
217 
218 	info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
219 	if (info) {
220 		ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
221 		if (!ret)
222 			ret = sprintf(buffer, "%s\n", info->compile_date);
223 		kfree(info);
224 	}
225 
226 	return ret;
227 }
228 
229 HYPERVISOR_ATTR_RO(compile_date);
230 
231 static struct attribute *xen_compile_attrs[] = {
232 	&compiler_attr.attr,
233 	&compiled_by_attr.attr,
234 	&compile_date_attr.attr,
235 	NULL
236 };
237 
238 static const struct attribute_group xen_compilation_group = {
239 	.name = "compilation",
240 	.attrs = xen_compile_attrs,
241 };
242 
243 static int __init xen_sysfs_compilation_init(void)
244 {
245 	return sysfs_create_group(hypervisor_kobj, &xen_compilation_group);
246 }
247 
248 /* xen properties info */
249 
250 static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer)
251 {
252 	int ret = -ENOMEM;
253 	char *caps;
254 
255 	caps = kmalloc(XEN_CAPABILITIES_INFO_LEN, GFP_KERNEL);
256 	if (caps) {
257 		ret = HYPERVISOR_xen_version(XENVER_capabilities, caps);
258 		if (!ret)
259 			ret = sprintf(buffer, "%s\n", caps);
260 		kfree(caps);
261 	}
262 
263 	return ret;
264 }
265 
266 HYPERVISOR_ATTR_RO(capabilities);
267 
268 static ssize_t changeset_show(struct hyp_sysfs_attr *attr, char *buffer)
269 {
270 	int ret = -ENOMEM;
271 	char *cset;
272 
273 	cset = kmalloc(XEN_CHANGESET_INFO_LEN, GFP_KERNEL);
274 	if (cset) {
275 		ret = HYPERVISOR_xen_version(XENVER_changeset, cset);
276 		if (!ret)
277 			ret = sprintf(buffer, "%s\n", cset);
278 		kfree(cset);
279 	}
280 
281 	return ret;
282 }
283 
284 HYPERVISOR_ATTR_RO(changeset);
285 
286 static ssize_t virtual_start_show(struct hyp_sysfs_attr *attr, char *buffer)
287 {
288 	int ret = -ENOMEM;
289 	struct xen_platform_parameters *parms;
290 
291 	parms = kmalloc(sizeof(struct xen_platform_parameters), GFP_KERNEL);
292 	if (parms) {
293 		ret = HYPERVISOR_xen_version(XENVER_platform_parameters,
294 					     parms);
295 		if (!ret)
296 			ret = sprintf(buffer, "%"PRI_xen_ulong"\n",
297 				      parms->virt_start);
298 		kfree(parms);
299 	}
300 
301 	return ret;
302 }
303 
304 HYPERVISOR_ATTR_RO(virtual_start);
305 
306 static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer)
307 {
308 	int ret;
309 
310 	ret = HYPERVISOR_xen_version(XENVER_pagesize, NULL);
311 	if (ret > 0)
312 		ret = sprintf(buffer, "%x\n", ret);
313 
314 	return ret;
315 }
316 
317 HYPERVISOR_ATTR_RO(pagesize);
318 
319 static ssize_t xen_feature_show(int index, char *buffer)
320 {
321 	ssize_t ret;
322 	struct xen_feature_info info;
323 
324 	info.submap_idx = index;
325 	ret = HYPERVISOR_xen_version(XENVER_get_features, &info);
326 	if (!ret)
327 		ret = sprintf(buffer, "%08x", info.submap);
328 
329 	return ret;
330 }
331 
332 static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
333 {
334 	ssize_t len;
335 	int i;
336 
337 	len = 0;
338 	for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) {
339 		int ret = xen_feature_show(i, buffer + len);
340 		if (ret < 0) {
341 			if (len == 0)
342 				len = ret;
343 			break;
344 		}
345 		len += ret;
346 	}
347 	if (len > 0)
348 		buffer[len++] = '\n';
349 
350 	return len;
351 }
352 
353 HYPERVISOR_ATTR_RO(features);
354 
355 static ssize_t buildid_show(struct hyp_sysfs_attr *attr, char *buffer)
356 {
357 	ssize_t ret;
358 	struct xen_build_id *buildid;
359 
360 	ret = HYPERVISOR_xen_version(XENVER_build_id, NULL);
361 	if (ret < 0) {
362 		if (ret == -EPERM)
363 			ret = sprintf(buffer, "<denied>");
364 		return ret;
365 	}
366 
367 	buildid = kmalloc(sizeof(*buildid) + ret, GFP_KERNEL);
368 	if (!buildid)
369 		return -ENOMEM;
370 
371 	buildid->len = ret;
372 	ret = HYPERVISOR_xen_version(XENVER_build_id, buildid);
373 	if (ret > 0)
374 		ret = sprintf(buffer, "%s", buildid->buf);
375 	kfree(buildid);
376 
377 	return ret;
378 }
379 
380 HYPERVISOR_ATTR_RO(buildid);
381 
382 static struct attribute *xen_properties_attrs[] = {
383 	&capabilities_attr.attr,
384 	&changeset_attr.attr,
385 	&virtual_start_attr.attr,
386 	&pagesize_attr.attr,
387 	&features_attr.attr,
388 	&buildid_attr.attr,
389 	NULL
390 };
391 
392 static const struct attribute_group xen_properties_group = {
393 	.name = "properties",
394 	.attrs = xen_properties_attrs,
395 };
396 
397 static int __init xen_sysfs_properties_init(void)
398 {
399 	return sysfs_create_group(hypervisor_kobj, &xen_properties_group);
400 }
401 
402 #ifdef CONFIG_XEN_HAVE_VPMU
403 struct pmu_mode {
404 	const char *name;
405 	uint32_t mode;
406 };
407 
408 static struct pmu_mode pmu_modes[] = {
409 	{"off", XENPMU_MODE_OFF},
410 	{"self", XENPMU_MODE_SELF},
411 	{"hv", XENPMU_MODE_HV},
412 	{"all", XENPMU_MODE_ALL}
413 };
414 
415 static ssize_t pmu_mode_store(struct hyp_sysfs_attr *attr,
416 			      const char *buffer, size_t len)
417 {
418 	int ret;
419 	struct xen_pmu_params xp;
420 	int i;
421 
422 	for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
423 		if (strncmp(buffer, pmu_modes[i].name, len - 1) == 0) {
424 			xp.val = pmu_modes[i].mode;
425 			break;
426 		}
427 	}
428 
429 	if (i == ARRAY_SIZE(pmu_modes))
430 		return -EINVAL;
431 
432 	xp.version.maj = XENPMU_VER_MAJ;
433 	xp.version.min = XENPMU_VER_MIN;
434 	ret = HYPERVISOR_xenpmu_op(XENPMU_mode_set, &xp);
435 	if (ret)
436 		return ret;
437 
438 	return len;
439 }
440 
441 static ssize_t pmu_mode_show(struct hyp_sysfs_attr *attr, char *buffer)
442 {
443 	int ret;
444 	struct xen_pmu_params xp;
445 	int i;
446 	uint32_t mode;
447 
448 	xp.version.maj = XENPMU_VER_MAJ;
449 	xp.version.min = XENPMU_VER_MIN;
450 	ret = HYPERVISOR_xenpmu_op(XENPMU_mode_get, &xp);
451 	if (ret)
452 		return ret;
453 
454 	mode = (uint32_t)xp.val;
455 	for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
456 		if (mode == pmu_modes[i].mode)
457 			return sprintf(buffer, "%s\n", pmu_modes[i].name);
458 	}
459 
460 	return -EINVAL;
461 }
462 HYPERVISOR_ATTR_RW(pmu_mode);
463 
464 static ssize_t pmu_features_store(struct hyp_sysfs_attr *attr,
465 				  const char *buffer, size_t len)
466 {
467 	int ret;
468 	uint32_t features;
469 	struct xen_pmu_params xp;
470 
471 	ret = kstrtou32(buffer, 0, &features);
472 	if (ret)
473 		return ret;
474 
475 	xp.val = features;
476 	xp.version.maj = XENPMU_VER_MAJ;
477 	xp.version.min = XENPMU_VER_MIN;
478 	ret = HYPERVISOR_xenpmu_op(XENPMU_feature_set, &xp);
479 	if (ret)
480 		return ret;
481 
482 	return len;
483 }
484 
485 static ssize_t pmu_features_show(struct hyp_sysfs_attr *attr, char *buffer)
486 {
487 	int ret;
488 	struct xen_pmu_params xp;
489 
490 	xp.version.maj = XENPMU_VER_MAJ;
491 	xp.version.min = XENPMU_VER_MIN;
492 	ret = HYPERVISOR_xenpmu_op(XENPMU_feature_get, &xp);
493 	if (ret)
494 		return ret;
495 
496 	return sprintf(buffer, "0x%x\n", (uint32_t)xp.val);
497 }
498 HYPERVISOR_ATTR_RW(pmu_features);
499 
500 static struct attribute *xen_pmu_attrs[] = {
501 	&pmu_mode_attr.attr,
502 	&pmu_features_attr.attr,
503 	NULL
504 };
505 
506 static const struct attribute_group xen_pmu_group = {
507 	.name = "pmu",
508 	.attrs = xen_pmu_attrs,
509 };
510 
511 static int __init xen_sysfs_pmu_init(void)
512 {
513 	return sysfs_create_group(hypervisor_kobj, &xen_pmu_group);
514 }
515 #endif
516 
517 static int __init hyper_sysfs_init(void)
518 {
519 	int ret;
520 
521 	if (!xen_domain())
522 		return -ENODEV;
523 
524 	ret = xen_sysfs_type_init();
525 	if (ret)
526 		goto out;
527 	ret = xen_sysfs_guest_type_init();
528 	if (ret)
529 		goto guest_type_out;
530 	ret = xen_sysfs_version_init();
531 	if (ret)
532 		goto version_out;
533 	ret = xen_sysfs_compilation_init();
534 	if (ret)
535 		goto comp_out;
536 	ret = xen_sysfs_uuid_init();
537 	if (ret)
538 		goto uuid_out;
539 	ret = xen_sysfs_properties_init();
540 	if (ret)
541 		goto prop_out;
542 #ifdef CONFIG_XEN_HAVE_VPMU
543 	if (xen_initial_domain()) {
544 		ret = xen_sysfs_pmu_init();
545 		if (ret) {
546 			sysfs_remove_group(hypervisor_kobj,
547 					   &xen_properties_group);
548 			goto prop_out;
549 		}
550 	}
551 #endif
552 	goto out;
553 
554 prop_out:
555 	sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
556 uuid_out:
557 	sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
558 comp_out:
559 	sysfs_remove_group(hypervisor_kobj, &version_group);
560 version_out:
561 	sysfs_remove_file(hypervisor_kobj, &guest_type_attr.attr);
562 guest_type_out:
563 	sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
564 out:
565 	return ret;
566 }
567 device_initcall(hyper_sysfs_init);
568 
569 static ssize_t hyp_sysfs_show(struct kobject *kobj,
570 			      struct attribute *attr,
571 			      char *buffer)
572 {
573 	struct hyp_sysfs_attr *hyp_attr;
574 	hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
575 	if (hyp_attr->show)
576 		return hyp_attr->show(hyp_attr, buffer);
577 	return 0;
578 }
579 
580 static ssize_t hyp_sysfs_store(struct kobject *kobj,
581 			       struct attribute *attr,
582 			       const char *buffer,
583 			       size_t len)
584 {
585 	struct hyp_sysfs_attr *hyp_attr;
586 	hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
587 	if (hyp_attr->store)
588 		return hyp_attr->store(hyp_attr, buffer, len);
589 	return 0;
590 }
591 
592 static const struct sysfs_ops hyp_sysfs_ops = {
593 	.show = hyp_sysfs_show,
594 	.store = hyp_sysfs_store,
595 };
596 
597 static struct kobj_type hyp_sysfs_kobj_type = {
598 	.sysfs_ops = &hyp_sysfs_ops,
599 };
600 
601 static int __init hypervisor_subsys_init(void)
602 {
603 	if (!xen_domain())
604 		return -ENODEV;
605 
606 	hypervisor_kobj->ktype = &hyp_sysfs_kobj_type;
607 	return 0;
608 }
609 device_initcall(hypervisor_subsys_init);
610