drivers/xen/sys-hypervisor.c

   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 = \
  29         __ATTR(_name, 0644, _name##_show, _name##_store)
  30
  31 struct hyp_sysfs_attr {
  32         struct attribute attr;
  33         ssize_t (*show)(struct hyp_sysfs_attr *, char *);
  34         ssize_t (*store)(struct hyp_sysfs_attr *, const char *, size_t);
  35         void *hyp_attr_data;
  36 };
  37
  38 static ssize_t type_show(struct hyp_sysfs_attr *attr, char *buffer)
  39 {
  40         return sprintf(buffer, "xen\n");
  41 }
  42
  43 HYPERVISOR_ATTR_RO(type);
  44
  45 static int __init xen_sysfs_type_init(void)
  46 {
  47         return sysfs_create_file(hypervisor_kobj, &type_attr.attr);
  48 }
  49
  50 static ssize_t guest_type_show(struct hyp_sysfs_attr *attr, char *buffer)
  51 {
  52         const char *type;
  53
  54         switch (xen_domain_type) {
  55         case XEN_NATIVE:
  56                 /* ARM only. */
  57                 type = "Xen";
  58                 break;
  59         case XEN_PV_DOMAIN:
  60                 type = "PV";
  61                 break;
  62         case XEN_HVM_DOMAIN:
  63                 type = xen_pvh_domain() ? "PVH" : "HVM";
  64                 break;
  65         default:
  66                 return -EINVAL;
  67         }
  68
  69         return sprintf(buffer, "%s\n", type);
  70 }
  71
  72 HYPERVISOR_ATTR_RO(guest_type);
  73
  74 static int __init xen_sysfs_guest_type_init(void)
  75 {
  76         return sysfs_create_file(hypervisor_kobj, &guest_type_attr.attr);
  77 }
  78
  79 /* xen version attributes */
  80 static ssize_t major_show(struct hyp_sysfs_attr *attr, char *buffer)
  81 {
  82         int version = HYPERVISOR_xen_version(XENVER_version, NULL);
  83         if (version)
  84                 return sprintf(buffer, "%d\n", version >> 16);
  85         return -ENODEV;
  86 }
  87
  88 HYPERVISOR_ATTR_RO(major);
  89
  90 static ssize_t minor_show(struct hyp_sysfs_attr *attr, char *buffer)
  91 {
  92         int version = HYPERVISOR_xen_version(XENVER_version, NULL);
  93         if (version)
  94                 return sprintf(buffer, "%d\n", version & 0xff);
  95         return -ENODEV;
  96 }
  97
  98 HYPERVISOR_ATTR_RO(minor);
  99
 100 static ssize_t extra_show(struct hyp_sysfs_attr *attr, char *buffer)
 101 {
 102         int ret = -ENOMEM;
 103         char *extra;
 104
 105         extra = kmalloc(XEN_EXTRAVERSION_LEN, GFP_KERNEL);
 106         if (extra) {
 107                 ret = HYPERVISOR_xen_version(XENVER_extraversion, extra);
 108                 if (!ret)
 109                         ret = sprintf(buffer, "%s\n", extra);
 110                 kfree(extra);
 111         }
 112
 113         return ret;
 114 }
 115
 116 HYPERVISOR_ATTR_RO(extra);
 117
 118 static struct attribute *version_attrs[] = {
 119         &major_attr.attr,
 120         &minor_attr.attr,
 121         &extra_attr.attr,
 122         NULL
 123 };
 124
 125 static const struct attribute_group version_group = {
 126         .name = "version",
 127         .attrs = version_attrs,
 128 };
 129
 130 static int __init xen_sysfs_version_init(void)
 131 {
 132         return sysfs_create_group(hypervisor_kobj, &version_group);
 133 }
 134
 135 /* UUID */
 136
 137 static ssize_t uuid_show_fallback(struct hyp_sysfs_attr *attr, char *buffer)
 138 {
 139         char *vm, *val;
 140         int ret;
 141         extern int xenstored_ready;
 142
 143         if (!xenstored_ready)
 144                 return -EBUSY;
 145
 146         vm = xenbus_read(XBT_NIL, "vm", "", NULL);
 147         if (IS_ERR(vm))
 148                 return PTR_ERR(vm);
 149         val = xenbus_read(XBT_NIL, vm, "uuid", NULL);
 150         kfree(vm);
 151         if (IS_ERR(val))
 152                 return PTR_ERR(val);
 153         ret = sprintf(buffer, "%s\n", val);
 154         kfree(val);
 155         return ret;
 156 }
 157
 158 static ssize_t uuid_show(struct hyp_sysfs_attr *attr, char *buffer)
 159 {
 160         xen_domain_handle_t uuid;
 161         int ret;
 162         ret = HYPERVISOR_xen_version(XENVER_guest_handle, uuid);
 163         if (ret)
 164                 return uuid_show_fallback(attr, buffer);
 165         ret = sprintf(buffer, "%pU\n", uuid);
 166         return ret;
 167 }
 168
 169 HYPERVISOR_ATTR_RO(uuid);
 170
 171 static int __init xen_sysfs_uuid_init(void)
 172 {
 173         return sysfs_create_file(hypervisor_kobj, &uuid_attr.attr);
 174 }
 175
 176 /* xen compilation attributes */
 177
 178 static ssize_t compiler_show(struct hyp_sysfs_attr *attr, char *buffer)
 179 {
 180         int ret = -ENOMEM;
 181         struct xen_compile_info *info;
 182
 183         info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
 184         if (info) {
 185                 ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
 186                 if (!ret)
 187                         ret = sprintf(buffer, "%s\n", info->compiler);
 188                 kfree(info);
 189         }
 190
 191         return ret;
 192 }
 193
 194 HYPERVISOR_ATTR_RO(compiler);
 195
 196 static ssize_t compiled_by_show(struct hyp_sysfs_attr *attr, char *buffer)
 197 {
 198         int ret = -ENOMEM;
 199         struct xen_compile_info *info;
 200
 201         info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
 202         if (info) {
 203                 ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
 204                 if (!ret)
 205                         ret = sprintf(buffer, "%s\n", info->compile_by);
 206                 kfree(info);
 207         }
 208
 209         return ret;
 210 }
 211
 212 HYPERVISOR_ATTR_RO(compiled_by);
 213
 214 static ssize_t compile_date_show(struct hyp_sysfs_attr *attr, char *buffer)
 215 {
 216         int ret = -ENOMEM;
 217         struct xen_compile_info *info;
 218
 219         info = kmalloc(sizeof(struct xen_compile_info), GFP_KERNEL);
 220         if (info) {
 221                 ret = HYPERVISOR_xen_version(XENVER_compile_info, info);
 222                 if (!ret)
 223                         ret = sprintf(buffer, "%s\n", info->compile_date);
 224                 kfree(info);
 225         }
 226
 227         return ret;
 228 }
 229
 230 HYPERVISOR_ATTR_RO(compile_date);
 231
 232 static struct attribute *xen_compile_attrs[] = {
 233         &compiler_attr.attr,
 234         &compiled_by_attr.attr,
 235         &compile_date_attr.attr,
 236         NULL
 237 };
 238
 239 static const struct attribute_group xen_compilation_group = {
 240         .name = "compilation",
 241         .attrs = xen_compile_attrs,
 242 };
 243
 244 static int __init xen_sysfs_compilation_init(void)
 245 {
 246         return sysfs_create_group(hypervisor_kobj, &xen_compilation_group);
 247 }
 248
 249 /* xen properties info */
 250
 251 static ssize_t capabilities_show(struct hyp_sysfs_attr *attr, char *buffer)
 252 {
 253         int ret = -ENOMEM;
 254         char *caps;
 255
 256         caps = kmalloc(XEN_CAPABILITIES_INFO_LEN, GFP_KERNEL);
 257         if (caps) {
 258                 ret = HYPERVISOR_xen_version(XENVER_capabilities, caps);
 259                 if (!ret)
 260                         ret = sprintf(buffer, "%s\n", caps);
 261                 kfree(caps);
 262         }
 263
 264         return ret;
 265 }
 266
 267 HYPERVISOR_ATTR_RO(capabilities);
 268
 269 static ssize_t changeset_show(struct hyp_sysfs_attr *attr, char *buffer)
 270 {
 271         int ret = -ENOMEM;
 272         char *cset;
 273
 274         cset = kmalloc(XEN_CHANGESET_INFO_LEN, GFP_KERNEL);
 275         if (cset) {
 276                 ret = HYPERVISOR_xen_version(XENVER_changeset, cset);
 277                 if (!ret)
 278                         ret = sprintf(buffer, "%s\n", cset);
 279                 kfree(cset);
 280         }
 281
 282         return ret;
 283 }
 284
 285 HYPERVISOR_ATTR_RO(changeset);
 286
 287 static ssize_t virtual_start_show(struct hyp_sysfs_attr *attr, char *buffer)
 288 {
 289         int ret = -ENOMEM;
 290         struct xen_platform_parameters *parms;
 291
 292         parms = kmalloc(sizeof(struct xen_platform_parameters), GFP_KERNEL);
 293         if (parms) {
 294                 ret = HYPERVISOR_xen_version(XENVER_platform_parameters,
 295                                              parms);
 296                 if (!ret)
 297                         ret = sprintf(buffer, "%"PRI_xen_ulong"\n",
 298                                       parms->virt_start);
 299                 kfree(parms);
 300         }
 301
 302         return ret;
 303 }
 304
 305 HYPERVISOR_ATTR_RO(virtual_start);
 306
 307 static ssize_t pagesize_show(struct hyp_sysfs_attr *attr, char *buffer)
 308 {
 309         int ret;
 310
 311         ret = HYPERVISOR_xen_version(XENVER_pagesize, NULL);
 312         if (ret > 0)
 313                 ret = sprintf(buffer, "%x\n", ret);
 314
 315         return ret;
 316 }
 317
 318 HYPERVISOR_ATTR_RO(pagesize);
 319
 320 static ssize_t xen_feature_show(int index, char *buffer)
 321 {
 322         ssize_t ret;
 323         struct xen_feature_info info;
 324
 325         info.submap_idx = index;
 326         ret = HYPERVISOR_xen_version(XENVER_get_features, &info);
 327         if (!ret)
 328                 ret = sprintf(buffer, "%08x", info.submap);
 329
 330         return ret;
 331 }
 332
 333 static ssize_t features_show(struct hyp_sysfs_attr *attr, char *buffer)
 334 {
 335         ssize_t len;
 336         int i;
 337
 338         len = 0;
 339         for (i = XENFEAT_NR_SUBMAPS-1; i >= 0; i--) {
 340                 int ret = xen_feature_show(i, buffer + len);
 341                 if (ret < 0) {
 342                         if (len == 0)
 343                                 len = ret;
 344                         break;
 345                 }
 346                 len += ret;
 347         }
 348         if (len > 0)
 349                 buffer[len++] = '\n';
 350
 351         return len;
 352 }
 353
 354 HYPERVISOR_ATTR_RO(features);
 355
 356 static ssize_t buildid_show(struct hyp_sysfs_attr *attr, char *buffer)
 357 {
 358         ssize_t ret;
 359         struct xen_build_id *buildid;
 360
 361         ret = HYPERVISOR_xen_version(XENVER_build_id, NULL);
 362         if (ret < 0) {
 363                 if (ret == -EPERM)
 364                         ret = sprintf(buffer, "<denied>");
 365                 return ret;
 366         }
 367
 368         buildid = kmalloc(sizeof(*buildid) + ret, GFP_KERNEL);
 369         if (!buildid)
 370                 return -ENOMEM;
 371
 372         buildid->len = ret;
 373         ret = HYPERVISOR_xen_version(XENVER_build_id, buildid);
 374         if (ret > 0)
 375                 ret = sprintf(buffer, "%s", buildid->buf);
 376         kfree(buildid);
 377
 378         return ret;
 379 }
 380
 381 HYPERVISOR_ATTR_RO(buildid);
 382
 383 static struct attribute *xen_properties_attrs[] = {
 384         &capabilities_attr.attr,
 385         &changeset_attr.attr,
 386         &virtual_start_attr.attr,
 387         &pagesize_attr.attr,
 388         &features_attr.attr,
 389         &buildid_attr.attr,
 390         NULL
 391 };
 392
 393 static const struct attribute_group xen_properties_group = {
 394         .name = "properties",
 395         .attrs = xen_properties_attrs,
 396 };
 397
 398 static int __init xen_sysfs_properties_init(void)
 399 {
 400         return sysfs_create_group(hypervisor_kobj, &xen_properties_group);
 401 }
 402
 403 #ifdef CONFIG_XEN_HAVE_VPMU
 404 struct pmu_mode {
 405         const char *name;
 406         uint32_t mode;
 407 };
 408
 409 static struct pmu_mode pmu_modes[] = {
 410         {"off", XENPMU_MODE_OFF},
 411         {"self", XENPMU_MODE_SELF},
 412         {"hv", XENPMU_MODE_HV},
 413         {"all", XENPMU_MODE_ALL}
 414 };
 415
 416 static ssize_t pmu_mode_store(struct hyp_sysfs_attr *attr,
 417                               const char *buffer, size_t len)
 418 {
 419         int ret;
 420         struct xen_pmu_params xp;
 421         int i;
 422
 423         for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
 424                 if (strncmp(buffer, pmu_modes[i].name, len - 1) == 0) {
 425                         xp.val = pmu_modes[i].mode;
 426                         break;
 427                 }
 428         }
 429
 430         if (i == ARRAY_SIZE(pmu_modes))
 431                 return -EINVAL;
 432
 433         xp.version.maj = XENPMU_VER_MAJ;
 434         xp.version.min = XENPMU_VER_MIN;
 435         ret = HYPERVISOR_xenpmu_op(XENPMU_mode_set, &xp);
 436         if (ret)
 437                 return ret;
 438
 439         return len;
 440 }
 441
 442 static ssize_t pmu_mode_show(struct hyp_sysfs_attr *attr, char *buffer)
 443 {
 444         int ret;
 445         struct xen_pmu_params xp;
 446         int i;
 447         uint32_t mode;
 448
 449         xp.version.maj = XENPMU_VER_MAJ;
 450         xp.version.min = XENPMU_VER_MIN;
 451         ret = HYPERVISOR_xenpmu_op(XENPMU_mode_get, &xp);
 452         if (ret)
 453                 return ret;
 454
 455         mode = (uint32_t)xp.val;
 456         for (i = 0; i < ARRAY_SIZE(pmu_modes); i++) {
 457                 if (mode == pmu_modes[i].mode)
 458                         return sprintf(buffer, "%s\n", pmu_modes[i].name);
 459         }
 460
 461         return -EINVAL;
 462 }
 463 HYPERVISOR_ATTR_RW(pmu_mode);
 464
 465 static ssize_t pmu_features_store(struct hyp_sysfs_attr *attr,
 466                                   const char *buffer, size_t len)
 467 {
 468         int ret;
 469         uint32_t features;
 470         struct xen_pmu_params xp;
 471
 472         ret = kstrtou32(buffer, 0, &features);
 473         if (ret)
 474                 return ret;
 475
 476         xp.val = features;
 477         xp.version.maj = XENPMU_VER_MAJ;
 478         xp.version.min = XENPMU_VER_MIN;
 479         ret = HYPERVISOR_xenpmu_op(XENPMU_feature_set, &xp);
 480         if (ret)
 481                 return ret;
 482
 483         return len;
 484 }
 485
 486 static ssize_t pmu_features_show(struct hyp_sysfs_attr *attr, char *buffer)
 487 {
 488         int ret;
 489         struct xen_pmu_params xp;
 490
 491         xp.version.maj = XENPMU_VER_MAJ;
 492         xp.version.min = XENPMU_VER_MIN;
 493         ret = HYPERVISOR_xenpmu_op(XENPMU_feature_get, &xp);
 494         if (ret)
 495                 return ret;
 496
 497         return sprintf(buffer, "0x%x\n", (uint32_t)xp.val);
 498 }
 499 HYPERVISOR_ATTR_RW(pmu_features);
 500
 501 static struct attribute *xen_pmu_attrs[] = {
 502         &pmu_mode_attr.attr,
 503         &pmu_features_attr.attr,
 504         NULL
 505 };
 506
 507 static const struct attribute_group xen_pmu_group = {
 508         .name = "pmu",
 509         .attrs = xen_pmu_attrs,
 510 };
 511
 512 static int __init xen_sysfs_pmu_init(void)
 513 {
 514         return sysfs_create_group(hypervisor_kobj, &xen_pmu_group);
 515 }
 516 #endif
 517
 518 static int __init hyper_sysfs_init(void)
 519 {
 520         int ret;
 521
 522         if (!xen_domain())
 523                 return -ENODEV;
 524
 525         ret = xen_sysfs_type_init();
 526         if (ret)
 527                 goto out;
 528         ret = xen_sysfs_guest_type_init();
 529         if (ret)
 530                 goto guest_type_out;
 531         ret = xen_sysfs_version_init();
 532         if (ret)
 533                 goto version_out;
 534         ret = xen_sysfs_compilation_init();
 535         if (ret)
 536                 goto comp_out;
 537         ret = xen_sysfs_uuid_init();
 538         if (ret)
 539                 goto uuid_out;
 540         ret = xen_sysfs_properties_init();
 541         if (ret)
 542                 goto prop_out;
 543 #ifdef CONFIG_XEN_HAVE_VPMU
 544         if (xen_initial_domain()) {
 545                 ret = xen_sysfs_pmu_init();
 546                 if (ret) {
 547                         sysfs_remove_group(hypervisor_kobj,
 548                                            &xen_properties_group);
 549                         goto prop_out;
 550                 }
 551         }
 552 #endif
 553         goto out;
 554
 555 prop_out:
 556         sysfs_remove_file(hypervisor_kobj, &uuid_attr.attr);
 557 uuid_out:
 558         sysfs_remove_group(hypervisor_kobj, &xen_compilation_group);
 559 comp_out:
 560         sysfs_remove_group(hypervisor_kobj, &version_group);
 561 version_out:
 562         sysfs_remove_file(hypervisor_kobj, &guest_type_attr.attr);
 563 guest_type_out:
 564         sysfs_remove_file(hypervisor_kobj, &type_attr.attr);
 565 out:
 566         return ret;
 567 }
 568 device_initcall(hyper_sysfs_init);
 569
 570 static ssize_t hyp_sysfs_show(struct kobject *kobj,
 571                               struct attribute *attr,
 572                               char *buffer)
 573 {
 574         struct hyp_sysfs_attr *hyp_attr;
 575         hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
 576         if (hyp_attr->show)
 577                 return hyp_attr->show(hyp_attr, buffer);
 578         return 0;
 579 }
 580
 581 static ssize_t hyp_sysfs_store(struct kobject *kobj,
 582                                struct attribute *attr,
 583                                const char *buffer,
 584                                size_t len)
 585 {
 586         struct hyp_sysfs_attr *hyp_attr;
 587         hyp_attr = container_of(attr, struct hyp_sysfs_attr, attr);
 588         if (hyp_attr->store)
 589                 return hyp_attr->store(hyp_attr, buffer, len);
 590         return 0;
 591 }
 592
 593 static const struct sysfs_ops hyp_sysfs_ops = {
 594         .show = hyp_sysfs_show,
 595         .store = hyp_sysfs_store,
 596 };
 597
 598 static struct kobj_type hyp_sysfs_kobj_type = {
 599         .sysfs_ops = &hyp_sysfs_ops,
 600 };
 601
 602 static int __init hypervisor_subsys_init(void)
 603 {
 604         if (!xen_domain())
 605                 return -ENODEV;
 606
 607         hypervisor_kobj->ktype = &hyp_sysfs_kobj_type;
 608         return 0;
 609 }
 610 device_initcall(hypervisor_subsys_init);