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 = __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);