kernel/arch/powerpc/platforms/pseries/dlpar.c

   1 /*
   2  * Support for dynamic reconfiguration for PCI, Memory, and CPU
   3  * Hotplug and Dynamic Logical Partitioning on RPA platforms.
   4  *
   5  * Copyright (C) 2009 Nathan Fontenot
   6  * Copyright (C) 2009 IBM Corporation
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License version
  10  * 2 as published by the Free Software Foundation.
  11  */
  12
  13 #define pr_fmt(fmt)     "dlpar: " fmt
  14
  15 #include <linux/kernel.h>
  16 #include <linux/notifier.h>
  17 #include <linux/spinlock.h>
  18 #include <linux/cpu.h>
  19 #include <linux/slab.h>
  20 #include <linux/of.h>
  21 #include "offline_states.h"
  22 #include "pseries.h"
  23
  24 #include <asm/prom.h>
  25 #include <asm/machdep.h>
  26 #include <asm/uaccess.h>
  27 #include <asm/rtas.h>
  28
  29 struct cc_workarea {
  30         __be32  drc_index;
  31         __be32  zero;
  32         __be32  name_offset;
  33         __be32  prop_length;
  34         __be32  prop_offset;
  35 };
  36
  37 void dlpar_free_cc_property(struct property *prop)
  38 {
  39         kfree(prop->name);
  40         kfree(prop->value);
  41         kfree(prop);
  42 }
  43
  44 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
  45 {
  46         struct property *prop;
  47         char *name;
  48         char *value;
  49
  50         prop = kzalloc(sizeof(*prop), GFP_KERNEL);
  51         if (!prop)
  52                 return NULL;
  53
  54         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
  55         prop->name = kstrdup(name, GFP_KERNEL);
  56
  57         prop->length = be32_to_cpu(ccwa->prop_length);
  58         value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
  59         prop->value = kmemdup(value, prop->length, GFP_KERNEL);
  60         if (!prop->value) {
  61                 dlpar_free_cc_property(prop);
  62                 return NULL;
  63         }
  64
  65         return prop;
  66 }
  67
  68 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
  69                                                const char *path)
  70 {
  71         struct device_node *dn;
  72         char *name;
  73
  74         /* If parent node path is "/" advance path to NULL terminator to
  75          * prevent double leading slashs in full_name.
  76          */
  77         if (!path[1])
  78                 path++;
  79
  80         dn = kzalloc(sizeof(*dn), GFP_KERNEL);
  81         if (!dn)
  82                 return NULL;
  83
  84         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
  85         dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name);
  86         if (!dn->full_name) {
  87                 kfree(dn);
  88                 return NULL;
  89         }
  90
  91         of_node_set_flag(dn, OF_DYNAMIC);
  92         of_node_init(dn);
  93
  94         return dn;
  95 }
  96
  97 static void dlpar_free_one_cc_node(struct device_node *dn)
  98 {
  99         struct property *prop;
 100
 101         while (dn->properties) {
 102                 prop = dn->properties;
 103                 dn->properties = prop->next;
 104                 dlpar_free_cc_property(prop);
 105         }
 106
 107         kfree(dn->full_name);
 108         kfree(dn);
 109 }
 110
 111 void dlpar_free_cc_nodes(struct device_node *dn)
 112 {
 113         if (dn->child)
 114                 dlpar_free_cc_nodes(dn->child);
 115
 116         if (dn->sibling)
 117                 dlpar_free_cc_nodes(dn->sibling);
 118
 119         dlpar_free_one_cc_node(dn);
 120 }
 121
 122 #define COMPLETE        0
 123 #define NEXT_SIBLING    1
 124 #define NEXT_CHILD      2
 125 #define NEXT_PROPERTY   3
 126 #define PREV_PARENT     4
 127 #define MORE_MEMORY     5
 128 #define CALL_AGAIN      -2
 129 #define ERR_CFG_USE     -9003
 130
 131 struct device_node *dlpar_configure_connector(__be32 drc_index,
 132                                               struct device_node *parent)
 133 {
 134         struct device_node *dn;
 135         struct device_node *first_dn = NULL;
 136         struct device_node *last_dn = NULL;
 137         struct property *property;
 138         struct property *last_property = NULL;
 139         struct cc_workarea *ccwa;
 140         char *data_buf;
 141         const char *parent_path = parent->full_name;
 142         int cc_token;
 143         int rc = -1;
 144
 145         cc_token = rtas_token("ibm,configure-connector");
 146         if (cc_token == RTAS_UNKNOWN_SERVICE)
 147                 return NULL;
 148
 149         data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 150         if (!data_buf)
 151                 return NULL;
 152
 153         ccwa = (struct cc_workarea *)&data_buf[0];
 154         ccwa->drc_index = drc_index;
 155         ccwa->zero = 0;
 156
 157         do {
 158                 /* Since we release the rtas_data_buf lock between configure
 159                  * connector calls we want to re-populate the rtas_data_buffer
 160                  * with the contents of the previous call.
 161                  */
 162                 spin_lock(&rtas_data_buf_lock);
 163
 164                 memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
 165                 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
 166                 memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
 167
 168                 spin_unlock(&rtas_data_buf_lock);
 169
 170                 switch (rc) {
 171                 case COMPLETE:
 172                         break;
 173
 174                 case NEXT_SIBLING:
 175                         dn = dlpar_parse_cc_node(ccwa, parent_path);
 176                         if (!dn)
 177                                 goto cc_error;
 178
 179                         dn->parent = last_dn->parent;
 180                         last_dn->sibling = dn;
 181                         last_dn = dn;
 182                         break;
 183
 184                 case NEXT_CHILD:
 185                         if (first_dn)
 186                                 parent_path = last_dn->full_name;
 187
 188                         dn = dlpar_parse_cc_node(ccwa, parent_path);
 189                         if (!dn)
 190                                 goto cc_error;
 191
 192                         if (!first_dn) {
 193                                 dn->parent = parent;
 194                                 first_dn = dn;
 195                         } else {
 196                                 dn->parent = last_dn;
 197                                 if (last_dn)
 198                                         last_dn->child = dn;
 199                         }
 200
 201                         last_dn = dn;
 202                         break;
 203
 204                 case NEXT_PROPERTY:
 205                         property = dlpar_parse_cc_property(ccwa);
 206                         if (!property)
 207                                 goto cc_error;
 208
 209                         if (!last_dn->properties)
 210                                 last_dn->properties = property;
 211                         else
 212                                 last_property->next = property;
 213
 214                         last_property = property;
 215                         break;
 216
 217                 case PREV_PARENT:
 218                         last_dn = last_dn->parent;
 219                         parent_path = last_dn->parent->full_name;
 220                         break;
 221
 222                 case CALL_AGAIN:
 223                         break;
 224
 225                 case MORE_MEMORY:
 226                 case ERR_CFG_USE:
 227                 default:
 228                         printk(KERN_ERR "Unexpected Error (%d) "
 229                                "returned from configure-connector\n", rc);
 230                         goto cc_error;
 231                 }
 232         } while (rc);
 233
 234 cc_error:
 235         kfree(data_buf);
 236
 237         if (rc) {
 238                 if (first_dn)
 239                         dlpar_free_cc_nodes(first_dn);
 240
 241                 return NULL;
 242         }
 243
 244         return first_dn;
 245 }
 246
 247 static struct device_node *derive_parent(const char *path)
 248 {
 249         struct device_node *parent;
 250         char *last_slash;
 251
 252         last_slash = strrchr(path, '/');
 253         if (last_slash == path) {
 254                 parent = of_find_node_by_path("/");
 255         } else {
 256                 char *parent_path;
 257                 int parent_path_len = last_slash - path + 1;
 258                 parent_path = kmalloc(parent_path_len, GFP_KERNEL);
 259                 if (!parent_path)
 260                         return NULL;
 261
 262                 strlcpy(parent_path, path, parent_path_len);
 263                 parent = of_find_node_by_path(parent_path);
 264                 kfree(parent_path);
 265         }
 266
 267         return parent;
 268 }
 269
 270 int dlpar_attach_node(struct device_node *dn)
 271 {
 272         int rc;
 273
 274         dn->parent = derive_parent(dn->full_name);
 275         if (!dn->parent)
 276                 return -ENOMEM;
 277
 278         rc = of_attach_node(dn);
 279         if (rc) {
 280                 printk(KERN_ERR "Failed to add device node %s\n",
 281                        dn->full_name);
 282                 return rc;
 283         }
 284
 285         of_node_put(dn->parent);
 286         return 0;
 287 }
 288
 289 int dlpar_detach_node(struct device_node *dn)
 290 {
 291         struct device_node *child;
 292         int rc;
 293
 294         child = of_get_next_child(dn, NULL);
 295         while (child) {
 296                 dlpar_detach_node(child);
 297                 child = of_get_next_child(dn, child);
 298         }
 299
 300         rc = of_detach_node(dn);
 301         if (rc)
 302                 return rc;
 303
 304         of_node_put(dn); /* Must decrement the refcount */
 305         return 0;
 306 }
 307
 308 #define DR_ENTITY_SENSE         9003
 309 #define DR_ENTITY_PRESENT       1
 310 #define DR_ENTITY_UNUSABLE      2
 311 #define ALLOCATION_STATE        9003
 312 #define ALLOC_UNUSABLE          0
 313 #define ALLOC_USABLE            1
 314 #define ISOLATION_STATE         9001
 315 #define ISOLATE                 0
 316 #define UNISOLATE               1
 317
 318 int dlpar_acquire_drc(u32 drc_index)
 319 {
 320         int dr_status, rc;
 321
 322         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
 323                        DR_ENTITY_SENSE, drc_index);
 324         if (rc || dr_status != DR_ENTITY_UNUSABLE)
 325                 return -1;
 326
 327         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
 328         if (rc)
 329                 return rc;
 330
 331         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
 332         if (rc) {
 333                 rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
 334                 return rc;
 335         }
 336
 337         return 0;
 338 }
 339
 340 int dlpar_release_drc(u32 drc_index)
 341 {
 342         int dr_status, rc;
 343
 344         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
 345                        DR_ENTITY_SENSE, drc_index);
 346         if (rc || dr_status != DR_ENTITY_PRESENT)
 347                 return -1;
 348
 349         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
 350         if (rc)
 351                 return rc;
 352
 353         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
 354         if (rc) {
 355                 rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
 356                 return rc;
 357         }
 358
 359         return 0;
 360 }
 361
 362 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 363
 364 static int dlpar_online_cpu(struct device_node *dn)
 365 {
 366         int rc = 0;
 367         unsigned int cpu;
 368         int len, nthreads, i;
 369         const __be32 *intserv;
 370         u32 thread;
 371
 372         intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
 373         if (!intserv)
 374                 return -EINVAL;
 375
 376         nthreads = len / sizeof(u32);
 377
 378         cpu_maps_update_begin();
 379         for (i = 0; i < nthreads; i++) {
 380                 thread = be32_to_cpu(intserv[i]);
 381                 for_each_present_cpu(cpu) {
 382                         if (get_hard_smp_processor_id(cpu) != thread)
 383                                 continue;
 384                         BUG_ON(get_cpu_current_state(cpu)
 385                                         != CPU_STATE_OFFLINE);
 386                         cpu_maps_update_done();
 387                         rc = device_online(get_cpu_device(cpu));
 388                         if (rc)
 389                                 goto out;
 390                         cpu_maps_update_begin();
 391
 392                         break;
 393                 }
 394                 if (cpu == num_possible_cpus())
 395                         printk(KERN_WARNING "Could not find cpu to online "
 396                                "with physical id 0x%x\n", thread);
 397         }
 398         cpu_maps_update_done();
 399
 400 out:
 401         return rc;
 402
 403 }
 404
 405 static ssize_t dlpar_cpu_probe(const char *buf, size_t count)
 406 {
 407         struct device_node *dn, *parent;
 408         u32 drc_index;
 409         int rc;
 410
 411         rc = kstrtou32(buf, 0, &drc_index);
 412         if (rc)
 413                 return -EINVAL;
 414
 415         rc = dlpar_acquire_drc(drc_index);
 416         if (rc)
 417                 return -EINVAL;
 418
 419         parent = of_find_node_by_path("/cpus");
 420         if (!parent)
 421                 return -ENODEV;
 422
 423         dn = dlpar_configure_connector(cpu_to_be32(drc_index), parent);
 424         if (!dn)
 425                 return -EINVAL;
 426
 427         of_node_put(parent);
 428
 429         rc = dlpar_attach_node(dn);
 430         if (rc) {
 431                 dlpar_release_drc(drc_index);
 432                 dlpar_free_cc_nodes(dn);
 433                 return rc;
 434         }
 435
 436         rc = dlpar_online_cpu(dn);
 437         if (rc)
 438                 return rc;
 439
 440         return count;
 441 }
 442
 443 static int dlpar_offline_cpu(struct device_node *dn)
 444 {
 445         int rc = 0;
 446         unsigned int cpu;
 447         int len, nthreads, i;
 448         const __be32 *intserv;
 449         u32 thread;
 450
 451         intserv = of_get_property(dn, "ibm,ppc-interrupt-server#s", &len);
 452         if (!intserv)
 453                 return -EINVAL;
 454
 455         nthreads = len / sizeof(u32);
 456
 457         cpu_maps_update_begin();
 458         for (i = 0; i < nthreads; i++) {
 459                 thread = be32_to_cpu(intserv[i]);
 460                 for_each_present_cpu(cpu) {
 461                         if (get_hard_smp_processor_id(cpu) != thread)
 462                                 continue;
 463
 464                         if (get_cpu_current_state(cpu) == CPU_STATE_OFFLINE)
 465                                 break;
 466
 467                         if (get_cpu_current_state(cpu) == CPU_STATE_ONLINE) {
 468                                 set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
 469                                 cpu_maps_update_done();
 470                                 rc = device_offline(get_cpu_device(cpu));
 471                                 if (rc)
 472                                         goto out;
 473                                 cpu_maps_update_begin();
 474                                 break;
 475
 476                         }
 477
 478                         /*
 479                          * The cpu is in CPU_STATE_INACTIVE.
 480                          * Upgrade it's state to CPU_STATE_OFFLINE.
 481                          */
 482                         set_preferred_offline_state(cpu, CPU_STATE_OFFLINE);
 483                         BUG_ON(plpar_hcall_norets(H_PROD, thread)
 484                                                                 != H_SUCCESS);
 485                         __cpu_die(cpu);
 486                         break;
 487                 }
 488                 if (cpu == num_possible_cpus())
 489                         printk(KERN_WARNING "Could not find cpu to offline "
 490                                "with physical id 0x%x\n", thread);
 491         }
 492         cpu_maps_update_done();
 493
 494 out:
 495         return rc;
 496
 497 }
 498
 499 static ssize_t dlpar_cpu_release(const char *buf, size_t count)
 500 {
 501         struct device_node *dn;
 502         u32 drc_index;
 503         int rc;
 504
 505         dn = of_find_node_by_path(buf);
 506         if (!dn)
 507                 return -EINVAL;
 508
 509         rc = of_property_read_u32(dn, "ibm,my-drc-index", &drc_index);
 510         if (rc) {
 511                 of_node_put(dn);
 512                 return -EINVAL;
 513         }
 514
 515         rc = dlpar_offline_cpu(dn);
 516         if (rc) {
 517                 of_node_put(dn);
 518                 return -EINVAL;
 519         }
 520
 521         rc = dlpar_release_drc(drc_index);
 522         if (rc) {
 523                 of_node_put(dn);
 524                 return rc;
 525         }
 526
 527         rc = dlpar_detach_node(dn);
 528         if (rc) {
 529                 dlpar_acquire_drc(drc_index);
 530                 return rc;
 531         }
 532
 533         of_node_put(dn);
 534
 535         return count;
 536 }
 537
 538 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
 539
 540 static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
 541 {
 542         int rc;
 543
 544         /* pseries error logs are in BE format, convert to cpu type */
 545         switch (hp_elog->id_type) {
 546         case PSERIES_HP_ELOG_ID_DRC_COUNT:
 547                 hp_elog->_drc_u.drc_count =
 548                                         be32_to_cpu(hp_elog->_drc_u.drc_count);
 549                 break;
 550         case PSERIES_HP_ELOG_ID_DRC_INDEX:
 551                 hp_elog->_drc_u.drc_index =
 552                                         be32_to_cpu(hp_elog->_drc_u.drc_index);
 553         }
 554
 555         switch (hp_elog->resource) {
 556         case PSERIES_HP_ELOG_RESOURCE_MEM:
 557                 rc = dlpar_memory(hp_elog);
 558                 break;
 559         default:
 560                 pr_warn_ratelimited("Invalid resource (%d) specified\n",
 561                                     hp_elog->resource);
 562                 rc = -EINVAL;
 563         }
 564
 565         return rc;
 566 }
 567
 568 static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
 569                            const char *buf, size_t count)
 570 {
 571         struct pseries_hp_errorlog *hp_elog;
 572         const char *arg;
 573         int rc;
 574
 575         hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
 576         if (!hp_elog) {
 577                 rc = -ENOMEM;
 578                 goto dlpar_store_out;
 579         }
 580
 581         /* Parse out the request from the user, this will be in the form
 582          * <resource> <action> <id_type> <id>
 583          */
 584         arg = buf;
 585         if (!strncmp(arg, "memory", 6)) {
 586                 hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
 587                 arg += strlen("memory ");
 588         } else {
 589                 pr_err("Invalid resource specified: \"%s\"\n", buf);
 590                 rc = -EINVAL;
 591                 goto dlpar_store_out;
 592         }
 593
 594         if (!strncmp(arg, "add", 3)) {
 595                 hp_elog->action = PSERIES_HP_ELOG_ACTION_ADD;
 596                 arg += strlen("add ");
 597         } else if (!strncmp(arg, "remove", 6)) {
 598                 hp_elog->action = PSERIES_HP_ELOG_ACTION_REMOVE;
 599                 arg += strlen("remove ");
 600         } else {
 601                 pr_err("Invalid action specified: \"%s\"\n", buf);
 602                 rc = -EINVAL;
 603                 goto dlpar_store_out;
 604         }
 605
 606         if (!strncmp(arg, "index", 5)) {
 607                 u32 index;
 608
 609                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
 610                 arg += strlen("index ");
 611                 if (kstrtou32(arg, 0, &index)) {
 612                         rc = -EINVAL;
 613                         pr_err("Invalid drc_index specified: \"%s\"\n", buf);
 614                         goto dlpar_store_out;
 615                 }
 616
 617                 hp_elog->_drc_u.drc_index = cpu_to_be32(index);
 618         } else if (!strncmp(arg, "count", 5)) {
 619                 u32 count;
 620
 621                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_COUNT;
 622                 arg += strlen("count ");
 623                 if (kstrtou32(arg, 0, &count)) {
 624                         rc = -EINVAL;
 625                         pr_err("Invalid count specified: \"%s\"\n", buf);
 626                         goto dlpar_store_out;
 627                 }
 628
 629                 hp_elog->_drc_u.drc_count = cpu_to_be32(count);
 630         } else {
 631                 pr_err("Invalid id_type specified: \"%s\"\n", buf);
 632                 rc = -EINVAL;
 633                 goto dlpar_store_out;
 634         }
 635
 636         rc = handle_dlpar_errorlog(hp_elog);
 637
 638 dlpar_store_out:
 639         kfree(hp_elog);
 640         return rc ? rc : count;
 641 }
 642
 643 static CLASS_ATTR(dlpar, S_IWUSR, NULL, dlpar_store);
 644
 645 static int __init pseries_dlpar_init(void)
 646 {
 647         int rc;
 648
 649 #ifdef CONFIG_ARCH_CPU_PROBE_RELEASE
 650         ppc_md.cpu_probe = dlpar_cpu_probe;
 651         ppc_md.cpu_release = dlpar_cpu_release;
 652 #endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
 653
 654         rc = sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
 655
 656         return rc;
 657 }
 658 machine_device_initcall(pseries, pseries_dlpar_init);
 659