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
  22 #include "of_helpers.h"
  23 #include "pseries.h"
  24
  25 #include <asm/prom.h>
  26 #include <asm/machdep.h>
  27 #include <linux/uaccess.h>
  28 #include <asm/rtas.h>
  29
  30 static struct workqueue_struct *pseries_hp_wq;
  31
  32 struct pseries_hp_work {
  33         struct work_struct work;
  34         struct pseries_hp_errorlog *errlog;
  35         struct completion *hp_completion;
  36         int *rc;
  37 };
  38
  39 struct cc_workarea {
  40         __be32  drc_index;
  41         __be32  zero;
  42         __be32  name_offset;
  43         __be32  prop_length;
  44         __be32  prop_offset;
  45 };
  46
  47 void dlpar_free_cc_property(struct property *prop)
  48 {
  49         kfree(prop->name);
  50         kfree(prop->value);
  51         kfree(prop);
  52 }
  53
  54 static struct property *dlpar_parse_cc_property(struct cc_workarea *ccwa)
  55 {
  56         struct property *prop;
  57         char *name;
  58         char *value;
  59
  60         prop = kzalloc(sizeof(*prop), GFP_KERNEL);
  61         if (!prop)
  62                 return NULL;
  63
  64         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
  65         prop->name = kstrdup(name, GFP_KERNEL);
  66
  67         prop->length = be32_to_cpu(ccwa->prop_length);
  68         value = (char *)ccwa + be32_to_cpu(ccwa->prop_offset);
  69         prop->value = kmemdup(value, prop->length, GFP_KERNEL);
  70         if (!prop->value) {
  71                 dlpar_free_cc_property(prop);
  72                 return NULL;
  73         }
  74
  75         return prop;
  76 }
  77
  78 static struct device_node *dlpar_parse_cc_node(struct cc_workarea *ccwa,
  79                                                const char *path)
  80 {
  81         struct device_node *dn;
  82         char *name;
  83
  84         /* If parent node path is "/" advance path to NULL terminator to
  85          * prevent double leading slashs in full_name.
  86          */
  87         if (!path[1])
  88                 path++;
  89
  90         dn = kzalloc(sizeof(*dn), GFP_KERNEL);
  91         if (!dn)
  92                 return NULL;
  93
  94         name = (char *)ccwa + be32_to_cpu(ccwa->name_offset);
  95         dn->full_name = kasprintf(GFP_KERNEL, "%s/%s", path, name);
  96         if (!dn->full_name) {
  97                 kfree(dn);
  98                 return NULL;
  99         }
 100
 101         of_node_set_flag(dn, OF_DYNAMIC);
 102         of_node_init(dn);
 103
 104         return dn;
 105 }
 106
 107 static void dlpar_free_one_cc_node(struct device_node *dn)
 108 {
 109         struct property *prop;
 110
 111         while (dn->properties) {
 112                 prop = dn->properties;
 113                 dn->properties = prop->next;
 114                 dlpar_free_cc_property(prop);
 115         }
 116
 117         kfree(dn->full_name);
 118         kfree(dn);
 119 }
 120
 121 void dlpar_free_cc_nodes(struct device_node *dn)
 122 {
 123         if (dn->child)
 124                 dlpar_free_cc_nodes(dn->child);
 125
 126         if (dn->sibling)
 127                 dlpar_free_cc_nodes(dn->sibling);
 128
 129         dlpar_free_one_cc_node(dn);
 130 }
 131
 132 #define COMPLETE        0
 133 #define NEXT_SIBLING    1
 134 #define NEXT_CHILD      2
 135 #define NEXT_PROPERTY   3
 136 #define PREV_PARENT     4
 137 #define MORE_MEMORY     5
 138 #define CALL_AGAIN      -2
 139 #define ERR_CFG_USE     -9003
 140
 141 struct device_node *dlpar_configure_connector(__be32 drc_index,
 142                                               struct device_node *parent)
 143 {
 144         struct device_node *dn;
 145         struct device_node *first_dn = NULL;
 146         struct device_node *last_dn = NULL;
 147         struct property *property;
 148         struct property *last_property = NULL;
 149         struct cc_workarea *ccwa;
 150         char *data_buf;
 151         const char *parent_path = parent->full_name;
 152         int cc_token;
 153         int rc = -1;
 154
 155         cc_token = rtas_token("ibm,configure-connector");
 156         if (cc_token == RTAS_UNKNOWN_SERVICE)
 157                 return NULL;
 158
 159         data_buf = kzalloc(RTAS_DATA_BUF_SIZE, GFP_KERNEL);
 160         if (!data_buf)
 161                 return NULL;
 162
 163         ccwa = (struct cc_workarea *)&data_buf[0];
 164         ccwa->drc_index = drc_index;
 165         ccwa->zero = 0;
 166
 167         do {
 168                 /* Since we release the rtas_data_buf lock between configure
 169                  * connector calls we want to re-populate the rtas_data_buffer
 170                  * with the contents of the previous call.
 171                  */
 172                 spin_lock(&rtas_data_buf_lock);
 173
 174                 memcpy(rtas_data_buf, data_buf, RTAS_DATA_BUF_SIZE);
 175                 rc = rtas_call(cc_token, 2, 1, NULL, rtas_data_buf, NULL);
 176                 memcpy(data_buf, rtas_data_buf, RTAS_DATA_BUF_SIZE);
 177
 178                 spin_unlock(&rtas_data_buf_lock);
 179
 180                 switch (rc) {
 181                 case COMPLETE:
 182                         break;
 183
 184                 case NEXT_SIBLING:
 185                         dn = dlpar_parse_cc_node(ccwa, parent_path);
 186                         if (!dn)
 187                                 goto cc_error;
 188
 189                         dn->parent = last_dn->parent;
 190                         last_dn->sibling = dn;
 191                         last_dn = dn;
 192                         break;
 193
 194                 case NEXT_CHILD:
 195                         if (first_dn)
 196                                 parent_path = last_dn->full_name;
 197
 198                         dn = dlpar_parse_cc_node(ccwa, parent_path);
 199                         if (!dn)
 200                                 goto cc_error;
 201
 202                         if (!first_dn) {
 203                                 dn->parent = parent;
 204                                 first_dn = dn;
 205                         } else {
 206                                 dn->parent = last_dn;
 207                                 if (last_dn)
 208                                         last_dn->child = dn;
 209                         }
 210
 211                         last_dn = dn;
 212                         break;
 213
 214                 case NEXT_PROPERTY:
 215                         property = dlpar_parse_cc_property(ccwa);
 216                         if (!property)
 217                                 goto cc_error;
 218
 219                         if (!last_dn->properties)
 220                                 last_dn->properties = property;
 221                         else
 222                                 last_property->next = property;
 223
 224                         last_property = property;
 225                         break;
 226
 227                 case PREV_PARENT:
 228                         last_dn = last_dn->parent;
 229                         parent_path = last_dn->parent->full_name;
 230                         break;
 231
 232                 case CALL_AGAIN:
 233                         break;
 234
 235                 case MORE_MEMORY:
 236                 case ERR_CFG_USE:
 237                 default:
 238                         printk(KERN_ERR "Unexpected Error (%d) "
 239                                "returned from configure-connector\n", rc);
 240                         goto cc_error;
 241                 }
 242         } while (rc);
 243
 244 cc_error:
 245         kfree(data_buf);
 246
 247         if (rc) {
 248                 if (first_dn)
 249                         dlpar_free_cc_nodes(first_dn);
 250
 251                 return NULL;
 252         }
 253
 254         return first_dn;
 255 }
 256
 257 int dlpar_attach_node(struct device_node *dn)
 258 {
 259         int rc;
 260
 261         dn->parent = pseries_of_derive_parent(dn->full_name);
 262         if (IS_ERR(dn->parent))
 263                 return PTR_ERR(dn->parent);
 264
 265         rc = of_attach_node(dn);
 266         if (rc) {
 267                 printk(KERN_ERR "Failed to add device node %s\n",
 268                        dn->full_name);
 269                 return rc;
 270         }
 271
 272         of_node_put(dn->parent);
 273         return 0;
 274 }
 275
 276 int dlpar_detach_node(struct device_node *dn)
 277 {
 278         struct device_node *child;
 279         int rc;
 280
 281         child = of_get_next_child(dn, NULL);
 282         while (child) {
 283                 dlpar_detach_node(child);
 284                 child = of_get_next_child(dn, child);
 285         }
 286
 287         rc = of_detach_node(dn);
 288         if (rc)
 289                 return rc;
 290
 291         of_node_put(dn); /* Must decrement the refcount */
 292         return 0;
 293 }
 294
 295 #define DR_ENTITY_SENSE         9003
 296 #define DR_ENTITY_PRESENT       1
 297 #define DR_ENTITY_UNUSABLE      2
 298 #define ALLOCATION_STATE        9003
 299 #define ALLOC_UNUSABLE          0
 300 #define ALLOC_USABLE            1
 301 #define ISOLATION_STATE         9001
 302 #define ISOLATE                 0
 303 #define UNISOLATE               1
 304
 305 int dlpar_acquire_drc(u32 drc_index)
 306 {
 307         int dr_status, rc;
 308
 309         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
 310                        DR_ENTITY_SENSE, drc_index);
 311         if (rc || dr_status != DR_ENTITY_UNUSABLE)
 312                 return -1;
 313
 314         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_USABLE);
 315         if (rc)
 316                 return rc;
 317
 318         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
 319         if (rc) {
 320                 rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
 321                 return rc;
 322         }
 323
 324         return 0;
 325 }
 326
 327 int dlpar_release_drc(u32 drc_index)
 328 {
 329         int dr_status, rc;
 330
 331         rc = rtas_call(rtas_token("get-sensor-state"), 2, 2, &dr_status,
 332                        DR_ENTITY_SENSE, drc_index);
 333         if (rc || dr_status != DR_ENTITY_PRESENT)
 334                 return -1;
 335
 336         rc = rtas_set_indicator(ISOLATION_STATE, drc_index, ISOLATE);
 337         if (rc)
 338                 return rc;
 339
 340         rc = rtas_set_indicator(ALLOCATION_STATE, drc_index, ALLOC_UNUSABLE);
 341         if (rc) {
 342                 rtas_set_indicator(ISOLATION_STATE, drc_index, UNISOLATE);
 343                 return rc;
 344         }
 345
 346         return 0;
 347 }
 348
 349 static int handle_dlpar_errorlog(struct pseries_hp_errorlog *hp_elog)
 350 {
 351         int rc;
 352
 353         /* pseries error logs are in BE format, convert to cpu type */
 354         switch (hp_elog->id_type) {
 355         case PSERIES_HP_ELOG_ID_DRC_COUNT:
 356                 hp_elog->_drc_u.drc_count =
 357                                         be32_to_cpu(hp_elog->_drc_u.drc_count);
 358                 break;
 359         case PSERIES_HP_ELOG_ID_DRC_INDEX:
 360                 hp_elog->_drc_u.drc_index =
 361                                         be32_to_cpu(hp_elog->_drc_u.drc_index);
 362         }
 363
 364         switch (hp_elog->resource) {
 365         case PSERIES_HP_ELOG_RESOURCE_MEM:
 366                 rc = dlpar_memory(hp_elog);
 367                 break;
 368         case PSERIES_HP_ELOG_RESOURCE_CPU:
 369                 rc = dlpar_cpu(hp_elog);
 370                 break;
 371         default:
 372                 pr_warn_ratelimited("Invalid resource (%d) specified\n",
 373                                     hp_elog->resource);
 374                 rc = -EINVAL;
 375         }
 376
 377         return rc;
 378 }
 379
 380 static void pseries_hp_work_fn(struct work_struct *work)
 381 {
 382         struct pseries_hp_work *hp_work =
 383                         container_of(work, struct pseries_hp_work, work);
 384
 385         if (hp_work->rc)
 386                 *(hp_work->rc) = handle_dlpar_errorlog(hp_work->errlog);
 387         else
 388                 handle_dlpar_errorlog(hp_work->errlog);
 389
 390         if (hp_work->hp_completion)
 391                 complete(hp_work->hp_completion);
 392
 393         kfree(hp_work->errlog);
 394         kfree((void *)work);
 395 }
 396
 397 void queue_hotplug_event(struct pseries_hp_errorlog *hp_errlog,
 398                          struct completion *hotplug_done, int *rc)
 399 {
 400         struct pseries_hp_work *work;
 401         struct pseries_hp_errorlog *hp_errlog_copy;
 402
 403         hp_errlog_copy = kmalloc(sizeof(struct pseries_hp_errorlog),
 404                                  GFP_KERNEL);
 405         memcpy(hp_errlog_copy, hp_errlog, sizeof(struct pseries_hp_errorlog));
 406
 407         work = kmalloc(sizeof(struct pseries_hp_work), GFP_KERNEL);
 408         if (work) {
 409                 INIT_WORK((struct work_struct *)work, pseries_hp_work_fn);
 410                 work->errlog = hp_errlog_copy;
 411                 work->hp_completion = hotplug_done;
 412                 work->rc = rc;
 413                 queue_work(pseries_hp_wq, (struct work_struct *)work);
 414         } else {
 415                 *rc = -ENOMEM;
 416                 kfree(hp_errlog_copy);
 417                 complete(hotplug_done);
 418         }
 419 }
 420
 421 static int dlpar_parse_resource(char **cmd, struct pseries_hp_errorlog *hp_elog)
 422 {
 423         char *arg;
 424
 425         arg = strsep(cmd, " ");
 426         if (!arg)
 427                 return -EINVAL;
 428
 429         if (sysfs_streq(arg, "memory")) {
 430                 hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_MEM;
 431         } else if (sysfs_streq(arg, "cpu")) {
 432                 hp_elog->resource = PSERIES_HP_ELOG_RESOURCE_CPU;
 433         } else {
 434                 pr_err("Invalid resource specified.\n");
 435                 return -EINVAL;
 436         }
 437
 438         return 0;
 439 }
 440
 441 static int dlpar_parse_action(char **cmd, struct pseries_hp_errorlog *hp_elog)
 442 {
 443         char *arg;
 444
 445         arg = strsep(cmd, " ");
 446         if (!arg)
 447                 return -EINVAL;
 448
 449         if (sysfs_streq(arg, "add")) {
 450                 hp_elog->action = PSERIES_HP_ELOG_ACTION_ADD;
 451         } else if (sysfs_streq(arg, "remove")) {
 452                 hp_elog->action = PSERIES_HP_ELOG_ACTION_REMOVE;
 453         } else {
 454                 pr_err("Invalid action specified.\n");
 455                 return -EINVAL;
 456         }
 457
 458         return 0;
 459 }
 460
 461 static int dlpar_parse_id_type(char **cmd, struct pseries_hp_errorlog *hp_elog)
 462 {
 463         char *arg;
 464         u32 count, index;
 465
 466         arg = strsep(cmd, " ");
 467         if (!arg)
 468                 return -EINVAL;
 469
 470         if (sysfs_streq(arg, "index")) {
 471                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_INDEX;
 472                 arg = strsep(cmd, " ");
 473                 if (!arg) {
 474                         pr_err("No DRC Index specified.\n");
 475                         return -EINVAL;
 476                 }
 477
 478                 if (kstrtou32(arg, 0, &index)) {
 479                         pr_err("Invalid DRC Index specified.\n");
 480                         return -EINVAL;
 481                 }
 482
 483                 hp_elog->_drc_u.drc_index = cpu_to_be32(index);
 484         } else if (sysfs_streq(arg, "count")) {
 485                 hp_elog->id_type = PSERIES_HP_ELOG_ID_DRC_COUNT;
 486                 arg = strsep(cmd, " ");
 487                 if (!arg) {
 488                         pr_err("No DRC count specified.\n");
 489                         return -EINVAL;
 490                 }
 491
 492                 if (kstrtou32(arg, 0, &count)) {
 493                         pr_err("Invalid DRC count specified.\n");
 494                         return -EINVAL;
 495                 }
 496
 497                 hp_elog->_drc_u.drc_count = cpu_to_be32(count);
 498         } else {
 499                 pr_err("Invalid id_type specified.\n");
 500                 return -EINVAL;
 501         }
 502
 503         return 0;
 504 }
 505
 506 static ssize_t dlpar_store(struct class *class, struct class_attribute *attr,
 507                            const char *buf, size_t count)
 508 {
 509         struct pseries_hp_errorlog *hp_elog;
 510         struct completion hotplug_done;
 511         char *argbuf;
 512         char *args;
 513         int rc;
 514
 515         args = argbuf = kstrdup(buf, GFP_KERNEL);
 516         hp_elog = kzalloc(sizeof(*hp_elog), GFP_KERNEL);
 517         if (!hp_elog || !argbuf) {
 518                 pr_info("Could not allocate resources for DLPAR operation\n");
 519                 kfree(argbuf);
 520                 kfree(hp_elog);
 521                 return -ENOMEM;
 522         }
 523
 524         /*
 525          * Parse out the request from the user, this will be in the form:
 526          * <resource> <action> <id_type> <id>
 527          */
 528         rc = dlpar_parse_resource(&args, hp_elog);
 529         if (rc)
 530                 goto dlpar_store_out;
 531
 532         rc = dlpar_parse_action(&args, hp_elog);
 533         if (rc)
 534                 goto dlpar_store_out;
 535
 536         rc = dlpar_parse_id_type(&args, hp_elog);
 537         if (rc)
 538                 goto dlpar_store_out;
 539
 540         init_completion(&hotplug_done);
 541         queue_hotplug_event(hp_elog, &hotplug_done, &rc);
 542         wait_for_completion(&hotplug_done);
 543
 544 dlpar_store_out:
 545         kfree(argbuf);
 546         kfree(hp_elog);
 547
 548         if (rc)
 549                 pr_err("Could not handle DLPAR request \"%s\"\n", buf);
 550
 551         return rc ? rc : count;
 552 }
 553
 554 static CLASS_ATTR(dlpar, S_IWUSR, NULL, dlpar_store);
 555
 556 static int __init pseries_dlpar_init(void)
 557 {
 558         pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
 559                                         WQ_UNBOUND, 1);
 560         return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
 561 }
 562 machine_device_initcall(pseries, pseries_dlpar_init);
 563