arch/powerpc/platforms/pseries/hotplug-memory.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * pseries Memory Hotplug infrastructure.
   4  *
   5  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
   6  */
   7
   8 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
   9
  10 #include <linux/of.h>
  11 #include <linux/of_address.h>
  12 #include <linux/memblock.h>
  13 #include <linux/memory.h>
  14 #include <linux/memory_hotplug.h>
  15 #include <linux/slab.h>
  16
  17 #include <asm/firmware.h>
  18 #include <asm/machdep.h>
  19 #include <asm/prom.h>
  20 #include <asm/sparsemem.h>
  21 #include <asm/fadump.h>
  22 #include <asm/drmem.h>
  23 #include "pseries.h"
  24
  25 unsigned long pseries_memory_block_size(void)
  26 {
  27         struct device_node *np;
  28         u64 memblock_size = MIN_MEMORY_BLOCK_SIZE;
  29         struct resource r;
  30
  31         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
  32         if (np) {
  33                 int len;
  34                 int size_cells;
  35                 const __be32 *prop;
  36
  37                 size_cells = of_n_size_cells(np);
  38
  39                 prop = of_get_property(np, "ibm,lmb-size", &len);
  40                 if (prop && len >= size_cells * sizeof(__be32))
  41                         memblock_size = of_read_number(prop, size_cells);
  42                 of_node_put(np);
  43
  44         } else  if (machine_is(pseries)) {
  45                 /* This fallback really only applies to pseries */
  46                 unsigned int memzero_size = 0;
  47
  48                 np = of_find_node_by_path("/memory@0");
  49                 if (np) {
  50                         if (!of_address_to_resource(np, 0, &r))
  51                                 memzero_size = resource_size(&r);
  52                         of_node_put(np);
  53                 }
  54
  55                 if (memzero_size) {
  56                         /* We now know the size of memory@0, use this to find
  57                          * the first memoryblock and get its size.
  58                          */
  59                         char buf[64];
  60
  61                         sprintf(buf, "/memory@%x", memzero_size);
  62                         np = of_find_node_by_path(buf);
  63                         if (np) {
  64                                 if (!of_address_to_resource(np, 0, &r))
  65                                         memblock_size = resource_size(&r);
  66                                 of_node_put(np);
  67                         }
  68                 }
  69         }
  70         return memblock_size;
  71 }
  72
  73 static void dlpar_free_property(struct property *prop)
  74 {
  75         kfree(prop->name);
  76         kfree(prop->value);
  77         kfree(prop);
  78 }
  79
  80 static struct property *dlpar_clone_property(struct property *prop,
  81                                              u32 prop_size)
  82 {
  83         struct property *new_prop;
  84
  85         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
  86         if (!new_prop)
  87                 return NULL;
  88
  89         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
  90         new_prop->value = kzalloc(prop_size, GFP_KERNEL);
  91         if (!new_prop->name || !new_prop->value) {
  92                 dlpar_free_property(new_prop);
  93                 return NULL;
  94         }
  95
  96         memcpy(new_prop->value, prop->value, prop->length);
  97         new_prop->length = prop_size;
  98
  99         of_property_set_flag(new_prop, OF_DYNAMIC);
 100         return new_prop;
 101 }
 102
 103 static bool find_aa_index(struct device_node *dr_node,
 104                          struct property *ala_prop,
 105                          const u32 *lmb_assoc, u32 *aa_index)
 106 {
 107         u32 *assoc_arrays, new_prop_size;
 108         struct property *new_prop;
 109         int aa_arrays, aa_array_entries, aa_array_sz;
 110         int i, index;
 111
 112         /*
 113          * The ibm,associativity-lookup-arrays property is defined to be
 114          * a 32-bit value specifying the number of associativity arrays
 115          * followed by a 32-bitvalue specifying the number of entries per
 116          * array, followed by the associativity arrays.
 117          */
 118         assoc_arrays = ala_prop->value;
 119
 120         aa_arrays = be32_to_cpu(assoc_arrays[0]);
 121         aa_array_entries = be32_to_cpu(assoc_arrays[1]);
 122         aa_array_sz = aa_array_entries * sizeof(u32);
 123
 124         for (i = 0; i < aa_arrays; i++) {
 125                 index = (i * aa_array_entries) + 2;
 126
 127                 if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
 128                         continue;
 129
 130                 *aa_index = i;
 131                 return true;
 132         }
 133
 134         new_prop_size = ala_prop->length + aa_array_sz;
 135         new_prop = dlpar_clone_property(ala_prop, new_prop_size);
 136         if (!new_prop)
 137                 return false;
 138
 139         assoc_arrays = new_prop->value;
 140
 141         /* increment the number of entries in the lookup array */
 142         assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);
 143
 144         /* copy the new associativity into the lookup array */
 145         index = aa_arrays * aa_array_entries + 2;
 146         memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);
 147
 148         of_update_property(dr_node, new_prop);
 149
 150         /*
 151          * The associativity lookup array index for this lmb is
 152          * number of entries - 1 since we added its associativity
 153          * to the end of the lookup array.
 154          */
 155         *aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
 156         return true;
 157 }
 158
 159 static int update_lmb_associativity_index(struct drmem_lmb *lmb)
 160 {
 161         struct device_node *parent, *lmb_node, *dr_node;
 162         struct property *ala_prop;
 163         const u32 *lmb_assoc;
 164         u32 aa_index;
 165         bool found;
 166
 167         parent = of_find_node_by_path("/");
 168         if (!parent)
 169                 return -ENODEV;
 170
 171         lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
 172                                              parent);
 173         of_node_put(parent);
 174         if (!lmb_node)
 175                 return -EINVAL;
 176
 177         lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
 178         if (!lmb_assoc) {
 179                 dlpar_free_cc_nodes(lmb_node);
 180                 return -ENODEV;
 181         }
 182
 183         update_numa_distance(lmb_node);
 184
 185         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 186         if (!dr_node) {
 187                 dlpar_free_cc_nodes(lmb_node);
 188                 return -ENODEV;
 189         }
 190
 191         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
 192                                     NULL);
 193         if (!ala_prop) {
 194                 of_node_put(dr_node);
 195                 dlpar_free_cc_nodes(lmb_node);
 196                 return -ENODEV;
 197         }
 198
 199         found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);
 200
 201         of_node_put(dr_node);
 202         dlpar_free_cc_nodes(lmb_node);
 203
 204         if (!found) {
 205                 pr_err("Could not find LMB associativity\n");
 206                 return -1;
 207         }
 208
 209         lmb->aa_index = aa_index;
 210         return 0;
 211 }
 212
 213 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 214 {
 215         unsigned long section_nr;
 216         struct memory_block *mem_block;
 217
 218         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 219
 220         mem_block = find_memory_block(section_nr);
 221         return mem_block;
 222 }
 223
 224 static int get_lmb_range(u32 drc_index, int n_lmbs,
 225                          struct drmem_lmb **start_lmb,
 226                          struct drmem_lmb **end_lmb)
 227 {
 228         struct drmem_lmb *lmb, *start, *end;
 229         struct drmem_lmb *limit;
 230
 231         start = NULL;
 232         for_each_drmem_lmb(lmb) {
 233                 if (lmb->drc_index == drc_index) {
 234                         start = lmb;
 235                         break;
 236                 }
 237         }
 238
 239         if (!start)
 240                 return -EINVAL;
 241
 242         end = &start[n_lmbs];
 243
 244         limit = &drmem_info->lmbs[drmem_info->n_lmbs];
 245         if (end > limit)
 246                 return -EINVAL;
 247
 248         *start_lmb = start;
 249         *end_lmb = end;
 250         return 0;
 251 }
 252
 253 static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
 254 {
 255         struct memory_block *mem_block;
 256         int rc;
 257
 258         mem_block = lmb_to_memblock(lmb);
 259         if (!mem_block)
 260                 return -EINVAL;
 261
 262         if (online && mem_block->dev.offline)
 263                 rc = device_online(&mem_block->dev);
 264         else if (!online && !mem_block->dev.offline)
 265                 rc = device_offline(&mem_block->dev);
 266         else
 267                 rc = 0;
 268
 269         put_device(&mem_block->dev);
 270
 271         return rc;
 272 }
 273
 274 static int dlpar_online_lmb(struct drmem_lmb *lmb)
 275 {
 276         return dlpar_change_lmb_state(lmb, true);
 277 }
 278
 279 #ifdef CONFIG_MEMORY_HOTREMOVE
 280 static int dlpar_offline_lmb(struct drmem_lmb *lmb)
 281 {
 282         return dlpar_change_lmb_state(lmb, false);
 283 }
 284
 285 static int pseries_remove_memblock(unsigned long base, unsigned long memblock_size)
 286 {
 287         unsigned long block_sz, start_pfn;
 288         int sections_per_block;
 289         int i;
 290
 291         start_pfn = base >> PAGE_SHIFT;
 292
 293         lock_device_hotplug();
 294
 295         if (!pfn_valid(start_pfn))
 296                 goto out;
 297
 298         block_sz = pseries_memory_block_size();
 299         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 300
 301         for (i = 0; i < sections_per_block; i++) {
 302                 __remove_memory(base, MIN_MEMORY_BLOCK_SIZE);
 303                 base += MIN_MEMORY_BLOCK_SIZE;
 304         }
 305
 306 out:
 307         /* Update memory regions for memory remove */
 308         memblock_remove(base, memblock_size);
 309         unlock_device_hotplug();
 310         return 0;
 311 }
 312
 313 static int pseries_remove_mem_node(struct device_node *np)
 314 {
 315         const __be32 *prop;
 316         unsigned long base;
 317         unsigned long lmb_size;
 318         int ret = -EINVAL;
 319         int addr_cells, size_cells;
 320
 321         /*
 322          * Check to see if we are actually removing memory
 323          */
 324         if (!of_node_is_type(np, "memory"))
 325                 return 0;
 326
 327         /*
 328          * Find the base address and size of the memblock
 329          */
 330         prop = of_get_property(np, "reg", NULL);
 331         if (!prop)
 332                 return ret;
 333
 334         addr_cells = of_n_addr_cells(np);
 335         size_cells = of_n_size_cells(np);
 336
 337         /*
 338          * "reg" property represents (addr,size) tuple.
 339          */
 340         base = of_read_number(prop, addr_cells);
 341         prop += addr_cells;
 342         lmb_size = of_read_number(prop, size_cells);
 343
 344         pseries_remove_memblock(base, lmb_size);
 345         return 0;
 346 }
 347
 348 static bool lmb_is_removable(struct drmem_lmb *lmb)
 349 {
 350         if ((lmb->flags & DRCONF_MEM_RESERVED) ||
 351                 !(lmb->flags & DRCONF_MEM_ASSIGNED))
 352                 return false;
 353
 354 #ifdef CONFIG_FA_DUMP
 355         /*
 356          * Don't hot-remove memory that falls in fadump boot memory area
 357          * and memory that is reserved for capturing old kernel memory.
 358          */
 359         if (is_fadump_memory_area(lmb->base_addr, memory_block_size_bytes()))
 360                 return false;
 361 #endif
 362         /* device_offline() will determine if we can actually remove this lmb */
 363         return true;
 364 }
 365
 366 static int dlpar_add_lmb(struct drmem_lmb *);
 367
 368 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 369 {
 370         struct memory_block *mem_block;
 371         unsigned long block_sz;
 372         int rc;
 373
 374         if (!lmb_is_removable(lmb))
 375                 return -EINVAL;
 376
 377         mem_block = lmb_to_memblock(lmb);
 378         if (mem_block == NULL)
 379                 return -EINVAL;
 380
 381         rc = dlpar_offline_lmb(lmb);
 382         if (rc) {
 383                 put_device(&mem_block->dev);
 384                 return rc;
 385         }
 386
 387         block_sz = pseries_memory_block_size();
 388
 389         __remove_memory(lmb->base_addr, block_sz);
 390         put_device(&mem_block->dev);
 391
 392         /* Update memory regions for memory remove */
 393         memblock_remove(lmb->base_addr, block_sz);
 394
 395         invalidate_lmb_associativity_index(lmb);
 396         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 397
 398         return 0;
 399 }
 400
 401 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 402 {
 403         struct drmem_lmb *lmb;
 404         int lmbs_reserved = 0;
 405         int lmbs_available = 0;
 406         int rc;
 407
 408         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 409
 410         if (lmbs_to_remove == 0)
 411                 return -EINVAL;
 412
 413         /* Validate that there are enough LMBs to satisfy the request */
 414         for_each_drmem_lmb(lmb) {
 415                 if (lmb_is_removable(lmb))
 416                         lmbs_available++;
 417
 418                 if (lmbs_available == lmbs_to_remove)
 419                         break;
 420         }
 421
 422         if (lmbs_available < lmbs_to_remove) {
 423                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 424                         lmbs_available, lmbs_to_remove);
 425                 return -EINVAL;
 426         }
 427
 428         for_each_drmem_lmb(lmb) {
 429                 rc = dlpar_remove_lmb(lmb);
 430                 if (rc)
 431                         continue;
 432
 433                 /* Mark this lmb so we can add it later if all of the
 434                  * requested LMBs cannot be removed.
 435                  */
 436                 drmem_mark_lmb_reserved(lmb);
 437
 438                 lmbs_reserved++;
 439                 if (lmbs_reserved == lmbs_to_remove)
 440                         break;
 441         }
 442
 443         if (lmbs_reserved != lmbs_to_remove) {
 444                 pr_err("Memory hot-remove failed, adding LMB's back\n");
 445
 446                 for_each_drmem_lmb(lmb) {
 447                         if (!drmem_lmb_reserved(lmb))
 448                                 continue;
 449
 450                         rc = dlpar_add_lmb(lmb);
 451                         if (rc)
 452                                 pr_err("Failed to add LMB back, drc index %x\n",
 453                                        lmb->drc_index);
 454
 455                         drmem_remove_lmb_reservation(lmb);
 456
 457                         lmbs_reserved--;
 458                         if (lmbs_reserved == 0)
 459                                 break;
 460                 }
 461
 462                 rc = -EINVAL;
 463         } else {
 464                 for_each_drmem_lmb(lmb) {
 465                         if (!drmem_lmb_reserved(lmb))
 466                                 continue;
 467
 468                         dlpar_release_drc(lmb->drc_index);
 469                         pr_info("Memory at %llx was hot-removed\n",
 470                                 lmb->base_addr);
 471
 472                         drmem_remove_lmb_reservation(lmb);
 473
 474                         lmbs_reserved--;
 475                         if (lmbs_reserved == 0)
 476                                 break;
 477                 }
 478                 rc = 0;
 479         }
 480
 481         return rc;
 482 }
 483
 484 static int dlpar_memory_remove_by_index(u32 drc_index)
 485 {
 486         struct drmem_lmb *lmb;
 487         int lmb_found;
 488         int rc;
 489
 490         pr_debug("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 491
 492         lmb_found = 0;
 493         for_each_drmem_lmb(lmb) {
 494                 if (lmb->drc_index == drc_index) {
 495                         lmb_found = 1;
 496                         rc = dlpar_remove_lmb(lmb);
 497                         if (!rc)
 498                                 dlpar_release_drc(lmb->drc_index);
 499
 500                         break;
 501                 }
 502         }
 503
 504         if (!lmb_found)
 505                 rc = -EINVAL;
 506
 507         if (rc)
 508                 pr_debug("Failed to hot-remove memory at %llx\n",
 509                          lmb->base_addr);
 510         else
 511                 pr_debug("Memory at %llx was hot-removed\n", lmb->base_addr);
 512
 513         return rc;
 514 }
 515
 516 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 517 {
 518         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 519         int rc;
 520
 521         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 522                 lmbs_to_remove, drc_index);
 523
 524         if (lmbs_to_remove == 0)
 525                 return -EINVAL;
 526
 527         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 528         if (rc)
 529                 return -EINVAL;
 530
 531         /*
 532          * Validate that all LMBs in range are not reserved. Note that it
 533          * is ok if they are !ASSIGNED since our goal here is to remove the
 534          * LMB range, regardless of whether some LMBs were already removed
 535          * by any other reason.
 536          *
 537          * This is a contrast to what is done in remove_by_count() where we
 538          * check for both RESERVED and !ASSIGNED (via lmb_is_removable()),
 539          * because we want to remove a fixed amount of LMBs in that function.
 540          */
 541         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 542                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 543                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 544                                 lmb->base_addr, lmb->drc_index);
 545                         return -EINVAL;
 546                 }
 547         }
 548
 549         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 550                 /*
 551                  * dlpar_remove_lmb() will error out if the LMB is already
 552                  * !ASSIGNED, but this case is a no-op for us.
 553                  */
 554                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 555                         continue;
 556
 557                 rc = dlpar_remove_lmb(lmb);
 558                 if (rc)
 559                         break;
 560
 561                 drmem_mark_lmb_reserved(lmb);
 562         }
 563
 564         if (rc) {
 565                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 566
 567
 568                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 569                         if (!drmem_lmb_reserved(lmb))
 570                                 continue;
 571
 572                         /*
 573                          * Setting the isolation state of an UNISOLATED/CONFIGURED
 574                          * device to UNISOLATE is a no-op, but the hypervisor can
 575                          * use it as a hint that the LMB removal failed.
 576                          */
 577                         dlpar_unisolate_drc(lmb->drc_index);
 578
 579                         rc = dlpar_add_lmb(lmb);
 580                         if (rc)
 581                                 pr_err("Failed to add LMB, drc index %x\n",
 582                                        lmb->drc_index);
 583
 584                         drmem_remove_lmb_reservation(lmb);
 585                 }
 586                 rc = -EINVAL;
 587         } else {
 588                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 589                         if (!drmem_lmb_reserved(lmb))
 590                                 continue;
 591
 592                         dlpar_release_drc(lmb->drc_index);
 593                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 594                                 lmb->base_addr, lmb->drc_index);
 595
 596                         drmem_remove_lmb_reservation(lmb);
 597                 }
 598         }
 599
 600         return rc;
 601 }
 602
 603 #else
 604 static inline int pseries_remove_memblock(unsigned long base,
 605                                           unsigned long memblock_size)
 606 {
 607         return -EOPNOTSUPP;
 608 }
 609 static inline int pseries_remove_mem_node(struct device_node *np)
 610 {
 611         return 0;
 612 }
 613 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 614 {
 615         return -EOPNOTSUPP;
 616 }
 617 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 618 {
 619         return -EOPNOTSUPP;
 620 }
 621 static int dlpar_memory_remove_by_index(u32 drc_index)
 622 {
 623         return -EOPNOTSUPP;
 624 }
 625
 626 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 627 {
 628         return -EOPNOTSUPP;
 629 }
 630 #endif /* CONFIG_MEMORY_HOTREMOVE */
 631
 632 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 633 {
 634         unsigned long block_sz;
 635         int nid, rc;
 636
 637         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 638                 return -EINVAL;
 639
 640         rc = update_lmb_associativity_index(lmb);
 641         if (rc) {
 642                 dlpar_release_drc(lmb->drc_index);
 643                 return rc;
 644         }
 645
 646         block_sz = memory_block_size_bytes();
 647
 648         /* Find the node id for this LMB.  Fake one if necessary. */
 649         nid = of_drconf_to_nid_single(lmb);
 650         if (nid < 0 || !node_possible(nid))
 651                 nid = first_online_node;
 652
 653         /* Add the memory */
 654         rc = __add_memory(nid, lmb->base_addr, block_sz, MHP_NONE);
 655         if (rc) {
 656                 invalidate_lmb_associativity_index(lmb);
 657                 return rc;
 658         }
 659
 660         rc = dlpar_online_lmb(lmb);
 661         if (rc) {
 662                 __remove_memory(lmb->base_addr, block_sz);
 663                 invalidate_lmb_associativity_index(lmb);
 664         } else {
 665                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 666         }
 667
 668         return rc;
 669 }
 670
 671 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 672 {
 673         struct drmem_lmb *lmb;
 674         int lmbs_available = 0;
 675         int lmbs_reserved = 0;
 676         int rc;
 677
 678         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 679
 680         if (lmbs_to_add == 0)
 681                 return -EINVAL;
 682
 683         /* Validate that there are enough LMBs to satisfy the request */
 684         for_each_drmem_lmb(lmb) {
 685                 if (lmb->flags & DRCONF_MEM_RESERVED)
 686                         continue;
 687
 688                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 689                         lmbs_available++;
 690
 691                 if (lmbs_available == lmbs_to_add)
 692                         break;
 693         }
 694
 695         if (lmbs_available < lmbs_to_add)
 696                 return -EINVAL;
 697
 698         for_each_drmem_lmb(lmb) {
 699                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 700                         continue;
 701
 702                 rc = dlpar_acquire_drc(lmb->drc_index);
 703                 if (rc)
 704                         continue;
 705
 706                 rc = dlpar_add_lmb(lmb);
 707                 if (rc) {
 708                         dlpar_release_drc(lmb->drc_index);
 709                         continue;
 710                 }
 711
 712                 /* Mark this lmb so we can remove it later if all of the
 713                  * requested LMBs cannot be added.
 714                  */
 715                 drmem_mark_lmb_reserved(lmb);
 716                 lmbs_reserved++;
 717                 if (lmbs_reserved == lmbs_to_add)
 718                         break;
 719         }
 720
 721         if (lmbs_reserved != lmbs_to_add) {
 722                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 723
 724                 for_each_drmem_lmb(lmb) {
 725                         if (!drmem_lmb_reserved(lmb))
 726                                 continue;
 727
 728                         rc = dlpar_remove_lmb(lmb);
 729                         if (rc)
 730                                 pr_err("Failed to remove LMB, drc index %x\n",
 731                                        lmb->drc_index);
 732                         else
 733                                 dlpar_release_drc(lmb->drc_index);
 734
 735                         drmem_remove_lmb_reservation(lmb);
 736                         lmbs_reserved--;
 737
 738                         if (lmbs_reserved == 0)
 739                                 break;
 740                 }
 741                 rc = -EINVAL;
 742         } else {
 743                 for_each_drmem_lmb(lmb) {
 744                         if (!drmem_lmb_reserved(lmb))
 745                                 continue;
 746
 747                         pr_debug("Memory at %llx (drc index %x) was hot-added\n",
 748                                  lmb->base_addr, lmb->drc_index);
 749                         drmem_remove_lmb_reservation(lmb);
 750                         lmbs_reserved--;
 751
 752                         if (lmbs_reserved == 0)
 753                                 break;
 754                 }
 755                 rc = 0;
 756         }
 757
 758         return rc;
 759 }
 760
 761 static int dlpar_memory_add_by_index(u32 drc_index)
 762 {
 763         struct drmem_lmb *lmb;
 764         int rc, lmb_found;
 765
 766         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 767
 768         lmb_found = 0;
 769         for_each_drmem_lmb(lmb) {
 770                 if (lmb->drc_index == drc_index) {
 771                         lmb_found = 1;
 772                         rc = dlpar_acquire_drc(lmb->drc_index);
 773                         if (!rc) {
 774                                 rc = dlpar_add_lmb(lmb);
 775                                 if (rc)
 776                                         dlpar_release_drc(lmb->drc_index);
 777                         }
 778
 779                         break;
 780                 }
 781         }
 782
 783         if (!lmb_found)
 784                 rc = -EINVAL;
 785
 786         if (rc)
 787                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 788         else
 789                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 790                         lmb->base_addr, drc_index);
 791
 792         return rc;
 793 }
 794
 795 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 796 {
 797         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 798         int rc;
 799
 800         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 801                 lmbs_to_add, drc_index);
 802
 803         if (lmbs_to_add == 0)
 804                 return -EINVAL;
 805
 806         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 807         if (rc)
 808                 return -EINVAL;
 809
 810         /* Validate that the LMBs in this range are not reserved */
 811         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 812                 /* Fail immediately if the whole range can't be hot-added */
 813                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 814                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 815                                         lmb->base_addr, lmb->drc_index);
 816                         return -EINVAL;
 817                 }
 818         }
 819
 820         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 821                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 822                         continue;
 823
 824                 rc = dlpar_acquire_drc(lmb->drc_index);
 825                 if (rc)
 826                         break;
 827
 828                 rc = dlpar_add_lmb(lmb);
 829                 if (rc) {
 830                         dlpar_release_drc(lmb->drc_index);
 831                         break;
 832                 }
 833
 834                 drmem_mark_lmb_reserved(lmb);
 835         }
 836
 837         if (rc) {
 838                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 839
 840                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 841                         if (!drmem_lmb_reserved(lmb))
 842                                 continue;
 843
 844                         rc = dlpar_remove_lmb(lmb);
 845                         if (rc)
 846                                 pr_err("Failed to remove LMB, drc index %x\n",
 847                                        lmb->drc_index);
 848                         else
 849                                 dlpar_release_drc(lmb->drc_index);
 850
 851                         drmem_remove_lmb_reservation(lmb);
 852                 }
 853                 rc = -EINVAL;
 854         } else {
 855                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 856                         if (!drmem_lmb_reserved(lmb))
 857                                 continue;
 858
 859                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 860                                 lmb->base_addr, lmb->drc_index);
 861                         drmem_remove_lmb_reservation(lmb);
 862                 }
 863         }
 864
 865         return rc;
 866 }
 867
 868 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 869 {
 870         u32 count, drc_index;
 871         int rc;
 872
 873         lock_device_hotplug();
 874
 875         switch (hp_elog->action) {
 876         case PSERIES_HP_ELOG_ACTION_ADD:
 877                 switch (hp_elog->id_type) {
 878                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 879                         count = hp_elog->_drc_u.drc_count;
 880                         rc = dlpar_memory_add_by_count(count);
 881                         break;
 882                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 883                         drc_index = hp_elog->_drc_u.drc_index;
 884                         rc = dlpar_memory_add_by_index(drc_index);
 885                         break;
 886                 case PSERIES_HP_ELOG_ID_DRC_IC:
 887                         count = hp_elog->_drc_u.ic.count;
 888                         drc_index = hp_elog->_drc_u.ic.index;
 889                         rc = dlpar_memory_add_by_ic(count, drc_index);
 890                         break;
 891                 default:
 892                         rc = -EINVAL;
 893                         break;
 894                 }
 895
 896                 break;
 897         case PSERIES_HP_ELOG_ACTION_REMOVE:
 898                 switch (hp_elog->id_type) {
 899                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 900                         count = hp_elog->_drc_u.drc_count;
 901                         rc = dlpar_memory_remove_by_count(count);
 902                         break;
 903                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 904                         drc_index = hp_elog->_drc_u.drc_index;
 905                         rc = dlpar_memory_remove_by_index(drc_index);
 906                         break;
 907                 case PSERIES_HP_ELOG_ID_DRC_IC:
 908                         count = hp_elog->_drc_u.ic.count;
 909                         drc_index = hp_elog->_drc_u.ic.index;
 910                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 911                         break;
 912                 default:
 913                         rc = -EINVAL;
 914                         break;
 915                 }
 916
 917                 break;
 918         default:
 919                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 920                 rc = -EINVAL;
 921                 break;
 922         }
 923
 924         if (!rc)
 925                 rc = drmem_update_dt();
 926
 927         unlock_device_hotplug();
 928         return rc;
 929 }
 930
 931 static int pseries_add_mem_node(struct device_node *np)
 932 {
 933         const __be32 *prop;
 934         unsigned long base;
 935         unsigned long lmb_size;
 936         int ret = -EINVAL;
 937         int addr_cells, size_cells;
 938
 939         /*
 940          * Check to see if we are actually adding memory
 941          */
 942         if (!of_node_is_type(np, "memory"))
 943                 return 0;
 944
 945         /*
 946          * Find the base and size of the memblock
 947          */
 948         prop = of_get_property(np, "reg", NULL);
 949         if (!prop)
 950                 return ret;
 951
 952         addr_cells = of_n_addr_cells(np);
 953         size_cells = of_n_size_cells(np);
 954         /*
 955          * "reg" property represents (addr,size) tuple.
 956          */
 957         base = of_read_number(prop, addr_cells);
 958         prop += addr_cells;
 959         lmb_size = of_read_number(prop, size_cells);
 960
 961         /*
 962          * Update memory region to represent the memory add
 963          */
 964         ret = memblock_add(base, lmb_size);
 965         return (ret < 0) ? -EINVAL : 0;
 966 }
 967
 968 static int pseries_memory_notifier(struct notifier_block *nb,
 969                                    unsigned long action, void *data)
 970 {
 971         struct of_reconfig_data *rd = data;
 972         int err = 0;
 973
 974         switch (action) {
 975         case OF_RECONFIG_ATTACH_NODE:
 976                 err = pseries_add_mem_node(rd->dn);
 977                 break;
 978         case OF_RECONFIG_DETACH_NODE:
 979                 err = pseries_remove_mem_node(rd->dn);
 980                 break;
 981         case OF_RECONFIG_UPDATE_PROPERTY:
 982                 if (!strcmp(rd->dn->name,
 983                             "ibm,dynamic-reconfiguration-memory"))
 984                         drmem_update_lmbs(rd->prop);
 985         }
 986         return notifier_from_errno(err);
 987 }
 988
 989 static struct notifier_block pseries_mem_nb = {
 990         .notifier_call = pseries_memory_notifier,
 991 };
 992
 993 static int __init pseries_memory_hotplug_init(void)
 994 {
 995         if (firmware_has_feature(FW_FEATURE_LPAR))
 996                 of_reconfig_notifier_register(&pseries_mem_nb);
 997
 998         return 0;
 999 }
1000 machine_device_initcall(pseries, pseries_memory_hotplug_init);