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 mem_section *mem_sect;
 217         struct memory_block *mem_block;
 218
 219         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 220         mem_sect = __nr_to_section(section_nr);
 221
 222         mem_block = find_memory_block(mem_sect);
 223         return mem_block;
 224 }
 225
 226 static int get_lmb_range(u32 drc_index, int n_lmbs,
 227                          struct drmem_lmb **start_lmb,
 228                          struct drmem_lmb **end_lmb)
 229 {
 230         struct drmem_lmb *lmb, *start, *end;
 231         struct drmem_lmb *limit;
 232
 233         start = NULL;
 234         for_each_drmem_lmb(lmb) {
 235                 if (lmb->drc_index == drc_index) {
 236                         start = lmb;
 237                         break;
 238                 }
 239         }
 240
 241         if (!start)
 242                 return -EINVAL;
 243
 244         end = &start[n_lmbs];
 245
 246         limit = &drmem_info->lmbs[drmem_info->n_lmbs];
 247         if (end > limit)
 248                 return -EINVAL;
 249
 250         *start_lmb = start;
 251         *end_lmb = end;
 252         return 0;
 253 }
 254
 255 static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
 256 {
 257         struct memory_block *mem_block;
 258         int rc;
 259
 260         mem_block = lmb_to_memblock(lmb);
 261         if (!mem_block)
 262                 return -EINVAL;
 263
 264         if (online && mem_block->dev.offline)
 265                 rc = device_online(&mem_block->dev);
 266         else if (!online && !mem_block->dev.offline)
 267                 rc = device_offline(&mem_block->dev);
 268         else
 269                 rc = 0;
 270
 271         put_device(&mem_block->dev);
 272
 273         return rc;
 274 }
 275
 276 static int dlpar_online_lmb(struct drmem_lmb *lmb)
 277 {
 278         return dlpar_change_lmb_state(lmb, true);
 279 }
 280
 281 #ifdef CONFIG_MEMORY_HOTREMOVE
 282 static int dlpar_offline_lmb(struct drmem_lmb *lmb)
 283 {
 284         return dlpar_change_lmb_state(lmb, false);
 285 }
 286
 287 static int pseries_remove_memblock(unsigned long base, unsigned long memblock_size)
 288 {
 289         unsigned long block_sz, start_pfn;
 290         int sections_per_block;
 291         int i, nid;
 292
 293         start_pfn = base >> PAGE_SHIFT;
 294
 295         lock_device_hotplug();
 296
 297         if (!pfn_valid(start_pfn))
 298                 goto out;
 299
 300         block_sz = pseries_memory_block_size();
 301         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 302         nid = memory_add_physaddr_to_nid(base);
 303
 304         for (i = 0; i < sections_per_block; i++) {
 305                 __remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
 306                 base += MIN_MEMORY_BLOCK_SIZE;
 307         }
 308
 309 out:
 310         /* Update memory regions for memory remove */
 311         memblock_remove(base, memblock_size);
 312         unlock_device_hotplug();
 313         return 0;
 314 }
 315
 316 static int pseries_remove_mem_node(struct device_node *np)
 317 {
 318         const __be32 *prop;
 319         unsigned long base;
 320         unsigned long lmb_size;
 321         int ret = -EINVAL;
 322         int addr_cells, size_cells;
 323
 324         /*
 325          * Check to see if we are actually removing memory
 326          */
 327         if (!of_node_is_type(np, "memory"))
 328                 return 0;
 329
 330         /*
 331          * Find the base address and size of the memblock
 332          */
 333         prop = of_get_property(np, "reg", NULL);
 334         if (!prop)
 335                 return ret;
 336
 337         addr_cells = of_n_addr_cells(np);
 338         size_cells = of_n_size_cells(np);
 339
 340         /*
 341          * "reg" property represents (addr,size) tuple.
 342          */
 343         base = of_read_number(prop, addr_cells);
 344         prop += addr_cells;
 345         lmb_size = of_read_number(prop, size_cells);
 346
 347         pseries_remove_memblock(base, lmb_size);
 348         return 0;
 349 }
 350
 351 static bool lmb_is_removable(struct drmem_lmb *lmb)
 352 {
 353         if ((lmb->flags & DRCONF_MEM_RESERVED) ||
 354                 !(lmb->flags & DRCONF_MEM_ASSIGNED))
 355                 return false;
 356
 357 #ifdef CONFIG_FA_DUMP
 358         /*
 359          * Don't hot-remove memory that falls in fadump boot memory area
 360          * and memory that is reserved for capturing old kernel memory.
 361          */
 362         if (is_fadump_memory_area(lmb->base_addr, memory_block_size_bytes()))
 363                 return false;
 364 #endif
 365         /* device_offline() will determine if we can actually remove this lmb */
 366         return true;
 367 }
 368
 369 static int dlpar_add_lmb(struct drmem_lmb *);
 370
 371 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 372 {
 373         struct memory_block *mem_block;
 374         unsigned long block_sz;
 375         int rc;
 376
 377         if (!lmb_is_removable(lmb))
 378                 return -EINVAL;
 379
 380         mem_block = lmb_to_memblock(lmb);
 381         if (mem_block == NULL)
 382                 return -EINVAL;
 383
 384         rc = dlpar_offline_lmb(lmb);
 385         if (rc) {
 386                 put_device(&mem_block->dev);
 387                 return rc;
 388         }
 389
 390         block_sz = pseries_memory_block_size();
 391
 392         __remove_memory(mem_block->nid, lmb->base_addr, block_sz);
 393         put_device(&mem_block->dev);
 394
 395         /* Update memory regions for memory remove */
 396         memblock_remove(lmb->base_addr, block_sz);
 397
 398         invalidate_lmb_associativity_index(lmb);
 399         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 400
 401         return 0;
 402 }
 403
 404 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 405 {
 406         struct drmem_lmb *lmb;
 407         int lmbs_reserved = 0;
 408         int lmbs_available = 0;
 409         int rc;
 410
 411         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 412
 413         if (lmbs_to_remove == 0)
 414                 return -EINVAL;
 415
 416         /* Validate that there are enough LMBs to satisfy the request */
 417         for_each_drmem_lmb(lmb) {
 418                 if (lmb_is_removable(lmb))
 419                         lmbs_available++;
 420
 421                 if (lmbs_available == lmbs_to_remove)
 422                         break;
 423         }
 424
 425         if (lmbs_available < lmbs_to_remove) {
 426                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 427                         lmbs_available, lmbs_to_remove);
 428                 return -EINVAL;
 429         }
 430
 431         for_each_drmem_lmb(lmb) {
 432                 rc = dlpar_remove_lmb(lmb);
 433                 if (rc)
 434                         continue;
 435
 436                 /* Mark this lmb so we can add it later if all of the
 437                  * requested LMBs cannot be removed.
 438                  */
 439                 drmem_mark_lmb_reserved(lmb);
 440
 441                 lmbs_reserved++;
 442                 if (lmbs_reserved == lmbs_to_remove)
 443                         break;
 444         }
 445
 446         if (lmbs_reserved != lmbs_to_remove) {
 447                 pr_err("Memory hot-remove failed, adding LMB's back\n");
 448
 449                 for_each_drmem_lmb(lmb) {
 450                         if (!drmem_lmb_reserved(lmb))
 451                                 continue;
 452
 453                         rc = dlpar_add_lmb(lmb);
 454                         if (rc)
 455                                 pr_err("Failed to add LMB back, drc index %x\n",
 456                                        lmb->drc_index);
 457
 458                         drmem_remove_lmb_reservation(lmb);
 459
 460                         lmbs_reserved--;
 461                         if (lmbs_reserved == 0)
 462                                 break;
 463                 }
 464
 465                 rc = -EINVAL;
 466         } else {
 467                 for_each_drmem_lmb(lmb) {
 468                         if (!drmem_lmb_reserved(lmb))
 469                                 continue;
 470
 471                         dlpar_release_drc(lmb->drc_index);
 472                         pr_info("Memory at %llx was hot-removed\n",
 473                                 lmb->base_addr);
 474
 475                         drmem_remove_lmb_reservation(lmb);
 476
 477                         lmbs_reserved--;
 478                         if (lmbs_reserved == 0)
 479                                 break;
 480                 }
 481                 rc = 0;
 482         }
 483
 484         return rc;
 485 }
 486
 487 static int dlpar_memory_remove_by_index(u32 drc_index)
 488 {
 489         struct drmem_lmb *lmb;
 490         int lmb_found;
 491         int rc;
 492
 493         pr_debug("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 494
 495         lmb_found = 0;
 496         for_each_drmem_lmb(lmb) {
 497                 if (lmb->drc_index == drc_index) {
 498                         lmb_found = 1;
 499                         rc = dlpar_remove_lmb(lmb);
 500                         if (!rc)
 501                                 dlpar_release_drc(lmb->drc_index);
 502
 503                         break;
 504                 }
 505         }
 506
 507         if (!lmb_found)
 508                 rc = -EINVAL;
 509
 510         if (rc)
 511                 pr_debug("Failed to hot-remove memory at %llx\n",
 512                          lmb->base_addr);
 513         else
 514                 pr_debug("Memory at %llx was hot-removed\n", lmb->base_addr);
 515
 516         return rc;
 517 }
 518
 519 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 520 {
 521         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 522         int rc;
 523
 524         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 525                 lmbs_to_remove, drc_index);
 526
 527         if (lmbs_to_remove == 0)
 528                 return -EINVAL;
 529
 530         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 531         if (rc)
 532                 return -EINVAL;
 533
 534         /*
 535          * Validate that all LMBs in range are not reserved. Note that it
 536          * is ok if they are !ASSIGNED since our goal here is to remove the
 537          * LMB range, regardless of whether some LMBs were already removed
 538          * by any other reason.
 539          *
 540          * This is a contrast to what is done in remove_by_count() where we
 541          * check for both RESERVED and !ASSIGNED (via lmb_is_removable()),
 542          * because we want to remove a fixed amount of LMBs in that function.
 543          */
 544         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 545                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 546                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 547                                 lmb->base_addr, lmb->drc_index);
 548                         return -EINVAL;
 549                 }
 550         }
 551
 552         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 553                 /*
 554                  * dlpar_remove_lmb() will error out if the LMB is already
 555                  * !ASSIGNED, but this case is a no-op for us.
 556                  */
 557                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 558                         continue;
 559
 560                 rc = dlpar_remove_lmb(lmb);
 561                 if (rc)
 562                         break;
 563
 564                 drmem_mark_lmb_reserved(lmb);
 565         }
 566
 567         if (rc) {
 568                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 569
 570
 571                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 572                         if (!drmem_lmb_reserved(lmb))
 573                                 continue;
 574
 575                         /*
 576                          * Setting the isolation state of an UNISOLATED/CONFIGURED
 577                          * device to UNISOLATE is a no-op, but the hypervisor can
 578                          * use it as a hint that the LMB removal failed.
 579                          */
 580                         dlpar_unisolate_drc(lmb->drc_index);
 581
 582                         rc = dlpar_add_lmb(lmb);
 583                         if (rc)
 584                                 pr_err("Failed to add LMB, drc index %x\n",
 585                                        lmb->drc_index);
 586
 587                         drmem_remove_lmb_reservation(lmb);
 588                 }
 589                 rc = -EINVAL;
 590         } else {
 591                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 592                         if (!drmem_lmb_reserved(lmb))
 593                                 continue;
 594
 595                         dlpar_release_drc(lmb->drc_index);
 596                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 597                                 lmb->base_addr, lmb->drc_index);
 598
 599                         drmem_remove_lmb_reservation(lmb);
 600                 }
 601         }
 602
 603         return rc;
 604 }
 605
 606 #else
 607 static inline int pseries_remove_memblock(unsigned long base,
 608                                           unsigned long memblock_size)
 609 {
 610         return -EOPNOTSUPP;
 611 }
 612 static inline int pseries_remove_mem_node(struct device_node *np)
 613 {
 614         return 0;
 615 }
 616 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 617 {
 618         return -EOPNOTSUPP;
 619 }
 620 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 621 {
 622         return -EOPNOTSUPP;
 623 }
 624 static int dlpar_memory_remove_by_index(u32 drc_index)
 625 {
 626         return -EOPNOTSUPP;
 627 }
 628
 629 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 630 {
 631         return -EOPNOTSUPP;
 632 }
 633 #endif /* CONFIG_MEMORY_HOTREMOVE */
 634
 635 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 636 {
 637         unsigned long block_sz;
 638         int nid, rc;
 639
 640         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 641                 return -EINVAL;
 642
 643         rc = update_lmb_associativity_index(lmb);
 644         if (rc) {
 645                 dlpar_release_drc(lmb->drc_index);
 646                 return rc;
 647         }
 648
 649         block_sz = memory_block_size_bytes();
 650
 651         /* Find the node id for this LMB.  Fake one if necessary. */
 652         nid = of_drconf_to_nid_single(lmb);
 653         if (nid < 0 || !node_possible(nid))
 654                 nid = first_online_node;
 655
 656         /* Add the memory */
 657         rc = __add_memory(nid, lmb->base_addr, block_sz, MHP_NONE);
 658         if (rc) {
 659                 invalidate_lmb_associativity_index(lmb);
 660                 return rc;
 661         }
 662
 663         rc = dlpar_online_lmb(lmb);
 664         if (rc) {
 665                 __remove_memory(nid, lmb->base_addr, block_sz);
 666                 invalidate_lmb_associativity_index(lmb);
 667         } else {
 668                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 669         }
 670
 671         return rc;
 672 }
 673
 674 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 675 {
 676         struct drmem_lmb *lmb;
 677         int lmbs_available = 0;
 678         int lmbs_reserved = 0;
 679         int rc;
 680
 681         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 682
 683         if (lmbs_to_add == 0)
 684                 return -EINVAL;
 685
 686         /* Validate that there are enough LMBs to satisfy the request */
 687         for_each_drmem_lmb(lmb) {
 688                 if (lmb->flags & DRCONF_MEM_RESERVED)
 689                         continue;
 690
 691                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 692                         lmbs_available++;
 693
 694                 if (lmbs_available == lmbs_to_add)
 695                         break;
 696         }
 697
 698         if (lmbs_available < lmbs_to_add)
 699                 return -EINVAL;
 700
 701         for_each_drmem_lmb(lmb) {
 702                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 703                         continue;
 704
 705                 rc = dlpar_acquire_drc(lmb->drc_index);
 706                 if (rc)
 707                         continue;
 708
 709                 rc = dlpar_add_lmb(lmb);
 710                 if (rc) {
 711                         dlpar_release_drc(lmb->drc_index);
 712                         continue;
 713                 }
 714
 715                 /* Mark this lmb so we can remove it later if all of the
 716                  * requested LMBs cannot be added.
 717                  */
 718                 drmem_mark_lmb_reserved(lmb);
 719                 lmbs_reserved++;
 720                 if (lmbs_reserved == lmbs_to_add)
 721                         break;
 722         }
 723
 724         if (lmbs_reserved != lmbs_to_add) {
 725                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 726
 727                 for_each_drmem_lmb(lmb) {
 728                         if (!drmem_lmb_reserved(lmb))
 729                                 continue;
 730
 731                         rc = dlpar_remove_lmb(lmb);
 732                         if (rc)
 733                                 pr_err("Failed to remove LMB, drc index %x\n",
 734                                        lmb->drc_index);
 735                         else
 736                                 dlpar_release_drc(lmb->drc_index);
 737
 738                         drmem_remove_lmb_reservation(lmb);
 739                         lmbs_reserved--;
 740
 741                         if (lmbs_reserved == 0)
 742                                 break;
 743                 }
 744                 rc = -EINVAL;
 745         } else {
 746                 for_each_drmem_lmb(lmb) {
 747                         if (!drmem_lmb_reserved(lmb))
 748                                 continue;
 749
 750                         pr_debug("Memory at %llx (drc index %x) was hot-added\n",
 751                                  lmb->base_addr, lmb->drc_index);
 752                         drmem_remove_lmb_reservation(lmb);
 753                         lmbs_reserved--;
 754
 755                         if (lmbs_reserved == 0)
 756                                 break;
 757                 }
 758                 rc = 0;
 759         }
 760
 761         return rc;
 762 }
 763
 764 static int dlpar_memory_add_by_index(u32 drc_index)
 765 {
 766         struct drmem_lmb *lmb;
 767         int rc, lmb_found;
 768
 769         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 770
 771         lmb_found = 0;
 772         for_each_drmem_lmb(lmb) {
 773                 if (lmb->drc_index == drc_index) {
 774                         lmb_found = 1;
 775                         rc = dlpar_acquire_drc(lmb->drc_index);
 776                         if (!rc) {
 777                                 rc = dlpar_add_lmb(lmb);
 778                                 if (rc)
 779                                         dlpar_release_drc(lmb->drc_index);
 780                         }
 781
 782                         break;
 783                 }
 784         }
 785
 786         if (!lmb_found)
 787                 rc = -EINVAL;
 788
 789         if (rc)
 790                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 791         else
 792                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 793                         lmb->base_addr, drc_index);
 794
 795         return rc;
 796 }
 797
 798 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 799 {
 800         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 801         int rc;
 802
 803         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 804                 lmbs_to_add, drc_index);
 805
 806         if (lmbs_to_add == 0)
 807                 return -EINVAL;
 808
 809         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 810         if (rc)
 811                 return -EINVAL;
 812
 813         /* Validate that the LMBs in this range are not reserved */
 814         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 815                 /* Fail immediately if the whole range can't be hot-added */
 816                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 817                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 818                                         lmb->base_addr, lmb->drc_index);
 819                         return -EINVAL;
 820                 }
 821         }
 822
 823         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 824                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 825                         continue;
 826
 827                 rc = dlpar_acquire_drc(lmb->drc_index);
 828                 if (rc)
 829                         break;
 830
 831                 rc = dlpar_add_lmb(lmb);
 832                 if (rc) {
 833                         dlpar_release_drc(lmb->drc_index);
 834                         break;
 835                 }
 836
 837                 drmem_mark_lmb_reserved(lmb);
 838         }
 839
 840         if (rc) {
 841                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 842
 843                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 844                         if (!drmem_lmb_reserved(lmb))
 845                                 continue;
 846
 847                         rc = dlpar_remove_lmb(lmb);
 848                         if (rc)
 849                                 pr_err("Failed to remove LMB, drc index %x\n",
 850                                        lmb->drc_index);
 851                         else
 852                                 dlpar_release_drc(lmb->drc_index);
 853
 854                         drmem_remove_lmb_reservation(lmb);
 855                 }
 856                 rc = -EINVAL;
 857         } else {
 858                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 859                         if (!drmem_lmb_reserved(lmb))
 860                                 continue;
 861
 862                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 863                                 lmb->base_addr, lmb->drc_index);
 864                         drmem_remove_lmb_reservation(lmb);
 865                 }
 866         }
 867
 868         return rc;
 869 }
 870
 871 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 872 {
 873         u32 count, drc_index;
 874         int rc;
 875
 876         lock_device_hotplug();
 877
 878         switch (hp_elog->action) {
 879         case PSERIES_HP_ELOG_ACTION_ADD:
 880                 switch (hp_elog->id_type) {
 881                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 882                         count = hp_elog->_drc_u.drc_count;
 883                         rc = dlpar_memory_add_by_count(count);
 884                         break;
 885                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 886                         drc_index = hp_elog->_drc_u.drc_index;
 887                         rc = dlpar_memory_add_by_index(drc_index);
 888                         break;
 889                 case PSERIES_HP_ELOG_ID_DRC_IC:
 890                         count = hp_elog->_drc_u.ic.count;
 891                         drc_index = hp_elog->_drc_u.ic.index;
 892                         rc = dlpar_memory_add_by_ic(count, drc_index);
 893                         break;
 894                 default:
 895                         rc = -EINVAL;
 896                         break;
 897                 }
 898
 899                 break;
 900         case PSERIES_HP_ELOG_ACTION_REMOVE:
 901                 switch (hp_elog->id_type) {
 902                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 903                         count = hp_elog->_drc_u.drc_count;
 904                         rc = dlpar_memory_remove_by_count(count);
 905                         break;
 906                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 907                         drc_index = hp_elog->_drc_u.drc_index;
 908                         rc = dlpar_memory_remove_by_index(drc_index);
 909                         break;
 910                 case PSERIES_HP_ELOG_ID_DRC_IC:
 911                         count = hp_elog->_drc_u.ic.count;
 912                         drc_index = hp_elog->_drc_u.ic.index;
 913                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 914                         break;
 915                 default:
 916                         rc = -EINVAL;
 917                         break;
 918                 }
 919
 920                 break;
 921         default:
 922                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 923                 rc = -EINVAL;
 924                 break;
 925         }
 926
 927         if (!rc)
 928                 rc = drmem_update_dt();
 929
 930         unlock_device_hotplug();
 931         return rc;
 932 }
 933
 934 static int pseries_add_mem_node(struct device_node *np)
 935 {
 936         const __be32 *prop;
 937         unsigned long base;
 938         unsigned long lmb_size;
 939         int ret = -EINVAL;
 940         int addr_cells, size_cells;
 941
 942         /*
 943          * Check to see if we are actually adding memory
 944          */
 945         if (!of_node_is_type(np, "memory"))
 946                 return 0;
 947
 948         /*
 949          * Find the base and size of the memblock
 950          */
 951         prop = of_get_property(np, "reg", NULL);
 952         if (!prop)
 953                 return ret;
 954
 955         addr_cells = of_n_addr_cells(np);
 956         size_cells = of_n_size_cells(np);
 957         /*
 958          * "reg" property represents (addr,size) tuple.
 959          */
 960         base = of_read_number(prop, addr_cells);
 961         prop += addr_cells;
 962         lmb_size = of_read_number(prop, size_cells);
 963
 964         /*
 965          * Update memory region to represent the memory add
 966          */
 967         ret = memblock_add(base, lmb_size);
 968         return (ret < 0) ? -EINVAL : 0;
 969 }
 970
 971 static int pseries_memory_notifier(struct notifier_block *nb,
 972                                    unsigned long action, void *data)
 973 {
 974         struct of_reconfig_data *rd = data;
 975         int err = 0;
 976
 977         switch (action) {
 978         case OF_RECONFIG_ATTACH_NODE:
 979                 err = pseries_add_mem_node(rd->dn);
 980                 break;
 981         case OF_RECONFIG_DETACH_NODE:
 982                 err = pseries_remove_mem_node(rd->dn);
 983                 break;
 984         case OF_RECONFIG_UPDATE_PROPERTY:
 985                 if (!strcmp(rd->dn->name,
 986                             "ibm,dynamic-reconfiguration-memory"))
 987                         drmem_update_lmbs(rd->prop);
 988         }
 989         return notifier_from_errno(err);
 990 }
 991
 992 static struct notifier_block pseries_mem_nb = {
 993         .notifier_call = pseries_memory_notifier,
 994 };
 995
 996 static int __init pseries_memory_hotplug_init(void)
 997 {
 998         if (firmware_has_feature(FW_FEATURE_LPAR))
 999                 of_reconfig_notifier_register(&pseries_mem_nb);
1000
1001         return 0;
1002 }
1003 machine_device_initcall(pseries, pseries_memory_hotplug_init);