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_ASSIGNED))
 354                 return false;
 355
 356 #ifdef CONFIG_FA_DUMP
 357         /*
 358          * Don't hot-remove memory that falls in fadump boot memory area
 359          * and memory that is reserved for capturing old kernel memory.
 360          */
 361         if (is_fadump_memory_area(lmb->base_addr, memory_block_size_bytes()))
 362                 return false;
 363 #endif
 364         /* device_offline() will determine if we can actually remove this lmb */
 365         return true;
 366 }
 367
 368 static int dlpar_add_lmb(struct drmem_lmb *);
 369
 370 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 371 {
 372         struct memory_block *mem_block;
 373         unsigned long block_sz;
 374         int rc;
 375
 376         if (!lmb_is_removable(lmb))
 377                 return -EINVAL;
 378
 379         mem_block = lmb_to_memblock(lmb);
 380         if (mem_block == NULL)
 381                 return -EINVAL;
 382
 383         rc = dlpar_offline_lmb(lmb);
 384         if (rc) {
 385                 put_device(&mem_block->dev);
 386                 return rc;
 387         }
 388
 389         block_sz = pseries_memory_block_size();
 390
 391         __remove_memory(mem_block->nid, lmb->base_addr, block_sz);
 392         put_device(&mem_block->dev);
 393
 394         /* Update memory regions for memory remove */
 395         memblock_remove(lmb->base_addr, block_sz);
 396
 397         invalidate_lmb_associativity_index(lmb);
 398         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 399
 400         return 0;
 401 }
 402
 403 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 404 {
 405         struct drmem_lmb *lmb;
 406         int lmbs_removed = 0;
 407         int lmbs_available = 0;
 408         int rc;
 409
 410         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 411
 412         if (lmbs_to_remove == 0)
 413                 return -EINVAL;
 414
 415         /* Validate that there are enough LMBs to satisfy the request */
 416         for_each_drmem_lmb(lmb) {
 417                 if (lmb_is_removable(lmb))
 418                         lmbs_available++;
 419
 420                 if (lmbs_available == lmbs_to_remove)
 421                         break;
 422         }
 423
 424         if (lmbs_available < lmbs_to_remove) {
 425                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 426                         lmbs_available, lmbs_to_remove);
 427                 return -EINVAL;
 428         }
 429
 430         for_each_drmem_lmb(lmb) {
 431                 rc = dlpar_remove_lmb(lmb);
 432                 if (rc)
 433                         continue;
 434
 435                 /* Mark this lmb so we can add it later if all of the
 436                  * requested LMBs cannot be removed.
 437                  */
 438                 drmem_mark_lmb_reserved(lmb);
 439
 440                 lmbs_removed++;
 441                 if (lmbs_removed == lmbs_to_remove)
 442                         break;
 443         }
 444
 445         if (lmbs_removed != lmbs_to_remove) {
 446                 pr_err("Memory hot-remove failed, adding LMB's back\n");
 447
 448                 for_each_drmem_lmb(lmb) {
 449                         if (!drmem_lmb_reserved(lmb))
 450                                 continue;
 451
 452                         rc = dlpar_add_lmb(lmb);
 453                         if (rc)
 454                                 pr_err("Failed to add LMB back, drc index %x\n",
 455                                        lmb->drc_index);
 456
 457                         drmem_remove_lmb_reservation(lmb);
 458                 }
 459
 460                 rc = -EINVAL;
 461         } else {
 462                 for_each_drmem_lmb(lmb) {
 463                         if (!drmem_lmb_reserved(lmb))
 464                                 continue;
 465
 466                         dlpar_release_drc(lmb->drc_index);
 467                         pr_info("Memory at %llx was hot-removed\n",
 468                                 lmb->base_addr);
 469
 470                         drmem_remove_lmb_reservation(lmb);
 471                 }
 472                 rc = 0;
 473         }
 474
 475         return rc;
 476 }
 477
 478 static int dlpar_memory_remove_by_index(u32 drc_index)
 479 {
 480         struct drmem_lmb *lmb;
 481         int lmb_found;
 482         int rc;
 483
 484         pr_debug("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 485
 486         lmb_found = 0;
 487         for_each_drmem_lmb(lmb) {
 488                 if (lmb->drc_index == drc_index) {
 489                         lmb_found = 1;
 490                         rc = dlpar_remove_lmb(lmb);
 491                         if (!rc)
 492                                 dlpar_release_drc(lmb->drc_index);
 493
 494                         break;
 495                 }
 496         }
 497
 498         if (!lmb_found) {
 499                 pr_debug("Failed to look up LMB for drc index %x\n", drc_index);
 500                 rc = -EINVAL;
 501         } else if (rc) {
 502                 pr_debug("Failed to hot-remove memory at %llx\n",
 503                          lmb->base_addr);
 504         } else {
 505                 pr_debug("Memory at %llx was hot-removed\n", lmb->base_addr);
 506         }
 507
 508         return rc;
 509 }
 510
 511 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 512 {
 513         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 514         int lmbs_available = 0;
 515         int rc;
 516
 517         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 518                 lmbs_to_remove, drc_index);
 519
 520         if (lmbs_to_remove == 0)
 521                 return -EINVAL;
 522
 523         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 524         if (rc)
 525                 return -EINVAL;
 526
 527         /* Validate that there are enough LMBs to satisfy the request */
 528         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 529                 if (lmb->flags & DRCONF_MEM_RESERVED)
 530                         break;
 531
 532                 lmbs_available++;
 533         }
 534
 535         if (lmbs_available < lmbs_to_remove)
 536                 return -EINVAL;
 537
 538         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 539                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 540                         continue;
 541
 542                 rc = dlpar_remove_lmb(lmb);
 543                 if (rc)
 544                         break;
 545
 546                 drmem_mark_lmb_reserved(lmb);
 547         }
 548
 549         if (rc) {
 550                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 551
 552
 553                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 554                         if (!drmem_lmb_reserved(lmb))
 555                                 continue;
 556
 557                         rc = dlpar_add_lmb(lmb);
 558                         if (rc)
 559                                 pr_err("Failed to add LMB, drc index %x\n",
 560                                        lmb->drc_index);
 561
 562                         drmem_remove_lmb_reservation(lmb);
 563                 }
 564                 rc = -EINVAL;
 565         } else {
 566                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 567                         if (!drmem_lmb_reserved(lmb))
 568                                 continue;
 569
 570                         dlpar_release_drc(lmb->drc_index);
 571                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 572                                 lmb->base_addr, lmb->drc_index);
 573
 574                         drmem_remove_lmb_reservation(lmb);
 575                 }
 576         }
 577
 578         return rc;
 579 }
 580
 581 #else
 582 static inline int pseries_remove_memblock(unsigned long base,
 583                                           unsigned long memblock_size)
 584 {
 585         return -EOPNOTSUPP;
 586 }
 587 static inline int pseries_remove_mem_node(struct device_node *np)
 588 {
 589         return 0;
 590 }
 591 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
 592 {
 593         return -EOPNOTSUPP;
 594 }
 595 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 596 {
 597         return -EOPNOTSUPP;
 598 }
 599 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 600 {
 601         return -EOPNOTSUPP;
 602 }
 603 static int dlpar_memory_remove_by_index(u32 drc_index)
 604 {
 605         return -EOPNOTSUPP;
 606 }
 607
 608 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 609 {
 610         return -EOPNOTSUPP;
 611 }
 612 #endif /* CONFIG_MEMORY_HOTREMOVE */
 613
 614 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 615 {
 616         unsigned long block_sz;
 617         int nid, rc;
 618
 619         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 620                 return -EINVAL;
 621
 622         rc = update_lmb_associativity_index(lmb);
 623         if (rc) {
 624                 dlpar_release_drc(lmb->drc_index);
 625                 return rc;
 626         }
 627
 628         block_sz = memory_block_size_bytes();
 629
 630         /* Find the node id for this LMB.  Fake one if necessary. */
 631         nid = of_drconf_to_nid_single(lmb);
 632         if (nid < 0 || !node_possible(nid))
 633                 nid = first_online_node;
 634
 635         /* Add the memory */
 636         rc = __add_memory(nid, lmb->base_addr, block_sz, MHP_NONE);
 637         if (rc) {
 638                 invalidate_lmb_associativity_index(lmb);
 639                 return rc;
 640         }
 641
 642         rc = dlpar_online_lmb(lmb);
 643         if (rc) {
 644                 __remove_memory(nid, lmb->base_addr, block_sz);
 645                 invalidate_lmb_associativity_index(lmb);
 646         } else {
 647                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 648         }
 649
 650         return rc;
 651 }
 652
 653 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 654 {
 655         struct drmem_lmb *lmb;
 656         int lmbs_available = 0;
 657         int lmbs_added = 0;
 658         int rc;
 659
 660         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 661
 662         if (lmbs_to_add == 0)
 663                 return -EINVAL;
 664
 665         /* Validate that there are enough LMBs to satisfy the request */
 666         for_each_drmem_lmb(lmb) {
 667                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 668                         lmbs_available++;
 669
 670                 if (lmbs_available == lmbs_to_add)
 671                         break;
 672         }
 673
 674         if (lmbs_available < lmbs_to_add)
 675                 return -EINVAL;
 676
 677         for_each_drmem_lmb(lmb) {
 678                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 679                         continue;
 680
 681                 rc = dlpar_acquire_drc(lmb->drc_index);
 682                 if (rc)
 683                         continue;
 684
 685                 rc = dlpar_add_lmb(lmb);
 686                 if (rc) {
 687                         dlpar_release_drc(lmb->drc_index);
 688                         continue;
 689                 }
 690
 691                 /* Mark this lmb so we can remove it later if all of the
 692                  * requested LMBs cannot be added.
 693                  */
 694                 drmem_mark_lmb_reserved(lmb);
 695
 696                 lmbs_added++;
 697                 if (lmbs_added == lmbs_to_add)
 698                         break;
 699         }
 700
 701         if (lmbs_added != lmbs_to_add) {
 702                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 703
 704                 for_each_drmem_lmb(lmb) {
 705                         if (!drmem_lmb_reserved(lmb))
 706                                 continue;
 707
 708                         rc = dlpar_remove_lmb(lmb);
 709                         if (rc)
 710                                 pr_err("Failed to remove LMB, drc index %x\n",
 711                                        lmb->drc_index);
 712                         else
 713                                 dlpar_release_drc(lmb->drc_index);
 714
 715                         drmem_remove_lmb_reservation(lmb);
 716                 }
 717                 rc = -EINVAL;
 718         } else {
 719                 for_each_drmem_lmb(lmb) {
 720                         if (!drmem_lmb_reserved(lmb))
 721                                 continue;
 722
 723                         pr_debug("Memory at %llx (drc index %x) was hot-added\n",
 724                                  lmb->base_addr, lmb->drc_index);
 725                         drmem_remove_lmb_reservation(lmb);
 726                 }
 727                 rc = 0;
 728         }
 729
 730         return rc;
 731 }
 732
 733 static int dlpar_memory_add_by_index(u32 drc_index)
 734 {
 735         struct drmem_lmb *lmb;
 736         int rc, lmb_found;
 737
 738         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 739
 740         lmb_found = 0;
 741         for_each_drmem_lmb(lmb) {
 742                 if (lmb->drc_index == drc_index) {
 743                         lmb_found = 1;
 744                         rc = dlpar_acquire_drc(lmb->drc_index);
 745                         if (!rc) {
 746                                 rc = dlpar_add_lmb(lmb);
 747                                 if (rc)
 748                                         dlpar_release_drc(lmb->drc_index);
 749                         }
 750
 751                         break;
 752                 }
 753         }
 754
 755         if (!lmb_found)
 756                 rc = -EINVAL;
 757
 758         if (rc)
 759                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 760         else
 761                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 762                         lmb->base_addr, drc_index);
 763
 764         return rc;
 765 }
 766
 767 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 768 {
 769         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 770         int lmbs_available = 0;
 771         int rc;
 772
 773         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 774                 lmbs_to_add, drc_index);
 775
 776         if (lmbs_to_add == 0)
 777                 return -EINVAL;
 778
 779         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 780         if (rc)
 781                 return -EINVAL;
 782
 783         /* Validate that the LMBs in this range are not reserved */
 784         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 785                 if (lmb->flags & DRCONF_MEM_RESERVED)
 786                         break;
 787
 788                 lmbs_available++;
 789         }
 790
 791         if (lmbs_available < lmbs_to_add)
 792                 return -EINVAL;
 793
 794         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 795                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 796                         continue;
 797
 798                 rc = dlpar_acquire_drc(lmb->drc_index);
 799                 if (rc)
 800                         break;
 801
 802                 rc = dlpar_add_lmb(lmb);
 803                 if (rc) {
 804                         dlpar_release_drc(lmb->drc_index);
 805                         break;
 806                 }
 807
 808                 drmem_mark_lmb_reserved(lmb);
 809         }
 810
 811         if (rc) {
 812                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 813
 814                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 815                         if (!drmem_lmb_reserved(lmb))
 816                                 continue;
 817
 818                         rc = dlpar_remove_lmb(lmb);
 819                         if (rc)
 820                                 pr_err("Failed to remove LMB, drc index %x\n",
 821                                        lmb->drc_index);
 822                         else
 823                                 dlpar_release_drc(lmb->drc_index);
 824
 825                         drmem_remove_lmb_reservation(lmb);
 826                 }
 827                 rc = -EINVAL;
 828         } else {
 829                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 830                         if (!drmem_lmb_reserved(lmb))
 831                                 continue;
 832
 833                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 834                                 lmb->base_addr, lmb->drc_index);
 835                         drmem_remove_lmb_reservation(lmb);
 836                 }
 837         }
 838
 839         return rc;
 840 }
 841
 842 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 843 {
 844         u32 count, drc_index;
 845         int rc;
 846
 847         lock_device_hotplug();
 848
 849         switch (hp_elog->action) {
 850         case PSERIES_HP_ELOG_ACTION_ADD:
 851                 switch (hp_elog->id_type) {
 852                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 853                         count = hp_elog->_drc_u.drc_count;
 854                         rc = dlpar_memory_add_by_count(count);
 855                         break;
 856                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 857                         drc_index = hp_elog->_drc_u.drc_index;
 858                         rc = dlpar_memory_add_by_index(drc_index);
 859                         break;
 860                 case PSERIES_HP_ELOG_ID_DRC_IC:
 861                         count = hp_elog->_drc_u.ic.count;
 862                         drc_index = hp_elog->_drc_u.ic.index;
 863                         rc = dlpar_memory_add_by_ic(count, drc_index);
 864                         break;
 865                 default:
 866                         rc = -EINVAL;
 867                         break;
 868                 }
 869
 870                 break;
 871         case PSERIES_HP_ELOG_ACTION_REMOVE:
 872                 switch (hp_elog->id_type) {
 873                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 874                         count = hp_elog->_drc_u.drc_count;
 875                         rc = dlpar_memory_remove_by_count(count);
 876                         break;
 877                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 878                         drc_index = hp_elog->_drc_u.drc_index;
 879                         rc = dlpar_memory_remove_by_index(drc_index);
 880                         break;
 881                 case PSERIES_HP_ELOG_ID_DRC_IC:
 882                         count = hp_elog->_drc_u.ic.count;
 883                         drc_index = hp_elog->_drc_u.ic.index;
 884                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 885                         break;
 886                 default:
 887                         rc = -EINVAL;
 888                         break;
 889                 }
 890
 891                 break;
 892         default:
 893                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 894                 rc = -EINVAL;
 895                 break;
 896         }
 897
 898         if (!rc)
 899                 rc = drmem_update_dt();
 900
 901         unlock_device_hotplug();
 902         return rc;
 903 }
 904
 905 static int pseries_add_mem_node(struct device_node *np)
 906 {
 907         const __be32 *prop;
 908         unsigned long base;
 909         unsigned long lmb_size;
 910         int ret = -EINVAL;
 911         int addr_cells, size_cells;
 912
 913         /*
 914          * Check to see if we are actually adding memory
 915          */
 916         if (!of_node_is_type(np, "memory"))
 917                 return 0;
 918
 919         /*
 920          * Find the base and size of the memblock
 921          */
 922         prop = of_get_property(np, "reg", NULL);
 923         if (!prop)
 924                 return ret;
 925
 926         addr_cells = of_n_addr_cells(np);
 927         size_cells = of_n_size_cells(np);
 928         /*
 929          * "reg" property represents (addr,size) tuple.
 930          */
 931         base = of_read_number(prop, addr_cells);
 932         prop += addr_cells;
 933         lmb_size = of_read_number(prop, size_cells);
 934
 935         /*
 936          * Update memory region to represent the memory add
 937          */
 938         ret = memblock_add(base, lmb_size);
 939         return (ret < 0) ? -EINVAL : 0;
 940 }
 941
 942 static int pseries_memory_notifier(struct notifier_block *nb,
 943                                    unsigned long action, void *data)
 944 {
 945         struct of_reconfig_data *rd = data;
 946         int err = 0;
 947
 948         switch (action) {
 949         case OF_RECONFIG_ATTACH_NODE:
 950                 err = pseries_add_mem_node(rd->dn);
 951                 break;
 952         case OF_RECONFIG_DETACH_NODE:
 953                 err = pseries_remove_mem_node(rd->dn);
 954                 break;
 955         }
 956         return notifier_from_errno(err);
 957 }
 958
 959 static struct notifier_block pseries_mem_nb = {
 960         .notifier_call = pseries_memory_notifier,
 961 };
 962
 963 static int __init pseries_memory_hotplug_init(void)
 964 {
 965         if (firmware_has_feature(FW_FEATURE_LPAR))
 966                 of_reconfig_notifier_register(&pseries_mem_nb);
 967
 968         return 0;
 969 }
 970 machine_device_initcall(pseries, pseries_memory_hotplug_init);