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         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 184         if (!dr_node) {
 185                 dlpar_free_cc_nodes(lmb_node);
 186                 return -ENODEV;
 187         }
 188
 189         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
 190                                     NULL);
 191         if (!ala_prop) {
 192                 of_node_put(dr_node);
 193                 dlpar_free_cc_nodes(lmb_node);
 194                 return -ENODEV;
 195         }
 196
 197         found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);
 198
 199         of_node_put(dr_node);
 200         dlpar_free_cc_nodes(lmb_node);
 201
 202         if (!found) {
 203                 pr_err("Could not find LMB associativity\n");
 204                 return -1;
 205         }
 206
 207         lmb->aa_index = aa_index;
 208         return 0;
 209 }
 210
 211 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 212 {
 213         unsigned long section_nr;
 214         struct mem_section *mem_sect;
 215         struct memory_block *mem_block;
 216
 217         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 218         mem_sect = __nr_to_section(section_nr);
 219
 220         mem_block = find_memory_block(mem_sect);
 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, nid;
 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         nid = memory_add_physaddr_to_nid(base);
 301
 302         for (i = 0; i < sections_per_block; i++) {
 303                 __remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
 304                 base += MIN_MEMORY_BLOCK_SIZE;
 305         }
 306
 307 out:
 308         /* Update memory regions for memory remove */
 309         memblock_remove(base, memblock_size);
 310         unlock_device_hotplug();
 311         return 0;
 312 }
 313
 314 static int pseries_remove_mem_node(struct device_node *np)
 315 {
 316         const __be32 *prop;
 317         unsigned long base;
 318         unsigned long lmb_size;
 319         int ret = -EINVAL;
 320         int addr_cells, size_cells;
 321
 322         /*
 323          * Check to see if we are actually removing memory
 324          */
 325         if (!of_node_is_type(np, "memory"))
 326                 return 0;
 327
 328         /*
 329          * Find the base address and size of the memblock
 330          */
 331         prop = of_get_property(np, "reg", NULL);
 332         if (!prop)
 333                 return ret;
 334
 335         addr_cells = of_n_addr_cells(np);
 336         size_cells = of_n_size_cells(np);
 337
 338         /*
 339          * "reg" property represents (addr,size) tuple.
 340          */
 341         base = of_read_number(prop, addr_cells);
 342         prop += addr_cells;
 343         lmb_size = of_read_number(prop, size_cells);
 344
 345         pseries_remove_memblock(base, lmb_size);
 346         return 0;
 347 }
 348
 349 static bool lmb_is_removable(struct drmem_lmb *lmb)
 350 {
 351         if (!(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(mem_block->nid, 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_removed = 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_removed++;
 439                 if (lmbs_removed == lmbs_to_remove)
 440                         break;
 441         }
 442
 443         if (lmbs_removed != 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
 458                 rc = -EINVAL;
 459         } else {
 460                 for_each_drmem_lmb(lmb) {
 461                         if (!drmem_lmb_reserved(lmb))
 462                                 continue;
 463
 464                         dlpar_release_drc(lmb->drc_index);
 465                         pr_info("Memory at %llx was hot-removed\n",
 466                                 lmb->base_addr);
 467
 468                         drmem_remove_lmb_reservation(lmb);
 469                 }
 470                 rc = 0;
 471         }
 472
 473         return rc;
 474 }
 475
 476 static int dlpar_memory_remove_by_index(u32 drc_index)
 477 {
 478         struct drmem_lmb *lmb;
 479         int lmb_found;
 480         int rc;
 481
 482         pr_debug("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 483
 484         lmb_found = 0;
 485         for_each_drmem_lmb(lmb) {
 486                 if (lmb->drc_index == drc_index) {
 487                         lmb_found = 1;
 488                         rc = dlpar_remove_lmb(lmb);
 489                         if (!rc)
 490                                 dlpar_release_drc(lmb->drc_index);
 491
 492                         break;
 493                 }
 494         }
 495
 496         if (!lmb_found)
 497                 rc = -EINVAL;
 498
 499         if (rc)
 500                 pr_debug("Failed to hot-remove memory at %llx\n",
 501                          lmb->base_addr);
 502         else
 503                 pr_debug("Memory at %llx was hot-removed\n", lmb->base_addr);
 504
 505         return rc;
 506 }
 507
 508 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 509 {
 510         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 511         int lmbs_available = 0;
 512         int rc;
 513
 514         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 515                 lmbs_to_remove, drc_index);
 516
 517         if (lmbs_to_remove == 0)
 518                 return -EINVAL;
 519
 520         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 521         if (rc)
 522                 return -EINVAL;
 523
 524         /* Validate that there are enough LMBs to satisfy the request */
 525         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 526                 if (lmb->flags & DRCONF_MEM_RESERVED)
 527                         break;
 528
 529                 lmbs_available++;
 530         }
 531
 532         if (lmbs_available < lmbs_to_remove)
 533                 return -EINVAL;
 534
 535         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 536                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 537                         continue;
 538
 539                 rc = dlpar_remove_lmb(lmb);
 540                 if (rc)
 541                         break;
 542
 543                 drmem_mark_lmb_reserved(lmb);
 544         }
 545
 546         if (rc) {
 547                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 548
 549
 550                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 551                         if (!drmem_lmb_reserved(lmb))
 552                                 continue;
 553
 554                         rc = dlpar_add_lmb(lmb);
 555                         if (rc)
 556                                 pr_err("Failed to add LMB, drc index %x\n",
 557                                        lmb->drc_index);
 558
 559                         drmem_remove_lmb_reservation(lmb);
 560                 }
 561                 rc = -EINVAL;
 562         } else {
 563                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 564                         if (!drmem_lmb_reserved(lmb))
 565                                 continue;
 566
 567                         dlpar_release_drc(lmb->drc_index);
 568                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 569                                 lmb->base_addr, lmb->drc_index);
 570
 571                         drmem_remove_lmb_reservation(lmb);
 572                 }
 573         }
 574
 575         return rc;
 576 }
 577
 578 #else
 579 static inline int pseries_remove_memblock(unsigned long base,
 580                                           unsigned long memblock_size)
 581 {
 582         return -EOPNOTSUPP;
 583 }
 584 static inline int pseries_remove_mem_node(struct device_node *np)
 585 {
 586         return 0;
 587 }
 588 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
 589 {
 590         return -EOPNOTSUPP;
 591 }
 592 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 593 {
 594         return -EOPNOTSUPP;
 595 }
 596 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 597 {
 598         return -EOPNOTSUPP;
 599 }
 600 static int dlpar_memory_remove_by_index(u32 drc_index)
 601 {
 602         return -EOPNOTSUPP;
 603 }
 604
 605 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 606 {
 607         return -EOPNOTSUPP;
 608 }
 609 #endif /* CONFIG_MEMORY_HOTREMOVE */
 610
 611 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 612 {
 613         unsigned long block_sz;
 614         int nid, rc;
 615
 616         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 617                 return -EINVAL;
 618
 619         rc = update_lmb_associativity_index(lmb);
 620         if (rc) {
 621                 dlpar_release_drc(lmb->drc_index);
 622                 return rc;
 623         }
 624
 625         block_sz = memory_block_size_bytes();
 626
 627         /* Find the node id for this LMB.  Fake one if necessary. */
 628         nid = of_drconf_to_nid_single(lmb);
 629         if (nid < 0 || !node_possible(nid))
 630                 nid = first_online_node;
 631
 632         /* Add the memory */
 633         rc = __add_memory(nid, lmb->base_addr, block_sz, MHP_NONE);
 634         if (rc) {
 635                 invalidate_lmb_associativity_index(lmb);
 636                 return rc;
 637         }
 638
 639         rc = dlpar_online_lmb(lmb);
 640         if (rc) {
 641                 __remove_memory(nid, lmb->base_addr, block_sz);
 642                 invalidate_lmb_associativity_index(lmb);
 643         } else {
 644                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 645         }
 646
 647         return rc;
 648 }
 649
 650 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 651 {
 652         struct drmem_lmb *lmb;
 653         int lmbs_available = 0;
 654         int lmbs_added = 0;
 655         int rc;
 656
 657         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 658
 659         if (lmbs_to_add == 0)
 660                 return -EINVAL;
 661
 662         /* Validate that there are enough LMBs to satisfy the request */
 663         for_each_drmem_lmb(lmb) {
 664                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 665                         lmbs_available++;
 666
 667                 if (lmbs_available == lmbs_to_add)
 668                         break;
 669         }
 670
 671         if (lmbs_available < lmbs_to_add)
 672                 return -EINVAL;
 673
 674         for_each_drmem_lmb(lmb) {
 675                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 676                         continue;
 677
 678                 rc = dlpar_acquire_drc(lmb->drc_index);
 679                 if (rc)
 680                         continue;
 681
 682                 rc = dlpar_add_lmb(lmb);
 683                 if (rc) {
 684                         dlpar_release_drc(lmb->drc_index);
 685                         continue;
 686                 }
 687
 688                 /* Mark this lmb so we can remove it later if all of the
 689                  * requested LMBs cannot be added.
 690                  */
 691                 drmem_mark_lmb_reserved(lmb);
 692
 693                 lmbs_added++;
 694                 if (lmbs_added == lmbs_to_add)
 695                         break;
 696         }
 697
 698         if (lmbs_added != lmbs_to_add) {
 699                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 700
 701                 for_each_drmem_lmb(lmb) {
 702                         if (!drmem_lmb_reserved(lmb))
 703                                 continue;
 704
 705                         rc = dlpar_remove_lmb(lmb);
 706                         if (rc)
 707                                 pr_err("Failed to remove LMB, drc index %x\n",
 708                                        lmb->drc_index);
 709                         else
 710                                 dlpar_release_drc(lmb->drc_index);
 711
 712                         drmem_remove_lmb_reservation(lmb);
 713                 }
 714                 rc = -EINVAL;
 715         } else {
 716                 for_each_drmem_lmb(lmb) {
 717                         if (!drmem_lmb_reserved(lmb))
 718                                 continue;
 719
 720                         pr_debug("Memory at %llx (drc index %x) was hot-added\n",
 721                                  lmb->base_addr, lmb->drc_index);
 722                         drmem_remove_lmb_reservation(lmb);
 723                 }
 724                 rc = 0;
 725         }
 726
 727         return rc;
 728 }
 729
 730 static int dlpar_memory_add_by_index(u32 drc_index)
 731 {
 732         struct drmem_lmb *lmb;
 733         int rc, lmb_found;
 734
 735         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 736
 737         lmb_found = 0;
 738         for_each_drmem_lmb(lmb) {
 739                 if (lmb->drc_index == drc_index) {
 740                         lmb_found = 1;
 741                         rc = dlpar_acquire_drc(lmb->drc_index);
 742                         if (!rc) {
 743                                 rc = dlpar_add_lmb(lmb);
 744                                 if (rc)
 745                                         dlpar_release_drc(lmb->drc_index);
 746                         }
 747
 748                         break;
 749                 }
 750         }
 751
 752         if (!lmb_found)
 753                 rc = -EINVAL;
 754
 755         if (rc)
 756                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 757         else
 758                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 759                         lmb->base_addr, drc_index);
 760
 761         return rc;
 762 }
 763
 764 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 765 {
 766         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 767         int lmbs_available = 0;
 768         int rc;
 769
 770         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 771                 lmbs_to_add, drc_index);
 772
 773         if (lmbs_to_add == 0)
 774                 return -EINVAL;
 775
 776         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 777         if (rc)
 778                 return -EINVAL;
 779
 780         /* Validate that the LMBs in this range are not reserved */
 781         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 782                 if (lmb->flags & DRCONF_MEM_RESERVED)
 783                         break;
 784
 785                 lmbs_available++;
 786         }
 787
 788         if (lmbs_available < lmbs_to_add)
 789                 return -EINVAL;
 790
 791         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 792                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 793                         continue;
 794
 795                 rc = dlpar_acquire_drc(lmb->drc_index);
 796                 if (rc)
 797                         break;
 798
 799                 rc = dlpar_add_lmb(lmb);
 800                 if (rc) {
 801                         dlpar_release_drc(lmb->drc_index);
 802                         break;
 803                 }
 804
 805                 drmem_mark_lmb_reserved(lmb);
 806         }
 807
 808         if (rc) {
 809                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 810
 811                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 812                         if (!drmem_lmb_reserved(lmb))
 813                                 continue;
 814
 815                         rc = dlpar_remove_lmb(lmb);
 816                         if (rc)
 817                                 pr_err("Failed to remove LMB, drc index %x\n",
 818                                        lmb->drc_index);
 819                         else
 820                                 dlpar_release_drc(lmb->drc_index);
 821
 822                         drmem_remove_lmb_reservation(lmb);
 823                 }
 824                 rc = -EINVAL;
 825         } else {
 826                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 827                         if (!drmem_lmb_reserved(lmb))
 828                                 continue;
 829
 830                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 831                                 lmb->base_addr, lmb->drc_index);
 832                         drmem_remove_lmb_reservation(lmb);
 833                 }
 834         }
 835
 836         return rc;
 837 }
 838
 839 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 840 {
 841         u32 count, drc_index;
 842         int rc;
 843
 844         lock_device_hotplug();
 845
 846         switch (hp_elog->action) {
 847         case PSERIES_HP_ELOG_ACTION_ADD:
 848                 switch (hp_elog->id_type) {
 849                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 850                         count = hp_elog->_drc_u.drc_count;
 851                         rc = dlpar_memory_add_by_count(count);
 852                         break;
 853                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 854                         drc_index = hp_elog->_drc_u.drc_index;
 855                         rc = dlpar_memory_add_by_index(drc_index);
 856                         break;
 857                 case PSERIES_HP_ELOG_ID_DRC_IC:
 858                         count = hp_elog->_drc_u.ic.count;
 859                         drc_index = hp_elog->_drc_u.ic.index;
 860                         rc = dlpar_memory_add_by_ic(count, drc_index);
 861                         break;
 862                 default:
 863                         rc = -EINVAL;
 864                         break;
 865                 }
 866
 867                 break;
 868         case PSERIES_HP_ELOG_ACTION_REMOVE:
 869                 switch (hp_elog->id_type) {
 870                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 871                         count = hp_elog->_drc_u.drc_count;
 872                         rc = dlpar_memory_remove_by_count(count);
 873                         break;
 874                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 875                         drc_index = hp_elog->_drc_u.drc_index;
 876                         rc = dlpar_memory_remove_by_index(drc_index);
 877                         break;
 878                 case PSERIES_HP_ELOG_ID_DRC_IC:
 879                         count = hp_elog->_drc_u.ic.count;
 880                         drc_index = hp_elog->_drc_u.ic.index;
 881                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 882                         break;
 883                 default:
 884                         rc = -EINVAL;
 885                         break;
 886                 }
 887
 888                 break;
 889         default:
 890                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 891                 rc = -EINVAL;
 892                 break;
 893         }
 894
 895         if (!rc)
 896                 rc = drmem_update_dt();
 897
 898         unlock_device_hotplug();
 899         return rc;
 900 }
 901
 902 static int pseries_add_mem_node(struct device_node *np)
 903 {
 904         const __be32 *prop;
 905         unsigned long base;
 906         unsigned long lmb_size;
 907         int ret = -EINVAL;
 908         int addr_cells, size_cells;
 909
 910         /*
 911          * Check to see if we are actually adding memory
 912          */
 913         if (!of_node_is_type(np, "memory"))
 914                 return 0;
 915
 916         /*
 917          * Find the base and size of the memblock
 918          */
 919         prop = of_get_property(np, "reg", NULL);
 920         if (!prop)
 921                 return ret;
 922
 923         addr_cells = of_n_addr_cells(np);
 924         size_cells = of_n_size_cells(np);
 925         /*
 926          * "reg" property represents (addr,size) tuple.
 927          */
 928         base = of_read_number(prop, addr_cells);
 929         prop += addr_cells;
 930         lmb_size = of_read_number(prop, size_cells);
 931
 932         /*
 933          * Update memory region to represent the memory add
 934          */
 935         ret = memblock_add(base, lmb_size);
 936         return (ret < 0) ? -EINVAL : 0;
 937 }
 938
 939 static int pseries_memory_notifier(struct notifier_block *nb,
 940                                    unsigned long action, void *data)
 941 {
 942         struct of_reconfig_data *rd = data;
 943         int err = 0;
 944
 945         switch (action) {
 946         case OF_RECONFIG_ATTACH_NODE:
 947                 err = pseries_add_mem_node(rd->dn);
 948                 break;
 949         case OF_RECONFIG_DETACH_NODE:
 950                 err = pseries_remove_mem_node(rd->dn);
 951                 break;
 952         }
 953         return notifier_from_errno(err);
 954 }
 955
 956 static struct notifier_block pseries_mem_nb = {
 957         .notifier_call = pseries_memory_notifier,
 958 };
 959
 960 static int __init pseries_memory_hotplug_init(void)
 961 {
 962         if (firmware_has_feature(FW_FEATURE_LPAR))
 963                 of_reconfig_notifier_register(&pseries_mem_nb);
 964
 965         return 0;
 966 }
 967 machine_device_initcall(pseries, pseries_memory_hotplug_init);