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

   1 /*
   2  * pseries Memory Hotplug infrastructure.
   3  *
   4  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
   5  *
   6  *      This program is free software; you can redistribute it and/or
   7  *      modify it under the terms of the GNU General Public License
   8  *      as published by the Free Software Foundation; either version
   9  *      2 of the License, or (at your option) any later version.
  10  */
  11
  12 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
  13
  14 #include <linux/of.h>
  15 #include <linux/of_address.h>
  16 #include <linux/memblock.h>
  17 #include <linux/memory.h>
  18 #include <linux/memory_hotplug.h>
  19 #include <linux/slab.h>
  20
  21 #include <asm/firmware.h>
  22 #include <asm/machdep.h>
  23 #include <asm/prom.h>
  24 #include <asm/sparsemem.h>
  25 #include <asm/fadump.h>
  26 #include <asm/drmem.h>
  27 #include "pseries.h"
  28
  29 static bool rtas_hp_event;
  30
  31 unsigned long pseries_memory_block_size(void)
  32 {
  33         struct device_node *np;
  34         unsigned int memblock_size = MIN_MEMORY_BLOCK_SIZE;
  35         struct resource r;
  36
  37         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
  38         if (np) {
  39                 const __be64 *size;
  40
  41                 size = of_get_property(np, "ibm,lmb-size", NULL);
  42                 if (size)
  43                         memblock_size = be64_to_cpup(size);
  44                 of_node_put(np);
  45         } else  if (machine_is(pseries)) {
  46                 /* This fallback really only applies to pseries */
  47                 unsigned int memzero_size = 0;
  48
  49                 np = of_find_node_by_path("/memory@0");
  50                 if (np) {
  51                         if (!of_address_to_resource(np, 0, &r))
  52                                 memzero_size = resource_size(&r);
  53                         of_node_put(np);
  54                 }
  55
  56                 if (memzero_size) {
  57                         /* We now know the size of memory@0, use this to find
  58                          * the first memoryblock and get its size.
  59                          */
  60                         char buf[64];
  61
  62                         sprintf(buf, "/memory@%x", memzero_size);
  63                         np = of_find_node_by_path(buf);
  64                         if (np) {
  65                                 if (!of_address_to_resource(np, 0, &r))
  66                                         memblock_size = resource_size(&r);
  67                                 of_node_put(np);
  68                         }
  69                 }
  70         }
  71         return memblock_size;
  72 }
  73
  74 static void dlpar_free_property(struct property *prop)
  75 {
  76         kfree(prop->name);
  77         kfree(prop->value);
  78         kfree(prop);
  79 }
  80
  81 static struct property *dlpar_clone_property(struct property *prop,
  82                                              u32 prop_size)
  83 {
  84         struct property *new_prop;
  85
  86         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
  87         if (!new_prop)
  88                 return NULL;
  89
  90         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
  91         new_prop->value = kzalloc(prop_size, GFP_KERNEL);
  92         if (!new_prop->name || !new_prop->value) {
  93                 dlpar_free_property(new_prop);
  94                 return NULL;
  95         }
  96
  97         memcpy(new_prop->value, prop->value, prop->length);
  98         new_prop->length = prop_size;
  99
 100         of_property_set_flag(new_prop, OF_DYNAMIC);
 101         return new_prop;
 102 }
 103
 104 static u32 find_aa_index(struct device_node *dr_node,
 105                          struct property *ala_prop, const u32 *lmb_assoc)
 106 {
 107         u32 *assoc_arrays;
 108         u32 aa_index;
 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         aa_index = -1;
 125         for (i = 0; i < aa_arrays; i++) {
 126                 index = (i * aa_array_entries) + 2;
 127
 128                 if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
 129                         continue;
 130
 131                 aa_index = i;
 132                 break;
 133         }
 134
 135         if (aa_index == -1) {
 136                 struct property *new_prop;
 137                 u32 new_prop_size;
 138
 139                 new_prop_size = ala_prop->length + aa_array_sz;
 140                 new_prop = dlpar_clone_property(ala_prop, new_prop_size);
 141                 if (!new_prop)
 142                         return -1;
 143
 144                 assoc_arrays = new_prop->value;
 145
 146                 /* increment the number of entries in the lookup array */
 147                 assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);
 148
 149                 /* copy the new associativity into the lookup array */
 150                 index = aa_arrays * aa_array_entries + 2;
 151                 memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);
 152
 153                 of_update_property(dr_node, new_prop);
 154
 155                 /*
 156                  * The associativity lookup array index for this lmb is
 157                  * number of entries - 1 since we added its associativity
 158                  * to the end of the lookup array.
 159                  */
 160                 aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
 161         }
 162
 163         return aa_index;
 164 }
 165
 166 static u32 lookup_lmb_associativity_index(struct drmem_lmb *lmb)
 167 {
 168         struct device_node *parent, *lmb_node, *dr_node;
 169         struct property *ala_prop;
 170         const u32 *lmb_assoc;
 171         u32 aa_index;
 172
 173         parent = of_find_node_by_path("/");
 174         if (!parent)
 175                 return -ENODEV;
 176
 177         lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
 178                                              parent);
 179         of_node_put(parent);
 180         if (!lmb_node)
 181                 return -EINVAL;
 182
 183         lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
 184         if (!lmb_assoc) {
 185                 dlpar_free_cc_nodes(lmb_node);
 186                 return -ENODEV;
 187         }
 188
 189         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 190         if (!dr_node) {
 191                 dlpar_free_cc_nodes(lmb_node);
 192                 return -ENODEV;
 193         }
 194
 195         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
 196                                     NULL);
 197         if (!ala_prop) {
 198                 of_node_put(dr_node);
 199                 dlpar_free_cc_nodes(lmb_node);
 200                 return -ENODEV;
 201         }
 202
 203         aa_index = find_aa_index(dr_node, ala_prop, lmb_assoc);
 204
 205         dlpar_free_cc_nodes(lmb_node);
 206         return aa_index;
 207 }
 208
 209 static int dlpar_add_device_tree_lmb(struct drmem_lmb *lmb)
 210 {
 211         int rc, aa_index;
 212
 213         lmb->flags |= DRCONF_MEM_ASSIGNED;
 214
 215         aa_index = lookup_lmb_associativity_index(lmb);
 216         if (aa_index < 0) {
 217                 pr_err("Couldn't find associativity index for drc index %x\n",
 218                        lmb->drc_index);
 219                 return aa_index;
 220         }
 221
 222         lmb->aa_index = aa_index;
 223
 224         rtas_hp_event = true;
 225         rc = drmem_update_dt();
 226         rtas_hp_event = false;
 227
 228         return rc;
 229 }
 230
 231 static int dlpar_remove_device_tree_lmb(struct drmem_lmb *lmb)
 232 {
 233         int rc;
 234
 235         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 236         lmb->aa_index = 0xffffffff;
 237
 238         rtas_hp_event = true;
 239         rc = drmem_update_dt();
 240         rtas_hp_event = false;
 241
 242         return rc;
 243 }
 244
 245 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 246 {
 247         unsigned long section_nr;
 248         struct mem_section *mem_sect;
 249         struct memory_block *mem_block;
 250
 251         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 252         mem_sect = __nr_to_section(section_nr);
 253
 254         mem_block = find_memory_block(mem_sect);
 255         return mem_block;
 256 }
 257
 258 static int get_lmb_range(u32 drc_index, int n_lmbs,
 259                          struct drmem_lmb **start_lmb,
 260                          struct drmem_lmb **end_lmb)
 261 {
 262         struct drmem_lmb *lmb, *start, *end;
 263         struct drmem_lmb *last_lmb;
 264
 265         start = NULL;
 266         for_each_drmem_lmb(lmb) {
 267                 if (lmb->drc_index == drc_index) {
 268                         start = lmb;
 269                         break;
 270                 }
 271         }
 272
 273         if (!start)
 274                 return -EINVAL;
 275
 276         end = &start[n_lmbs - 1];
 277
 278         last_lmb = &drmem_info->lmbs[drmem_info->n_lmbs - 1];
 279         if (end > last_lmb)
 280                 return -EINVAL;
 281
 282         *start_lmb = start;
 283         *end_lmb = end;
 284         return 0;
 285 }
 286
 287 static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
 288 {
 289         struct memory_block *mem_block;
 290         int rc;
 291
 292         mem_block = lmb_to_memblock(lmb);
 293         if (!mem_block)
 294                 return -EINVAL;
 295
 296         if (online && mem_block->dev.offline)
 297                 rc = device_online(&mem_block->dev);
 298         else if (!online && !mem_block->dev.offline)
 299                 rc = device_offline(&mem_block->dev);
 300         else
 301                 rc = 0;
 302
 303         put_device(&mem_block->dev);
 304
 305         return rc;
 306 }
 307
 308 static int dlpar_online_lmb(struct drmem_lmb *lmb)
 309 {
 310         return dlpar_change_lmb_state(lmb, true);
 311 }
 312
 313 #ifdef CONFIG_MEMORY_HOTREMOVE
 314 static int dlpar_offline_lmb(struct drmem_lmb *lmb)
 315 {
 316         return dlpar_change_lmb_state(lmb, false);
 317 }
 318
 319 static int pseries_remove_memblock(unsigned long base, unsigned int memblock_size)
 320 {
 321         unsigned long block_sz, start_pfn;
 322         int sections_per_block;
 323         int i, nid;
 324
 325         start_pfn = base >> PAGE_SHIFT;
 326
 327         lock_device_hotplug();
 328
 329         if (!pfn_valid(start_pfn))
 330                 goto out;
 331
 332         block_sz = pseries_memory_block_size();
 333         sections_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 334         nid = memory_add_physaddr_to_nid(base);
 335
 336         for (i = 0; i < sections_per_block; i++) {
 337                 remove_memory(nid, base, MIN_MEMORY_BLOCK_SIZE);
 338                 base += MIN_MEMORY_BLOCK_SIZE;
 339         }
 340
 341 out:
 342         /* Update memory regions for memory remove */
 343         memblock_remove(base, memblock_size);
 344         unlock_device_hotplug();
 345         return 0;
 346 }
 347
 348 static int pseries_remove_mem_node(struct device_node *np)
 349 {
 350         const char *type;
 351         const __be32 *regs;
 352         unsigned long base;
 353         unsigned int lmb_size;
 354         int ret = -EINVAL;
 355
 356         /*
 357          * Check to see if we are actually removing memory
 358          */
 359         type = of_get_property(np, "device_type", NULL);
 360         if (type == NULL || strcmp(type, "memory") != 0)
 361                 return 0;
 362
 363         /*
 364          * Find the base address and size of the memblock
 365          */
 366         regs = of_get_property(np, "reg", NULL);
 367         if (!regs)
 368                 return ret;
 369
 370         base = be64_to_cpu(*(unsigned long *)regs);
 371         lmb_size = be32_to_cpu(regs[3]);
 372
 373         pseries_remove_memblock(base, lmb_size);
 374         return 0;
 375 }
 376
 377 static bool lmb_is_removable(struct drmem_lmb *lmb)
 378 {
 379         int i, scns_per_block;
 380         int rc = 1;
 381         unsigned long pfn, block_sz;
 382         u64 phys_addr;
 383
 384         if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 385                 return false;
 386
 387         block_sz = memory_block_size_bytes();
 388         scns_per_block = block_sz / MIN_MEMORY_BLOCK_SIZE;
 389         phys_addr = lmb->base_addr;
 390
 391 #ifdef CONFIG_FA_DUMP
 392         /* Don't hot-remove memory that falls in fadump boot memory area */
 393         if (is_fadump_boot_memory_area(phys_addr, block_sz))
 394                 return false;
 395 #endif
 396
 397         for (i = 0; i < scns_per_block; i++) {
 398                 pfn = PFN_DOWN(phys_addr);
 399                 if (!pfn_present(pfn))
 400                         continue;
 401
 402                 rc &= is_mem_section_removable(pfn, PAGES_PER_SECTION);
 403                 phys_addr += MIN_MEMORY_BLOCK_SIZE;
 404         }
 405
 406         return rc ? true : false;
 407 }
 408
 409 static int dlpar_add_lmb(struct drmem_lmb *);
 410
 411 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 412 {
 413         unsigned long block_sz;
 414         int nid, rc;
 415
 416         if (!lmb_is_removable(lmb))
 417                 return -EINVAL;
 418
 419         rc = dlpar_offline_lmb(lmb);
 420         if (rc)
 421                 return rc;
 422
 423         block_sz = pseries_memory_block_size();
 424         nid = memory_add_physaddr_to_nid(lmb->base_addr);
 425
 426         remove_memory(nid, lmb->base_addr, block_sz);
 427
 428         /* Update memory regions for memory remove */
 429         memblock_remove(lmb->base_addr, block_sz);
 430
 431         dlpar_remove_device_tree_lmb(lmb);
 432         return 0;
 433 }
 434
 435 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 436 {
 437         struct drmem_lmb *lmb;
 438         int lmbs_removed = 0;
 439         int lmbs_available = 0;
 440         int rc;
 441
 442         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 443
 444         if (lmbs_to_remove == 0)
 445                 return -EINVAL;
 446
 447         /* Validate that there are enough LMBs to satisfy the request */
 448         for_each_drmem_lmb(lmb) {
 449                 if (lmb_is_removable(lmb))
 450                         lmbs_available++;
 451
 452                 if (lmbs_available == lmbs_to_remove)
 453                         break;
 454         }
 455
 456         if (lmbs_available < lmbs_to_remove) {
 457                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 458                         lmbs_available, lmbs_to_remove);
 459                 return -EINVAL;
 460         }
 461
 462         for_each_drmem_lmb(lmb) {
 463                 rc = dlpar_remove_lmb(lmb);
 464                 if (rc)
 465                         continue;
 466
 467                 /* Mark this lmb so we can add it later if all of the
 468                  * requested LMBs cannot be removed.
 469                  */
 470                 drmem_mark_lmb_reserved(lmb);
 471
 472                 lmbs_removed++;
 473                 if (lmbs_removed == lmbs_to_remove)
 474                         break;
 475         }
 476
 477         if (lmbs_removed != lmbs_to_remove) {
 478                 pr_err("Memory hot-remove failed, adding LMB's back\n");
 479
 480                 for_each_drmem_lmb(lmb) {
 481                         if (!drmem_lmb_reserved(lmb))
 482                                 continue;
 483
 484                         rc = dlpar_add_lmb(lmb);
 485                         if (rc)
 486                                 pr_err("Failed to add LMB back, drc index %x\n",
 487                                        lmb->drc_index);
 488
 489                         drmem_remove_lmb_reservation(lmb);
 490                 }
 491
 492                 rc = -EINVAL;
 493         } else {
 494                 for_each_drmem_lmb(lmb) {
 495                         if (!drmem_lmb_reserved(lmb))
 496                                 continue;
 497
 498                         dlpar_release_drc(lmb->drc_index);
 499                         pr_info("Memory at %llx was hot-removed\n",
 500                                 lmb->base_addr);
 501
 502                         drmem_remove_lmb_reservation(lmb);
 503                 }
 504                 rc = 0;
 505         }
 506
 507         return rc;
 508 }
 509
 510 static int dlpar_memory_remove_by_index(u32 drc_index)
 511 {
 512         struct drmem_lmb *lmb;
 513         int lmb_found;
 514         int rc;
 515
 516         pr_info("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 517
 518         lmb_found = 0;
 519         for_each_drmem_lmb(lmb) {
 520                 if (lmb->drc_index == drc_index) {
 521                         lmb_found = 1;
 522                         rc = dlpar_remove_lmb(lmb);
 523                         if (!rc)
 524                                 dlpar_release_drc(lmb->drc_index);
 525
 526                         break;
 527                 }
 528         }
 529
 530         if (!lmb_found)
 531                 rc = -EINVAL;
 532
 533         if (rc)
 534                 pr_info("Failed to hot-remove memory at %llx\n",
 535                         lmb->base_addr);
 536         else
 537                 pr_info("Memory at %llx was hot-removed\n", lmb->base_addr);
 538
 539         return rc;
 540 }
 541
 542 static int dlpar_memory_readd_by_index(u32 drc_index)
 543 {
 544         struct drmem_lmb *lmb;
 545         int lmb_found;
 546         int rc;
 547
 548         pr_info("Attempting to update LMB, drc index %x\n", drc_index);
 549
 550         lmb_found = 0;
 551         for_each_drmem_lmb(lmb) {
 552                 if (lmb->drc_index == drc_index) {
 553                         lmb_found = 1;
 554                         rc = dlpar_remove_lmb(lmb);
 555                         if (!rc) {
 556                                 rc = dlpar_add_lmb(lmb);
 557                                 if (rc)
 558                                         dlpar_release_drc(lmb->drc_index);
 559                         }
 560                         break;
 561                 }
 562         }
 563
 564         if (!lmb_found)
 565                 rc = -EINVAL;
 566
 567         if (rc)
 568                 pr_info("Failed to update memory at %llx\n",
 569                         lmb->base_addr);
 570         else
 571                 pr_info("Memory at %llx was updated\n", lmb->base_addr);
 572
 573         return rc;
 574 }
 575
 576 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 577 {
 578         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 579         int lmbs_available = 0;
 580         int rc;
 581
 582         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 583                 lmbs_to_remove, drc_index);
 584
 585         if (lmbs_to_remove == 0)
 586                 return -EINVAL;
 587
 588         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 589         if (rc)
 590                 return -EINVAL;
 591
 592         /* Validate that there are enough LMBs to satisfy the request */
 593         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 594                 if (lmb->flags & DRCONF_MEM_RESERVED)
 595                         break;
 596
 597                 lmbs_available++;
 598         }
 599
 600         if (lmbs_available < lmbs_to_remove)
 601                 return -EINVAL;
 602
 603         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 604                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 605                         continue;
 606
 607                 rc = dlpar_remove_lmb(lmb);
 608                 if (rc)
 609                         break;
 610
 611                 drmem_mark_lmb_reserved(lmb);
 612         }
 613
 614         if (rc) {
 615                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 616
 617
 618                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 619                         if (!drmem_lmb_reserved(lmb))
 620                                 continue;
 621
 622                         rc = dlpar_add_lmb(lmb);
 623                         if (rc)
 624                                 pr_err("Failed to add LMB, drc index %x\n",
 625                                        lmb->drc_index);
 626
 627                         drmem_remove_lmb_reservation(lmb);
 628                 }
 629                 rc = -EINVAL;
 630         } else {
 631                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 632                         if (!drmem_lmb_reserved(lmb))
 633                                 continue;
 634
 635                         dlpar_release_drc(lmb->drc_index);
 636                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 637                                 lmb->base_addr, lmb->drc_index);
 638
 639                         drmem_remove_lmb_reservation(lmb);
 640                 }
 641         }
 642
 643         return rc;
 644 }
 645
 646 #else
 647 static inline int pseries_remove_memblock(unsigned long base,
 648                                           unsigned int memblock_size)
 649 {
 650         return -EOPNOTSUPP;
 651 }
 652 static inline int pseries_remove_mem_node(struct device_node *np)
 653 {
 654         return 0;
 655 }
 656 static inline int dlpar_memory_remove(struct pseries_hp_errorlog *hp_elog)
 657 {
 658         return -EOPNOTSUPP;
 659 }
 660 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 661 {
 662         return -EOPNOTSUPP;
 663 }
 664 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 665 {
 666         return -EOPNOTSUPP;
 667 }
 668 static int dlpar_memory_remove_by_index(u32 drc_index)
 669 {
 670         return -EOPNOTSUPP;
 671 }
 672 static int dlpar_memory_readd_by_index(u32 drc_index)
 673 {
 674         return -EOPNOTSUPP;
 675 }
 676
 677 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 678 {
 679         return -EOPNOTSUPP;
 680 }
 681 #endif /* CONFIG_MEMORY_HOTREMOVE */
 682
 683 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 684 {
 685         unsigned long block_sz;
 686         int nid, rc;
 687
 688         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 689                 return -EINVAL;
 690
 691         rc = dlpar_add_device_tree_lmb(lmb);
 692         if (rc) {
 693                 pr_err("Couldn't update device tree for drc index %x\n",
 694                        lmb->drc_index);
 695                 dlpar_release_drc(lmb->drc_index);
 696                 return rc;
 697         }
 698
 699         block_sz = memory_block_size_bytes();
 700
 701         /* Find the node id for this address */
 702         nid = memory_add_physaddr_to_nid(lmb->base_addr);
 703
 704         /* Add the memory */
 705         rc = add_memory(nid, lmb->base_addr, block_sz);
 706         if (rc) {
 707                 dlpar_remove_device_tree_lmb(lmb);
 708                 return rc;
 709         }
 710
 711         rc = dlpar_online_lmb(lmb);
 712         if (rc) {
 713                 remove_memory(nid, lmb->base_addr, block_sz);
 714                 dlpar_remove_device_tree_lmb(lmb);
 715         } else {
 716                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 717         }
 718
 719         return rc;
 720 }
 721
 722 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 723 {
 724         struct drmem_lmb *lmb;
 725         int lmbs_available = 0;
 726         int lmbs_added = 0;
 727         int rc;
 728
 729         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 730
 731         if (lmbs_to_add == 0)
 732                 return -EINVAL;
 733
 734         /* Validate that there are enough LMBs to satisfy the request */
 735         for_each_drmem_lmb(lmb) {
 736                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 737                         lmbs_available++;
 738
 739                 if (lmbs_available == lmbs_to_add)
 740                         break;
 741         }
 742
 743         if (lmbs_available < lmbs_to_add)
 744                 return -EINVAL;
 745
 746         for_each_drmem_lmb(lmb) {
 747                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 748                         continue;
 749
 750                 rc = dlpar_acquire_drc(lmb->drc_index);
 751                 if (rc)
 752                         continue;
 753
 754                 rc = dlpar_add_lmb(lmb);
 755                 if (rc) {
 756                         dlpar_release_drc(lmb->drc_index);
 757                         continue;
 758                 }
 759
 760                 /* Mark this lmb so we can remove it later if all of the
 761                  * requested LMBs cannot be added.
 762                  */
 763                 drmem_mark_lmb_reserved(lmb);
 764
 765                 lmbs_added++;
 766                 if (lmbs_added == lmbs_to_add)
 767                         break;
 768         }
 769
 770         if (lmbs_added != lmbs_to_add) {
 771                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 772
 773                 for_each_drmem_lmb(lmb) {
 774                         if (!drmem_lmb_reserved(lmb))
 775                                 continue;
 776
 777                         rc = dlpar_remove_lmb(lmb);
 778                         if (rc)
 779                                 pr_err("Failed to remove LMB, drc index %x\n",
 780                                        lmb->drc_index);
 781                         else
 782                                 dlpar_release_drc(lmb->drc_index);
 783
 784                         drmem_remove_lmb_reservation(lmb);
 785                 }
 786                 rc = -EINVAL;
 787         } else {
 788                 for_each_drmem_lmb(lmb) {
 789                         if (!drmem_lmb_reserved(lmb))
 790                                 continue;
 791
 792                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 793                                 lmb->base_addr, lmb->drc_index);
 794                         drmem_remove_lmb_reservation(lmb);
 795                 }
 796                 rc = 0;
 797         }
 798
 799         return rc;
 800 }
 801
 802 static int dlpar_memory_add_by_index(u32 drc_index)
 803 {
 804         struct drmem_lmb *lmb;
 805         int rc, lmb_found;
 806
 807         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 808
 809         lmb_found = 0;
 810         for_each_drmem_lmb(lmb) {
 811                 if (lmb->drc_index == drc_index) {
 812                         lmb_found = 1;
 813                         rc = dlpar_acquire_drc(lmb->drc_index);
 814                         if (!rc) {
 815                                 rc = dlpar_add_lmb(lmb);
 816                                 if (rc)
 817                                         dlpar_release_drc(lmb->drc_index);
 818                         }
 819
 820                         break;
 821                 }
 822         }
 823
 824         if (!lmb_found)
 825                 rc = -EINVAL;
 826
 827         if (rc)
 828                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 829         else
 830                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 831                         lmb->base_addr, drc_index);
 832
 833         return rc;
 834 }
 835
 836 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 837 {
 838         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 839         int lmbs_available = 0;
 840         int rc;
 841
 842         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 843                 lmbs_to_add, drc_index);
 844
 845         if (lmbs_to_add == 0)
 846                 return -EINVAL;
 847
 848         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 849         if (rc)
 850                 return -EINVAL;
 851
 852         /* Validate that the LMBs in this range are not reserved */
 853         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 854                 if (lmb->flags & DRCONF_MEM_RESERVED)
 855                         break;
 856
 857                 lmbs_available++;
 858         }
 859
 860         if (lmbs_available < lmbs_to_add)
 861                 return -EINVAL;
 862
 863         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 864                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 865                         continue;
 866
 867                 rc = dlpar_acquire_drc(lmb->drc_index);
 868                 if (rc)
 869                         break;
 870
 871                 rc = dlpar_add_lmb(lmb);
 872                 if (rc) {
 873                         dlpar_release_drc(lmb->drc_index);
 874                         break;
 875                 }
 876
 877                 drmem_mark_lmb_reserved(lmb);
 878         }
 879
 880         if (rc) {
 881                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 882
 883                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 884                         if (!drmem_lmb_reserved(lmb))
 885                                 continue;
 886
 887                         rc = dlpar_remove_lmb(lmb);
 888                         if (rc)
 889                                 pr_err("Failed to remove LMB, drc index %x\n",
 890                                        lmb->drc_index);
 891                         else
 892                                 dlpar_release_drc(lmb->drc_index);
 893
 894                         drmem_remove_lmb_reservation(lmb);
 895                 }
 896                 rc = -EINVAL;
 897         } else {
 898                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 899                         if (!drmem_lmb_reserved(lmb))
 900                                 continue;
 901
 902                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 903                                 lmb->base_addr, lmb->drc_index);
 904                         drmem_remove_lmb_reservation(lmb);
 905                 }
 906         }
 907
 908         return rc;
 909 }
 910
 911 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 912 {
 913         u32 count, drc_index;
 914         int rc;
 915
 916         lock_device_hotplug();
 917
 918         switch (hp_elog->action) {
 919         case PSERIES_HP_ELOG_ACTION_ADD:
 920                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
 921                         count = hp_elog->_drc_u.drc_count;
 922                         rc = dlpar_memory_add_by_count(count);
 923                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
 924                         drc_index = hp_elog->_drc_u.drc_index;
 925                         rc = dlpar_memory_add_by_index(drc_index);
 926                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
 927                         count = hp_elog->_drc_u.ic.count;
 928                         drc_index = hp_elog->_drc_u.ic.index;
 929                         rc = dlpar_memory_add_by_ic(count, drc_index);
 930                 } else {
 931                         rc = -EINVAL;
 932                 }
 933
 934                 break;
 935         case PSERIES_HP_ELOG_ACTION_REMOVE:
 936                 if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_COUNT) {
 937                         count = hp_elog->_drc_u.drc_count;
 938                         rc = dlpar_memory_remove_by_count(count);
 939                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_INDEX) {
 940                         drc_index = hp_elog->_drc_u.drc_index;
 941                         rc = dlpar_memory_remove_by_index(drc_index);
 942                 } else if (hp_elog->id_type == PSERIES_HP_ELOG_ID_DRC_IC) {
 943                         count = hp_elog->_drc_u.ic.count;
 944                         drc_index = hp_elog->_drc_u.ic.index;
 945                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 946                 } else {
 947                         rc = -EINVAL;
 948                 }
 949
 950                 break;
 951         case PSERIES_HP_ELOG_ACTION_READD:
 952                 drc_index = hp_elog->_drc_u.drc_index;
 953                 rc = dlpar_memory_readd_by_index(drc_index);
 954                 break;
 955         default:
 956                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 957                 rc = -EINVAL;
 958                 break;
 959         }
 960
 961         unlock_device_hotplug();
 962         return rc;
 963 }
 964
 965 static int pseries_add_mem_node(struct device_node *np)
 966 {
 967         const char *type;
 968         const __be32 *regs;
 969         unsigned long base;
 970         unsigned int lmb_size;
 971         int ret = -EINVAL;
 972
 973         /*
 974          * Check to see if we are actually adding memory
 975          */
 976         type = of_get_property(np, "device_type", NULL);
 977         if (type == NULL || strcmp(type, "memory") != 0)
 978                 return 0;
 979
 980         /*
 981          * Find the base and size of the memblock
 982          */
 983         regs = of_get_property(np, "reg", NULL);
 984         if (!regs)
 985                 return ret;
 986
 987         base = be64_to_cpu(*(unsigned long *)regs);
 988         lmb_size = be32_to_cpu(regs[3]);
 989
 990         /*
 991          * Update memory region to represent the memory add
 992          */
 993         ret = memblock_add(base, lmb_size);
 994         return (ret < 0) ? -EINVAL : 0;
 995 }
 996
 997 static int pseries_update_drconf_memory(struct of_reconfig_data *pr)
 998 {
 999         struct of_drconf_cell_v1 *new_drmem, *old_drmem;
1000         unsigned long memblock_size;
1001         u32 entries;
1002         __be32 *p;
1003         int i, rc = -EINVAL;
1004
1005         if (rtas_hp_event)
1006                 return 0;
1007
1008         memblock_size = pseries_memory_block_size();
1009         if (!memblock_size)
1010                 return -EINVAL;
1011
1012         p = (__be32 *) pr->old_prop->value;
1013         if (!p)
1014                 return -EINVAL;
1015
1016         /* The first int of the property is the number of lmb's described
1017          * by the property. This is followed by an array of of_drconf_cell
1018          * entries. Get the number of entries and skip to the array of
1019          * of_drconf_cell's.
1020          */
1021         entries = be32_to_cpu(*p++);
1022         old_drmem = (struct of_drconf_cell_v1 *)p;
1023
1024         p = (__be32 *)pr->prop->value;
1025         p++;
1026         new_drmem = (struct of_drconf_cell_v1 *)p;
1027
1028         for (i = 0; i < entries; i++) {
1029                 if ((be32_to_cpu(old_drmem[i].flags) & DRCONF_MEM_ASSIGNED) &&
1030                     (!(be32_to_cpu(new_drmem[i].flags) & DRCONF_MEM_ASSIGNED))) {
1031                         rc = pseries_remove_memblock(
1032                                 be64_to_cpu(old_drmem[i].base_addr),
1033                                                      memblock_size);
1034                         break;
1035                 } else if ((!(be32_to_cpu(old_drmem[i].flags) &
1036                             DRCONF_MEM_ASSIGNED)) &&
1037                             (be32_to_cpu(new_drmem[i].flags) &
1038                             DRCONF_MEM_ASSIGNED)) {
1039                         rc = memblock_add(be64_to_cpu(old_drmem[i].base_addr),
1040                                           memblock_size);
1041                         rc = (rc < 0) ? -EINVAL : 0;
1042                         break;
1043                 }
1044         }
1045         return rc;
1046 }
1047
1048 static int pseries_memory_notifier(struct notifier_block *nb,
1049                                    unsigned long action, void *data)
1050 {
1051         struct of_reconfig_data *rd = data;
1052         int err = 0;
1053
1054         switch (action) {
1055         case OF_RECONFIG_ATTACH_NODE:
1056                 err = pseries_add_mem_node(rd->dn);
1057                 break;
1058         case OF_RECONFIG_DETACH_NODE:
1059                 err = pseries_remove_mem_node(rd->dn);
1060                 break;
1061         case OF_RECONFIG_UPDATE_PROPERTY:
1062                 if (!strcmp(rd->prop->name, "ibm,dynamic-memory"))
1063                         err = pseries_update_drconf_memory(rd);
1064                 break;
1065         }
1066         return notifier_from_errno(err);
1067 }
1068
1069 static struct notifier_block pseries_mem_nb = {
1070         .notifier_call = pseries_memory_notifier,
1071 };
1072
1073 static int __init pseries_memory_hotplug_init(void)
1074 {
1075         if (firmware_has_feature(FW_FEATURE_LPAR))
1076                 of_reconfig_notifier_register(&pseries_mem_nb);
1077
1078         return 0;
1079 }
1080 machine_device_initcall(pseries, pseries_memory_hotplug_init);