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

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * pseries Memory Hotplug infrastructure.
   4  *
   5  * Copyright (C) 2008 Badari Pulavarty, IBM Corporation
   6  */
   7
   8 #define pr_fmt(fmt)     "pseries-hotplug-mem: " fmt
   9
  10 #include <linux/of.h>
  11 #include <linux/of_address.h>
  12 #include <linux/memblock.h>
  13 #include <linux/memory.h>
  14 #include <linux/memory_hotplug.h>
  15 #include <linux/slab.h>
  16
  17 #include <asm/firmware.h>
  18 #include <asm/machdep.h>
  19 #include <asm/prom.h>
  20 #include <asm/sparsemem.h>
  21 #include <asm/fadump.h>
  22 #include <asm/drmem.h>
  23 #include "pseries.h"
  24
  25 unsigned long pseries_memory_block_size(void)
  26 {
  27         struct device_node *np;
  28         u64 memblock_size = MIN_MEMORY_BLOCK_SIZE;
  29         struct resource r;
  30
  31         np = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
  32         if (np) {
  33                 int len;
  34                 int size_cells;
  35                 const __be32 *prop;
  36
  37                 size_cells = of_n_size_cells(np);
  38
  39                 prop = of_get_property(np, "ibm,lmb-size", &len);
  40                 if (prop && len >= size_cells * sizeof(__be32))
  41                         memblock_size = of_read_number(prop, size_cells);
  42                 of_node_put(np);
  43
  44         } else  if (machine_is(pseries)) {
  45                 /* This fallback really only applies to pseries */
  46                 unsigned int memzero_size = 0;
  47
  48                 np = of_find_node_by_path("/memory@0");
  49                 if (np) {
  50                         if (!of_address_to_resource(np, 0, &r))
  51                                 memzero_size = resource_size(&r);
  52                         of_node_put(np);
  53                 }
  54
  55                 if (memzero_size) {
  56                         /* We now know the size of memory@0, use this to find
  57                          * the first memoryblock and get its size.
  58                          */
  59                         char buf[64];
  60
  61                         sprintf(buf, "/memory@%x", memzero_size);
  62                         np = of_find_node_by_path(buf);
  63                         if (np) {
  64                                 if (!of_address_to_resource(np, 0, &r))
  65                                         memblock_size = resource_size(&r);
  66                                 of_node_put(np);
  67                         }
  68                 }
  69         }
  70         return memblock_size;
  71 }
  72
  73 static void dlpar_free_property(struct property *prop)
  74 {
  75         kfree(prop->name);
  76         kfree(prop->value);
  77         kfree(prop);
  78 }
  79
  80 static struct property *dlpar_clone_property(struct property *prop,
  81                                              u32 prop_size)
  82 {
  83         struct property *new_prop;
  84
  85         new_prop = kzalloc(sizeof(*new_prop), GFP_KERNEL);
  86         if (!new_prop)
  87                 return NULL;
  88
  89         new_prop->name = kstrdup(prop->name, GFP_KERNEL);
  90         new_prop->value = kzalloc(prop_size, GFP_KERNEL);
  91         if (!new_prop->name || !new_prop->value) {
  92                 dlpar_free_property(new_prop);
  93                 return NULL;
  94         }
  95
  96         memcpy(new_prop->value, prop->value, prop->length);
  97         new_prop->length = prop_size;
  98
  99         of_property_set_flag(new_prop, OF_DYNAMIC);
 100         return new_prop;
 101 }
 102
 103 static bool find_aa_index(struct device_node *dr_node,
 104                          struct property *ala_prop,
 105                          const u32 *lmb_assoc, u32 *aa_index)
 106 {
 107         u32 *assoc_arrays, new_prop_size;
 108         struct property *new_prop;
 109         int aa_arrays, aa_array_entries, aa_array_sz;
 110         int i, index;
 111
 112         /*
 113          * The ibm,associativity-lookup-arrays property is defined to be
 114          * a 32-bit value specifying the number of associativity arrays
 115          * followed by a 32-bitvalue specifying the number of entries per
 116          * array, followed by the associativity arrays.
 117          */
 118         assoc_arrays = ala_prop->value;
 119
 120         aa_arrays = be32_to_cpu(assoc_arrays[0]);
 121         aa_array_entries = be32_to_cpu(assoc_arrays[1]);
 122         aa_array_sz = aa_array_entries * sizeof(u32);
 123
 124         for (i = 0; i < aa_arrays; i++) {
 125                 index = (i * aa_array_entries) + 2;
 126
 127                 if (memcmp(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz))
 128                         continue;
 129
 130                 *aa_index = i;
 131                 return true;
 132         }
 133
 134         new_prop_size = ala_prop->length + aa_array_sz;
 135         new_prop = dlpar_clone_property(ala_prop, new_prop_size);
 136         if (!new_prop)
 137                 return false;
 138
 139         assoc_arrays = new_prop->value;
 140
 141         /* increment the number of entries in the lookup array */
 142         assoc_arrays[0] = cpu_to_be32(aa_arrays + 1);
 143
 144         /* copy the new associativity into the lookup array */
 145         index = aa_arrays * aa_array_entries + 2;
 146         memcpy(&assoc_arrays[index], &lmb_assoc[1], aa_array_sz);
 147
 148         of_update_property(dr_node, new_prop);
 149
 150         /*
 151          * The associativity lookup array index for this lmb is
 152          * number of entries - 1 since we added its associativity
 153          * to the end of the lookup array.
 154          */
 155         *aa_index = be32_to_cpu(assoc_arrays[0]) - 1;
 156         return true;
 157 }
 158
 159 static int update_lmb_associativity_index(struct drmem_lmb *lmb)
 160 {
 161         struct device_node *parent, *lmb_node, *dr_node;
 162         struct property *ala_prop;
 163         const u32 *lmb_assoc;
 164         u32 aa_index;
 165         bool found;
 166
 167         parent = of_find_node_by_path("/");
 168         if (!parent)
 169                 return -ENODEV;
 170
 171         lmb_node = dlpar_configure_connector(cpu_to_be32(lmb->drc_index),
 172                                              parent);
 173         of_node_put(parent);
 174         if (!lmb_node)
 175                 return -EINVAL;
 176
 177         lmb_assoc = of_get_property(lmb_node, "ibm,associativity", NULL);
 178         if (!lmb_assoc) {
 179                 dlpar_free_cc_nodes(lmb_node);
 180                 return -ENODEV;
 181         }
 182
 183         update_numa_distance(lmb_node);
 184
 185         dr_node = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 186         if (!dr_node) {
 187                 dlpar_free_cc_nodes(lmb_node);
 188                 return -ENODEV;
 189         }
 190
 191         ala_prop = of_find_property(dr_node, "ibm,associativity-lookup-arrays",
 192                                     NULL);
 193         if (!ala_prop) {
 194                 of_node_put(dr_node);
 195                 dlpar_free_cc_nodes(lmb_node);
 196                 return -ENODEV;
 197         }
 198
 199         found = find_aa_index(dr_node, ala_prop, lmb_assoc, &aa_index);
 200
 201         of_node_put(dr_node);
 202         dlpar_free_cc_nodes(lmb_node);
 203
 204         if (!found) {
 205                 pr_err("Could not find LMB associativity\n");
 206                 return -1;
 207         }
 208
 209         lmb->aa_index = aa_index;
 210         return 0;
 211 }
 212
 213 static struct memory_block *lmb_to_memblock(struct drmem_lmb *lmb)
 214 {
 215         unsigned long section_nr;
 216         struct memory_block *mem_block;
 217
 218         section_nr = pfn_to_section_nr(PFN_DOWN(lmb->base_addr));
 219
 220         mem_block = find_memory_block(section_nr);
 221         return mem_block;
 222 }
 223
 224 static int get_lmb_range(u32 drc_index, int n_lmbs,
 225                          struct drmem_lmb **start_lmb,
 226                          struct drmem_lmb **end_lmb)
 227 {
 228         struct drmem_lmb *lmb, *start, *end;
 229         struct drmem_lmb *limit;
 230
 231         start = NULL;
 232         for_each_drmem_lmb(lmb) {
 233                 if (lmb->drc_index == drc_index) {
 234                         start = lmb;
 235                         break;
 236                 }
 237         }
 238
 239         if (!start)
 240                 return -EINVAL;
 241
 242         end = &start[n_lmbs];
 243
 244         limit = &drmem_info->lmbs[drmem_info->n_lmbs];
 245         if (end > limit)
 246                 return -EINVAL;
 247
 248         *start_lmb = start;
 249         *end_lmb = end;
 250         return 0;
 251 }
 252
 253 static int dlpar_change_lmb_state(struct drmem_lmb *lmb, bool online)
 254 {
 255         struct memory_block *mem_block;
 256         int rc;
 257
 258         mem_block = lmb_to_memblock(lmb);
 259         if (!mem_block)
 260                 return -EINVAL;
 261
 262         if (online && mem_block->dev.offline)
 263                 rc = device_online(&mem_block->dev);
 264         else if (!online && !mem_block->dev.offline)
 265                 rc = device_offline(&mem_block->dev);
 266         else
 267                 rc = 0;
 268
 269         put_device(&mem_block->dev);
 270
 271         return rc;
 272 }
 273
 274 static int dlpar_online_lmb(struct drmem_lmb *lmb)
 275 {
 276         return dlpar_change_lmb_state(lmb, true);
 277 }
 278
 279 #ifdef CONFIG_MEMORY_HOTREMOVE
 280 static int dlpar_offline_lmb(struct drmem_lmb *lmb)
 281 {
 282         return dlpar_change_lmb_state(lmb, false);
 283 }
 284
 285 static int pseries_remove_memblock(unsigned long base, unsigned long memblock_size)
 286 {
 287         unsigned long block_sz, start_pfn;
 288         int sections_per_block;
 289         int i, 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_RESERVED) ||
 352                 !(lmb->flags & DRCONF_MEM_ASSIGNED))
 353                 return false;
 354
 355 #ifdef CONFIG_FA_DUMP
 356         /*
 357          * Don't hot-remove memory that falls in fadump boot memory area
 358          * and memory that is reserved for capturing old kernel memory.
 359          */
 360         if (is_fadump_memory_area(lmb->base_addr, memory_block_size_bytes()))
 361                 return false;
 362 #endif
 363         /* device_offline() will determine if we can actually remove this lmb */
 364         return true;
 365 }
 366
 367 static int dlpar_add_lmb(struct drmem_lmb *);
 368
 369 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 370 {
 371         struct memory_block *mem_block;
 372         unsigned long block_sz;
 373         int rc;
 374
 375         if (!lmb_is_removable(lmb))
 376                 return -EINVAL;
 377
 378         mem_block = lmb_to_memblock(lmb);
 379         if (mem_block == NULL)
 380                 return -EINVAL;
 381
 382         rc = dlpar_offline_lmb(lmb);
 383         if (rc) {
 384                 put_device(&mem_block->dev);
 385                 return rc;
 386         }
 387
 388         block_sz = pseries_memory_block_size();
 389
 390         __remove_memory(mem_block->nid, lmb->base_addr, block_sz);
 391         put_device(&mem_block->dev);
 392
 393         /* Update memory regions for memory remove */
 394         memblock_remove(lmb->base_addr, block_sz);
 395
 396         invalidate_lmb_associativity_index(lmb);
 397         lmb->flags &= ~DRCONF_MEM_ASSIGNED;
 398
 399         return 0;
 400 }
 401
 402 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 403 {
 404         struct drmem_lmb *lmb;
 405         int lmbs_reserved = 0;
 406         int lmbs_available = 0;
 407         int rc;
 408
 409         pr_info("Attempting to hot-remove %d LMB(s)\n", lmbs_to_remove);
 410
 411         if (lmbs_to_remove == 0)
 412                 return -EINVAL;
 413
 414         /* Validate that there are enough LMBs to satisfy the request */
 415         for_each_drmem_lmb(lmb) {
 416                 if (lmb_is_removable(lmb))
 417                         lmbs_available++;
 418
 419                 if (lmbs_available == lmbs_to_remove)
 420                         break;
 421         }
 422
 423         if (lmbs_available < lmbs_to_remove) {
 424                 pr_info("Not enough LMBs available (%d of %d) to satisfy request\n",
 425                         lmbs_available, lmbs_to_remove);
 426                 return -EINVAL;
 427         }
 428
 429         for_each_drmem_lmb(lmb) {
 430                 rc = dlpar_remove_lmb(lmb);
 431                 if (rc)
 432                         continue;
 433
 434                 /* Mark this lmb so we can add it later if all of the
 435                  * requested LMBs cannot be removed.
 436                  */
 437                 drmem_mark_lmb_reserved(lmb);
 438
 439                 lmbs_reserved++;
 440                 if (lmbs_reserved == lmbs_to_remove)
 441                         break;
 442         }
 443
 444         if (lmbs_reserved != lmbs_to_remove) {
 445                 pr_err("Memory hot-remove failed, adding LMB's back\n");
 446
 447                 for_each_drmem_lmb(lmb) {
 448                         if (!drmem_lmb_reserved(lmb))
 449                                 continue;
 450
 451                         rc = dlpar_add_lmb(lmb);
 452                         if (rc)
 453                                 pr_err("Failed to add LMB back, drc index %x\n",
 454                                        lmb->drc_index);
 455
 456                         drmem_remove_lmb_reservation(lmb);
 457
 458                         lmbs_reserved--;
 459                         if (lmbs_reserved == 0)
 460                                 break;
 461                 }
 462
 463                 rc = -EINVAL;
 464         } else {
 465                 for_each_drmem_lmb(lmb) {
 466                         if (!drmem_lmb_reserved(lmb))
 467                                 continue;
 468
 469                         dlpar_release_drc(lmb->drc_index);
 470                         pr_info("Memory at %llx was hot-removed\n",
 471                                 lmb->base_addr);
 472
 473                         drmem_remove_lmb_reservation(lmb);
 474
 475                         lmbs_reserved--;
 476                         if (lmbs_reserved == 0)
 477                                 break;
 478                 }
 479                 rc = 0;
 480         }
 481
 482         return rc;
 483 }
 484
 485 static int dlpar_memory_remove_by_index(u32 drc_index)
 486 {
 487         struct drmem_lmb *lmb;
 488         int lmb_found;
 489         int rc;
 490
 491         pr_debug("Attempting to hot-remove LMB, drc index %x\n", drc_index);
 492
 493         lmb_found = 0;
 494         for_each_drmem_lmb(lmb) {
 495                 if (lmb->drc_index == drc_index) {
 496                         lmb_found = 1;
 497                         rc = dlpar_remove_lmb(lmb);
 498                         if (!rc)
 499                                 dlpar_release_drc(lmb->drc_index);
 500
 501                         break;
 502                 }
 503         }
 504
 505         if (!lmb_found)
 506                 rc = -EINVAL;
 507
 508         if (rc)
 509                 pr_debug("Failed to hot-remove memory at %llx\n",
 510                          lmb->base_addr);
 511         else
 512                 pr_debug("Memory at %llx was hot-removed\n", lmb->base_addr);
 513
 514         return rc;
 515 }
 516
 517 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 518 {
 519         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 520         int rc;
 521
 522         pr_info("Attempting to hot-remove %u LMB(s) at %x\n",
 523                 lmbs_to_remove, drc_index);
 524
 525         if (lmbs_to_remove == 0)
 526                 return -EINVAL;
 527
 528         rc = get_lmb_range(drc_index, lmbs_to_remove, &start_lmb, &end_lmb);
 529         if (rc)
 530                 return -EINVAL;
 531
 532         /*
 533          * Validate that all LMBs in range are not reserved. Note that it
 534          * is ok if they are !ASSIGNED since our goal here is to remove the
 535          * LMB range, regardless of whether some LMBs were already removed
 536          * by any other reason.
 537          *
 538          * This is a contrast to what is done in remove_by_count() where we
 539          * check for both RESERVED and !ASSIGNED (via lmb_is_removable()),
 540          * because we want to remove a fixed amount of LMBs in that function.
 541          */
 542         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 543                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 544                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 545                                 lmb->base_addr, lmb->drc_index);
 546                         return -EINVAL;
 547                 }
 548         }
 549
 550         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 551                 /*
 552                  * dlpar_remove_lmb() will error out if the LMB is already
 553                  * !ASSIGNED, but this case is a no-op for us.
 554                  */
 555                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 556                         continue;
 557
 558                 rc = dlpar_remove_lmb(lmb);
 559                 if (rc)
 560                         break;
 561
 562                 drmem_mark_lmb_reserved(lmb);
 563         }
 564
 565         if (rc) {
 566                 pr_err("Memory indexed-count-remove failed, adding any removed LMBs\n");
 567
 568
 569                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 570                         if (!drmem_lmb_reserved(lmb))
 571                                 continue;
 572
 573                         /*
 574                          * Setting the isolation state of an UNISOLATED/CONFIGURED
 575                          * device to UNISOLATE is a no-op, but the hypervisor can
 576                          * use it as a hint that the LMB removal failed.
 577                          */
 578                         dlpar_unisolate_drc(lmb->drc_index);
 579
 580                         rc = dlpar_add_lmb(lmb);
 581                         if (rc)
 582                                 pr_err("Failed to add LMB, drc index %x\n",
 583                                        lmb->drc_index);
 584
 585                         drmem_remove_lmb_reservation(lmb);
 586                 }
 587                 rc = -EINVAL;
 588         } else {
 589                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 590                         if (!drmem_lmb_reserved(lmb))
 591                                 continue;
 592
 593                         dlpar_release_drc(lmb->drc_index);
 594                         pr_info("Memory at %llx (drc index %x) was hot-removed\n",
 595                                 lmb->base_addr, lmb->drc_index);
 596
 597                         drmem_remove_lmb_reservation(lmb);
 598                 }
 599         }
 600
 601         return rc;
 602 }
 603
 604 #else
 605 static inline int pseries_remove_memblock(unsigned long base,
 606                                           unsigned long memblock_size)
 607 {
 608         return -EOPNOTSUPP;
 609 }
 610 static inline int pseries_remove_mem_node(struct device_node *np)
 611 {
 612         return 0;
 613 }
 614 static int dlpar_remove_lmb(struct drmem_lmb *lmb)
 615 {
 616         return -EOPNOTSUPP;
 617 }
 618 static int dlpar_memory_remove_by_count(u32 lmbs_to_remove)
 619 {
 620         return -EOPNOTSUPP;
 621 }
 622 static int dlpar_memory_remove_by_index(u32 drc_index)
 623 {
 624         return -EOPNOTSUPP;
 625 }
 626
 627 static int dlpar_memory_remove_by_ic(u32 lmbs_to_remove, u32 drc_index)
 628 {
 629         return -EOPNOTSUPP;
 630 }
 631 #endif /* CONFIG_MEMORY_HOTREMOVE */
 632
 633 static int dlpar_add_lmb(struct drmem_lmb *lmb)
 634 {
 635         unsigned long block_sz;
 636         int nid, rc;
 637
 638         if (lmb->flags & DRCONF_MEM_ASSIGNED)
 639                 return -EINVAL;
 640
 641         rc = update_lmb_associativity_index(lmb);
 642         if (rc) {
 643                 dlpar_release_drc(lmb->drc_index);
 644                 return rc;
 645         }
 646
 647         block_sz = memory_block_size_bytes();
 648
 649         /* Find the node id for this LMB.  Fake one if necessary. */
 650         nid = of_drconf_to_nid_single(lmb);
 651         if (nid < 0 || !node_possible(nid))
 652                 nid = first_online_node;
 653
 654         /* Add the memory */
 655         rc = __add_memory(nid, lmb->base_addr, block_sz, MHP_NONE);
 656         if (rc) {
 657                 invalidate_lmb_associativity_index(lmb);
 658                 return rc;
 659         }
 660
 661         rc = dlpar_online_lmb(lmb);
 662         if (rc) {
 663                 __remove_memory(nid, lmb->base_addr, block_sz);
 664                 invalidate_lmb_associativity_index(lmb);
 665         } else {
 666                 lmb->flags |= DRCONF_MEM_ASSIGNED;
 667         }
 668
 669         return rc;
 670 }
 671
 672 static int dlpar_memory_add_by_count(u32 lmbs_to_add)
 673 {
 674         struct drmem_lmb *lmb;
 675         int lmbs_available = 0;
 676         int lmbs_reserved = 0;
 677         int rc;
 678
 679         pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add);
 680
 681         if (lmbs_to_add == 0)
 682                 return -EINVAL;
 683
 684         /* Validate that there are enough LMBs to satisfy the request */
 685         for_each_drmem_lmb(lmb) {
 686                 if (lmb->flags & DRCONF_MEM_RESERVED)
 687                         continue;
 688
 689                 if (!(lmb->flags & DRCONF_MEM_ASSIGNED))
 690                         lmbs_available++;
 691
 692                 if (lmbs_available == lmbs_to_add)
 693                         break;
 694         }
 695
 696         if (lmbs_available < lmbs_to_add)
 697                 return -EINVAL;
 698
 699         for_each_drmem_lmb(lmb) {
 700                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 701                         continue;
 702
 703                 rc = dlpar_acquire_drc(lmb->drc_index);
 704                 if (rc)
 705                         continue;
 706
 707                 rc = dlpar_add_lmb(lmb);
 708                 if (rc) {
 709                         dlpar_release_drc(lmb->drc_index);
 710                         continue;
 711                 }
 712
 713                 /* Mark this lmb so we can remove it later if all of the
 714                  * requested LMBs cannot be added.
 715                  */
 716                 drmem_mark_lmb_reserved(lmb);
 717                 lmbs_reserved++;
 718                 if (lmbs_reserved == lmbs_to_add)
 719                         break;
 720         }
 721
 722         if (lmbs_reserved != lmbs_to_add) {
 723                 pr_err("Memory hot-add failed, removing any added LMBs\n");
 724
 725                 for_each_drmem_lmb(lmb) {
 726                         if (!drmem_lmb_reserved(lmb))
 727                                 continue;
 728
 729                         rc = dlpar_remove_lmb(lmb);
 730                         if (rc)
 731                                 pr_err("Failed to remove LMB, drc index %x\n",
 732                                        lmb->drc_index);
 733                         else
 734                                 dlpar_release_drc(lmb->drc_index);
 735
 736                         drmem_remove_lmb_reservation(lmb);
 737                         lmbs_reserved--;
 738
 739                         if (lmbs_reserved == 0)
 740                                 break;
 741                 }
 742                 rc = -EINVAL;
 743         } else {
 744                 for_each_drmem_lmb(lmb) {
 745                         if (!drmem_lmb_reserved(lmb))
 746                                 continue;
 747
 748                         pr_debug("Memory at %llx (drc index %x) was hot-added\n",
 749                                  lmb->base_addr, lmb->drc_index);
 750                         drmem_remove_lmb_reservation(lmb);
 751                         lmbs_reserved--;
 752
 753                         if (lmbs_reserved == 0)
 754                                 break;
 755                 }
 756                 rc = 0;
 757         }
 758
 759         return rc;
 760 }
 761
 762 static int dlpar_memory_add_by_index(u32 drc_index)
 763 {
 764         struct drmem_lmb *lmb;
 765         int rc, lmb_found;
 766
 767         pr_info("Attempting to hot-add LMB, drc index %x\n", drc_index);
 768
 769         lmb_found = 0;
 770         for_each_drmem_lmb(lmb) {
 771                 if (lmb->drc_index == drc_index) {
 772                         lmb_found = 1;
 773                         rc = dlpar_acquire_drc(lmb->drc_index);
 774                         if (!rc) {
 775                                 rc = dlpar_add_lmb(lmb);
 776                                 if (rc)
 777                                         dlpar_release_drc(lmb->drc_index);
 778                         }
 779
 780                         break;
 781                 }
 782         }
 783
 784         if (!lmb_found)
 785                 rc = -EINVAL;
 786
 787         if (rc)
 788                 pr_info("Failed to hot-add memory, drc index %x\n", drc_index);
 789         else
 790                 pr_info("Memory at %llx (drc index %x) was hot-added\n",
 791                         lmb->base_addr, drc_index);
 792
 793         return rc;
 794 }
 795
 796 static int dlpar_memory_add_by_ic(u32 lmbs_to_add, u32 drc_index)
 797 {
 798         struct drmem_lmb *lmb, *start_lmb, *end_lmb;
 799         int rc;
 800
 801         pr_info("Attempting to hot-add %u LMB(s) at index %x\n",
 802                 lmbs_to_add, drc_index);
 803
 804         if (lmbs_to_add == 0)
 805                 return -EINVAL;
 806
 807         rc = get_lmb_range(drc_index, lmbs_to_add, &start_lmb, &end_lmb);
 808         if (rc)
 809                 return -EINVAL;
 810
 811         /* Validate that the LMBs in this range are not reserved */
 812         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 813                 /* Fail immediately if the whole range can't be hot-added */
 814                 if (lmb->flags & DRCONF_MEM_RESERVED) {
 815                         pr_err("Memory at %llx (drc index %x) is reserved\n",
 816                                         lmb->base_addr, lmb->drc_index);
 817                         return -EINVAL;
 818                 }
 819         }
 820
 821         for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 822                 if (lmb->flags & DRCONF_MEM_ASSIGNED)
 823                         continue;
 824
 825                 rc = dlpar_acquire_drc(lmb->drc_index);
 826                 if (rc)
 827                         break;
 828
 829                 rc = dlpar_add_lmb(lmb);
 830                 if (rc) {
 831                         dlpar_release_drc(lmb->drc_index);
 832                         break;
 833                 }
 834
 835                 drmem_mark_lmb_reserved(lmb);
 836         }
 837
 838         if (rc) {
 839                 pr_err("Memory indexed-count-add failed, removing any added LMBs\n");
 840
 841                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 842                         if (!drmem_lmb_reserved(lmb))
 843                                 continue;
 844
 845                         rc = dlpar_remove_lmb(lmb);
 846                         if (rc)
 847                                 pr_err("Failed to remove LMB, drc index %x\n",
 848                                        lmb->drc_index);
 849                         else
 850                                 dlpar_release_drc(lmb->drc_index);
 851
 852                         drmem_remove_lmb_reservation(lmb);
 853                 }
 854                 rc = -EINVAL;
 855         } else {
 856                 for_each_drmem_lmb_in_range(lmb, start_lmb, end_lmb) {
 857                         if (!drmem_lmb_reserved(lmb))
 858                                 continue;
 859
 860                         pr_info("Memory at %llx (drc index %x) was hot-added\n",
 861                                 lmb->base_addr, lmb->drc_index);
 862                         drmem_remove_lmb_reservation(lmb);
 863                 }
 864         }
 865
 866         return rc;
 867 }
 868
 869 int dlpar_memory(struct pseries_hp_errorlog *hp_elog)
 870 {
 871         u32 count, drc_index;
 872         int rc;
 873
 874         lock_device_hotplug();
 875
 876         switch (hp_elog->action) {
 877         case PSERIES_HP_ELOG_ACTION_ADD:
 878                 switch (hp_elog->id_type) {
 879                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 880                         count = hp_elog->_drc_u.drc_count;
 881                         rc = dlpar_memory_add_by_count(count);
 882                         break;
 883                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 884                         drc_index = hp_elog->_drc_u.drc_index;
 885                         rc = dlpar_memory_add_by_index(drc_index);
 886                         break;
 887                 case PSERIES_HP_ELOG_ID_DRC_IC:
 888                         count = hp_elog->_drc_u.ic.count;
 889                         drc_index = hp_elog->_drc_u.ic.index;
 890                         rc = dlpar_memory_add_by_ic(count, drc_index);
 891                         break;
 892                 default:
 893                         rc = -EINVAL;
 894                         break;
 895                 }
 896
 897                 break;
 898         case PSERIES_HP_ELOG_ACTION_REMOVE:
 899                 switch (hp_elog->id_type) {
 900                 case PSERIES_HP_ELOG_ID_DRC_COUNT:
 901                         count = hp_elog->_drc_u.drc_count;
 902                         rc = dlpar_memory_remove_by_count(count);
 903                         break;
 904                 case PSERIES_HP_ELOG_ID_DRC_INDEX:
 905                         drc_index = hp_elog->_drc_u.drc_index;
 906                         rc = dlpar_memory_remove_by_index(drc_index);
 907                         break;
 908                 case PSERIES_HP_ELOG_ID_DRC_IC:
 909                         count = hp_elog->_drc_u.ic.count;
 910                         drc_index = hp_elog->_drc_u.ic.index;
 911                         rc = dlpar_memory_remove_by_ic(count, drc_index);
 912                         break;
 913                 default:
 914                         rc = -EINVAL;
 915                         break;
 916                 }
 917
 918                 break;
 919         default:
 920                 pr_err("Invalid action (%d) specified\n", hp_elog->action);
 921                 rc = -EINVAL;
 922                 break;
 923         }
 924
 925         if (!rc)
 926                 rc = drmem_update_dt();
 927
 928         unlock_device_hotplug();
 929         return rc;
 930 }
 931
 932 static int pseries_add_mem_node(struct device_node *np)
 933 {
 934         const __be32 *prop;
 935         unsigned long base;
 936         unsigned long lmb_size;
 937         int ret = -EINVAL;
 938         int addr_cells, size_cells;
 939
 940         /*
 941          * Check to see if we are actually adding memory
 942          */
 943         if (!of_node_is_type(np, "memory"))
 944                 return 0;
 945
 946         /*
 947          * Find the base and size of the memblock
 948          */
 949         prop = of_get_property(np, "reg", NULL);
 950         if (!prop)
 951                 return ret;
 952
 953         addr_cells = of_n_addr_cells(np);
 954         size_cells = of_n_size_cells(np);
 955         /*
 956          * "reg" property represents (addr,size) tuple.
 957          */
 958         base = of_read_number(prop, addr_cells);
 959         prop += addr_cells;
 960         lmb_size = of_read_number(prop, size_cells);
 961
 962         /*
 963          * Update memory region to represent the memory add
 964          */
 965         ret = memblock_add(base, lmb_size);
 966         return (ret < 0) ? -EINVAL : 0;
 967 }
 968
 969 static int pseries_memory_notifier(struct notifier_block *nb,
 970                                    unsigned long action, void *data)
 971 {
 972         struct of_reconfig_data *rd = data;
 973         int err = 0;
 974
 975         switch (action) {
 976         case OF_RECONFIG_ATTACH_NODE:
 977                 err = pseries_add_mem_node(rd->dn);
 978                 break;
 979         case OF_RECONFIG_DETACH_NODE:
 980                 err = pseries_remove_mem_node(rd->dn);
 981                 break;
 982         case OF_RECONFIG_UPDATE_PROPERTY:
 983                 if (!strcmp(rd->dn->name,
 984                             "ibm,dynamic-reconfiguration-memory"))
 985                         drmem_update_lmbs(rd->prop);
 986         }
 987         return notifier_from_errno(err);
 988 }
 989
 990 static struct notifier_block pseries_mem_nb = {
 991         .notifier_call = pseries_memory_notifier,
 992 };
 993
 994 static int __init pseries_memory_hotplug_init(void)
 995 {
 996         if (firmware_has_feature(FW_FEATURE_LPAR))
 997                 of_reconfig_notifier_register(&pseries_mem_nb);
 998
 999         return 0;
1000 }
1001 machine_device_initcall(pseries, pseries_memory_hotplug_init);