arch/powerpc/mm/numa.c

   1 /*
   2  * pSeries NUMA support
   3  *
   4  * Copyright (C) 2002 Anton Blanchard <[email protected]>, IBM
   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 #include <linux/threads.h>
  12 #include <linux/bootmem.h>
  13 #include <linux/init.h>
  14 #include <linux/mm.h>
  15 #include <linux/mmzone.h>
  16 #include <linux/export.h>
  17 #include <linux/nodemask.h>
  18 #include <linux/cpu.h>
  19 #include <linux/notifier.h>
  20 #include <linux/memblock.h>
  21 #include <linux/of.h>
  22 #include <linux/pfn.h>
  23 #include <linux/cpuset.h>
  24 #include <linux/node.h>
  25 #include <linux/stop_machine.h>
  26 #include <linux/proc_fs.h>
  27 #include <linux/seq_file.h>
  28 #include <linux/uaccess.h>
  29 #include <linux/slab.h>
  30 #include <asm/cputhreads.h>
  31 #include <asm/sparsemem.h>
  32 #include <asm/prom.h>
  33 #include <asm/smp.h>
  34 #include <asm/firmware.h>
  35 #include <asm/paca.h>
  36 #include <asm/hvcall.h>
  37 #include <asm/setup.h>
  38 #include <asm/vdso.h>
  39
  40 static int numa_enabled = 1;
  41
  42 static char *cmdline __initdata;
  43
  44 static int numa_debug;
  45 #define dbg(args...) if (numa_debug) { printk(KERN_INFO args); }
  46
  47 int numa_cpu_lookup_table[NR_CPUS];
  48 cpumask_var_t node_to_cpumask_map[MAX_NUMNODES];
  49 struct pglist_data *node_data[MAX_NUMNODES];
  50
  51 EXPORT_SYMBOL(numa_cpu_lookup_table);
  52 EXPORT_SYMBOL(node_to_cpumask_map);
  53 EXPORT_SYMBOL(node_data);
  54
  55 static int min_common_depth;
  56 static int n_mem_addr_cells, n_mem_size_cells;
  57 static int form1_affinity;
  58
  59 #define MAX_DISTANCE_REF_POINTS 4
  60 static int distance_ref_points_depth;
  61 static const __be32 *distance_ref_points;
  62 static int distance_lookup_table[MAX_NUMNODES][MAX_DISTANCE_REF_POINTS];
  63
  64 /*
  65  * Allocate node_to_cpumask_map based on number of available nodes
  66  * Requires node_possible_map to be valid.
  67  *
  68  * Note: cpumask_of_node() is not valid until after this is done.
  69  */
  70 static void __init setup_node_to_cpumask_map(void)
  71 {
  72         unsigned int node;
  73
  74         /* setup nr_node_ids if not done yet */
  75         if (nr_node_ids == MAX_NUMNODES)
  76                 setup_nr_node_ids();
  77
  78         /* allocate the map */
  79         for (node = 0; node < nr_node_ids; node++)
  80                 alloc_bootmem_cpumask_var(&node_to_cpumask_map[node]);
  81
  82         /* cpumask_of_node() will now work */
  83         dbg("Node to cpumask map for %d nodes\n", nr_node_ids);
  84 }
  85
  86 static int __init fake_numa_create_new_node(unsigned long end_pfn,
  87                                                 unsigned int *nid)
  88 {
  89         unsigned long long mem;
  90         char *p = cmdline;
  91         static unsigned int fake_nid;
  92         static unsigned long long curr_boundary;
  93
  94         /*
  95          * Modify node id, iff we started creating NUMA nodes
  96          * We want to continue from where we left of the last time
  97          */
  98         if (fake_nid)
  99                 *nid = fake_nid;
 100         /*
 101          * In case there are no more arguments to parse, the
 102          * node_id should be the same as the last fake node id
 103          * (we've handled this above).
 104          */
 105         if (!p)
 106                 return 0;
 107
 108         mem = memparse(p, &p);
 109         if (!mem)
 110                 return 0;
 111
 112         if (mem < curr_boundary)
 113                 return 0;
 114
 115         curr_boundary = mem;
 116
 117         if ((end_pfn << PAGE_SHIFT) > mem) {
 118                 /*
 119                  * Skip commas and spaces
 120                  */
 121                 while (*p == ',' || *p == ' ' || *p == '\t')
 122                         p++;
 123
 124                 cmdline = p;
 125                 fake_nid++;
 126                 *nid = fake_nid;
 127                 dbg("created new fake_node with id %d\n", fake_nid);
 128                 return 1;
 129         }
 130         return 0;
 131 }
 132
 133 /*
 134  * get_node_active_region - Return active region containing pfn
 135  * Active range returned is empty if none found.
 136  * @pfn: The page to return the region for
 137  * @node_ar: Returned set to the active region containing @pfn
 138  */
 139 static void __init get_node_active_region(unsigned long pfn,
 140                                           struct node_active_region *node_ar)
 141 {
 142         unsigned long start_pfn, end_pfn;
 143         int i, nid;
 144
 145         for_each_mem_pfn_range(i, MAX_NUMNODES, &start_pfn, &end_pfn, &nid) {
 146                 if (pfn >= start_pfn && pfn < end_pfn) {
 147                         node_ar->nid = nid;
 148                         node_ar->start_pfn = start_pfn;
 149                         node_ar->end_pfn = end_pfn;
 150                         break;
 151                 }
 152         }
 153 }
 154
 155 static void map_cpu_to_node(int cpu, int node)
 156 {
 157         numa_cpu_lookup_table[cpu] = node;
 158
 159         dbg("adding cpu %d to node %d\n", cpu, node);
 160
 161         if (!(cpumask_test_cpu(cpu, node_to_cpumask_map[node])))
 162                 cpumask_set_cpu(cpu, node_to_cpumask_map[node]);
 163 }
 164
 165 #if defined(CONFIG_HOTPLUG_CPU) || defined(CONFIG_PPC_SPLPAR)
 166 static void unmap_cpu_from_node(unsigned long cpu)
 167 {
 168         int node = numa_cpu_lookup_table[cpu];
 169
 170         dbg("removing cpu %lu from node %d\n", cpu, node);
 171
 172         if (cpumask_test_cpu(cpu, node_to_cpumask_map[node])) {
 173                 cpumask_clear_cpu(cpu, node_to_cpumask_map[node]);
 174         } else {
 175                 printk(KERN_ERR "WARNING: cpu %lu not found in node %d\n",
 176                        cpu, node);
 177         }
 178 }
 179 #endif /* CONFIG_HOTPLUG_CPU || CONFIG_PPC_SPLPAR */
 180
 181 /* must hold reference to node during call */
 182 static const __be32 *of_get_associativity(struct device_node *dev)
 183 {
 184         return of_get_property(dev, "ibm,associativity", NULL);
 185 }
 186
 187 /*
 188  * Returns the property linux,drconf-usable-memory if
 189  * it exists (the property exists only in kexec/kdump kernels,
 190  * added by kexec-tools)
 191  */
 192 static const __be32 *of_get_usable_memory(struct device_node *memory)
 193 {
 194         const __be32 *prop;
 195         u32 len;
 196         prop = of_get_property(memory, "linux,drconf-usable-memory", &len);
 197         if (!prop || len < sizeof(unsigned int))
 198                 return 0;
 199         return prop;
 200 }
 201
 202 int __node_distance(int a, int b)
 203 {
 204         int i;
 205         int distance = LOCAL_DISTANCE;
 206
 207         if (!form1_affinity)
 208                 return ((a == b) ? LOCAL_DISTANCE : REMOTE_DISTANCE);
 209
 210         for (i = 0; i < distance_ref_points_depth; i++) {
 211                 if (distance_lookup_table[a][i] == distance_lookup_table[b][i])
 212                         break;
 213
 214                 /* Double the distance for each NUMA level */
 215                 distance *= 2;
 216         }
 217
 218         return distance;
 219 }
 220
 221 static void initialize_distance_lookup_table(int nid,
 222                 const __be32 *associativity)
 223 {
 224         int i;
 225
 226         if (!form1_affinity)
 227                 return;
 228
 229         for (i = 0; i < distance_ref_points_depth; i++) {
 230                 const __be32 *entry;
 231
 232                 entry = &associativity[be32_to_cpu(distance_ref_points[i])];
 233                 distance_lookup_table[nid][i] = of_read_number(entry, 1);
 234         }
 235 }
 236
 237 /* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
 238  * info is found.
 239  */
 240 static int associativity_to_nid(const __be32 *associativity)
 241 {
 242         int nid = -1;
 243
 244         if (min_common_depth == -1)
 245                 goto out;
 246
 247         if (of_read_number(associativity, 1) >= min_common_depth)
 248                 nid = of_read_number(&associativity[min_common_depth], 1);
 249
 250         /* POWER4 LPAR uses 0xffff as invalid node */
 251         if (nid == 0xffff || nid >= MAX_NUMNODES)
 252                 nid = -1;
 253
 254         if (nid > 0 &&
 255             of_read_number(associativity, 1) >= distance_ref_points_depth)
 256                 initialize_distance_lookup_table(nid, associativity);
 257
 258 out:
 259         return nid;
 260 }
 261
 262 /* Returns the nid associated with the given device tree node,
 263  * or -1 if not found.
 264  */
 265 static int of_node_to_nid_single(struct device_node *device)
 266 {
 267         int nid = -1;
 268         const __be32 *tmp;
 269
 270         tmp = of_get_associativity(device);
 271         if (tmp)
 272                 nid = associativity_to_nid(tmp);
 273         return nid;
 274 }
 275
 276 /* Walk the device tree upwards, looking for an associativity id */
 277 int of_node_to_nid(struct device_node *device)
 278 {
 279         struct device_node *tmp;
 280         int nid = -1;
 281
 282         of_node_get(device);
 283         while (device) {
 284                 nid = of_node_to_nid_single(device);
 285                 if (nid != -1)
 286                         break;
 287
 288                 tmp = device;
 289                 device = of_get_parent(tmp);
 290                 of_node_put(tmp);
 291         }
 292         of_node_put(device);
 293
 294         return nid;
 295 }
 296 EXPORT_SYMBOL_GPL(of_node_to_nid);
 297
 298 static int __init find_min_common_depth(void)
 299 {
 300         int depth;
 301         struct device_node *root;
 302
 303         if (firmware_has_feature(FW_FEATURE_OPAL))
 304                 root = of_find_node_by_path("/ibm,opal");
 305         else
 306                 root = of_find_node_by_path("/rtas");
 307         if (!root)
 308                 root = of_find_node_by_path("/");
 309
 310         /*
 311          * This property is a set of 32-bit integers, each representing
 312          * an index into the ibm,associativity nodes.
 313          *
 314          * With form 0 affinity the first integer is for an SMP configuration
 315          * (should be all 0's) and the second is for a normal NUMA
 316          * configuration. We have only one level of NUMA.
 317          *
 318          * With form 1 affinity the first integer is the most significant
 319          * NUMA boundary and the following are progressively less significant
 320          * boundaries. There can be more than one level of NUMA.
 321          */
 322         distance_ref_points = of_get_property(root,
 323                                         "ibm,associativity-reference-points",
 324                                         &distance_ref_points_depth);
 325
 326         if (!distance_ref_points) {
 327                 dbg("NUMA: ibm,associativity-reference-points not found.\n");
 328                 goto err;
 329         }
 330
 331         distance_ref_points_depth /= sizeof(int);
 332
 333         if (firmware_has_feature(FW_FEATURE_OPAL) ||
 334             firmware_has_feature(FW_FEATURE_TYPE1_AFFINITY)) {
 335                 dbg("Using form 1 affinity\n");
 336                 form1_affinity = 1;
 337         }
 338
 339         if (form1_affinity) {
 340                 depth = of_read_number(distance_ref_points, 1);
 341         } else {
 342                 if (distance_ref_points_depth < 2) {
 343                         printk(KERN_WARNING "NUMA: "
 344                                 "short ibm,associativity-reference-points\n");
 345                         goto err;
 346                 }
 347
 348                 depth = of_read_number(&distance_ref_points[1], 1);
 349         }
 350
 351         /*
 352          * Warn and cap if the hardware supports more than
 353          * MAX_DISTANCE_REF_POINTS domains.
 354          */
 355         if (distance_ref_points_depth > MAX_DISTANCE_REF_POINTS) {
 356                 printk(KERN_WARNING "NUMA: distance array capped at "
 357                         "%d entries\n", MAX_DISTANCE_REF_POINTS);
 358                 distance_ref_points_depth = MAX_DISTANCE_REF_POINTS;
 359         }
 360
 361         of_node_put(root);
 362         return depth;
 363
 364 err:
 365         of_node_put(root);
 366         return -1;
 367 }
 368
 369 static void __init get_n_mem_cells(int *n_addr_cells, int *n_size_cells)
 370 {
 371         struct device_node *memory = NULL;
 372
 373         memory = of_find_node_by_type(memory, "memory");
 374         if (!memory)
 375                 panic("numa.c: No memory nodes found!");
 376
 377         *n_addr_cells = of_n_addr_cells(memory);
 378         *n_size_cells = of_n_size_cells(memory);
 379         of_node_put(memory);
 380 }
 381
 382 static unsigned long read_n_cells(int n, const __be32 **buf)
 383 {
 384         unsigned long result = 0;
 385
 386         while (n--) {
 387                 result = (result << 32) | of_read_number(*buf, 1);
 388                 (*buf)++;
 389         }
 390         return result;
 391 }
 392
 393 /*
 394  * Read the next memblock list entry from the ibm,dynamic-memory property
 395  * and return the information in the provided of_drconf_cell structure.
 396  */
 397 static void read_drconf_cell(struct of_drconf_cell *drmem, const __be32 **cellp)
 398 {
 399         const __be32 *cp;
 400
 401         drmem->base_addr = read_n_cells(n_mem_addr_cells, cellp);
 402
 403         cp = *cellp;
 404         drmem->drc_index = of_read_number(cp, 1);
 405         drmem->reserved = of_read_number(&cp[1], 1);
 406         drmem->aa_index = of_read_number(&cp[2], 1);
 407         drmem->flags = of_read_number(&cp[3], 1);
 408
 409         *cellp = cp + 4;
 410 }
 411
 412 /*
 413  * Retrieve and validate the ibm,dynamic-memory property of the device tree.
 414  *
 415  * The layout of the ibm,dynamic-memory property is a number N of memblock
 416  * list entries followed by N memblock list entries.  Each memblock list entry
 417  * contains information as laid out in the of_drconf_cell struct above.
 418  */
 419 static int of_get_drconf_memory(struct device_node *memory, const __be32 **dm)
 420 {
 421         const __be32 *prop;
 422         u32 len, entries;
 423
 424         prop = of_get_property(memory, "ibm,dynamic-memory", &len);
 425         if (!prop || len < sizeof(unsigned int))
 426                 return 0;
 427
 428         entries = of_read_number(prop++, 1);
 429
 430         /* Now that we know the number of entries, revalidate the size
 431          * of the property read in to ensure we have everything
 432          */
 433         if (len < (entries * (n_mem_addr_cells + 4) + 1) * sizeof(unsigned int))
 434                 return 0;
 435
 436         *dm = prop;
 437         return entries;
 438 }
 439
 440 /*
 441  * Retrieve and validate the ibm,lmb-size property for drconf memory
 442  * from the device tree.
 443  */
 444 static u64 of_get_lmb_size(struct device_node *memory)
 445 {
 446         const __be32 *prop;
 447         u32 len;
 448
 449         prop = of_get_property(memory, "ibm,lmb-size", &len);
 450         if (!prop || len < sizeof(unsigned int))
 451                 return 0;
 452
 453         return read_n_cells(n_mem_size_cells, &prop);
 454 }
 455
 456 struct assoc_arrays {
 457         u32     n_arrays;
 458         u32     array_sz;
 459         const __be32 *arrays;
 460 };
 461
 462 /*
 463  * Retrieve and validate the list of associativity arrays for drconf
 464  * memory from the ibm,associativity-lookup-arrays property of the
 465  * device tree..
 466  *
 467  * The layout of the ibm,associativity-lookup-arrays property is a number N
 468  * indicating the number of associativity arrays, followed by a number M
 469  * indicating the size of each associativity array, followed by a list
 470  * of N associativity arrays.
 471  */
 472 static int of_get_assoc_arrays(struct device_node *memory,
 473                                struct assoc_arrays *aa)
 474 {
 475         const __be32 *prop;
 476         u32 len;
 477
 478         prop = of_get_property(memory, "ibm,associativity-lookup-arrays", &len);
 479         if (!prop || len < 2 * sizeof(unsigned int))
 480                 return -1;
 481
 482         aa->n_arrays = of_read_number(prop++, 1);
 483         aa->array_sz = of_read_number(prop++, 1);
 484
 485         /* Now that we know the number of arrays and size of each array,
 486          * revalidate the size of the property read in.
 487          */
 488         if (len < (aa->n_arrays * aa->array_sz + 2) * sizeof(unsigned int))
 489                 return -1;
 490
 491         aa->arrays = prop;
 492         return 0;
 493 }
 494
 495 /*
 496  * This is like of_node_to_nid_single() for memory represented in the
 497  * ibm,dynamic-reconfiguration-memory node.
 498  */
 499 static int of_drconf_to_nid_single(struct of_drconf_cell *drmem,
 500                                    struct assoc_arrays *aa)
 501 {
 502         int default_nid = 0;
 503         int nid = default_nid;
 504         int index;
 505
 506         if (min_common_depth > 0 && min_common_depth <= aa->array_sz &&
 507             !(drmem->flags & DRCONF_MEM_AI_INVALID) &&
 508             drmem->aa_index < aa->n_arrays) {
 509                 index = drmem->aa_index * aa->array_sz + min_common_depth - 1;
 510                 nid = of_read_number(&aa->arrays[index], 1);
 511
 512                 if (nid == 0xffff || nid >= MAX_NUMNODES)
 513                         nid = default_nid;
 514         }
 515
 516         return nid;
 517 }
 518
 519 /*
 520  * Figure out to which domain a cpu belongs and stick it there.
 521  * Return the id of the domain used.
 522  */
 523 static int numa_setup_cpu(unsigned long lcpu)
 524 {
 525         int nid = 0;
 526         struct device_node *cpu = of_get_cpu_node(lcpu, NULL);
 527
 528         if (!cpu) {
 529                 WARN_ON(1);
 530                 goto out;
 531         }
 532
 533         nid = of_node_to_nid_single(cpu);
 534
 535         if (nid < 0 || !node_online(nid))
 536                 nid = first_online_node;
 537 out:
 538         map_cpu_to_node(lcpu, nid);
 539
 540         of_node_put(cpu);
 541
 542         return nid;
 543 }
 544
 545 static int cpu_numa_callback(struct notifier_block *nfb, unsigned long action,
 546                              void *hcpu)
 547 {
 548         unsigned long lcpu = (unsigned long)hcpu;
 549         int ret = NOTIFY_DONE;
 550
 551         switch (action) {
 552         case CPU_UP_PREPARE:
 553         case CPU_UP_PREPARE_FROZEN:
 554                 numa_setup_cpu(lcpu);
 555                 ret = NOTIFY_OK;
 556                 break;
 557 #ifdef CONFIG_HOTPLUG_CPU
 558         case CPU_DEAD:
 559         case CPU_DEAD_FROZEN:
 560         case CPU_UP_CANCELED:
 561         case CPU_UP_CANCELED_FROZEN:
 562                 unmap_cpu_from_node(lcpu);
 563                 break;
 564                 ret = NOTIFY_OK;
 565 #endif
 566         }
 567         return ret;
 568 }
 569
 570 /*
 571  * Check and possibly modify a memory region to enforce the memory limit.
 572  *
 573  * Returns the size the region should have to enforce the memory limit.
 574  * This will either be the original value of size, a truncated value,
 575  * or zero. If the returned value of size is 0 the region should be
 576  * discarded as it lies wholly above the memory limit.
 577  */
 578 static unsigned long __init numa_enforce_memory_limit(unsigned long start,
 579                                                       unsigned long size)
 580 {
 581         /*
 582          * We use memblock_end_of_DRAM() in here instead of memory_limit because
 583          * we've already adjusted it for the limit and it takes care of
 584          * having memory holes below the limit.  Also, in the case of
 585          * iommu_is_off, memory_limit is not set but is implicitly enforced.
 586          */
 587
 588         if (start + size <= memblock_end_of_DRAM())
 589                 return size;
 590
 591         if (start >= memblock_end_of_DRAM())
 592                 return 0;
 593
 594         return memblock_end_of_DRAM() - start;
 595 }
 596
 597 /*
 598  * Reads the counter for a given entry in
 599  * linux,drconf-usable-memory property
 600  */
 601 static inline int __init read_usm_ranges(const __be32 **usm)
 602 {
 603         /*
 604          * For each lmb in ibm,dynamic-memory a corresponding
 605          * entry in linux,drconf-usable-memory property contains
 606          * a counter followed by that many (base, size) duple.
 607          * read the counter from linux,drconf-usable-memory
 608          */
 609         return read_n_cells(n_mem_size_cells, usm);
 610 }
 611
 612 /*
 613  * Extract NUMA information from the ibm,dynamic-reconfiguration-memory
 614  * node.  This assumes n_mem_{addr,size}_cells have been set.
 615  */
 616 static void __init parse_drconf_memory(struct device_node *memory)
 617 {
 618         const __be32 *uninitialized_var(dm), *usm;
 619         unsigned int n, rc, ranges, is_kexec_kdump = 0;
 620         unsigned long lmb_size, base, size, sz;
 621         int nid;
 622         struct assoc_arrays aa = { .arrays = NULL };
 623
 624         n = of_get_drconf_memory(memory, &dm);
 625         if (!n)
 626                 return;
 627
 628         lmb_size = of_get_lmb_size(memory);
 629         if (!lmb_size)
 630                 return;
 631
 632         rc = of_get_assoc_arrays(memory, &aa);
 633         if (rc)
 634                 return;
 635
 636         /* check if this is a kexec/kdump kernel */
 637         usm = of_get_usable_memory(memory);
 638         if (usm != NULL)
 639                 is_kexec_kdump = 1;
 640
 641         for (; n != 0; --n) {
 642                 struct of_drconf_cell drmem;
 643
 644                 read_drconf_cell(&drmem, &dm);
 645
 646                 /* skip this block if the reserved bit is set in flags (0x80)
 647                    or if the block is not assigned to this partition (0x8) */
 648                 if ((drmem.flags & DRCONF_MEM_RESERVED)
 649                     || !(drmem.flags & DRCONF_MEM_ASSIGNED))
 650                         continue;
 651
 652                 base = drmem.base_addr;
 653                 size = lmb_size;
 654                 ranges = 1;
 655
 656                 if (is_kexec_kdump) {
 657                         ranges = read_usm_ranges(&usm);
 658                         if (!ranges) /* there are no (base, size) duple */
 659                                 continue;
 660                 }
 661                 do {
 662                         if (is_kexec_kdump) {
 663                                 base = read_n_cells(n_mem_addr_cells, &usm);
 664                                 size = read_n_cells(n_mem_size_cells, &usm);
 665                         }
 666                         nid = of_drconf_to_nid_single(&drmem, &aa);
 667                         fake_numa_create_new_node(
 668                                 ((base + size) >> PAGE_SHIFT),
 669                                            &nid);
 670                         node_set_online(nid);
 671                         sz = numa_enforce_memory_limit(base, size);
 672                         if (sz)
 673                                 memblock_set_node(base, sz, nid);
 674                 } while (--ranges);
 675         }
 676 }
 677
 678 static int __init parse_numa_properties(void)
 679 {
 680         struct device_node *memory;
 681         int default_nid = 0;
 682         unsigned long i;
 683
 684         if (numa_enabled == 0) {
 685                 printk(KERN_WARNING "NUMA disabled by user\n");
 686                 return -1;
 687         }
 688
 689         min_common_depth = find_min_common_depth();
 690
 691         if (min_common_depth < 0)
 692                 return min_common_depth;
 693
 694         dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
 695
 696         /*
 697          * Even though we connect cpus to numa domains later in SMP
 698          * init, we need to know the node ids now. This is because
 699          * each node to be onlined must have NODE_DATA etc backing it.
 700          */
 701         for_each_present_cpu(i) {
 702                 struct device_node *cpu;
 703                 int nid;
 704
 705                 cpu = of_get_cpu_node(i, NULL);
 706                 BUG_ON(!cpu);
 707                 nid = of_node_to_nid_single(cpu);
 708                 of_node_put(cpu);
 709
 710                 /*
 711                  * Don't fall back to default_nid yet -- we will plug
 712                  * cpus into nodes once the memory scan has discovered
 713                  * the topology.
 714                  */
 715                 if (nid < 0)
 716                         continue;
 717                 node_set_online(nid);
 718         }
 719
 720         get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
 721
 722         for_each_node_by_type(memory, "memory") {
 723                 unsigned long start;
 724                 unsigned long size;
 725                 int nid;
 726                 int ranges;
 727                 const __be32 *memcell_buf;
 728                 unsigned int len;
 729
 730                 memcell_buf = of_get_property(memory,
 731                         "linux,usable-memory", &len);
 732                 if (!memcell_buf || len <= 0)
 733                         memcell_buf = of_get_property(memory, "reg", &len);
 734                 if (!memcell_buf || len <= 0)
 735                         continue;
 736
 737                 /* ranges in cell */
 738                 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
 739 new_range:
 740                 /* these are order-sensitive, and modify the buffer pointer */
 741                 start = read_n_cells(n_mem_addr_cells, &memcell_buf);
 742                 size = read_n_cells(n_mem_size_cells, &memcell_buf);
 743
 744                 /*
 745                  * Assumption: either all memory nodes or none will
 746                  * have associativity properties.  If none, then
 747                  * everything goes to default_nid.
 748                  */
 749                 nid = of_node_to_nid_single(memory);
 750                 if (nid < 0)
 751                         nid = default_nid;
 752
 753                 fake_numa_create_new_node(((start + size) >> PAGE_SHIFT), &nid);
 754                 node_set_online(nid);
 755
 756                 if (!(size = numa_enforce_memory_limit(start, size))) {
 757                         if (--ranges)
 758                                 goto new_range;
 759                         else
 760                                 continue;
 761                 }
 762
 763                 memblock_set_node(start, size, nid);
 764
 765                 if (--ranges)
 766                         goto new_range;
 767         }
 768
 769         /*
 770          * Now do the same thing for each MEMBLOCK listed in the
 771          * ibm,dynamic-memory property in the
 772          * ibm,dynamic-reconfiguration-memory node.
 773          */
 774         memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
 775         if (memory)
 776                 parse_drconf_memory(memory);
 777
 778         return 0;
 779 }
 780
 781 static void __init setup_nonnuma(void)
 782 {
 783         unsigned long top_of_ram = memblock_end_of_DRAM();
 784         unsigned long total_ram = memblock_phys_mem_size();
 785         unsigned long start_pfn, end_pfn;
 786         unsigned int nid = 0;
 787         struct memblock_region *reg;
 788
 789         printk(KERN_DEBUG "Top of RAM: 0x%lx, Total RAM: 0x%lx\n",
 790                top_of_ram, total_ram);
 791         printk(KERN_DEBUG "Memory hole size: %ldMB\n",
 792                (top_of_ram - total_ram) >> 20);
 793
 794         for_each_memblock(memory, reg) {
 795                 start_pfn = memblock_region_memory_base_pfn(reg);
 796                 end_pfn = memblock_region_memory_end_pfn(reg);
 797
 798                 fake_numa_create_new_node(end_pfn, &nid);
 799                 memblock_set_node(PFN_PHYS(start_pfn),
 800                                   PFN_PHYS(end_pfn - start_pfn), nid);
 801                 node_set_online(nid);
 802         }
 803 }
 804
 805 void __init dump_numa_cpu_topology(void)
 806 {
 807         unsigned int node;
 808         unsigned int cpu, count;
 809
 810         if (min_common_depth == -1 || !numa_enabled)
 811                 return;
 812
 813         for_each_online_node(node) {
 814                 printk(KERN_DEBUG "Node %d CPUs:", node);
 815
 816                 count = 0;
 817                 /*
 818                  * If we used a CPU iterator here we would miss printing
 819                  * the holes in the cpumap.
 820                  */
 821                 for (cpu = 0; cpu < nr_cpu_ids; cpu++) {
 822                         if (cpumask_test_cpu(cpu,
 823                                         node_to_cpumask_map[node])) {
 824                                 if (count == 0)
 825                                         printk(" %u", cpu);
 826                                 ++count;
 827                         } else {
 828                                 if (count > 1)
 829                                         printk("-%u", cpu - 1);
 830                                 count = 0;
 831                         }
 832                 }
 833
 834                 if (count > 1)
 835                         printk("-%u", nr_cpu_ids - 1);
 836                 printk("\n");
 837         }
 838 }
 839
 840 static void __init dump_numa_memory_topology(void)
 841 {
 842         unsigned int node;
 843         unsigned int count;
 844
 845         if (min_common_depth == -1 || !numa_enabled)
 846                 return;
 847
 848         for_each_online_node(node) {
 849                 unsigned long i;
 850
 851                 printk(KERN_DEBUG "Node %d Memory:", node);
 852
 853                 count = 0;
 854
 855                 for (i = 0; i < memblock_end_of_DRAM();
 856                      i += (1 << SECTION_SIZE_BITS)) {
 857                         if (early_pfn_to_nid(i >> PAGE_SHIFT) == node) {
 858                                 if (count == 0)
 859                                         printk(" 0x%lx", i);
 860                                 ++count;
 861                         } else {
 862                                 if (count > 0)
 863                                         printk("-0x%lx", i);
 864                                 count = 0;
 865                         }
 866                 }
 867
 868                 if (count > 0)
 869                         printk("-0x%lx", i);
 870                 printk("\n");
 871         }
 872 }
 873
 874 /*
 875  * Allocate some memory, satisfying the memblock or bootmem allocator where
 876  * required. nid is the preferred node and end is the physical address of
 877  * the highest address in the node.
 878  *
 879  * Returns the virtual address of the memory.
 880  */
 881 static void __init *careful_zallocation(int nid, unsigned long size,
 882                                        unsigned long align,
 883                                        unsigned long end_pfn)
 884 {
 885         void *ret;
 886         int new_nid;
 887         unsigned long ret_paddr;
 888
 889         ret_paddr = __memblock_alloc_base(size, align, end_pfn << PAGE_SHIFT);
 890
 891         /* retry over all memory */
 892         if (!ret_paddr)
 893                 ret_paddr = __memblock_alloc_base(size, align, memblock_end_of_DRAM());
 894
 895         if (!ret_paddr)
 896                 panic("numa.c: cannot allocate %lu bytes for node %d",
 897                       size, nid);
 898
 899         ret = __va(ret_paddr);
 900
 901         /*
 902          * We initialize the nodes in numeric order: 0, 1, 2...
 903          * and hand over control from the MEMBLOCK allocator to the
 904          * bootmem allocator.  If this function is called for
 905          * node 5, then we know that all nodes <5 are using the
 906          * bootmem allocator instead of the MEMBLOCK allocator.
 907          *
 908          * So, check the nid from which this allocation came
 909          * and double check to see if we need to use bootmem
 910          * instead of the MEMBLOCK.  We don't free the MEMBLOCK memory
 911          * since it would be useless.
 912          */
 913         new_nid = early_pfn_to_nid(ret_paddr >> PAGE_SHIFT);
 914         if (new_nid < nid) {
 915                 ret = __alloc_bootmem_node(NODE_DATA(new_nid),
 916                                 size, align, 0);
 917
 918                 dbg("alloc_bootmem %p %lx\n", ret, size);
 919         }
 920
 921         memset(ret, 0, size);
 922         return ret;
 923 }
 924
 925 static struct notifier_block ppc64_numa_nb = {
 926         .notifier_call = cpu_numa_callback,
 927         .priority = 1 /* Must run before sched domains notifier. */
 928 };
 929
 930 static void __init mark_reserved_regions_for_nid(int nid)
 931 {
 932         struct pglist_data *node = NODE_DATA(nid);
 933         struct memblock_region *reg;
 934
 935         for_each_memblock(reserved, reg) {
 936                 unsigned long physbase = reg->base;
 937                 unsigned long size = reg->size;
 938                 unsigned long start_pfn = physbase >> PAGE_SHIFT;
 939                 unsigned long end_pfn = PFN_UP(physbase + size);
 940                 struct node_active_region node_ar;
 941                 unsigned long node_end_pfn = node->node_start_pfn +
 942                                              node->node_spanned_pages;
 943
 944                 /*
 945                  * Check to make sure that this memblock.reserved area is
 946                  * within the bounds of the node that we care about.
 947                  * Checking the nid of the start and end points is not
 948                  * sufficient because the reserved area could span the
 949                  * entire node.
 950                  */
 951                 if (end_pfn <= node->node_start_pfn ||
 952                     start_pfn >= node_end_pfn)
 953                         continue;
 954
 955                 get_node_active_region(start_pfn, &node_ar);
 956                 while (start_pfn < end_pfn &&
 957                         node_ar.start_pfn < node_ar.end_pfn) {
 958                         unsigned long reserve_size = size;
 959                         /*
 960                          * if reserved region extends past active region
 961                          * then trim size to active region
 962                          */
 963                         if (end_pfn > node_ar.end_pfn)
 964                                 reserve_size = (node_ar.end_pfn << PAGE_SHIFT)
 965                                         - physbase;
 966                         /*
 967                          * Only worry about *this* node, others may not
 968                          * yet have valid NODE_DATA().
 969                          */
 970                         if (node_ar.nid == nid) {
 971                                 dbg("reserve_bootmem %lx %lx nid=%d\n",
 972                                         physbase, reserve_size, node_ar.nid);
 973                                 reserve_bootmem_node(NODE_DATA(node_ar.nid),
 974                                                 physbase, reserve_size,
 975                                                 BOOTMEM_DEFAULT);
 976                         }
 977                         /*
 978                          * if reserved region is contained in the active region
 979                          * then done.
 980                          */
 981                         if (end_pfn <= node_ar.end_pfn)
 982                                 break;
 983
 984                         /*
 985                          * reserved region extends past the active region
 986                          *   get next active region that contains this
 987                          *   reserved region
 988                          */
 989                         start_pfn = node_ar.end_pfn;
 990                         physbase = start_pfn << PAGE_SHIFT;
 991                         size = size - reserve_size;
 992                         get_node_active_region(start_pfn, &node_ar);
 993                 }
 994         }
 995 }
 996
 997
 998 void __init do_init_bootmem(void)
 999 {
1000         int nid;
1001
1002         min_low_pfn = 0;
1003         max_low_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
1004         max_pfn = max_low_pfn;
1005
1006         if (parse_numa_properties())
1007                 setup_nonnuma();
1008         else
1009                 dump_numa_memory_topology();
1010
1011         for_each_online_node(nid) {
1012                 unsigned long start_pfn, end_pfn;
1013                 void *bootmem_vaddr;
1014                 unsigned long bootmap_pages;
1015
1016                 get_pfn_range_for_nid(nid, &start_pfn, &end_pfn);
1017
1018                 /*
1019                  * Allocate the node structure node local if possible
1020                  *
1021                  * Be careful moving this around, as it relies on all
1022                  * previous nodes' bootmem to be initialized and have
1023                  * all reserved areas marked.
1024                  */
1025                 NODE_DATA(nid) = careful_zallocation(nid,
1026                                         sizeof(struct pglist_data),
1027                                         SMP_CACHE_BYTES, end_pfn);
1028
1029                 dbg("node %d\n", nid);
1030                 dbg("NODE_DATA() = %p\n", NODE_DATA(nid));
1031
1032                 NODE_DATA(nid)->bdata = &bootmem_node_data[nid];
1033                 NODE_DATA(nid)->node_start_pfn = start_pfn;
1034                 NODE_DATA(nid)->node_spanned_pages = end_pfn - start_pfn;
1035
1036                 if (NODE_DATA(nid)->node_spanned_pages == 0)
1037                         continue;
1038
1039                 dbg("start_paddr = %lx\n", start_pfn << PAGE_SHIFT);
1040                 dbg("end_paddr = %lx\n", end_pfn << PAGE_SHIFT);
1041
1042                 bootmap_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
1043                 bootmem_vaddr = careful_zallocation(nid,
1044                                         bootmap_pages << PAGE_SHIFT,
1045                                         PAGE_SIZE, end_pfn);
1046
1047                 dbg("bootmap_vaddr = %p\n", bootmem_vaddr);
1048
1049                 init_bootmem_node(NODE_DATA(nid),
1050                                   __pa(bootmem_vaddr) >> PAGE_SHIFT,
1051                                   start_pfn, end_pfn);
1052
1053                 free_bootmem_with_active_regions(nid, end_pfn);
1054                 /*
1055                  * Be very careful about moving this around.  Future
1056                  * calls to careful_zallocation() depend on this getting
1057                  * done correctly.
1058                  */
1059                 mark_reserved_regions_for_nid(nid);
1060                 sparse_memory_present_with_active_regions(nid);
1061         }
1062
1063         init_bootmem_done = 1;
1064
1065         /*
1066          * Now bootmem is initialised we can create the node to cpumask
1067          * lookup tables and setup the cpu callback to populate them.
1068          */
1069         setup_node_to_cpumask_map();
1070
1071         register_cpu_notifier(&ppc64_numa_nb);
1072         cpu_numa_callback(&ppc64_numa_nb, CPU_UP_PREPARE,
1073                           (void *)(unsigned long)boot_cpuid);
1074 }
1075
1076 void __init paging_init(void)
1077 {
1078         unsigned long max_zone_pfns[MAX_NR_ZONES];
1079         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
1080         max_zone_pfns[ZONE_DMA] = memblock_end_of_DRAM() >> PAGE_SHIFT;
1081         free_area_init_nodes(max_zone_pfns);
1082 }
1083
1084 static int __init early_numa(char *p)
1085 {
1086         if (!p)
1087                 return 0;
1088
1089         if (strstr(p, "off"))
1090                 numa_enabled = 0;
1091
1092         if (strstr(p, "debug"))
1093                 numa_debug = 1;
1094
1095         p = strstr(p, "fake=");
1096         if (p)
1097                 cmdline = p + strlen("fake=");
1098
1099         return 0;
1100 }
1101 early_param("numa", early_numa);
1102
1103 #ifdef CONFIG_MEMORY_HOTPLUG
1104 /*
1105  * Find the node associated with a hot added memory section for
1106  * memory represented in the device tree by the property
1107  * ibm,dynamic-reconfiguration-memory/ibm,dynamic-memory.
1108  */
1109 static int hot_add_drconf_scn_to_nid(struct device_node *memory,
1110                                      unsigned long scn_addr)
1111 {
1112         const __be32 *dm;
1113         unsigned int drconf_cell_cnt, rc;
1114         unsigned long lmb_size;
1115         struct assoc_arrays aa;
1116         int nid = -1;
1117
1118         drconf_cell_cnt = of_get_drconf_memory(memory, &dm);
1119         if (!drconf_cell_cnt)
1120                 return -1;
1121
1122         lmb_size = of_get_lmb_size(memory);
1123         if (!lmb_size)
1124                 return -1;
1125
1126         rc = of_get_assoc_arrays(memory, &aa);
1127         if (rc)
1128                 return -1;
1129
1130         for (; drconf_cell_cnt != 0; --drconf_cell_cnt) {
1131                 struct of_drconf_cell drmem;
1132
1133                 read_drconf_cell(&drmem, &dm);
1134
1135                 /* skip this block if it is reserved or not assigned to
1136                  * this partition */
1137                 if ((drmem.flags & DRCONF_MEM_RESERVED)
1138                     || !(drmem.flags & DRCONF_MEM_ASSIGNED))
1139                         continue;
1140
1141                 if ((scn_addr < drmem.base_addr)
1142                     || (scn_addr >= (drmem.base_addr + lmb_size)))
1143                         continue;
1144
1145                 nid = of_drconf_to_nid_single(&drmem, &aa);
1146                 break;
1147         }
1148
1149         return nid;
1150 }
1151
1152 /*
1153  * Find the node associated with a hot added memory section for memory
1154  * represented in the device tree as a node (i.e. memory@XXXX) for
1155  * each memblock.
1156  */
1157 int hot_add_node_scn_to_nid(unsigned long scn_addr)
1158 {
1159         struct device_node *memory;
1160         int nid = -1;
1161
1162         for_each_node_by_type(memory, "memory") {
1163                 unsigned long start, size;
1164                 int ranges;
1165                 const __be32 *memcell_buf;
1166                 unsigned int len;
1167
1168                 memcell_buf = of_get_property(memory, "reg", &len);
1169                 if (!memcell_buf || len <= 0)
1170                         continue;
1171
1172                 /* ranges in cell */
1173                 ranges = (len >> 2) / (n_mem_addr_cells + n_mem_size_cells);
1174
1175                 while (ranges--) {
1176                         start = read_n_cells(n_mem_addr_cells, &memcell_buf);
1177                         size = read_n_cells(n_mem_size_cells, &memcell_buf);
1178
1179                         if ((scn_addr < start) || (scn_addr >= (start + size)))
1180                                 continue;
1181
1182                         nid = of_node_to_nid_single(memory);
1183                         break;
1184                 }
1185
1186                 if (nid >= 0)
1187                         break;
1188         }
1189
1190         of_node_put(memory);
1191
1192         return nid;
1193 }
1194
1195 /*
1196  * Find the node associated with a hot added memory section.  Section
1197  * corresponds to a SPARSEMEM section, not an MEMBLOCK.  It is assumed that
1198  * sections are fully contained within a single MEMBLOCK.
1199  */
1200 int hot_add_scn_to_nid(unsigned long scn_addr)
1201 {
1202         struct device_node *memory = NULL;
1203         int nid, found = 0;
1204
1205         if (!numa_enabled || (min_common_depth < 0))
1206                 return first_online_node;
1207
1208         memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1209         if (memory) {
1210                 nid = hot_add_drconf_scn_to_nid(memory, scn_addr);
1211                 of_node_put(memory);
1212         } else {
1213                 nid = hot_add_node_scn_to_nid(scn_addr);
1214         }
1215
1216         if (nid < 0 || !node_online(nid))
1217                 nid = first_online_node;
1218
1219         if (NODE_DATA(nid)->node_spanned_pages)
1220                 return nid;
1221
1222         for_each_online_node(nid) {
1223                 if (NODE_DATA(nid)->node_spanned_pages) {
1224                         found = 1;
1225                         break;
1226                 }
1227         }
1228
1229         BUG_ON(!found);
1230         return nid;
1231 }
1232
1233 static u64 hot_add_drconf_memory_max(void)
1234 {
1235         struct device_node *memory = NULL;
1236         unsigned int drconf_cell_cnt = 0;
1237         u64 lmb_size = 0;
1238         const __be32 *dm = 0;
1239
1240         memory = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
1241         if (memory) {
1242                 drconf_cell_cnt = of_get_drconf_memory(memory, &dm);
1243                 lmb_size = of_get_lmb_size(memory);
1244                 of_node_put(memory);
1245         }
1246         return lmb_size * drconf_cell_cnt;
1247 }
1248
1249 /*
1250  * memory_hotplug_max - return max address of memory that may be added
1251  *
1252  * This is currently only used on systems that support drconfig memory
1253  * hotplug.
1254  */
1255 u64 memory_hotplug_max(void)
1256 {
1257         return max(hot_add_drconf_memory_max(), memblock_end_of_DRAM());
1258 }
1259 #endif /* CONFIG_MEMORY_HOTPLUG */
1260
1261 /* Virtual Processor Home Node (VPHN) support */
1262 #ifdef CONFIG_PPC_SPLPAR
1263 struct topology_update_data {
1264         struct topology_update_data *next;
1265         unsigned int cpu;
1266         int old_nid;
1267         int new_nid;
1268 };
1269
1270 static u8 vphn_cpu_change_counts[NR_CPUS][MAX_DISTANCE_REF_POINTS];
1271 static cpumask_t cpu_associativity_changes_mask;
1272 static int vphn_enabled;
1273 static int prrn_enabled;
1274 static void reset_topology_timer(void);
1275
1276 /*
1277  * Store the current values of the associativity change counters in the
1278  * hypervisor.
1279  */
1280 static void setup_cpu_associativity_change_counters(void)
1281 {
1282         int cpu;
1283
1284         /* The VPHN feature supports a maximum of 8 reference points */
1285         BUILD_BUG_ON(MAX_DISTANCE_REF_POINTS > 8);
1286
1287         for_each_possible_cpu(cpu) {
1288                 int i;
1289                 u8 *counts = vphn_cpu_change_counts[cpu];
1290                 volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
1291
1292                 for (i = 0; i < distance_ref_points_depth; i++)
1293                         counts[i] = hypervisor_counts[i];
1294         }
1295 }
1296
1297 /*
1298  * The hypervisor maintains a set of 8 associativity change counters in
1299  * the VPA of each cpu that correspond to the associativity levels in the
1300  * ibm,associativity-reference-points property. When an associativity
1301  * level changes, the corresponding counter is incremented.
1302  *
1303  * Set a bit in cpu_associativity_changes_mask for each cpu whose home
1304  * node associativity levels have changed.
1305  *
1306  * Returns the number of cpus with unhandled associativity changes.
1307  */
1308 static int update_cpu_associativity_changes_mask(void)
1309 {
1310         int cpu;
1311         cpumask_t *changes = &cpu_associativity_changes_mask;
1312
1313         for_each_possible_cpu(cpu) {
1314                 int i, changed = 0;
1315                 u8 *counts = vphn_cpu_change_counts[cpu];
1316                 volatile u8 *hypervisor_counts = lppaca[cpu].vphn_assoc_counts;
1317
1318                 for (i = 0; i < distance_ref_points_depth; i++) {
1319                         if (hypervisor_counts[i] != counts[i]) {
1320                                 counts[i] = hypervisor_counts[i];
1321                                 changed = 1;
1322                         }
1323                 }
1324                 if (changed) {
1325                         cpumask_or(changes, changes, cpu_sibling_mask(cpu));
1326                         cpu = cpu_last_thread_sibling(cpu);
1327                 }
1328         }
1329
1330         return cpumask_weight(changes);
1331 }
1332
1333 /*
1334  * 6 64-bit registers unpacked into 12 32-bit associativity values. To form
1335  * the complete property we have to add the length in the first cell.
1336  */
1337 #define VPHN_ASSOC_BUFSIZE (6*sizeof(u64)/sizeof(u32) + 1)
1338
1339 /*
1340  * Convert the associativity domain numbers returned from the hypervisor
1341  * to the sequence they would appear in the ibm,associativity property.
1342  */
1343 static int vphn_unpack_associativity(const long *packed, __be32 *unpacked)
1344 {
1345         int i, nr_assoc_doms = 0;
1346         const __be16 *field = (const __be16 *) packed;
1347
1348 #define VPHN_FIELD_UNUSED       (0xffff)
1349 #define VPHN_FIELD_MSB          (0x8000)
1350 #define VPHN_FIELD_MASK         (~VPHN_FIELD_MSB)
1351
1352         for (i = 1; i < VPHN_ASSOC_BUFSIZE; i++) {
1353                 if (be16_to_cpup(field) == VPHN_FIELD_UNUSED) {
1354                         /* All significant fields processed, and remaining
1355                          * fields contain the reserved value of all 1's.
1356                          * Just store them.
1357                          */
1358                         unpacked[i] = *((__be32 *)field);
1359                         field += 2;
1360                 } else if (be16_to_cpup(field) & VPHN_FIELD_MSB) {
1361                         /* Data is in the lower 15 bits of this field */
1362                         unpacked[i] = cpu_to_be32(
1363                                 be16_to_cpup(field) & VPHN_FIELD_MASK);
1364                         field++;
1365                         nr_assoc_doms++;
1366                 } else {
1367                         /* Data is in the lower 15 bits of this field
1368                          * concatenated with the next 16 bit field
1369                          */
1370                         unpacked[i] = *((__be32 *)field);
1371                         field += 2;
1372                         nr_assoc_doms++;
1373                 }
1374         }
1375
1376         /* The first cell contains the length of the property */
1377         unpacked[0] = cpu_to_be32(nr_assoc_doms);
1378
1379         return nr_assoc_doms;
1380 }
1381
1382 /*
1383  * Retrieve the new associativity information for a virtual processor's
1384  * home node.
1385  */
1386 static long hcall_vphn(unsigned long cpu, __be32 *associativity)
1387 {
1388         long rc;
1389         long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
1390         u64 flags = 1;
1391         int hwcpu = get_hard_smp_processor_id(cpu);
1392
1393         rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu);
1394         vphn_unpack_associativity(retbuf, associativity);
1395
1396         return rc;
1397 }
1398
1399 static long vphn_get_associativity(unsigned long cpu,
1400                                         __be32 *associativity)
1401 {
1402         long rc;
1403
1404         rc = hcall_vphn(cpu, associativity);
1405
1406         switch (rc) {
1407         case H_FUNCTION:
1408                 printk(KERN_INFO
1409                         "VPHN is not supported. Disabling polling...\n");
1410                 stop_topology_update();
1411                 break;
1412         case H_HARDWARE:
1413                 printk(KERN_ERR
1414                         "hcall_vphn() experienced a hardware fault "
1415                         "preventing VPHN. Disabling polling...\n");
1416                 stop_topology_update();
1417         }
1418
1419         return rc;
1420 }
1421
1422 /*
1423  * Update the CPU maps and sysfs entries for a single CPU when its NUMA
1424  * characteristics change. This function doesn't perform any locking and is
1425  * only safe to call from stop_machine().
1426  */
1427 static int update_cpu_topology(void *data)
1428 {
1429         struct topology_update_data *update;
1430         unsigned long cpu;
1431
1432         if (!data)
1433                 return -EINVAL;
1434
1435         cpu = smp_processor_id();
1436
1437         for (update = data; update; update = update->next) {
1438                 if (cpu != update->cpu)
1439                         continue;
1440
1441                 unmap_cpu_from_node(update->cpu);
1442                 map_cpu_to_node(update->cpu, update->new_nid);
1443                 vdso_getcpu_init();
1444         }
1445
1446         return 0;
1447 }
1448
1449 /*
1450  * Update the node maps and sysfs entries for each cpu whose home node
1451  * has changed. Returns 1 when the topology has changed, and 0 otherwise.
1452  */
1453 int arch_update_cpu_topology(void)
1454 {
1455         unsigned int cpu, sibling, changed = 0;
1456         struct topology_update_data *updates, *ud;
1457         __be32 associativity[VPHN_ASSOC_BUFSIZE] = {0};
1458         cpumask_t updated_cpus;
1459         struct device *dev;
1460         int weight, new_nid, i = 0;
1461
1462         weight = cpumask_weight(&cpu_associativity_changes_mask);
1463         if (!weight)
1464                 return 0;
1465
1466         updates = kzalloc(weight * (sizeof(*updates)), GFP_KERNEL);
1467         if (!updates)
1468                 return 0;
1469
1470         cpumask_clear(&updated_cpus);
1471
1472         for_each_cpu(cpu, &cpu_associativity_changes_mask) {
1473                 /*
1474                  * If siblings aren't flagged for changes, updates list
1475                  * will be too short. Skip on this update and set for next
1476                  * update.
1477                  */
1478                 if (!cpumask_subset(cpu_sibling_mask(cpu),
1479                                         &cpu_associativity_changes_mask)) {
1480                         pr_info("Sibling bits not set for associativity "
1481                                         "change, cpu%d\n", cpu);
1482                         cpumask_or(&cpu_associativity_changes_mask,
1483                                         &cpu_associativity_changes_mask,
1484                                         cpu_sibling_mask(cpu));
1485                         cpu = cpu_last_thread_sibling(cpu);
1486                         continue;
1487                 }
1488
1489                 /* Use associativity from first thread for all siblings */
1490                 vphn_get_associativity(cpu, associativity);
1491                 new_nid = associativity_to_nid(associativity);
1492                 if (new_nid < 0 || !node_online(new_nid))
1493                         new_nid = first_online_node;
1494
1495                 if (new_nid == numa_cpu_lookup_table[cpu]) {
1496                         cpumask_andnot(&cpu_associativity_changes_mask,
1497                                         &cpu_associativity_changes_mask,
1498                                         cpu_sibling_mask(cpu));
1499                         cpu = cpu_last_thread_sibling(cpu);
1500                         continue;
1501                 }
1502
1503                 for_each_cpu(sibling, cpu_sibling_mask(cpu)) {
1504                         ud = &updates[i++];
1505                         ud->cpu = sibling;
1506                         ud->new_nid = new_nid;
1507                         ud->old_nid = numa_cpu_lookup_table[sibling];
1508                         cpumask_set_cpu(sibling, &updated_cpus);
1509                         if (i < weight)
1510                                 ud->next = &updates[i];
1511                 }
1512                 cpu = cpu_last_thread_sibling(cpu);
1513         }
1514
1515         stop_machine(update_cpu_topology, &updates[0], &updated_cpus);
1516
1517         for (ud = &updates[0]; ud; ud = ud->next) {
1518                 unregister_cpu_under_node(ud->cpu, ud->old_nid);
1519                 register_cpu_under_node(ud->cpu, ud->new_nid);
1520
1521                 dev = get_cpu_device(ud->cpu);
1522                 if (dev)
1523                         kobject_uevent(&dev->kobj, KOBJ_CHANGE);
1524                 cpumask_clear_cpu(ud->cpu, &cpu_associativity_changes_mask);
1525                 changed = 1;
1526         }
1527
1528         kfree(updates);
1529         return changed;
1530 }
1531
1532 static void topology_work_fn(struct work_struct *work)
1533 {
1534         rebuild_sched_domains();
1535 }
1536 static DECLARE_WORK(topology_work, topology_work_fn);
1537
1538 void topology_schedule_update(void)
1539 {
1540         schedule_work(&topology_work);
1541 }
1542
1543 static void topology_timer_fn(unsigned long ignored)
1544 {
1545         if (prrn_enabled && cpumask_weight(&cpu_associativity_changes_mask))
1546                 topology_schedule_update();
1547         else if (vphn_enabled) {
1548                 if (update_cpu_associativity_changes_mask() > 0)
1549                         topology_schedule_update();
1550                 reset_topology_timer();
1551         }
1552 }
1553 static struct timer_list topology_timer =
1554         TIMER_INITIALIZER(topology_timer_fn, 0, 0);
1555
1556 static void reset_topology_timer(void)
1557 {
1558         topology_timer.data = 0;
1559         topology_timer.expires = jiffies + 60 * HZ;
1560         mod_timer(&topology_timer, topology_timer.expires);
1561 }
1562
1563 #ifdef CONFIG_SMP
1564
1565 static void stage_topology_update(int core_id)
1566 {
1567         cpumask_or(&cpu_associativity_changes_mask,
1568                 &cpu_associativity_changes_mask, cpu_sibling_mask(core_id));
1569         reset_topology_timer();
1570 }
1571
1572 static int dt_update_callback(struct notifier_block *nb,
1573                                 unsigned long action, void *data)
1574 {
1575         struct of_prop_reconfig *update;
1576         int rc = NOTIFY_DONE;
1577
1578         switch (action) {
1579         case OF_RECONFIG_UPDATE_PROPERTY:
1580                 update = (struct of_prop_reconfig *)data;
1581                 if (!of_prop_cmp(update->dn->type, "cpu") &&
1582                     !of_prop_cmp(update->prop->name, "ibm,associativity")) {
1583                         u32 core_id;
1584                         of_property_read_u32(update->dn, "reg", &core_id);
1585                         stage_topology_update(core_id);
1586                         rc = NOTIFY_OK;
1587                 }
1588                 break;
1589         }
1590
1591         return rc;
1592 }
1593
1594 static struct notifier_block dt_update_nb = {
1595         .notifier_call = dt_update_callback,
1596 };
1597
1598 #endif
1599
1600 /*
1601  * Start polling for associativity changes.
1602  */
1603 int start_topology_update(void)
1604 {
1605         int rc = 0;
1606
1607         if (firmware_has_feature(FW_FEATURE_PRRN)) {
1608                 if (!prrn_enabled) {
1609                         prrn_enabled = 1;
1610                         vphn_enabled = 0;
1611 #ifdef CONFIG_SMP
1612                         rc = of_reconfig_notifier_register(&dt_update_nb);
1613 #endif
1614                 }
1615         } else if (firmware_has_feature(FW_FEATURE_VPHN) &&
1616                    lppaca_shared_proc(get_lppaca())) {
1617                 if (!vphn_enabled) {
1618                         prrn_enabled = 0;
1619                         vphn_enabled = 1;
1620                         setup_cpu_associativity_change_counters();
1621                         init_timer_deferrable(&topology_timer);
1622                         reset_topology_timer();
1623                 }
1624         }
1625
1626         return rc;
1627 }
1628
1629 /*
1630  * Disable polling for VPHN associativity changes.
1631  */
1632 int stop_topology_update(void)
1633 {
1634         int rc = 0;
1635
1636         if (prrn_enabled) {
1637                 prrn_enabled = 0;
1638 #ifdef CONFIG_SMP
1639                 rc = of_reconfig_notifier_unregister(&dt_update_nb);
1640 #endif
1641         } else if (vphn_enabled) {
1642                 vphn_enabled = 0;
1643                 rc = del_timer_sync(&topology_timer);
1644         }
1645
1646         return rc;
1647 }
1648
1649 int prrn_is_enabled(void)
1650 {
1651         return prrn_enabled;
1652 }
1653
1654 static int topology_read(struct seq_file *file, void *v)
1655 {
1656         if (vphn_enabled || prrn_enabled)
1657                 seq_puts(file, "on\n");
1658         else
1659                 seq_puts(file, "off\n");
1660
1661         return 0;
1662 }
1663
1664 static int topology_open(struct inode *inode, struct file *file)
1665 {
1666         return single_open(file, topology_read, NULL);
1667 }
1668
1669 static ssize_t topology_write(struct file *file, const char __user *buf,
1670                               size_t count, loff_t *off)
1671 {
1672         char kbuf[4]; /* "on" or "off" plus null. */
1673         int read_len;
1674
1675         read_len = count < 3 ? count : 3;
1676         if (copy_from_user(kbuf, buf, read_len))
1677                 return -EINVAL;
1678
1679         kbuf[read_len] = '\0';
1680
1681         if (!strncmp(kbuf, "on", 2))
1682                 start_topology_update();
1683         else if (!strncmp(kbuf, "off", 3))
1684                 stop_topology_update();
1685         else
1686                 return -EINVAL;
1687
1688         return count;
1689 }
1690
1691 static const struct file_operations topology_ops = {
1692         .read = seq_read,
1693         .write = topology_write,
1694         .open = topology_open,
1695         .release = single_release
1696 };
1697
1698 static int topology_update_init(void)
1699 {
1700         start_topology_update();
1701         proc_create("powerpc/topology_updates", 644, NULL, &topology_ops);
1702
1703         return 0;
1704 }
1705 device_initcall(topology_update_init);
1706 #endif /* CONFIG_PPC_SPLPAR */