arch/x86/mm/discontig_32.c

   1 /*
   2  * Written by: Patricia Gaughen <gone@us.ibm.com>, IBM Corporation
   3  * August 2002: added remote node KVA remap - Martin J. Bligh
   4  *
   5  * Copyright (C) 2002, IBM Corp.
   6  *
   7  * All rights reserved.
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful, but
  15  * WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  17  * NON INFRINGEMENT.  See the GNU General Public License for more
  18  * details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  */
  24
  25 #include <linux/mm.h>
  26 #include <linux/bootmem.h>
  27 #include <linux/mmzone.h>
  28 #include <linux/highmem.h>
  29 #include <linux/initrd.h>
  30 #include <linux/nodemask.h>
  31 #include <linux/module.h>
  32 #include <linux/kexec.h>
  33 #include <linux/pfn.h>
  34 #include <linux/swap.h>
  35 #include <linux/acpi.h>
  36
  37 #include <asm/e820.h>
  38 #include <asm/setup.h>
  39 #include <asm/mmzone.h>
  40 #include <asm/bios_ebda.h>
  41 #include <asm/proto.h>
  42
  43 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  44 EXPORT_SYMBOL(node_data);
  45
  46 /*
  47  * numa interface - we expect the numa architecture specific code to have
  48  *                  populated the following initialisation.
  49  *
  50  * 1) node_online_map  - the map of all nodes configured (online) in the system
  51  * 2) node_start_pfn   - the starting page frame number for a node
  52  * 3) node_end_pfn     - the ending page fram number for a node
  53  */
  54 unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly;
  55 unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly;
  56
  57
  58 #ifdef CONFIG_DISCONTIGMEM
  59 /*
  60  * 4) physnode_map     - the mapping between a pfn and owning node
  61  * physnode_map keeps track of the physical memory layout of a generic
  62  * numa node on a 64Mb break (each element of the array will
  63  * represent 64Mb of memory and will be marked by the node id.  so,
  64  * if the first gig is on node 0, and the second gig is on node 1
  65  * physnode_map will contain:
  66  *
  67  *     physnode_map[0-15] = 0;
  68  *     physnode_map[16-31] = 1;
  69  *     physnode_map[32- ] = -1;
  70  */
  71 s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1};
  72 EXPORT_SYMBOL(physnode_map);
  73
  74 void memory_present(int nid, unsigned long start, unsigned long end)
  75 {
  76         unsigned long pfn;
  77
  78         printk(KERN_INFO "Node: %d, start_pfn: %lx, end_pfn: %lx\n",
  79                         nid, start, end);
  80         printk(KERN_DEBUG "  Setting physnode_map array to node %d for pfns:\n", nid);
  81         printk(KERN_DEBUG "  ");
  82         for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) {
  83                 physnode_map[pfn / PAGES_PER_ELEMENT] = nid;
  84                 printk(KERN_CONT "%lx ", pfn);
  85         }
  86         printk(KERN_CONT "\n");
  87 }
  88
  89 unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
  90                                               unsigned long end_pfn)
  91 {
  92         unsigned long nr_pages = end_pfn - start_pfn;
  93
  94         if (!nr_pages)
  95                 return 0;
  96
  97         return (nr_pages + 1) * sizeof(struct page);
  98 }
  99 #endif
 100
 101 extern unsigned long find_max_low_pfn(void);
 102 extern unsigned long highend_pfn, highstart_pfn;
 103
 104 #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)
 105
 106 unsigned long node_remap_size[MAX_NUMNODES];
 107 static void *node_remap_start_vaddr[MAX_NUMNODES];
 108 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
 109
 110 static unsigned long kva_start_pfn;
 111 static unsigned long kva_pages;
 112 /*
 113  * FLAT - support for basic PC memory model with discontig enabled, essentially
 114  *        a single node with all available processors in it with a flat
 115  *        memory map.
 116  */
 117 int __init get_memcfg_numa_flat(void)
 118 {
 119         printk(KERN_DEBUG "NUMA - single node, flat memory mode\n");
 120
 121         node_start_pfn[0] = 0;
 122         node_end_pfn[0] = max_pfn;
 123         e820_register_active_regions(0, 0, max_pfn);
 124         memory_present(0, 0, max_pfn);
 125         node_remap_size[0] = node_memmap_size_bytes(0, 0, max_pfn);
 126
 127         /* Indicate there is one node available. */
 128         nodes_clear(node_online_map);
 129         node_set_online(0);
 130         return 1;
 131 }
 132
 133 /*
 134  * Find the highest page frame number we have available for the node
 135  */
 136 static void __init propagate_e820_map_node(int nid)
 137 {
 138         if (node_end_pfn[nid] > max_pfn)
 139                 node_end_pfn[nid] = max_pfn;
 140         /*
 141          * if a user has given mem=XXXX, then we need to make sure
 142          * that the node _starts_ before that, too, not just ends
 143          */
 144         if (node_start_pfn[nid] > max_pfn)
 145                 node_start_pfn[nid] = max_pfn;
 146         BUG_ON(node_start_pfn[nid] > node_end_pfn[nid]);
 147 }
 148
 149 /*
 150  * Allocate memory for the pg_data_t for this node via a crude pre-bootmem
 151  * method.  For node zero take this from the bottom of memory, for
 152  * subsequent nodes place them at node_remap_start_vaddr which contains
 153  * node local data in physically node local memory.  See setup_memory()
 154  * for details.
 155  */
 156 static void __init allocate_pgdat(int nid)
 157 {
 158         char buf[16];
 159
 160         if (node_has_online_mem(nid) && node_remap_start_vaddr[nid])
 161                 NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
 162         else {
 163                 unsigned long pgdat_phys;
 164                 pgdat_phys = find_e820_area(min_low_pfn<<PAGE_SHIFT,
 165                                  max_pfn_mapped<<PAGE_SHIFT,
 166                                  sizeof(pg_data_t),
 167                                  PAGE_SIZE);
 168                 NODE_DATA(nid) = (pg_data_t *)(pfn_to_kaddr(pgdat_phys>>PAGE_SHIFT));
 169                 memset(buf, 0, sizeof(buf));
 170                 sprintf(buf, "NODE_DATA %d",  nid);
 171                 reserve_early(pgdat_phys, pgdat_phys + sizeof(pg_data_t), buf);
 172         }
 173         printk(KERN_DEBUG "allocate_pgdat: node %d NODE_DATA %08lx\n",
 174                 nid, (unsigned long)NODE_DATA(nid));
 175 }
 176
 177 /*
 178  * In the DISCONTIGMEM and SPARSEMEM memory model, a portion of the kernel
 179  * virtual address space (KVA) is reserved and portions of nodes are mapped
 180  * using it. This is to allow node-local memory to be allocated for
 181  * structures that would normally require ZONE_NORMAL. The memory is
 182  * allocated with alloc_remap() and callers should be prepared to allocate
 183  * from the bootmem allocator instead.
 184  */
 185 static unsigned long node_remap_start_pfn[MAX_NUMNODES];
 186 static void *node_remap_end_vaddr[MAX_NUMNODES];
 187 static void *node_remap_alloc_vaddr[MAX_NUMNODES];
 188 static unsigned long node_remap_offset[MAX_NUMNODES];
 189
 190 void *alloc_remap(int nid, unsigned long size)
 191 {
 192         void *allocation = node_remap_alloc_vaddr[nid];
 193
 194         size = ALIGN(size, L1_CACHE_BYTES);
 195
 196         if (!allocation || (allocation + size) >= node_remap_end_vaddr[nid])
 197                 return 0;
 198
 199         node_remap_alloc_vaddr[nid] += size;
 200         memset(allocation, 0, size);
 201
 202         return allocation;
 203 }
 204
 205 static void __init remap_numa_kva(void)
 206 {
 207         void *vaddr;
 208         unsigned long pfn;
 209         int node;
 210
 211         for_each_online_node(node) {
 212                 printk(KERN_DEBUG "remap_numa_kva: node %d\n", node);
 213                 for (pfn=0; pfn < node_remap_size[node]; pfn += PTRS_PER_PTE) {
 214                         vaddr = node_remap_start_vaddr[node]+(pfn<<PAGE_SHIFT);
 215                         printk(KERN_DEBUG "remap_numa_kva: %08lx to pfn %08lx\n",
 216                                 (unsigned long)vaddr,
 217                                 node_remap_start_pfn[node] + pfn);
 218                         set_pmd_pfn((ulong) vaddr,
 219                                 node_remap_start_pfn[node] + pfn,
 220                                 PAGE_KERNEL_LARGE);
 221                 }
 222         }
 223 }
 224
 225 static unsigned long calculate_numa_remap_pages(void)
 226 {
 227         int nid;
 228         unsigned long size, reserve_pages = 0;
 229
 230         for_each_online_node(nid) {
 231                 u64 node_kva_target;
 232                 u64 node_kva_final;
 233
 234                 /*
 235                  * The acpi/srat node info can show hot-add memroy zones
 236                  * where memory could be added but not currently present.
 237                  */
 238                 printk(KERN_DEBUG "node %d pfn: [%lx - %lx]\n",
 239                         nid, node_start_pfn[nid], node_end_pfn[nid]);
 240                 if (node_start_pfn[nid] > max_pfn)
 241                         continue;
 242                 if (!node_end_pfn[nid])
 243                         continue;
 244                 if (node_end_pfn[nid] > max_pfn)
 245                         node_end_pfn[nid] = max_pfn;
 246
 247                 /* ensure the remap includes space for the pgdat. */
 248                 size = node_remap_size[nid] + sizeof(pg_data_t);
 249
 250                 /* convert size to large (pmd size) pages, rounding up */
 251                 size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES;
 252                 /* now the roundup is correct, convert to PAGE_SIZE pages */
 253                 size = size * PTRS_PER_PTE;
 254
 255                 node_kva_target = round_down(node_end_pfn[nid] - size,
 256                                                  PTRS_PER_PTE);
 257                 node_kva_target <<= PAGE_SHIFT;
 258                 do {
 259                         node_kva_final = find_e820_area(node_kva_target,
 260                                         ((u64)node_end_pfn[nid])<<PAGE_SHIFT,
 261                                                 ((u64)size)<<PAGE_SHIFT,
 262                                                 LARGE_PAGE_BYTES);
 263                         node_kva_target -= LARGE_PAGE_BYTES;
 264                 } while (node_kva_final == -1ULL &&
 265                          (node_kva_target>>PAGE_SHIFT) > (node_start_pfn[nid]));
 266
 267                 if (node_kva_final == -1ULL)
 268                         panic("Can not get kva ram\n");
 269
 270                 node_remap_size[nid] = size;
 271                 node_remap_offset[nid] = reserve_pages;
 272                 reserve_pages += size;
 273                 printk(KERN_DEBUG "Reserving %ld pages of KVA for lmem_map of"
 274                                   " node %d at %llx\n",
 275                                 size, nid, node_kva_final>>PAGE_SHIFT);
 276
 277                 /*
 278                  *  prevent kva address below max_low_pfn want it on system
 279                  *  with less memory later.
 280                  *  layout will be: KVA address , KVA RAM
 281                  *
 282                  *  we are supposed to only record the one less then max_low_pfn
 283                  *  but we could have some hole in high memory, and it will only
 284                  *  check page_is_ram(pfn) && !page_is_reserved_early(pfn) to decide
 285                  *  to use it as free.
 286                  *  So reserve_early here, hope we don't run out of that array
 287                  */
 288                 reserve_early(node_kva_final,
 289                               node_kva_final+(((u64)size)<<PAGE_SHIFT),
 290                               "KVA RAM");
 291
 292                 node_remap_start_pfn[nid] = node_kva_final>>PAGE_SHIFT;
 293                 remove_active_range(nid, node_remap_start_pfn[nid],
 294                                          node_remap_start_pfn[nid] + size);
 295         }
 296         printk(KERN_INFO "Reserving total of %lx pages for numa KVA remap\n",
 297                         reserve_pages);
 298         return reserve_pages;
 299 }
 300
 301 static void init_remap_allocator(int nid)
 302 {
 303         node_remap_start_vaddr[nid] = pfn_to_kaddr(
 304                         kva_start_pfn + node_remap_offset[nid]);
 305         node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] +
 306                 (node_remap_size[nid] * PAGE_SIZE);
 307         node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] +
 308                 ALIGN(sizeof(pg_data_t), PAGE_SIZE);
 309
 310         printk(KERN_DEBUG "node %d will remap to vaddr %08lx - %08lx\n", nid,
 311                 (ulong) node_remap_start_vaddr[nid],
 312                 (ulong) node_remap_end_vaddr[nid]);
 313 }
 314
 315 void __init initmem_init(unsigned long start_pfn,
 316                                   unsigned long end_pfn)
 317 {
 318         int nid;
 319         long kva_target_pfn;
 320
 321         /*
 322          * When mapping a NUMA machine we allocate the node_mem_map arrays
 323          * from node local memory.  They are then mapped directly into KVA
 324          * between zone normal and vmalloc space.  Calculate the size of
 325          * this space and use it to adjust the boundary between ZONE_NORMAL
 326          * and ZONE_HIGHMEM.
 327          */
 328
 329         get_memcfg_numa();
 330
 331         kva_pages = roundup(calculate_numa_remap_pages(), PTRS_PER_PTE);
 332
 333         kva_target_pfn = round_down(max_low_pfn - kva_pages, PTRS_PER_PTE);
 334         do {
 335                 kva_start_pfn = find_e820_area(kva_target_pfn<<PAGE_SHIFT,
 336                                         max_low_pfn<<PAGE_SHIFT,
 337                                         kva_pages<<PAGE_SHIFT,
 338                                         PTRS_PER_PTE<<PAGE_SHIFT) >> PAGE_SHIFT;
 339                 kva_target_pfn -= PTRS_PER_PTE;
 340         } while (kva_start_pfn == -1UL && kva_target_pfn > min_low_pfn);
 341
 342         if (kva_start_pfn == -1UL)
 343                 panic("Can not get kva space\n");
 344
 345         printk(KERN_INFO "kva_start_pfn ~ %lx max_low_pfn ~ %lx\n",
 346                 kva_start_pfn, max_low_pfn);
 347         printk(KERN_INFO "max_pfn = %lx\n", max_pfn);
 348
 349         /* avoid clash with initrd */
 350         reserve_early(kva_start_pfn<<PAGE_SHIFT,
 351                       (kva_start_pfn + kva_pages)<<PAGE_SHIFT,
 352                      "KVA PG");
 353 #ifdef CONFIG_HIGHMEM
 354         highstart_pfn = highend_pfn = max_pfn;
 355         if (max_pfn > max_low_pfn)
 356                 highstart_pfn = max_low_pfn;
 357         printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 358                pages_to_mb(highend_pfn - highstart_pfn));
 359         num_physpages = highend_pfn;
 360         high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
 361 #else
 362         num_physpages = max_low_pfn;
 363         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
 364 #endif
 365         printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
 366                         pages_to_mb(max_low_pfn));
 367         printk(KERN_DEBUG "max_low_pfn = %lx, highstart_pfn = %lx\n",
 368                         max_low_pfn, highstart_pfn);
 369
 370         printk(KERN_DEBUG "Low memory ends at vaddr %08lx\n",
 371                         (ulong) pfn_to_kaddr(max_low_pfn));
 372         for_each_online_node(nid) {
 373                 init_remap_allocator(nid);
 374
 375                 allocate_pgdat(nid);
 376         }
 377         remap_numa_kva();
 378
 379         printk(KERN_DEBUG "High memory starts at vaddr %08lx\n",
 380                         (ulong) pfn_to_kaddr(highstart_pfn));
 381         for_each_online_node(nid)
 382                 propagate_e820_map_node(nid);
 383
 384         for_each_online_node(nid)
 385                 memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
 386
 387         NODE_DATA(0)->bdata = &bootmem_node_data[0];
 388         setup_bootmem_allocator();
 389 }
 390
 391 void __init set_highmem_pages_init(void)
 392 {
 393 #ifdef CONFIG_HIGHMEM
 394         struct zone *zone;
 395         int nid;
 396
 397         for_each_zone(zone) {
 398                 unsigned long zone_start_pfn, zone_end_pfn;
 399
 400                 if (!is_highmem(zone))
 401                         continue;
 402
 403                 zone_start_pfn = zone->zone_start_pfn;
 404                 zone_end_pfn = zone_start_pfn + zone->spanned_pages;
 405
 406                 nid = zone_to_nid(zone);
 407                 printk(KERN_INFO "Initializing %s for node %d (%08lx:%08lx)\n",
 408                                 zone->name, nid, zone_start_pfn, zone_end_pfn);
 409
 410                 add_highpages_with_active_regions(nid, zone_start_pfn,
 411                                  zone_end_pfn);
 412         }
 413         totalram_pages += totalhigh_pages;
 414 #endif
 415 }
 416
 417 #ifdef CONFIG_MEMORY_HOTPLUG
 418 static int paddr_to_nid(u64 addr)
 419 {
 420         int nid;
 421         unsigned long pfn = PFN_DOWN(addr);
 422
 423         for_each_node(nid)
 424                 if (node_start_pfn[nid] <= pfn &&
 425                     pfn < node_end_pfn[nid])
 426                         return nid;
 427
 428         return -1;
 429 }
 430
 431 /*
 432  * This function is used to ask node id BEFORE memmap and mem_section's
 433  * initialization (pfn_to_nid() can't be used yet).
 434  * If _PXM is not defined on ACPI's DSDT, node id must be found by this.
 435  */
 436 int memory_add_physaddr_to_nid(u64 addr)
 437 {
 438         int nid = paddr_to_nid(addr);
 439         return (nid >= 0) ? nid : 0;
 440 }
 441
 442 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 443 #endif
 444