arch/i386/mm/discontig.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/config.h>
  26 #include <linux/mm.h>
  27 #include <linux/bootmem.h>
  28 #include <linux/mmzone.h>
  29 #include <linux/highmem.h>
  30 #include <linux/initrd.h>
  31 #include <linux/nodemask.h>
  32 #include <linux/module.h>
  33 #include <linux/kexec.h>
  34
  35 #include <asm/e820.h>
  36 #include <asm/setup.h>
  37 #include <asm/mmzone.h>
  38 #include <bios_ebda.h>
  39
  40 struct pglist_data *node_data[MAX_NUMNODES] __read_mostly;
  41 EXPORT_SYMBOL(node_data);
  42 bootmem_data_t node0_bdata;
  43
  44 /*
  45  * numa interface - we expect the numa architecture specfic code to have
  46  *                  populated the following initialisation.
  47  *
  48  * 1) node_online_map  - the map of all nodes configured (online) in the system
  49  * 2) node_start_pfn   - the starting page frame number for a node
  50  * 3) node_end_pfn     - the ending page fram number for a node
  51  */
  52 unsigned long node_start_pfn[MAX_NUMNODES] __read_mostly;
  53 unsigned long node_end_pfn[MAX_NUMNODES] __read_mostly;
  54
  55
  56 #ifdef CONFIG_DISCONTIGMEM
  57 /*
  58  * 4) physnode_map     - the mapping between a pfn and owning node
  59  * physnode_map keeps track of the physical memory layout of a generic
  60  * numa node on a 256Mb break (each element of the array will
  61  * represent 256Mb of memory and will be marked by the node id.  so,
  62  * if the first gig is on node 0, and the second gig is on node 1
  63  * physnode_map will contain:
  64  *
  65  *     physnode_map[0-3] = 0;
  66  *     physnode_map[4-7] = 1;
  67  *     physnode_map[8- ] = -1;
  68  */
  69 s8 physnode_map[MAX_ELEMENTS] __read_mostly = { [0 ... (MAX_ELEMENTS - 1)] = -1};
  70 EXPORT_SYMBOL(physnode_map);
  71
  72 void memory_present(int nid, unsigned long start, unsigned long end)
  73 {
  74         unsigned long pfn;
  75
  76         printk(KERN_INFO "Node: %d, start_pfn: %ld, end_pfn: %ld\n",
  77                         nid, start, end);
  78         printk(KERN_DEBUG "  Setting physnode_map array to node %d for pfns:\n", nid);
  79         printk(KERN_DEBUG "  ");
  80         for (pfn = start; pfn < end; pfn += PAGES_PER_ELEMENT) {
  81                 physnode_map[pfn / PAGES_PER_ELEMENT] = nid;
  82                 printk("%ld ", pfn);
  83         }
  84         printk("\n");
  85 }
  86
  87 unsigned long node_memmap_size_bytes(int nid, unsigned long start_pfn,
  88                                               unsigned long end_pfn)
  89 {
  90         unsigned long nr_pages = end_pfn - start_pfn;
  91
  92         if (!nr_pages)
  93                 return 0;
  94
  95         return (nr_pages + 1) * sizeof(struct page);
  96 }
  97 #endif
  98
  99 extern unsigned long find_max_low_pfn(void);
 100 extern void find_max_pfn(void);
 101 extern void add_one_highpage_init(struct page *, int, int);
 102
 103 extern struct e820map e820;
 104 extern unsigned long init_pg_tables_end;
 105 extern unsigned long highend_pfn, highstart_pfn;
 106 extern unsigned long max_low_pfn;
 107 extern unsigned long totalram_pages;
 108 extern unsigned long totalhigh_pages;
 109
 110 #define LARGE_PAGE_BYTES (PTRS_PER_PTE * PAGE_SIZE)
 111
 112 unsigned long node_remap_start_pfn[MAX_NUMNODES];
 113 unsigned long node_remap_size[MAX_NUMNODES];
 114 unsigned long node_remap_offset[MAX_NUMNODES];
 115 void *node_remap_start_vaddr[MAX_NUMNODES];
 116 void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags);
 117
 118 void *node_remap_end_vaddr[MAX_NUMNODES];
 119 void *node_remap_alloc_vaddr[MAX_NUMNODES];
 120
 121 /*
 122  * FLAT - support for basic PC memory model with discontig enabled, essentially
 123  *        a single node with all available processors in it with a flat
 124  *        memory map.
 125  */
 126 int __init get_memcfg_numa_flat(void)
 127 {
 128         printk("NUMA - single node, flat memory mode\n");
 129
 130         /* Run the memory configuration and find the top of memory. */
 131         find_max_pfn();
 132         node_start_pfn[0] = 0;
 133         node_end_pfn[0] = max_pfn;
 134         memory_present(0, 0, max_pfn);
 135
 136         /* Indicate there is one node available. */
 137         nodes_clear(node_online_map);
 138         node_set_online(0);
 139         return 1;
 140 }
 141
 142 /*
 143  * Find the highest page frame number we have available for the node
 144  */
 145 static void __init find_max_pfn_node(int nid)
 146 {
 147         if (node_end_pfn[nid] > max_pfn)
 148                 node_end_pfn[nid] = max_pfn;
 149         /*
 150          * if a user has given mem=XXXX, then we need to make sure
 151          * that the node _starts_ before that, too, not just ends
 152          */
 153         if (node_start_pfn[nid] > max_pfn)
 154                 node_start_pfn[nid] = max_pfn;
 155         if (node_start_pfn[nid] > node_end_pfn[nid])
 156                 BUG();
 157 }
 158
 159 /* Find the owning node for a pfn. */
 160 int early_pfn_to_nid(unsigned long pfn)
 161 {
 162         int nid;
 163
 164         for_each_node(nid) {
 165                 if (node_end_pfn[nid] == 0)
 166                         break;
 167                 if (node_start_pfn[nid] <= pfn && node_end_pfn[nid] >= pfn)
 168                         return nid;
 169         }
 170
 171         return 0;
 172 }
 173
 174 /*
 175  * Allocate memory for the pg_data_t for this node via a crude pre-bootmem
 176  * method.  For node zero take this from the bottom of memory, for
 177  * subsequent nodes place them at node_remap_start_vaddr which contains
 178  * node local data in physically node local memory.  See setup_memory()
 179  * for details.
 180  */
 181 static void __init allocate_pgdat(int nid)
 182 {
 183         if (nid && node_has_online_mem(nid))
 184                 NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
 185         else {
 186                 NODE_DATA(nid) = (pg_data_t *)(__va(min_low_pfn << PAGE_SHIFT));
 187                 min_low_pfn += PFN_UP(sizeof(pg_data_t));
 188         }
 189 }
 190
 191 void *alloc_remap(int nid, unsigned long size)
 192 {
 193         void *allocation = node_remap_alloc_vaddr[nid];
 194
 195         size = ALIGN(size, L1_CACHE_BYTES);
 196
 197         if (!allocation || (allocation + size) >= node_remap_end_vaddr[nid])
 198                 return 0;
 199
 200         node_remap_alloc_vaddr[nid] += size;
 201         memset(allocation, 0, size);
 202
 203         return allocation;
 204 }
 205
 206 void __init remap_numa_kva(void)
 207 {
 208         void *vaddr;
 209         unsigned long pfn;
 210         int node;
 211
 212         for_each_online_node(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                         set_pmd_pfn((ulong) vaddr,
 216                                 node_remap_start_pfn[node] + pfn,
 217                                 PAGE_KERNEL_LARGE);
 218                 }
 219         }
 220 }
 221
 222 static unsigned long calculate_numa_remap_pages(void)
 223 {
 224         int nid;
 225         unsigned long size, reserve_pages = 0;
 226         unsigned long pfn;
 227
 228         for_each_online_node(nid) {
 229                 /*
 230                  * The acpi/srat node info can show hot-add memroy zones
 231                  * where memory could be added but not currently present.
 232                  */
 233                 if (node_start_pfn[nid] > max_pfn)
 234                         continue;
 235                 if (node_end_pfn[nid] > max_pfn)
 236                         node_end_pfn[nid] = max_pfn;
 237
 238                 /* ensure the remap includes space for the pgdat. */
 239                 size = node_remap_size[nid] + sizeof(pg_data_t);
 240
 241                 /* convert size to large (pmd size) pages, rounding up */
 242                 size = (size + LARGE_PAGE_BYTES - 1) / LARGE_PAGE_BYTES;
 243                 /* now the roundup is correct, convert to PAGE_SIZE pages */
 244                 size = size * PTRS_PER_PTE;
 245
 246                 /*
 247                  * Validate the region we are allocating only contains valid
 248                  * pages.
 249                  */
 250                 for (pfn = node_end_pfn[nid] - size;
 251                      pfn < node_end_pfn[nid]; pfn++)
 252                         if (!page_is_ram(pfn))
 253                                 break;
 254
 255                 if (pfn != node_end_pfn[nid])
 256                         size = 0;
 257
 258                 printk("Reserving %ld pages of KVA for lmem_map of node %d\n",
 259                                 size, nid);
 260                 node_remap_size[nid] = size;
 261                 node_remap_offset[nid] = reserve_pages;
 262                 reserve_pages += size;
 263                 printk("Shrinking node %d from %ld pages to %ld pages\n",
 264                         nid, node_end_pfn[nid], node_end_pfn[nid] - size);
 265
 266                 if (node_end_pfn[nid] & (PTRS_PER_PTE-1)) {
 267                         /*
 268                          * Align node_end_pfn[] and node_remap_start_pfn[] to
 269                          * pmd boundary. remap_numa_kva will barf otherwise.
 270                          */
 271                         printk("Shrinking node %d further by %ld pages for proper alignment\n",
 272                                 nid, node_end_pfn[nid] & (PTRS_PER_PTE-1));
 273                         size +=  node_end_pfn[nid] & (PTRS_PER_PTE-1);
 274                 }
 275
 276                 node_end_pfn[nid] -= size;
 277                 node_remap_start_pfn[nid] = node_end_pfn[nid];
 278         }
 279         printk("Reserving total of %ld pages for numa KVA remap\n",
 280                         reserve_pages);
 281         return reserve_pages;
 282 }
 283
 284 extern void setup_bootmem_allocator(void);
 285 unsigned long __init setup_memory(void)
 286 {
 287         int nid;
 288         unsigned long system_start_pfn, system_max_low_pfn;
 289         unsigned long reserve_pages;
 290
 291         /*
 292          * When mapping a NUMA machine we allocate the node_mem_map arrays
 293          * from node local memory.  They are then mapped directly into KVA
 294          * between zone normal and vmalloc space.  Calculate the size of
 295          * this space and use it to adjust the boundry between ZONE_NORMAL
 296          * and ZONE_HIGHMEM.
 297          */
 298         find_max_pfn();
 299         get_memcfg_numa();
 300
 301         reserve_pages = calculate_numa_remap_pages();
 302
 303         /* partially used pages are not usable - thus round upwards */
 304         system_start_pfn = min_low_pfn = PFN_UP(init_pg_tables_end);
 305
 306         system_max_low_pfn = max_low_pfn = find_max_low_pfn() - reserve_pages;
 307         printk("reserve_pages = %ld find_max_low_pfn() ~ %ld\n",
 308                         reserve_pages, max_low_pfn + reserve_pages);
 309         printk("max_pfn = %ld\n", max_pfn);
 310 #ifdef CONFIG_HIGHMEM
 311         highstart_pfn = highend_pfn = max_pfn;
 312         if (max_pfn > system_max_low_pfn)
 313                 highstart_pfn = system_max_low_pfn;
 314         printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 315                pages_to_mb(highend_pfn - highstart_pfn));
 316 #endif
 317         printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
 318                         pages_to_mb(system_max_low_pfn));
 319         printk("min_low_pfn = %ld, max_low_pfn = %ld, highstart_pfn = %ld\n",
 320                         min_low_pfn, max_low_pfn, highstart_pfn);
 321
 322         printk("Low memory ends at vaddr %08lx\n",
 323                         (ulong) pfn_to_kaddr(max_low_pfn));
 324         for_each_online_node(nid) {
 325                 node_remap_start_vaddr[nid] = pfn_to_kaddr(
 326                                 highstart_pfn + node_remap_offset[nid]);
 327                 /* Init the node remap allocator */
 328                 node_remap_end_vaddr[nid] = node_remap_start_vaddr[nid] +
 329                         (node_remap_size[nid] * PAGE_SIZE);
 330                 node_remap_alloc_vaddr[nid] = node_remap_start_vaddr[nid] +
 331                         ALIGN(sizeof(pg_data_t), PAGE_SIZE);
 332
 333                 allocate_pgdat(nid);
 334                 printk ("node %d will remap to vaddr %08lx - %08lx\n", nid,
 335                         (ulong) node_remap_start_vaddr[nid],
 336                         (ulong) pfn_to_kaddr(highstart_pfn
 337                            + node_remap_offset[nid] + node_remap_size[nid]));
 338         }
 339         printk("High memory starts at vaddr %08lx\n",
 340                         (ulong) pfn_to_kaddr(highstart_pfn));
 341         vmalloc_earlyreserve = reserve_pages * PAGE_SIZE;
 342         for_each_online_node(nid)
 343                 find_max_pfn_node(nid);
 344
 345         memset(NODE_DATA(0), 0, sizeof(struct pglist_data));
 346         NODE_DATA(0)->bdata = &node0_bdata;
 347         setup_bootmem_allocator();
 348         return max_low_pfn;
 349 }
 350
 351 void __init zone_sizes_init(void)
 352 {
 353         int nid;
 354
 355         /*
 356          * Insert nodes into pgdat_list backward so they appear in order.
 357          * Clobber node 0's links and NULL out pgdat_list before starting.
 358          */
 359         pgdat_list = NULL;
 360         for (nid = MAX_NUMNODES - 1; nid >= 0; nid--) {
 361                 if (!node_online(nid))
 362                         continue;
 363                 NODE_DATA(nid)->pgdat_next = pgdat_list;
 364                 pgdat_list = NODE_DATA(nid);
 365         }
 366
 367         for_each_online_node(nid) {
 368                 unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
 369                 unsigned long *zholes_size;
 370                 unsigned int max_dma;
 371
 372                 unsigned long low = max_low_pfn;
 373                 unsigned long start = node_start_pfn[nid];
 374                 unsigned long high = node_end_pfn[nid];
 375
 376                 max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 377
 378                 if (node_has_online_mem(nid)){
 379                         if (start > low) {
 380 #ifdef CONFIG_HIGHMEM
 381                                 BUG_ON(start > high);
 382                                 zones_size[ZONE_HIGHMEM] = high - start;
 383 #endif
 384                         } else {
 385                                 if (low < max_dma)
 386                                         zones_size[ZONE_DMA] = low;
 387                                 else {
 388                                         BUG_ON(max_dma > low);
 389                                         BUG_ON(low > high);
 390                                         zones_size[ZONE_DMA] = max_dma;
 391                                         zones_size[ZONE_NORMAL] = low - max_dma;
 392 #ifdef CONFIG_HIGHMEM
 393                                         zones_size[ZONE_HIGHMEM] = high - low;
 394 #endif
 395                                 }
 396                         }
 397                 }
 398
 399                 zholes_size = get_zholes_size(nid);
 400
 401                 free_area_init_node(nid, NODE_DATA(nid), zones_size, start,
 402                                 zholes_size);
 403         }
 404         return;
 405 }
 406
 407 void __init set_highmem_pages_init(int bad_ppro)
 408 {
 409 #ifdef CONFIG_HIGHMEM
 410         struct zone *zone;
 411         struct page *page;
 412
 413         for_each_zone(zone) {
 414                 unsigned long node_pfn, zone_start_pfn, zone_end_pfn;
 415
 416                 if (!is_highmem(zone))
 417                         continue;
 418
 419                 zone_start_pfn = zone->zone_start_pfn;
 420                 zone_end_pfn = zone_start_pfn + zone->spanned_pages;
 421
 422                 printk("Initializing %s for node %d (%08lx:%08lx)\n",
 423                                 zone->name, zone->zone_pgdat->node_id,
 424                                 zone_start_pfn, zone_end_pfn);
 425
 426                 for (node_pfn = zone_start_pfn; node_pfn < zone_end_pfn; node_pfn++) {
 427                         if (!pfn_valid(node_pfn))
 428                                 continue;
 429                         page = pfn_to_page(node_pfn);
 430                         add_one_highpage_init(page, node_pfn, bad_ppro);
 431                 }
 432         }
 433         totalram_pages += totalhigh_pages;
 434 #endif
 435 }