arch/arm/mm/init.c

   1 /*
   2  *  linux/arch/arm/mm/init.c
   3  *
   4  *  Copyright (C) 1995-2005 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/errno.h>
  12 #include <linux/ptrace.h>
  13 #include <linux/swap.h>
  14 #include <linux/init.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/mman.h>
  17 #include <linux/nodemask.h>
  18 #include <linux/initrd.h>
  19
  20 #include <asm/mach-types.h>
  21 #include <asm/setup.h>
  22 #include <asm/sizes.h>
  23 #include <asm/tlb.h>
  24
  25 #include <asm/mach/arch.h>
  26 #include <asm/mach/map.h>
  27
  28 #include "mm.h"
  29
  30 extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
  31 extern unsigned long phys_initrd_start;
  32 extern unsigned long phys_initrd_size;
  33
  34 /*
  35  * The sole use of this is to pass memory configuration
  36  * data from paging_init to mem_init.
  37  */
  38 static struct meminfo meminfo __initdata = { 0, };
  39
  40 void show_mem(void)
  41 {
  42         int free = 0, total = 0, reserved = 0;
  43         int shared = 0, cached = 0, slab = 0, node;
  44
  45         printk("Mem-info:\n");
  46         show_free_areas();
  47         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
  48
  49         for_each_online_node(node) {
  50                 struct page *page, *end;
  51
  52                 page = NODE_MEM_MAP(node);
  53                 end  = page + NODE_DATA(node)->node_spanned_pages;
  54
  55                 do {
  56                         total++;
  57                         if (PageReserved(page))
  58                                 reserved++;
  59                         else if (PageSwapCache(page))
  60                                 cached++;
  61                         else if (PageSlab(page))
  62                                 slab++;
  63                         else if (!page_count(page))
  64                                 free++;
  65                         else
  66                                 shared += page_count(page) - 1;
  67                         page++;
  68                 } while (page < end);
  69         }
  70
  71         printk("%d pages of RAM\n", total);
  72         printk("%d free pages\n", free);
  73         printk("%d reserved pages\n", reserved);
  74         printk("%d slab pages\n", slab);
  75         printk("%d pages shared\n", shared);
  76         printk("%d pages swap cached\n", cached);
  77 }
  78
  79 #define for_each_nodebank(iter,mi,no)                   \
  80         for (iter = 0; iter < mi->nr_banks; iter++)     \
  81                 if (mi->bank[iter].node == no)
  82
  83 /*
  84  * FIXME: We really want to avoid allocating the bootmap bitmap
  85  * over the top of the initrd.  Hopefully, this is located towards
  86  * the start of a bank, so if we allocate the bootmap bitmap at
  87  * the end, we won't clash.
  88  */
  89 static unsigned int __init
  90 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
  91 {
  92         unsigned int start_pfn, bank, bootmap_pfn;
  93
  94         start_pfn   = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
  95         bootmap_pfn = 0;
  96
  97         for_each_nodebank(bank, mi, node) {
  98                 unsigned int start, end;
  99
 100                 start = mi->bank[bank].start >> PAGE_SHIFT;
 101                 end   = (mi->bank[bank].size +
 102                          mi->bank[bank].start) >> PAGE_SHIFT;
 103
 104                 if (end < start_pfn)
 105                         continue;
 106
 107                 if (start < start_pfn)
 108                         start = start_pfn;
 109
 110                 if (end <= start)
 111                         continue;
 112
 113                 if (end - start >= bootmap_pages) {
 114                         bootmap_pfn = start;
 115                         break;
 116                 }
 117         }
 118
 119         if (bootmap_pfn == 0)
 120                 BUG();
 121
 122         return bootmap_pfn;
 123 }
 124
 125 static int __init check_initrd(struct meminfo *mi)
 126 {
 127         int initrd_node = -2;
 128 #ifdef CONFIG_BLK_DEV_INITRD
 129         unsigned long end = phys_initrd_start + phys_initrd_size;
 130
 131         /*
 132          * Make sure that the initrd is within a valid area of
 133          * memory.
 134          */
 135         if (phys_initrd_size) {
 136                 unsigned int i;
 137
 138                 initrd_node = -1;
 139
 140                 for (i = 0; i < mi->nr_banks; i++) {
 141                         unsigned long bank_end;
 142
 143                         bank_end = mi->bank[i].start + mi->bank[i].size;
 144
 145                         if (mi->bank[i].start <= phys_initrd_start &&
 146                             end <= bank_end)
 147                                 initrd_node = mi->bank[i].node;
 148                 }
 149         }
 150
 151         if (initrd_node == -1) {
 152                 printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
 153                        "physical memory - disabling initrd\n",
 154                        phys_initrd_start, end);
 155                 phys_initrd_start = phys_initrd_size = 0;
 156         }
 157 #endif
 158
 159         return initrd_node;
 160 }
 161
 162 static inline void map_memory_bank(struct membank *bank)
 163 {
 164 #ifdef CONFIG_MMU
 165         struct map_desc map;
 166
 167         map.pfn = __phys_to_pfn(bank->start);
 168         map.virtual = __phys_to_virt(bank->start);
 169         map.length = bank->size;
 170         map.type = MT_MEMORY;
 171
 172         create_mapping(&map);
 173 #endif
 174 }
 175
 176 static unsigned long __init
 177 bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
 178 {
 179         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 180         unsigned long start_pfn, end_pfn, boot_pfn;
 181         unsigned int boot_pages;
 182         pg_data_t *pgdat;
 183         int i;
 184
 185         start_pfn = -1UL;
 186         end_pfn = 0;
 187
 188         /*
 189          * Calculate the pfn range, and map the memory banks for this node.
 190          */
 191         for_each_nodebank(i, mi, node) {
 192                 struct membank *bank = &mi->bank[i];
 193                 unsigned long start, end;
 194
 195                 start = bank->start >> PAGE_SHIFT;
 196                 end = (bank->start + bank->size) >> PAGE_SHIFT;
 197
 198                 if (start_pfn > start)
 199                         start_pfn = start;
 200                 if (end_pfn < end)
 201                         end_pfn = end;
 202
 203                 map_memory_bank(bank);
 204         }
 205
 206         /*
 207          * If there is no memory in this node, ignore it.
 208          */
 209         if (end_pfn == 0)
 210                 return end_pfn;
 211
 212         /*
 213          * Allocate the bootmem bitmap page.
 214          */
 215         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 216         boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
 217
 218         /*
 219          * Initialise the bootmem allocator for this node, handing the
 220          * memory banks over to bootmem.
 221          */
 222         node_set_online(node);
 223         pgdat = NODE_DATA(node);
 224         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 225
 226         for_each_nodebank(i, mi, node)
 227                 free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);
 228
 229         /*
 230          * Reserve the bootmem bitmap for this node.
 231          */
 232         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 233                              boot_pages << PAGE_SHIFT);
 234
 235 #ifdef CONFIG_BLK_DEV_INITRD
 236         /*
 237          * If the initrd is in this node, reserve its memory.
 238          */
 239         if (node == initrd_node) {
 240                 reserve_bootmem_node(pgdat, phys_initrd_start,
 241                                      phys_initrd_size);
 242                 initrd_start = __phys_to_virt(phys_initrd_start);
 243                 initrd_end = initrd_start + phys_initrd_size;
 244         }
 245 #endif
 246
 247         /*
 248          * Finally, reserve any node zero regions.
 249          */
 250         if (node == 0)
 251                 reserve_node_zero(pgdat);
 252
 253         /*
 254          * initialise the zones within this node.
 255          */
 256         memset(zone_size, 0, sizeof(zone_size));
 257         memset(zhole_size, 0, sizeof(zhole_size));
 258
 259         /*
 260          * The size of this node has already been determined.  If we need
 261          * to do anything fancy with the allocation of this memory to the
 262          * zones, now is the time to do it.
 263          */
 264         zone_size[0] = end_pfn - start_pfn;
 265
 266         /*
 267          * For each bank in this node, calculate the size of the holes.
 268          *  holes = node_size - sum(bank_sizes_in_node)
 269          */
 270         zhole_size[0] = zone_size[0];
 271         for_each_nodebank(i, mi, node)
 272                 zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
 273
 274         /*
 275          * Adjust the sizes according to any special requirements for
 276          * this machine type.
 277          */
 278         arch_adjust_zones(node, zone_size, zhole_size);
 279
 280         free_area_init_node(node, pgdat, zone_size, start_pfn, zhole_size);
 281
 282         return end_pfn;
 283 }
 284
 285 void __init bootmem_init(struct meminfo *mi)
 286 {
 287         unsigned long memend_pfn = 0;
 288         int node, initrd_node, i;
 289
 290         /*
 291          * Invalidate the node number for empty or invalid memory banks
 292          */
 293         for (i = 0; i < mi->nr_banks; i++)
 294                 if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
 295                         mi->bank[i].node = -1;
 296
 297         memcpy(&meminfo, mi, sizeof(meminfo));
 298
 299         /*
 300          * Locate which node contains the ramdisk image, if any.
 301          */
 302         initrd_node = check_initrd(mi);
 303
 304         /*
 305          * Run through each node initialising the bootmem allocator.
 306          */
 307         for_each_node(node) {
 308                 unsigned long end_pfn;
 309
 310                 end_pfn = bootmem_init_node(node, initrd_node, mi);
 311
 312                 /*
 313                  * Remember the highest memory PFN.
 314                  */
 315                 if (end_pfn > memend_pfn)
 316                         memend_pfn = end_pfn;
 317         }
 318
 319         high_memory = __va(memend_pfn << PAGE_SHIFT);
 320
 321         /*
 322          * This doesn't seem to be used by the Linux memory manager any
 323          * more, but is used by ll_rw_block.  If we can get rid of it, we
 324          * also get rid of some of the stuff above as well.
 325          *
 326          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 327          * the system, not the maximum PFN.
 328          */
 329         max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 330 }
 331
 332 static inline void free_area(unsigned long addr, unsigned long end, char *s)
 333 {
 334         unsigned int size = (end - addr) >> 10;
 335
 336         for (; addr < end; addr += PAGE_SIZE) {
 337                 struct page *page = virt_to_page(addr);
 338                 ClearPageReserved(page);
 339                 init_page_count(page);
 340                 free_page(addr);
 341                 totalram_pages++;
 342         }
 343
 344         if (size && s)
 345                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 346 }
 347
 348 static inline void
 349 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 350 {
 351         struct page *start_pg, *end_pg;
 352         unsigned long pg, pgend;
 353
 354         /*
 355          * Convert start_pfn/end_pfn to a struct page pointer.
 356          */
 357         start_pg = pfn_to_page(start_pfn);
 358         end_pg = pfn_to_page(end_pfn);
 359
 360         /*
 361          * Convert to physical addresses, and
 362          * round start upwards and end downwards.
 363          */
 364         pg = PAGE_ALIGN(__pa(start_pg));
 365         pgend = __pa(end_pg) & PAGE_MASK;
 366
 367         /*
 368          * If there are free pages between these,
 369          * free the section of the memmap array.
 370          */
 371         if (pg < pgend)
 372                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 373 }
 374
 375 /*
 376  * The mem_map array can get very big.  Free the unused area of the memory map.
 377  */
 378 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 379 {
 380         unsigned long bank_start, prev_bank_end = 0;
 381         unsigned int i;
 382
 383         /*
 384          * [FIXME] This relies on each bank being in address order.  This
 385          * may not be the case, especially if the user has provided the
 386          * information on the command line.
 387          */
 388         for_each_nodebank(i, mi, node) {
 389                 bank_start = mi->bank[i].start >> PAGE_SHIFT;
 390                 if (bank_start < prev_bank_end) {
 391                         printk(KERN_ERR "MEM: unordered memory banks.  "
 392                                 "Not freeing memmap.\n");
 393                         break;
 394                 }
 395
 396                 /*
 397                  * If we had a previous bank, and there is a space
 398                  * between the current bank and the previous, free it.
 399                  */
 400                 if (prev_bank_end && prev_bank_end != bank_start)
 401                         free_memmap(node, prev_bank_end, bank_start);
 402
 403                 prev_bank_end = (mi->bank[i].start +
 404                                  mi->bank[i].size) >> PAGE_SHIFT;
 405         }
 406 }
 407
 408 /*
 409  * mem_init() marks the free areas in the mem_map and tells us how much
 410  * memory is free.  This is done after various parts of the system have
 411  * claimed their memory after the kernel image.
 412  */
 413 void __init mem_init(void)
 414 {
 415         unsigned int codepages, datapages, initpages;
 416         int i, node;
 417
 418         codepages = &_etext - &_text;
 419         datapages = &_end - &__data_start;
 420         initpages = &__init_end - &__init_begin;
 421
 422 #ifndef CONFIG_DISCONTIGMEM
 423         max_mapnr   = virt_to_page(high_memory) - mem_map;
 424 #endif
 425
 426         /* this will put all unused low memory onto the freelists */
 427         for_each_online_node(node) {
 428                 pg_data_t *pgdat = NODE_DATA(node);
 429
 430                 free_unused_memmap_node(node, &meminfo);
 431
 432                 if (pgdat->node_spanned_pages != 0)
 433                         totalram_pages += free_all_bootmem_node(pgdat);
 434         }
 435
 436 #ifdef CONFIG_SA1111
 437         /* now that our DMA memory is actually so designated, we can free it */
 438         free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
 439 #endif
 440
 441         /*
 442          * Since our memory may not be contiguous, calculate the
 443          * real number of pages we have in this system
 444          */
 445         printk(KERN_INFO "Memory:");
 446
 447         num_physpages = 0;
 448         for (i = 0; i < meminfo.nr_banks; i++) {
 449                 num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
 450                 printk(" %ldMB", meminfo.bank[i].size >> 20);
 451         }
 452
 453         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 454         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 455                 "%dK data, %dK init)\n",
 456                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 457                 codepages >> 10, datapages >> 10, initpages >> 10);
 458
 459         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 460                 extern int sysctl_overcommit_memory;
 461                 /*
 462                  * On a machine this small we won't get
 463                  * anywhere without overcommit, so turn
 464                  * it on by default.
 465                  */
 466                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 467         }
 468 }
 469
 470 void free_initmem(void)
 471 {
 472         if (!machine_is_integrator() && !machine_is_cintegrator()) {
 473                 free_area((unsigned long)(&__init_begin),
 474                           (unsigned long)(&__init_end),
 475                           "init");
 476         }
 477 }
 478
 479 #ifdef CONFIG_BLK_DEV_INITRD
 480
 481 static int keep_initrd;
 482
 483 void free_initrd_mem(unsigned long start, unsigned long end)
 484 {
 485         if (!keep_initrd)
 486                 free_area(start, end, "initrd");
 487 }
 488
 489 static int __init keepinitrd_setup(char *__unused)
 490 {
 491         keep_initrd = 1;
 492         return 1;
 493 }
 494
 495 __setup("keepinitrd", keepinitrd_setup);
 496 #endif