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/swap.h>
  13 #include <linux/init.h>
  14 #include <linux/bootmem.h>
  15 #include <linux/mman.h>
  16 #include <linux/nodemask.h>
  17 #include <linux/initrd.h>
  18
  19 #include <asm/mach-types.h>
  20 #include <asm/setup.h>
  21 #include <asm/sizes.h>
  22 #include <asm/tlb.h>
  23
  24 #include <asm/mach/arch.h>
  25 #include <asm/mach/map.h>
  26
  27 #include "mm.h"
  28
  29 extern void _text, _etext, __data_start, _end, __init_begin, __init_end;
  30 extern unsigned long phys_initrd_start;
  31 extern unsigned long phys_initrd_size;
  32
  33 /*
  34  * This is used to pass memory configuration data from paging_init
  35  * to mem_init, and by show_mem() to skip holes in the memory map.
  36  */
  37 static struct meminfo meminfo = { 0, };
  38
  39 #define for_each_nodebank(iter,mi,no)                   \
  40         for (iter = 0; iter < mi->nr_banks; iter++)     \
  41                 if (mi->bank[iter].node == no)
  42
  43 void show_mem(void)
  44 {
  45         int free = 0, total = 0, reserved = 0;
  46         int shared = 0, cached = 0, slab = 0, node, i;
  47         struct meminfo * mi = &meminfo;
  48
  49         printk("Mem-info:\n");
  50         show_free_areas();
  51         for_each_online_node(node) {
  52                 pg_data_t *n = NODE_DATA(node);
  53                 struct page *map = n->node_mem_map - n->node_start_pfn;
  54
  55                 for_each_nodebank (i,mi,node) {
  56                         unsigned int pfn1, pfn2;
  57                         struct page *page, *end;
  58
  59                         pfn1 = __phys_to_pfn(mi->bank[i].start);
  60                         pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);
  61
  62                         page = map + pfn1;
  63                         end  = map + pfn2;
  64
  65                         do {
  66                                 total++;
  67                                 if (PageReserved(page))
  68                                         reserved++;
  69                                 else if (PageSwapCache(page))
  70                                         cached++;
  71                                 else if (PageSlab(page))
  72                                         slab++;
  73                                 else if (!page_count(page))
  74                                         free++;
  75                                 else
  76                                         shared += page_count(page) - 1;
  77                                 page++;
  78                         } while (page < end);
  79                 }
  80         }
  81
  82         printk("%d pages of RAM\n", total);
  83         printk("%d free pages\n", free);
  84         printk("%d reserved pages\n", reserved);
  85         printk("%d slab pages\n", slab);
  86         printk("%d pages shared\n", shared);
  87         printk("%d pages swap cached\n", cached);
  88 }
  89
  90 /*
  91  * FIXME: We really want to avoid allocating the bootmap bitmap
  92  * over the top of the initrd.  Hopefully, this is located towards
  93  * the start of a bank, so if we allocate the bootmap bitmap at
  94  * the end, we won't clash.
  95  */
  96 static unsigned int __init
  97 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
  98 {
  99         unsigned int start_pfn, bank, bootmap_pfn;
 100
 101         start_pfn   = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
 102         bootmap_pfn = 0;
 103
 104         for_each_nodebank(bank, mi, node) {
 105                 unsigned int start, end;
 106
 107                 start = mi->bank[bank].start >> PAGE_SHIFT;
 108                 end   = (mi->bank[bank].size +
 109                          mi->bank[bank].start) >> PAGE_SHIFT;
 110
 111                 if (end < start_pfn)
 112                         continue;
 113
 114                 if (start < start_pfn)
 115                         start = start_pfn;
 116
 117                 if (end <= start)
 118                         continue;
 119
 120                 if (end - start >= bootmap_pages) {
 121                         bootmap_pfn = start;
 122                         break;
 123                 }
 124         }
 125
 126         if (bootmap_pfn == 0)
 127                 BUG();
 128
 129         return bootmap_pfn;
 130 }
 131
 132 static int __init check_initrd(struct meminfo *mi)
 133 {
 134         int initrd_node = -2;
 135 #ifdef CONFIG_BLK_DEV_INITRD
 136         unsigned long end = phys_initrd_start + phys_initrd_size;
 137
 138         /*
 139          * Make sure that the initrd is within a valid area of
 140          * memory.
 141          */
 142         if (phys_initrd_size) {
 143                 unsigned int i;
 144
 145                 initrd_node = -1;
 146
 147                 for (i = 0; i < mi->nr_banks; i++) {
 148                         unsigned long bank_end;
 149
 150                         bank_end = mi->bank[i].start + mi->bank[i].size;
 151
 152                         if (mi->bank[i].start <= phys_initrd_start &&
 153                             end <= bank_end)
 154                                 initrd_node = mi->bank[i].node;
 155                 }
 156         }
 157
 158         if (initrd_node == -1) {
 159                 printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
 160                        "physical memory - disabling initrd\n",
 161                        phys_initrd_start, end);
 162                 phys_initrd_start = phys_initrd_size = 0;
 163         }
 164 #endif
 165
 166         return initrd_node;
 167 }
 168
 169 static inline void map_memory_bank(struct membank *bank)
 170 {
 171 #ifdef CONFIG_MMU
 172         struct map_desc map;
 173
 174         map.pfn = __phys_to_pfn(bank->start);
 175         map.virtual = __phys_to_virt(bank->start);
 176         map.length = bank->size;
 177         map.type = MT_MEMORY;
 178
 179         create_mapping(&map);
 180 #endif
 181 }
 182
 183 static unsigned long __init
 184 bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
 185 {
 186         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 187         unsigned long start_pfn, end_pfn, boot_pfn;
 188         unsigned int boot_pages;
 189         pg_data_t *pgdat;
 190         int i;
 191
 192         start_pfn = -1UL;
 193         end_pfn = 0;
 194
 195         /*
 196          * Calculate the pfn range, and map the memory banks for this node.
 197          */
 198         for_each_nodebank(i, mi, node) {
 199                 struct membank *bank = &mi->bank[i];
 200                 unsigned long start, end;
 201
 202                 start = bank->start >> PAGE_SHIFT;
 203                 end = (bank->start + bank->size) >> PAGE_SHIFT;
 204
 205                 if (start_pfn > start)
 206                         start_pfn = start;
 207                 if (end_pfn < end)
 208                         end_pfn = end;
 209
 210                 map_memory_bank(bank);
 211         }
 212
 213         /*
 214          * If there is no memory in this node, ignore it.
 215          */
 216         if (end_pfn == 0)
 217                 return end_pfn;
 218
 219         /*
 220          * Allocate the bootmem bitmap page.
 221          */
 222         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 223         boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
 224
 225         /*
 226          * Initialise the bootmem allocator for this node, handing the
 227          * memory banks over to bootmem.
 228          */
 229         node_set_online(node);
 230         pgdat = NODE_DATA(node);
 231         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 232
 233         for_each_nodebank(i, mi, node)
 234                 free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);
 235
 236         /*
 237          * Reserve the bootmem bitmap for this node.
 238          */
 239         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 240                              boot_pages << PAGE_SHIFT, BOOTMEM_DEFAULT);
 241
 242 #ifdef CONFIG_BLK_DEV_INITRD
 243         /*
 244          * If the initrd is in this node, reserve its memory.
 245          */
 246         if (node == initrd_node) {
 247                 reserve_bootmem_node(pgdat, phys_initrd_start,
 248                                      phys_initrd_size, BOOTMEM_DEFAULT);
 249                 initrd_start = __phys_to_virt(phys_initrd_start);
 250                 initrd_end = initrd_start + phys_initrd_size;
 251         }
 252 #endif
 253
 254         /*
 255          * Finally, reserve any node zero regions.
 256          */
 257         if (node == 0)
 258                 reserve_node_zero(pgdat);
 259
 260         /*
 261          * initialise the zones within this node.
 262          */
 263         memset(zone_size, 0, sizeof(zone_size));
 264         memset(zhole_size, 0, sizeof(zhole_size));
 265
 266         /*
 267          * The size of this node has already been determined.  If we need
 268          * to do anything fancy with the allocation of this memory to the
 269          * zones, now is the time to do it.
 270          */
 271         zone_size[0] = end_pfn - start_pfn;
 272
 273         /*
 274          * For each bank in this node, calculate the size of the holes.
 275          *  holes = node_size - sum(bank_sizes_in_node)
 276          */
 277         zhole_size[0] = zone_size[0];
 278         for_each_nodebank(i, mi, node)
 279                 zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
 280
 281         /*
 282          * Adjust the sizes according to any special requirements for
 283          * this machine type.
 284          */
 285         arch_adjust_zones(node, zone_size, zhole_size);
 286
 287         free_area_init_node(node, zone_size, start_pfn, zhole_size);
 288
 289         return end_pfn;
 290 }
 291
 292 void __init bootmem_init(struct meminfo *mi)
 293 {
 294         unsigned long memend_pfn = 0;
 295         int node, initrd_node, i;
 296
 297         /*
 298          * Invalidate the node number for empty or invalid memory banks
 299          */
 300         for (i = 0; i < mi->nr_banks; i++)
 301                 if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
 302                         mi->bank[i].node = -1;
 303
 304         memcpy(&meminfo, mi, sizeof(meminfo));
 305
 306         /*
 307          * Locate which node contains the ramdisk image, if any.
 308          */
 309         initrd_node = check_initrd(mi);
 310
 311         /*
 312          * Run through each node initialising the bootmem allocator.
 313          */
 314         for_each_node(node) {
 315                 unsigned long end_pfn;
 316
 317                 end_pfn = bootmem_init_node(node, initrd_node, mi);
 318
 319                 /*
 320                  * Remember the highest memory PFN.
 321                  */
 322                 if (end_pfn > memend_pfn)
 323                         memend_pfn = end_pfn;
 324         }
 325
 326         high_memory = __va(memend_pfn << PAGE_SHIFT);
 327
 328         /*
 329          * This doesn't seem to be used by the Linux memory manager any
 330          * more, but is used by ll_rw_block.  If we can get rid of it, we
 331          * also get rid of some of the stuff above as well.
 332          *
 333          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 334          * the system, not the maximum PFN.
 335          */
 336         max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 337 }
 338
 339 static inline void free_area(unsigned long addr, unsigned long end, char *s)
 340 {
 341         unsigned int size = (end - addr) >> 10;
 342
 343         for (; addr < end; addr += PAGE_SIZE) {
 344                 struct page *page = virt_to_page(addr);
 345                 ClearPageReserved(page);
 346                 init_page_count(page);
 347                 free_page(addr);
 348                 totalram_pages++;
 349         }
 350
 351         if (size && s)
 352                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 353 }
 354
 355 static inline void
 356 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 357 {
 358         struct page *start_pg, *end_pg;
 359         unsigned long pg, pgend;
 360
 361         /*
 362          * Convert start_pfn/end_pfn to a struct page pointer.
 363          */
 364         start_pg = pfn_to_page(start_pfn);
 365         end_pg = pfn_to_page(end_pfn);
 366
 367         /*
 368          * Convert to physical addresses, and
 369          * round start upwards and end downwards.
 370          */
 371         pg = PAGE_ALIGN(__pa(start_pg));
 372         pgend = __pa(end_pg) & PAGE_MASK;
 373
 374         /*
 375          * If there are free pages between these,
 376          * free the section of the memmap array.
 377          */
 378         if (pg < pgend)
 379                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 380 }
 381
 382 /*
 383  * The mem_map array can get very big.  Free the unused area of the memory map.
 384  */
 385 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 386 {
 387         unsigned long bank_start, prev_bank_end = 0;
 388         unsigned int i;
 389
 390         /*
 391          * [FIXME] This relies on each bank being in address order.  This
 392          * may not be the case, especially if the user has provided the
 393          * information on the command line.
 394          */
 395         for_each_nodebank(i, mi, node) {
 396                 bank_start = mi->bank[i].start >> PAGE_SHIFT;
 397                 if (bank_start < prev_bank_end) {
 398                         printk(KERN_ERR "MEM: unordered memory banks.  "
 399                                 "Not freeing memmap.\n");
 400                         break;
 401                 }
 402
 403                 /*
 404                  * If we had a previous bank, and there is a space
 405                  * between the current bank and the previous, free it.
 406                  */
 407                 if (prev_bank_end && prev_bank_end != bank_start)
 408                         free_memmap(node, prev_bank_end, bank_start);
 409
 410                 prev_bank_end = (mi->bank[i].start +
 411                                  mi->bank[i].size) >> PAGE_SHIFT;
 412         }
 413 }
 414
 415 /*
 416  * mem_init() marks the free areas in the mem_map and tells us how much
 417  * memory is free.  This is done after various parts of the system have
 418  * claimed their memory after the kernel image.
 419  */
 420 void __init mem_init(void)
 421 {
 422         unsigned int codepages, datapages, initpages;
 423         int i, node;
 424
 425         codepages = &_etext - &_text;
 426         datapages = &_end - &__data_start;
 427         initpages = &__init_end - &__init_begin;
 428
 429 #ifndef CONFIG_DISCONTIGMEM
 430         max_mapnr   = virt_to_page(high_memory) - mem_map;
 431 #endif
 432
 433         /* this will put all unused low memory onto the freelists */
 434         for_each_online_node(node) {
 435                 pg_data_t *pgdat = NODE_DATA(node);
 436
 437                 free_unused_memmap_node(node, &meminfo);
 438
 439                 if (pgdat->node_spanned_pages != 0)
 440                         totalram_pages += free_all_bootmem_node(pgdat);
 441         }
 442
 443 #ifdef CONFIG_SA1111
 444         /* now that our DMA memory is actually so designated, we can free it */
 445         free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
 446 #endif
 447
 448         /*
 449          * Since our memory may not be contiguous, calculate the
 450          * real number of pages we have in this system
 451          */
 452         printk(KERN_INFO "Memory:");
 453
 454         num_physpages = 0;
 455         for (i = 0; i < meminfo.nr_banks; i++) {
 456                 num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
 457                 printk(" %ldMB", meminfo.bank[i].size >> 20);
 458         }
 459
 460         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 461         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 462                 "%dK data, %dK init)\n",
 463                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 464                 codepages >> 10, datapages >> 10, initpages >> 10);
 465
 466         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 467                 extern int sysctl_overcommit_memory;
 468                 /*
 469                  * On a machine this small we won't get
 470                  * anywhere without overcommit, so turn
 471                  * it on by default.
 472                  */
 473                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 474         }
 475 }
 476
 477 void free_initmem(void)
 478 {
 479         if (!machine_is_integrator() && !machine_is_cintegrator()) {
 480                 free_area((unsigned long)(&__init_begin),
 481                           (unsigned long)(&__init_end),
 482                           "init");
 483         }
 484 }
 485
 486 #ifdef CONFIG_BLK_DEV_INITRD
 487
 488 static int keep_initrd;
 489
 490 void free_initrd_mem(unsigned long start, unsigned long end)
 491 {
 492         if (!keep_initrd)
 493                 free_area(start, end, "initrd");
 494 }
 495
 496 static int __init keepinitrd_setup(char *__unused)
 497 {
 498         keep_initrd = 1;
 499         return 1;
 500 }
 501
 502 __setup("keepinitrd", keepinitrd_setup);
 503 #endif