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  * This is used to pass memory configuration data from paging_init
  36  * to mem_init, and by show_mem() to skip holes in the memory map.
  37  */
  38 static struct meminfo meminfo = { 0, };
  39
  40 #define for_each_nodebank(iter,mi,no)                   \
  41         for (iter = 0; iter < mi->nr_banks; iter++)     \
  42                 if (mi->bank[iter].node == no)
  43
  44 void show_mem(void)
  45 {
  46         int free = 0, total = 0, reserved = 0;
  47         int shared = 0, cached = 0, slab = 0, node, i;
  48         struct meminfo * mi = &meminfo;
  49
  50         printk("Mem-info:\n");
  51         show_free_areas();
  52         printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
  53
  54         for_each_online_node(node) {
  55                 pg_data_t *n = NODE_DATA(node);
  56                 struct page *map = n->node_mem_map - n->node_start_pfn;
  57
  58                 for_each_nodebank (i,mi,node) {
  59                         unsigned int pfn1, pfn2;
  60                         struct page *page, *end;
  61
  62                         pfn1 = __phys_to_pfn(mi->bank[i].start);
  63                         pfn2 = __phys_to_pfn(mi->bank[i].size + mi->bank[i].start);
  64
  65                         page = map + pfn1;
  66                         end  = map + pfn2;
  67
  68                         do {
  69                                 total++;
  70                                 if (PageReserved(page))
  71                                         reserved++;
  72                                 else if (PageSwapCache(page))
  73                                         cached++;
  74                                 else if (PageSlab(page))
  75                                         slab++;
  76                                 else if (!page_count(page))
  77                                         free++;
  78                                 else
  79                                         shared += page_count(page) - 1;
  80                                 page++;
  81                         } while (page < end);
  82                 }
  83         }
  84
  85         printk("%d pages of RAM\n", total);
  86         printk("%d free pages\n", free);
  87         printk("%d reserved pages\n", reserved);
  88         printk("%d slab pages\n", slab);
  89         printk("%d pages shared\n", shared);
  90         printk("%d pages swap cached\n", cached);
  91 }
  92
  93 /*
  94  * FIXME: We really want to avoid allocating the bootmap bitmap
  95  * over the top of the initrd.  Hopefully, this is located towards
  96  * the start of a bank, so if we allocate the bootmap bitmap at
  97  * the end, we won't clash.
  98  */
  99 static unsigned int __init
 100 find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
 101 {
 102         unsigned int start_pfn, bank, bootmap_pfn;
 103
 104         start_pfn   = PAGE_ALIGN(__pa(&_end)) >> PAGE_SHIFT;
 105         bootmap_pfn = 0;
 106
 107         for_each_nodebank(bank, mi, node) {
 108                 unsigned int start, end;
 109
 110                 start = mi->bank[bank].start >> PAGE_SHIFT;
 111                 end   = (mi->bank[bank].size +
 112                          mi->bank[bank].start) >> PAGE_SHIFT;
 113
 114                 if (end < start_pfn)
 115                         continue;
 116
 117                 if (start < start_pfn)
 118                         start = start_pfn;
 119
 120                 if (end <= start)
 121                         continue;
 122
 123                 if (end - start >= bootmap_pages) {
 124                         bootmap_pfn = start;
 125                         break;
 126                 }
 127         }
 128
 129         if (bootmap_pfn == 0)
 130                 BUG();
 131
 132         return bootmap_pfn;
 133 }
 134
 135 static int __init check_initrd(struct meminfo *mi)
 136 {
 137         int initrd_node = -2;
 138 #ifdef CONFIG_BLK_DEV_INITRD
 139         unsigned long end = phys_initrd_start + phys_initrd_size;
 140
 141         /*
 142          * Make sure that the initrd is within a valid area of
 143          * memory.
 144          */
 145         if (phys_initrd_size) {
 146                 unsigned int i;
 147
 148                 initrd_node = -1;
 149
 150                 for (i = 0; i < mi->nr_banks; i++) {
 151                         unsigned long bank_end;
 152
 153                         bank_end = mi->bank[i].start + mi->bank[i].size;
 154
 155                         if (mi->bank[i].start <= phys_initrd_start &&
 156                             end <= bank_end)
 157                                 initrd_node = mi->bank[i].node;
 158                 }
 159         }
 160
 161         if (initrd_node == -1) {
 162                 printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
 163                        "physical memory - disabling initrd\n",
 164                        phys_initrd_start, end);
 165                 phys_initrd_start = phys_initrd_size = 0;
 166         }
 167 #endif
 168
 169         return initrd_node;
 170 }
 171
 172 static inline void map_memory_bank(struct membank *bank)
 173 {
 174 #ifdef CONFIG_MMU
 175         struct map_desc map;
 176
 177         map.pfn = __phys_to_pfn(bank->start);
 178         map.virtual = __phys_to_virt(bank->start);
 179         map.length = bank->size;
 180         map.type = MT_MEMORY;
 181
 182         create_mapping(&map);
 183 #endif
 184 }
 185
 186 static unsigned long __init
 187 bootmem_init_node(int node, int initrd_node, struct meminfo *mi)
 188 {
 189         unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 190         unsigned long start_pfn, end_pfn, boot_pfn;
 191         unsigned int boot_pages;
 192         pg_data_t *pgdat;
 193         int i;
 194
 195         start_pfn = -1UL;
 196         end_pfn = 0;
 197
 198         /*
 199          * Calculate the pfn range, and map the memory banks for this node.
 200          */
 201         for_each_nodebank(i, mi, node) {
 202                 struct membank *bank = &mi->bank[i];
 203                 unsigned long start, end;
 204
 205                 start = bank->start >> PAGE_SHIFT;
 206                 end = (bank->start + bank->size) >> PAGE_SHIFT;
 207
 208                 if (start_pfn > start)
 209                         start_pfn = start;
 210                 if (end_pfn < end)
 211                         end_pfn = end;
 212
 213                 map_memory_bank(bank);
 214         }
 215
 216         /*
 217          * If there is no memory in this node, ignore it.
 218          */
 219         if (end_pfn == 0)
 220                 return end_pfn;
 221
 222         /*
 223          * Allocate the bootmem bitmap page.
 224          */
 225         boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
 226         boot_pfn = find_bootmap_pfn(node, mi, boot_pages);
 227
 228         /*
 229          * Initialise the bootmem allocator for this node, handing the
 230          * memory banks over to bootmem.
 231          */
 232         node_set_online(node);
 233         pgdat = NODE_DATA(node);
 234         init_bootmem_node(pgdat, boot_pfn, start_pfn, end_pfn);
 235
 236         for_each_nodebank(i, mi, node)
 237                 free_bootmem_node(pgdat, mi->bank[i].start, mi->bank[i].size);
 238
 239         /*
 240          * Reserve the bootmem bitmap for this node.
 241          */
 242         reserve_bootmem_node(pgdat, boot_pfn << PAGE_SHIFT,
 243                              boot_pages << PAGE_SHIFT);
 244
 245 #ifdef CONFIG_BLK_DEV_INITRD
 246         /*
 247          * If the initrd is in this node, reserve its memory.
 248          */
 249         if (node == initrd_node) {
 250                 reserve_bootmem_node(pgdat, phys_initrd_start,
 251                                      phys_initrd_size);
 252                 initrd_start = __phys_to_virt(phys_initrd_start);
 253                 initrd_end = initrd_start + phys_initrd_size;
 254         }
 255 #endif
 256
 257         /*
 258          * Finally, reserve any node zero regions.
 259          */
 260         if (node == 0)
 261                 reserve_node_zero(pgdat);
 262
 263         /*
 264          * initialise the zones within this node.
 265          */
 266         memset(zone_size, 0, sizeof(zone_size));
 267         memset(zhole_size, 0, sizeof(zhole_size));
 268
 269         /*
 270          * The size of this node has already been determined.  If we need
 271          * to do anything fancy with the allocation of this memory to the
 272          * zones, now is the time to do it.
 273          */
 274         zone_size[0] = end_pfn - start_pfn;
 275
 276         /*
 277          * For each bank in this node, calculate the size of the holes.
 278          *  holes = node_size - sum(bank_sizes_in_node)
 279          */
 280         zhole_size[0] = zone_size[0];
 281         for_each_nodebank(i, mi, node)
 282                 zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
 283
 284         /*
 285          * Adjust the sizes according to any special requirements for
 286          * this machine type.
 287          */
 288         arch_adjust_zones(node, zone_size, zhole_size);
 289
 290         free_area_init_node(node, pgdat, zone_size, start_pfn, zhole_size);
 291
 292         return end_pfn;
 293 }
 294
 295 void __init bootmem_init(struct meminfo *mi)
 296 {
 297         unsigned long memend_pfn = 0;
 298         int node, initrd_node, i;
 299
 300         /*
 301          * Invalidate the node number for empty or invalid memory banks
 302          */
 303         for (i = 0; i < mi->nr_banks; i++)
 304                 if (mi->bank[i].size == 0 || mi->bank[i].node >= MAX_NUMNODES)
 305                         mi->bank[i].node = -1;
 306
 307         memcpy(&meminfo, mi, sizeof(meminfo));
 308
 309         /*
 310          * Locate which node contains the ramdisk image, if any.
 311          */
 312         initrd_node = check_initrd(mi);
 313
 314         /*
 315          * Run through each node initialising the bootmem allocator.
 316          */
 317         for_each_node(node) {
 318                 unsigned long end_pfn;
 319
 320                 end_pfn = bootmem_init_node(node, initrd_node, mi);
 321
 322                 /*
 323                  * Remember the highest memory PFN.
 324                  */
 325                 if (end_pfn > memend_pfn)
 326                         memend_pfn = end_pfn;
 327         }
 328
 329         high_memory = __va(memend_pfn << PAGE_SHIFT);
 330
 331         /*
 332          * This doesn't seem to be used by the Linux memory manager any
 333          * more, but is used by ll_rw_block.  If we can get rid of it, we
 334          * also get rid of some of the stuff above as well.
 335          *
 336          * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
 337          * the system, not the maximum PFN.
 338          */
 339         max_pfn = max_low_pfn = memend_pfn - PHYS_PFN_OFFSET;
 340 }
 341
 342 static inline void free_area(unsigned long addr, unsigned long end, char *s)
 343 {
 344         unsigned int size = (end - addr) >> 10;
 345
 346         for (; addr < end; addr += PAGE_SIZE) {
 347                 struct page *page = virt_to_page(addr);
 348                 ClearPageReserved(page);
 349                 init_page_count(page);
 350                 free_page(addr);
 351                 totalram_pages++;
 352         }
 353
 354         if (size && s)
 355                 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
 356 }
 357
 358 static inline void
 359 free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
 360 {
 361         struct page *start_pg, *end_pg;
 362         unsigned long pg, pgend;
 363
 364         /*
 365          * Convert start_pfn/end_pfn to a struct page pointer.
 366          */
 367         start_pg = pfn_to_page(start_pfn);
 368         end_pg = pfn_to_page(end_pfn);
 369
 370         /*
 371          * Convert to physical addresses, and
 372          * round start upwards and end downwards.
 373          */
 374         pg = PAGE_ALIGN(__pa(start_pg));
 375         pgend = __pa(end_pg) & PAGE_MASK;
 376
 377         /*
 378          * If there are free pages between these,
 379          * free the section of the memmap array.
 380          */
 381         if (pg < pgend)
 382                 free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
 383 }
 384
 385 /*
 386  * The mem_map array can get very big.  Free the unused area of the memory map.
 387  */
 388 static void __init free_unused_memmap_node(int node, struct meminfo *mi)
 389 {
 390         unsigned long bank_start, prev_bank_end = 0;
 391         unsigned int i;
 392
 393         /*
 394          * [FIXME] This relies on each bank being in address order.  This
 395          * may not be the case, especially if the user has provided the
 396          * information on the command line.
 397          */
 398         for_each_nodebank(i, mi, node) {
 399                 bank_start = mi->bank[i].start >> PAGE_SHIFT;
 400                 if (bank_start < prev_bank_end) {
 401                         printk(KERN_ERR "MEM: unordered memory banks.  "
 402                                 "Not freeing memmap.\n");
 403                         break;
 404                 }
 405
 406                 /*
 407                  * If we had a previous bank, and there is a space
 408                  * between the current bank and the previous, free it.
 409                  */
 410                 if (prev_bank_end && prev_bank_end != bank_start)
 411                         free_memmap(node, prev_bank_end, bank_start);
 412
 413                 prev_bank_end = (mi->bank[i].start +
 414                                  mi->bank[i].size) >> PAGE_SHIFT;
 415         }
 416 }
 417
 418 /*
 419  * mem_init() marks the free areas in the mem_map and tells us how much
 420  * memory is free.  This is done after various parts of the system have
 421  * claimed their memory after the kernel image.
 422  */
 423 void __init mem_init(void)
 424 {
 425         unsigned int codepages, datapages, initpages;
 426         int i, node;
 427
 428         codepages = &_etext - &_text;
 429         datapages = &_end - &__data_start;
 430         initpages = &__init_end - &__init_begin;
 431
 432 #ifndef CONFIG_DISCONTIGMEM
 433         max_mapnr   = virt_to_page(high_memory) - mem_map;
 434 #endif
 435
 436         /* this will put all unused low memory onto the freelists */
 437         for_each_online_node(node) {
 438                 pg_data_t *pgdat = NODE_DATA(node);
 439
 440                 free_unused_memmap_node(node, &meminfo);
 441
 442                 if (pgdat->node_spanned_pages != 0)
 443                         totalram_pages += free_all_bootmem_node(pgdat);
 444         }
 445
 446 #ifdef CONFIG_SA1111
 447         /* now that our DMA memory is actually so designated, we can free it */
 448         free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
 449 #endif
 450
 451         /*
 452          * Since our memory may not be contiguous, calculate the
 453          * real number of pages we have in this system
 454          */
 455         printk(KERN_INFO "Memory:");
 456
 457         num_physpages = 0;
 458         for (i = 0; i < meminfo.nr_banks; i++) {
 459                 num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
 460                 printk(" %ldMB", meminfo.bank[i].size >> 20);
 461         }
 462
 463         printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
 464         printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
 465                 "%dK data, %dK init)\n",
 466                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
 467                 codepages >> 10, datapages >> 10, initpages >> 10);
 468
 469         if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
 470                 extern int sysctl_overcommit_memory;
 471                 /*
 472                  * On a machine this small we won't get
 473                  * anywhere without overcommit, so turn
 474                  * it on by default.
 475                  */
 476                 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 477         }
 478 }
 479
 480 void free_initmem(void)
 481 {
 482         if (!machine_is_integrator() && !machine_is_cintegrator()) {
 483                 free_area((unsigned long)(&__init_begin),
 484                           (unsigned long)(&__init_end),
 485                           "init");
 486         }
 487 }
 488
 489 #ifdef CONFIG_BLK_DEV_INITRD
 490
 491 static int keep_initrd;
 492
 493 void free_initrd_mem(unsigned long start, unsigned long end)
 494 {
 495         if (!keep_initrd)
 496                 free_area(start, end, "initrd");
 497 }
 498
 499 static int __init keepinitrd_setup(char *__unused)
 500 {
 501         keep_initrd = 1;
 502         return 1;
 503 }
 504
 505 __setup("keepinitrd", keepinitrd_setup);
 506 #endif