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