Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 | /*
* linux/arch/arm/mm/init.c
*
* Copyright (C) 1995-2000 Russell King
*/
#include <linux/config.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/ptrace.h>
#include <linux/mman.h>
#include <linux/mm.h>
#include <linux/swap.h>
#include <linux/swapctl.h>
#include <linux/smp.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#ifdef CONFIG_BLK_DEV_INITRD
#include <linux/blk.h>
#endif
#include <asm/system.h>
#include <asm/segment.h>
#include <asm/pgalloc.h>
#include <asm/dma.h>
#include <asm/hardware.h>
#include <asm/setup.h>
#include "map.h"
#ifndef CONFIG_DISCONTIGMEM
#define NR_NODES 1
#else
#define NR_NODES 4
#endif
#ifdef CONFIG_CPU_32
#define TABLE_OFFSET (PTRS_PER_PTE)
#else
#define TABLE_OFFSET 0
#endif
#define TABLE_SIZE ((TABLE_OFFSET + PTRS_PER_PTE) * sizeof(void *))
static unsigned long totalram_pages;
pgd_t swapper_pg_dir[PTRS_PER_PGD];
extern char _stext, _text, _etext, _end, __init_begin, __init_end;
/*
* The sole use of this is to pass memory configuration
* data from paging_init to mem_init.
*/
static struct meminfo __initdata meminfo;
/*
* empty_bad_page is the page that is used for page faults when
* linux is out-of-memory. Older versions of linux just did a
* do_exit(), but using this instead means there is less risk
* for a process dying in kernel mode, possibly leaving a inode
* unused etc..
*
* empty_bad_pte_table is the accompanying page-table: it is
* initialized to point to BAD_PAGE entries.
*
* empty_zero_page is a special page that is used for
* zero-initialized data and COW.
*/
struct page *empty_zero_page;
struct page *empty_bad_page;
pte_t *empty_bad_pte_table;
pte_t *get_bad_pte_table(void)
{
pte_t v;
int i;
v = pte_mkdirty(mk_pte(empty_bad_page, PAGE_SHARED));
for (i = 0; i < PTRS_PER_PTE; i++)
set_pte(empty_bad_pte_table + i, v);
return empty_bad_pte_table;
}
void __handle_bad_pmd(pmd_t *pmd)
{
pmd_ERROR(*pmd);
#ifdef CONFIG_DEBUG_ERRORS
__backtrace();
#endif
set_pmd(pmd, mk_user_pmd(get_bad_pte_table()));
}
void __handle_bad_pmd_kernel(pmd_t *pmd)
{
pmd_ERROR(*pmd);
#ifdef CONFIG_DEBUG_ERRORS
__backtrace();
#endif
set_pmd(pmd, mk_kernel_pmd(get_bad_pte_table()));
}
#ifndef CONFIG_NO_PGT_CACHE
struct pgtable_cache_struct quicklists;
int do_check_pgt_cache(int low, int high)
{
int freed = 0;
if(pgtable_cache_size > high) {
do {
if(pgd_quicklist) {
free_pgd_slow(get_pgd_fast());
freed++;
}
if(pmd_quicklist) {
free_pmd_slow(get_pmd_fast());
freed++;
}
if(pte_quicklist) {
free_pte_slow(get_pte_fast());
freed++;
}
} while(pgtable_cache_size > low);
}
return freed;
}
#else
int do_check_pgt_cache(int low, int high)
{
return 0;
}
#endif
void show_mem(void)
{
int free = 0, total = 0, reserved = 0;
int shared = 0, cached = 0, node;
printk("Mem-info:\n");
show_free_areas();
printk("Free swap: %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
for (node = 0; node < numnodes; node++) {
struct page *page, *end;
page = NODE_MEM_MAP(node);
end = page + NODE_DATA(node)->node_size;
do {
if (PageSkip(page)) {
page = page->next_hash;
if (page == NULL)
break;
}
total++;
if (PageReserved(page))
reserved++;
else if (PageSwapCache(page))
cached++;
else if (!page_count(page))
free++;
else
shared += atomic_read(&page->count) - 1;
page++;
} while (page < end);
}
printk("%d pages of RAM\n", total);
printk("%d free pages\n", free);
printk("%d reserved pages\n", reserved);
printk("%d pages shared\n", shared);
printk("%d pages swap cached\n", cached);
#ifndef CONFIG_NO_PGT_CACHE
printk("%ld page tables cached\n", pgtable_cache_size);
#endif
show_buffers();
}
struct node_info {
unsigned int start;
unsigned int end;
int bootmap_pages;
};
#define O_PFN_DOWN(x) ((x) >> PAGE_SHIFT)
#define V_PFN_DOWN(x) O_PFN_DOWN(__pa(x))
#define O_PFN_UP(x) (PAGE_ALIGN(x) >> PAGE_SHIFT)
#define V_PFN_UP(x) O_PFN_UP(__pa(x))
#define PFN_SIZE(x) ((x) >> PAGE_SHIFT)
#define PFN_RANGE(s,e) PFN_SIZE(PAGE_ALIGN((unsigned long)(e)) - \
(((unsigned long)(s)) & PAGE_MASK))
/*
* FIXME: We really want to avoid allocating the bootmap bitmap
* over the top of the initrd. Hopefully, this is located towards
* the start of a bank, so if we allocate the bootmap bitmap at
* the end, we won't clash.
*/
static unsigned int __init
find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
{
unsigned int start_pfn, bank, bootmap_pfn;
start_pfn = V_PFN_UP(&_end);
bootmap_pfn = 0;
for (bank = 0; bank < mi->nr_banks; bank ++) {
unsigned int start, end;
if (mi->bank[bank].node != node)
continue;
start = O_PFN_UP(mi->bank[bank].start);
end = O_PFN_DOWN(mi->bank[bank].size +
mi->bank[bank].start);
if (end < start_pfn)
continue;
if (start < start_pfn)
start = start_pfn;
if (end <= start)
continue;
if (end - start >= bootmap_pages) {
bootmap_pfn = start;
break;
}
}
if (bootmap_pfn == 0)
BUG();
return bootmap_pfn;
}
/*
* Scan the memory info structure and pull out:
* - the end of memory
* - the number of nodes
* - the pfn range of each node
* - the number of bootmem bitmap pages
*/
static unsigned int __init
find_memend_and_nodes(struct meminfo *mi, struct node_info *np)
{
unsigned int i, bootmem_pages = 0, memend_pfn = 0;
for (i = 0; i < NR_NODES; i++) {
np[i].start = -1U;
np[i].end = 0;
np[i].bootmap_pages = 0;
}
for (i = 0; i < mi->nr_banks; i++) {
unsigned long start, end;
int node;
if (mi->bank[i].size == 0) {
/*
* Mark this bank with an invalid node number
*/
mi->bank[i].node = -1;
continue;
}
node = mi->bank[i].node;
if (node >= numnodes) {
numnodes = node + 1;
/*
* Make sure we haven't exceeded the maximum number
* of nodes that we have in this configuration. If
* we have, we're in trouble. (maybe we ought to
* limit, instead of bugging?)
*/
if (numnodes > NR_NODES)
BUG();
}
/*
* Get the start and end pfns for this bank
*/
start = O_PFN_UP(mi->bank[i].start);
end = O_PFN_DOWN(mi->bank[i].start + mi->bank[i].size);
if (np[node].start > start)
np[node].start = start;
if (np[node].end < end)
np[node].end = end;
if (memend_pfn < end)
memend_pfn = end;
}
/*
* Calculate the number of pages we require to
* store the bootmem bitmaps.
*/
for (i = 0; i < numnodes; i++) {
if (np[i].end == 0)
continue;
np[i].bootmap_pages = bootmem_bootmap_pages(np[i].end -
np[i].start);
bootmem_pages += np[i].bootmap_pages;
}
/*
* This doesn't seem to be used by the Linux memory
* manager any more. If we can get rid of it, we
* also get rid of some of the stuff above as well.
*/
max_low_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
mi->end = memend_pfn << PAGE_SHIFT;
return bootmem_pages;
}
static int __init check_initrd(struct meminfo *mi)
{
int initrd_node = -2;
#ifdef CONFIG_BLK_DEV_INITRD
/*
* Make sure that the initrd is within a valid area of
* memory.
*/
if (initrd_start) {
unsigned long phys_initrd_start, phys_initrd_end;
unsigned int i;
phys_initrd_start = __pa(initrd_start);
phys_initrd_end = __pa(initrd_end);
for (i = 0; i < mi->nr_banks; i++) {
unsigned long bank_end;
bank_end = mi->bank[i].start + mi->bank[i].size;
if (mi->bank[i].start <= phys_initrd_start &&
phys_initrd_end <= bank_end)
initrd_node = mi->bank[i].node;
}
}
if (initrd_node == -1) {
printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
"physical memory - disabling initrd\n",
initrd_start, initrd_end);
initrd_start = initrd_end = 0;
}
#endif
return initrd_node;
}
/*
* Reserve the various regions of node 0
*/
static inline void reserve_node_zero(unsigned int bootmap_pfn, unsigned int bootmap_pages)
{
/*
* Register the kernel text and data with bootmem.
* Note that this can only be in node 0.
*/
reserve_bootmem_node(0, __pa(&_stext), &_end - &_stext);
#ifdef CONFIG_CPU_32
/*
* Reserve the page tables. These are already in use,
* and can only be in node 0.
*/
reserve_bootmem_node(0, __pa(swapper_pg_dir),
PTRS_PER_PGD * sizeof(void *));
#endif
/*
* And don't forget to reserve the allocator bitmap,
* which will be freed later.
*/
reserve_bootmem_node(0, bootmap_pfn << PAGE_SHIFT,
bootmap_pages << PAGE_SHIFT);
}
/*
* Register all available RAM in this node with the bootmem allocator.
*/
static inline void free_bootmem_node_bank(int node, struct meminfo *mi)
{
int bank;
for (bank = 0; bank < mi->nr_banks; bank++)
if (mi->bank[bank].node == node)
free_bootmem_node(node, mi->bank[bank].start,
mi->bank[bank].size);
}
/*
* Initialise the bootmem allocator for all nodes. This is called
* early during the architecture specific initialisation.
*/
void __init bootmem_init(struct meminfo *mi)
{
struct node_info node_info[NR_NODES], *np = node_info;
unsigned int bootmap_pages, bootmap_pfn, map_pg;
int node, initrd_node;
bootmap_pages = find_memend_and_nodes(mi, np);
bootmap_pfn = find_bootmap_pfn(0, mi, bootmap_pages);
initrd_node = check_initrd(mi);
map_pg = bootmap_pfn;
for (node = 0; node < numnodes; node++, np++) {
/*
* If there are no pages in this node, ignore it.
* Note that node 0 must always have some pages.
*/
if (np->end == 0) {
if (node == 0)
BUG();
continue;
}
/*
* Initialise the bootmem allocator.
*/
init_bootmem_node(node, map_pg, np->start, np->end);
free_bootmem_node_bank(node, mi);
map_pg += np->bootmap_pages;
/*
* If this is node 0, we need to reserve some areas ASAP -
* we may use bootmem on node 0 to setup the other nodes.
*/
if (node == 0)
reserve_node_zero(bootmap_pfn, bootmap_pages);
}
#ifdef CONFIG_BLK_DEV_INITRD
if (initrd_node >= 0)
reserve_bootmem_node(initrd_node, __pa(initrd_start),
initrd_end - initrd_start);
#endif
if (map_pg != bootmap_pfn + bootmap_pages)
BUG();
}
/*
* paging_init() sets up the page tables, initialises the zone memory
* maps, and sets up the zero page, bad page and bad page tables.
*/
void __init paging_init(struct meminfo *mi)
{
void *zero_page, *bad_page, *bad_table;
int node;
memcpy(&meminfo, mi, sizeof(meminfo));
/*
* allocate what we need for the bad pages
*/
zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
bad_page = alloc_bootmem_low_pages(PAGE_SIZE);
bad_table = alloc_bootmem_low_pages(TABLE_SIZE);
/*
* initialise the page tables
*/
pagetable_init(mi);
flush_tlb_all();
/*
* initialise the zones within each node
*/
for (node = 0; node < numnodes; node++) {
unsigned long zone_size[MAX_NR_ZONES];
unsigned long zhole_size[MAX_NR_ZONES];
struct bootmem_data *bdata;
pg_data_t *pgdat;
int i;
/*
* Initialise the zone size information.
*/
for (i = 0; i < MAX_NR_ZONES; i++) {
zone_size[i] = 0;
zhole_size[i] = 0;
}
pgdat = NODE_DATA(node);
bdata = pgdat->bdata;
/*
* The size of this node has already been determined.
* If we need to do anything fancy with the allocation
* of this memory to the zones, now is the time to do
* it.
*/
zone_size[0] = bdata->node_low_pfn -
(bdata->node_boot_start >> PAGE_SHIFT);
/*
* For each bank in this node, calculate the size of the
* holes. holes = node_size - sum(bank_sizes_in_node)
*/
zhole_size[0] = zone_size[0];
for (i = 0; i < mi->nr_banks; i++) {
if (mi->bank[i].node != node)
continue;
zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
}
free_area_init_node(node, pgdat, zone_size,
bdata->node_boot_start, zhole_size);
}
/*
* finish off the bad pages once
* the mem_map is initialised
*/
memzero(zero_page, PAGE_SIZE);
memzero(bad_page, PAGE_SIZE);
empty_zero_page = mem_map + MAP_NR(zero_page);
empty_bad_page = mem_map + MAP_NR(bad_page);
empty_bad_pte_table = ((pte_t *)bad_table) + TABLE_OFFSET;
}
/*
* mem_init() marks the free areas in the mem_map and tells us how much
* memory is free. This is done after various parts of the system have
* claimed their memory after the kernel image.
*/
void __init mem_init(void)
{
unsigned int codepages, datapages, initpages;
int i, node;
codepages = &_etext - &_text;
datapages = &_end - &_etext;
initpages = &__init_end - &__init_begin;
high_memory = (void *)__va(meminfo.end);
max_mapnr = MAP_NR(high_memory);
/*
* We may have non-contiguous memory.
*/
if (meminfo.nr_banks != 1)
create_memmap_holes(&meminfo);
/* this will put all unused low memory onto the freelists */
for (node = 0; node < numnodes; node++)
totalram_pages += free_all_bootmem_node(node);
/*
* Since our memory may not be contiguous, calculate the
* real number of pages we have in this system
*/
printk(KERN_INFO "Memory:");
num_physpages = 0;
for (i = 0; i < meminfo.nr_banks; i++) {
num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
printk(" %ldMB", meminfo.bank[i].size >> 20);
}
printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
"%dK data, %dK init)\n",
(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
codepages >> 10, datapages >> 10, initpages >> 10);
if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
extern int sysctl_overcommit_memory;
/*
* On a machine this small we won't get
* anywhere without overcommit, so turn
* it on by default.
*/
sysctl_overcommit_memory = 1;
}
}
static inline void free_area(unsigned long addr, unsigned long end, char *s)
{
unsigned int size = (end - addr) >> 10;
struct page *page = mem_map + MAP_NR(addr);
for (; addr < end; addr += PAGE_SIZE, page ++) {
ClearPageReserved(page);
set_page_count(page, 1);
free_page(addr);
totalram_pages++;
}
if (size)
printk(" %dk %s", size, s);
}
void free_initmem(void)
{
printk("Freeing unused kernel memory:");
free_area((unsigned long)(&__init_begin),
(unsigned long)(&__init_end),
"init");
printk("\n");
}
#ifdef CONFIG_BLK_DEV_INITRD
void free_initrd_mem(unsigned long start, unsigned long end)
{
unsigned long addr;
for (addr = start; addr < end; addr += PAGE_SIZE) {
ClearPageReserved(mem_map + MAP_NR(addr));
set_page_count(mem_map+MAP_NR(addr), 1);
free_page(addr);
totalram_pages++;
}
printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
}
#endif
void si_meminfo(struct sysinfo *val)
{
val->totalram = totalram_pages;
val->sharedram = 0;
val->freeram = nr_free_pages();
val->bufferram = atomic_read(&buffermem_pages);
val->totalhigh = 0;
val->freehigh = 0;
val->mem_unit = PAGE_SIZE;
}
|