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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/mm/init.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/mm/init.c')
-rw-r--r--arch/arm/mm/init.c621
1 files changed, 621 insertions, 0 deletions
diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c
new file mode 100644
index 000000000000..41156c5370f7
--- /dev/null
+++ b/arch/arm/mm/init.c
@@ -0,0 +1,621 @@
1/*
2 * linux/arch/arm/mm/init.c
3 *
4 * Copyright (C) 1995-2002 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/config.h>
11#include <linux/kernel.h>
12#include <linux/errno.h>
13#include <linux/ptrace.h>
14#include <linux/swap.h>
15#include <linux/init.h>
16#include <linux/bootmem.h>
17#include <linux/mman.h>
18#include <linux/nodemask.h>
19#include <linux/initrd.h>
20
21#include <asm/mach-types.h>
22#include <asm/hardware.h>
23#include <asm/setup.h>
24#include <asm/tlb.h>
25
26#include <asm/mach/arch.h>
27#include <asm/mach/map.h>
28
29#define TABLE_SIZE (2 * PTRS_PER_PTE * sizeof(pte_t))
30
31DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
32
33extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
34extern void _stext, _text, _etext, __data_start, _end, __init_begin, __init_end;
35extern unsigned long phys_initrd_start;
36extern unsigned long phys_initrd_size;
37
38/*
39 * The sole use of this is to pass memory configuration
40 * data from paging_init to mem_init.
41 */
42static struct meminfo meminfo __initdata = { 0, };
43
44/*
45 * empty_zero_page is a special page that is used for
46 * zero-initialized data and COW.
47 */
48struct page *empty_zero_page;
49
50void show_mem(void)
51{
52 int free = 0, total = 0, reserved = 0;
53 int shared = 0, cached = 0, slab = 0, node;
54
55 printk("Mem-info:\n");
56 show_free_areas();
57 printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
58
59 for_each_online_node(node) {
60 struct page *page, *end;
61
62 page = NODE_MEM_MAP(node);
63 end = page + NODE_DATA(node)->node_spanned_pages;
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 printk("%d pages of RAM\n", total);
82 printk("%d free pages\n", free);
83 printk("%d reserved pages\n", reserved);
84 printk("%d slab pages\n", slab);
85 printk("%d pages shared\n", shared);
86 printk("%d pages swap cached\n", cached);
87}
88
89struct node_info {
90 unsigned int start;
91 unsigned int end;
92 int bootmap_pages;
93};
94
95#define O_PFN_DOWN(x) ((x) >> PAGE_SHIFT)
96#define V_PFN_DOWN(x) O_PFN_DOWN(__pa(x))
97
98#define O_PFN_UP(x) (PAGE_ALIGN(x) >> PAGE_SHIFT)
99#define V_PFN_UP(x) O_PFN_UP(__pa(x))
100
101#define PFN_SIZE(x) ((x) >> PAGE_SHIFT)
102#define PFN_RANGE(s,e) PFN_SIZE(PAGE_ALIGN((unsigned long)(e)) - \
103 (((unsigned long)(s)) & PAGE_MASK))
104
105/*
106 * FIXME: We really want to avoid allocating the bootmap bitmap
107 * over the top of the initrd. Hopefully, this is located towards
108 * the start of a bank, so if we allocate the bootmap bitmap at
109 * the end, we won't clash.
110 */
111static unsigned int __init
112find_bootmap_pfn(int node, struct meminfo *mi, unsigned int bootmap_pages)
113{
114 unsigned int start_pfn, bank, bootmap_pfn;
115
116 start_pfn = V_PFN_UP(&_end);
117 bootmap_pfn = 0;
118
119 for (bank = 0; bank < mi->nr_banks; bank ++) {
120 unsigned int start, end;
121
122 if (mi->bank[bank].node != node)
123 continue;
124
125 start = O_PFN_UP(mi->bank[bank].start);
126 end = O_PFN_DOWN(mi->bank[bank].size +
127 mi->bank[bank].start);
128
129 if (end < start_pfn)
130 continue;
131
132 if (start < start_pfn)
133 start = start_pfn;
134
135 if (end <= start)
136 continue;
137
138 if (end - start >= bootmap_pages) {
139 bootmap_pfn = start;
140 break;
141 }
142 }
143
144 if (bootmap_pfn == 0)
145 BUG();
146
147 return bootmap_pfn;
148}
149
150/*
151 * Scan the memory info structure and pull out:
152 * - the end of memory
153 * - the number of nodes
154 * - the pfn range of each node
155 * - the number of bootmem bitmap pages
156 */
157static unsigned int __init
158find_memend_and_nodes(struct meminfo *mi, struct node_info *np)
159{
160 unsigned int i, bootmem_pages = 0, memend_pfn = 0;
161
162 for (i = 0; i < MAX_NUMNODES; i++) {
163 np[i].start = -1U;
164 np[i].end = 0;
165 np[i].bootmap_pages = 0;
166 }
167
168 for (i = 0; i < mi->nr_banks; i++) {
169 unsigned long start, end;
170 int node;
171
172 if (mi->bank[i].size == 0) {
173 /*
174 * Mark this bank with an invalid node number
175 */
176 mi->bank[i].node = -1;
177 continue;
178 }
179
180 node = mi->bank[i].node;
181
182 /*
183 * Make sure we haven't exceeded the maximum number of nodes
184 * that we have in this configuration. If we have, we're in
185 * trouble. (maybe we ought to limit, instead of bugging?)
186 */
187 if (node >= MAX_NUMNODES)
188 BUG();
189 node_set_online(node);
190
191 /*
192 * Get the start and end pfns for this bank
193 */
194 start = O_PFN_UP(mi->bank[i].start);
195 end = O_PFN_DOWN(mi->bank[i].start + mi->bank[i].size);
196
197 if (np[node].start > start)
198 np[node].start = start;
199
200 if (np[node].end < end)
201 np[node].end = end;
202
203 if (memend_pfn < end)
204 memend_pfn = end;
205 }
206
207 /*
208 * Calculate the number of pages we require to
209 * store the bootmem bitmaps.
210 */
211 for_each_online_node(i) {
212 if (np[i].end == 0)
213 continue;
214
215 np[i].bootmap_pages = bootmem_bootmap_pages(np[i].end -
216 np[i].start);
217 bootmem_pages += np[i].bootmap_pages;
218 }
219
220 high_memory = __va(memend_pfn << PAGE_SHIFT);
221
222 /*
223 * This doesn't seem to be used by the Linux memory
224 * manager any more. If we can get rid of it, we
225 * also get rid of some of the stuff above as well.
226 */
227 max_low_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
228 max_pfn = memend_pfn - O_PFN_DOWN(PHYS_OFFSET);
229
230 return bootmem_pages;
231}
232
233static int __init check_initrd(struct meminfo *mi)
234{
235 int initrd_node = -2;
236#ifdef CONFIG_BLK_DEV_INITRD
237 unsigned long end = phys_initrd_start + phys_initrd_size;
238
239 /*
240 * Make sure that the initrd is within a valid area of
241 * memory.
242 */
243 if (phys_initrd_size) {
244 unsigned int i;
245
246 initrd_node = -1;
247
248 for (i = 0; i < mi->nr_banks; i++) {
249 unsigned long bank_end;
250
251 bank_end = mi->bank[i].start + mi->bank[i].size;
252
253 if (mi->bank[i].start <= phys_initrd_start &&
254 end <= bank_end)
255 initrd_node = mi->bank[i].node;
256 }
257 }
258
259 if (initrd_node == -1) {
260 printk(KERN_ERR "initrd (0x%08lx - 0x%08lx) extends beyond "
261 "physical memory - disabling initrd\n",
262 phys_initrd_start, end);
263 phys_initrd_start = phys_initrd_size = 0;
264 }
265#endif
266
267 return initrd_node;
268}
269
270/*
271 * Reserve the various regions of node 0
272 */
273static __init void reserve_node_zero(unsigned int bootmap_pfn, unsigned int bootmap_pages)
274{
275 pg_data_t *pgdat = NODE_DATA(0);
276 unsigned long res_size = 0;
277
278 /*
279 * Register the kernel text and data with bootmem.
280 * Note that this can only be in node 0.
281 */
282#ifdef CONFIG_XIP_KERNEL
283 reserve_bootmem_node(pgdat, __pa(&__data_start), &_end - &__data_start);
284#else
285 reserve_bootmem_node(pgdat, __pa(&_stext), &_end - &_stext);
286#endif
287
288 /*
289 * Reserve the page tables. These are already in use,
290 * and can only be in node 0.
291 */
292 reserve_bootmem_node(pgdat, __pa(swapper_pg_dir),
293 PTRS_PER_PGD * sizeof(pgd_t));
294
295 /*
296 * And don't forget to reserve the allocator bitmap,
297 * which will be freed later.
298 */
299 reserve_bootmem_node(pgdat, bootmap_pfn << PAGE_SHIFT,
300 bootmap_pages << PAGE_SHIFT);
301
302 /*
303 * Hmm... This should go elsewhere, but we really really need to
304 * stop things allocating the low memory; ideally we need a better
305 * implementation of GFP_DMA which does not assume that DMA-able
306 * memory starts at zero.
307 */
308 if (machine_is_integrator() || machine_is_cintegrator())
309 res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
310
311 /*
312 * These should likewise go elsewhere. They pre-reserve the
313 * screen memory region at the start of main system memory.
314 */
315 if (machine_is_edb7211())
316 res_size = 0x00020000;
317 if (machine_is_p720t())
318 res_size = 0x00014000;
319
320#ifdef CONFIG_SA1111
321 /*
322 * Because of the SA1111 DMA bug, we want to preserve our
323 * precious DMA-able memory...
324 */
325 res_size = __pa(swapper_pg_dir) - PHYS_OFFSET;
326#endif
327 if (res_size)
328 reserve_bootmem_node(pgdat, PHYS_OFFSET, res_size);
329}
330
331/*
332 * Register all available RAM in this node with the bootmem allocator.
333 */
334static inline void free_bootmem_node_bank(int node, struct meminfo *mi)
335{
336 pg_data_t *pgdat = NODE_DATA(node);
337 int bank;
338
339 for (bank = 0; bank < mi->nr_banks; bank++)
340 if (mi->bank[bank].node == node)
341 free_bootmem_node(pgdat, mi->bank[bank].start,
342 mi->bank[bank].size);
343}
344
345/*
346 * Initialise the bootmem allocator for all nodes. This is called
347 * early during the architecture specific initialisation.
348 */
349static void __init bootmem_init(struct meminfo *mi)
350{
351 struct node_info node_info[MAX_NUMNODES], *np = node_info;
352 unsigned int bootmap_pages, bootmap_pfn, map_pg;
353 int node, initrd_node;
354
355 bootmap_pages = find_memend_and_nodes(mi, np);
356 bootmap_pfn = find_bootmap_pfn(0, mi, bootmap_pages);
357 initrd_node = check_initrd(mi);
358
359 map_pg = bootmap_pfn;
360
361 /*
362 * Initialise the bootmem nodes.
363 *
364 * What we really want to do is:
365 *
366 * unmap_all_regions_except_kernel();
367 * for_each_node_in_reverse_order(node) {
368 * map_node(node);
369 * allocate_bootmem_map(node);
370 * init_bootmem_node(node);
371 * free_bootmem_node(node);
372 * }
373 *
374 * but this is a 2.5-type change. For now, we just set
375 * the nodes up in reverse order.
376 *
377 * (we could also do with rolling bootmem_init and paging_init
378 * into one generic "memory_init" type function).
379 */
380 np += num_online_nodes() - 1;
381 for (node = num_online_nodes() - 1; node >= 0; node--, np--) {
382 /*
383 * If there are no pages in this node, ignore it.
384 * Note that node 0 must always have some pages.
385 */
386 if (np->end == 0 || !node_online(node)) {
387 if (node == 0)
388 BUG();
389 continue;
390 }
391
392 /*
393 * Initialise the bootmem allocator.
394 */
395 init_bootmem_node(NODE_DATA(node), map_pg, np->start, np->end);
396 free_bootmem_node_bank(node, mi);
397 map_pg += np->bootmap_pages;
398
399 /*
400 * If this is node 0, we need to reserve some areas ASAP -
401 * we may use bootmem on node 0 to setup the other nodes.
402 */
403 if (node == 0)
404 reserve_node_zero(bootmap_pfn, bootmap_pages);
405 }
406
407
408#ifdef CONFIG_BLK_DEV_INITRD
409 if (phys_initrd_size && initrd_node >= 0) {
410 reserve_bootmem_node(NODE_DATA(initrd_node), phys_initrd_start,
411 phys_initrd_size);
412 initrd_start = __phys_to_virt(phys_initrd_start);
413 initrd_end = initrd_start + phys_initrd_size;
414 }
415#endif
416
417 BUG_ON(map_pg != bootmap_pfn + bootmap_pages);
418}
419
420/*
421 * paging_init() sets up the page tables, initialises the zone memory
422 * maps, and sets up the zero page, bad page and bad page tables.
423 */
424void __init paging_init(struct meminfo *mi, struct machine_desc *mdesc)
425{
426 void *zero_page;
427 int node;
428
429 bootmem_init(mi);
430
431 memcpy(&meminfo, mi, sizeof(meminfo));
432
433 /*
434 * allocate the zero page. Note that we count on this going ok.
435 */
436 zero_page = alloc_bootmem_low_pages(PAGE_SIZE);
437
438 /*
439 * initialise the page tables.
440 */
441 memtable_init(mi);
442 if (mdesc->map_io)
443 mdesc->map_io();
444 flush_tlb_all();
445
446 /*
447 * initialise the zones within each node
448 */
449 for_each_online_node(node) {
450 unsigned long zone_size[MAX_NR_ZONES];
451 unsigned long zhole_size[MAX_NR_ZONES];
452 struct bootmem_data *bdata;
453 pg_data_t *pgdat;
454 int i;
455
456 /*
457 * Initialise the zone size information.
458 */
459 for (i = 0; i < MAX_NR_ZONES; i++) {
460 zone_size[i] = 0;
461 zhole_size[i] = 0;
462 }
463
464 pgdat = NODE_DATA(node);
465 bdata = pgdat->bdata;
466
467 /*
468 * The size of this node has already been determined.
469 * If we need to do anything fancy with the allocation
470 * of this memory to the zones, now is the time to do
471 * it.
472 */
473 zone_size[0] = bdata->node_low_pfn -
474 (bdata->node_boot_start >> PAGE_SHIFT);
475
476 /*
477 * If this zone has zero size, skip it.
478 */
479 if (!zone_size[0])
480 continue;
481
482 /*
483 * For each bank in this node, calculate the size of the
484 * holes. holes = node_size - sum(bank_sizes_in_node)
485 */
486 zhole_size[0] = zone_size[0];
487 for (i = 0; i < mi->nr_banks; i++) {
488 if (mi->bank[i].node != node)
489 continue;
490
491 zhole_size[0] -= mi->bank[i].size >> PAGE_SHIFT;
492 }
493
494 /*
495 * Adjust the sizes according to any special
496 * requirements for this machine type.
497 */
498 arch_adjust_zones(node, zone_size, zhole_size);
499
500 free_area_init_node(node, pgdat, zone_size,
501 bdata->node_boot_start >> PAGE_SHIFT, zhole_size);
502 }
503
504 /*
505 * finish off the bad pages once
506 * the mem_map is initialised
507 */
508 memzero(zero_page, PAGE_SIZE);
509 empty_zero_page = virt_to_page(zero_page);
510 flush_dcache_page(empty_zero_page);
511}
512
513static inline void free_area(unsigned long addr, unsigned long end, char *s)
514{
515 unsigned int size = (end - addr) >> 10;
516
517 for (; addr < end; addr += PAGE_SIZE) {
518 struct page *page = virt_to_page(addr);
519 ClearPageReserved(page);
520 set_page_count(page, 1);
521 free_page(addr);
522 totalram_pages++;
523 }
524
525 if (size && s)
526 printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
527}
528
529/*
530 * mem_init() marks the free areas in the mem_map and tells us how much
531 * memory is free. This is done after various parts of the system have
532 * claimed their memory after the kernel image.
533 */
534void __init mem_init(void)
535{
536 unsigned int codepages, datapages, initpages;
537 int i, node;
538
539 codepages = &_etext - &_text;
540 datapages = &_end - &__data_start;
541 initpages = &__init_end - &__init_begin;
542
543#ifndef CONFIG_DISCONTIGMEM
544 max_mapnr = virt_to_page(high_memory) - mem_map;
545#endif
546
547 /*
548 * We may have non-contiguous memory.
549 */
550 if (meminfo.nr_banks != 1)
551 create_memmap_holes(&meminfo);
552
553 /* this will put all unused low memory onto the freelists */
554 for_each_online_node(node) {
555 pg_data_t *pgdat = NODE_DATA(node);
556
557 if (pgdat->node_spanned_pages != 0)
558 totalram_pages += free_all_bootmem_node(pgdat);
559 }
560
561#ifdef CONFIG_SA1111
562 /* now that our DMA memory is actually so designated, we can free it */
563 free_area(PAGE_OFFSET, (unsigned long)swapper_pg_dir, NULL);
564#endif
565
566 /*
567 * Since our memory may not be contiguous, calculate the
568 * real number of pages we have in this system
569 */
570 printk(KERN_INFO "Memory:");
571
572 num_physpages = 0;
573 for (i = 0; i < meminfo.nr_banks; i++) {
574 num_physpages += meminfo.bank[i].size >> PAGE_SHIFT;
575 printk(" %ldMB", meminfo.bank[i].size >> 20);
576 }
577
578 printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
579 printk(KERN_NOTICE "Memory: %luKB available (%dK code, "
580 "%dK data, %dK init)\n",
581 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
582 codepages >> 10, datapages >> 10, initpages >> 10);
583
584 if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
585 extern int sysctl_overcommit_memory;
586 /*
587 * On a machine this small we won't get
588 * anywhere without overcommit, so turn
589 * it on by default.
590 */
591 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
592 }
593}
594
595void free_initmem(void)
596{
597 if (!machine_is_integrator() && !machine_is_cintegrator()) {
598 free_area((unsigned long)(&__init_begin),
599 (unsigned long)(&__init_end),
600 "init");
601 }
602}
603
604#ifdef CONFIG_BLK_DEV_INITRD
605
606static int keep_initrd;
607
608void free_initrd_mem(unsigned long start, unsigned long end)
609{
610 if (!keep_initrd)
611 free_area(start, end, "initrd");
612}
613
614static int __init keepinitrd_setup(char *__unused)
615{
616 keep_initrd = 1;
617 return 1;
618}
619
620__setup("keepinitrd", keepinitrd_setup);
621#endif