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v3.1
  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#include <linux/of_fdt.h>
 19#include <linux/highmem.h>
 20#include <linux/gfp.h>
 21#include <linux/memblock.h>
 22#include <linux/sort.h>
 
 
 23
 
 24#include <asm/mach-types.h>
 
 
 25#include <asm/prom.h>
 26#include <asm/sections.h>
 27#include <asm/setup.h>
 28#include <asm/sizes.h>
 29#include <asm/tlb.h>
 30#include <asm/fixmap.h>
 
 31
 32#include <asm/mach/arch.h>
 33#include <asm/mach/map.h>
 34
 35#include "mm.h"
 36
 37static unsigned long phys_initrd_start __initdata = 0;
 
 
 
 
 
 
 
 
 38static unsigned long phys_initrd_size __initdata = 0;
 39
 40static int __init early_initrd(char *p)
 41{
 42	unsigned long start, size;
 
 43	char *endp;
 44
 45	start = memparse(p, &endp);
 46	if (*endp == ',') {
 47		size = memparse(endp + 1, NULL);
 48
 49		phys_initrd_start = start;
 50		phys_initrd_size = size;
 51	}
 52	return 0;
 53}
 54early_param("initrd", early_initrd);
 55
 56static int __init parse_tag_initrd(const struct tag *tag)
 57{
 58	printk(KERN_WARNING "ATAG_INITRD is deprecated; "
 59		"please update your bootloader.\n");
 60	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
 61	phys_initrd_size = tag->u.initrd.size;
 62	return 0;
 63}
 64
 65__tagtable(ATAG_INITRD, parse_tag_initrd);
 66
 67static int __init parse_tag_initrd2(const struct tag *tag)
 68{
 69	phys_initrd_start = tag->u.initrd.start;
 70	phys_initrd_size = tag->u.initrd.size;
 71	return 0;
 72}
 73
 74__tagtable(ATAG_INITRD2, parse_tag_initrd2);
 75
 76#ifdef CONFIG_OF_FLATTREE
 77void __init early_init_dt_setup_initrd_arch(unsigned long start, unsigned long end)
 78{
 79	phys_initrd_start = start;
 80	phys_initrd_size = end - start;
 81}
 82#endif /* CONFIG_OF_FLATTREE */
 83
 84/*
 85 * This keeps memory configuration data used by a couple memory
 86 * initialization functions, as well as show_mem() for the skipping
 87 * of holes in the memory map.  It is populated by arm_add_memory().
 88 */
 89struct meminfo meminfo;
 90
 91void show_mem(unsigned int filter)
 92{
 93	int free = 0, total = 0, reserved = 0;
 94	int shared = 0, cached = 0, slab = 0, i;
 95	struct meminfo * mi = &meminfo;
 96
 97	printk("Mem-info:\n");
 98	show_free_areas(filter);
 99
100	for_each_bank (i, mi) {
101		struct membank *bank = &mi->bank[i];
102		unsigned int pfn1, pfn2;
103		struct page *page, *end;
104
105		pfn1 = bank_pfn_start(bank);
106		pfn2 = bank_pfn_end(bank);
107
108		page = pfn_to_page(pfn1);
109		end  = pfn_to_page(pfn2 - 1) + 1;
110
111		do {
112			total++;
113			if (PageReserved(page))
114				reserved++;
115			else if (PageSwapCache(page))
116				cached++;
117			else if (PageSlab(page))
118				slab++;
119			else if (!page_count(page))
120				free++;
121			else
122				shared += page_count(page) - 1;
123			page++;
124		} while (page < end);
125	}
126
127	printk("%d pages of RAM\n", total);
128	printk("%d free pages\n", free);
129	printk("%d reserved pages\n", reserved);
130	printk("%d slab pages\n", slab);
131	printk("%d pages shared\n", shared);
132	printk("%d pages swap cached\n", cached);
133}
134
135static void __init find_limits(unsigned long *min, unsigned long *max_low,
136	unsigned long *max_high)
137{
138	struct meminfo *mi = &meminfo;
139	int i;
140
141	*min = -1UL;
142	*max_low = *max_high = 0;
143
144	for_each_bank (i, mi) {
145		struct membank *bank = &mi->bank[i];
146		unsigned long start, end;
147
148		start = bank_pfn_start(bank);
149		end = bank_pfn_end(bank);
150
151		if (*min > start)
152			*min = start;
153		if (*max_high < end)
154			*max_high = end;
155		if (bank->highmem)
156			continue;
157		if (*max_low < end)
158			*max_low = end;
159	}
160}
161
162static void __init arm_bootmem_init(unsigned long start_pfn,
163	unsigned long end_pfn)
164{
165	struct memblock_region *reg;
166	unsigned int boot_pages;
167	phys_addr_t bitmap;
168	pg_data_t *pgdat;
169
170	/*
171	 * Allocate the bootmem bitmap page.  This must be in a region
172	 * of memory which has already been mapped.
173	 */
174	boot_pages = bootmem_bootmap_pages(end_pfn - start_pfn);
175	bitmap = memblock_alloc_base(boot_pages << PAGE_SHIFT, L1_CACHE_BYTES,
176				__pfn_to_phys(end_pfn));
177
178	/*
179	 * Initialise the bootmem allocator, handing the
180	 * memory banks over to bootmem.
181	 */
182	node_set_online(0);
183	pgdat = NODE_DATA(0);
184	init_bootmem_node(pgdat, __phys_to_pfn(bitmap), start_pfn, end_pfn);
185
186	/* Free the lowmem regions from memblock into bootmem. */
187	for_each_memblock(memory, reg) {
188		unsigned long start = memblock_region_memory_base_pfn(reg);
189		unsigned long end = memblock_region_memory_end_pfn(reg);
190
191		if (end >= end_pfn)
192			end = end_pfn;
193		if (start >= end)
194			break;
195
196		free_bootmem(__pfn_to_phys(start), (end - start) << PAGE_SHIFT);
197	}
198
199	/* Reserve the lowmem memblock reserved regions in bootmem. */
200	for_each_memblock(reserved, reg) {
201		unsigned long start = memblock_region_reserved_base_pfn(reg);
202		unsigned long end = memblock_region_reserved_end_pfn(reg);
203
204		if (end >= end_pfn)
205			end = end_pfn;
206		if (start >= end)
207			break;
208
209		reserve_bootmem(__pfn_to_phys(start),
210			        (end - start) << PAGE_SHIFT, BOOTMEM_DEFAULT);
211	}
212}
213
214#ifdef CONFIG_ZONE_DMA
215
216unsigned long arm_dma_zone_size __read_mostly;
217EXPORT_SYMBOL(arm_dma_zone_size);
218
219/*
220 * The DMA mask corresponding to the maximum bus address allocatable
221 * using GFP_DMA.  The default here places no restriction on DMA
222 * allocations.  This must be the smallest DMA mask in the system,
223 * so a successful GFP_DMA allocation will always satisfy this.
224 */
225u32 arm_dma_limit;
 
226
227static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
228	unsigned long dma_size)
229{
230	if (size[0] <= dma_size)
231		return;
232
233	size[ZONE_NORMAL] = size[0] - dma_size;
234	size[ZONE_DMA] = dma_size;
235	hole[ZONE_NORMAL] = hole[0];
236	hole[ZONE_DMA] = 0;
237}
238#endif
239
240static void __init arm_bootmem_free(unsigned long min, unsigned long max_low,
 
 
 
 
 
 
 
 
 
 
 
 
241	unsigned long max_high)
242{
243	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
244	struct memblock_region *reg;
245
246	/*
247	 * initialise the zones.
248	 */
249	memset(zone_size, 0, sizeof(zone_size));
250
251	/*
252	 * The memory size has already been determined.  If we need
253	 * to do anything fancy with the allocation of this memory
254	 * to the zones, now is the time to do it.
255	 */
256	zone_size[0] = max_low - min;
257#ifdef CONFIG_HIGHMEM
258	zone_size[ZONE_HIGHMEM] = max_high - max_low;
259#endif
260
261	/*
262	 * Calculate the size of the holes.
263	 *  holes = node_size - sum(bank_sizes)
264	 */
265	memcpy(zhole_size, zone_size, sizeof(zhole_size));
266	for_each_memblock(memory, reg) {
267		unsigned long start = memblock_region_memory_base_pfn(reg);
268		unsigned long end = memblock_region_memory_end_pfn(reg);
269
270		if (start < max_low) {
271			unsigned long low_end = min(end, max_low);
272			zhole_size[0] -= low_end - start;
273		}
274#ifdef CONFIG_HIGHMEM
275		if (end > max_low) {
276			unsigned long high_start = max(start, max_low);
277			zhole_size[ZONE_HIGHMEM] -= end - high_start;
278		}
279#endif
280	}
281
282#ifdef CONFIG_ZONE_DMA
283	/*
284	 * Adjust the sizes according to any special requirements for
285	 * this machine type.
286	 */
287	if (arm_dma_zone_size) {
288		arm_adjust_dma_zone(zone_size, zhole_size,
289			arm_dma_zone_size >> PAGE_SHIFT);
290		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
291	} else
292		arm_dma_limit = 0xffffffff;
293#endif
294
295	free_area_init_node(0, zone_size, min, zhole_size);
296}
297
298#ifdef CONFIG_HAVE_ARCH_PFN_VALID
299int pfn_valid(unsigned long pfn)
300{
301	return memblock_is_memory(__pfn_to_phys(pfn));
302}
303EXPORT_SYMBOL(pfn_valid);
304#endif
305
306#ifndef CONFIG_SPARSEMEM
307static void arm_memory_present(void)
308{
309}
310#else
311static void arm_memory_present(void)
312{
313	struct memblock_region *reg;
314
315	for_each_memblock(memory, reg)
316		memory_present(0, memblock_region_memory_base_pfn(reg),
317			       memblock_region_memory_end_pfn(reg));
318}
319#endif
320
321static int __init meminfo_cmp(const void *_a, const void *_b)
322{
323	const struct membank *a = _a, *b = _b;
324	long cmp = bank_pfn_start(a) - bank_pfn_start(b);
325	return cmp < 0 ? -1 : cmp > 0 ? 1 : 0;
326}
327
328void __init arm_memblock_init(struct meminfo *mi, struct machine_desc *mdesc)
329{
330	int i;
331
332	sort(&meminfo.bank, meminfo.nr_banks, sizeof(meminfo.bank[0]), meminfo_cmp, NULL);
333
334	memblock_init();
335	for (i = 0; i < mi->nr_banks; i++)
336		memblock_add(mi->bank[i].start, mi->bank[i].size);
337
338	/* Register the kernel text, kernel data and initrd with memblock. */
339#ifdef CONFIG_XIP_KERNEL
340	memblock_reserve(__pa(_sdata), _end - _sdata);
341#else
342	memblock_reserve(__pa(_stext), _end - _stext);
343#endif
344#ifdef CONFIG_BLK_DEV_INITRD
345	if (phys_initrd_size &&
346	    !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
347		pr_err("INITRD: 0x%08lx+0x%08lx is not a memory region - disabling initrd\n",
348		       phys_initrd_start, phys_initrd_size);
349		phys_initrd_start = phys_initrd_size = 0;
 
 
350	}
351	if (phys_initrd_size &&
352	    memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
353		pr_err("INITRD: 0x%08lx+0x%08lx overlaps in-use memory region - disabling initrd\n",
354		       phys_initrd_start, phys_initrd_size);
355		phys_initrd_start = phys_initrd_size = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
356	}
357	if (phys_initrd_size) {
358		memblock_reserve(phys_initrd_start, phys_initrd_size);
359
360		/* Now convert initrd to virtual addresses */
361		initrd_start = __phys_to_virt(phys_initrd_start);
362		initrd_end = initrd_start + phys_initrd_size;
 
363	}
 
 
 
 
 
 
364#endif
 
 
 
 
 
 
 
 
365
366	arm_mm_memblock_reserve();
367	arm_dt_memblock_reserve();
368
369	/* reserve any platform specific memblock areas */
370	if (mdesc->reserve)
371		mdesc->reserve();
372
373	memblock_analyze();
 
 
 
 
 
 
374	memblock_dump_all();
375}
376
377void __init bootmem_init(void)
378{
379	unsigned long min, max_low, max_high;
380
 
381	max_low = max_high = 0;
382
383	find_limits(&min, &max_low, &max_high);
384
385	arm_bootmem_init(min, max_low);
 
386
387	/*
388	 * Sparsemem tries to allocate bootmem in memory_present(),
389	 * so must be done after the fixed reservations
390	 */
391	arm_memory_present();
392
393	/*
394	 * sparse_init() needs the bootmem allocator up and running.
395	 */
396	sparse_init();
397
398	/*
399	 * Now free the memory - free_area_init_node needs
400	 * the sparse mem_map arrays initialized by sparse_init()
401	 * for memmap_init_zone(), otherwise all PFNs are invalid.
402	 */
403	arm_bootmem_free(min, max_low, max_high);
404
405	high_memory = __va(((phys_addr_t)max_low << PAGE_SHIFT) - 1) + 1;
406
407	/*
408	 * This doesn't seem to be used by the Linux memory manager any
409	 * more, but is used by ll_rw_block.  If we can get rid of it, we
410	 * also get rid of some of the stuff above as well.
411	 *
412	 * Note: max_low_pfn and max_pfn reflect the number of _pages_ in
413	 * the system, not the maximum PFN.
414	 */
415	max_low_pfn = max_low - PHYS_PFN_OFFSET;
416	max_pfn = max_high - PHYS_PFN_OFFSET;
417}
418
419static inline int free_area(unsigned long pfn, unsigned long end, char *s)
420{
421	unsigned int pages = 0, size = (end - pfn) << (PAGE_SHIFT - 10);
422
423	for (; pfn < end; pfn++) {
424		struct page *page = pfn_to_page(pfn);
425		ClearPageReserved(page);
426		init_page_count(page);
427		__free_page(page);
428		pages++;
429	}
430
431	if (size && s)
432		printk(KERN_INFO "Freeing %s memory: %dK\n", s, size);
433
434	return pages;
435}
436
437/*
438 * Poison init memory with an undefined instruction (ARM) or a branch to an
439 * undefined instruction (Thumb).
440 */
441static inline void poison_init_mem(void *s, size_t count)
442{
443	u32 *p = (u32 *)s;
444	for (; count != 0; count -= 4)
445		*p++ = 0xe7fddef0;
446}
447
448static inline void
449free_memmap(unsigned long start_pfn, unsigned long end_pfn)
450{
451	struct page *start_pg, *end_pg;
452	unsigned long pg, pgend;
453
454	/*
455	 * Convert start_pfn/end_pfn to a struct page pointer.
456	 */
457	start_pg = pfn_to_page(start_pfn - 1) + 1;
458	end_pg = pfn_to_page(end_pfn - 1) + 1;
459
460	/*
461	 * Convert to physical addresses, and
462	 * round start upwards and end downwards.
463	 */
464	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
465	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
466
467	/*
468	 * If there are free pages between these,
469	 * free the section of the memmap array.
470	 */
471	if (pg < pgend)
472		free_bootmem(pg, pgend - pg);
473}
474
475/*
476 * The mem_map array can get very big.  Free the unused area of the memory map.
477 */
478static void __init free_unused_memmap(struct meminfo *mi)
479{
480	unsigned long bank_start, prev_bank_end = 0;
481	unsigned int i;
482
483	/*
484	 * This relies on each bank being in address order.
485	 * The banks are sorted previously in bootmem_init().
486	 */
487	for_each_bank(i, mi) {
488		struct membank *bank = &mi->bank[i];
489
490		bank_start = bank_pfn_start(bank);
491
492#ifdef CONFIG_SPARSEMEM
493		/*
494		 * Take care not to free memmap entries that don't exist
495		 * due to SPARSEMEM sections which aren't present.
496		 */
497		bank_start = min(bank_start,
498				 ALIGN(prev_bank_end, PAGES_PER_SECTION));
499#else
500		/*
501		 * Align down here since the VM subsystem insists that the
502		 * memmap entries are valid from the bank start aligned to
503		 * MAX_ORDER_NR_PAGES.
504		 */
505		bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
506#endif
507		/*
508		 * If we had a previous bank, and there is a space
509		 * between the current bank and the previous, free it.
510		 */
511		if (prev_bank_end && prev_bank_end < bank_start)
512			free_memmap(prev_bank_end, bank_start);
513
514		/*
515		 * Align up here since the VM subsystem insists that the
516		 * memmap entries are valid from the bank end aligned to
517		 * MAX_ORDER_NR_PAGES.
518		 */
519		prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
 
520	}
521
522#ifdef CONFIG_SPARSEMEM
523	if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
524		free_memmap(prev_bank_end,
525			    ALIGN(prev_bank_end, PAGES_PER_SECTION));
526#endif
527}
528
 
 
 
 
 
 
 
 
529static void __init free_highpages(void)
530{
531#ifdef CONFIG_HIGHMEM
532	unsigned long max_low = max_low_pfn + PHYS_PFN_OFFSET;
533	struct memblock_region *mem, *res;
534
535	/* set highmem page free */
536	for_each_memblock(memory, mem) {
537		unsigned long start = memblock_region_memory_base_pfn(mem);
538		unsigned long end = memblock_region_memory_end_pfn(mem);
539
540		/* Ignore complete lowmem entries */
541		if (end <= max_low)
542			continue;
543
 
 
 
544		/* Truncate partial highmem entries */
545		if (start < max_low)
546			start = max_low;
547
548		/* Find and exclude any reserved regions */
549		for_each_memblock(reserved, res) {
550			unsigned long res_start, res_end;
551
552			res_start = memblock_region_reserved_base_pfn(res);
553			res_end = memblock_region_reserved_end_pfn(res);
554
555			if (res_end < start)
556				continue;
557			if (res_start < start)
558				res_start = start;
559			if (res_start > end)
560				res_start = end;
561			if (res_end > end)
562				res_end = end;
563			if (res_start != start)
564				totalhigh_pages += free_area(start, res_start,
565							     NULL);
566			start = res_end;
567			if (start == end)
568				break;
569		}
570
571		/* And now free anything which remains */
572		if (start < end)
573			totalhigh_pages += free_area(start, end, NULL);
574	}
575	totalram_pages += totalhigh_pages;
576#endif
577}
578
579/*
580 * mem_init() marks the free areas in the mem_map and tells us how much
581 * memory is free.  This is done after various parts of the system have
582 * claimed their memory after the kernel image.
583 */
584void __init mem_init(void)
585{
586	unsigned long reserved_pages, free_pages;
587	struct memblock_region *reg;
588	int i;
589#ifdef CONFIG_HAVE_TCM
590	/* These pointers are filled in on TCM detection */
591	extern u32 dtcm_end;
592	extern u32 itcm_end;
593#endif
594
595	max_mapnr   = pfn_to_page(max_pfn + PHYS_PFN_OFFSET) - mem_map;
596
597	/* this will put all unused low memory onto the freelists */
598	free_unused_memmap(&meminfo);
599
600	totalram_pages += free_all_bootmem();
601
602#ifdef CONFIG_SA1111
603	/* now that our DMA memory is actually so designated, we can free it */
604	totalram_pages += free_area(PHYS_PFN_OFFSET,
605				    __phys_to_pfn(__pa(swapper_pg_dir)), NULL);
606#endif
607
608	free_highpages();
609
610	reserved_pages = free_pages = 0;
611
612	for_each_bank(i, &meminfo) {
613		struct membank *bank = &meminfo.bank[i];
614		unsigned int pfn1, pfn2;
615		struct page *page, *end;
616
617		pfn1 = bank_pfn_start(bank);
618		pfn2 = bank_pfn_end(bank);
619
620		page = pfn_to_page(pfn1);
621		end  = pfn_to_page(pfn2 - 1) + 1;
622
623		do {
624			if (PageReserved(page))
625				reserved_pages++;
626			else if (!page_count(page))
627				free_pages++;
628			page++;
629		} while (page < end);
630	}
631
632	/*
633	 * Since our memory may not be contiguous, calculate the
634	 * real number of pages we have in this system
635	 */
636	printk(KERN_INFO "Memory:");
637	num_physpages = 0;
638	for_each_memblock(memory, reg) {
639		unsigned long pages = memblock_region_memory_end_pfn(reg) -
640			memblock_region_memory_base_pfn(reg);
641		num_physpages += pages;
642		printk(" %ldMB", pages >> (20 - PAGE_SHIFT));
643	}
644	printk(" = %luMB total\n", num_physpages >> (20 - PAGE_SHIFT));
645
646	printk(KERN_NOTICE "Memory: %luk/%luk available, %luk reserved, %luK highmem\n",
647		nr_free_pages() << (PAGE_SHIFT-10),
648		free_pages << (PAGE_SHIFT-10),
649		reserved_pages << (PAGE_SHIFT-10),
650		totalhigh_pages << (PAGE_SHIFT-10));
651
652#define MLK(b, t) b, t, ((t) - (b)) >> 10
653#define MLM(b, t) b, t, ((t) - (b)) >> 20
654#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
655
656	printk(KERN_NOTICE "Virtual kernel memory layout:\n"
657			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
658#ifdef CONFIG_HAVE_TCM
659			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
660			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
661#endif
662			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
663#ifdef CONFIG_MMU
664			"    DMA     : 0x%08lx - 0x%08lx   (%4ld MB)\n"
665#endif
666			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
667			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
668#ifdef CONFIG_HIGHMEM
669			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
670#endif
 
671			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
672			"      .text : 0x%p" " - 0x%p" "   (%4d kB)\n"
673			"      .init : 0x%p" " - 0x%p" "   (%4d kB)\n"
674			"      .data : 0x%p" " - 0x%p" "   (%4d kB)\n"
675			"       .bss : 0x%p" " - 0x%p" "   (%4d kB)\n",
 
676
677			MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
678				(PAGE_SIZE)),
679#ifdef CONFIG_HAVE_TCM
680			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
681			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
682#endif
683			MLK(FIXADDR_START, FIXADDR_TOP),
684#ifdef CONFIG_MMU
685			MLM(CONSISTENT_BASE, CONSISTENT_END),
686#endif
687			MLM(VMALLOC_START, VMALLOC_END),
688			MLM(PAGE_OFFSET, (unsigned long)high_memory),
689#ifdef CONFIG_HIGHMEM
690			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
691				(PAGE_SIZE)),
692#endif
 
693			MLM(MODULES_VADDR, MODULES_END),
 
694
695			MLK_ROUNDUP(_text, _etext),
696			MLK_ROUNDUP(__init_begin, __init_end),
697			MLK_ROUNDUP(_sdata, _edata),
698			MLK_ROUNDUP(__bss_start, __bss_stop));
699
700#undef MLK
701#undef MLM
702#undef MLK_ROUNDUP
703
704	/*
705	 * Check boundaries twice: Some fundamental inconsistencies can
706	 * be detected at build time already.
707	 */
708#ifdef CONFIG_MMU
709	BUILD_BUG_ON(VMALLOC_END			> CONSISTENT_BASE);
710	BUG_ON(VMALLOC_END				> CONSISTENT_BASE);
711
712	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
713	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
714#endif
715
716#ifdef CONFIG_HIGHMEM
717	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
718	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
719#endif
 
720
721	if (PAGE_SIZE >= 16384 && num_physpages <= 128) {
722		extern int sysctl_overcommit_memory;
723		/*
724		 * On a machine this small we won't get
725		 * anywhere without overcommit, so turn
726		 * it on by default.
727		 */
728		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
729	}
 
730}
731
732void free_initmem(void)
 
 
 
 
 
733{
734#ifdef CONFIG_HAVE_TCM
735	extern char __tcm_start, __tcm_end;
736
737	poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
738	totalram_pages += free_area(__phys_to_pfn(__pa(&__tcm_start)),
739				    __phys_to_pfn(__pa(&__tcm_end)),
740				    "TCM link");
741#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
742
743	poison_init_mem(__init_begin, __init_end - __init_begin);
744	if (!machine_is_integrator() && !machine_is_cintegrator())
745		totalram_pages += free_area(__phys_to_pfn(__pa(__init_begin)),
746					    __phys_to_pfn(__pa(__init_end)),
747					    "init");
748}
749
750#ifdef CONFIG_BLK_DEV_INITRD
751
752static int keep_initrd;
753
754void free_initrd_mem(unsigned long start, unsigned long end)
755{
756	if (!keep_initrd) {
 
 
 
 
 
757		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
758		totalram_pages += free_area(__phys_to_pfn(__pa(start)),
759					    __phys_to_pfn(__pa(end)),
760					    "initrd");
761	}
762}
763
764static int __init keepinitrd_setup(char *__unused)
765{
766	keep_initrd = 1;
767	return 1;
768}
769
770__setup("keepinitrd", keepinitrd_setup);
771#endif
v4.17
  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/sched/signal.h>
 17#include <linux/sched/task.h>
 18#include <linux/export.h>
 19#include <linux/nodemask.h>
 20#include <linux/initrd.h>
 21#include <linux/of_fdt.h>
 22#include <linux/highmem.h>
 23#include <linux/gfp.h>
 24#include <linux/memblock.h>
 25#include <linux/dma-contiguous.h>
 26#include <linux/sizes.h>
 27#include <linux/stop_machine.h>
 28
 29#include <asm/cp15.h>
 30#include <asm/mach-types.h>
 31#include <asm/memblock.h>
 32#include <asm/memory.h>
 33#include <asm/prom.h>
 34#include <asm/sections.h>
 35#include <asm/setup.h>
 36#include <asm/system_info.h>
 37#include <asm/tlb.h>
 38#include <asm/fixmap.h>
 39#include <asm/ptdump.h>
 40
 41#include <asm/mach/arch.h>
 42#include <asm/mach/map.h>
 43
 44#include "mm.h"
 45
 46#ifdef CONFIG_CPU_CP15_MMU
 47unsigned long __init __clear_cr(unsigned long mask)
 48{
 49	cr_alignment = cr_alignment & ~mask;
 50	return cr_alignment;
 51}
 52#endif
 53
 54static phys_addr_t phys_initrd_start __initdata = 0;
 55static unsigned long phys_initrd_size __initdata = 0;
 56
 57static int __init early_initrd(char *p)
 58{
 59	phys_addr_t start;
 60	unsigned long size;
 61	char *endp;
 62
 63	start = memparse(p, &endp);
 64	if (*endp == ',') {
 65		size = memparse(endp + 1, NULL);
 66
 67		phys_initrd_start = start;
 68		phys_initrd_size = size;
 69	}
 70	return 0;
 71}
 72early_param("initrd", early_initrd);
 73
 74static int __init parse_tag_initrd(const struct tag *tag)
 75{
 76	pr_warn("ATAG_INITRD is deprecated; "
 77		"please update your bootloader.\n");
 78	phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
 79	phys_initrd_size = tag->u.initrd.size;
 80	return 0;
 81}
 82
 83__tagtable(ATAG_INITRD, parse_tag_initrd);
 84
 85static int __init parse_tag_initrd2(const struct tag *tag)
 86{
 87	phys_initrd_start = tag->u.initrd.start;
 88	phys_initrd_size = tag->u.initrd.size;
 89	return 0;
 90}
 91
 92__tagtable(ATAG_INITRD2, parse_tag_initrd2);
 93
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 94static void __init find_limits(unsigned long *min, unsigned long *max_low,
 95			       unsigned long *max_high)
 96{
 97	*max_low = PFN_DOWN(memblock_get_current_limit());
 98	*min = PFN_UP(memblock_start_of_DRAM());
 99	*max_high = PFN_DOWN(memblock_end_of_DRAM());
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
100}
101
102#ifdef CONFIG_ZONE_DMA
103
104phys_addr_t arm_dma_zone_size __read_mostly;
105EXPORT_SYMBOL(arm_dma_zone_size);
106
107/*
108 * The DMA mask corresponding to the maximum bus address allocatable
109 * using GFP_DMA.  The default here places no restriction on DMA
110 * allocations.  This must be the smallest DMA mask in the system,
111 * so a successful GFP_DMA allocation will always satisfy this.
112 */
113phys_addr_t arm_dma_limit;
114unsigned long arm_dma_pfn_limit;
115
116static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
117	unsigned long dma_size)
118{
119	if (size[0] <= dma_size)
120		return;
121
122	size[ZONE_NORMAL] = size[0] - dma_size;
123	size[ZONE_DMA] = dma_size;
124	hole[ZONE_NORMAL] = hole[0];
125	hole[ZONE_DMA] = 0;
126}
127#endif
128
129void __init setup_dma_zone(const struct machine_desc *mdesc)
130{
131#ifdef CONFIG_ZONE_DMA
132	if (mdesc->dma_zone_size) {
133		arm_dma_zone_size = mdesc->dma_zone_size;
134		arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
135	} else
136		arm_dma_limit = 0xffffffff;
137	arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
138#endif
139}
140
141static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
142	unsigned long max_high)
143{
144	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
145	struct memblock_region *reg;
146
147	/*
148	 * initialise the zones.
149	 */
150	memset(zone_size, 0, sizeof(zone_size));
151
152	/*
153	 * The memory size has already been determined.  If we need
154	 * to do anything fancy with the allocation of this memory
155	 * to the zones, now is the time to do it.
156	 */
157	zone_size[0] = max_low - min;
158#ifdef CONFIG_HIGHMEM
159	zone_size[ZONE_HIGHMEM] = max_high - max_low;
160#endif
161
162	/*
163	 * Calculate the size of the holes.
164	 *  holes = node_size - sum(bank_sizes)
165	 */
166	memcpy(zhole_size, zone_size, sizeof(zhole_size));
167	for_each_memblock(memory, reg) {
168		unsigned long start = memblock_region_memory_base_pfn(reg);
169		unsigned long end = memblock_region_memory_end_pfn(reg);
170
171		if (start < max_low) {
172			unsigned long low_end = min(end, max_low);
173			zhole_size[0] -= low_end - start;
174		}
175#ifdef CONFIG_HIGHMEM
176		if (end > max_low) {
177			unsigned long high_start = max(start, max_low);
178			zhole_size[ZONE_HIGHMEM] -= end - high_start;
179		}
180#endif
181	}
182
183#ifdef CONFIG_ZONE_DMA
184	/*
185	 * Adjust the sizes according to any special requirements for
186	 * this machine type.
187	 */
188	if (arm_dma_zone_size)
189		arm_adjust_dma_zone(zone_size, zhole_size,
190			arm_dma_zone_size >> PAGE_SHIFT);
 
 
 
191#endif
192
193	free_area_init_node(0, zone_size, min, zhole_size);
194}
195
196#ifdef CONFIG_HAVE_ARCH_PFN_VALID
197int pfn_valid(unsigned long pfn)
198{
199	return memblock_is_map_memory(__pfn_to_phys(pfn));
200}
201EXPORT_SYMBOL(pfn_valid);
202#endif
203
204#ifndef CONFIG_SPARSEMEM
205static void __init arm_memory_present(void)
206{
207}
208#else
209static void __init arm_memory_present(void)
210{
211	struct memblock_region *reg;
212
213	for_each_memblock(memory, reg)
214		memory_present(0, memblock_region_memory_base_pfn(reg),
215			       memblock_region_memory_end_pfn(reg));
216}
217#endif
218
219static bool arm_memblock_steal_permitted = true;
 
 
 
 
 
220
221phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
222{
223	phys_addr_t phys;
224
225	BUG_ON(!arm_memblock_steal_permitted);
226
227	phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
228	memblock_free(phys, size);
229	memblock_remove(phys, size);
230
231	return phys;
232}
233
234static void __init arm_initrd_init(void)
235{
 
236#ifdef CONFIG_BLK_DEV_INITRD
237	phys_addr_t start;
238	unsigned long size;
239
240	/* FDT scan will populate initrd_start */
241	if (initrd_start && !phys_initrd_size) {
242		phys_initrd_start = __virt_to_phys(initrd_start);
243		phys_initrd_size = initrd_end - initrd_start;
244	}
245
246	initrd_start = initrd_end = 0;
247
248	if (!phys_initrd_size)
249		return;
250
251	/*
252	 * Round the memory region to page boundaries as per free_initrd_mem()
253	 * This allows us to detect whether the pages overlapping the initrd
254	 * are in use, but more importantly, reserves the entire set of pages
255	 * as we don't want these pages allocated for other purposes.
256	 */
257	start = round_down(phys_initrd_start, PAGE_SIZE);
258	size = phys_initrd_size + (phys_initrd_start - start);
259	size = round_up(size, PAGE_SIZE);
260
261	if (!memblock_is_region_memory(start, size)) {
262		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
263		       (u64)start, size);
264		return;
265	}
 
 
266
267	if (memblock_is_region_reserved(start, size)) {
268		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
269		       (u64)start, size);
270		return;
271	}
272
273	memblock_reserve(start, size);
274
275	/* Now convert initrd to virtual addresses */
276	initrd_start = __phys_to_virt(phys_initrd_start);
277	initrd_end = initrd_start + phys_initrd_size;
278#endif
279}
280
281void __init arm_memblock_init(const struct machine_desc *mdesc)
282{
283	/* Register the kernel text, kernel data and initrd with memblock. */
284	memblock_reserve(__pa(KERNEL_START), KERNEL_END - KERNEL_START);
285
286	arm_initrd_init();
287
288	arm_mm_memblock_reserve();
 
289
290	/* reserve any platform specific memblock areas */
291	if (mdesc->reserve)
292		mdesc->reserve();
293
294	early_init_fdt_reserve_self();
295	early_init_fdt_scan_reserved_mem();
296
297	/* reserve memory for DMA contiguous allocations */
298	dma_contiguous_reserve(arm_dma_limit);
299
300	arm_memblock_steal_permitted = false;
301	memblock_dump_all();
302}
303
304void __init bootmem_init(void)
305{
306	unsigned long min, max_low, max_high;
307
308	memblock_allow_resize();
309	max_low = max_high = 0;
310
311	find_limits(&min, &max_low, &max_high);
312
313	early_memtest((phys_addr_t)min << PAGE_SHIFT,
314		      (phys_addr_t)max_low << PAGE_SHIFT);
315
316	/*
317	 * Sparsemem tries to allocate bootmem in memory_present(),
318	 * so must be done after the fixed reservations
319	 */
320	arm_memory_present();
321
322	/*
323	 * sparse_init() needs the bootmem allocator up and running.
324	 */
325	sparse_init();
326
327	/*
328	 * Now free the memory - free_area_init_node needs
329	 * the sparse mem_map arrays initialized by sparse_init()
330	 * for memmap_init_zone(), otherwise all PFNs are invalid.
331	 */
332	zone_sizes_init(min, max_low, max_high);
 
 
333
334	/*
335	 * This doesn't seem to be used by the Linux memory manager any
336	 * more, but is used by ll_rw_block.  If we can get rid of it, we
337	 * also get rid of some of the stuff above as well.
 
 
 
338	 */
339	min_low_pfn = min;
340	max_low_pfn = max_low;
341	max_pfn = max_high;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
342}
343
344/*
345 * Poison init memory with an undefined instruction (ARM) or a branch to an
346 * undefined instruction (Thumb).
347 */
348static inline void poison_init_mem(void *s, size_t count)
349{
350	u32 *p = (u32 *)s;
351	for (; count != 0; count -= 4)
352		*p++ = 0xe7fddef0;
353}
354
355static inline void
356free_memmap(unsigned long start_pfn, unsigned long end_pfn)
357{
358	struct page *start_pg, *end_pg;
359	phys_addr_t pg, pgend;
360
361	/*
362	 * Convert start_pfn/end_pfn to a struct page pointer.
363	 */
364	start_pg = pfn_to_page(start_pfn - 1) + 1;
365	end_pg = pfn_to_page(end_pfn - 1) + 1;
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		memblock_free_early(pg, pgend - pg);
380}
381
382/*
383 * The mem_map array can get very big.  Free the unused area of the memory map.
384 */
385static void __init free_unused_memmap(void)
386{
387	unsigned long start, prev_end = 0;
388	struct memblock_region *reg;
389
390	/*
391	 * This relies on each bank being in address order.
392	 * The banks are sorted previously in bootmem_init().
393	 */
394	for_each_memblock(memory, reg) {
395		start = memblock_region_memory_base_pfn(reg);
 
 
396
397#ifdef CONFIG_SPARSEMEM
398		/*
399		 * Take care not to free memmap entries that don't exist
400		 * due to SPARSEMEM sections which aren't present.
401		 */
402		start = min(start,
403				 ALIGN(prev_end, PAGES_PER_SECTION));
404#else
405		/*
406		 * Align down here since the VM subsystem insists that the
407		 * memmap entries are valid from the bank start aligned to
408		 * MAX_ORDER_NR_PAGES.
409		 */
410		start = round_down(start, MAX_ORDER_NR_PAGES);
411#endif
412		/*
413		 * If we had a previous bank, and there is a space
414		 * between the current bank and the previous, free it.
415		 */
416		if (prev_end && prev_end < start)
417			free_memmap(prev_end, start);
418
419		/*
420		 * Align up here since the VM subsystem insists that the
421		 * memmap entries are valid from the bank end aligned to
422		 * MAX_ORDER_NR_PAGES.
423		 */
424		prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
425				 MAX_ORDER_NR_PAGES);
426	}
427
428#ifdef CONFIG_SPARSEMEM
429	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
430		free_memmap(prev_end,
431			    ALIGN(prev_end, PAGES_PER_SECTION));
432#endif
433}
434
435#ifdef CONFIG_HIGHMEM
436static inline void free_area_high(unsigned long pfn, unsigned long end)
437{
438	for (; pfn < end; pfn++)
439		free_highmem_page(pfn_to_page(pfn));
440}
441#endif
442
443static void __init free_highpages(void)
444{
445#ifdef CONFIG_HIGHMEM
446	unsigned long max_low = max_low_pfn;
447	struct memblock_region *mem, *res;
448
449	/* set highmem page free */
450	for_each_memblock(memory, mem) {
451		unsigned long start = memblock_region_memory_base_pfn(mem);
452		unsigned long end = memblock_region_memory_end_pfn(mem);
453
454		/* Ignore complete lowmem entries */
455		if (end <= max_low)
456			continue;
457
458		if (memblock_is_nomap(mem))
459			continue;
460
461		/* Truncate partial highmem entries */
462		if (start < max_low)
463			start = max_low;
464
465		/* Find and exclude any reserved regions */
466		for_each_memblock(reserved, res) {
467			unsigned long res_start, res_end;
468
469			res_start = memblock_region_reserved_base_pfn(res);
470			res_end = memblock_region_reserved_end_pfn(res);
471
472			if (res_end < start)
473				continue;
474			if (res_start < start)
475				res_start = start;
476			if (res_start > end)
477				res_start = end;
478			if (res_end > end)
479				res_end = end;
480			if (res_start != start)
481				free_area_high(start, res_start);
 
482			start = res_end;
483			if (start == end)
484				break;
485		}
486
487		/* And now free anything which remains */
488		if (start < end)
489			free_area_high(start, end);
490	}
 
491#endif
492}
493
494/*
495 * mem_init() marks the free areas in the mem_map and tells us how much
496 * memory is free.  This is done after various parts of the system have
497 * claimed their memory after the kernel image.
498 */
499void __init mem_init(void)
500{
 
 
 
501#ifdef CONFIG_HAVE_TCM
502	/* These pointers are filled in on TCM detection */
503	extern u32 dtcm_end;
504	extern u32 itcm_end;
505#endif
506
507	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
508
509	/* this will put all unused low memory onto the freelists */
510	free_unused_memmap();
511	free_all_bootmem();
 
512
513#ifdef CONFIG_SA1111
514	/* now that our DMA memory is actually so designated, we can free it */
515	free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
 
516#endif
517
518	free_highpages();
519
520	mem_init_print_info(NULL);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
521
522#define MLK(b, t) b, t, ((t) - (b)) >> 10
523#define MLM(b, t) b, t, ((t) - (b)) >> 20
524#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
525
526	pr_notice("Virtual kernel memory layout:\n"
527			"    vector  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
528#ifdef CONFIG_HAVE_TCM
529			"    DTCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
530			"    ITCM    : 0x%08lx - 0x%08lx   (%4ld kB)\n"
531#endif
532			"    fixmap  : 0x%08lx - 0x%08lx   (%4ld kB)\n"
 
 
 
533			"    vmalloc : 0x%08lx - 0x%08lx   (%4ld MB)\n"
534			"    lowmem  : 0x%08lx - 0x%08lx   (%4ld MB)\n"
535#ifdef CONFIG_HIGHMEM
536			"    pkmap   : 0x%08lx - 0x%08lx   (%4ld MB)\n"
537#endif
538#ifdef CONFIG_MODULES
539			"    modules : 0x%08lx - 0x%08lx   (%4ld MB)\n"
540#endif
541			"      .text : 0x%p" " - 0x%p" "   (%4td kB)\n"
542			"      .init : 0x%p" " - 0x%p" "   (%4td kB)\n"
543			"      .data : 0x%p" " - 0x%p" "   (%4td kB)\n"
544			"       .bss : 0x%p" " - 0x%p" "   (%4td kB)\n",
545
546			MLK(VECTORS_BASE, VECTORS_BASE + PAGE_SIZE),
 
547#ifdef CONFIG_HAVE_TCM
548			MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
549			MLK(ITCM_OFFSET, (unsigned long) itcm_end),
550#endif
551			MLK(FIXADDR_START, FIXADDR_END),
 
 
 
552			MLM(VMALLOC_START, VMALLOC_END),
553			MLM(PAGE_OFFSET, (unsigned long)high_memory),
554#ifdef CONFIG_HIGHMEM
555			MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
556				(PAGE_SIZE)),
557#endif
558#ifdef CONFIG_MODULES
559			MLM(MODULES_VADDR, MODULES_END),
560#endif
561
562			MLK_ROUNDUP(_text, _etext),
563			MLK_ROUNDUP(__init_begin, __init_end),
564			MLK_ROUNDUP(_sdata, _edata),
565			MLK_ROUNDUP(__bss_start, __bss_stop));
566
567#undef MLK
568#undef MLM
569#undef MLK_ROUNDUP
570
571	/*
572	 * Check boundaries twice: Some fundamental inconsistencies can
573	 * be detected at build time already.
574	 */
575#ifdef CONFIG_MMU
 
 
 
576	BUILD_BUG_ON(TASK_SIZE				> MODULES_VADDR);
577	BUG_ON(TASK_SIZE 				> MODULES_VADDR);
578#endif
579
580#ifdef CONFIG_HIGHMEM
581	BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
582	BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE	> PAGE_OFFSET);
583#endif
584}
585
586#ifdef CONFIG_STRICT_KERNEL_RWX
587struct section_perm {
588	const char *name;
589	unsigned long start;
590	unsigned long end;
591	pmdval_t mask;
592	pmdval_t prot;
593	pmdval_t clear;
594};
595
596/* First section-aligned location at or after __start_rodata. */
597extern char __start_rodata_section_aligned[];
598
599static struct section_perm nx_perms[] = {
600	/* Make pages tables, etc before _stext RW (set NX). */
601	{
602		.name	= "pre-text NX",
603		.start	= PAGE_OFFSET,
604		.end	= (unsigned long)_stext,
605		.mask	= ~PMD_SECT_XN,
606		.prot	= PMD_SECT_XN,
607	},
608	/* Make init RW (set NX). */
609	{
610		.name	= "init NX",
611		.start	= (unsigned long)__init_begin,
612		.end	= (unsigned long)_sdata,
613		.mask	= ~PMD_SECT_XN,
614		.prot	= PMD_SECT_XN,
615	},
616	/* Make rodata NX (set RO in ro_perms below). */
617	{
618		.name	= "rodata NX",
619		.start  = (unsigned long)__start_rodata_section_aligned,
620		.end    = (unsigned long)__init_begin,
621		.mask   = ~PMD_SECT_XN,
622		.prot   = PMD_SECT_XN,
623	},
624};
625
626static struct section_perm ro_perms[] = {
627	/* Make kernel code and rodata RX (set RO). */
628	{
629		.name	= "text/rodata RO",
630		.start  = (unsigned long)_stext,
631		.end    = (unsigned long)__init_begin,
632#ifdef CONFIG_ARM_LPAE
633		.mask   = ~(L_PMD_SECT_RDONLY | PMD_SECT_AP2),
634		.prot   = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
635#else
636		.mask   = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
637		.prot   = PMD_SECT_APX | PMD_SECT_AP_WRITE,
638		.clear  = PMD_SECT_AP_WRITE,
639#endif
640	},
641};
642
643/*
644 * Updates section permissions only for the current mm (sections are
645 * copied into each mm). During startup, this is the init_mm. Is only
646 * safe to be called with preemption disabled, as under stop_machine().
647 */
648static inline void section_update(unsigned long addr, pmdval_t mask,
649				  pmdval_t prot, struct mm_struct *mm)
650{
651	pmd_t *pmd;
652
653	pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
654
655#ifdef CONFIG_ARM_LPAE
656	pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
657#else
658	if (addr & SECTION_SIZE)
659		pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
660	else
661		pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
662#endif
663	flush_pmd_entry(pmd);
664	local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
665}
666
667/* Make sure extended page tables are in use. */
668static inline bool arch_has_strict_perms(void)
669{
670	if (cpu_architecture() < CPU_ARCH_ARMv6)
671		return false;
672
673	return !!(get_cr() & CR_XP);
674}
675
676void set_section_perms(struct section_perm *perms, int n, bool set,
677			struct mm_struct *mm)
678{
679	size_t i;
680	unsigned long addr;
681
682	if (!arch_has_strict_perms())
683		return;
684
685	for (i = 0; i < n; i++) {
686		if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
687		    !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
688			pr_err("BUG: %s section %lx-%lx not aligned to %lx\n",
689				perms[i].name, perms[i].start, perms[i].end,
690				SECTION_SIZE);
691			continue;
692		}
693
694		for (addr = perms[i].start;
695		     addr < perms[i].end;
696		     addr += SECTION_SIZE)
697			section_update(addr, perms[i].mask,
698				set ? perms[i].prot : perms[i].clear, mm);
699	}
700
701}
702
703/**
704 * update_sections_early intended to be called only through stop_machine
705 * framework and executed by only one CPU while all other CPUs will spin and
706 * wait, so no locking is required in this function.
707 */
708static void update_sections_early(struct section_perm perms[], int n)
709{
710	struct task_struct *t, *s;
 
711
712	for_each_process(t) {
713		if (t->flags & PF_KTHREAD)
714			continue;
715		for_each_thread(t, s)
716			set_section_perms(perms, n, true, s->mm);
717	}
718	set_section_perms(perms, n, true, current->active_mm);
719	set_section_perms(perms, n, true, &init_mm);
720}
721
722static int __fix_kernmem_perms(void *unused)
723{
724	update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
725	return 0;
726}
727
728static void fix_kernmem_perms(void)
729{
730	stop_machine(__fix_kernmem_perms, NULL, NULL);
731}
732
733static int __mark_rodata_ro(void *unused)
734{
735	update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
736	return 0;
737}
738
739void mark_rodata_ro(void)
740{
741	stop_machine(__mark_rodata_ro, NULL, NULL);
742	debug_checkwx();
743}
744
745void set_kernel_text_rw(void)
746{
747	set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
748				current->active_mm);
749}
750
751void set_kernel_text_ro(void)
752{
753	set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
754				current->active_mm);
755}
756
757#else
758static inline void fix_kernmem_perms(void) { }
759#endif /* CONFIG_STRICT_KERNEL_RWX */
760
761void free_initmem(void)
762{
763	fix_kernmem_perms();
764
765	poison_init_mem(__init_begin, __init_end - __init_begin);
766	if (!machine_is_integrator() && !machine_is_cintegrator())
767		free_initmem_default(-1);
 
 
768}
769
770#ifdef CONFIG_BLK_DEV_INITRD
771
772static int keep_initrd;
773
774void free_initrd_mem(unsigned long start, unsigned long end)
775{
776	if (!keep_initrd) {
777		if (start == initrd_start)
778			start = round_down(start, PAGE_SIZE);
779		if (end == initrd_end)
780			end = round_up(end, PAGE_SIZE);
781
782		poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
783		free_reserved_area((void *)start, (void *)end, -1, "initrd");
 
 
784	}
785}
786
787static int __init keepinitrd_setup(char *__unused)
788{
789	keep_initrd = 1;
790	return 1;
791}
792
793__setup("keepinitrd", keepinitrd_setup);
794#endif