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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
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/export.h>
17#include <linux/nodemask.h>
18#include <linux/initrd.h>
19#include <linux/of_fdt.h>
20#include <linux/highmem.h>
21#include <linux/gfp.h>
22#include <linux/memblock.h>
23#include <linux/dma-contiguous.h>
24#include <linux/sizes.h>
25
26#include <asm/mach-types.h>
27#include <asm/memblock.h>
28#include <asm/prom.h>
29#include <asm/sections.h>
30#include <asm/setup.h>
31#include <asm/tlb.h>
32#include <asm/fixmap.h>
33
34#include <asm/mach/arch.h>
35#include <asm/mach/map.h>
36
37#include "mm.h"
38
39static phys_addr_t phys_initrd_start __initdata = 0;
40static unsigned long phys_initrd_size __initdata = 0;
41
42static int __init early_initrd(char *p)
43{
44 phys_addr_t start;
45 unsigned long size;
46 char *endp;
47
48 start = memparse(p, &endp);
49 if (*endp == ',') {
50 size = memparse(endp + 1, NULL);
51
52 phys_initrd_start = start;
53 phys_initrd_size = size;
54 }
55 return 0;
56}
57early_param("initrd", early_initrd);
58
59static int __init parse_tag_initrd(const struct tag *tag)
60{
61 printk(KERN_WARNING "ATAG_INITRD is deprecated; "
62 "please update your bootloader.\n");
63 phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
64 phys_initrd_size = tag->u.initrd.size;
65 return 0;
66}
67
68__tagtable(ATAG_INITRD, parse_tag_initrd);
69
70static int __init parse_tag_initrd2(const struct tag *tag)
71{
72 phys_initrd_start = tag->u.initrd.start;
73 phys_initrd_size = tag->u.initrd.size;
74 return 0;
75}
76
77__tagtable(ATAG_INITRD2, parse_tag_initrd2);
78
79/*
80 * This keeps memory configuration data used by a couple memory
81 * initialization functions, as well as show_mem() for the skipping
82 * of holes in the memory map. It is populated by arm_add_memory().
83 */
84struct meminfo meminfo;
85
86void show_mem(unsigned int filter)
87{
88 int free = 0, total = 0, reserved = 0;
89 int shared = 0, cached = 0, slab = 0, i;
90 struct meminfo * mi = &meminfo;
91
92 printk("Mem-info:\n");
93 show_free_areas(filter);
94
95 for_each_bank (i, mi) {
96 struct membank *bank = &mi->bank[i];
97 unsigned int pfn1, pfn2;
98 struct page *page, *end;
99
100 pfn1 = bank_pfn_start(bank);
101 pfn2 = bank_pfn_end(bank);
102
103 page = pfn_to_page(pfn1);
104 end = pfn_to_page(pfn2 - 1) + 1;
105
106 do {
107 total++;
108 if (PageReserved(page))
109 reserved++;
110 else if (PageSwapCache(page))
111 cached++;
112 else if (PageSlab(page))
113 slab++;
114 else if (!page_count(page))
115 free++;
116 else
117 shared += page_count(page) - 1;
118 page++;
119 } while (page < end);
120 }
121
122 printk("%d pages of RAM\n", total);
123 printk("%d free pages\n", free);
124 printk("%d reserved pages\n", reserved);
125 printk("%d slab pages\n", slab);
126 printk("%d pages shared\n", shared);
127 printk("%d pages swap cached\n", cached);
128}
129
130static void __init find_limits(unsigned long *min, unsigned long *max_low,
131 unsigned long *max_high)
132{
133 struct meminfo *mi = &meminfo;
134 int i;
135
136 /* This assumes the meminfo array is properly sorted */
137 *min = bank_pfn_start(&mi->bank[0]);
138 for_each_bank (i, mi)
139 if (mi->bank[i].highmem)
140 break;
141 *max_low = bank_pfn_end(&mi->bank[i - 1]);
142 *max_high = bank_pfn_end(&mi->bank[mi->nr_banks - 1]);
143}
144
145#ifdef CONFIG_ZONE_DMA
146
147phys_addr_t arm_dma_zone_size __read_mostly;
148EXPORT_SYMBOL(arm_dma_zone_size);
149
150/*
151 * The DMA mask corresponding to the maximum bus address allocatable
152 * using GFP_DMA. The default here places no restriction on DMA
153 * allocations. This must be the smallest DMA mask in the system,
154 * so a successful GFP_DMA allocation will always satisfy this.
155 */
156phys_addr_t arm_dma_limit;
157unsigned long arm_dma_pfn_limit;
158
159static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
160 unsigned long dma_size)
161{
162 if (size[0] <= dma_size)
163 return;
164
165 size[ZONE_NORMAL] = size[0] - dma_size;
166 size[ZONE_DMA] = dma_size;
167 hole[ZONE_NORMAL] = hole[0];
168 hole[ZONE_DMA] = 0;
169}
170#endif
171
172void __init setup_dma_zone(const struct machine_desc *mdesc)
173{
174#ifdef CONFIG_ZONE_DMA
175 if (mdesc->dma_zone_size) {
176 arm_dma_zone_size = mdesc->dma_zone_size;
177 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
178 } else
179 arm_dma_limit = 0xffffffff;
180 arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
181#endif
182}
183
184static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
185 unsigned long max_high)
186{
187 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
188 struct memblock_region *reg;
189
190 /*
191 * initialise the zones.
192 */
193 memset(zone_size, 0, sizeof(zone_size));
194
195 /*
196 * The memory size has already been determined. If we need
197 * to do anything fancy with the allocation of this memory
198 * to the zones, now is the time to do it.
199 */
200 zone_size[0] = max_low - min;
201#ifdef CONFIG_HIGHMEM
202 zone_size[ZONE_HIGHMEM] = max_high - max_low;
203#endif
204
205 /*
206 * Calculate the size of the holes.
207 * holes = node_size - sum(bank_sizes)
208 */
209 memcpy(zhole_size, zone_size, sizeof(zhole_size));
210 for_each_memblock(memory, reg) {
211 unsigned long start = memblock_region_memory_base_pfn(reg);
212 unsigned long end = memblock_region_memory_end_pfn(reg);
213
214 if (start < max_low) {
215 unsigned long low_end = min(end, max_low);
216 zhole_size[0] -= low_end - start;
217 }
218#ifdef CONFIG_HIGHMEM
219 if (end > max_low) {
220 unsigned long high_start = max(start, max_low);
221 zhole_size[ZONE_HIGHMEM] -= end - high_start;
222 }
223#endif
224 }
225
226#ifdef CONFIG_ZONE_DMA
227 /*
228 * Adjust the sizes according to any special requirements for
229 * this machine type.
230 */
231 if (arm_dma_zone_size)
232 arm_adjust_dma_zone(zone_size, zhole_size,
233 arm_dma_zone_size >> PAGE_SHIFT);
234#endif
235
236 free_area_init_node(0, zone_size, min, zhole_size);
237}
238
239#ifdef CONFIG_HAVE_ARCH_PFN_VALID
240int pfn_valid(unsigned long pfn)
241{
242 return memblock_is_memory(__pfn_to_phys(pfn));
243}
244EXPORT_SYMBOL(pfn_valid);
245#endif
246
247#ifndef CONFIG_SPARSEMEM
248static void __init arm_memory_present(void)
249{
250}
251#else
252static void __init arm_memory_present(void)
253{
254 struct memblock_region *reg;
255
256 for_each_memblock(memory, reg)
257 memory_present(0, memblock_region_memory_base_pfn(reg),
258 memblock_region_memory_end_pfn(reg));
259}
260#endif
261
262static bool arm_memblock_steal_permitted = true;
263
264phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
265{
266 phys_addr_t phys;
267
268 BUG_ON(!arm_memblock_steal_permitted);
269
270 phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
271 memblock_free(phys, size);
272 memblock_remove(phys, size);
273
274 return phys;
275}
276
277void __init arm_memblock_init(struct meminfo *mi,
278 const struct machine_desc *mdesc)
279{
280 int i;
281
282 for (i = 0; i < mi->nr_banks; i++)
283 memblock_add(mi->bank[i].start, mi->bank[i].size);
284
285 /* Register the kernel text, kernel data and initrd with memblock. */
286#ifdef CONFIG_XIP_KERNEL
287 memblock_reserve(__pa(_sdata), _end - _sdata);
288#else
289 memblock_reserve(__pa(_stext), _end - _stext);
290#endif
291#ifdef CONFIG_BLK_DEV_INITRD
292 /* FDT scan will populate initrd_start */
293 if (initrd_start && !phys_initrd_size) {
294 phys_initrd_start = __virt_to_phys(initrd_start);
295 phys_initrd_size = initrd_end - initrd_start;
296 }
297 initrd_start = initrd_end = 0;
298 if (phys_initrd_size &&
299 !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
300 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
301 (u64)phys_initrd_start, phys_initrd_size);
302 phys_initrd_start = phys_initrd_size = 0;
303 }
304 if (phys_initrd_size &&
305 memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
306 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
307 (u64)phys_initrd_start, phys_initrd_size);
308 phys_initrd_start = phys_initrd_size = 0;
309 }
310 if (phys_initrd_size) {
311 memblock_reserve(phys_initrd_start, phys_initrd_size);
312
313 /* Now convert initrd to virtual addresses */
314 initrd_start = __phys_to_virt(phys_initrd_start);
315 initrd_end = initrd_start + phys_initrd_size;
316 }
317#endif
318
319 arm_mm_memblock_reserve();
320 arm_dt_memblock_reserve();
321
322 /* reserve any platform specific memblock areas */
323 if (mdesc->reserve)
324 mdesc->reserve();
325
326 early_init_fdt_scan_reserved_mem();
327
328 /*
329 * reserve memory for DMA contigouos allocations,
330 * must come from DMA area inside low memory
331 */
332 dma_contiguous_reserve(min(arm_dma_limit, arm_lowmem_limit));
333
334 arm_memblock_steal_permitted = false;
335 memblock_dump_all();
336}
337
338void __init bootmem_init(void)
339{
340 unsigned long min, max_low, max_high;
341
342 memblock_allow_resize();
343 max_low = max_high = 0;
344
345 find_limits(&min, &max_low, &max_high);
346
347 /*
348 * Sparsemem tries to allocate bootmem in memory_present(),
349 * so must be done after the fixed reservations
350 */
351 arm_memory_present();
352
353 /*
354 * sparse_init() needs the bootmem allocator up and running.
355 */
356 sparse_init();
357
358 /*
359 * Now free the memory - free_area_init_node needs
360 * the sparse mem_map arrays initialized by sparse_init()
361 * for memmap_init_zone(), otherwise all PFNs are invalid.
362 */
363 zone_sizes_init(min, max_low, max_high);
364
365 /*
366 * This doesn't seem to be used by the Linux memory manager any
367 * more, but is used by ll_rw_block. If we can get rid of it, we
368 * also get rid of some of the stuff above as well.
369 */
370 min_low_pfn = min;
371 max_low_pfn = max_low;
372 max_pfn = max_high;
373}
374
375/*
376 * Poison init memory with an undefined instruction (ARM) or a branch to an
377 * undefined instruction (Thumb).
378 */
379static inline void poison_init_mem(void *s, size_t count)
380{
381 u32 *p = (u32 *)s;
382 for (; count != 0; count -= 4)
383 *p++ = 0xe7fddef0;
384}
385
386static inline void
387free_memmap(unsigned long start_pfn, unsigned long end_pfn)
388{
389 struct page *start_pg, *end_pg;
390 phys_addr_t pg, pgend;
391
392 /*
393 * Convert start_pfn/end_pfn to a struct page pointer.
394 */
395 start_pg = pfn_to_page(start_pfn - 1) + 1;
396 end_pg = pfn_to_page(end_pfn - 1) + 1;
397
398 /*
399 * Convert to physical addresses, and
400 * round start upwards and end downwards.
401 */
402 pg = PAGE_ALIGN(__pa(start_pg));
403 pgend = __pa(end_pg) & PAGE_MASK;
404
405 /*
406 * If there are free pages between these,
407 * free the section of the memmap array.
408 */
409 if (pg < pgend)
410 memblock_free_early(pg, pgend - pg);
411}
412
413/*
414 * The mem_map array can get very big. Free the unused area of the memory map.
415 */
416static void __init free_unused_memmap(struct meminfo *mi)
417{
418 unsigned long bank_start, prev_bank_end = 0;
419 unsigned int i;
420
421 /*
422 * This relies on each bank being in address order.
423 * The banks are sorted previously in bootmem_init().
424 */
425 for_each_bank(i, mi) {
426 struct membank *bank = &mi->bank[i];
427
428 bank_start = bank_pfn_start(bank);
429
430#ifdef CONFIG_SPARSEMEM
431 /*
432 * Take care not to free memmap entries that don't exist
433 * due to SPARSEMEM sections which aren't present.
434 */
435 bank_start = min(bank_start,
436 ALIGN(prev_bank_end, PAGES_PER_SECTION));
437#else
438 /*
439 * Align down here since the VM subsystem insists that the
440 * memmap entries are valid from the bank start aligned to
441 * MAX_ORDER_NR_PAGES.
442 */
443 bank_start = round_down(bank_start, MAX_ORDER_NR_PAGES);
444#endif
445 /*
446 * If we had a previous bank, and there is a space
447 * between the current bank and the previous, free it.
448 */
449 if (prev_bank_end && prev_bank_end < bank_start)
450 free_memmap(prev_bank_end, bank_start);
451
452 /*
453 * Align up here since the VM subsystem insists that the
454 * memmap entries are valid from the bank end aligned to
455 * MAX_ORDER_NR_PAGES.
456 */
457 prev_bank_end = ALIGN(bank_pfn_end(bank), MAX_ORDER_NR_PAGES);
458 }
459
460#ifdef CONFIG_SPARSEMEM
461 if (!IS_ALIGNED(prev_bank_end, PAGES_PER_SECTION))
462 free_memmap(prev_bank_end,
463 ALIGN(prev_bank_end, PAGES_PER_SECTION));
464#endif
465}
466
467#ifdef CONFIG_HIGHMEM
468static inline void free_area_high(unsigned long pfn, unsigned long end)
469{
470 for (; pfn < end; pfn++)
471 free_highmem_page(pfn_to_page(pfn));
472}
473#endif
474
475static void __init free_highpages(void)
476{
477#ifdef CONFIG_HIGHMEM
478 unsigned long max_low = max_low_pfn;
479 struct memblock_region *mem, *res;
480
481 /* set highmem page free */
482 for_each_memblock(memory, mem) {
483 unsigned long start = memblock_region_memory_base_pfn(mem);
484 unsigned long end = memblock_region_memory_end_pfn(mem);
485
486 /* Ignore complete lowmem entries */
487 if (end <= max_low)
488 continue;
489
490 /* Truncate partial highmem entries */
491 if (start < max_low)
492 start = max_low;
493
494 /* Find and exclude any reserved regions */
495 for_each_memblock(reserved, res) {
496 unsigned long res_start, res_end;
497
498 res_start = memblock_region_reserved_base_pfn(res);
499 res_end = memblock_region_reserved_end_pfn(res);
500
501 if (res_end < start)
502 continue;
503 if (res_start < start)
504 res_start = start;
505 if (res_start > end)
506 res_start = end;
507 if (res_end > end)
508 res_end = end;
509 if (res_start != start)
510 free_area_high(start, res_start);
511 start = res_end;
512 if (start == end)
513 break;
514 }
515
516 /* And now free anything which remains */
517 if (start < end)
518 free_area_high(start, end);
519 }
520#endif
521}
522
523/*
524 * mem_init() marks the free areas in the mem_map and tells us how much
525 * memory is free. This is done after various parts of the system have
526 * claimed their memory after the kernel image.
527 */
528void __init mem_init(void)
529{
530#ifdef CONFIG_HAVE_TCM
531 /* These pointers are filled in on TCM detection */
532 extern u32 dtcm_end;
533 extern u32 itcm_end;
534#endif
535
536 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
537
538 /* this will put all unused low memory onto the freelists */
539 free_unused_memmap(&meminfo);
540 free_all_bootmem();
541
542#ifdef CONFIG_SA1111
543 /* now that our DMA memory is actually so designated, we can free it */
544 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
545#endif
546
547 free_highpages();
548
549 mem_init_print_info(NULL);
550
551#define MLK(b, t) b, t, ((t) - (b)) >> 10
552#define MLM(b, t) b, t, ((t) - (b)) >> 20
553#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
554
555 printk(KERN_NOTICE "Virtual kernel memory layout:\n"
556 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n"
557#ifdef CONFIG_HAVE_TCM
558 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
559 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
560#endif
561 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
562 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
563 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
564#ifdef CONFIG_HIGHMEM
565 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n"
566#endif
567#ifdef CONFIG_MODULES
568 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n"
569#endif
570 " .text : 0x%p" " - 0x%p" " (%4d kB)\n"
571 " .init : 0x%p" " - 0x%p" " (%4d kB)\n"
572 " .data : 0x%p" " - 0x%p" " (%4d kB)\n"
573 " .bss : 0x%p" " - 0x%p" " (%4d kB)\n",
574
575 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
576 (PAGE_SIZE)),
577#ifdef CONFIG_HAVE_TCM
578 MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
579 MLK(ITCM_OFFSET, (unsigned long) itcm_end),
580#endif
581 MLK(FIXADDR_START, FIXADDR_TOP),
582 MLM(VMALLOC_START, VMALLOC_END),
583 MLM(PAGE_OFFSET, (unsigned long)high_memory),
584#ifdef CONFIG_HIGHMEM
585 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
586 (PAGE_SIZE)),
587#endif
588#ifdef CONFIG_MODULES
589 MLM(MODULES_VADDR, MODULES_END),
590#endif
591
592 MLK_ROUNDUP(_text, _etext),
593 MLK_ROUNDUP(__init_begin, __init_end),
594 MLK_ROUNDUP(_sdata, _edata),
595 MLK_ROUNDUP(__bss_start, __bss_stop));
596
597#undef MLK
598#undef MLM
599#undef MLK_ROUNDUP
600
601 /*
602 * Check boundaries twice: Some fundamental inconsistencies can
603 * be detected at build time already.
604 */
605#ifdef CONFIG_MMU
606 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
607 BUG_ON(TASK_SIZE > MODULES_VADDR);
608#endif
609
610#ifdef CONFIG_HIGHMEM
611 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
612 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
613#endif
614
615 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
616 extern int sysctl_overcommit_memory;
617 /*
618 * On a machine this small we won't get
619 * anywhere without overcommit, so turn
620 * it on by default.
621 */
622 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
623 }
624}
625
626void free_initmem(void)
627{
628#ifdef CONFIG_HAVE_TCM
629 extern char __tcm_start, __tcm_end;
630
631 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
632 free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
633#endif
634
635 poison_init_mem(__init_begin, __init_end - __init_begin);
636 if (!machine_is_integrator() && !machine_is_cintegrator())
637 free_initmem_default(-1);
638}
639
640#ifdef CONFIG_BLK_DEV_INITRD
641
642static int keep_initrd;
643
644void free_initrd_mem(unsigned long start, unsigned long end)
645{
646 if (!keep_initrd) {
647 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
648 free_reserved_area((void *)start, (void *)end, -1, "initrd");
649 }
650}
651
652static int __init keepinitrd_setup(char *__unused)
653{
654 keep_initrd = 1;
655 return 1;
656}
657
658__setup("keepinitrd", keepinitrd_setup);
659#endif