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 #include <linux/stop_machine.h>
26
27 #include <asm/cp15.h>
28 #include <asm/mach-types.h>
29 #include <asm/memblock.h>
30 #include <asm/prom.h>
31 #include <asm/sections.h>
32 #include <asm/setup.h>
33 #include <asm/system_info.h>
34 #include <asm/tlb.h>
35 #include <asm/fixmap.h>
36
37 #include <asm/mach/arch.h>
38 #include <asm/mach/map.h>
39
40 #include "mm.h"
41
42 #ifdef CONFIG_CPU_CP15_MMU
__clear_cr(unsigned long mask)43 unsigned long __init __clear_cr(unsigned long mask)
44 {
45 cr_alignment = cr_alignment & ~mask;
46 return cr_alignment;
47 }
48 #endif
49
50 static phys_addr_t phys_initrd_start __initdata = 0;
51 static unsigned long phys_initrd_size __initdata = 0;
52
early_initrd(char * p)53 static int __init early_initrd(char *p)
54 {
55 phys_addr_t start;
56 unsigned long size;
57 char *endp;
58
59 start = memparse(p, &endp);
60 if (*endp == ',') {
61 size = memparse(endp + 1, NULL);
62
63 phys_initrd_start = start;
64 phys_initrd_size = size;
65 }
66 return 0;
67 }
68 early_param("initrd", early_initrd);
69
parse_tag_initrd(const struct tag * tag)70 static int __init parse_tag_initrd(const struct tag *tag)
71 {
72 pr_warn("ATAG_INITRD is deprecated; "
73 "please update your bootloader.\n");
74 phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
75 phys_initrd_size = tag->u.initrd.size;
76 return 0;
77 }
78
79 __tagtable(ATAG_INITRD, parse_tag_initrd);
80
parse_tag_initrd2(const struct tag * tag)81 static int __init parse_tag_initrd2(const struct tag *tag)
82 {
83 phys_initrd_start = tag->u.initrd.start;
84 phys_initrd_size = tag->u.initrd.size;
85 return 0;
86 }
87
88 __tagtable(ATAG_INITRD2, parse_tag_initrd2);
89
find_limits(unsigned long * min,unsigned long * max_low,unsigned long * max_high)90 static void __init find_limits(unsigned long *min, unsigned long *max_low,
91 unsigned long *max_high)
92 {
93 *max_low = PFN_DOWN(memblock_get_current_limit());
94 *min = PFN_UP(memblock_start_of_DRAM());
95 *max_high = PFN_DOWN(memblock_end_of_DRAM());
96 }
97
98 #ifdef CONFIG_ZONE_DMA
99
100 phys_addr_t arm_dma_zone_size __read_mostly;
101 EXPORT_SYMBOL(arm_dma_zone_size);
102
103 /*
104 * The DMA mask corresponding to the maximum bus address allocatable
105 * using GFP_DMA. The default here places no restriction on DMA
106 * allocations. This must be the smallest DMA mask in the system,
107 * so a successful GFP_DMA allocation will always satisfy this.
108 */
109 phys_addr_t arm_dma_limit;
110 unsigned long arm_dma_pfn_limit;
111
arm_adjust_dma_zone(unsigned long * size,unsigned long * hole,unsigned long dma_size)112 static void __init arm_adjust_dma_zone(unsigned long *size, unsigned long *hole,
113 unsigned long dma_size)
114 {
115 if (size[0] <= dma_size)
116 return;
117
118 size[ZONE_NORMAL] = size[0] - dma_size;
119 size[ZONE_DMA] = dma_size;
120 hole[ZONE_NORMAL] = hole[0];
121 hole[ZONE_DMA] = 0;
122 }
123 #endif
124
setup_dma_zone(const struct machine_desc * mdesc)125 void __init setup_dma_zone(const struct machine_desc *mdesc)
126 {
127 #ifdef CONFIG_ZONE_DMA
128 if (mdesc->dma_zone_size) {
129 arm_dma_zone_size = mdesc->dma_zone_size;
130 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
131 } else
132 arm_dma_limit = 0xffffffff;
133 arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
134 #endif
135 }
136
zone_sizes_init(unsigned long min,unsigned long max_low,unsigned long max_high)137 static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
138 unsigned long max_high)
139 {
140 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
141 struct memblock_region *reg;
142
143 /*
144 * initialise the zones.
145 */
146 memset(zone_size, 0, sizeof(zone_size));
147
148 /*
149 * The memory size has already been determined. If we need
150 * to do anything fancy with the allocation of this memory
151 * to the zones, now is the time to do it.
152 */
153 zone_size[0] = max_low - min;
154 #ifdef CONFIG_HIGHMEM
155 zone_size[ZONE_HIGHMEM] = max_high - max_low;
156 #endif
157
158 /*
159 * Calculate the size of the holes.
160 * holes = node_size - sum(bank_sizes)
161 */
162 memcpy(zhole_size, zone_size, sizeof(zhole_size));
163 for_each_memblock(memory, reg) {
164 unsigned long start = memblock_region_memory_base_pfn(reg);
165 unsigned long end = memblock_region_memory_end_pfn(reg);
166
167 if (start < max_low) {
168 unsigned long low_end = min(end, max_low);
169 zhole_size[0] -= low_end - start;
170 }
171 #ifdef CONFIG_HIGHMEM
172 if (end > max_low) {
173 unsigned long high_start = max(start, max_low);
174 zhole_size[ZONE_HIGHMEM] -= end - high_start;
175 }
176 #endif
177 }
178
179 #ifdef CONFIG_ZONE_DMA
180 /*
181 * Adjust the sizes according to any special requirements for
182 * this machine type.
183 */
184 if (arm_dma_zone_size)
185 arm_adjust_dma_zone(zone_size, zhole_size,
186 arm_dma_zone_size >> PAGE_SHIFT);
187 #endif
188
189 free_area_init_node(0, zone_size, min, zhole_size);
190 }
191
192 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
pfn_valid(unsigned long pfn)193 int pfn_valid(unsigned long pfn)
194 {
195 return memblock_is_memory(__pfn_to_phys(pfn));
196 }
197 EXPORT_SYMBOL(pfn_valid);
198 #endif
199
200 #ifndef CONFIG_SPARSEMEM
arm_memory_present(void)201 static void __init arm_memory_present(void)
202 {
203 }
204 #else
arm_memory_present(void)205 static void __init arm_memory_present(void)
206 {
207 struct memblock_region *reg;
208
209 for_each_memblock(memory, reg)
210 memory_present(0, memblock_region_memory_base_pfn(reg),
211 memblock_region_memory_end_pfn(reg));
212 }
213 #endif
214
215 static bool arm_memblock_steal_permitted = true;
216
arm_memblock_steal(phys_addr_t size,phys_addr_t align)217 phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
218 {
219 phys_addr_t phys;
220
221 BUG_ON(!arm_memblock_steal_permitted);
222
223 phys = memblock_alloc_base(size, align, MEMBLOCK_ALLOC_ANYWHERE);
224 memblock_free(phys, size);
225 memblock_remove(phys, size);
226
227 return phys;
228 }
229
arm_memblock_init(const struct machine_desc * mdesc)230 void __init arm_memblock_init(const struct machine_desc *mdesc)
231 {
232 /* Register the kernel text, kernel data and initrd with memblock. */
233 #ifdef CONFIG_XIP_KERNEL
234 memblock_reserve(__pa(_sdata), _end - _sdata);
235 #else
236 memblock_reserve(__pa(_stext), _end - _stext);
237 #endif
238 #ifdef CONFIG_BLK_DEV_INITRD
239 /* FDT scan will populate initrd_start */
240 if (initrd_start && !phys_initrd_size) {
241 phys_initrd_start = __virt_to_phys(initrd_start);
242 phys_initrd_size = initrd_end - initrd_start;
243 }
244 initrd_start = initrd_end = 0;
245 if (phys_initrd_size &&
246 !memblock_is_region_memory(phys_initrd_start, phys_initrd_size)) {
247 pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region - disabling initrd\n",
248 (u64)phys_initrd_start, phys_initrd_size);
249 phys_initrd_start = phys_initrd_size = 0;
250 }
251 if (phys_initrd_size &&
252 memblock_is_region_reserved(phys_initrd_start, phys_initrd_size)) {
253 pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region - disabling initrd\n",
254 (u64)phys_initrd_start, phys_initrd_size);
255 phys_initrd_start = phys_initrd_size = 0;
256 }
257 if (phys_initrd_size) {
258 memblock_reserve(phys_initrd_start, phys_initrd_size);
259
260 /* Now convert initrd to virtual addresses */
261 initrd_start = __phys_to_virt(phys_initrd_start);
262 initrd_end = initrd_start + phys_initrd_size;
263 }
264 #endif
265
266 arm_mm_memblock_reserve();
267
268 /* reserve any platform specific memblock areas */
269 if (mdesc->reserve)
270 mdesc->reserve();
271
272 early_init_fdt_reserve_self();
273 early_init_fdt_scan_reserved_mem();
274
275 /* reserve memory for DMA contiguous allocations */
276 dma_contiguous_reserve(arm_dma_limit);
277
278 arm_memblock_steal_permitted = false;
279 memblock_dump_all();
280 }
281
bootmem_init(void)282 void __init bootmem_init(void)
283 {
284 unsigned long min, max_low, max_high;
285
286 memblock_allow_resize();
287 max_low = max_high = 0;
288
289 find_limits(&min, &max_low, &max_high);
290
291 early_memtest((phys_addr_t)min << PAGE_SHIFT,
292 (phys_addr_t)max_low << PAGE_SHIFT);
293
294 /*
295 * Sparsemem tries to allocate bootmem in memory_present(),
296 * so must be done after the fixed reservations
297 */
298 arm_memory_present();
299
300 /*
301 * sparse_init() needs the bootmem allocator up and running.
302 */
303 sparse_init();
304
305 /*
306 * Now free the memory - free_area_init_node needs
307 * the sparse mem_map arrays initialized by sparse_init()
308 * for memmap_init_zone(), otherwise all PFNs are invalid.
309 */
310 zone_sizes_init(min, max_low, max_high);
311
312 /*
313 * This doesn't seem to be used by the Linux memory manager any
314 * more, but is used by ll_rw_block. If we can get rid of it, we
315 * also get rid of some of the stuff above as well.
316 */
317 min_low_pfn = min;
318 max_low_pfn = max_low;
319 max_pfn = max_high;
320 }
321
322 /*
323 * Poison init memory with an undefined instruction (ARM) or a branch to an
324 * undefined instruction (Thumb).
325 */
poison_init_mem(void * s,size_t count)326 static inline void poison_init_mem(void *s, size_t count)
327 {
328 u32 *p = (u32 *)s;
329 for (; count != 0; count -= 4)
330 *p++ = 0xe7fddef0;
331 }
332
333 static inline void
free_memmap(unsigned long start_pfn,unsigned long end_pfn)334 free_memmap(unsigned long start_pfn, unsigned long end_pfn)
335 {
336 struct page *start_pg, *end_pg;
337 phys_addr_t pg, pgend;
338
339 /*
340 * Convert start_pfn/end_pfn to a struct page pointer.
341 */
342 start_pg = pfn_to_page(start_pfn - 1) + 1;
343 end_pg = pfn_to_page(end_pfn - 1) + 1;
344
345 /*
346 * Convert to physical addresses, and
347 * round start upwards and end downwards.
348 */
349 pg = PAGE_ALIGN(__pa(start_pg));
350 pgend = __pa(end_pg) & PAGE_MASK;
351
352 /*
353 * If there are free pages between these,
354 * free the section of the memmap array.
355 */
356 if (pg < pgend)
357 memblock_free_early(pg, pgend - pg);
358 }
359
360 /*
361 * The mem_map array can get very big. Free the unused area of the memory map.
362 */
free_unused_memmap(void)363 static void __init free_unused_memmap(void)
364 {
365 unsigned long start, prev_end = 0;
366 struct memblock_region *reg;
367
368 /*
369 * This relies on each bank being in address order.
370 * The banks are sorted previously in bootmem_init().
371 */
372 for_each_memblock(memory, reg) {
373 start = memblock_region_memory_base_pfn(reg);
374
375 #ifdef CONFIG_SPARSEMEM
376 /*
377 * Take care not to free memmap entries that don't exist
378 * due to SPARSEMEM sections which aren't present.
379 */
380 start = min(start,
381 ALIGN(prev_end, PAGES_PER_SECTION));
382 #else
383 /*
384 * Align down here since the VM subsystem insists that the
385 * memmap entries are valid from the bank start aligned to
386 * MAX_ORDER_NR_PAGES.
387 */
388 start = round_down(start, MAX_ORDER_NR_PAGES);
389 #endif
390 /*
391 * If we had a previous bank, and there is a space
392 * between the current bank and the previous, free it.
393 */
394 if (prev_end && prev_end < start)
395 free_memmap(prev_end, start);
396
397 /*
398 * Align up here since the VM subsystem insists that the
399 * memmap entries are valid from the bank end aligned to
400 * MAX_ORDER_NR_PAGES.
401 */
402 prev_end = ALIGN(memblock_region_memory_end_pfn(reg),
403 MAX_ORDER_NR_PAGES);
404 }
405
406 #ifdef CONFIG_SPARSEMEM
407 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
408 free_memmap(prev_end,
409 ALIGN(prev_end, PAGES_PER_SECTION));
410 #endif
411 }
412
413 #ifdef CONFIG_HIGHMEM
free_area_high(unsigned long pfn,unsigned long end)414 static inline void free_area_high(unsigned long pfn, unsigned long end)
415 {
416 for (; pfn < end; pfn++)
417 free_highmem_page(pfn_to_page(pfn));
418 }
419 #endif
420
free_highpages(void)421 static void __init free_highpages(void)
422 {
423 #ifdef CONFIG_HIGHMEM
424 unsigned long max_low = max_low_pfn;
425 struct memblock_region *mem, *res;
426
427 /* set highmem page free */
428 for_each_memblock(memory, mem) {
429 unsigned long start = memblock_region_memory_base_pfn(mem);
430 unsigned long end = memblock_region_memory_end_pfn(mem);
431
432 /* Ignore complete lowmem entries */
433 if (end <= max_low)
434 continue;
435
436 /* Truncate partial highmem entries */
437 if (start < max_low)
438 start = max_low;
439
440 /* Find and exclude any reserved regions */
441 for_each_memblock(reserved, res) {
442 unsigned long res_start, res_end;
443
444 res_start = memblock_region_reserved_base_pfn(res);
445 res_end = memblock_region_reserved_end_pfn(res);
446
447 if (res_end < start)
448 continue;
449 if (res_start < start)
450 res_start = start;
451 if (res_start > end)
452 res_start = end;
453 if (res_end > end)
454 res_end = end;
455 if (res_start != start)
456 free_area_high(start, res_start);
457 start = res_end;
458 if (start == end)
459 break;
460 }
461
462 /* And now free anything which remains */
463 if (start < end)
464 free_area_high(start, end);
465 }
466 #endif
467 }
468
469 /*
470 * mem_init() marks the free areas in the mem_map and tells us how much
471 * memory is free. This is done after various parts of the system have
472 * claimed their memory after the kernel image.
473 */
mem_init(void)474 void __init mem_init(void)
475 {
476 #ifdef CONFIG_HAVE_TCM
477 /* These pointers are filled in on TCM detection */
478 extern u32 dtcm_end;
479 extern u32 itcm_end;
480 #endif
481
482 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
483
484 /* this will put all unused low memory onto the freelists */
485 free_unused_memmap();
486 free_all_bootmem();
487
488 #ifdef CONFIG_SA1111
489 /* now that our DMA memory is actually so designated, we can free it */
490 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
491 #endif
492
493 free_highpages();
494
495 mem_init_print_info(NULL);
496
497 #define MLK(b, t) b, t, ((t) - (b)) >> 10
498 #define MLM(b, t) b, t, ((t) - (b)) >> 20
499 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
500
501 pr_notice("Virtual kernel memory layout:\n"
502 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n"
503 #ifdef CONFIG_HAVE_TCM
504 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
505 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
506 #endif
507 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
508 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
509 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
510 #ifdef CONFIG_HIGHMEM
511 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n"
512 #endif
513 #ifdef CONFIG_MODULES
514 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n"
515 #endif
516 " .text : 0x%p" " - 0x%p" " (%4td kB)\n"
517 " .init : 0x%p" " - 0x%p" " (%4td kB)\n"
518 " .data : 0x%p" " - 0x%p" " (%4td kB)\n"
519 " .bss : 0x%p" " - 0x%p" " (%4td kB)\n",
520
521 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
522 (PAGE_SIZE)),
523 #ifdef CONFIG_HAVE_TCM
524 MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
525 MLK(ITCM_OFFSET, (unsigned long) itcm_end),
526 #endif
527 MLK(FIXADDR_START, FIXADDR_END),
528 MLM(VMALLOC_START, VMALLOC_END),
529 MLM(PAGE_OFFSET, (unsigned long)high_memory),
530 #ifdef CONFIG_HIGHMEM
531 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
532 (PAGE_SIZE)),
533 #endif
534 #ifdef CONFIG_MODULES
535 MLM(MODULES_VADDR, MODULES_END),
536 #endif
537
538 MLK_ROUNDUP(_text, _etext),
539 MLK_ROUNDUP(__init_begin, __init_end),
540 MLK_ROUNDUP(_sdata, _edata),
541 MLK_ROUNDUP(__bss_start, __bss_stop));
542
543 #undef MLK
544 #undef MLM
545 #undef MLK_ROUNDUP
546
547 /*
548 * Check boundaries twice: Some fundamental inconsistencies can
549 * be detected at build time already.
550 */
551 #ifdef CONFIG_MMU
552 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
553 BUG_ON(TASK_SIZE > MODULES_VADDR);
554 #endif
555
556 #ifdef CONFIG_HIGHMEM
557 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
558 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
559 #endif
560
561 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
562 extern int sysctl_overcommit_memory;
563 /*
564 * On a machine this small we won't get
565 * anywhere without overcommit, so turn
566 * it on by default.
567 */
568 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
569 }
570 }
571
572 #ifdef CONFIG_ARM_KERNMEM_PERMS
573 struct section_perm {
574 unsigned long start;
575 unsigned long end;
576 pmdval_t mask;
577 pmdval_t prot;
578 pmdval_t clear;
579 };
580
581 static struct section_perm nx_perms[] = {
582 /* Make pages tables, etc before _stext RW (set NX). */
583 {
584 .start = PAGE_OFFSET,
585 .end = (unsigned long)_stext,
586 .mask = ~PMD_SECT_XN,
587 .prot = PMD_SECT_XN,
588 },
589 /* Make init RW (set NX). */
590 {
591 .start = (unsigned long)__init_begin,
592 .end = (unsigned long)_sdata,
593 .mask = ~PMD_SECT_XN,
594 .prot = PMD_SECT_XN,
595 },
596 #ifdef CONFIG_DEBUG_RODATA
597 /* Make rodata NX (set RO in ro_perms below). */
598 {
599 .start = (unsigned long)__start_rodata,
600 .end = (unsigned long)__init_begin,
601 .mask = ~PMD_SECT_XN,
602 .prot = PMD_SECT_XN,
603 },
604 #endif
605 };
606
607 #ifdef CONFIG_DEBUG_RODATA
608 static struct section_perm ro_perms[] = {
609 /* Make kernel code and rodata RX (set RO). */
610 {
611 .start = (unsigned long)_stext,
612 .end = (unsigned long)__init_begin,
613 #ifdef CONFIG_ARM_LPAE
614 .mask = ~(L_PMD_SECT_RDONLY | PMD_SECT_AP2),
615 .prot = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
616 #else
617 .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
618 .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE,
619 .clear = PMD_SECT_AP_WRITE,
620 #endif
621 },
622 };
623 #endif
624
625 /*
626 * Updates section permissions only for the current mm (sections are
627 * copied into each mm). During startup, this is the init_mm. Is only
628 * safe to be called with preemption disabled, as under stop_machine().
629 */
section_update(unsigned long addr,pmdval_t mask,pmdval_t prot,struct mm_struct * mm)630 static inline void section_update(unsigned long addr, pmdval_t mask,
631 pmdval_t prot, struct mm_struct *mm)
632 {
633 pmd_t *pmd;
634
635 pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
636
637 #ifdef CONFIG_ARM_LPAE
638 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
639 #else
640 if (addr & SECTION_SIZE)
641 pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
642 else
643 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
644 #endif
645 flush_pmd_entry(pmd);
646 local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
647 }
648
649 /* Make sure extended page tables are in use. */
arch_has_strict_perms(void)650 static inline bool arch_has_strict_perms(void)
651 {
652 if (cpu_architecture() < CPU_ARCH_ARMv6)
653 return false;
654
655 return !!(get_cr() & CR_XP);
656 }
657
set_section_perms(struct section_perm * perms,int n,bool set,struct mm_struct * mm)658 void set_section_perms(struct section_perm *perms, int n, bool set,
659 struct mm_struct *mm)
660 {
661 size_t i;
662 unsigned long addr;
663
664 if (!arch_has_strict_perms())
665 return;
666
667 for (i = 0; i < n; i++) {
668 if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
669 !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
670 pr_err("BUG: section %lx-%lx not aligned to %lx\n",
671 perms[i].start, perms[i].end,
672 SECTION_SIZE);
673 continue;
674 }
675
676 for (addr = perms[i].start;
677 addr < perms[i].end;
678 addr += SECTION_SIZE)
679 section_update(addr, perms[i].mask,
680 set ? perms[i].prot : perms[i].clear, mm);
681 }
682
683 }
684
update_sections_early(struct section_perm perms[],int n)685 static void update_sections_early(struct section_perm perms[], int n)
686 {
687 struct task_struct *t, *s;
688
689 read_lock(&tasklist_lock);
690 for_each_process(t) {
691 if (t->flags & PF_KTHREAD)
692 continue;
693 for_each_thread(t, s)
694 if (s->mm)
695 set_section_perms(perms, n, true, s->mm);
696 }
697 read_unlock(&tasklist_lock);
698 set_section_perms(perms, n, true, current->active_mm);
699 set_section_perms(perms, n, true, &init_mm);
700 }
701
__fix_kernmem_perms(void * unused)702 int __fix_kernmem_perms(void *unused)
703 {
704 update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
705 return 0;
706 }
707
fix_kernmem_perms(void)708 void fix_kernmem_perms(void)
709 {
710 stop_machine(__fix_kernmem_perms, NULL, NULL);
711 }
712
713 #ifdef CONFIG_DEBUG_RODATA
__mark_rodata_ro(void * unused)714 int __mark_rodata_ro(void *unused)
715 {
716 update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
717 return 0;
718 }
719
720 static int kernel_set_to_readonly __read_mostly;
721
mark_rodata_ro(void)722 void mark_rodata_ro(void)
723 {
724 kernel_set_to_readonly = 1;
725 stop_machine(__mark_rodata_ro, NULL, NULL);
726 }
727
set_kernel_text_rw(void)728 void set_kernel_text_rw(void)
729 {
730 if (!kernel_set_to_readonly)
731 return;
732
733 set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
734 current->active_mm);
735 }
736
set_kernel_text_ro(void)737 void set_kernel_text_ro(void)
738 {
739 if (!kernel_set_to_readonly)
740 return;
741
742 set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
743 current->active_mm);
744 }
745 #endif /* CONFIG_DEBUG_RODATA */
746
747 #else
fix_kernmem_perms(void)748 static inline void fix_kernmem_perms(void) { }
749 #endif /* CONFIG_ARM_KERNMEM_PERMS */
750
free_tcmmem(void)751 void free_tcmmem(void)
752 {
753 #ifdef CONFIG_HAVE_TCM
754 extern char __tcm_start, __tcm_end;
755
756 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
757 free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
758 #endif
759 }
760
free_initmem(void)761 void free_initmem(void)
762 {
763 fix_kernmem_perms();
764 free_tcmmem();
765
766 poison_init_mem(__init_begin, __init_end - __init_begin);
767 if (!machine_is_integrator() && !machine_is_cintegrator())
768 free_initmem_default(-1);
769 }
770
771 #ifdef CONFIG_BLK_DEV_INITRD
772
773 static int keep_initrd;
774
free_initrd_mem(unsigned long start,unsigned long end)775 void free_initrd_mem(unsigned long start, unsigned long end)
776 {
777 if (!keep_initrd) {
778 if (start == initrd_start)
779 start = round_down(start, PAGE_SIZE);
780 if (end == initrd_end)
781 end = round_up(end, PAGE_SIZE);
782
783 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
784 free_reserved_area((void *)start, (void *)end, -1, "initrd");
785 }
786 }
787
keepinitrd_setup(char * __unused)788 static int __init keepinitrd_setup(char *__unused)
789 {
790 keep_initrd = 1;
791 return 1;
792 }
793
794 __setup("keepinitrd", keepinitrd_setup);
795 #endif
796