Loading...
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/arch/arm/mm/init.c
4 *
5 * Copyright (C) 1995-2005 Russell King
6 */
7#include <linux/kernel.h>
8#include <linux/errno.h>
9#include <linux/swap.h>
10#include <linux/init.h>
11#include <linux/mman.h>
12#include <linux/sched/signal.h>
13#include <linux/sched/task.h>
14#include <linux/export.h>
15#include <linux/nodemask.h>
16#include <linux/initrd.h>
17#include <linux/of_fdt.h>
18#include <linux/highmem.h>
19#include <linux/gfp.h>
20#include <linux/memblock.h>
21#include <linux/dma-map-ops.h>
22#include <linux/sizes.h>
23#include <linux/stop_machine.h>
24#include <linux/swiotlb.h>
25
26#include <asm/cp15.h>
27#include <asm/mach-types.h>
28#include <asm/memblock.h>
29#include <asm/memory.h>
30#include <asm/prom.h>
31#include <asm/sections.h>
32#include <asm/setup.h>
33#include <asm/set_memory.h>
34#include <asm/system_info.h>
35#include <asm/tlb.h>
36#include <asm/fixmap.h>
37#include <asm/ptdump.h>
38
39#include <asm/mach/arch.h>
40#include <asm/mach/map.h>
41
42#include "mm.h"
43
44#ifdef CONFIG_CPU_CP15_MMU
45unsigned long __init __clear_cr(unsigned long mask)
46{
47 cr_alignment = cr_alignment & ~mask;
48 return cr_alignment;
49}
50#endif
51
52#ifdef CONFIG_BLK_DEV_INITRD
53static int __init parse_tag_initrd(const struct tag *tag)
54{
55 pr_warn("ATAG_INITRD is deprecated; "
56 "please update your bootloader.\n");
57 phys_initrd_start = __virt_to_phys(tag->u.initrd.start);
58 phys_initrd_size = tag->u.initrd.size;
59 return 0;
60}
61
62__tagtable(ATAG_INITRD, parse_tag_initrd);
63
64static int __init parse_tag_initrd2(const struct tag *tag)
65{
66 phys_initrd_start = tag->u.initrd.start;
67 phys_initrd_size = tag->u.initrd.size;
68 return 0;
69}
70
71__tagtable(ATAG_INITRD2, parse_tag_initrd2);
72#endif
73
74static void __init find_limits(unsigned long *min, unsigned long *max_low,
75 unsigned long *max_high)
76{
77 *max_low = PFN_DOWN(memblock_get_current_limit());
78 *min = PFN_UP(memblock_start_of_DRAM());
79 *max_high = PFN_DOWN(memblock_end_of_DRAM());
80}
81
82#ifdef CONFIG_ZONE_DMA
83
84phys_addr_t arm_dma_zone_size __read_mostly;
85EXPORT_SYMBOL(arm_dma_zone_size);
86
87/*
88 * The DMA mask corresponding to the maximum bus address allocatable
89 * using GFP_DMA. The default here places no restriction on DMA
90 * allocations. This must be the smallest DMA mask in the system,
91 * so a successful GFP_DMA allocation will always satisfy this.
92 */
93phys_addr_t arm_dma_limit;
94unsigned long arm_dma_pfn_limit;
95#endif
96
97void __init setup_dma_zone(const struct machine_desc *mdesc)
98{
99#ifdef CONFIG_ZONE_DMA
100 if (mdesc->dma_zone_size) {
101 arm_dma_zone_size = mdesc->dma_zone_size;
102 arm_dma_limit = PHYS_OFFSET + arm_dma_zone_size - 1;
103 } else
104 arm_dma_limit = 0xffffffff;
105 arm_dma_pfn_limit = arm_dma_limit >> PAGE_SHIFT;
106#endif
107}
108
109static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
110 unsigned long max_high)
111{
112 unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
113
114#ifdef CONFIG_ZONE_DMA
115 max_zone_pfn[ZONE_DMA] = min(arm_dma_pfn_limit, max_low);
116#endif
117 max_zone_pfn[ZONE_NORMAL] = max_low;
118#ifdef CONFIG_HIGHMEM
119 max_zone_pfn[ZONE_HIGHMEM] = max_high;
120#endif
121 free_area_init(max_zone_pfn);
122}
123
124#ifdef CONFIG_HAVE_ARCH_PFN_VALID
125int pfn_valid(unsigned long pfn)
126{
127 phys_addr_t addr = __pfn_to_phys(pfn);
128 unsigned long pageblock_size = PAGE_SIZE * pageblock_nr_pages;
129
130 if (__phys_to_pfn(addr) != pfn)
131 return 0;
132
133 /*
134 * If address less than pageblock_size bytes away from a present
135 * memory chunk there still will be a memory map entry for it
136 * because we round freed memory map to the pageblock boundaries.
137 */
138 if (memblock_overlaps_region(&memblock.memory,
139 ALIGN_DOWN(addr, pageblock_size),
140 pageblock_size))
141 return 1;
142
143 return 0;
144}
145EXPORT_SYMBOL(pfn_valid);
146#endif
147
148static bool arm_memblock_steal_permitted = true;
149
150phys_addr_t __init arm_memblock_steal(phys_addr_t size, phys_addr_t align)
151{
152 phys_addr_t phys;
153
154 BUG_ON(!arm_memblock_steal_permitted);
155
156 phys = memblock_phys_alloc(size, align);
157 if (!phys)
158 panic("Failed to steal %pa bytes at %pS\n",
159 &size, (void *)_RET_IP_);
160
161 memblock_phys_free(phys, size);
162 memblock_remove(phys, size);
163
164 return phys;
165}
166
167#ifdef CONFIG_CPU_ICACHE_MISMATCH_WORKAROUND
168void check_cpu_icache_size(int cpuid)
169{
170 u32 size, ctr;
171
172 asm("mrc p15, 0, %0, c0, c0, 1" : "=r" (ctr));
173
174 size = 1 << ((ctr & 0xf) + 2);
175 if (cpuid != 0 && icache_size != size)
176 pr_info("CPU%u: detected I-Cache line size mismatch, workaround enabled\n",
177 cpuid);
178 if (icache_size > size)
179 icache_size = size;
180}
181#endif
182
183void __init arm_memblock_init(const struct machine_desc *mdesc)
184{
185 /* Register the kernel text, kernel data and initrd with memblock. */
186 memblock_reserve(__pa(KERNEL_START), KERNEL_END - KERNEL_START);
187
188 reserve_initrd_mem();
189
190 arm_mm_memblock_reserve();
191
192 /* reserve any platform specific memblock areas */
193 if (mdesc->reserve)
194 mdesc->reserve();
195
196 early_init_fdt_scan_reserved_mem();
197
198 /* reserve memory for DMA contiguous allocations */
199 dma_contiguous_reserve(arm_dma_limit);
200
201 arm_memblock_steal_permitted = false;
202 memblock_dump_all();
203}
204
205void __init bootmem_init(void)
206{
207 memblock_allow_resize();
208
209 find_limits(&min_low_pfn, &max_low_pfn, &max_pfn);
210
211 early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT,
212 (phys_addr_t)max_low_pfn << PAGE_SHIFT);
213
214 /*
215 * sparse_init() tries to allocate memory from memblock, so must be
216 * done after the fixed reservations
217 */
218 sparse_init();
219
220 /*
221 * Now free the memory - free_area_init needs
222 * the sparse mem_map arrays initialized by sparse_init()
223 * for memmap_init_zone(), otherwise all PFNs are invalid.
224 */
225 zone_sizes_init(min_low_pfn, max_low_pfn, max_pfn);
226}
227
228/*
229 * Poison init memory with an undefined instruction (ARM) or a branch to an
230 * undefined instruction (Thumb).
231 */
232static inline void poison_init_mem(void *s, size_t count)
233{
234 u32 *p = (u32 *)s;
235 for (; count != 0; count -= 4)
236 *p++ = 0xe7fddef0;
237}
238
239static void __init free_highpages(void)
240{
241#ifdef CONFIG_HIGHMEM
242 unsigned long max_low = max_low_pfn;
243 phys_addr_t range_start, range_end;
244 u64 i;
245
246 /* set highmem page free */
247 for_each_free_mem_range(i, NUMA_NO_NODE, MEMBLOCK_NONE,
248 &range_start, &range_end, NULL) {
249 unsigned long start = PFN_UP(range_start);
250 unsigned long end = PFN_DOWN(range_end);
251
252 /* Ignore complete lowmem entries */
253 if (end <= max_low)
254 continue;
255
256 /* Truncate partial highmem entries */
257 if (start < max_low)
258 start = max_low;
259
260 for (; start < end; start++)
261 free_highmem_page(pfn_to_page(start));
262 }
263#endif
264}
265
266/*
267 * mem_init() marks the free areas in the mem_map and tells us how much
268 * memory is free. This is done after various parts of the system have
269 * claimed their memory after the kernel image.
270 */
271void __init mem_init(void)
272{
273#ifdef CONFIG_ARM_LPAE
274 swiotlb_init(max_pfn > arm_dma_pfn_limit, SWIOTLB_VERBOSE);
275#endif
276
277 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
278
279 /* this will put all unused low memory onto the freelists */
280 memblock_free_all();
281
282#ifdef CONFIG_SA1111
283 /* now that our DMA memory is actually so designated, we can free it */
284 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
285#endif
286
287 free_highpages();
288
289 /*
290 * Check boundaries twice: Some fundamental inconsistencies can
291 * be detected at build time already.
292 */
293#ifdef CONFIG_MMU
294 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
295 BUG_ON(TASK_SIZE > MODULES_VADDR);
296#endif
297
298#ifdef CONFIG_HIGHMEM
299 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
300 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
301#endif
302}
303
304#ifdef CONFIG_STRICT_KERNEL_RWX
305struct section_perm {
306 const char *name;
307 unsigned long start;
308 unsigned long end;
309 pmdval_t mask;
310 pmdval_t prot;
311 pmdval_t clear;
312};
313
314/* First section-aligned location at or after __start_rodata. */
315extern char __start_rodata_section_aligned[];
316
317static struct section_perm nx_perms[] = {
318 /* Make pages tables, etc before _stext RW (set NX). */
319 {
320 .name = "pre-text NX",
321 .start = PAGE_OFFSET,
322 .end = (unsigned long)_stext,
323 .mask = ~PMD_SECT_XN,
324 .prot = PMD_SECT_XN,
325 },
326 /* Make init RW (set NX). */
327 {
328 .name = "init NX",
329 .start = (unsigned long)__init_begin,
330 .end = (unsigned long)_sdata,
331 .mask = ~PMD_SECT_XN,
332 .prot = PMD_SECT_XN,
333 },
334 /* Make rodata NX (set RO in ro_perms below). */
335 {
336 .name = "rodata NX",
337 .start = (unsigned long)__start_rodata_section_aligned,
338 .end = (unsigned long)__init_begin,
339 .mask = ~PMD_SECT_XN,
340 .prot = PMD_SECT_XN,
341 },
342};
343
344static struct section_perm ro_perms[] = {
345 /* Make kernel code and rodata RX (set RO). */
346 {
347 .name = "text/rodata RO",
348 .start = (unsigned long)_stext,
349 .end = (unsigned long)__init_begin,
350#ifdef CONFIG_ARM_LPAE
351 .mask = ~(L_PMD_SECT_RDONLY | PMD_SECT_AP2),
352 .prot = L_PMD_SECT_RDONLY | PMD_SECT_AP2,
353#else
354 .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
355 .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE,
356 .clear = PMD_SECT_AP_WRITE,
357#endif
358 },
359};
360
361/*
362 * Updates section permissions only for the current mm (sections are
363 * copied into each mm). During startup, this is the init_mm. Is only
364 * safe to be called with preemption disabled, as under stop_machine().
365 */
366static inline void section_update(unsigned long addr, pmdval_t mask,
367 pmdval_t prot, struct mm_struct *mm)
368{
369 pmd_t *pmd;
370
371 pmd = pmd_offset(pud_offset(p4d_offset(pgd_offset(mm, addr), addr), addr), addr);
372
373#ifdef CONFIG_ARM_LPAE
374 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
375#else
376 if (addr & SECTION_SIZE)
377 pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
378 else
379 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
380#endif
381 flush_pmd_entry(pmd);
382 local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
383}
384
385/* Make sure extended page tables are in use. */
386static inline bool arch_has_strict_perms(void)
387{
388 if (cpu_architecture() < CPU_ARCH_ARMv6)
389 return false;
390
391 return !!(get_cr() & CR_XP);
392}
393
394static void set_section_perms(struct section_perm *perms, int n, bool set,
395 struct mm_struct *mm)
396{
397 size_t i;
398 unsigned long addr;
399
400 if (!arch_has_strict_perms())
401 return;
402
403 for (i = 0; i < n; i++) {
404 if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
405 !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
406 pr_err("BUG: %s section %lx-%lx not aligned to %lx\n",
407 perms[i].name, perms[i].start, perms[i].end,
408 SECTION_SIZE);
409 continue;
410 }
411
412 for (addr = perms[i].start;
413 addr < perms[i].end;
414 addr += SECTION_SIZE)
415 section_update(addr, perms[i].mask,
416 set ? perms[i].prot : perms[i].clear, mm);
417 }
418
419}
420
421/**
422 * update_sections_early intended to be called only through stop_machine
423 * framework and executed by only one CPU while all other CPUs will spin and
424 * wait, so no locking is required in this function.
425 */
426static void update_sections_early(struct section_perm perms[], int n)
427{
428 struct task_struct *t, *s;
429
430 for_each_process(t) {
431 if (t->flags & PF_KTHREAD)
432 continue;
433 for_each_thread(t, s)
434 if (s->mm)
435 set_section_perms(perms, n, true, s->mm);
436 }
437 set_section_perms(perms, n, true, current->active_mm);
438 set_section_perms(perms, n, true, &init_mm);
439}
440
441static int __fix_kernmem_perms(void *unused)
442{
443 update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
444 return 0;
445}
446
447static void fix_kernmem_perms(void)
448{
449 stop_machine(__fix_kernmem_perms, NULL, NULL);
450}
451
452static int __mark_rodata_ro(void *unused)
453{
454 update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
455 return 0;
456}
457
458void mark_rodata_ro(void)
459{
460 stop_machine(__mark_rodata_ro, NULL, NULL);
461 debug_checkwx();
462}
463
464#else
465static inline void fix_kernmem_perms(void) { }
466#endif /* CONFIG_STRICT_KERNEL_RWX */
467
468void free_initmem(void)
469{
470 fix_kernmem_perms();
471
472 poison_init_mem(__init_begin, __init_end - __init_begin);
473 if (!machine_is_integrator() && !machine_is_cintegrator())
474 free_initmem_default(-1);
475}
476
477#ifdef CONFIG_BLK_DEV_INITRD
478void free_initrd_mem(unsigned long start, unsigned long end)
479{
480 if (start == initrd_start)
481 start = round_down(start, PAGE_SIZE);
482 if (end == initrd_end)
483 end = round_up(end, PAGE_SIZE);
484
485 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
486 free_reserved_area((void *)start, (void *)end, -1, "initrd");
487}
488#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#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
43unsigned long __init __clear_cr(unsigned long mask)
44{
45 cr_alignment = cr_alignment & ~mask;
46 return cr_alignment;
47}
48#endif
49
50static phys_addr_t phys_initrd_start __initdata = 0;
51static unsigned long phys_initrd_size __initdata = 0;
52
53static 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}
68early_param("initrd", early_initrd);
69
70static 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
81static 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
90static 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
100phys_addr_t arm_dma_zone_size __read_mostly;
101EXPORT_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 */
109phys_addr_t arm_dma_limit;
110unsigned long arm_dma_pfn_limit;
111
112static 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
125void __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
137static 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
193int pfn_valid(unsigned long pfn)
194{
195 return memblock_is_map_memory(__pfn_to_phys(pfn));
196}
197EXPORT_SYMBOL(pfn_valid);
198#endif
199
200#ifndef CONFIG_SPARSEMEM
201static void __init arm_memory_present(void)
202{
203}
204#else
205static 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
215static bool arm_memblock_steal_permitted = true;
216
217phys_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
230void __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
282void __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 */
326static 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
333static inline void
334free_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 */
363static 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
414static 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
421static 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 if (memblock_is_nomap(mem))
437 continue;
438
439 /* Truncate partial highmem entries */
440 if (start < max_low)
441 start = max_low;
442
443 /* Find and exclude any reserved regions */
444 for_each_memblock(reserved, res) {
445 unsigned long res_start, res_end;
446
447 res_start = memblock_region_reserved_base_pfn(res);
448 res_end = memblock_region_reserved_end_pfn(res);
449
450 if (res_end < start)
451 continue;
452 if (res_start < start)
453 res_start = start;
454 if (res_start > end)
455 res_start = end;
456 if (res_end > end)
457 res_end = end;
458 if (res_start != start)
459 free_area_high(start, res_start);
460 start = res_end;
461 if (start == end)
462 break;
463 }
464
465 /* And now free anything which remains */
466 if (start < end)
467 free_area_high(start, end);
468 }
469#endif
470}
471
472/*
473 * mem_init() marks the free areas in the mem_map and tells us how much
474 * memory is free. This is done after various parts of the system have
475 * claimed their memory after the kernel image.
476 */
477void __init mem_init(void)
478{
479#ifdef CONFIG_HAVE_TCM
480 /* These pointers are filled in on TCM detection */
481 extern u32 dtcm_end;
482 extern u32 itcm_end;
483#endif
484
485 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
486
487 /* this will put all unused low memory onto the freelists */
488 free_unused_memmap();
489 free_all_bootmem();
490
491#ifdef CONFIG_SA1111
492 /* now that our DMA memory is actually so designated, we can free it */
493 free_reserved_area(__va(PHYS_OFFSET), swapper_pg_dir, -1, NULL);
494#endif
495
496 free_highpages();
497
498 mem_init_print_info(NULL);
499
500#define MLK(b, t) b, t, ((t) - (b)) >> 10
501#define MLM(b, t) b, t, ((t) - (b)) >> 20
502#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
503
504 pr_notice("Virtual kernel memory layout:\n"
505 " vector : 0x%08lx - 0x%08lx (%4ld kB)\n"
506#ifdef CONFIG_HAVE_TCM
507 " DTCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
508 " ITCM : 0x%08lx - 0x%08lx (%4ld kB)\n"
509#endif
510 " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
511 " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
512 " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
513#ifdef CONFIG_HIGHMEM
514 " pkmap : 0x%08lx - 0x%08lx (%4ld MB)\n"
515#endif
516#ifdef CONFIG_MODULES
517 " modules : 0x%08lx - 0x%08lx (%4ld MB)\n"
518#endif
519 " .text : 0x%p" " - 0x%p" " (%4td kB)\n"
520 " .init : 0x%p" " - 0x%p" " (%4td kB)\n"
521 " .data : 0x%p" " - 0x%p" " (%4td kB)\n"
522 " .bss : 0x%p" " - 0x%p" " (%4td kB)\n",
523
524 MLK(UL(CONFIG_VECTORS_BASE), UL(CONFIG_VECTORS_BASE) +
525 (PAGE_SIZE)),
526#ifdef CONFIG_HAVE_TCM
527 MLK(DTCM_OFFSET, (unsigned long) dtcm_end),
528 MLK(ITCM_OFFSET, (unsigned long) itcm_end),
529#endif
530 MLK(FIXADDR_START, FIXADDR_END),
531 MLM(VMALLOC_START, VMALLOC_END),
532 MLM(PAGE_OFFSET, (unsigned long)high_memory),
533#ifdef CONFIG_HIGHMEM
534 MLM(PKMAP_BASE, (PKMAP_BASE) + (LAST_PKMAP) *
535 (PAGE_SIZE)),
536#endif
537#ifdef CONFIG_MODULES
538 MLM(MODULES_VADDR, MODULES_END),
539#endif
540
541 MLK_ROUNDUP(_text, _etext),
542 MLK_ROUNDUP(__init_begin, __init_end),
543 MLK_ROUNDUP(_sdata, _edata),
544 MLK_ROUNDUP(__bss_start, __bss_stop));
545
546#undef MLK
547#undef MLM
548#undef MLK_ROUNDUP
549
550 /*
551 * Check boundaries twice: Some fundamental inconsistencies can
552 * be detected at build time already.
553 */
554#ifdef CONFIG_MMU
555 BUILD_BUG_ON(TASK_SIZE > MODULES_VADDR);
556 BUG_ON(TASK_SIZE > MODULES_VADDR);
557#endif
558
559#ifdef CONFIG_HIGHMEM
560 BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
561 BUG_ON(PKMAP_BASE + LAST_PKMAP * PAGE_SIZE > PAGE_OFFSET);
562#endif
563
564 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
565 extern int sysctl_overcommit_memory;
566 /*
567 * On a machine this small we won't get
568 * anywhere without overcommit, so turn
569 * it on by default.
570 */
571 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
572 }
573}
574
575#ifdef CONFIG_DEBUG_RODATA
576struct section_perm {
577 const char *name;
578 unsigned long start;
579 unsigned long end;
580 pmdval_t mask;
581 pmdval_t prot;
582 pmdval_t clear;
583};
584
585/* First section-aligned location at or after __start_rodata. */
586extern char __start_rodata_section_aligned[];
587
588static struct section_perm nx_perms[] = {
589 /* Make pages tables, etc before _stext RW (set NX). */
590 {
591 .name = "pre-text NX",
592 .start = PAGE_OFFSET,
593 .end = (unsigned long)_stext,
594 .mask = ~PMD_SECT_XN,
595 .prot = PMD_SECT_XN,
596 },
597 /* Make init RW (set NX). */
598 {
599 .name = "init NX",
600 .start = (unsigned long)__init_begin,
601 .end = (unsigned long)_sdata,
602 .mask = ~PMD_SECT_XN,
603 .prot = PMD_SECT_XN,
604 },
605 /* Make rodata NX (set RO in ro_perms below). */
606 {
607 .name = "rodata NX",
608 .start = (unsigned long)__start_rodata_section_aligned,
609 .end = (unsigned long)__init_begin,
610 .mask = ~PMD_SECT_XN,
611 .prot = PMD_SECT_XN,
612 },
613};
614
615static struct section_perm ro_perms[] = {
616 /* Make kernel code and rodata RX (set RO). */
617 {
618 .name = "text/rodata RO",
619 .start = (unsigned long)_stext,
620 .end = (unsigned long)__init_begin,
621#ifdef CONFIG_ARM_LPAE
622 .mask = ~L_PMD_SECT_RDONLY,
623 .prot = L_PMD_SECT_RDONLY,
624#else
625 .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE),
626 .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE,
627 .clear = PMD_SECT_AP_WRITE,
628#endif
629 },
630};
631
632/*
633 * Updates section permissions only for the current mm (sections are
634 * copied into each mm). During startup, this is the init_mm. Is only
635 * safe to be called with preemption disabled, as under stop_machine().
636 */
637static inline void section_update(unsigned long addr, pmdval_t mask,
638 pmdval_t prot, struct mm_struct *mm)
639{
640 pmd_t *pmd;
641
642 pmd = pmd_offset(pud_offset(pgd_offset(mm, addr), addr), addr);
643
644#ifdef CONFIG_ARM_LPAE
645 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
646#else
647 if (addr & SECTION_SIZE)
648 pmd[1] = __pmd((pmd_val(pmd[1]) & mask) | prot);
649 else
650 pmd[0] = __pmd((pmd_val(pmd[0]) & mask) | prot);
651#endif
652 flush_pmd_entry(pmd);
653 local_flush_tlb_kernel_range(addr, addr + SECTION_SIZE);
654}
655
656/* Make sure extended page tables are in use. */
657static inline bool arch_has_strict_perms(void)
658{
659 if (cpu_architecture() < CPU_ARCH_ARMv6)
660 return false;
661
662 return !!(get_cr() & CR_XP);
663}
664
665void set_section_perms(struct section_perm *perms, int n, bool set,
666 struct mm_struct *mm)
667{
668 size_t i;
669 unsigned long addr;
670
671 if (!arch_has_strict_perms())
672 return;
673
674 for (i = 0; i < n; i++) {
675 if (!IS_ALIGNED(perms[i].start, SECTION_SIZE) ||
676 !IS_ALIGNED(perms[i].end, SECTION_SIZE)) {
677 pr_err("BUG: %s section %lx-%lx not aligned to %lx\n",
678 perms[i].name, perms[i].start, perms[i].end,
679 SECTION_SIZE);
680 continue;
681 }
682
683 for (addr = perms[i].start;
684 addr < perms[i].end;
685 addr += SECTION_SIZE)
686 section_update(addr, perms[i].mask,
687 set ? perms[i].prot : perms[i].clear, mm);
688 }
689
690}
691
692static void update_sections_early(struct section_perm perms[], int n)
693{
694 struct task_struct *t, *s;
695
696 read_lock(&tasklist_lock);
697 for_each_process(t) {
698 if (t->flags & PF_KTHREAD)
699 continue;
700 for_each_thread(t, s)
701 set_section_perms(perms, n, true, s->mm);
702 }
703 read_unlock(&tasklist_lock);
704 set_section_perms(perms, n, true, current->active_mm);
705 set_section_perms(perms, n, true, &init_mm);
706}
707
708int __fix_kernmem_perms(void *unused)
709{
710 update_sections_early(nx_perms, ARRAY_SIZE(nx_perms));
711 return 0;
712}
713
714void fix_kernmem_perms(void)
715{
716 stop_machine(__fix_kernmem_perms, NULL, NULL);
717}
718
719int __mark_rodata_ro(void *unused)
720{
721 update_sections_early(ro_perms, ARRAY_SIZE(ro_perms));
722 return 0;
723}
724
725void mark_rodata_ro(void)
726{
727 stop_machine(__mark_rodata_ro, NULL, NULL);
728}
729
730void set_kernel_text_rw(void)
731{
732 set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), false,
733 current->active_mm);
734}
735
736void set_kernel_text_ro(void)
737{
738 set_section_perms(ro_perms, ARRAY_SIZE(ro_perms), true,
739 current->active_mm);
740}
741
742#else
743static inline void fix_kernmem_perms(void) { }
744#endif /* CONFIG_DEBUG_RODATA */
745
746void free_tcmmem(void)
747{
748#ifdef CONFIG_HAVE_TCM
749 extern char __tcm_start, __tcm_end;
750
751 poison_init_mem(&__tcm_start, &__tcm_end - &__tcm_start);
752 free_reserved_area(&__tcm_start, &__tcm_end, -1, "TCM link");
753#endif
754}
755
756void free_initmem(void)
757{
758 fix_kernmem_perms();
759 free_tcmmem();
760
761 poison_init_mem(__init_begin, __init_end - __init_begin);
762 if (!machine_is_integrator() && !machine_is_cintegrator())
763 free_initmem_default(-1);
764}
765
766#ifdef CONFIG_BLK_DEV_INITRD
767
768static int keep_initrd;
769
770void free_initrd_mem(unsigned long start, unsigned long end)
771{
772 if (!keep_initrd) {
773 if (start == initrd_start)
774 start = round_down(start, PAGE_SIZE);
775 if (end == initrd_end)
776 end = round_up(end, PAGE_SIZE);
777
778 poison_init_mem((void *)start, PAGE_ALIGN(end) - start);
779 free_reserved_area((void *)start, (void *)end, -1, "initrd");
780 }
781}
782
783static int __init keepinitrd_setup(char *__unused)
784{
785 keep_initrd = 1;
786 return 1;
787}
788
789__setup("keepinitrd", keepinitrd_setup);
790#endif