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v4.6
  1/*
  2 * Based on arch/arm/mm/init.c
  3 *
  4 * Copyright (C) 1995-2005 Russell King
  5 * Copyright (C) 2012 ARM Ltd.
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 18 */
 19
 20#include <linux/kernel.h>
 21#include <linux/export.h>
 22#include <linux/errno.h>
 23#include <linux/swap.h>
 24#include <linux/init.h>
 25#include <linux/bootmem.h>
 
 26#include <linux/mman.h>
 27#include <linux/nodemask.h>
 28#include <linux/initrd.h>
 29#include <linux/gfp.h>
 30#include <linux/memblock.h>
 31#include <linux/sort.h>
 32#include <linux/of_fdt.h>
 33#include <linux/dma-mapping.h>
 34#include <linux/dma-contiguous.h>
 35#include <linux/efi.h>
 36#include <linux/swiotlb.h>
 
 37
 38#include <asm/boot.h>
 39#include <asm/fixmap.h>
 40#include <asm/kasan.h>
 41#include <asm/kernel-pgtable.h>
 42#include <asm/memory.h>
 
 43#include <asm/sections.h>
 44#include <asm/setup.h>
 45#include <asm/sizes.h>
 46#include <asm/tlb.h>
 47#include <asm/alternative.h>
 48
 49#include "mm.h"
 50
 51/*
 52 * We need to be able to catch inadvertent references to memstart_addr
 53 * that occur (potentially in generic code) before arm64_memblock_init()
 54 * executes, which assigns it its actual value. So use a default value
 55 * that cannot be mistaken for a real physical address.
 56 */
 57s64 memstart_addr __read_mostly = -1;
 58phys_addr_t arm64_dma_phys_limit __read_mostly;
 59
 60#ifdef CONFIG_BLK_DEV_INITRD
 61static int __init early_initrd(char *p)
 62{
 63	unsigned long start, size;
 64	char *endp;
 65
 66	start = memparse(p, &endp);
 67	if (*endp == ',') {
 68		size = memparse(endp + 1, NULL);
 69
 70		initrd_start = start;
 71		initrd_end = start + size;
 72	}
 73	return 0;
 74}
 75early_param("initrd", early_initrd);
 76#endif
 77
 78/*
 79 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
 80 * currently assumes that for memory starting above 4G, 32-bit devices will
 81 * use a DMA offset.
 82 */
 83static phys_addr_t __init max_zone_dma_phys(void)
 84{
 85	phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
 86	return min(offset + (1ULL << 32), memblock_end_of_DRAM());
 87}
 88
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 89static void __init zone_sizes_init(unsigned long min, unsigned long max)
 90{
 91	struct memblock_region *reg;
 92	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
 93	unsigned long max_dma = min;
 94
 95	memset(zone_size, 0, sizeof(zone_size));
 96
 97	/* 4GB maximum for 32-bit only capable devices */
 98#ifdef CONFIG_ZONE_DMA
 99	max_dma = PFN_DOWN(arm64_dma_phys_limit);
100	zone_size[ZONE_DMA] = max_dma - min;
101#endif
102	zone_size[ZONE_NORMAL] = max - max_dma;
103
104	memcpy(zhole_size, zone_size, sizeof(zhole_size));
105
106	for_each_memblock(memory, reg) {
107		unsigned long start = memblock_region_memory_base_pfn(reg);
108		unsigned long end = memblock_region_memory_end_pfn(reg);
109
110		if (start >= max)
111			continue;
112
113#ifdef CONFIG_ZONE_DMA
114		if (start < max_dma) {
115			unsigned long dma_end = min(end, max_dma);
116			zhole_size[ZONE_DMA] -= dma_end - start;
117		}
118#endif
119		if (end > max_dma) {
120			unsigned long normal_end = min(end, max);
121			unsigned long normal_start = max(start, max_dma);
122			zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
123		}
124	}
125
126	free_area_init_node(0, zone_size, min, zhole_size);
127}
128
 
 
129#ifdef CONFIG_HAVE_ARCH_PFN_VALID
130int pfn_valid(unsigned long pfn)
131{
132	return memblock_is_map_memory(pfn << PAGE_SHIFT);
133}
134EXPORT_SYMBOL(pfn_valid);
135#endif
136
137#ifndef CONFIG_SPARSEMEM
138static void __init arm64_memory_present(void)
139{
140}
141#else
142static void __init arm64_memory_present(void)
143{
144	struct memblock_region *reg;
145
146	for_each_memblock(memory, reg)
147		memory_present(0, memblock_region_memory_base_pfn(reg),
148			       memblock_region_memory_end_pfn(reg));
 
 
 
149}
150#endif
151
152static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
153
154/*
155 * Limit the memory size that was specified via FDT.
156 */
157static int __init early_mem(char *p)
158{
159	if (!p)
160		return 1;
161
162	memory_limit = memparse(p, &p) & PAGE_MASK;
163	pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
164
165	return 0;
166}
167early_param("mem", early_mem);
168
169void __init arm64_memblock_init(void)
170{
171	const s64 linear_region_size = -(s64)PAGE_OFFSET;
172
173	/*
174	 * Ensure that the linear region takes up exactly half of the kernel
175	 * virtual address space. This way, we can distinguish a linear address
176	 * from a kernel/module/vmalloc address by testing a single bit.
177	 */
178	BUILD_BUG_ON(linear_region_size != BIT(VA_BITS - 1));
179
180	/*
181	 * Select a suitable value for the base of physical memory.
182	 */
183	memstart_addr = round_down(memblock_start_of_DRAM(),
184				   ARM64_MEMSTART_ALIGN);
185
186	/*
187	 * Remove the memory that we will not be able to cover with the
188	 * linear mapping. Take care not to clip the kernel which may be
189	 * high in memory.
190	 */
191	memblock_remove(max_t(u64, memstart_addr + linear_region_size, __pa(_end)),
192			ULLONG_MAX);
193	if (memblock_end_of_DRAM() > linear_region_size)
194		memblock_remove(0, memblock_end_of_DRAM() - linear_region_size);
 
 
 
 
195
196	/*
197	 * Apply the memory limit if it was set. Since the kernel may be loaded
198	 * high up in memory, add back the kernel region that must be accessible
199	 * via the linear mapping.
200	 */
201	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
202		memblock_enforce_memory_limit(memory_limit);
203		memblock_add(__pa(_text), (u64)(_end - _text));
204	}
205
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
206	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
207		extern u16 memstart_offset_seed;
208		u64 range = linear_region_size -
209			    (memblock_end_of_DRAM() - memblock_start_of_DRAM());
210
211		/*
212		 * If the size of the linear region exceeds, by a sufficient
213		 * margin, the size of the region that the available physical
214		 * memory spans, randomize the linear region as well.
215		 */
216		if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) {
217			range = range / ARM64_MEMSTART_ALIGN + 1;
218			memstart_addr -= ARM64_MEMSTART_ALIGN *
219					 ((range * memstart_offset_seed) >> 16);
220		}
221	}
222
223	/*
224	 * Register the kernel text, kernel data, initrd, and initial
225	 * pagetables with memblock.
226	 */
227	memblock_reserve(__pa(_text), _end - _text);
228#ifdef CONFIG_BLK_DEV_INITRD
229	if (initrd_start) {
230		memblock_reserve(initrd_start, initrd_end - initrd_start);
231
232		/* the generic initrd code expects virtual addresses */
233		initrd_start = __phys_to_virt(initrd_start);
234		initrd_end = __phys_to_virt(initrd_end);
235	}
236#endif
237
238	early_init_fdt_scan_reserved_mem();
239
240	/* 4GB maximum for 32-bit only capable devices */
241	if (IS_ENABLED(CONFIG_ZONE_DMA))
242		arm64_dma_phys_limit = max_zone_dma_phys();
243	else
244		arm64_dma_phys_limit = PHYS_MASK + 1;
245	dma_contiguous_reserve(arm64_dma_phys_limit);
246
247	memblock_allow_resize();
248	memblock_dump_all();
249}
250
251void __init bootmem_init(void)
252{
253	unsigned long min, max;
254
255	min = PFN_UP(memblock_start_of_DRAM());
256	max = PFN_DOWN(memblock_end_of_DRAM());
257
258	early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT);
259
 
 
 
260	/*
261	 * Sparsemem tries to allocate bootmem in memory_present(), so must be
262	 * done after the fixed reservations.
263	 */
264	arm64_memory_present();
265
266	sparse_init();
267	zone_sizes_init(min, max);
268
269	high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
270	max_pfn = max_low_pfn = max;
271}
272
273#ifndef CONFIG_SPARSEMEM_VMEMMAP
274static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
275{
276	struct page *start_pg, *end_pg;
277	unsigned long pg, pgend;
278
279	/*
280	 * Convert start_pfn/end_pfn to a struct page pointer.
281	 */
282	start_pg = pfn_to_page(start_pfn - 1) + 1;
283	end_pg = pfn_to_page(end_pfn - 1) + 1;
284
285	/*
286	 * Convert to physical addresses, and round start upwards and end
287	 * downwards.
288	 */
289	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
290	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
291
292	/*
293	 * If there are free pages between these, free the section of the
294	 * memmap array.
295	 */
296	if (pg < pgend)
297		free_bootmem(pg, pgend - pg);
298}
299
300/*
301 * The mem_map array can get very big. Free the unused area of the memory map.
302 */
303static void __init free_unused_memmap(void)
304{
305	unsigned long start, prev_end = 0;
306	struct memblock_region *reg;
307
308	for_each_memblock(memory, reg) {
309		start = __phys_to_pfn(reg->base);
310
311#ifdef CONFIG_SPARSEMEM
312		/*
313		 * Take care not to free memmap entries that don't exist due
314		 * to SPARSEMEM sections which aren't present.
315		 */
316		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
317#endif
318		/*
319		 * If we had a previous bank, and there is a space between the
320		 * current bank and the previous, free it.
321		 */
322		if (prev_end && prev_end < start)
323			free_memmap(prev_end, start);
324
325		/*
326		 * Align up here since the VM subsystem insists that the
327		 * memmap entries are valid from the bank end aligned to
328		 * MAX_ORDER_NR_PAGES.
329		 */
330		prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size),
331				 MAX_ORDER_NR_PAGES);
332	}
333
334#ifdef CONFIG_SPARSEMEM
335	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
336		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
337#endif
338}
339#endif	/* !CONFIG_SPARSEMEM_VMEMMAP */
340
341/*
342 * mem_init() marks the free areas in the mem_map and tells us how much memory
343 * is free.  This is done after various parts of the system have claimed their
344 * memory after the kernel image.
345 */
346void __init mem_init(void)
347{
348	swiotlb_init(1);
 
 
 
 
349
350	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
351
352#ifndef CONFIG_SPARSEMEM_VMEMMAP
353	free_unused_memmap();
354#endif
355	/* this will put all unused low memory onto the freelists */
356	free_all_bootmem();
357
358	mem_init_print_info(NULL);
359
360#define MLK(b, t) b, t, ((t) - (b)) >> 10
361#define MLM(b, t) b, t, ((t) - (b)) >> 20
362#define MLG(b, t) b, t, ((t) - (b)) >> 30
363#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
364
365	pr_notice("Virtual kernel memory layout:\n");
366#ifdef CONFIG_KASAN
367	pr_cont("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
368		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
369#endif
370	pr_cont("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
371		MLM(MODULES_VADDR, MODULES_END));
372	pr_cont("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
373		MLG(VMALLOC_START, VMALLOC_END));
374	pr_cont("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n"
375		"    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n"
376		"      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n"
377		"      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
378		MLK_ROUNDUP(_text, __start_rodata),
379		MLK_ROUNDUP(__start_rodata, _etext),
380		MLK_ROUNDUP(__init_begin, __init_end),
381		MLK_ROUNDUP(_sdata, _edata));
 
 
 
 
 
 
382#ifdef CONFIG_SPARSEMEM_VMEMMAP
383	pr_cont("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n"
384		"              0x%16lx - 0x%16lx   (%6ld MB actual)\n",
385		MLG(VMEMMAP_START,
386		    VMEMMAP_START + VMEMMAP_SIZE),
387		MLM((unsigned long)phys_to_page(memblock_start_of_DRAM()),
388		    (unsigned long)virt_to_page(high_memory)));
389#endif
390	pr_cont("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
391		MLK(FIXADDR_START, FIXADDR_TOP));
392	pr_cont("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
393		MLM(PCI_IO_START, PCI_IO_END));
394	pr_cont("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
395		MLM(__phys_to_virt(memblock_start_of_DRAM()),
396		    (unsigned long)high_memory));
397
398#undef MLK
399#undef MLM
400#undef MLK_ROUNDUP
401
402	/*
403	 * Check boundaries twice: Some fundamental inconsistencies can be
404	 * detected at build time already.
405	 */
406#ifdef CONFIG_COMPAT
407	BUILD_BUG_ON(TASK_SIZE_32			> TASK_SIZE_64);
408#endif
409
 
 
 
 
 
 
410	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
411		extern int sysctl_overcommit_memory;
412		/*
413		 * On a machine this small we won't get anywhere without
414		 * overcommit, so turn it on by default.
415		 */
416		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
417	}
418}
419
420void free_initmem(void)
421{
422	free_initmem_default(0);
423	fixup_init();
 
 
 
 
 
 
424}
425
426#ifdef CONFIG_BLK_DEV_INITRD
427
428static int keep_initrd __initdata;
429
430void __init free_initrd_mem(unsigned long start, unsigned long end)
431{
432	if (!keep_initrd)
433		free_reserved_area((void *)start, (void *)end, 0, "initrd");
434}
435
436static int __init keepinitrd_setup(char *__unused)
437{
438	keep_initrd = 1;
439	return 1;
440}
441
442__setup("keepinitrd", keepinitrd_setup);
443#endif
444
445/*
446 * Dump out memory limit information on panic.
447 */
448static int dump_mem_limit(struct notifier_block *self, unsigned long v, void *p)
449{
450	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
451		pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
452	} else {
453		pr_emerg("Memory Limit: none\n");
454	}
455	return 0;
456}
457
458static struct notifier_block mem_limit_notifier = {
459	.notifier_call = dump_mem_limit,
460};
461
462static int __init register_mem_limit_dumper(void)
463{
464	atomic_notifier_chain_register(&panic_notifier_list,
465				       &mem_limit_notifier);
466	return 0;
467}
468__initcall(register_mem_limit_dumper);
v4.10.11
  1/*
  2 * Based on arch/arm/mm/init.c
  3 *
  4 * Copyright (C) 1995-2005 Russell King
  5 * Copyright (C) 2012 ARM Ltd.
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 *
 11 * This program is distributed in the hope that it will be useful,
 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 14 * GNU General Public License for more details.
 15 *
 16 * You should have received a copy of the GNU General Public License
 17 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 18 */
 19
 20#include <linux/kernel.h>
 21#include <linux/export.h>
 22#include <linux/errno.h>
 23#include <linux/swap.h>
 24#include <linux/init.h>
 25#include <linux/bootmem.h>
 26#include <linux/cache.h>
 27#include <linux/mman.h>
 28#include <linux/nodemask.h>
 29#include <linux/initrd.h>
 30#include <linux/gfp.h>
 31#include <linux/memblock.h>
 32#include <linux/sort.h>
 33#include <linux/of_fdt.h>
 34#include <linux/dma-mapping.h>
 35#include <linux/dma-contiguous.h>
 36#include <linux/efi.h>
 37#include <linux/swiotlb.h>
 38#include <linux/vmalloc.h>
 39
 40#include <asm/boot.h>
 41#include <asm/fixmap.h>
 42#include <asm/kasan.h>
 43#include <asm/kernel-pgtable.h>
 44#include <asm/memory.h>
 45#include <asm/numa.h>
 46#include <asm/sections.h>
 47#include <asm/setup.h>
 48#include <asm/sizes.h>
 49#include <asm/tlb.h>
 50#include <asm/alternative.h>
 51
 
 
 52/*
 53 * We need to be able to catch inadvertent references to memstart_addr
 54 * that occur (potentially in generic code) before arm64_memblock_init()
 55 * executes, which assigns it its actual value. So use a default value
 56 * that cannot be mistaken for a real physical address.
 57 */
 58s64 memstart_addr __ro_after_init = -1;
 59phys_addr_t arm64_dma_phys_limit __ro_after_init;
 60
 61#ifdef CONFIG_BLK_DEV_INITRD
 62static int __init early_initrd(char *p)
 63{
 64	unsigned long start, size;
 65	char *endp;
 66
 67	start = memparse(p, &endp);
 68	if (*endp == ',') {
 69		size = memparse(endp + 1, NULL);
 70
 71		initrd_start = start;
 72		initrd_end = start + size;
 73	}
 74	return 0;
 75}
 76early_param("initrd", early_initrd);
 77#endif
 78
 79/*
 80 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
 81 * currently assumes that for memory starting above 4G, 32-bit devices will
 82 * use a DMA offset.
 83 */
 84static phys_addr_t __init max_zone_dma_phys(void)
 85{
 86	phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
 87	return min(offset + (1ULL << 32), memblock_end_of_DRAM());
 88}
 89
 90#ifdef CONFIG_NUMA
 91
 92static void __init zone_sizes_init(unsigned long min, unsigned long max)
 93{
 94	unsigned long max_zone_pfns[MAX_NR_ZONES]  = {0};
 95
 96	if (IS_ENABLED(CONFIG_ZONE_DMA))
 97		max_zone_pfns[ZONE_DMA] = PFN_DOWN(max_zone_dma_phys());
 98	max_zone_pfns[ZONE_NORMAL] = max;
 99
100	free_area_init_nodes(max_zone_pfns);
101}
102
103#else
104
105static void __init zone_sizes_init(unsigned long min, unsigned long max)
106{
107	struct memblock_region *reg;
108	unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
109	unsigned long max_dma = min;
110
111	memset(zone_size, 0, sizeof(zone_size));
112
113	/* 4GB maximum for 32-bit only capable devices */
114#ifdef CONFIG_ZONE_DMA
115	max_dma = PFN_DOWN(arm64_dma_phys_limit);
116	zone_size[ZONE_DMA] = max_dma - min;
117#endif
118	zone_size[ZONE_NORMAL] = max - max_dma;
119
120	memcpy(zhole_size, zone_size, sizeof(zhole_size));
121
122	for_each_memblock(memory, reg) {
123		unsigned long start = memblock_region_memory_base_pfn(reg);
124		unsigned long end = memblock_region_memory_end_pfn(reg);
125
126		if (start >= max)
127			continue;
128
129#ifdef CONFIG_ZONE_DMA
130		if (start < max_dma) {
131			unsigned long dma_end = min(end, max_dma);
132			zhole_size[ZONE_DMA] -= dma_end - start;
133		}
134#endif
135		if (end > max_dma) {
136			unsigned long normal_end = min(end, max);
137			unsigned long normal_start = max(start, max_dma);
138			zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
139		}
140	}
141
142	free_area_init_node(0, zone_size, min, zhole_size);
143}
144
145#endif /* CONFIG_NUMA */
146
147#ifdef CONFIG_HAVE_ARCH_PFN_VALID
148int pfn_valid(unsigned long pfn)
149{
150	return memblock_is_map_memory(pfn << PAGE_SHIFT);
151}
152EXPORT_SYMBOL(pfn_valid);
153#endif
154
155#ifndef CONFIG_SPARSEMEM
156static void __init arm64_memory_present(void)
157{
158}
159#else
160static void __init arm64_memory_present(void)
161{
162	struct memblock_region *reg;
163
164	for_each_memblock(memory, reg) {
165		int nid = memblock_get_region_node(reg);
166
167		memory_present(nid, memblock_region_memory_base_pfn(reg),
168				memblock_region_memory_end_pfn(reg));
169	}
170}
171#endif
172
173static phys_addr_t memory_limit = (phys_addr_t)ULLONG_MAX;
174
175/*
176 * Limit the memory size that was specified via FDT.
177 */
178static int __init early_mem(char *p)
179{
180	if (!p)
181		return 1;
182
183	memory_limit = memparse(p, &p) & PAGE_MASK;
184	pr_notice("Memory limited to %lldMB\n", memory_limit >> 20);
185
186	return 0;
187}
188early_param("mem", early_mem);
189
190void __init arm64_memblock_init(void)
191{
192	const s64 linear_region_size = -(s64)PAGE_OFFSET;
193
194	/*
195	 * Ensure that the linear region takes up exactly half of the kernel
196	 * virtual address space. This way, we can distinguish a linear address
197	 * from a kernel/module/vmalloc address by testing a single bit.
198	 */
199	BUILD_BUG_ON(linear_region_size != BIT(VA_BITS - 1));
200
201	/*
202	 * Select a suitable value for the base of physical memory.
203	 */
204	memstart_addr = round_down(memblock_start_of_DRAM(),
205				   ARM64_MEMSTART_ALIGN);
206
207	/*
208	 * Remove the memory that we will not be able to cover with the
209	 * linear mapping. Take care not to clip the kernel which may be
210	 * high in memory.
211	 */
212	memblock_remove(max_t(u64, memstart_addr + linear_region_size, __pa(_end)),
213			ULLONG_MAX);
214	if (memstart_addr + linear_region_size < memblock_end_of_DRAM()) {
215		/* ensure that memstart_addr remains sufficiently aligned */
216		memstart_addr = round_up(memblock_end_of_DRAM() - linear_region_size,
217					 ARM64_MEMSTART_ALIGN);
218		memblock_remove(0, memstart_addr);
219	}
220
221	/*
222	 * Apply the memory limit if it was set. Since the kernel may be loaded
223	 * high up in memory, add back the kernel region that must be accessible
224	 * via the linear mapping.
225	 */
226	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
227		memblock_mem_limit_remove_map(memory_limit);
228		memblock_add(__pa(_text), (u64)(_end - _text));
229	}
230
231	if (IS_ENABLED(CONFIG_BLK_DEV_INITRD) && initrd_start) {
232		/*
233		 * Add back the memory we just removed if it results in the
234		 * initrd to become inaccessible via the linear mapping.
235		 * Otherwise, this is a no-op
236		 */
237		u64 base = initrd_start & PAGE_MASK;
238		u64 size = PAGE_ALIGN(initrd_end) - base;
239
240		/*
241		 * We can only add back the initrd memory if we don't end up
242		 * with more memory than we can address via the linear mapping.
243		 * It is up to the bootloader to position the kernel and the
244		 * initrd reasonably close to each other (i.e., within 32 GB of
245		 * each other) so that all granule/#levels combinations can
246		 * always access both.
247		 */
248		if (WARN(base < memblock_start_of_DRAM() ||
249			 base + size > memblock_start_of_DRAM() +
250				       linear_region_size,
251			"initrd not fully accessible via the linear mapping -- please check your bootloader ...\n")) {
252			initrd_start = 0;
253		} else {
254			memblock_remove(base, size); /* clear MEMBLOCK_ flags */
255			memblock_add(base, size);
256			memblock_reserve(base, size);
257		}
258	}
259
260	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE)) {
261		extern u16 memstart_offset_seed;
262		u64 range = linear_region_size -
263			    (memblock_end_of_DRAM() - memblock_start_of_DRAM());
264
265		/*
266		 * If the size of the linear region exceeds, by a sufficient
267		 * margin, the size of the region that the available physical
268		 * memory spans, randomize the linear region as well.
269		 */
270		if (memstart_offset_seed > 0 && range >= ARM64_MEMSTART_ALIGN) {
271			range = range / ARM64_MEMSTART_ALIGN + 1;
272			memstart_addr -= ARM64_MEMSTART_ALIGN *
273					 ((range * memstart_offset_seed) >> 16);
274		}
275	}
276
277	/*
278	 * Register the kernel text, kernel data, initrd, and initial
279	 * pagetables with memblock.
280	 */
281	memblock_reserve(__pa(_text), _end - _text);
282#ifdef CONFIG_BLK_DEV_INITRD
283	if (initrd_start) {
284		memblock_reserve(initrd_start, initrd_end - initrd_start);
285
286		/* the generic initrd code expects virtual addresses */
287		initrd_start = __phys_to_virt(initrd_start);
288		initrd_end = __phys_to_virt(initrd_end);
289	}
290#endif
291
292	early_init_fdt_scan_reserved_mem();
293
294	/* 4GB maximum for 32-bit only capable devices */
295	if (IS_ENABLED(CONFIG_ZONE_DMA))
296		arm64_dma_phys_limit = max_zone_dma_phys();
297	else
298		arm64_dma_phys_limit = PHYS_MASK + 1;
299	dma_contiguous_reserve(arm64_dma_phys_limit);
300
301	memblock_allow_resize();
 
302}
303
304void __init bootmem_init(void)
305{
306	unsigned long min, max;
307
308	min = PFN_UP(memblock_start_of_DRAM());
309	max = PFN_DOWN(memblock_end_of_DRAM());
310
311	early_memtest(min << PAGE_SHIFT, max << PAGE_SHIFT);
312
313	max_pfn = max_low_pfn = max;
314
315	arm64_numa_init();
316	/*
317	 * Sparsemem tries to allocate bootmem in memory_present(), so must be
318	 * done after the fixed reservations.
319	 */
320	arm64_memory_present();
321
322	sparse_init();
323	zone_sizes_init(min, max);
324
325	high_memory = __va((max << PAGE_SHIFT) - 1) + 1;
326	memblock_dump_all();
327}
328
329#ifndef CONFIG_SPARSEMEM_VMEMMAP
330static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
331{
332	struct page *start_pg, *end_pg;
333	unsigned long pg, pgend;
334
335	/*
336	 * Convert start_pfn/end_pfn to a struct page pointer.
337	 */
338	start_pg = pfn_to_page(start_pfn - 1) + 1;
339	end_pg = pfn_to_page(end_pfn - 1) + 1;
340
341	/*
342	 * Convert to physical addresses, and round start upwards and end
343	 * downwards.
344	 */
345	pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
346	pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
347
348	/*
349	 * If there are free pages between these, free the section of the
350	 * memmap array.
351	 */
352	if (pg < pgend)
353		free_bootmem(pg, pgend - pg);
354}
355
356/*
357 * The mem_map array can get very big. Free the unused area of the memory map.
358 */
359static void __init free_unused_memmap(void)
360{
361	unsigned long start, prev_end = 0;
362	struct memblock_region *reg;
363
364	for_each_memblock(memory, reg) {
365		start = __phys_to_pfn(reg->base);
366
367#ifdef CONFIG_SPARSEMEM
368		/*
369		 * Take care not to free memmap entries that don't exist due
370		 * to SPARSEMEM sections which aren't present.
371		 */
372		start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
373#endif
374		/*
375		 * If we had a previous bank, and there is a space between the
376		 * current bank and the previous, free it.
377		 */
378		if (prev_end && prev_end < start)
379			free_memmap(prev_end, start);
380
381		/*
382		 * Align up here since the VM subsystem insists that the
383		 * memmap entries are valid from the bank end aligned to
384		 * MAX_ORDER_NR_PAGES.
385		 */
386		prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size),
387				 MAX_ORDER_NR_PAGES);
388	}
389
390#ifdef CONFIG_SPARSEMEM
391	if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
392		free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
393#endif
394}
395#endif	/* !CONFIG_SPARSEMEM_VMEMMAP */
396
397/*
398 * mem_init() marks the free areas in the mem_map and tells us how much memory
399 * is free.  This is done after various parts of the system have claimed their
400 * memory after the kernel image.
401 */
402void __init mem_init(void)
403{
404	if (swiotlb_force == SWIOTLB_FORCE ||
405	    max_pfn > (arm64_dma_phys_limit >> PAGE_SHIFT))
406		swiotlb_init(1);
407	else
408		swiotlb_force = SWIOTLB_NO_FORCE;
409
410	set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
411
412#ifndef CONFIG_SPARSEMEM_VMEMMAP
413	free_unused_memmap();
414#endif
415	/* this will put all unused low memory onto the freelists */
416	free_all_bootmem();
417
418	mem_init_print_info(NULL);
419
420#define MLK(b, t) b, t, ((t) - (b)) >> 10
421#define MLM(b, t) b, t, ((t) - (b)) >> 20
422#define MLG(b, t) b, t, ((t) - (b)) >> 30
423#define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
424
425	pr_notice("Virtual kernel memory layout:\n");
426#ifdef CONFIG_KASAN
427	pr_notice("    kasan   : 0x%16lx - 0x%16lx   (%6ld GB)\n",
428		MLG(KASAN_SHADOW_START, KASAN_SHADOW_END));
429#endif
430	pr_notice("    modules : 0x%16lx - 0x%16lx   (%6ld MB)\n",
431		MLM(MODULES_VADDR, MODULES_END));
432	pr_notice("    vmalloc : 0x%16lx - 0x%16lx   (%6ld GB)\n",
433		MLG(VMALLOC_START, VMALLOC_END));
434	pr_notice("      .text : 0x%p" " - 0x%p" "   (%6ld KB)\n",
435		MLK_ROUNDUP(_text, _etext));
436	pr_notice("    .rodata : 0x%p" " - 0x%p" "   (%6ld KB)\n",
437		MLK_ROUNDUP(__start_rodata, __init_begin));
438	pr_notice("      .init : 0x%p" " - 0x%p" "   (%6ld KB)\n",
439		MLK_ROUNDUP(__init_begin, __init_end));
440	pr_notice("      .data : 0x%p" " - 0x%p" "   (%6ld KB)\n",
441		MLK_ROUNDUP(_sdata, _edata));
442	pr_notice("       .bss : 0x%p" " - 0x%p" "   (%6ld KB)\n",
443		MLK_ROUNDUP(__bss_start, __bss_stop));
444	pr_notice("    fixed   : 0x%16lx - 0x%16lx   (%6ld KB)\n",
445		MLK(FIXADDR_START, FIXADDR_TOP));
446	pr_notice("    PCI I/O : 0x%16lx - 0x%16lx   (%6ld MB)\n",
447		MLM(PCI_IO_START, PCI_IO_END));
448#ifdef CONFIG_SPARSEMEM_VMEMMAP
449	pr_notice("    vmemmap : 0x%16lx - 0x%16lx   (%6ld GB maximum)\n",
450		MLG(VMEMMAP_START, VMEMMAP_START + VMEMMAP_SIZE));
451	pr_notice("              0x%16lx - 0x%16lx   (%6ld MB actual)\n",
 
452		MLM((unsigned long)phys_to_page(memblock_start_of_DRAM()),
453		    (unsigned long)virt_to_page(high_memory)));
454#endif
455	pr_notice("    memory  : 0x%16lx - 0x%16lx   (%6ld MB)\n",
 
 
 
 
456		MLM(__phys_to_virt(memblock_start_of_DRAM()),
457		    (unsigned long)high_memory));
458
459#undef MLK
460#undef MLM
461#undef MLK_ROUNDUP
462
463	/*
464	 * Check boundaries twice: Some fundamental inconsistencies can be
465	 * detected at build time already.
466	 */
467#ifdef CONFIG_COMPAT
468	BUILD_BUG_ON(TASK_SIZE_32			> TASK_SIZE_64);
469#endif
470
471	/*
472	 * Make sure we chose the upper bound of sizeof(struct page)
473	 * correctly.
474	 */
475	BUILD_BUG_ON(sizeof(struct page) > (1 << STRUCT_PAGE_MAX_SHIFT));
476
477	if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
478		extern int sysctl_overcommit_memory;
479		/*
480		 * On a machine this small we won't get anywhere without
481		 * overcommit, so turn it on by default.
482		 */
483		sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
484	}
485}
486
487void free_initmem(void)
488{
489	free_reserved_area(__va(__pa(__init_begin)), __va(__pa(__init_end)),
490			   0, "unused kernel");
491	/*
492	 * Unmap the __init region but leave the VM area in place. This
493	 * prevents the region from being reused for kernel modules, which
494	 * is not supported by kallsyms.
495	 */
496	unmap_kernel_range((u64)__init_begin, (u64)(__init_end - __init_begin));
497}
498
499#ifdef CONFIG_BLK_DEV_INITRD
500
501static int keep_initrd __initdata;
502
503void __init free_initrd_mem(unsigned long start, unsigned long end)
504{
505	if (!keep_initrd)
506		free_reserved_area((void *)start, (void *)end, 0, "initrd");
507}
508
509static int __init keepinitrd_setup(char *__unused)
510{
511	keep_initrd = 1;
512	return 1;
513}
514
515__setup("keepinitrd", keepinitrd_setup);
516#endif
517
518/*
519 * Dump out memory limit information on panic.
520 */
521static int dump_mem_limit(struct notifier_block *self, unsigned long v, void *p)
522{
523	if (memory_limit != (phys_addr_t)ULLONG_MAX) {
524		pr_emerg("Memory Limit: %llu MB\n", memory_limit >> 20);
525	} else {
526		pr_emerg("Memory Limit: none\n");
527	}
528	return 0;
529}
530
531static struct notifier_block mem_limit_notifier = {
532	.notifier_call = dump_mem_limit,
533};
534
535static int __init register_mem_limit_dumper(void)
536{
537	atomic_notifier_chain_register(&panic_notifier_list,
538				       &mem_limit_notifier);
539	return 0;
540}
541__initcall(register_mem_limit_dumper);