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
37 #include <asm/fixmap.h>
38 #include <asm/sections.h>
39 #include <asm/setup.h>
40 #include <asm/sizes.h>
41 #include <asm/tlb.h>
42 #include <asm/alternative.h>
43
44 #include "mm.h"
45
46 phys_addr_t memstart_addr __read_mostly = 0;
47
48 #ifdef CONFIG_BLK_DEV_INITRD
early_initrd(char * p)49 static int __init early_initrd(char *p)
50 {
51 unsigned long start, size;
52 char *endp;
53
54 start = memparse(p, &endp);
55 if (*endp == ',') {
56 size = memparse(endp + 1, NULL);
57
58 initrd_start = (unsigned long)__va(start);
59 initrd_end = (unsigned long)__va(start + size);
60 }
61 return 0;
62 }
63 early_param("initrd", early_initrd);
64 #endif
65
66 /*
67 * Return the maximum physical address for ZONE_DMA (DMA_BIT_MASK(32)). It
68 * currently assumes that for memory starting above 4G, 32-bit devices will
69 * use a DMA offset.
70 */
max_zone_dma_phys(void)71 static phys_addr_t __init max_zone_dma_phys(void)
72 {
73 phys_addr_t offset = memblock_start_of_DRAM() & GENMASK_ULL(63, 32);
74 return min(offset + (1ULL << 32), memblock_end_of_DRAM());
75 }
76
zone_sizes_init(unsigned long min,unsigned long max)77 static void __init zone_sizes_init(unsigned long min, unsigned long max)
78 {
79 struct memblock_region *reg;
80 unsigned long zone_size[MAX_NR_ZONES], zhole_size[MAX_NR_ZONES];
81 unsigned long max_dma = min;
82
83 memset(zone_size, 0, sizeof(zone_size));
84
85 /* 4GB maximum for 32-bit only capable devices */
86 if (IS_ENABLED(CONFIG_ZONE_DMA)) {
87 max_dma = PFN_DOWN(max_zone_dma_phys());
88 zone_size[ZONE_DMA] = max_dma - min;
89 }
90 zone_size[ZONE_NORMAL] = max - max_dma;
91
92 memcpy(zhole_size, zone_size, sizeof(zhole_size));
93
94 for_each_memblock(memory, reg) {
95 unsigned long start = memblock_region_memory_base_pfn(reg);
96 unsigned long end = memblock_region_memory_end_pfn(reg);
97
98 if (start >= max)
99 continue;
100
101 if (IS_ENABLED(CONFIG_ZONE_DMA) && start < max_dma) {
102 unsigned long dma_end = min(end, max_dma);
103 zhole_size[ZONE_DMA] -= dma_end - start;
104 }
105
106 if (end > max_dma) {
107 unsigned long normal_end = min(end, max);
108 unsigned long normal_start = max(start, max_dma);
109 zhole_size[ZONE_NORMAL] -= normal_end - normal_start;
110 }
111 }
112
113 free_area_init_node(0, zone_size, min, zhole_size);
114 }
115
116 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
117 #define PFN_MASK ((1UL << (64 - PAGE_SHIFT)) - 1)
118
pfn_valid(unsigned long pfn)119 int pfn_valid(unsigned long pfn)
120 {
121 return (pfn & PFN_MASK) == pfn && memblock_is_memory(pfn << PAGE_SHIFT);
122 }
123 EXPORT_SYMBOL(pfn_valid);
124 #endif
125
126 #ifndef CONFIG_SPARSEMEM
arm64_memory_present(void)127 static void __init arm64_memory_present(void)
128 {
129 }
130 #else
arm64_memory_present(void)131 static void __init arm64_memory_present(void)
132 {
133 struct memblock_region *reg;
134
135 for_each_memblock(memory, reg)
136 memory_present(0, memblock_region_memory_base_pfn(reg),
137 memblock_region_memory_end_pfn(reg));
138 }
139 #endif
140
arm64_memblock_init(void)141 void __init arm64_memblock_init(void)
142 {
143 phys_addr_t dma_phys_limit = 0;
144
145 /*
146 * Register the kernel text, kernel data, initrd, and initial
147 * pagetables with memblock.
148 */
149 memblock_reserve(__pa(_text), _end - _text);
150 #ifdef CONFIG_BLK_DEV_INITRD
151 if (initrd_start)
152 memblock_reserve(__virt_to_phys(initrd_start), initrd_end - initrd_start);
153 #endif
154
155 early_init_fdt_scan_reserved_mem();
156
157 /* 4GB maximum for 32-bit only capable devices */
158 if (IS_ENABLED(CONFIG_ZONE_DMA))
159 dma_phys_limit = max_zone_dma_phys();
160
161 high_memory = __va(memblock_end_of_DRAM() - 1) + 1;
162 dma_contiguous_reserve(dma_phys_limit);
163
164 memblock_allow_resize();
165 memblock_dump_all();
166 }
167
bootmem_init(void)168 void __init bootmem_init(void)
169 {
170 unsigned long min, max;
171
172 min = PFN_UP(memblock_start_of_DRAM());
173 max = PFN_DOWN(memblock_end_of_DRAM());
174
175 /*
176 * Sparsemem tries to allocate bootmem in memory_present(), so must be
177 * done after the fixed reservations.
178 */
179 arm64_memory_present();
180
181 sparse_init();
182 zone_sizes_init(min, max);
183
184 max_pfn = max_low_pfn = max;
185 }
186
187 #ifndef CONFIG_SPARSEMEM_VMEMMAP
free_memmap(unsigned long start_pfn,unsigned long end_pfn)188 static inline void free_memmap(unsigned long start_pfn, unsigned long end_pfn)
189 {
190 struct page *start_pg, *end_pg;
191 unsigned long pg, pgend;
192
193 /*
194 * Convert start_pfn/end_pfn to a struct page pointer.
195 */
196 start_pg = pfn_to_page(start_pfn - 1) + 1;
197 end_pg = pfn_to_page(end_pfn - 1) + 1;
198
199 /*
200 * Convert to physical addresses, and round start upwards and end
201 * downwards.
202 */
203 pg = (unsigned long)PAGE_ALIGN(__pa(start_pg));
204 pgend = (unsigned long)__pa(end_pg) & PAGE_MASK;
205
206 /*
207 * If there are free pages between these, free the section of the
208 * memmap array.
209 */
210 if (pg < pgend)
211 free_bootmem(pg, pgend - pg);
212 }
213
214 /*
215 * The mem_map array can get very big. Free the unused area of the memory map.
216 */
free_unused_memmap(void)217 static void __init free_unused_memmap(void)
218 {
219 unsigned long start, prev_end = 0;
220 struct memblock_region *reg;
221
222 for_each_memblock(memory, reg) {
223 start = __phys_to_pfn(reg->base);
224
225 #ifdef CONFIG_SPARSEMEM
226 /*
227 * Take care not to free memmap entries that don't exist due
228 * to SPARSEMEM sections which aren't present.
229 */
230 start = min(start, ALIGN(prev_end, PAGES_PER_SECTION));
231 #endif
232 /*
233 * If we had a previous bank, and there is a space between the
234 * current bank and the previous, free it.
235 */
236 if (prev_end && prev_end < start)
237 free_memmap(prev_end, start);
238
239 /*
240 * Align up here since the VM subsystem insists that the
241 * memmap entries are valid from the bank end aligned to
242 * MAX_ORDER_NR_PAGES.
243 */
244 prev_end = ALIGN(__phys_to_pfn(reg->base + reg->size),
245 MAX_ORDER_NR_PAGES);
246 }
247
248 #ifdef CONFIG_SPARSEMEM
249 if (!IS_ALIGNED(prev_end, PAGES_PER_SECTION))
250 free_memmap(prev_end, ALIGN(prev_end, PAGES_PER_SECTION));
251 #endif
252 }
253 #endif /* !CONFIG_SPARSEMEM_VMEMMAP */
254
255 /*
256 * mem_init() marks the free areas in the mem_map and tells us how much memory
257 * is free. This is done after various parts of the system have claimed their
258 * memory after the kernel image.
259 */
mem_init(void)260 void __init mem_init(void)
261 {
262 set_max_mapnr(pfn_to_page(max_pfn) - mem_map);
263
264 #ifndef CONFIG_SPARSEMEM_VMEMMAP
265 free_unused_memmap();
266 #endif
267 /* this will put all unused low memory onto the freelists */
268 free_all_bootmem();
269
270 mem_init_print_info(NULL);
271
272 #define MLK(b, t) b, t, ((t) - (b)) >> 10
273 #define MLM(b, t) b, t, ((t) - (b)) >> 20
274 #define MLG(b, t) b, t, ((t) - (b)) >> 30
275 #define MLK_ROUNDUP(b, t) b, t, DIV_ROUND_UP(((t) - (b)), SZ_1K)
276
277 pr_notice("Virtual kernel memory layout:\n"
278 " vmalloc : 0x%16lx - 0x%16lx (%6ld GB)\n"
279 #ifdef CONFIG_SPARSEMEM_VMEMMAP
280 " vmemmap : 0x%16lx - 0x%16lx (%6ld GB maximum)\n"
281 " 0x%16lx - 0x%16lx (%6ld MB actual)\n"
282 #endif
283 " PCI I/O : 0x%16lx - 0x%16lx (%6ld MB)\n"
284 " fixed : 0x%16lx - 0x%16lx (%6ld KB)\n"
285 " modules : 0x%16lx - 0x%16lx (%6ld MB)\n"
286 " memory : 0x%16lx - 0x%16lx (%6ld MB)\n"
287 " .init : 0x%p" " - 0x%p" " (%6ld KB)\n"
288 " .text : 0x%p" " - 0x%p" " (%6ld KB)\n"
289 " .data : 0x%p" " - 0x%p" " (%6ld KB)\n",
290 MLG(VMALLOC_START, VMALLOC_END),
291 #ifdef CONFIG_SPARSEMEM_VMEMMAP
292 MLG(VMEMMAP_START,
293 VMEMMAP_START + VMEMMAP_SIZE),
294 MLM((unsigned long)virt_to_page(PAGE_OFFSET),
295 (unsigned long)virt_to_page(high_memory)),
296 #endif
297 MLM((unsigned long)PCI_IOBASE, (unsigned long)PCI_IOBASE + SZ_16M),
298 MLK(FIXADDR_START, FIXADDR_TOP),
299 MLM(MODULES_VADDR, MODULES_END),
300 MLM(PAGE_OFFSET, (unsigned long)high_memory),
301 MLK_ROUNDUP(__init_begin, __init_end),
302 MLK_ROUNDUP(_text, _etext),
303 MLK_ROUNDUP(_sdata, _edata));
304
305 #undef MLK
306 #undef MLM
307 #undef MLK_ROUNDUP
308
309 /*
310 * Check boundaries twice: Some fundamental inconsistencies can be
311 * detected at build time already.
312 */
313 #ifdef CONFIG_COMPAT
314 BUILD_BUG_ON(TASK_SIZE_32 > TASK_SIZE_64);
315 #endif
316 BUILD_BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
317 BUG_ON(TASK_SIZE_64 > MODULES_VADDR);
318
319 if (PAGE_SIZE >= 16384 && get_num_physpages() <= 128) {
320 extern int sysctl_overcommit_memory;
321 /*
322 * On a machine this small we won't get anywhere without
323 * overcommit, so turn it on by default.
324 */
325 sysctl_overcommit_memory = OVERCOMMIT_ALWAYS;
326 }
327 }
328
free_initmem(void)329 void free_initmem(void)
330 {
331 fixup_init();
332 free_initmem_default(0);
333 free_alternatives_memory();
334 }
335
336 #ifdef CONFIG_BLK_DEV_INITRD
337
338 static int keep_initrd;
339
free_initrd_mem(unsigned long start,unsigned long end)340 void free_initrd_mem(unsigned long start, unsigned long end)
341 {
342 if (!keep_initrd)
343 free_reserved_area((void *)start, (void *)end, 0, "initrd");
344 }
345
keepinitrd_setup(char * __unused)346 static int __init keepinitrd_setup(char *__unused)
347 {
348 keep_initrd = 1;
349 return 1;
350 }
351
352 __setup("keepinitrd", keepinitrd_setup);
353 #endif
354