1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012 Regents of the University of California
4 * Copyright (C) 2019 Western Digital Corporation or its affiliates.
5 * Copyright (C) 2020 FORTH-ICS/CARV
6 * Nick Kossifidis <mick@ics.forth.gr>
7 */
8
9 #include <linux/init.h>
10 #include <linux/mm.h>
11 #include <linux/memblock.h>
12 #include <linux/initrd.h>
13 #include <linux/swap.h>
14 #include <linux/swiotlb.h>
15 #include <linux/sizes.h>
16 #include <linux/of_fdt.h>
17 #include <linux/of_reserved_mem.h>
18 #include <linux/libfdt.h>
19 #include <linux/set_memory.h>
20 #include <linux/dma-map-ops.h>
21 #include <linux/crash_dump.h>
22 #include <linux/hugetlb.h>
23 #ifdef CONFIG_RELOCATABLE
24 #include <linux/elf.h>
25 #endif
26 #include <linux/kfence.h>
27
28 #include <asm/fixmap.h>
29 #include <asm/io.h>
30 #include <asm/numa.h>
31 #include <asm/pgtable.h>
32 #include <asm/ptdump.h>
33 #include <asm/sections.h>
34 #include <asm/soc.h>
35 #include <asm/tlbflush.h>
36
37 #include "../kernel/head.h"
38
39 struct kernel_mapping kernel_map __ro_after_init;
40 EXPORT_SYMBOL(kernel_map);
41 #ifdef CONFIG_XIP_KERNEL
42 #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
43 #endif
44
45 #ifdef CONFIG_64BIT
46 u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
47 #else
48 u64 satp_mode __ro_after_init = SATP_MODE_32;
49 #endif
50 EXPORT_SYMBOL(satp_mode);
51
52 bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
53 bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
54 EXPORT_SYMBOL(pgtable_l4_enabled);
55 EXPORT_SYMBOL(pgtable_l5_enabled);
56
57 phys_addr_t phys_ram_base __ro_after_init;
58 EXPORT_SYMBOL(phys_ram_base);
59
60 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
61 __page_aligned_bss;
62 EXPORT_SYMBOL(empty_zero_page);
63
64 extern char _start[];
65 void *_dtb_early_va __initdata;
66 uintptr_t _dtb_early_pa __initdata;
67
68 static phys_addr_t dma32_phys_limit __initdata;
69
zone_sizes_init(void)70 static void __init zone_sizes_init(void)
71 {
72 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
73
74 #ifdef CONFIG_ZONE_DMA32
75 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
76 #endif
77 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
78
79 free_area_init(max_zone_pfns);
80 }
81
82 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
83
84 #define LOG2_SZ_1K ilog2(SZ_1K)
85 #define LOG2_SZ_1M ilog2(SZ_1M)
86 #define LOG2_SZ_1G ilog2(SZ_1G)
87 #define LOG2_SZ_1T ilog2(SZ_1T)
88
print_mlk(char * name,unsigned long b,unsigned long t)89 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
90 {
91 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
92 (((t) - (b)) >> LOG2_SZ_1K));
93 }
94
print_mlm(char * name,unsigned long b,unsigned long t)95 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
96 {
97 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
98 (((t) - (b)) >> LOG2_SZ_1M));
99 }
100
print_mlg(char * name,unsigned long b,unsigned long t)101 static inline void print_mlg(char *name, unsigned long b, unsigned long t)
102 {
103 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t,
104 (((t) - (b)) >> LOG2_SZ_1G));
105 }
106
107 #ifdef CONFIG_64BIT
print_mlt(char * name,unsigned long b,unsigned long t)108 static inline void print_mlt(char *name, unsigned long b, unsigned long t)
109 {
110 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t,
111 (((t) - (b)) >> LOG2_SZ_1T));
112 }
113 #else
114 #define print_mlt(n, b, t) do {} while (0)
115 #endif
116
print_ml(char * name,unsigned long b,unsigned long t)117 static inline void print_ml(char *name, unsigned long b, unsigned long t)
118 {
119 unsigned long diff = t - b;
120
121 if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
122 print_mlt(name, b, t);
123 else if ((diff >> LOG2_SZ_1G) >= 10)
124 print_mlg(name, b, t);
125 else if ((diff >> LOG2_SZ_1M) >= 10)
126 print_mlm(name, b, t);
127 else
128 print_mlk(name, b, t);
129 }
130
print_vm_layout(void)131 static void __init print_vm_layout(void)
132 {
133 pr_notice("Virtual kernel memory layout:\n");
134 print_ml("fixmap", (unsigned long)FIXADDR_START,
135 (unsigned long)FIXADDR_TOP);
136 print_ml("pci io", (unsigned long)PCI_IO_START,
137 (unsigned long)PCI_IO_END);
138 print_ml("vmemmap", (unsigned long)VMEMMAP_START,
139 (unsigned long)VMEMMAP_END);
140 print_ml("vmalloc", (unsigned long)VMALLOC_START,
141 (unsigned long)VMALLOC_END);
142 #ifdef CONFIG_64BIT
143 print_ml("modules", (unsigned long)MODULES_VADDR,
144 (unsigned long)MODULES_END);
145 #endif
146 print_ml("lowmem", (unsigned long)PAGE_OFFSET,
147 (unsigned long)high_memory);
148 if (IS_ENABLED(CONFIG_64BIT)) {
149 #ifdef CONFIG_KASAN
150 print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
151 #endif
152
153 print_ml("kernel", (unsigned long)kernel_map.virt_addr,
154 (unsigned long)ADDRESS_SPACE_END);
155 }
156 }
157 #else
print_vm_layout(void)158 static void print_vm_layout(void) { }
159 #endif /* CONFIG_DEBUG_VM */
160
mem_init(void)161 void __init mem_init(void)
162 {
163 #ifdef CONFIG_FLATMEM
164 BUG_ON(!mem_map);
165 #endif /* CONFIG_FLATMEM */
166
167 swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE);
168 memblock_free_all();
169
170 print_vm_layout();
171 }
172
173 /* Limit the memory size via mem. */
174 static phys_addr_t memory_limit;
175 #ifdef CONFIG_XIP_KERNEL
176 #define memory_limit (*(phys_addr_t *)XIP_FIXUP(&memory_limit))
177 #endif /* CONFIG_XIP_KERNEL */
178
early_mem(char * p)179 static int __init early_mem(char *p)
180 {
181 u64 size;
182
183 if (!p)
184 return 1;
185
186 size = memparse(p, &p) & PAGE_MASK;
187 memory_limit = min_t(u64, size, memory_limit);
188
189 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
190
191 return 0;
192 }
193 early_param("mem", early_mem);
194
setup_bootmem(void)195 static void __init setup_bootmem(void)
196 {
197 phys_addr_t vmlinux_end = __pa_symbol(&_end);
198 phys_addr_t max_mapped_addr;
199 phys_addr_t phys_ram_end, vmlinux_start;
200
201 if (IS_ENABLED(CONFIG_XIP_KERNEL))
202 vmlinux_start = __pa_symbol(&_sdata);
203 else
204 vmlinux_start = __pa_symbol(&_start);
205
206 memblock_enforce_memory_limit(memory_limit);
207
208 /*
209 * Make sure we align the reservation on PMD_SIZE since we will
210 * map the kernel in the linear mapping as read-only: we do not want
211 * any allocation to happen between _end and the next pmd aligned page.
212 */
213 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
214 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
215 /*
216 * Reserve from the start of the kernel to the end of the kernel
217 */
218 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
219
220 phys_ram_end = memblock_end_of_DRAM();
221
222 /*
223 * Make sure we align the start of the memory on a PMD boundary so that
224 * at worst, we map the linear mapping with PMD mappings.
225 */
226 if (!IS_ENABLED(CONFIG_XIP_KERNEL))
227 phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
228
229 /*
230 * In 64-bit, any use of __va/__pa before this point is wrong as we
231 * did not know the start of DRAM before.
232 */
233 if (IS_ENABLED(CONFIG_64BIT))
234 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
235
236 /*
237 * memblock allocator is not aware of the fact that last 4K bytes of
238 * the addressable memory can not be mapped because of IS_ERR_VALUE
239 * macro. Make sure that last 4k bytes are not usable by memblock
240 * if end of dram is equal to maximum addressable memory. For 64-bit
241 * kernel, this problem can't happen here as the end of the virtual
242 * address space is occupied by the kernel mapping then this check must
243 * be done as soon as the kernel mapping base address is determined.
244 */
245 if (!IS_ENABLED(CONFIG_64BIT)) {
246 max_mapped_addr = __pa(~(ulong)0);
247 if (max_mapped_addr == (phys_ram_end - 1))
248 memblock_set_current_limit(max_mapped_addr - 4096);
249 }
250
251 min_low_pfn = PFN_UP(phys_ram_base);
252 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
253 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
254
255 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
256 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
257
258 reserve_initrd_mem();
259
260 /*
261 * No allocation should be done before reserving the memory as defined
262 * in the device tree, otherwise the allocation could end up in a
263 * reserved region.
264 */
265 early_init_fdt_scan_reserved_mem();
266
267 /*
268 * If DTB is built in, no need to reserve its memblock.
269 * Otherwise, do reserve it but avoid using
270 * early_init_fdt_reserve_self() since __pa() does
271 * not work for DTB pointers that are fixmap addresses
272 */
273 if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
274 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
275
276 dma_contiguous_reserve(dma32_phys_limit);
277 if (IS_ENABLED(CONFIG_64BIT))
278 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
279 }
280
281 #ifdef CONFIG_MMU
282 struct pt_alloc_ops pt_ops __initdata;
283
284 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
285 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
286 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
287
288 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
289
290 #ifdef CONFIG_XIP_KERNEL
291 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
292 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
293 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte))
294 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir))
295 #endif /* CONFIG_XIP_KERNEL */
296
297 static const pgprot_t protection_map[16] = {
298 [VM_NONE] = PAGE_NONE,
299 [VM_READ] = PAGE_READ,
300 [VM_WRITE] = PAGE_COPY,
301 [VM_WRITE | VM_READ] = PAGE_COPY,
302 [VM_EXEC] = PAGE_EXEC,
303 [VM_EXEC | VM_READ] = PAGE_READ_EXEC,
304 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC,
305 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC,
306 [VM_SHARED] = PAGE_NONE,
307 [VM_SHARED | VM_READ] = PAGE_READ,
308 [VM_SHARED | VM_WRITE] = PAGE_SHARED,
309 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
310 [VM_SHARED | VM_EXEC] = PAGE_EXEC,
311 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC,
312 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC,
313 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC
314 };
315 DECLARE_VM_GET_PAGE_PROT
316
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t prot)317 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
318 {
319 unsigned long addr = __fix_to_virt(idx);
320 pte_t *ptep;
321
322 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
323
324 ptep = &fixmap_pte[pte_index(addr)];
325
326 if (pgprot_val(prot))
327 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
328 else
329 pte_clear(&init_mm, addr, ptep);
330 local_flush_tlb_page(addr);
331 }
332
get_pte_virt_early(phys_addr_t pa)333 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
334 {
335 return (pte_t *)((uintptr_t)pa);
336 }
337
get_pte_virt_fixmap(phys_addr_t pa)338 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
339 {
340 clear_fixmap(FIX_PTE);
341 return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
342 }
343
get_pte_virt_late(phys_addr_t pa)344 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
345 {
346 return (pte_t *) __va(pa);
347 }
348
alloc_pte_early(uintptr_t va)349 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
350 {
351 /*
352 * We only create PMD or PGD early mappings so we
353 * should never reach here with MMU disabled.
354 */
355 BUG();
356 }
357
alloc_pte_fixmap(uintptr_t va)358 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
359 {
360 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
361 }
362
alloc_pte_late(uintptr_t va)363 static phys_addr_t __init alloc_pte_late(uintptr_t va)
364 {
365 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
366
367 BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
368 return __pa((pte_t *)ptdesc_address(ptdesc));
369 }
370
create_pte_mapping(pte_t * ptep,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)371 static void __init create_pte_mapping(pte_t *ptep,
372 uintptr_t va, phys_addr_t pa,
373 phys_addr_t sz, pgprot_t prot)
374 {
375 uintptr_t pte_idx = pte_index(va);
376
377 BUG_ON(sz != PAGE_SIZE);
378
379 if (pte_none(ptep[pte_idx]))
380 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
381 }
382
383 #ifndef __PAGETABLE_PMD_FOLDED
384
385 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
386 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
387 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
388
389 #ifdef CONFIG_XIP_KERNEL
390 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
391 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd))
392 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
393 #endif /* CONFIG_XIP_KERNEL */
394
395 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
396 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
397 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
398
399 #ifdef CONFIG_XIP_KERNEL
400 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
401 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d))
402 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d))
403 #endif /* CONFIG_XIP_KERNEL */
404
405 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
406 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
407 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
408
409 #ifdef CONFIG_XIP_KERNEL
410 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
411 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud))
412 #define early_pud ((pud_t *)XIP_FIXUP(early_pud))
413 #endif /* CONFIG_XIP_KERNEL */
414
get_pmd_virt_early(phys_addr_t pa)415 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
416 {
417 /* Before MMU is enabled */
418 return (pmd_t *)((uintptr_t)pa);
419 }
420
get_pmd_virt_fixmap(phys_addr_t pa)421 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
422 {
423 clear_fixmap(FIX_PMD);
424 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
425 }
426
get_pmd_virt_late(phys_addr_t pa)427 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
428 {
429 return (pmd_t *) __va(pa);
430 }
431
alloc_pmd_early(uintptr_t va)432 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
433 {
434 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
435
436 return (uintptr_t)early_pmd;
437 }
438
alloc_pmd_fixmap(uintptr_t va)439 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
440 {
441 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
442 }
443
alloc_pmd_late(uintptr_t va)444 static phys_addr_t __init alloc_pmd_late(uintptr_t va)
445 {
446 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
447
448 BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
449 return __pa((pmd_t *)ptdesc_address(ptdesc));
450 }
451
create_pmd_mapping(pmd_t * pmdp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)452 static void __init create_pmd_mapping(pmd_t *pmdp,
453 uintptr_t va, phys_addr_t pa,
454 phys_addr_t sz, pgprot_t prot)
455 {
456 pte_t *ptep;
457 phys_addr_t pte_phys;
458 uintptr_t pmd_idx = pmd_index(va);
459
460 if (sz == PMD_SIZE) {
461 if (pmd_none(pmdp[pmd_idx]))
462 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
463 return;
464 }
465
466 if (pmd_none(pmdp[pmd_idx])) {
467 pte_phys = pt_ops.alloc_pte(va);
468 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
469 ptep = pt_ops.get_pte_virt(pte_phys);
470 memset(ptep, 0, PAGE_SIZE);
471 } else {
472 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
473 ptep = pt_ops.get_pte_virt(pte_phys);
474 }
475
476 create_pte_mapping(ptep, va, pa, sz, prot);
477 }
478
get_pud_virt_early(phys_addr_t pa)479 static pud_t *__init get_pud_virt_early(phys_addr_t pa)
480 {
481 return (pud_t *)((uintptr_t)pa);
482 }
483
get_pud_virt_fixmap(phys_addr_t pa)484 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
485 {
486 clear_fixmap(FIX_PUD);
487 return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
488 }
489
get_pud_virt_late(phys_addr_t pa)490 static pud_t *__init get_pud_virt_late(phys_addr_t pa)
491 {
492 return (pud_t *)__va(pa);
493 }
494
alloc_pud_early(uintptr_t va)495 static phys_addr_t __init alloc_pud_early(uintptr_t va)
496 {
497 /* Only one PUD is available for early mapping */
498 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
499
500 return (uintptr_t)early_pud;
501 }
502
alloc_pud_fixmap(uintptr_t va)503 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
504 {
505 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
506 }
507
alloc_pud_late(uintptr_t va)508 static phys_addr_t alloc_pud_late(uintptr_t va)
509 {
510 unsigned long vaddr;
511
512 vaddr = __get_free_page(GFP_KERNEL);
513 BUG_ON(!vaddr);
514 return __pa(vaddr);
515 }
516
get_p4d_virt_early(phys_addr_t pa)517 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
518 {
519 return (p4d_t *)((uintptr_t)pa);
520 }
521
get_p4d_virt_fixmap(phys_addr_t pa)522 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
523 {
524 clear_fixmap(FIX_P4D);
525 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
526 }
527
get_p4d_virt_late(phys_addr_t pa)528 static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
529 {
530 return (p4d_t *)__va(pa);
531 }
532
alloc_p4d_early(uintptr_t va)533 static phys_addr_t __init alloc_p4d_early(uintptr_t va)
534 {
535 /* Only one P4D is available for early mapping */
536 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
537
538 return (uintptr_t)early_p4d;
539 }
540
alloc_p4d_fixmap(uintptr_t va)541 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
542 {
543 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
544 }
545
alloc_p4d_late(uintptr_t va)546 static phys_addr_t alloc_p4d_late(uintptr_t va)
547 {
548 unsigned long vaddr;
549
550 vaddr = __get_free_page(GFP_KERNEL);
551 BUG_ON(!vaddr);
552 return __pa(vaddr);
553 }
554
create_pud_mapping(pud_t * pudp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)555 static void __init create_pud_mapping(pud_t *pudp,
556 uintptr_t va, phys_addr_t pa,
557 phys_addr_t sz, pgprot_t prot)
558 {
559 pmd_t *nextp;
560 phys_addr_t next_phys;
561 uintptr_t pud_index = pud_index(va);
562
563 if (sz == PUD_SIZE) {
564 if (pud_val(pudp[pud_index]) == 0)
565 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
566 return;
567 }
568
569 if (pud_val(pudp[pud_index]) == 0) {
570 next_phys = pt_ops.alloc_pmd(va);
571 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
572 nextp = pt_ops.get_pmd_virt(next_phys);
573 memset(nextp, 0, PAGE_SIZE);
574 } else {
575 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
576 nextp = pt_ops.get_pmd_virt(next_phys);
577 }
578
579 create_pmd_mapping(nextp, va, pa, sz, prot);
580 }
581
create_p4d_mapping(p4d_t * p4dp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)582 static void __init create_p4d_mapping(p4d_t *p4dp,
583 uintptr_t va, phys_addr_t pa,
584 phys_addr_t sz, pgprot_t prot)
585 {
586 pud_t *nextp;
587 phys_addr_t next_phys;
588 uintptr_t p4d_index = p4d_index(va);
589
590 if (sz == P4D_SIZE) {
591 if (p4d_val(p4dp[p4d_index]) == 0)
592 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
593 return;
594 }
595
596 if (p4d_val(p4dp[p4d_index]) == 0) {
597 next_phys = pt_ops.alloc_pud(va);
598 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
599 nextp = pt_ops.get_pud_virt(next_phys);
600 memset(nextp, 0, PAGE_SIZE);
601 } else {
602 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
603 nextp = pt_ops.get_pud_virt(next_phys);
604 }
605
606 create_pud_mapping(nextp, va, pa, sz, prot);
607 }
608
609 #define pgd_next_t p4d_t
610 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \
611 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \
612 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
613 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \
614 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \
615 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
616 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
617 (pgtable_l5_enabled ? \
618 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
619 (pgtable_l4_enabled ? \
620 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \
621 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
622 #define fixmap_pgd_next (pgtable_l5_enabled ? \
623 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \
624 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
625 #define trampoline_pgd_next (pgtable_l5_enabled ? \
626 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \
627 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
628 #else
629 #define pgd_next_t pte_t
630 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
631 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
632 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
633 create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
634 #define fixmap_pgd_next ((uintptr_t)fixmap_pte)
635 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
636 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
637 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
638 #endif /* __PAGETABLE_PMD_FOLDED */
639
create_pgd_mapping(pgd_t * pgdp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)640 void __init create_pgd_mapping(pgd_t *pgdp,
641 uintptr_t va, phys_addr_t pa,
642 phys_addr_t sz, pgprot_t prot)
643 {
644 pgd_next_t *nextp;
645 phys_addr_t next_phys;
646 uintptr_t pgd_idx = pgd_index(va);
647
648 if (sz == PGDIR_SIZE) {
649 if (pgd_val(pgdp[pgd_idx]) == 0)
650 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
651 return;
652 }
653
654 if (pgd_val(pgdp[pgd_idx]) == 0) {
655 next_phys = alloc_pgd_next(va);
656 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
657 nextp = get_pgd_next_virt(next_phys);
658 memset(nextp, 0, PAGE_SIZE);
659 } else {
660 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
661 nextp = get_pgd_next_virt(next_phys);
662 }
663
664 create_pgd_next_mapping(nextp, va, pa, sz, prot);
665 }
666
best_map_size(phys_addr_t pa,uintptr_t va,phys_addr_t size)667 static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
668 phys_addr_t size)
669 {
670 if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE)
671 return PGDIR_SIZE;
672
673 if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
674 return P4D_SIZE;
675
676 if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
677 return PUD_SIZE;
678
679 if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
680 return PMD_SIZE;
681
682 return PAGE_SIZE;
683 }
684
685 #ifdef CONFIG_XIP_KERNEL
686 #define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
687 extern char _xiprom[], _exiprom[], __data_loc;
688
689 /* called from head.S with MMU off */
__copy_data(void)690 asmlinkage void __init __copy_data(void)
691 {
692 void *from = (void *)(&__data_loc);
693 void *to = (void *)CONFIG_PHYS_RAM_BASE;
694 size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
695
696 memcpy(to, from, sz);
697 }
698 #endif
699
700 #ifdef CONFIG_STRICT_KERNEL_RWX
pgprot_from_va(uintptr_t va)701 static __init pgprot_t pgprot_from_va(uintptr_t va)
702 {
703 if (is_va_kernel_text(va))
704 return PAGE_KERNEL_READ_EXEC;
705
706 /*
707 * In 64-bit kernel, the kernel mapping is outside the linear mapping so
708 * we must protect its linear mapping alias from being executed and
709 * written.
710 * And rodata section is marked readonly in mark_rodata_ro.
711 */
712 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
713 return PAGE_KERNEL_READ;
714
715 return PAGE_KERNEL;
716 }
717
mark_rodata_ro(void)718 void mark_rodata_ro(void)
719 {
720 set_kernel_memory(__start_rodata, _data, set_memory_ro);
721 if (IS_ENABLED(CONFIG_64BIT))
722 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
723 set_memory_ro);
724
725 debug_checkwx();
726 }
727 #else
pgprot_from_va(uintptr_t va)728 static __init pgprot_t pgprot_from_va(uintptr_t va)
729 {
730 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
731 return PAGE_KERNEL;
732
733 return PAGE_KERNEL_EXEC;
734 }
735 #endif /* CONFIG_STRICT_KERNEL_RWX */
736
737 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
738 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
739
disable_pgtable_l5(void)740 static void __init disable_pgtable_l5(void)
741 {
742 pgtable_l5_enabled = false;
743 kernel_map.page_offset = PAGE_OFFSET_L4;
744 satp_mode = SATP_MODE_48;
745 }
746
disable_pgtable_l4(void)747 static void __init disable_pgtable_l4(void)
748 {
749 pgtable_l4_enabled = false;
750 kernel_map.page_offset = PAGE_OFFSET_L3;
751 satp_mode = SATP_MODE_39;
752 }
753
print_no4lvl(char * p)754 static int __init print_no4lvl(char *p)
755 {
756 pr_info("Disabled 4-level and 5-level paging");
757 return 0;
758 }
759 early_param("no4lvl", print_no4lvl);
760
print_no5lvl(char * p)761 static int __init print_no5lvl(char *p)
762 {
763 pr_info("Disabled 5-level paging");
764 return 0;
765 }
766 early_param("no5lvl", print_no5lvl);
767
768 /*
769 * There is a simple way to determine if 4-level is supported by the
770 * underlying hardware: establish 1:1 mapping in 4-level page table mode
771 * then read SATP to see if the configuration was taken into account
772 * meaning sv48 is supported.
773 */
set_satp_mode(uintptr_t dtb_pa)774 static __init void set_satp_mode(uintptr_t dtb_pa)
775 {
776 u64 identity_satp, hw_satp;
777 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
778 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
779
780 if (satp_mode_cmdline == SATP_MODE_57) {
781 disable_pgtable_l5();
782 } else if (satp_mode_cmdline == SATP_MODE_48) {
783 disable_pgtable_l5();
784 disable_pgtable_l4();
785 return;
786 }
787
788 create_p4d_mapping(early_p4d,
789 set_satp_mode_pmd, (uintptr_t)early_pud,
790 P4D_SIZE, PAGE_TABLE);
791 create_pud_mapping(early_pud,
792 set_satp_mode_pmd, (uintptr_t)early_pmd,
793 PUD_SIZE, PAGE_TABLE);
794 /* Handle the case where set_satp_mode straddles 2 PMDs */
795 create_pmd_mapping(early_pmd,
796 set_satp_mode_pmd, set_satp_mode_pmd,
797 PMD_SIZE, PAGE_KERNEL_EXEC);
798 create_pmd_mapping(early_pmd,
799 set_satp_mode_pmd + PMD_SIZE,
800 set_satp_mode_pmd + PMD_SIZE,
801 PMD_SIZE, PAGE_KERNEL_EXEC);
802 retry:
803 create_pgd_mapping(early_pg_dir,
804 set_satp_mode_pmd,
805 pgtable_l5_enabled ?
806 (uintptr_t)early_p4d : (uintptr_t)early_pud,
807 PGDIR_SIZE, PAGE_TABLE);
808
809 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
810
811 local_flush_tlb_all();
812 csr_write(CSR_SATP, identity_satp);
813 hw_satp = csr_swap(CSR_SATP, 0ULL);
814 local_flush_tlb_all();
815
816 if (hw_satp != identity_satp) {
817 if (pgtable_l5_enabled) {
818 disable_pgtable_l5();
819 memset(early_pg_dir, 0, PAGE_SIZE);
820 goto retry;
821 }
822 disable_pgtable_l4();
823 }
824
825 memset(early_pg_dir, 0, PAGE_SIZE);
826 memset(early_p4d, 0, PAGE_SIZE);
827 memset(early_pud, 0, PAGE_SIZE);
828 memset(early_pmd, 0, PAGE_SIZE);
829 }
830 #endif
831
832 /*
833 * setup_vm() is called from head.S with MMU-off.
834 *
835 * Following requirements should be honoured for setup_vm() to work
836 * correctly:
837 * 1) It should use PC-relative addressing for accessing kernel symbols.
838 * To achieve this we always use GCC cmodel=medany.
839 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
840 * so disable compiler instrumentation when FTRACE is enabled.
841 *
842 * Currently, the above requirements are honoured by using custom CFLAGS
843 * for init.o in mm/Makefile.
844 */
845
846 #ifndef __riscv_cmodel_medany
847 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
848 #endif
849
850 #ifdef CONFIG_RELOCATABLE
851 extern unsigned long __rela_dyn_start, __rela_dyn_end;
852
relocate_kernel(void)853 static void __init relocate_kernel(void)
854 {
855 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
856 /*
857 * This holds the offset between the linked virtual address and the
858 * relocated virtual address.
859 */
860 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
861 /*
862 * This holds the offset between kernel linked virtual address and
863 * physical address.
864 */
865 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
866
867 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
868 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
869 Elf64_Addr relocated_addr = rela->r_addend;
870
871 if (rela->r_info != R_RISCV_RELATIVE)
872 continue;
873
874 /*
875 * Make sure to not relocate vdso symbols like rt_sigreturn
876 * which are linked from the address 0 in vmlinux since
877 * vdso symbol addresses are actually used as an offset from
878 * mm->context.vdso in VDSO_OFFSET macro.
879 */
880 if (relocated_addr >= KERNEL_LINK_ADDR)
881 relocated_addr += reloc_offset;
882
883 *(Elf64_Addr *)addr = relocated_addr;
884 }
885 }
886 #endif /* CONFIG_RELOCATABLE */
887
888 #ifdef CONFIG_XIP_KERNEL
create_kernel_page_table(pgd_t * pgdir,__always_unused bool early)889 static void __init create_kernel_page_table(pgd_t *pgdir,
890 __always_unused bool early)
891 {
892 uintptr_t va, end_va;
893
894 /* Map the flash resident part */
895 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
896 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
897 create_pgd_mapping(pgdir, va,
898 kernel_map.xiprom + (va - kernel_map.virt_addr),
899 PMD_SIZE, PAGE_KERNEL_EXEC);
900
901 /* Map the data in RAM */
902 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
903 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
904 create_pgd_mapping(pgdir, va,
905 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
906 PMD_SIZE, PAGE_KERNEL);
907 }
908 #else
create_kernel_page_table(pgd_t * pgdir,bool early)909 static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
910 {
911 uintptr_t va, end_va;
912
913 end_va = kernel_map.virt_addr + kernel_map.size;
914 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
915 create_pgd_mapping(pgdir, va,
916 kernel_map.phys_addr + (va - kernel_map.virt_addr),
917 PMD_SIZE,
918 early ?
919 PAGE_KERNEL_EXEC : pgprot_from_va(va));
920 }
921 #endif
922
923 /*
924 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
925 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
926 * entry.
927 */
create_fdt_early_page_table(uintptr_t fix_fdt_va,uintptr_t dtb_pa)928 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
929 uintptr_t dtb_pa)
930 {
931 #ifndef CONFIG_BUILTIN_DTB
932 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
933
934 /* Make sure the fdt fixmap address is always aligned on PMD size */
935 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
936
937 /* In 32-bit only, the fdt lies in its own PGD */
938 if (!IS_ENABLED(CONFIG_64BIT)) {
939 create_pgd_mapping(early_pg_dir, fix_fdt_va,
940 pa, MAX_FDT_SIZE, PAGE_KERNEL);
941 } else {
942 create_pmd_mapping(fixmap_pmd, fix_fdt_va,
943 pa, PMD_SIZE, PAGE_KERNEL);
944 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
945 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
946 }
947
948 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
949 #else
950 /*
951 * For 64-bit kernel, __va can't be used since it would return a linear
952 * mapping address whereas dtb_early_va will be used before
953 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
954 * kernel is mapped in the linear mapping, that makes no difference.
955 */
956 dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
957 #endif
958
959 dtb_early_pa = dtb_pa;
960 }
961
962 /*
963 * MMU is not enabled, the page tables are allocated directly using
964 * early_pmd/pud/p4d and the address returned is the physical one.
965 */
pt_ops_set_early(void)966 static void __init pt_ops_set_early(void)
967 {
968 pt_ops.alloc_pte = alloc_pte_early;
969 pt_ops.get_pte_virt = get_pte_virt_early;
970 #ifndef __PAGETABLE_PMD_FOLDED
971 pt_ops.alloc_pmd = alloc_pmd_early;
972 pt_ops.get_pmd_virt = get_pmd_virt_early;
973 pt_ops.alloc_pud = alloc_pud_early;
974 pt_ops.get_pud_virt = get_pud_virt_early;
975 pt_ops.alloc_p4d = alloc_p4d_early;
976 pt_ops.get_p4d_virt = get_p4d_virt_early;
977 #endif
978 }
979
980 /*
981 * MMU is enabled but page table setup is not complete yet.
982 * fixmap page table alloc functions must be used as a means to temporarily
983 * map the allocated physical pages since the linear mapping does not exist yet.
984 *
985 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
986 * but it will be used as described above.
987 */
pt_ops_set_fixmap(void)988 static void __init pt_ops_set_fixmap(void)
989 {
990 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
991 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
992 #ifndef __PAGETABLE_PMD_FOLDED
993 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
994 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
995 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
996 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
997 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
998 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
999 #endif
1000 }
1001
1002 /*
1003 * MMU is enabled and page table setup is complete, so from now, we can use
1004 * generic page allocation functions to setup page table.
1005 */
pt_ops_set_late(void)1006 static void __init pt_ops_set_late(void)
1007 {
1008 pt_ops.alloc_pte = alloc_pte_late;
1009 pt_ops.get_pte_virt = get_pte_virt_late;
1010 #ifndef __PAGETABLE_PMD_FOLDED
1011 pt_ops.alloc_pmd = alloc_pmd_late;
1012 pt_ops.get_pmd_virt = get_pmd_virt_late;
1013 pt_ops.alloc_pud = alloc_pud_late;
1014 pt_ops.get_pud_virt = get_pud_virt_late;
1015 pt_ops.alloc_p4d = alloc_p4d_late;
1016 pt_ops.get_p4d_virt = get_p4d_virt_late;
1017 #endif
1018 }
1019
1020 #ifdef CONFIG_RANDOMIZE_BASE
1021 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
1022 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
1023
print_nokaslr(char * p)1024 static int __init print_nokaslr(char *p)
1025 {
1026 pr_info("Disabled KASLR");
1027 return 0;
1028 }
1029 early_param("nokaslr", print_nokaslr);
1030
kaslr_offset(void)1031 unsigned long kaslr_offset(void)
1032 {
1033 return kernel_map.virt_offset;
1034 }
1035 #endif
1036
setup_vm(uintptr_t dtb_pa)1037 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1038 {
1039 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
1040
1041 #ifdef CONFIG_RANDOMIZE_BASE
1042 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
1043 u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
1044 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
1045 u32 nr_pos;
1046
1047 /*
1048 * Compute the number of positions available: we are limited
1049 * by the early page table that only has one PUD and we must
1050 * be aligned on PMD_SIZE.
1051 */
1052 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
1053
1054 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
1055 }
1056 #endif
1057
1058 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
1059
1060 #ifdef CONFIG_XIP_KERNEL
1061 #ifdef CONFIG_64BIT
1062 kernel_map.page_offset = PAGE_OFFSET_L3;
1063 #else
1064 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1065 #endif
1066 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
1067 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
1068
1069 phys_ram_base = CONFIG_PHYS_RAM_BASE;
1070 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
1071 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
1072
1073 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
1074 #else
1075 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1076 kernel_map.phys_addr = (uintptr_t)(&_start);
1077 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
1078 #endif
1079
1080 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
1081 set_satp_mode(dtb_pa);
1082 #endif
1083
1084 /*
1085 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
1086 * where we have the system memory layout: this allows us to align
1087 * the physical and virtual mappings and then make use of PUD/P4D/PGD
1088 * for the linear mapping. This is only possible because the kernel
1089 * mapping lies outside the linear mapping.
1090 * In 32-bit however, as the kernel resides in the linear mapping,
1091 * setup_vm_final can not change the mapping established here,
1092 * otherwise the same kernel addresses would get mapped to different
1093 * physical addresses (if the start of dram is different from the
1094 * kernel physical address start).
1095 */
1096 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
1097 0UL : PAGE_OFFSET - kernel_map.phys_addr;
1098 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
1099
1100 /*
1101 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
1102 * kernel, whereas for 64-bit kernel, the end of the virtual address
1103 * space is occupied by the modules/BPF/kernel mappings which reduces
1104 * the available size of the linear mapping.
1105 */
1106 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
1107
1108 /* Sanity check alignment and size */
1109 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
1110 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
1111
1112 #ifdef CONFIG_64BIT
1113 /*
1114 * The last 4K bytes of the addressable memory can not be mapped because
1115 * of IS_ERR_VALUE macro.
1116 */
1117 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
1118 #endif
1119
1120 #ifdef CONFIG_RELOCATABLE
1121 /*
1122 * Early page table uses only one PUD, which makes it possible
1123 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
1124 * makes the kernel cross over a PUD_SIZE boundary, raise a bug
1125 * since a part of the kernel would not get mapped.
1126 */
1127 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
1128 relocate_kernel();
1129 #endif
1130
1131 apply_early_boot_alternatives();
1132 pt_ops_set_early();
1133
1134 /* Setup early PGD for fixmap */
1135 create_pgd_mapping(early_pg_dir, FIXADDR_START,
1136 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1137
1138 #ifndef __PAGETABLE_PMD_FOLDED
1139 /* Setup fixmap P4D and PUD */
1140 if (pgtable_l5_enabled)
1141 create_p4d_mapping(fixmap_p4d, FIXADDR_START,
1142 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
1143 /* Setup fixmap PUD and PMD */
1144 if (pgtable_l4_enabled)
1145 create_pud_mapping(fixmap_pud, FIXADDR_START,
1146 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
1147 create_pmd_mapping(fixmap_pmd, FIXADDR_START,
1148 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
1149 /* Setup trampoline PGD and PMD */
1150 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1151 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1152 if (pgtable_l5_enabled)
1153 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
1154 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
1155 if (pgtable_l4_enabled)
1156 create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
1157 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
1158 #ifdef CONFIG_XIP_KERNEL
1159 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1160 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
1161 #else
1162 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1163 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
1164 #endif
1165 #else
1166 /* Setup trampoline PGD */
1167 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1168 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
1169 #endif
1170
1171 /*
1172 * Setup early PGD covering entire kernel which will allow
1173 * us to reach paging_init(). We map all memory banks later
1174 * in setup_vm_final() below.
1175 */
1176 create_kernel_page_table(early_pg_dir, true);
1177
1178 /* Setup early mapping for FDT early scan */
1179 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
1180
1181 /*
1182 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
1183 * range can not span multiple pmds.
1184 */
1185 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
1186 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
1187
1188 #ifndef __PAGETABLE_PMD_FOLDED
1189 /*
1190 * Early ioremap fixmap is already created as it lies within first 2MB
1191 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
1192 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
1193 * the user if not.
1194 */
1195 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
1196 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
1197 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
1198 WARN_ON(1);
1199 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
1200 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
1201 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
1202 fix_to_virt(FIX_BTMAP_BEGIN));
1203 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
1204 fix_to_virt(FIX_BTMAP_END));
1205
1206 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
1207 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
1208 }
1209 #endif
1210
1211 pt_ops_set_fixmap();
1212 }
1213
create_linear_mapping_range(phys_addr_t start,phys_addr_t end,uintptr_t fixed_map_size)1214 static void __init create_linear_mapping_range(phys_addr_t start,
1215 phys_addr_t end,
1216 uintptr_t fixed_map_size)
1217 {
1218 phys_addr_t pa;
1219 uintptr_t va, map_size;
1220
1221 for (pa = start; pa < end; pa += map_size) {
1222 va = (uintptr_t)__va(pa);
1223 map_size = fixed_map_size ? fixed_map_size :
1224 best_map_size(pa, va, end - pa);
1225
1226 create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
1227 pgprot_from_va(va));
1228 }
1229 }
1230
create_linear_mapping_page_table(void)1231 static void __init create_linear_mapping_page_table(void)
1232 {
1233 phys_addr_t start, end;
1234 phys_addr_t kfence_pool __maybe_unused;
1235 u64 i;
1236
1237 #ifdef CONFIG_STRICT_KERNEL_RWX
1238 phys_addr_t ktext_start = __pa_symbol(_start);
1239 phys_addr_t ktext_size = __init_data_begin - _start;
1240 phys_addr_t krodata_start = __pa_symbol(__start_rodata);
1241 phys_addr_t krodata_size = _data - __start_rodata;
1242
1243 /* Isolate kernel text and rodata so they don't get mapped with a PUD */
1244 memblock_mark_nomap(ktext_start, ktext_size);
1245 memblock_mark_nomap(krodata_start, krodata_size);
1246 #endif
1247
1248 #ifdef CONFIG_KFENCE
1249 /*
1250 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it
1251 * before we setup the linear mapping so that we avoid using hugepages
1252 * for this region.
1253 */
1254 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
1255 BUG_ON(!kfence_pool);
1256
1257 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
1258 __kfence_pool = __va(kfence_pool);
1259 #endif
1260
1261 /* Map all memory banks in the linear mapping */
1262 for_each_mem_range(i, &start, &end) {
1263 if (start >= end)
1264 break;
1265 if (start <= __pa(PAGE_OFFSET) &&
1266 __pa(PAGE_OFFSET) < end)
1267 start = __pa(PAGE_OFFSET);
1268 if (end >= __pa(PAGE_OFFSET) + memory_limit)
1269 end = __pa(PAGE_OFFSET) + memory_limit;
1270
1271 create_linear_mapping_range(start, end, 0);
1272 }
1273
1274 #ifdef CONFIG_STRICT_KERNEL_RWX
1275 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0);
1276 create_linear_mapping_range(krodata_start,
1277 krodata_start + krodata_size, 0);
1278
1279 memblock_clear_nomap(ktext_start, ktext_size);
1280 memblock_clear_nomap(krodata_start, krodata_size);
1281 #endif
1282
1283 #ifdef CONFIG_KFENCE
1284 create_linear_mapping_range(kfence_pool,
1285 kfence_pool + KFENCE_POOL_SIZE,
1286 PAGE_SIZE);
1287
1288 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
1289 #endif
1290 }
1291
setup_vm_final(void)1292 static void __init setup_vm_final(void)
1293 {
1294 /* Setup swapper PGD for fixmap */
1295 #if !defined(CONFIG_64BIT)
1296 /*
1297 * In 32-bit, the device tree lies in a pgd entry, so it must be copied
1298 * directly in swapper_pg_dir in addition to the pgd entry that points
1299 * to fixmap_pte.
1300 */
1301 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
1302
1303 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
1304 #endif
1305 create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
1306 __pa_symbol(fixmap_pgd_next),
1307 PGDIR_SIZE, PAGE_TABLE);
1308
1309 /* Map the linear mapping */
1310 create_linear_mapping_page_table();
1311
1312 /* Map the kernel */
1313 if (IS_ENABLED(CONFIG_64BIT))
1314 create_kernel_page_table(swapper_pg_dir, false);
1315
1316 #ifdef CONFIG_KASAN
1317 kasan_swapper_init();
1318 #endif
1319
1320 /* Clear fixmap PTE and PMD mappings */
1321 clear_fixmap(FIX_PTE);
1322 clear_fixmap(FIX_PMD);
1323 clear_fixmap(FIX_PUD);
1324 clear_fixmap(FIX_P4D);
1325
1326 /* Move to swapper page table */
1327 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
1328 local_flush_tlb_all();
1329
1330 pt_ops_set_late();
1331 }
1332 #else
setup_vm(uintptr_t dtb_pa)1333 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1334 {
1335 dtb_early_va = (void *)dtb_pa;
1336 dtb_early_pa = dtb_pa;
1337 }
1338
setup_vm_final(void)1339 static inline void setup_vm_final(void)
1340 {
1341 }
1342 #endif /* CONFIG_MMU */
1343
1344 /* Reserve 128M low memory by default for swiotlb buffer */
1345 #define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20)
1346
reserve_crashkernel_low(unsigned long long low_size)1347 static int __init reserve_crashkernel_low(unsigned long long low_size)
1348 {
1349 unsigned long long low_base;
1350
1351 low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);
1352 if (!low_base) {
1353 pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
1354 return -ENOMEM;
1355 }
1356
1357 pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
1358 low_base, low_base + low_size, low_size >> 20);
1359
1360 crashk_low_res.start = low_base;
1361 crashk_low_res.end = low_base + low_size - 1;
1362
1363 return 0;
1364 }
1365
1366 /*
1367 * reserve_crashkernel() - reserves memory for crash kernel
1368 *
1369 * This function reserves memory area given in "crashkernel=" kernel command
1370 * line parameter. The memory reserved is used by dump capture kernel when
1371 * primary kernel is crashing.
1372 */
reserve_crashkernel(void)1373 static void __init reserve_crashkernel(void)
1374 {
1375 unsigned long long crash_base = 0;
1376 unsigned long long crash_size = 0;
1377 unsigned long long crash_low_size = 0;
1378 unsigned long search_start = memblock_start_of_DRAM();
1379 unsigned long search_end = (unsigned long)dma32_phys_limit;
1380 char *cmdline = boot_command_line;
1381 bool fixed_base = false;
1382 bool high = false;
1383
1384 int ret = 0;
1385
1386 if (!IS_ENABLED(CONFIG_KEXEC_CORE))
1387 return;
1388 /*
1389 * Don't reserve a region for a crash kernel on a crash kernel
1390 * since it doesn't make much sense and we have limited memory
1391 * resources.
1392 */
1393 if (is_kdump_kernel()) {
1394 pr_info("crashkernel: ignoring reservation request\n");
1395 return;
1396 }
1397
1398 ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
1399 &crash_size, &crash_base);
1400 if (ret == -ENOENT) {
1401 /* Fallback to crashkernel=X,[high,low] */
1402 ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);
1403 if (ret || !crash_size)
1404 return;
1405
1406 /*
1407 * crashkernel=Y,low is valid only when crashkernel=X,high
1408 * is passed.
1409 */
1410 ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
1411 if (ret == -ENOENT)
1412 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
1413 else if (ret)
1414 return;
1415
1416 search_start = (unsigned long)dma32_phys_limit;
1417 search_end = memblock_end_of_DRAM();
1418 high = true;
1419 } else if (ret || !crash_size) {
1420 /* Invalid argument value specified */
1421 return;
1422 }
1423
1424 crash_size = PAGE_ALIGN(crash_size);
1425
1426 if (crash_base) {
1427 fixed_base = true;
1428 search_start = crash_base;
1429 search_end = crash_base + crash_size;
1430 }
1431
1432 /*
1433 * Current riscv boot protocol requires 2MB alignment for
1434 * RV64 and 4MB alignment for RV32 (hugepage size)
1435 *
1436 * Try to alloc from 32bit addressible physical memory so that
1437 * swiotlb can work on the crash kernel.
1438 */
1439 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
1440 search_start, search_end);
1441 if (crash_base == 0) {
1442 /*
1443 * For crashkernel=size[KMG]@offset[KMG], print out failure
1444 * message if can't reserve the specified region.
1445 */
1446 if (fixed_base) {
1447 pr_warn("crashkernel: allocating failed with given size@offset\n");
1448 return;
1449 }
1450
1451 if (high) {
1452 /*
1453 * For crashkernel=size[KMG],high, if the first attempt was
1454 * for high memory, fall back to low memory.
1455 */
1456 search_start = memblock_start_of_DRAM();
1457 search_end = (unsigned long)dma32_phys_limit;
1458 } else {
1459 /*
1460 * For crashkernel=size[KMG], if the first attempt was for
1461 * low memory, fall back to high memory, the minimum required
1462 * low memory will be reserved later.
1463 */
1464 search_start = (unsigned long)dma32_phys_limit;
1465 search_end = memblock_end_of_DRAM();
1466 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
1467 }
1468
1469 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
1470 search_start, search_end);
1471 if (crash_base == 0) {
1472 pr_warn("crashkernel: couldn't allocate %lldKB\n",
1473 crash_size >> 10);
1474 return;
1475 }
1476 }
1477
1478 if ((crash_base >= dma32_phys_limit) && crash_low_size &&
1479 reserve_crashkernel_low(crash_low_size)) {
1480 memblock_phys_free(crash_base, crash_size);
1481 return;
1482 }
1483
1484 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
1485 crash_base, crash_base + crash_size, crash_size >> 20);
1486
1487 crashk_res.start = crash_base;
1488 crashk_res.end = crash_base + crash_size - 1;
1489 }
1490
paging_init(void)1491 void __init paging_init(void)
1492 {
1493 setup_bootmem();
1494 setup_vm_final();
1495
1496 /* Depend on that Linear Mapping is ready */
1497 memblock_allow_resize();
1498 }
1499
misc_mem_init(void)1500 void __init misc_mem_init(void)
1501 {
1502 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
1503 arch_numa_init();
1504 sparse_init();
1505 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1506 /* The entire VMEMMAP region has been populated. Flush TLB for this region */
1507 local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END);
1508 #endif
1509 zone_sizes_init();
1510 reserve_crashkernel();
1511 memblock_dump_all();
1512 }
1513
1514 #ifdef CONFIG_SPARSEMEM_VMEMMAP
vmemmap_populate(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)1515 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1516 struct vmem_altmap *altmap)
1517 {
1518 return vmemmap_populate_basepages(start, end, node, NULL);
1519 }
1520 #endif
1521
1522 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
1523 /*
1524 * Pre-allocates page-table pages for a specific area in the kernel
1525 * page-table. Only the level which needs to be synchronized between
1526 * all page-tables is allocated because the synchronization can be
1527 * expensive.
1528 */
preallocate_pgd_pages_range(unsigned long start,unsigned long end,const char * area)1529 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end,
1530 const char *area)
1531 {
1532 unsigned long addr;
1533 const char *lvl;
1534
1535 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1536 pgd_t *pgd = pgd_offset_k(addr);
1537 p4d_t *p4d;
1538 pud_t *pud;
1539 pmd_t *pmd;
1540
1541 lvl = "p4d";
1542 p4d = p4d_alloc(&init_mm, pgd, addr);
1543 if (!p4d)
1544 goto failed;
1545
1546 if (pgtable_l5_enabled)
1547 continue;
1548
1549 lvl = "pud";
1550 pud = pud_alloc(&init_mm, p4d, addr);
1551 if (!pud)
1552 goto failed;
1553
1554 if (pgtable_l4_enabled)
1555 continue;
1556
1557 lvl = "pmd";
1558 pmd = pmd_alloc(&init_mm, pud, addr);
1559 if (!pmd)
1560 goto failed;
1561 }
1562 return;
1563
1564 failed:
1565 /*
1566 * The pages have to be there now or they will be missing in
1567 * process page-tables later.
1568 */
1569 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area);
1570 }
1571
pgtable_cache_init(void)1572 void __init pgtable_cache_init(void)
1573 {
1574 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
1575 if (IS_ENABLED(CONFIG_MODULES))
1576 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
1577 }
1578 #endif
1579