xref: /openbmc/linux/arch/riscv/mm/init.c (revision d32fd6bb9f2bc8178cdd65ebec1ad670a8bfa241)
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/sparsemem.h>
36  #include <asm/tlbflush.h>
37  
38  #include "../kernel/head.h"
39  
40  struct kernel_mapping kernel_map __ro_after_init;
41  EXPORT_SYMBOL(kernel_map);
42  #ifdef CONFIG_XIP_KERNEL
43  #define kernel_map	(*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
44  #endif
45  
46  #ifdef CONFIG_64BIT
47  u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
48  #else
49  u64 satp_mode __ro_after_init = SATP_MODE_32;
50  #endif
51  EXPORT_SYMBOL(satp_mode);
52  
53  bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
54  bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
55  EXPORT_SYMBOL(pgtable_l4_enabled);
56  EXPORT_SYMBOL(pgtable_l5_enabled);
57  
58  phys_addr_t phys_ram_base __ro_after_init;
59  EXPORT_SYMBOL(phys_ram_base);
60  
61  #ifdef CONFIG_SPARSEMEM_VMEMMAP
62  #define VMEMMAP_ADDR_ALIGN	(1ULL << SECTION_SIZE_BITS)
63  
64  unsigned long vmemmap_start_pfn __ro_after_init;
65  EXPORT_SYMBOL(vmemmap_start_pfn);
66  #endif
67  
68  unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
69  							__page_aligned_bss;
70  EXPORT_SYMBOL(empty_zero_page);
71  
72  extern char _start[];
73  void *_dtb_early_va __initdata;
74  uintptr_t _dtb_early_pa __initdata;
75  
76  static phys_addr_t dma32_phys_limit __initdata;
77  
zone_sizes_init(void)78  static void __init zone_sizes_init(void)
79  {
80  	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
81  
82  #ifdef CONFIG_ZONE_DMA32
83  	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
84  #endif
85  	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
86  
87  	free_area_init(max_zone_pfns);
88  }
89  
90  #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
91  
92  #define LOG2_SZ_1K  ilog2(SZ_1K)
93  #define LOG2_SZ_1M  ilog2(SZ_1M)
94  #define LOG2_SZ_1G  ilog2(SZ_1G)
95  #define LOG2_SZ_1T  ilog2(SZ_1T)
96  
print_mlk(char * name,unsigned long b,unsigned long t)97  static inline void print_mlk(char *name, unsigned long b, unsigned long t)
98  {
99  	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld kB)\n", name, b, t,
100  		  (((t) - (b)) >> LOG2_SZ_1K));
101  }
102  
print_mlm(char * name,unsigned long b,unsigned long t)103  static inline void print_mlm(char *name, unsigned long b, unsigned long t)
104  {
105  	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld MB)\n", name, b, t,
106  		  (((t) - (b)) >> LOG2_SZ_1M));
107  }
108  
print_mlg(char * name,unsigned long b,unsigned long t)109  static inline void print_mlg(char *name, unsigned long b, unsigned long t)
110  {
111  	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld GB)\n", name, b, t,
112  		   (((t) - (b)) >> LOG2_SZ_1G));
113  }
114  
115  #ifdef CONFIG_64BIT
print_mlt(char * name,unsigned long b,unsigned long t)116  static inline void print_mlt(char *name, unsigned long b, unsigned long t)
117  {
118  	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld TB)\n", name, b, t,
119  		   (((t) - (b)) >> LOG2_SZ_1T));
120  }
121  #else
122  #define print_mlt(n, b, t) do {} while (0)
123  #endif
124  
print_ml(char * name,unsigned long b,unsigned long t)125  static inline void print_ml(char *name, unsigned long b, unsigned long t)
126  {
127  	unsigned long diff = t - b;
128  
129  	if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
130  		print_mlt(name, b, t);
131  	else if ((diff >> LOG2_SZ_1G) >= 10)
132  		print_mlg(name, b, t);
133  	else if ((diff >> LOG2_SZ_1M) >= 10)
134  		print_mlm(name, b, t);
135  	else
136  		print_mlk(name, b, t);
137  }
138  
print_vm_layout(void)139  static void __init print_vm_layout(void)
140  {
141  	pr_notice("Virtual kernel memory layout:\n");
142  	print_ml("fixmap", (unsigned long)FIXADDR_START,
143  		(unsigned long)FIXADDR_TOP);
144  	print_ml("pci io", (unsigned long)PCI_IO_START,
145  		(unsigned long)PCI_IO_END);
146  	print_ml("vmemmap", (unsigned long)VMEMMAP_START,
147  		(unsigned long)VMEMMAP_END);
148  	print_ml("vmalloc", (unsigned long)VMALLOC_START,
149  		(unsigned long)VMALLOC_END);
150  #ifdef CONFIG_64BIT
151  	print_ml("modules", (unsigned long)MODULES_VADDR,
152  		(unsigned long)MODULES_END);
153  #endif
154  	print_ml("lowmem", (unsigned long)PAGE_OFFSET,
155  		(unsigned long)high_memory);
156  	if (IS_ENABLED(CONFIG_64BIT)) {
157  #ifdef CONFIG_KASAN
158  		print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
159  #endif
160  
161  		print_ml("kernel", (unsigned long)kernel_map.virt_addr,
162  			 (unsigned long)ADDRESS_SPACE_END);
163  	}
164  }
165  #else
print_vm_layout(void)166  static void print_vm_layout(void) { }
167  #endif /* CONFIG_DEBUG_VM */
168  
mem_init(void)169  void __init mem_init(void)
170  {
171  #ifdef CONFIG_FLATMEM
172  	BUG_ON(!mem_map);
173  #endif /* CONFIG_FLATMEM */
174  
175  	swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE);
176  	memblock_free_all();
177  
178  	print_vm_layout();
179  }
180  
181  /* Limit the memory size via mem. */
182  static phys_addr_t memory_limit;
183  #ifdef CONFIG_XIP_KERNEL
184  #define memory_limit	(*(phys_addr_t *)XIP_FIXUP(&memory_limit))
185  #endif /* CONFIG_XIP_KERNEL */
186  
early_mem(char * p)187  static int __init early_mem(char *p)
188  {
189  	u64 size;
190  
191  	if (!p)
192  		return 1;
193  
194  	size = memparse(p, &p) & PAGE_MASK;
195  	memory_limit = min_t(u64, size, memory_limit);
196  
197  	pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
198  
199  	return 0;
200  }
201  early_param("mem", early_mem);
202  
setup_bootmem(void)203  static void __init setup_bootmem(void)
204  {
205  	phys_addr_t vmlinux_end = __pa_symbol(&_end);
206  	phys_addr_t max_mapped_addr;
207  	phys_addr_t phys_ram_end, vmlinux_start;
208  
209  	if (IS_ENABLED(CONFIG_XIP_KERNEL))
210  		vmlinux_start = __pa_symbol(&_sdata);
211  	else
212  		vmlinux_start = __pa_symbol(&_start);
213  
214  	memblock_enforce_memory_limit(memory_limit);
215  
216  	/*
217  	 * Make sure we align the reservation on PMD_SIZE since we will
218  	 * map the kernel in the linear mapping as read-only: we do not want
219  	 * any allocation to happen between _end and the next pmd aligned page.
220  	 */
221  	if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
222  		vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
223  	/*
224  	 * Reserve from the start of the kernel to the end of the kernel
225  	 */
226  	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
227  
228  	/*
229  	 * Make sure we align the start of the memory on a PMD boundary so that
230  	 * at worst, we map the linear mapping with PMD mappings.
231  	 */
232  	if (!IS_ENABLED(CONFIG_XIP_KERNEL)) {
233  		phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
234  #ifdef CONFIG_SPARSEMEM_VMEMMAP
235  		vmemmap_start_pfn = round_down(phys_ram_base, VMEMMAP_ADDR_ALIGN) >> PAGE_SHIFT;
236  #endif
237  	}
238  
239  	/*
240  	 * In 64-bit, any use of __va/__pa before this point is wrong as we
241  	 * did not know the start of DRAM before.
242  	 */
243  	if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU))
244  		kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
245  
246  	/*
247  	 * The size of the linear page mapping may restrict the amount of
248  	 * usable RAM.
249  	 */
250  	if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU)) {
251  		max_mapped_addr = __pa(PAGE_OFFSET) + KERN_VIRT_SIZE;
252  		memblock_cap_memory_range(phys_ram_base,
253  					  max_mapped_addr - phys_ram_base);
254  	}
255  
256  	/*
257  	 * Reserve physical address space that would be mapped to virtual
258  	 * addresses greater than (void *)(-PAGE_SIZE) because:
259  	 *  - This memory would overlap with ERR_PTR
260  	 *  - This memory belongs to high memory, which is not supported
261  	 *
262  	 * This is not applicable to 64-bit kernel, because virtual addresses
263  	 * after (void *)(-PAGE_SIZE) are not linearly mapped: they are
264  	 * occupied by kernel mapping. Also it is unrealistic for high memory
265  	 * to exist on 64-bit platforms.
266  	 */
267  	if (!IS_ENABLED(CONFIG_64BIT)) {
268  		max_mapped_addr = __va_to_pa_nodebug(-PAGE_SIZE);
269  		memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr);
270  	}
271  
272  	phys_ram_end = memblock_end_of_DRAM();
273  	min_low_pfn = PFN_UP(phys_ram_base);
274  	max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
275  	high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
276  
277  	dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
278  	set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
279  
280  	reserve_initrd_mem();
281  
282  	/*
283  	 * No allocation should be done before reserving the memory as defined
284  	 * in the device tree, otherwise the allocation could end up in a
285  	 * reserved region.
286  	 */
287  	early_init_fdt_scan_reserved_mem();
288  
289  	/*
290  	 * If DTB is built in, no need to reserve its memblock.
291  	 * Otherwise, do reserve it but avoid using
292  	 * early_init_fdt_reserve_self() since __pa() does
293  	 * not work for DTB pointers that are fixmap addresses
294  	 */
295  	if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
296  		memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
297  
298  	dma_contiguous_reserve(dma32_phys_limit);
299  	if (IS_ENABLED(CONFIG_64BIT))
300  		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
301  }
302  
303  #ifdef CONFIG_MMU
304  struct pt_alloc_ops pt_ops __initdata;
305  
306  pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
307  pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
308  static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
309  
310  pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
311  
312  #ifdef CONFIG_XIP_KERNEL
313  #define pt_ops			(*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
314  #define trampoline_pg_dir      ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
315  #define fixmap_pte             ((pte_t *)XIP_FIXUP(fixmap_pte))
316  #define early_pg_dir           ((pgd_t *)XIP_FIXUP(early_pg_dir))
317  #endif /* CONFIG_XIP_KERNEL */
318  
319  static const pgprot_t protection_map[16] = {
320  	[VM_NONE]					= PAGE_NONE,
321  	[VM_READ]					= PAGE_READ,
322  	[VM_WRITE]					= PAGE_COPY,
323  	[VM_WRITE | VM_READ]				= PAGE_COPY,
324  	[VM_EXEC]					= PAGE_EXEC,
325  	[VM_EXEC | VM_READ]				= PAGE_READ_EXEC,
326  	[VM_EXEC | VM_WRITE]				= PAGE_COPY_EXEC,
327  	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_EXEC,
328  	[VM_SHARED]					= PAGE_NONE,
329  	[VM_SHARED | VM_READ]				= PAGE_READ,
330  	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
331  	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
332  	[VM_SHARED | VM_EXEC]				= PAGE_EXEC,
333  	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READ_EXEC,
334  	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_EXEC,
335  	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_EXEC
336  };
337  DECLARE_VM_GET_PAGE_PROT
338  
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t prot)339  void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
340  {
341  	unsigned long addr = __fix_to_virt(idx);
342  	pte_t *ptep;
343  
344  	BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
345  
346  	ptep = &fixmap_pte[pte_index(addr)];
347  
348  	if (pgprot_val(prot))
349  		set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
350  	else
351  		pte_clear(&init_mm, addr, ptep);
352  	local_flush_tlb_page(addr);
353  }
354  
get_pte_virt_early(phys_addr_t pa)355  static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
356  {
357  	return (pte_t *)((uintptr_t)pa);
358  }
359  
get_pte_virt_fixmap(phys_addr_t pa)360  static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
361  {
362  	clear_fixmap(FIX_PTE);
363  	return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
364  }
365  
get_pte_virt_late(phys_addr_t pa)366  static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
367  {
368  	return (pte_t *) __va(pa);
369  }
370  
alloc_pte_early(uintptr_t va)371  static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
372  {
373  	/*
374  	 * We only create PMD or PGD early mappings so we
375  	 * should never reach here with MMU disabled.
376  	 */
377  	BUG();
378  }
379  
alloc_pte_fixmap(uintptr_t va)380  static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
381  {
382  	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
383  }
384  
alloc_pte_late(uintptr_t va)385  static phys_addr_t __init alloc_pte_late(uintptr_t va)
386  {
387  	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
388  
389  	BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
390  	return __pa((pte_t *)ptdesc_address(ptdesc));
391  }
392  
create_pte_mapping(pte_t * ptep,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)393  static void __init create_pte_mapping(pte_t *ptep,
394  				      uintptr_t va, phys_addr_t pa,
395  				      phys_addr_t sz, pgprot_t prot)
396  {
397  	uintptr_t pte_idx = pte_index(va);
398  
399  	BUG_ON(sz != PAGE_SIZE);
400  
401  	if (pte_none(ptep[pte_idx]))
402  		ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
403  }
404  
405  #ifndef __PAGETABLE_PMD_FOLDED
406  
407  static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
408  static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
409  static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
410  
411  #ifdef CONFIG_XIP_KERNEL
412  #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
413  #define fixmap_pmd     ((pmd_t *)XIP_FIXUP(fixmap_pmd))
414  #define early_pmd      ((pmd_t *)XIP_FIXUP(early_pmd))
415  #endif /* CONFIG_XIP_KERNEL */
416  
417  static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
418  static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
419  static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
420  
421  #ifdef CONFIG_XIP_KERNEL
422  #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
423  #define fixmap_p4d     ((p4d_t *)XIP_FIXUP(fixmap_p4d))
424  #define early_p4d      ((p4d_t *)XIP_FIXUP(early_p4d))
425  #endif /* CONFIG_XIP_KERNEL */
426  
427  static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
428  static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
429  static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
430  
431  #ifdef CONFIG_XIP_KERNEL
432  #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
433  #define fixmap_pud     ((pud_t *)XIP_FIXUP(fixmap_pud))
434  #define early_pud      ((pud_t *)XIP_FIXUP(early_pud))
435  #endif /* CONFIG_XIP_KERNEL */
436  
get_pmd_virt_early(phys_addr_t pa)437  static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
438  {
439  	/* Before MMU is enabled */
440  	return (pmd_t *)((uintptr_t)pa);
441  }
442  
get_pmd_virt_fixmap(phys_addr_t pa)443  static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
444  {
445  	clear_fixmap(FIX_PMD);
446  	return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
447  }
448  
get_pmd_virt_late(phys_addr_t pa)449  static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
450  {
451  	return (pmd_t *) __va(pa);
452  }
453  
alloc_pmd_early(uintptr_t va)454  static phys_addr_t __init alloc_pmd_early(uintptr_t va)
455  {
456  	BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
457  
458  	return (uintptr_t)early_pmd;
459  }
460  
alloc_pmd_fixmap(uintptr_t va)461  static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
462  {
463  	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
464  }
465  
alloc_pmd_late(uintptr_t va)466  static phys_addr_t __init alloc_pmd_late(uintptr_t va)
467  {
468  	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
469  
470  	BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
471  	return __pa((pmd_t *)ptdesc_address(ptdesc));
472  }
473  
create_pmd_mapping(pmd_t * pmdp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)474  static void __init create_pmd_mapping(pmd_t *pmdp,
475  				      uintptr_t va, phys_addr_t pa,
476  				      phys_addr_t sz, pgprot_t prot)
477  {
478  	pte_t *ptep;
479  	phys_addr_t pte_phys;
480  	uintptr_t pmd_idx = pmd_index(va);
481  
482  	if (sz == PMD_SIZE) {
483  		if (pmd_none(pmdp[pmd_idx]))
484  			pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
485  		return;
486  	}
487  
488  	if (pmd_none(pmdp[pmd_idx])) {
489  		pte_phys = pt_ops.alloc_pte(va);
490  		pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
491  		ptep = pt_ops.get_pte_virt(pte_phys);
492  		memset(ptep, 0, PAGE_SIZE);
493  	} else {
494  		pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
495  		ptep = pt_ops.get_pte_virt(pte_phys);
496  	}
497  
498  	create_pte_mapping(ptep, va, pa, sz, prot);
499  }
500  
get_pud_virt_early(phys_addr_t pa)501  static pud_t *__init get_pud_virt_early(phys_addr_t pa)
502  {
503  	return (pud_t *)((uintptr_t)pa);
504  }
505  
get_pud_virt_fixmap(phys_addr_t pa)506  static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
507  {
508  	clear_fixmap(FIX_PUD);
509  	return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
510  }
511  
get_pud_virt_late(phys_addr_t pa)512  static pud_t *__init get_pud_virt_late(phys_addr_t pa)
513  {
514  	return (pud_t *)__va(pa);
515  }
516  
alloc_pud_early(uintptr_t va)517  static phys_addr_t __init alloc_pud_early(uintptr_t va)
518  {
519  	/* Only one PUD is available for early mapping */
520  	BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
521  
522  	return (uintptr_t)early_pud;
523  }
524  
alloc_pud_fixmap(uintptr_t va)525  static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
526  {
527  	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
528  }
529  
alloc_pud_late(uintptr_t va)530  static phys_addr_t alloc_pud_late(uintptr_t va)
531  {
532  	unsigned long vaddr;
533  
534  	vaddr = __get_free_page(GFP_KERNEL);
535  	BUG_ON(!vaddr);
536  	return __pa(vaddr);
537  }
538  
get_p4d_virt_early(phys_addr_t pa)539  static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
540  {
541  	return (p4d_t *)((uintptr_t)pa);
542  }
543  
get_p4d_virt_fixmap(phys_addr_t pa)544  static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
545  {
546  	clear_fixmap(FIX_P4D);
547  	return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
548  }
549  
get_p4d_virt_late(phys_addr_t pa)550  static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
551  {
552  	return (p4d_t *)__va(pa);
553  }
554  
alloc_p4d_early(uintptr_t va)555  static phys_addr_t __init alloc_p4d_early(uintptr_t va)
556  {
557  	/* Only one P4D is available for early mapping */
558  	BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
559  
560  	return (uintptr_t)early_p4d;
561  }
562  
alloc_p4d_fixmap(uintptr_t va)563  static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
564  {
565  	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
566  }
567  
alloc_p4d_late(uintptr_t va)568  static phys_addr_t alloc_p4d_late(uintptr_t va)
569  {
570  	unsigned long vaddr;
571  
572  	vaddr = __get_free_page(GFP_KERNEL);
573  	BUG_ON(!vaddr);
574  	return __pa(vaddr);
575  }
576  
create_pud_mapping(pud_t * pudp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)577  static void __init create_pud_mapping(pud_t *pudp,
578  				      uintptr_t va, phys_addr_t pa,
579  				      phys_addr_t sz, pgprot_t prot)
580  {
581  	pmd_t *nextp;
582  	phys_addr_t next_phys;
583  	uintptr_t pud_index = pud_index(va);
584  
585  	if (sz == PUD_SIZE) {
586  		if (pud_val(pudp[pud_index]) == 0)
587  			pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
588  		return;
589  	}
590  
591  	if (pud_val(pudp[pud_index]) == 0) {
592  		next_phys = pt_ops.alloc_pmd(va);
593  		pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
594  		nextp = pt_ops.get_pmd_virt(next_phys);
595  		memset(nextp, 0, PAGE_SIZE);
596  	} else {
597  		next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
598  		nextp = pt_ops.get_pmd_virt(next_phys);
599  	}
600  
601  	create_pmd_mapping(nextp, va, pa, sz, prot);
602  }
603  
create_p4d_mapping(p4d_t * p4dp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)604  static void __init create_p4d_mapping(p4d_t *p4dp,
605  				      uintptr_t va, phys_addr_t pa,
606  				      phys_addr_t sz, pgprot_t prot)
607  {
608  	pud_t *nextp;
609  	phys_addr_t next_phys;
610  	uintptr_t p4d_index = p4d_index(va);
611  
612  	if (sz == P4D_SIZE) {
613  		if (p4d_val(p4dp[p4d_index]) == 0)
614  			p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
615  		return;
616  	}
617  
618  	if (p4d_val(p4dp[p4d_index]) == 0) {
619  		next_phys = pt_ops.alloc_pud(va);
620  		p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
621  		nextp = pt_ops.get_pud_virt(next_phys);
622  		memset(nextp, 0, PAGE_SIZE);
623  	} else {
624  		next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
625  		nextp = pt_ops.get_pud_virt(next_phys);
626  	}
627  
628  	create_pud_mapping(nextp, va, pa, sz, prot);
629  }
630  
631  #define pgd_next_t		p4d_t
632  #define alloc_pgd_next(__va)	(pgtable_l5_enabled ?			\
633  		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ?		\
634  		pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
635  #define get_pgd_next_virt(__pa)	(pgtable_l5_enabled ?			\
636  		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ?	\
637  		pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
638  #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
639  				(pgtable_l5_enabled ?			\
640  		create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
641  				(pgtable_l4_enabled ?			\
642  		create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) :	\
643  		create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
644  #define fixmap_pgd_next		(pgtable_l5_enabled ?			\
645  		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled ?		\
646  		(uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
647  #define trampoline_pgd_next	(pgtable_l5_enabled ?			\
648  		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled ?	\
649  		(uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
650  #else
651  #define pgd_next_t		pte_t
652  #define alloc_pgd_next(__va)	pt_ops.alloc_pte(__va)
653  #define get_pgd_next_virt(__pa)	pt_ops.get_pte_virt(__pa)
654  #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
655  	create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
656  #define fixmap_pgd_next		((uintptr_t)fixmap_pte)
657  #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
658  #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
659  #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
660  #endif /* __PAGETABLE_PMD_FOLDED */
661  
create_pgd_mapping(pgd_t * pgdp,uintptr_t va,phys_addr_t pa,phys_addr_t sz,pgprot_t prot)662  void __init create_pgd_mapping(pgd_t *pgdp,
663  				      uintptr_t va, phys_addr_t pa,
664  				      phys_addr_t sz, pgprot_t prot)
665  {
666  	pgd_next_t *nextp;
667  	phys_addr_t next_phys;
668  	uintptr_t pgd_idx = pgd_index(va);
669  
670  	if (sz == PGDIR_SIZE) {
671  		if (pgd_val(pgdp[pgd_idx]) == 0)
672  			pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
673  		return;
674  	}
675  
676  	if (pgd_val(pgdp[pgd_idx]) == 0) {
677  		next_phys = alloc_pgd_next(va);
678  		pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
679  		nextp = get_pgd_next_virt(next_phys);
680  		memset(nextp, 0, PAGE_SIZE);
681  	} else {
682  		next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
683  		nextp = get_pgd_next_virt(next_phys);
684  	}
685  
686  	create_pgd_next_mapping(nextp, va, pa, sz, prot);
687  }
688  
best_map_size(phys_addr_t pa,uintptr_t va,phys_addr_t size)689  static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
690  				      phys_addr_t size)
691  {
692  	if (debug_pagealloc_enabled())
693  		return PAGE_SIZE;
694  
695  	if (pgtable_l5_enabled &&
696  	    !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
697  		return P4D_SIZE;
698  
699  	if (pgtable_l4_enabled &&
700  	    !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
701  		return PUD_SIZE;
702  
703  	if (IS_ENABLED(CONFIG_64BIT) &&
704  	    !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
705  		return PMD_SIZE;
706  
707  	return PAGE_SIZE;
708  }
709  
710  #ifdef CONFIG_XIP_KERNEL
711  #define phys_ram_base  (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
712  extern char _xiprom[], _exiprom[], __data_loc;
713  
714  /* called from head.S with MMU off */
__copy_data(void)715  asmlinkage void __init __copy_data(void)
716  {
717  	void *from = (void *)(&__data_loc);
718  	void *to = (void *)CONFIG_PHYS_RAM_BASE;
719  	size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
720  
721  	memcpy(to, from, sz);
722  }
723  #endif
724  
725  #ifdef CONFIG_STRICT_KERNEL_RWX
pgprot_from_va(uintptr_t va)726  static __init pgprot_t pgprot_from_va(uintptr_t va)
727  {
728  	if (is_va_kernel_text(va))
729  		return PAGE_KERNEL_READ_EXEC;
730  
731  	/*
732  	 * In 64-bit kernel, the kernel mapping is outside the linear mapping so
733  	 * we must protect its linear mapping alias from being executed and
734  	 * written.
735  	 * And rodata section is marked readonly in mark_rodata_ro.
736  	 */
737  	if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
738  		return PAGE_KERNEL_READ;
739  
740  	return PAGE_KERNEL;
741  }
742  
mark_rodata_ro(void)743  void mark_rodata_ro(void)
744  {
745  	set_kernel_memory(__start_rodata, _data, set_memory_ro);
746  	if (IS_ENABLED(CONFIG_64BIT))
747  		set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
748  				  set_memory_ro);
749  
750  	debug_checkwx();
751  }
752  #else
pgprot_from_va(uintptr_t va)753  static __init pgprot_t pgprot_from_va(uintptr_t va)
754  {
755  	if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
756  		return PAGE_KERNEL;
757  
758  	return PAGE_KERNEL_EXEC;
759  }
760  #endif /* CONFIG_STRICT_KERNEL_RWX */
761  
762  #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
763  u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
764  
disable_pgtable_l5(void)765  static void __init disable_pgtable_l5(void)
766  {
767  	pgtable_l5_enabled = false;
768  	kernel_map.page_offset = PAGE_OFFSET_L4;
769  	satp_mode = SATP_MODE_48;
770  }
771  
disable_pgtable_l4(void)772  static void __init disable_pgtable_l4(void)
773  {
774  	pgtable_l4_enabled = false;
775  	kernel_map.page_offset = PAGE_OFFSET_L3;
776  	satp_mode = SATP_MODE_39;
777  }
778  
print_no4lvl(char * p)779  static int __init print_no4lvl(char *p)
780  {
781  	pr_info("Disabled 4-level and 5-level paging");
782  	return 0;
783  }
784  early_param("no4lvl", print_no4lvl);
785  
print_no5lvl(char * p)786  static int __init print_no5lvl(char *p)
787  {
788  	pr_info("Disabled 5-level paging");
789  	return 0;
790  }
791  early_param("no5lvl", print_no5lvl);
792  
793  /*
794   * There is a simple way to determine if 4-level is supported by the
795   * underlying hardware: establish 1:1 mapping in 4-level page table mode
796   * then read SATP to see if the configuration was taken into account
797   * meaning sv48 is supported.
798   */
set_satp_mode(uintptr_t dtb_pa)799  static __init void set_satp_mode(uintptr_t dtb_pa)
800  {
801  	u64 identity_satp, hw_satp;
802  	uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
803  	u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
804  
805  	if (satp_mode_cmdline == SATP_MODE_57) {
806  		disable_pgtable_l5();
807  	} else if (satp_mode_cmdline == SATP_MODE_48) {
808  		disable_pgtable_l5();
809  		disable_pgtable_l4();
810  		return;
811  	}
812  
813  	create_p4d_mapping(early_p4d,
814  			set_satp_mode_pmd, (uintptr_t)early_pud,
815  			P4D_SIZE, PAGE_TABLE);
816  	create_pud_mapping(early_pud,
817  			   set_satp_mode_pmd, (uintptr_t)early_pmd,
818  			   PUD_SIZE, PAGE_TABLE);
819  	/* Handle the case where set_satp_mode straddles 2 PMDs */
820  	create_pmd_mapping(early_pmd,
821  			   set_satp_mode_pmd, set_satp_mode_pmd,
822  			   PMD_SIZE, PAGE_KERNEL_EXEC);
823  	create_pmd_mapping(early_pmd,
824  			   set_satp_mode_pmd + PMD_SIZE,
825  			   set_satp_mode_pmd + PMD_SIZE,
826  			   PMD_SIZE, PAGE_KERNEL_EXEC);
827  retry:
828  	create_pgd_mapping(early_pg_dir,
829  			   set_satp_mode_pmd,
830  			   pgtable_l5_enabled ?
831  				(uintptr_t)early_p4d : (uintptr_t)early_pud,
832  			   PGDIR_SIZE, PAGE_TABLE);
833  
834  	identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
835  
836  	local_flush_tlb_all();
837  	csr_write(CSR_SATP, identity_satp);
838  	hw_satp = csr_swap(CSR_SATP, 0ULL);
839  	local_flush_tlb_all();
840  
841  	if (hw_satp != identity_satp) {
842  		if (pgtable_l5_enabled) {
843  			disable_pgtable_l5();
844  			memset(early_pg_dir, 0, PAGE_SIZE);
845  			goto retry;
846  		}
847  		disable_pgtable_l4();
848  	}
849  
850  	memset(early_pg_dir, 0, PAGE_SIZE);
851  	memset(early_p4d, 0, PAGE_SIZE);
852  	memset(early_pud, 0, PAGE_SIZE);
853  	memset(early_pmd, 0, PAGE_SIZE);
854  }
855  #endif
856  
857  /*
858   * setup_vm() is called from head.S with MMU-off.
859   *
860   * Following requirements should be honoured for setup_vm() to work
861   * correctly:
862   * 1) It should use PC-relative addressing for accessing kernel symbols.
863   *    To achieve this we always use GCC cmodel=medany.
864   * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
865   *    so disable compiler instrumentation when FTRACE is enabled.
866   *
867   * Currently, the above requirements are honoured by using custom CFLAGS
868   * for init.o in mm/Makefile.
869   */
870  
871  #ifndef __riscv_cmodel_medany
872  #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
873  #endif
874  
875  #ifdef CONFIG_RELOCATABLE
876  extern unsigned long __rela_dyn_start, __rela_dyn_end;
877  
relocate_kernel(void)878  static void __init relocate_kernel(void)
879  {
880  	Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
881  	/*
882  	 * This holds the offset between the linked virtual address and the
883  	 * relocated virtual address.
884  	 */
885  	uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
886  	/*
887  	 * This holds the offset between kernel linked virtual address and
888  	 * physical address.
889  	 */
890  	uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
891  
892  	for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
893  		Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
894  		Elf64_Addr relocated_addr = rela->r_addend;
895  
896  		if (rela->r_info != R_RISCV_RELATIVE)
897  			continue;
898  
899  		/*
900  		 * Make sure to not relocate vdso symbols like rt_sigreturn
901  		 * which are linked from the address 0 in vmlinux since
902  		 * vdso symbol addresses are actually used as an offset from
903  		 * mm->context.vdso in VDSO_OFFSET macro.
904  		 */
905  		if (relocated_addr >= KERNEL_LINK_ADDR)
906  			relocated_addr += reloc_offset;
907  
908  		*(Elf64_Addr *)addr = relocated_addr;
909  	}
910  }
911  #endif /* CONFIG_RELOCATABLE */
912  
913  #ifdef CONFIG_XIP_KERNEL
create_kernel_page_table(pgd_t * pgdir,__always_unused bool early)914  static void __init create_kernel_page_table(pgd_t *pgdir,
915  					    __always_unused bool early)
916  {
917  	uintptr_t va, end_va;
918  
919  	/* Map the flash resident part */
920  	end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
921  	for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
922  		create_pgd_mapping(pgdir, va,
923  				   kernel_map.xiprom + (va - kernel_map.virt_addr),
924  				   PMD_SIZE, PAGE_KERNEL_EXEC);
925  
926  	/* Map the data in RAM */
927  	end_va = kernel_map.virt_addr + kernel_map.size;
928  	for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
929  		create_pgd_mapping(pgdir, va,
930  				   kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
931  				   PMD_SIZE, PAGE_KERNEL);
932  }
933  #else
create_kernel_page_table(pgd_t * pgdir,bool early)934  static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
935  {
936  	uintptr_t va, end_va;
937  
938  	end_va = kernel_map.virt_addr + kernel_map.size;
939  	for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
940  		create_pgd_mapping(pgdir, va,
941  				   kernel_map.phys_addr + (va - kernel_map.virt_addr),
942  				   PMD_SIZE,
943  				   early ?
944  					PAGE_KERNEL_EXEC : pgprot_from_va(va));
945  }
946  #endif
947  
948  /*
949   * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
950   * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
951   * entry.
952   */
create_fdt_early_page_table(uintptr_t fix_fdt_va,uintptr_t dtb_pa)953  static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
954  					       uintptr_t dtb_pa)
955  {
956  #ifndef CONFIG_BUILTIN_DTB
957  	uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
958  
959  	/* Make sure the fdt fixmap address is always aligned on PMD size */
960  	BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
961  
962  	/* In 32-bit only, the fdt lies in its own PGD */
963  	if (!IS_ENABLED(CONFIG_64BIT)) {
964  		create_pgd_mapping(early_pg_dir, fix_fdt_va,
965  				   pa, MAX_FDT_SIZE, PAGE_KERNEL);
966  	} else {
967  		create_pmd_mapping(fixmap_pmd, fix_fdt_va,
968  				   pa, PMD_SIZE, PAGE_KERNEL);
969  		create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
970  				   pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
971  	}
972  
973  	dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
974  #else
975  	/*
976  	 * For 64-bit kernel, __va can't be used since it would return a linear
977  	 * mapping address whereas dtb_early_va will be used before
978  	 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
979  	 * kernel is mapped in the linear mapping, that makes no difference.
980  	 */
981  	dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
982  #endif
983  
984  	dtb_early_pa = dtb_pa;
985  }
986  
987  /*
988   * MMU is not enabled, the page tables are allocated directly using
989   * early_pmd/pud/p4d and the address returned is the physical one.
990   */
pt_ops_set_early(void)991  static void __init pt_ops_set_early(void)
992  {
993  	pt_ops.alloc_pte = alloc_pte_early;
994  	pt_ops.get_pte_virt = get_pte_virt_early;
995  #ifndef __PAGETABLE_PMD_FOLDED
996  	pt_ops.alloc_pmd = alloc_pmd_early;
997  	pt_ops.get_pmd_virt = get_pmd_virt_early;
998  	pt_ops.alloc_pud = alloc_pud_early;
999  	pt_ops.get_pud_virt = get_pud_virt_early;
1000  	pt_ops.alloc_p4d = alloc_p4d_early;
1001  	pt_ops.get_p4d_virt = get_p4d_virt_early;
1002  #endif
1003  }
1004  
1005  /*
1006   * MMU is enabled but page table setup is not complete yet.
1007   * fixmap page table alloc functions must be used as a means to temporarily
1008   * map the allocated physical pages since the linear mapping does not exist yet.
1009   *
1010   * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
1011   * but it will be used as described above.
1012   */
pt_ops_set_fixmap(void)1013  static void __init pt_ops_set_fixmap(void)
1014  {
1015  	pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
1016  	pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
1017  #ifndef __PAGETABLE_PMD_FOLDED
1018  	pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
1019  	pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
1020  	pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
1021  	pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
1022  	pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
1023  	pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
1024  #endif
1025  }
1026  
1027  /*
1028   * MMU is enabled and page table setup is complete, so from now, we can use
1029   * generic page allocation functions to setup page table.
1030   */
pt_ops_set_late(void)1031  static void __init pt_ops_set_late(void)
1032  {
1033  	pt_ops.alloc_pte = alloc_pte_late;
1034  	pt_ops.get_pte_virt = get_pte_virt_late;
1035  #ifndef __PAGETABLE_PMD_FOLDED
1036  	pt_ops.alloc_pmd = alloc_pmd_late;
1037  	pt_ops.get_pmd_virt = get_pmd_virt_late;
1038  	pt_ops.alloc_pud = alloc_pud_late;
1039  	pt_ops.get_pud_virt = get_pud_virt_late;
1040  	pt_ops.alloc_p4d = alloc_p4d_late;
1041  	pt_ops.get_p4d_virt = get_p4d_virt_late;
1042  #endif
1043  }
1044  
1045  #ifdef CONFIG_RANDOMIZE_BASE
1046  extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
1047  extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
1048  
print_nokaslr(char * p)1049  static int __init print_nokaslr(char *p)
1050  {
1051  	pr_info("Disabled KASLR");
1052  	return 0;
1053  }
1054  early_param("nokaslr", print_nokaslr);
1055  
kaslr_offset(void)1056  unsigned long kaslr_offset(void)
1057  {
1058  	return kernel_map.virt_offset;
1059  }
1060  #endif
1061  
setup_vm(uintptr_t dtb_pa)1062  asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1063  {
1064  	pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
1065  
1066  #ifdef CONFIG_RANDOMIZE_BASE
1067  	if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
1068  		u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
1069  		u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
1070  		u32 nr_pos;
1071  
1072  		/*
1073  		 * Compute the number of positions available: we are limited
1074  		 * by the early page table that only has one PUD and we must
1075  		 * be aligned on PMD_SIZE.
1076  		 */
1077  		nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
1078  
1079  		kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
1080  	}
1081  #endif
1082  
1083  	kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
1084  
1085  #ifdef CONFIG_XIP_KERNEL
1086  #ifdef CONFIG_64BIT
1087  	kernel_map.page_offset = PAGE_OFFSET_L3;
1088  #else
1089  	kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1090  #endif
1091  	kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
1092  	kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
1093  
1094  	phys_ram_base = CONFIG_PHYS_RAM_BASE;
1095  #ifdef CONFIG_SPARSEMEM_VMEMMAP
1096  	vmemmap_start_pfn = round_down(phys_ram_base, VMEMMAP_ADDR_ALIGN) >> PAGE_SHIFT;
1097  #endif
1098  	kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
1099  	kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
1100  
1101  	kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
1102  #else
1103  	kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1104  	kernel_map.phys_addr = (uintptr_t)(&_start);
1105  	kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
1106  #endif
1107  
1108  #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
1109  	set_satp_mode(dtb_pa);
1110  #endif
1111  
1112  	/*
1113  	 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
1114  	 * where we have the system memory layout: this allows us to align
1115  	 * the physical and virtual mappings and then make use of PUD/P4D/PGD
1116  	 * for the linear mapping. This is only possible because the kernel
1117  	 * mapping lies outside the linear mapping.
1118  	 * In 32-bit however, as the kernel resides in the linear mapping,
1119  	 * setup_vm_final can not change the mapping established here,
1120  	 * otherwise the same kernel addresses would get mapped to different
1121  	 * physical addresses (if the start of dram is different from the
1122  	 * kernel physical address start).
1123  	 */
1124  	kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
1125  				0UL : PAGE_OFFSET - kernel_map.phys_addr;
1126  	kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
1127  
1128  	/*
1129  	 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
1130  	 * kernel, whereas for 64-bit kernel, the end of the virtual address
1131  	 * space is occupied by the modules/BPF/kernel mappings which reduces
1132  	 * the available size of the linear mapping.
1133  	 */
1134  	memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
1135  
1136  	/* Sanity check alignment and size */
1137  	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
1138  	BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
1139  
1140  #ifdef CONFIG_64BIT
1141  	/*
1142  	 * The last 4K bytes of the addressable memory can not be mapped because
1143  	 * of IS_ERR_VALUE macro.
1144  	 */
1145  	BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
1146  #endif
1147  
1148  #ifdef CONFIG_RELOCATABLE
1149  	/*
1150  	 * Early page table uses only one PUD, which makes it possible
1151  	 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
1152  	 * makes the kernel cross over a PUD_SIZE boundary, raise a bug
1153  	 * since a part of the kernel would not get mapped.
1154  	 */
1155  	BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
1156  	relocate_kernel();
1157  #endif
1158  
1159  	apply_early_boot_alternatives();
1160  	pt_ops_set_early();
1161  
1162  	/* Setup early PGD for fixmap */
1163  	create_pgd_mapping(early_pg_dir, FIXADDR_START,
1164  			   fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1165  
1166  #ifndef __PAGETABLE_PMD_FOLDED
1167  	/* Setup fixmap P4D and PUD */
1168  	if (pgtable_l5_enabled)
1169  		create_p4d_mapping(fixmap_p4d, FIXADDR_START,
1170  				   (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
1171  	/* Setup fixmap PUD and PMD */
1172  	if (pgtable_l4_enabled)
1173  		create_pud_mapping(fixmap_pud, FIXADDR_START,
1174  				   (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
1175  	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
1176  			   (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
1177  	/* Setup trampoline PGD and PMD */
1178  	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1179  			   trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1180  	if (pgtable_l5_enabled)
1181  		create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
1182  				   (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
1183  	if (pgtable_l4_enabled)
1184  		create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
1185  				   (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
1186  #ifdef CONFIG_XIP_KERNEL
1187  	create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1188  			   kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
1189  #else
1190  	create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1191  			   kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
1192  #endif
1193  #else
1194  	/* Setup trampoline PGD */
1195  	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1196  			   kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
1197  #endif
1198  
1199  	/*
1200  	 * Setup early PGD covering entire kernel which will allow
1201  	 * us to reach paging_init(). We map all memory banks later
1202  	 * in setup_vm_final() below.
1203  	 */
1204  	create_kernel_page_table(early_pg_dir, true);
1205  
1206  	/* Setup early mapping for FDT early scan */
1207  	create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
1208  
1209  	/*
1210  	 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
1211  	 * range can not span multiple pmds.
1212  	 */
1213  	BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
1214  		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
1215  
1216  #ifndef __PAGETABLE_PMD_FOLDED
1217  	/*
1218  	 * Early ioremap fixmap is already created as it lies within first 2MB
1219  	 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
1220  	 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
1221  	 * the user if not.
1222  	 */
1223  	fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
1224  	fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
1225  	if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
1226  		WARN_ON(1);
1227  		pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
1228  			pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
1229  		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
1230  			fix_to_virt(FIX_BTMAP_BEGIN));
1231  		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
1232  			fix_to_virt(FIX_BTMAP_END));
1233  
1234  		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
1235  		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
1236  	}
1237  #endif
1238  
1239  	pt_ops_set_fixmap();
1240  }
1241  
create_linear_mapping_range(phys_addr_t start,phys_addr_t end,uintptr_t fixed_map_size)1242  static void __init create_linear_mapping_range(phys_addr_t start,
1243  					       phys_addr_t end,
1244  					       uintptr_t fixed_map_size)
1245  {
1246  	phys_addr_t pa;
1247  	uintptr_t va, map_size;
1248  
1249  	for (pa = start; pa < end; pa += map_size) {
1250  		va = (uintptr_t)__va(pa);
1251  		map_size = fixed_map_size ? fixed_map_size :
1252  					    best_map_size(pa, va, end - pa);
1253  
1254  		create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
1255  				   pgprot_from_va(va));
1256  	}
1257  }
1258  
create_linear_mapping_page_table(void)1259  static void __init create_linear_mapping_page_table(void)
1260  {
1261  	phys_addr_t start, end;
1262  	phys_addr_t kfence_pool __maybe_unused;
1263  	u64 i;
1264  
1265  #ifdef CONFIG_STRICT_KERNEL_RWX
1266  	phys_addr_t ktext_start = __pa_symbol(_start);
1267  	phys_addr_t ktext_size = __init_data_begin - _start;
1268  	phys_addr_t krodata_start = __pa_symbol(__start_rodata);
1269  	phys_addr_t krodata_size = _data - __start_rodata;
1270  
1271  	/* Isolate kernel text and rodata so they don't get mapped with a PUD */
1272  	memblock_mark_nomap(ktext_start,  ktext_size);
1273  	memblock_mark_nomap(krodata_start, krodata_size);
1274  #endif
1275  
1276  #ifdef CONFIG_KFENCE
1277  	/*
1278  	 *  kfence pool must be backed by PAGE_SIZE mappings, so allocate it
1279  	 *  before we setup the linear mapping so that we avoid using hugepages
1280  	 *  for this region.
1281  	 */
1282  	kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
1283  	BUG_ON(!kfence_pool);
1284  
1285  	memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
1286  	__kfence_pool = __va(kfence_pool);
1287  #endif
1288  
1289  	/* Map all memory banks in the linear mapping */
1290  	for_each_mem_range(i, &start, &end) {
1291  		if (start >= end)
1292  			break;
1293  		if (start <= __pa(PAGE_OFFSET) &&
1294  		    __pa(PAGE_OFFSET) < end)
1295  			start = __pa(PAGE_OFFSET);
1296  
1297  		create_linear_mapping_range(start, end, 0);
1298  	}
1299  
1300  #ifdef CONFIG_STRICT_KERNEL_RWX
1301  	create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0);
1302  	create_linear_mapping_range(krodata_start,
1303  				    krodata_start + krodata_size, 0);
1304  
1305  	memblock_clear_nomap(ktext_start,  ktext_size);
1306  	memblock_clear_nomap(krodata_start, krodata_size);
1307  #endif
1308  
1309  #ifdef CONFIG_KFENCE
1310  	create_linear_mapping_range(kfence_pool,
1311  				    kfence_pool + KFENCE_POOL_SIZE,
1312  				    PAGE_SIZE);
1313  
1314  	memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
1315  #endif
1316  }
1317  
setup_vm_final(void)1318  static void __init setup_vm_final(void)
1319  {
1320  	/* Setup swapper PGD for fixmap */
1321  #if !defined(CONFIG_64BIT)
1322  	/*
1323  	 * In 32-bit, the device tree lies in a pgd entry, so it must be copied
1324  	 * directly in swapper_pg_dir in addition to the pgd entry that points
1325  	 * to fixmap_pte.
1326  	 */
1327  	unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
1328  
1329  	set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
1330  #endif
1331  	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
1332  			   __pa_symbol(fixmap_pgd_next),
1333  			   PGDIR_SIZE, PAGE_TABLE);
1334  
1335  	/* Map the linear mapping */
1336  	create_linear_mapping_page_table();
1337  
1338  	/* Map the kernel */
1339  	if (IS_ENABLED(CONFIG_64BIT))
1340  		create_kernel_page_table(swapper_pg_dir, false);
1341  
1342  #ifdef CONFIG_KASAN
1343  	kasan_swapper_init();
1344  #endif
1345  
1346  	/* Clear fixmap PTE and PMD mappings */
1347  	clear_fixmap(FIX_PTE);
1348  	clear_fixmap(FIX_PMD);
1349  	clear_fixmap(FIX_PUD);
1350  	clear_fixmap(FIX_P4D);
1351  
1352  	/* Move to swapper page table */
1353  	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
1354  	local_flush_tlb_all();
1355  
1356  	pt_ops_set_late();
1357  }
1358  #else
setup_vm(uintptr_t dtb_pa)1359  asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1360  {
1361  	dtb_early_va = (void *)dtb_pa;
1362  	dtb_early_pa = dtb_pa;
1363  }
1364  
setup_vm_final(void)1365  static inline void setup_vm_final(void)
1366  {
1367  }
1368  #endif /* CONFIG_MMU */
1369  
1370  /* Reserve 128M low memory by default for swiotlb buffer */
1371  #define DEFAULT_CRASH_KERNEL_LOW_SIZE	(128UL << 20)
1372  
reserve_crashkernel_low(unsigned long long low_size)1373  static int __init reserve_crashkernel_low(unsigned long long low_size)
1374  {
1375  	unsigned long long low_base;
1376  
1377  	low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);
1378  	if (!low_base) {
1379  		pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);
1380  		return -ENOMEM;
1381  	}
1382  
1383  	pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",
1384  		low_base, low_base + low_size, low_size >> 20);
1385  
1386  	crashk_low_res.start = low_base;
1387  	crashk_low_res.end = low_base + low_size - 1;
1388  
1389  	return 0;
1390  }
1391  
1392  /*
1393   * reserve_crashkernel() - reserves memory for crash kernel
1394   *
1395   * This function reserves memory area given in "crashkernel=" kernel command
1396   * line parameter. The memory reserved is used by dump capture kernel when
1397   * primary kernel is crashing.
1398   */
reserve_crashkernel(void)1399  static void __init reserve_crashkernel(void)
1400  {
1401  	unsigned long long crash_base = 0;
1402  	unsigned long long crash_size = 0;
1403  	unsigned long long crash_low_size = 0;
1404  	unsigned long search_start = memblock_start_of_DRAM();
1405  	unsigned long search_end = (unsigned long)dma32_phys_limit;
1406  	char *cmdline = boot_command_line;
1407  	bool fixed_base = false;
1408  	bool high = false;
1409  
1410  	int ret = 0;
1411  
1412  	if (!IS_ENABLED(CONFIG_KEXEC_CORE))
1413  		return;
1414  	/*
1415  	 * Don't reserve a region for a crash kernel on a crash kernel
1416  	 * since it doesn't make much sense and we have limited memory
1417  	 * resources.
1418  	 */
1419  	if (is_kdump_kernel()) {
1420  		pr_info("crashkernel: ignoring reservation request\n");
1421  		return;
1422  	}
1423  
1424  	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
1425  				&crash_size, &crash_base);
1426  	if (ret == -ENOENT) {
1427  		/* Fallback to crashkernel=X,[high,low] */
1428  		ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);
1429  		if (ret || !crash_size)
1430  			return;
1431  
1432  		/*
1433  		 * crashkernel=Y,low is valid only when crashkernel=X,high
1434  		 * is passed.
1435  		 */
1436  		ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);
1437  		if (ret == -ENOENT)
1438  			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
1439  		else if (ret)
1440  			return;
1441  
1442  		search_start = (unsigned long)dma32_phys_limit;
1443  		search_end = memblock_end_of_DRAM();
1444  		high = true;
1445  	} else if (ret || !crash_size) {
1446  		/* Invalid argument value specified */
1447  		return;
1448  	}
1449  
1450  	crash_size = PAGE_ALIGN(crash_size);
1451  
1452  	if (crash_base) {
1453  		fixed_base = true;
1454  		search_start = crash_base;
1455  		search_end = crash_base + crash_size;
1456  	}
1457  
1458  	/*
1459  	 * Current riscv boot protocol requires 2MB alignment for
1460  	 * RV64 and 4MB alignment for RV32 (hugepage size)
1461  	 *
1462  	 * Try to alloc from 32bit addressible physical memory so that
1463  	 * swiotlb can work on the crash kernel.
1464  	 */
1465  	crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
1466  					       search_start, search_end);
1467  	if (crash_base == 0) {
1468  		/*
1469  		 * For crashkernel=size[KMG]@offset[KMG], print out failure
1470  		 * message if can't reserve the specified region.
1471  		 */
1472  		if (fixed_base) {
1473  			pr_warn("crashkernel: allocating failed with given size@offset\n");
1474  			return;
1475  		}
1476  
1477  		if (high) {
1478  			/*
1479  			 * For crashkernel=size[KMG],high, if the first attempt was
1480  			 * for high memory, fall back to low memory.
1481  			 */
1482  			search_start = memblock_start_of_DRAM();
1483  			search_end = (unsigned long)dma32_phys_limit;
1484  		} else {
1485  			/*
1486  			 * For crashkernel=size[KMG], if the first attempt was for
1487  			 * low memory, fall back to high memory, the minimum required
1488  			 * low memory will be reserved later.
1489  			 */
1490  			search_start = (unsigned long)dma32_phys_limit;
1491  			search_end = memblock_end_of_DRAM();
1492  			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;
1493  		}
1494  
1495  		crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,
1496  						       search_start, search_end);
1497  		if (crash_base == 0) {
1498  			pr_warn("crashkernel: couldn't allocate %lldKB\n",
1499  				crash_size >> 10);
1500  			return;
1501  		}
1502  	}
1503  
1504  	if ((crash_base >= dma32_phys_limit) && crash_low_size &&
1505  	     reserve_crashkernel_low(crash_low_size)) {
1506  		memblock_phys_free(crash_base, crash_size);
1507  		return;
1508  	}
1509  
1510  	pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",
1511  		crash_base, crash_base + crash_size, crash_size >> 20);
1512  
1513  	crashk_res.start = crash_base;
1514  	crashk_res.end = crash_base + crash_size - 1;
1515  }
1516  
paging_init(void)1517  void __init paging_init(void)
1518  {
1519  	setup_bootmem();
1520  	setup_vm_final();
1521  
1522  	/* Depend on that Linear Mapping is ready */
1523  	memblock_allow_resize();
1524  }
1525  
misc_mem_init(void)1526  void __init misc_mem_init(void)
1527  {
1528  	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
1529  	arch_numa_init();
1530  	sparse_init();
1531  #ifdef CONFIG_SPARSEMEM_VMEMMAP
1532  	/* The entire VMEMMAP region has been populated. Flush TLB for this region */
1533  	local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END);
1534  #endif
1535  	zone_sizes_init();
1536  	reserve_crashkernel();
1537  	memblock_dump_all();
1538  }
1539  
1540  #ifdef CONFIG_SPARSEMEM_VMEMMAP
vmemmap_populate(unsigned long start,unsigned long end,int node,struct vmem_altmap * altmap)1541  int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1542  			       struct vmem_altmap *altmap)
1543  {
1544  	return vmemmap_populate_basepages(start, end, node, NULL);
1545  }
1546  #endif
1547  
1548  #if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
1549  /*
1550   * Pre-allocates page-table pages for a specific area in the kernel
1551   * page-table. Only the level which needs to be synchronized between
1552   * all page-tables is allocated because the synchronization can be
1553   * expensive.
1554   */
preallocate_pgd_pages_range(unsigned long start,unsigned long end,const char * area)1555  static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end,
1556  					       const char *area)
1557  {
1558  	unsigned long addr;
1559  	const char *lvl;
1560  
1561  	for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1562  		pgd_t *pgd = pgd_offset_k(addr);
1563  		p4d_t *p4d;
1564  		pud_t *pud;
1565  		pmd_t *pmd;
1566  
1567  		lvl = "p4d";
1568  		p4d = p4d_alloc(&init_mm, pgd, addr);
1569  		if (!p4d)
1570  			goto failed;
1571  
1572  		if (pgtable_l5_enabled)
1573  			continue;
1574  
1575  		lvl = "pud";
1576  		pud = pud_alloc(&init_mm, p4d, addr);
1577  		if (!pud)
1578  			goto failed;
1579  
1580  		if (pgtable_l4_enabled)
1581  			continue;
1582  
1583  		lvl = "pmd";
1584  		pmd = pmd_alloc(&init_mm, pud, addr);
1585  		if (!pmd)
1586  			goto failed;
1587  	}
1588  	return;
1589  
1590  failed:
1591  	/*
1592  	 * The pages have to be there now or they will be missing in
1593  	 * process page-tables later.
1594  	 */
1595  	panic("Failed to pre-allocate %s pages for %s area\n", lvl, area);
1596  }
1597  
pgtable_cache_init(void)1598  void __init pgtable_cache_init(void)
1599  {
1600  	preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
1601  	if (IS_ENABLED(CONFIG_MODULES))
1602  		preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
1603  }
1604  #endif
1605