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/sections.h>
33#include <asm/soc.h>
34#include <asm/tlbflush.h>
35
36#include "../kernel/head.h"
37
38struct kernel_mapping kernel_map __ro_after_init;
39EXPORT_SYMBOL(kernel_map);
40#ifdef CONFIG_XIP_KERNEL
41#define kernel_map	(*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
42#endif
43
44#ifdef CONFIG_64BIT
45u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
46#else
47u64 satp_mode __ro_after_init = SATP_MODE_32;
48#endif
49EXPORT_SYMBOL(satp_mode);
50
51#ifdef CONFIG_64BIT
52bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
53bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL);
54EXPORT_SYMBOL(pgtable_l4_enabled);
55EXPORT_SYMBOL(pgtable_l5_enabled);
56#endif
57
58phys_addr_t phys_ram_base __ro_after_init;
59EXPORT_SYMBOL(phys_ram_base);
60
61unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
62							__page_aligned_bss;
63EXPORT_SYMBOL(empty_zero_page);
64
65extern char _start[];
66void *_dtb_early_va __initdata;
67uintptr_t _dtb_early_pa __initdata;
68
69phys_addr_t dma32_phys_limit __initdata;
70
71static void __init zone_sizes_init(void)
72{
73	unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
74
75#ifdef CONFIG_ZONE_DMA32
76	max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
77#endif
78	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
79
80	free_area_init(max_zone_pfns);
81}
82
83#if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
84
85#define LOG2_SZ_1K  ilog2(SZ_1K)
86#define LOG2_SZ_1M  ilog2(SZ_1M)
87#define LOG2_SZ_1G  ilog2(SZ_1G)
88#define LOG2_SZ_1T  ilog2(SZ_1T)
89
90static inline void print_mlk(char *name, unsigned long b, unsigned long t)
91{
92	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld kB)\n", name, b, t,
93		  (((t) - (b)) >> LOG2_SZ_1K));
94}
95
96static inline void print_mlm(char *name, unsigned long b, unsigned long t)
97{
98	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld MB)\n", name, b, t,
99		  (((t) - (b)) >> LOG2_SZ_1M));
100}
101
102static inline void print_mlg(char *name, unsigned long b, unsigned long t)
103{
104	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld GB)\n", name, b, t,
105		   (((t) - (b)) >> LOG2_SZ_1G));
106}
107
108#ifdef CONFIG_64BIT
109static inline void print_mlt(char *name, unsigned long b, unsigned long t)
110{
111	pr_notice("%12s : 0x%08lx - 0x%08lx   (%4ld TB)\n", name, b, t,
112		   (((t) - (b)) >> LOG2_SZ_1T));
113}
114#else
115#define print_mlt(n, b, t) do {} while (0)
116#endif
117
118static inline void print_ml(char *name, unsigned long b, unsigned long t)
119{
120	unsigned long diff = t - b;
121
122	if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
123		print_mlt(name, b, t);
124	else if ((diff >> LOG2_SZ_1G) >= 10)
125		print_mlg(name, b, t);
126	else if ((diff >> LOG2_SZ_1M) >= 10)
127		print_mlm(name, b, t);
128	else
129		print_mlk(name, b, t);
130}
131
132static void __init print_vm_layout(void)
133{
134	pr_notice("Virtual kernel memory layout:\n");
135	print_ml("fixmap", (unsigned long)FIXADDR_START,
136		(unsigned long)FIXADDR_TOP);
137	print_ml("pci io", (unsigned long)PCI_IO_START,
138		(unsigned long)PCI_IO_END);
139	print_ml("vmemmap", (unsigned long)VMEMMAP_START,
140		(unsigned long)VMEMMAP_END);
141	print_ml("vmalloc", (unsigned long)VMALLOC_START,
142		(unsigned long)VMALLOC_END);
143#ifdef CONFIG_64BIT
144	print_ml("modules", (unsigned long)MODULES_VADDR,
145		(unsigned long)MODULES_END);
146#endif
147	print_ml("lowmem", (unsigned long)PAGE_OFFSET,
148		(unsigned long)high_memory);
149	if (IS_ENABLED(CONFIG_64BIT)) {
150#ifdef CONFIG_KASAN
151		print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
152#endif
153
154		print_ml("kernel", (unsigned long)kernel_map.virt_addr,
155			 (unsigned long)ADDRESS_SPACE_END);
156	}
157}
158#else
159static void print_vm_layout(void) { }
160#endif /* CONFIG_DEBUG_VM */
161
162void __init mem_init(void)
163{
164#ifdef CONFIG_FLATMEM
165	BUG_ON(!mem_map);
166#endif /* CONFIG_FLATMEM */
167
168	swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE);
169	memblock_free_all();
170
171	print_vm_layout();
172}
173
174/* Limit the memory size via mem. */
175static phys_addr_t memory_limit;
176#ifdef CONFIG_XIP_KERNEL
177#define memory_limit	(*(phys_addr_t *)XIP_FIXUP(&memory_limit))
178#endif /* CONFIG_XIP_KERNEL */
179
180static int __init early_mem(char *p)
181{
182	u64 size;
183
184	if (!p)
185		return 1;
186
187	size = memparse(p, &p) & PAGE_MASK;
188	memory_limit = min_t(u64, size, memory_limit);
189
190	pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
191
192	return 0;
193}
194early_param("mem", early_mem);
195
196static void __init setup_bootmem(void)
197{
198	phys_addr_t vmlinux_end = __pa_symbol(&_end);
199	phys_addr_t max_mapped_addr;
200	phys_addr_t phys_ram_end, vmlinux_start;
201
202	if (IS_ENABLED(CONFIG_XIP_KERNEL))
203		vmlinux_start = __pa_symbol(&_sdata);
204	else
205		vmlinux_start = __pa_symbol(&_start);
206
207	memblock_enforce_memory_limit(memory_limit);
208
209	/*
210	 * Make sure we align the reservation on PMD_SIZE since we will
211	 * map the kernel in the linear mapping as read-only: we do not want
212	 * any allocation to happen between _end and the next pmd aligned page.
213	 */
214	if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
215		vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
216	/*
217	 * Reserve from the start of the kernel to the end of the kernel
218	 */
219	memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
220
221	phys_ram_end = memblock_end_of_DRAM();
222
223	/*
224	 * Make sure we align the start of the memory on a PMD boundary so that
225	 * at worst, we map the linear mapping with PMD mappings.
226	 */
227	if (!IS_ENABLED(CONFIG_XIP_KERNEL))
228		phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
229
230	/*
231	 * In 64-bit, any use of __va/__pa before this point is wrong as we
232	 * did not know the start of DRAM before.
233	 */
234	if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU))
235		kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
236
237	/*
238	 * memblock allocator is not aware of the fact that last 4K bytes of
239	 * the addressable memory can not be mapped because of IS_ERR_VALUE
240	 * macro. Make sure that last 4k bytes are not usable by memblock
241	 * if end of dram is equal to maximum addressable memory.  For 64-bit
242	 * kernel, this problem can't happen here as the end of the virtual
243	 * address space is occupied by the kernel mapping then this check must
244	 * be done as soon as the kernel mapping base address is determined.
245	 */
246	if (!IS_ENABLED(CONFIG_64BIT)) {
247		max_mapped_addr = __pa(~(ulong)0);
248		if (max_mapped_addr == (phys_ram_end - 1))
249			memblock_set_current_limit(max_mapped_addr - 4096);
250	}
251
252	min_low_pfn = PFN_UP(phys_ram_base);
253	max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
254	high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
255
256	dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
257	set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
258
259	reserve_initrd_mem();
260
261	/*
262	 * No allocation should be done before reserving the memory as defined
263	 * in the device tree, otherwise the allocation could end up in a
264	 * reserved region.
265	 */
266	early_init_fdt_scan_reserved_mem();
267
268	/*
269	 * If DTB is built in, no need to reserve its memblock.
270	 * Otherwise, do reserve it but avoid using
271	 * early_init_fdt_reserve_self() since __pa() does
272	 * not work for DTB pointers that are fixmap addresses
273	 */
274	if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
275		memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
276
277	dma_contiguous_reserve(dma32_phys_limit);
278	if (IS_ENABLED(CONFIG_64BIT))
279		hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
280}
281
282#ifdef CONFIG_MMU
283struct pt_alloc_ops pt_ops __initdata;
284
285pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
286pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
287static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
288
289pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
290
291#ifdef CONFIG_XIP_KERNEL
292#define pt_ops			(*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
293#define trampoline_pg_dir      ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
294#define fixmap_pte             ((pte_t *)XIP_FIXUP(fixmap_pte))
295#define early_pg_dir           ((pgd_t *)XIP_FIXUP(early_pg_dir))
296#endif /* CONFIG_XIP_KERNEL */
297
298static const pgprot_t protection_map[16] = {
299	[VM_NONE]					= PAGE_NONE,
300	[VM_READ]					= PAGE_READ,
301	[VM_WRITE]					= PAGE_COPY,
302	[VM_WRITE | VM_READ]				= PAGE_COPY,
303	[VM_EXEC]					= PAGE_EXEC,
304	[VM_EXEC | VM_READ]				= PAGE_READ_EXEC,
305	[VM_EXEC | VM_WRITE]				= PAGE_COPY_EXEC,
306	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_EXEC,
307	[VM_SHARED]					= PAGE_NONE,
308	[VM_SHARED | VM_READ]				= PAGE_READ,
309	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
310	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
311	[VM_SHARED | VM_EXEC]				= PAGE_EXEC,
312	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READ_EXEC,
313	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_EXEC,
314	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_EXEC
315};
316DECLARE_VM_GET_PAGE_PROT
317
318void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
319{
320	unsigned long addr = __fix_to_virt(idx);
321	pte_t *ptep;
322
323	BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
324
325	ptep = &fixmap_pte[pte_index(addr)];
326
327	if (pgprot_val(prot))
328		set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
329	else
330		pte_clear(&init_mm, addr, ptep);
331	local_flush_tlb_page(addr);
332}
333
334static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
335{
336	return (pte_t *)((uintptr_t)pa);
337}
338
339static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
340{
341	clear_fixmap(FIX_PTE);
342	return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
343}
344
345static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
346{
347	return (pte_t *) __va(pa);
348}
349
350static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
351{
352	/*
353	 * We only create PMD or PGD early mappings so we
354	 * should never reach here with MMU disabled.
355	 */
356	BUG();
357}
358
359static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
360{
361	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
362}
363
364static phys_addr_t __init alloc_pte_late(uintptr_t va)
365{
366	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
367
368	BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
369	return __pa((pte_t *)ptdesc_address(ptdesc));
370}
371
372static void __init create_pte_mapping(pte_t *ptep,
373				      uintptr_t va, phys_addr_t pa,
374				      phys_addr_t sz, pgprot_t prot)
375{
376	uintptr_t pte_idx = pte_index(va);
377
378	BUG_ON(sz != PAGE_SIZE);
379
380	if (pte_none(ptep[pte_idx]))
381		ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
382}
383
384#ifndef __PAGETABLE_PMD_FOLDED
385
386static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
387static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
388static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
389
390#ifdef CONFIG_XIP_KERNEL
391#define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
392#define fixmap_pmd     ((pmd_t *)XIP_FIXUP(fixmap_pmd))
393#define early_pmd      ((pmd_t *)XIP_FIXUP(early_pmd))
394#endif /* CONFIG_XIP_KERNEL */
395
396static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
397static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
398static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
399
400#ifdef CONFIG_XIP_KERNEL
401#define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
402#define fixmap_p4d     ((p4d_t *)XIP_FIXUP(fixmap_p4d))
403#define early_p4d      ((p4d_t *)XIP_FIXUP(early_p4d))
404#endif /* CONFIG_XIP_KERNEL */
405
406static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
407static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
408static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
409
410#ifdef CONFIG_XIP_KERNEL
411#define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
412#define fixmap_pud     ((pud_t *)XIP_FIXUP(fixmap_pud))
413#define early_pud      ((pud_t *)XIP_FIXUP(early_pud))
414#endif /* CONFIG_XIP_KERNEL */
415
416static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
417{
418	/* Before MMU is enabled */
419	return (pmd_t *)((uintptr_t)pa);
420}
421
422static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
423{
424	clear_fixmap(FIX_PMD);
425	return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
426}
427
428static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
429{
430	return (pmd_t *) __va(pa);
431}
432
433static phys_addr_t __init alloc_pmd_early(uintptr_t va)
434{
435	BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
436
437	return (uintptr_t)early_pmd;
438}
439
440static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
441{
442	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
443}
444
445static phys_addr_t __init alloc_pmd_late(uintptr_t va)
446{
447	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
448
449	BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
450	return __pa((pmd_t *)ptdesc_address(ptdesc));
451}
452
453static void __init create_pmd_mapping(pmd_t *pmdp,
454				      uintptr_t va, phys_addr_t pa,
455				      phys_addr_t sz, pgprot_t prot)
456{
457	pte_t *ptep;
458	phys_addr_t pte_phys;
459	uintptr_t pmd_idx = pmd_index(va);
460
461	if (sz == PMD_SIZE) {
462		if (pmd_none(pmdp[pmd_idx]))
463			pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
464		return;
465	}
466
467	if (pmd_none(pmdp[pmd_idx])) {
468		pte_phys = pt_ops.alloc_pte(va);
469		pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
470		ptep = pt_ops.get_pte_virt(pte_phys);
471		memset(ptep, 0, PAGE_SIZE);
472	} else {
473		pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
474		ptep = pt_ops.get_pte_virt(pte_phys);
475	}
476
477	create_pte_mapping(ptep, va, pa, sz, prot);
478}
479
480static pud_t *__init get_pud_virt_early(phys_addr_t pa)
481{
482	return (pud_t *)((uintptr_t)pa);
483}
484
485static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
486{
487	clear_fixmap(FIX_PUD);
488	return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
489}
490
491static pud_t *__init get_pud_virt_late(phys_addr_t pa)
492{
493	return (pud_t *)__va(pa);
494}
495
496static phys_addr_t __init alloc_pud_early(uintptr_t va)
497{
498	/* Only one PUD is available for early mapping */
499	BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
500
501	return (uintptr_t)early_pud;
502}
503
504static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
505{
506	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
507}
508
509static phys_addr_t alloc_pud_late(uintptr_t va)
510{
511	unsigned long vaddr;
512
513	vaddr = __get_free_page(GFP_KERNEL);
514	BUG_ON(!vaddr);
515	return __pa(vaddr);
516}
517
518static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
519{
520	return (p4d_t *)((uintptr_t)pa);
521}
522
523static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
524{
525	clear_fixmap(FIX_P4D);
526	return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
527}
528
529static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
530{
531	return (p4d_t *)__va(pa);
532}
533
534static phys_addr_t __init alloc_p4d_early(uintptr_t va)
535{
536	/* Only one P4D is available for early mapping */
537	BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
538
539	return (uintptr_t)early_p4d;
540}
541
542static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
543{
544	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
545}
546
547static phys_addr_t alloc_p4d_late(uintptr_t va)
548{
549	unsigned long vaddr;
550
551	vaddr = __get_free_page(GFP_KERNEL);
552	BUG_ON(!vaddr);
553	return __pa(vaddr);
554}
555
556static void __init create_pud_mapping(pud_t *pudp,
557				      uintptr_t va, phys_addr_t pa,
558				      phys_addr_t sz, pgprot_t prot)
559{
560	pmd_t *nextp;
561	phys_addr_t next_phys;
562	uintptr_t pud_index = pud_index(va);
563
564	if (sz == PUD_SIZE) {
565		if (pud_val(pudp[pud_index]) == 0)
566			pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
567		return;
568	}
569
570	if (pud_val(pudp[pud_index]) == 0) {
571		next_phys = pt_ops.alloc_pmd(va);
572		pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
573		nextp = pt_ops.get_pmd_virt(next_phys);
574		memset(nextp, 0, PAGE_SIZE);
575	} else {
576		next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
577		nextp = pt_ops.get_pmd_virt(next_phys);
578	}
579
580	create_pmd_mapping(nextp, va, pa, sz, prot);
581}
582
583static void __init create_p4d_mapping(p4d_t *p4dp,
584				      uintptr_t va, phys_addr_t pa,
585				      phys_addr_t sz, pgprot_t prot)
586{
587	pud_t *nextp;
588	phys_addr_t next_phys;
589	uintptr_t p4d_index = p4d_index(va);
590
591	if (sz == P4D_SIZE) {
592		if (p4d_val(p4dp[p4d_index]) == 0)
593			p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
594		return;
595	}
596
597	if (p4d_val(p4dp[p4d_index]) == 0) {
598		next_phys = pt_ops.alloc_pud(va);
599		p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
600		nextp = pt_ops.get_pud_virt(next_phys);
601		memset(nextp, 0, PAGE_SIZE);
602	} else {
603		next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
604		nextp = pt_ops.get_pud_virt(next_phys);
605	}
606
607	create_pud_mapping(nextp, va, pa, sz, prot);
608}
609
610#define pgd_next_t		p4d_t
611#define alloc_pgd_next(__va)	(pgtable_l5_enabled ?			\
612		pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ?		\
613		pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
614#define get_pgd_next_virt(__pa)	(pgtable_l5_enabled ?			\
615		pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ?	\
616		pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
617#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
618				(pgtable_l5_enabled ?			\
619		create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
620				(pgtable_l4_enabled ?			\
621		create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) :	\
622		create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
623#define fixmap_pgd_next		(pgtable_l5_enabled ?			\
624		(uintptr_t)fixmap_p4d : (pgtable_l4_enabled ?		\
625		(uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
626#define trampoline_pgd_next	(pgtable_l5_enabled ?			\
627		(uintptr_t)trampoline_p4d : (pgtable_l4_enabled ?	\
628		(uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
629#else
630#define pgd_next_t		pte_t
631#define alloc_pgd_next(__va)	pt_ops.alloc_pte(__va)
632#define get_pgd_next_virt(__pa)	pt_ops.get_pte_virt(__pa)
633#define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot)	\
634	create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
635#define fixmap_pgd_next		((uintptr_t)fixmap_pte)
636#define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
637#define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
638#define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
639#endif /* __PAGETABLE_PMD_FOLDED */
640
641void __init create_pgd_mapping(pgd_t *pgdp,
642				      uintptr_t va, phys_addr_t pa,
643				      phys_addr_t sz, pgprot_t prot)
644{
645	pgd_next_t *nextp;
646	phys_addr_t next_phys;
647	uintptr_t pgd_idx = pgd_index(va);
648
649	if (sz == PGDIR_SIZE) {
650		if (pgd_val(pgdp[pgd_idx]) == 0)
651			pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
652		return;
653	}
654
655	if (pgd_val(pgdp[pgd_idx]) == 0) {
656		next_phys = alloc_pgd_next(va);
657		pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
658		nextp = get_pgd_next_virt(next_phys);
659		memset(nextp, 0, PAGE_SIZE);
660	} else {
661		next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
662		nextp = get_pgd_next_virt(next_phys);
663	}
664
665	create_pgd_next_mapping(nextp, va, pa, sz, prot);
666}
667
668static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
669				      phys_addr_t size)
670{
671	if (pgtable_l5_enabled &&
672	    !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
673		return P4D_SIZE;
674
675	if (pgtable_l4_enabled &&
676	    !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
677		return PUD_SIZE;
678
679	if (IS_ENABLED(CONFIG_64BIT) &&
680	    !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
681		return PMD_SIZE;
682
683	return PAGE_SIZE;
684}
685
686#ifdef CONFIG_XIP_KERNEL
687#define phys_ram_base  (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
688extern char _xiprom[], _exiprom[], __data_loc;
689
690/* called from head.S with MMU off */
691asmlinkage void __init __copy_data(void)
692{
693	void *from = (void *)(&__data_loc);
694	void *to = (void *)CONFIG_PHYS_RAM_BASE;
695	size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
696
697	memcpy(to, from, sz);
698}
699#endif
700
701#ifdef CONFIG_STRICT_KERNEL_RWX
702static __init pgprot_t pgprot_from_va(uintptr_t va)
703{
704	if (is_va_kernel_text(va))
705		return PAGE_KERNEL_READ_EXEC;
706
707	/*
708	 * In 64-bit kernel, the kernel mapping is outside the linear mapping so
709	 * we must protect its linear mapping alias from being executed and
710	 * written.
711	 * And rodata section is marked readonly in mark_rodata_ro.
712	 */
713	if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
714		return PAGE_KERNEL_READ;
715
716	return PAGE_KERNEL;
717}
718
719void mark_rodata_ro(void)
720{
721	set_kernel_memory(__start_rodata, _data, set_memory_ro);
722	if (IS_ENABLED(CONFIG_64BIT))
723		set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
724				  set_memory_ro);
725}
726#else
727static __init pgprot_t pgprot_from_va(uintptr_t va)
728{
729	if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
730		return PAGE_KERNEL;
731
732	return PAGE_KERNEL_EXEC;
733}
734#endif /* CONFIG_STRICT_KERNEL_RWX */
735
736#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
737u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
738
739static void __init disable_pgtable_l5(void)
740{
741	pgtable_l5_enabled = false;
742	kernel_map.page_offset = PAGE_OFFSET_L4;
743	satp_mode = SATP_MODE_48;
744}
745
746static void __init disable_pgtable_l4(void)
747{
748	pgtable_l4_enabled = false;
749	kernel_map.page_offset = PAGE_OFFSET_L3;
750	satp_mode = SATP_MODE_39;
751}
752
753static int __init print_no4lvl(char *p)
754{
755	pr_info("Disabled 4-level and 5-level paging");
756	return 0;
757}
758early_param("no4lvl", print_no4lvl);
759
760static int __init print_no5lvl(char *p)
761{
762	pr_info("Disabled 5-level paging");
763	return 0;
764}
765early_param("no5lvl", print_no5lvl);
766
767static void __init set_mmap_rnd_bits_max(void)
768{
769	mmap_rnd_bits_max = MMAP_VA_BITS - PAGE_SHIFT - 3;
770}
771
772/*
773 * There is a simple way to determine if 4-level is supported by the
774 * underlying hardware: establish 1:1 mapping in 4-level page table mode
775 * then read SATP to see if the configuration was taken into account
776 * meaning sv48 is supported.
777 */
778static __init void set_satp_mode(uintptr_t dtb_pa)
779{
780	u64 identity_satp, hw_satp;
781	uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
782	u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
783
784	if (satp_mode_cmdline == SATP_MODE_57) {
785		disable_pgtable_l5();
786	} else if (satp_mode_cmdline == SATP_MODE_48) {
787		disable_pgtable_l5();
788		disable_pgtable_l4();
789		return;
790	}
791
792	create_p4d_mapping(early_p4d,
793			set_satp_mode_pmd, (uintptr_t)early_pud,
794			P4D_SIZE, PAGE_TABLE);
795	create_pud_mapping(early_pud,
796			   set_satp_mode_pmd, (uintptr_t)early_pmd,
797			   PUD_SIZE, PAGE_TABLE);
798	/* Handle the case where set_satp_mode straddles 2 PMDs */
799	create_pmd_mapping(early_pmd,
800			   set_satp_mode_pmd, set_satp_mode_pmd,
801			   PMD_SIZE, PAGE_KERNEL_EXEC);
802	create_pmd_mapping(early_pmd,
803			   set_satp_mode_pmd + PMD_SIZE,
804			   set_satp_mode_pmd + PMD_SIZE,
805			   PMD_SIZE, PAGE_KERNEL_EXEC);
806retry:
807	create_pgd_mapping(early_pg_dir,
808			   set_satp_mode_pmd,
809			   pgtable_l5_enabled ?
810				(uintptr_t)early_p4d : (uintptr_t)early_pud,
811			   PGDIR_SIZE, PAGE_TABLE);
812
813	identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
814
815	local_flush_tlb_all();
816	csr_write(CSR_SATP, identity_satp);
817	hw_satp = csr_swap(CSR_SATP, 0ULL);
818	local_flush_tlb_all();
819
820	if (hw_satp != identity_satp) {
821		if (pgtable_l5_enabled) {
822			disable_pgtable_l5();
823			memset(early_pg_dir, 0, PAGE_SIZE);
824			goto retry;
825		}
826		disable_pgtable_l4();
827	}
828
829	memset(early_pg_dir, 0, PAGE_SIZE);
830	memset(early_p4d, 0, PAGE_SIZE);
831	memset(early_pud, 0, PAGE_SIZE);
832	memset(early_pmd, 0, PAGE_SIZE);
833}
834#endif
835
836/*
837 * setup_vm() is called from head.S with MMU-off.
838 *
839 * Following requirements should be honoured for setup_vm() to work
840 * correctly:
841 * 1) It should use PC-relative addressing for accessing kernel symbols.
842 *    To achieve this we always use GCC cmodel=medany.
843 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
844 *    so disable compiler instrumentation when FTRACE is enabled.
845 *
846 * Currently, the above requirements are honoured by using custom CFLAGS
847 * for init.o in mm/Makefile.
848 */
849
850#ifndef __riscv_cmodel_medany
851#error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
852#endif
853
854#ifdef CONFIG_RELOCATABLE
855extern unsigned long __rela_dyn_start, __rela_dyn_end;
856
857static void __init relocate_kernel(void)
858{
859	Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
860	/*
861	 * This holds the offset between the linked virtual address and the
862	 * relocated virtual address.
863	 */
864	uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
865	/*
866	 * This holds the offset between kernel linked virtual address and
867	 * physical address.
868	 */
869	uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
870
871	for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
872		Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
873		Elf64_Addr relocated_addr = rela->r_addend;
874
875		if (rela->r_info != R_RISCV_RELATIVE)
876			continue;
877
878		/*
879		 * Make sure to not relocate vdso symbols like rt_sigreturn
880		 * which are linked from the address 0 in vmlinux since
881		 * vdso symbol addresses are actually used as an offset from
882		 * mm->context.vdso in VDSO_OFFSET macro.
883		 */
884		if (relocated_addr >= KERNEL_LINK_ADDR)
885			relocated_addr += reloc_offset;
886
887		*(Elf64_Addr *)addr = relocated_addr;
888	}
889}
890#endif /* CONFIG_RELOCATABLE */
891
892#ifdef CONFIG_XIP_KERNEL
893static void __init create_kernel_page_table(pgd_t *pgdir,
894					    __always_unused bool early)
895{
896	uintptr_t va, end_va;
897
898	/* Map the flash resident part */
899	end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
900	for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
901		create_pgd_mapping(pgdir, va,
902				   kernel_map.xiprom + (va - kernel_map.virt_addr),
903				   PMD_SIZE, PAGE_KERNEL_EXEC);
904
905	/* Map the data in RAM */
906	end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
907	for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
908		create_pgd_mapping(pgdir, va,
909				   kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
910				   PMD_SIZE, PAGE_KERNEL);
911}
912#else
913static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
914{
915	uintptr_t va, end_va;
916
917	end_va = kernel_map.virt_addr + kernel_map.size;
918	for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
919		create_pgd_mapping(pgdir, va,
920				   kernel_map.phys_addr + (va - kernel_map.virt_addr),
921				   PMD_SIZE,
922				   early ?
923					PAGE_KERNEL_EXEC : pgprot_from_va(va));
924}
925#endif
926
927/*
928 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
929 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
930 * entry.
931 */
932static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
933					       uintptr_t dtb_pa)
934{
935#ifndef CONFIG_BUILTIN_DTB
936	uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
937
938	/* Make sure the fdt fixmap address is always aligned on PMD size */
939	BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
940
941	/* In 32-bit only, the fdt lies in its own PGD */
942	if (!IS_ENABLED(CONFIG_64BIT)) {
943		create_pgd_mapping(early_pg_dir, fix_fdt_va,
944				   pa, MAX_FDT_SIZE, PAGE_KERNEL);
945	} else {
946		create_pmd_mapping(fixmap_pmd, fix_fdt_va,
947				   pa, PMD_SIZE, PAGE_KERNEL);
948		create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
949				   pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
950	}
951
952	dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
953#else
954	/*
955	 * For 64-bit kernel, __va can't be used since it would return a linear
956	 * mapping address whereas dtb_early_va will be used before
957	 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
958	 * kernel is mapped in the linear mapping, that makes no difference.
959	 */
960	dtb_early_va = kernel_mapping_pa_to_va(dtb_pa);
961#endif
962
963	dtb_early_pa = dtb_pa;
964}
965
966/*
967 * MMU is not enabled, the page tables are allocated directly using
968 * early_pmd/pud/p4d and the address returned is the physical one.
969 */
970static void __init pt_ops_set_early(void)
971{
972	pt_ops.alloc_pte = alloc_pte_early;
973	pt_ops.get_pte_virt = get_pte_virt_early;
974#ifndef __PAGETABLE_PMD_FOLDED
975	pt_ops.alloc_pmd = alloc_pmd_early;
976	pt_ops.get_pmd_virt = get_pmd_virt_early;
977	pt_ops.alloc_pud = alloc_pud_early;
978	pt_ops.get_pud_virt = get_pud_virt_early;
979	pt_ops.alloc_p4d = alloc_p4d_early;
980	pt_ops.get_p4d_virt = get_p4d_virt_early;
981#endif
982}
983
984/*
985 * MMU is enabled but page table setup is not complete yet.
986 * fixmap page table alloc functions must be used as a means to temporarily
987 * map the allocated physical pages since the linear mapping does not exist yet.
988 *
989 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
990 * but it will be used as described above.
991 */
992static void __init pt_ops_set_fixmap(void)
993{
994	pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
995	pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
996#ifndef __PAGETABLE_PMD_FOLDED
997	pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
998	pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
999	pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
1000	pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
1001	pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
1002	pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
1003#endif
1004}
1005
1006/*
1007 * MMU is enabled and page table setup is complete, so from now, we can use
1008 * generic page allocation functions to setup page table.
1009 */
1010static void __init pt_ops_set_late(void)
1011{
1012	pt_ops.alloc_pte = alloc_pte_late;
1013	pt_ops.get_pte_virt = get_pte_virt_late;
1014#ifndef __PAGETABLE_PMD_FOLDED
1015	pt_ops.alloc_pmd = alloc_pmd_late;
1016	pt_ops.get_pmd_virt = get_pmd_virt_late;
1017	pt_ops.alloc_pud = alloc_pud_late;
1018	pt_ops.get_pud_virt = get_pud_virt_late;
1019	pt_ops.alloc_p4d = alloc_p4d_late;
1020	pt_ops.get_p4d_virt = get_p4d_virt_late;
1021#endif
1022}
1023
1024#ifdef CONFIG_RANDOMIZE_BASE
1025extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
1026extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
1027
1028static int __init print_nokaslr(char *p)
1029{
1030	pr_info("Disabled KASLR");
1031	return 0;
1032}
1033early_param("nokaslr", print_nokaslr);
1034
1035unsigned long kaslr_offset(void)
1036{
1037	return kernel_map.virt_offset;
1038}
1039#endif
1040
1041asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1042{
1043	pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
1044
1045#ifdef CONFIG_RANDOMIZE_BASE
1046	if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
1047		u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
1048		u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
1049		u32 nr_pos;
1050
1051		/*
1052		 * Compute the number of positions available: we are limited
1053		 * by the early page table that only has one PUD and we must
1054		 * be aligned on PMD_SIZE.
1055		 */
1056		nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
1057
1058		kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
1059	}
1060#endif
1061
1062	kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
1063
1064#ifdef CONFIG_XIP_KERNEL
1065#ifdef CONFIG_64BIT
1066	kernel_map.page_offset = PAGE_OFFSET_L3;
1067#else
1068	kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1069#endif
1070	kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
1071	kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
1072
1073	phys_ram_base = CONFIG_PHYS_RAM_BASE;
1074	kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
1075	kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
1076
1077	kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
1078#else
1079	kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1080	kernel_map.phys_addr = (uintptr_t)(&_start);
1081	kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
1082#endif
1083
1084#if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
1085	set_satp_mode(dtb_pa);
1086	set_mmap_rnd_bits_max();
1087#endif
1088
1089	/*
1090	 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
1091	 * where we have the system memory layout: this allows us to align
1092	 * the physical and virtual mappings and then make use of PUD/P4D/PGD
1093	 * for the linear mapping. This is only possible because the kernel
1094	 * mapping lies outside the linear mapping.
1095	 * In 32-bit however, as the kernel resides in the linear mapping,
1096	 * setup_vm_final can not change the mapping established here,
1097	 * otherwise the same kernel addresses would get mapped to different
1098	 * physical addresses (if the start of dram is different from the
1099	 * kernel physical address start).
1100	 */
1101	kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
1102				0UL : PAGE_OFFSET - kernel_map.phys_addr;
1103	kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
1104
1105	/*
1106	 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
1107	 * kernel, whereas for 64-bit kernel, the end of the virtual address
1108	 * space is occupied by the modules/BPF/kernel mappings which reduces
1109	 * the available size of the linear mapping.
1110	 */
1111	memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
1112
1113	/* Sanity check alignment and size */
1114	BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
1115	BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
1116
1117#ifdef CONFIG_64BIT
1118	/*
1119	 * The last 4K bytes of the addressable memory can not be mapped because
1120	 * of IS_ERR_VALUE macro.
1121	 */
1122	BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
1123#endif
1124
1125#ifdef CONFIG_RELOCATABLE
1126	/*
1127	 * Early page table uses only one PUD, which makes it possible
1128	 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
1129	 * makes the kernel cross over a PUD_SIZE boundary, raise a bug
1130	 * since a part of the kernel would not get mapped.
1131	 */
1132	BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
1133	relocate_kernel();
1134#endif
1135
1136	apply_early_boot_alternatives();
1137	pt_ops_set_early();
1138
1139	/* Setup early PGD for fixmap */
1140	create_pgd_mapping(early_pg_dir, FIXADDR_START,
1141			   fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1142
1143#ifndef __PAGETABLE_PMD_FOLDED
1144	/* Setup fixmap P4D and PUD */
1145	if (pgtable_l5_enabled)
1146		create_p4d_mapping(fixmap_p4d, FIXADDR_START,
1147				   (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
1148	/* Setup fixmap PUD and PMD */
1149	if (pgtable_l4_enabled)
1150		create_pud_mapping(fixmap_pud, FIXADDR_START,
1151				   (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
1152	create_pmd_mapping(fixmap_pmd, FIXADDR_START,
1153			   (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
1154	/* Setup trampoline PGD and PMD */
1155	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1156			   trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1157	if (pgtable_l5_enabled)
1158		create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
1159				   (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
1160	if (pgtable_l4_enabled)
1161		create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
1162				   (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
1163#ifdef CONFIG_XIP_KERNEL
1164	create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1165			   kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
1166#else
1167	create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1168			   kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
1169#endif
1170#else
1171	/* Setup trampoline PGD */
1172	create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1173			   kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
1174#endif
1175
1176	/*
1177	 * Setup early PGD covering entire kernel which will allow
1178	 * us to reach paging_init(). We map all memory banks later
1179	 * in setup_vm_final() below.
1180	 */
1181	create_kernel_page_table(early_pg_dir, true);
1182
1183	/* Setup early mapping for FDT early scan */
1184	create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
1185
1186	/*
1187	 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
1188	 * range can not span multiple pmds.
1189	 */
1190	BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
1191		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
1192
1193#ifndef __PAGETABLE_PMD_FOLDED
1194	/*
1195	 * Early ioremap fixmap is already created as it lies within first 2MB
1196	 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
1197	 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
1198	 * the user if not.
1199	 */
1200	fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
1201	fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
1202	if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
1203		WARN_ON(1);
1204		pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
1205			pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
1206		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
1207			fix_to_virt(FIX_BTMAP_BEGIN));
1208		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
1209			fix_to_virt(FIX_BTMAP_END));
1210
1211		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
1212		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
1213	}
1214#endif
1215
1216	pt_ops_set_fixmap();
1217}
1218
1219static void __init create_linear_mapping_range(phys_addr_t start,
1220					       phys_addr_t end,
1221					       uintptr_t fixed_map_size)
1222{
1223	phys_addr_t pa;
1224	uintptr_t va, map_size;
1225
1226	for (pa = start; pa < end; pa += map_size) {
1227		va = (uintptr_t)__va(pa);
1228		map_size = fixed_map_size ? fixed_map_size :
1229					    best_map_size(pa, va, end - pa);
1230
1231		create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
1232				   pgprot_from_va(va));
1233	}
1234}
1235
1236static void __init create_linear_mapping_page_table(void)
1237{
1238	phys_addr_t start, end;
1239	phys_addr_t kfence_pool __maybe_unused;
1240	u64 i;
1241
1242#ifdef CONFIG_STRICT_KERNEL_RWX
1243	phys_addr_t ktext_start = __pa_symbol(_start);
1244	phys_addr_t ktext_size = __init_data_begin - _start;
1245	phys_addr_t krodata_start = __pa_symbol(__start_rodata);
1246	phys_addr_t krodata_size = _data - __start_rodata;
1247
1248	/* Isolate kernel text and rodata so they don't get mapped with a PUD */
1249	memblock_mark_nomap(ktext_start,  ktext_size);
1250	memblock_mark_nomap(krodata_start, krodata_size);
1251#endif
1252
1253#ifdef CONFIG_KFENCE
1254	/*
1255	 *  kfence pool must be backed by PAGE_SIZE mappings, so allocate it
1256	 *  before we setup the linear mapping so that we avoid using hugepages
1257	 *  for this region.
1258	 */
1259	kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
1260	BUG_ON(!kfence_pool);
1261
1262	memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
1263	__kfence_pool = __va(kfence_pool);
1264#endif
1265
1266	/* Map all memory banks in the linear mapping */
1267	for_each_mem_range(i, &start, &end) {
1268		if (start >= end)
1269			break;
1270		if (start <= __pa(PAGE_OFFSET) &&
1271		    __pa(PAGE_OFFSET) < end)
1272			start = __pa(PAGE_OFFSET);
1273		if (end >= __pa(PAGE_OFFSET) + memory_limit)
1274			end = __pa(PAGE_OFFSET) + memory_limit;
1275
1276		create_linear_mapping_range(start, end, 0);
1277	}
1278
1279#ifdef CONFIG_STRICT_KERNEL_RWX
1280	create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0);
1281	create_linear_mapping_range(krodata_start,
1282				    krodata_start + krodata_size, 0);
1283
1284	memblock_clear_nomap(ktext_start,  ktext_size);
1285	memblock_clear_nomap(krodata_start, krodata_size);
1286#endif
1287
1288#ifdef CONFIG_KFENCE
1289	create_linear_mapping_range(kfence_pool,
1290				    kfence_pool + KFENCE_POOL_SIZE,
1291				    PAGE_SIZE);
1292
1293	memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
1294#endif
1295}
1296
1297static void __init setup_vm_final(void)
1298{
1299	/* Setup swapper PGD for fixmap */
1300#if !defined(CONFIG_64BIT)
1301	/*
1302	 * In 32-bit, the device tree lies in a pgd entry, so it must be copied
1303	 * directly in swapper_pg_dir in addition to the pgd entry that points
1304	 * to fixmap_pte.
1305	 */
1306	unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
1307
1308	set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
1309#endif
1310	create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
1311			   __pa_symbol(fixmap_pgd_next),
1312			   PGDIR_SIZE, PAGE_TABLE);
1313
1314	/* Map the linear mapping */
1315	create_linear_mapping_page_table();
1316
1317	/* Map the kernel */
1318	if (IS_ENABLED(CONFIG_64BIT))
1319		create_kernel_page_table(swapper_pg_dir, false);
1320
1321#ifdef CONFIG_KASAN
1322	kasan_swapper_init();
1323#endif
1324
1325	/* Clear fixmap PTE and PMD mappings */
1326	clear_fixmap(FIX_PTE);
1327	clear_fixmap(FIX_PMD);
1328	clear_fixmap(FIX_PUD);
1329	clear_fixmap(FIX_P4D);
1330
1331	/* Move to swapper page table */
1332	csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
1333	local_flush_tlb_all();
1334
1335	pt_ops_set_late();
1336}
1337#else
1338asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1339{
1340	dtb_early_va = (void *)dtb_pa;
1341	dtb_early_pa = dtb_pa;
1342}
1343
1344static inline void setup_vm_final(void)
1345{
1346}
1347#endif /* CONFIG_MMU */
1348
1349/*
1350 * reserve_crashkernel() - reserves memory for crash kernel
1351 *
1352 * This function reserves memory area given in "crashkernel=" kernel command
1353 * line parameter. The memory reserved is used by dump capture kernel when
1354 * primary kernel is crashing.
1355 */
1356static void __init arch_reserve_crashkernel(void)
1357{
1358	unsigned long long low_size = 0;
1359	unsigned long long crash_base, crash_size;
1360	char *cmdline = boot_command_line;
1361	bool high = false;
1362	int ret;
1363
1364	if (!IS_ENABLED(CONFIG_CRASH_RESERVE))
1365		return;
1366
1367	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
1368				&crash_size, &crash_base,
1369				&low_size, &high);
1370	if (ret)
1371		return;
1372
1373	reserve_crashkernel_generic(cmdline, crash_size, crash_base,
1374				    low_size, high);
1375}
1376
1377void __init paging_init(void)
1378{
1379	setup_bootmem();
1380	setup_vm_final();
1381
1382	/* Depend on that Linear Mapping is ready */
1383	memblock_allow_resize();
1384}
1385
1386void __init misc_mem_init(void)
1387{
1388	early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
1389	arch_numa_init();
1390	sparse_init();
1391#ifdef CONFIG_SPARSEMEM_VMEMMAP
1392	/* The entire VMEMMAP region has been populated. Flush TLB for this region */
1393	local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END);
1394#endif
1395	zone_sizes_init();
1396	arch_reserve_crashkernel();
1397	memblock_dump_all();
1398}
1399
1400#ifdef CONFIG_SPARSEMEM_VMEMMAP
1401void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
1402			       unsigned long addr, unsigned long next)
1403{
1404	pmd_set_huge(pmd, virt_to_phys(p), PAGE_KERNEL);
1405}
1406
1407int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node,
1408				unsigned long addr, unsigned long next)
1409{
1410	vmemmap_verify((pte_t *)pmdp, node, addr, next);
1411	return 1;
1412}
1413
1414int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1415			       struct vmem_altmap *altmap)
1416{
1417	/*
1418	 * Note that SPARSEMEM_VMEMMAP is only selected for rv64 and that we
1419	 * can't use hugepage mappings for 2-level page table because in case of
1420	 * memory hotplug, we are not able to update all the page tables with
1421	 * the new PMDs.
1422	 */
1423	return vmemmap_populate_hugepages(start, end, node, NULL);
1424}
1425#endif
1426
1427#if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
1428/*
1429 * Pre-allocates page-table pages for a specific area in the kernel
1430 * page-table. Only the level which needs to be synchronized between
1431 * all page-tables is allocated because the synchronization can be
1432 * expensive.
1433 */
1434static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end,
1435					       const char *area)
1436{
1437	unsigned long addr;
1438	const char *lvl;
1439
1440	for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1441		pgd_t *pgd = pgd_offset_k(addr);
1442		p4d_t *p4d;
1443		pud_t *pud;
1444		pmd_t *pmd;
1445
1446		lvl = "p4d";
1447		p4d = p4d_alloc(&init_mm, pgd, addr);
1448		if (!p4d)
1449			goto failed;
1450
1451		if (pgtable_l5_enabled)
1452			continue;
1453
1454		lvl = "pud";
1455		pud = pud_alloc(&init_mm, p4d, addr);
1456		if (!pud)
1457			goto failed;
1458
1459		if (pgtable_l4_enabled)
1460			continue;
1461
1462		lvl = "pmd";
1463		pmd = pmd_alloc(&init_mm, pud, addr);
1464		if (!pmd)
1465			goto failed;
1466	}
1467	return;
1468
1469failed:
1470	/*
1471	 * The pages have to be there now or they will be missing in
1472	 * process page-tables later.
1473	 */
1474	panic("Failed to pre-allocate %s pages for %s area\n", lvl, area);
1475}
1476
1477void __init pgtable_cache_init(void)
1478{
1479	preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
1480	if (IS_ENABLED(CONFIG_MODULES))
1481		preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");
1482}
1483#endif
1484