1 // SPDX-License-Identifier: GPL-2.0-only
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>
9 #include <linux/init.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>
26 #include <linux/kfence.h>
28 #include <asm/fixmap.h>
31 #include <asm/pgtable.h>
32 #include <asm/ptdump.h>
33 #include <asm/sections.h>
35 #include <asm/tlbflush.h>
37 #include "../kernel/head.h"
39 struct kernel_mapping kernel_map __ro_after_init;
40 EXPORT_SYMBOL(kernel_map);
41 #ifdef CONFIG_XIP_KERNEL
42 #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map))
46 u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39;
48 u64 satp_mode __ro_after_init = SATP_MODE_32;
50 EXPORT_SYMBOL(satp_mode);
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);
59 phys_addr_t phys_ram_base __ro_after_init;
60 EXPORT_SYMBOL(phys_ram_base);
62 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
64 EXPORT_SYMBOL(empty_zero_page);
67 void *_dtb_early_va __initdata;
68 uintptr_t _dtb_early_pa __initdata;
70 phys_addr_t dma32_phys_limit __initdata;
72 static void __init zone_sizes_init(void)
74 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, };
76 #ifdef CONFIG_ZONE_DMA32
77 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit);
79 max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
81 free_area_init(max_zone_pfns);
84 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM)
86 #define LOG2_SZ_1K ilog2(SZ_1K)
87 #define LOG2_SZ_1M ilog2(SZ_1M)
88 #define LOG2_SZ_1G ilog2(SZ_1G)
89 #define LOG2_SZ_1T ilog2(SZ_1T)
91 static inline void print_mlk(char *name, unsigned long b, unsigned long t)
93 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t,
94 (((t) - (b)) >> LOG2_SZ_1K));
97 static inline void print_mlm(char *name, unsigned long b, unsigned long t)
99 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t,
100 (((t) - (b)) >> LOG2_SZ_1M));
103 static inline void print_mlg(char *name, unsigned long b, unsigned long t)
105 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t,
106 (((t) - (b)) >> LOG2_SZ_1G));
110 static inline void print_mlt(char *name, unsigned long b, unsigned long t)
112 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t,
113 (((t) - (b)) >> LOG2_SZ_1T));
116 #define print_mlt(n, b, t) do {} while (0)
119 static inline void print_ml(char *name, unsigned long b, unsigned long t)
121 unsigned long diff = t - b;
123 if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10)
124 print_mlt(name, b, t);
125 else if ((diff >> LOG2_SZ_1G) >= 10)
126 print_mlg(name, b, t);
127 else if ((diff >> LOG2_SZ_1M) >= 10)
128 print_mlm(name, b, t);
130 print_mlk(name, b, t);
133 static void __init print_vm_layout(void)
135 pr_notice("Virtual kernel memory layout:\n");
136 print_ml("fixmap", (unsigned long)FIXADDR_START,
137 (unsigned long)FIXADDR_TOP);
138 print_ml("pci io", (unsigned long)PCI_IO_START,
139 (unsigned long)PCI_IO_END);
140 print_ml("vmemmap", (unsigned long)VMEMMAP_START,
141 (unsigned long)VMEMMAP_END);
142 print_ml("vmalloc", (unsigned long)VMALLOC_START,
143 (unsigned long)VMALLOC_END);
145 print_ml("modules", (unsigned long)MODULES_VADDR,
146 (unsigned long)MODULES_END);
148 print_ml("lowmem", (unsigned long)PAGE_OFFSET,
149 (unsigned long)high_memory);
150 if (IS_ENABLED(CONFIG_64BIT)) {
152 print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END);
155 print_ml("kernel", (unsigned long)kernel_map.virt_addr,
156 (unsigned long)ADDRESS_SPACE_END);
160 static void print_vm_layout(void) { }
161 #endif /* CONFIG_DEBUG_VM */
163 void __init mem_init(void)
165 #ifdef CONFIG_FLATMEM
167 #endif /* CONFIG_FLATMEM */
169 swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE);
175 /* Limit the memory size via mem. */
176 static phys_addr_t memory_limit;
178 static int __init early_mem(char *p)
185 size = memparse(p, &p) & PAGE_MASK;
186 memory_limit = min_t(u64, size, memory_limit);
188 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20);
192 early_param("mem", early_mem);
194 static void __init setup_bootmem(void)
196 phys_addr_t vmlinux_end = __pa_symbol(&_end);
197 phys_addr_t max_mapped_addr;
198 phys_addr_t phys_ram_end, vmlinux_start;
200 if (IS_ENABLED(CONFIG_XIP_KERNEL))
201 vmlinux_start = __pa_symbol(&_sdata);
203 vmlinux_start = __pa_symbol(&_start);
205 memblock_enforce_memory_limit(memory_limit);
208 * Make sure we align the reservation on PMD_SIZE since we will
209 * map the kernel in the linear mapping as read-only: we do not want
210 * any allocation to happen between _end and the next pmd aligned page.
212 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX))
213 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK;
215 * Reserve from the start of the kernel to the end of the kernel
217 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start);
219 phys_ram_end = memblock_end_of_DRAM();
222 * Make sure we align the start of the memory on a PMD boundary so that
223 * at worst, we map the linear mapping with PMD mappings.
225 if (!IS_ENABLED(CONFIG_XIP_KERNEL))
226 phys_ram_base = memblock_start_of_DRAM() & PMD_MASK;
229 * In 64-bit, any use of __va/__pa before this point is wrong as we
230 * did not know the start of DRAM before.
232 if (IS_ENABLED(CONFIG_64BIT))
233 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base;
236 * memblock allocator is not aware of the fact that last 4K bytes of
237 * the addressable memory can not be mapped because of IS_ERR_VALUE
238 * macro. Make sure that last 4k bytes are not usable by memblock
239 * if end of dram is equal to maximum addressable memory. For 64-bit
240 * kernel, this problem can't happen here as the end of the virtual
241 * address space is occupied by the kernel mapping then this check must
242 * be done as soon as the kernel mapping base address is determined.
244 if (!IS_ENABLED(CONFIG_64BIT)) {
245 max_mapped_addr = __pa(~(ulong)0);
246 if (max_mapped_addr == (phys_ram_end - 1))
247 memblock_set_current_limit(max_mapped_addr - 4096);
250 min_low_pfn = PFN_UP(phys_ram_base);
251 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end);
252 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn)));
254 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn));
255 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET);
257 reserve_initrd_mem();
260 * No allocation should be done before reserving the memory as defined
261 * in the device tree, otherwise the allocation could end up in a
264 early_init_fdt_scan_reserved_mem();
267 * If DTB is built in, no need to reserve its memblock.
268 * Otherwise, do reserve it but avoid using
269 * early_init_fdt_reserve_self() since __pa() does
270 * not work for DTB pointers that are fixmap addresses
272 if (!IS_ENABLED(CONFIG_BUILTIN_DTB))
273 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va));
275 dma_contiguous_reserve(dma32_phys_limit);
276 if (IS_ENABLED(CONFIG_64BIT))
277 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT);
281 struct pt_alloc_ops pt_ops __initdata;
283 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
284 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
285 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss;
287 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE);
289 #ifdef CONFIG_XIP_KERNEL
290 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops))
291 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir))
292 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte))
293 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir))
294 #endif /* CONFIG_XIP_KERNEL */
296 static const pgprot_t protection_map[16] = {
297 [VM_NONE] = PAGE_NONE,
298 [VM_READ] = PAGE_READ,
299 [VM_WRITE] = PAGE_COPY,
300 [VM_WRITE | VM_READ] = PAGE_COPY,
301 [VM_EXEC] = PAGE_EXEC,
302 [VM_EXEC | VM_READ] = PAGE_READ_EXEC,
303 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC,
304 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC,
305 [VM_SHARED] = PAGE_NONE,
306 [VM_SHARED | VM_READ] = PAGE_READ,
307 [VM_SHARED | VM_WRITE] = PAGE_SHARED,
308 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED,
309 [VM_SHARED | VM_EXEC] = PAGE_EXEC,
310 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC,
311 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC,
312 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC
314 DECLARE_VM_GET_PAGE_PROT
316 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot)
318 unsigned long addr = __fix_to_virt(idx);
321 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);
323 ptep = &fixmap_pte[pte_index(addr)];
325 if (pgprot_val(prot))
326 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
328 pte_clear(&init_mm, addr, ptep);
329 local_flush_tlb_page(addr);
332 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa)
334 return (pte_t *)((uintptr_t)pa);
337 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
339 clear_fixmap(FIX_PTE);
340 return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
343 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
345 return (pte_t *) __va(pa);
348 static inline phys_addr_t __init alloc_pte_early(uintptr_t va)
351 * We only create PMD or PGD early mappings so we
352 * should never reach here with MMU disabled.
357 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
359 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
362 static phys_addr_t __init alloc_pte_late(uintptr_t va)
364 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
366 BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc));
367 return __pa((pte_t *)ptdesc_address(ptdesc));
370 static void __init create_pte_mapping(pte_t *ptep,
371 uintptr_t va, phys_addr_t pa,
372 phys_addr_t sz, pgprot_t prot)
374 uintptr_t pte_idx = pte_index(va);
376 BUG_ON(sz != PAGE_SIZE);
378 if (pte_none(ptep[pte_idx]))
379 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot);
382 #ifndef __PAGETABLE_PMD_FOLDED
384 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss;
385 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss;
386 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE);
388 #ifdef CONFIG_XIP_KERNEL
389 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd))
390 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd))
391 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd))
392 #endif /* CONFIG_XIP_KERNEL */
394 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss;
395 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss;
396 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE);
398 #ifdef CONFIG_XIP_KERNEL
399 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d))
400 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d))
401 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d))
402 #endif /* CONFIG_XIP_KERNEL */
404 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss;
405 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss;
406 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE);
408 #ifdef CONFIG_XIP_KERNEL
409 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud))
410 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud))
411 #define early_pud ((pud_t *)XIP_FIXUP(early_pud))
412 #endif /* CONFIG_XIP_KERNEL */
414 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa)
416 /* Before MMU is enabled */
417 return (pmd_t *)((uintptr_t)pa);
420 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
422 clear_fixmap(FIX_PMD);
423 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
426 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
428 return (pmd_t *) __va(pa);
431 static phys_addr_t __init alloc_pmd_early(uintptr_t va)
433 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT);
435 return (uintptr_t)early_pmd;
438 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
440 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
443 static phys_addr_t __init alloc_pmd_late(uintptr_t va)
445 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
447 BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc));
448 return __pa((pmd_t *)ptdesc_address(ptdesc));
451 static void __init create_pmd_mapping(pmd_t *pmdp,
452 uintptr_t va, phys_addr_t pa,
453 phys_addr_t sz, pgprot_t prot)
456 phys_addr_t pte_phys;
457 uintptr_t pmd_idx = pmd_index(va);
459 if (sz == PMD_SIZE) {
460 if (pmd_none(pmdp[pmd_idx]))
461 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot);
465 if (pmd_none(pmdp[pmd_idx])) {
466 pte_phys = pt_ops.alloc_pte(va);
467 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE);
468 ptep = pt_ops.get_pte_virt(pte_phys);
469 memset(ptep, 0, PAGE_SIZE);
471 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx]));
472 ptep = pt_ops.get_pte_virt(pte_phys);
475 create_pte_mapping(ptep, va, pa, sz, prot);
478 static pud_t *__init get_pud_virt_early(phys_addr_t pa)
480 return (pud_t *)((uintptr_t)pa);
483 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
485 clear_fixmap(FIX_PUD);
486 return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
489 static pud_t *__init get_pud_virt_late(phys_addr_t pa)
491 return (pud_t *)__va(pa);
494 static phys_addr_t __init alloc_pud_early(uintptr_t va)
496 /* Only one PUD is available for early mapping */
497 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
499 return (uintptr_t)early_pud;
502 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
504 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
507 static phys_addr_t alloc_pud_late(uintptr_t va)
511 vaddr = __get_free_page(GFP_KERNEL);
516 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa)
518 return (p4d_t *)((uintptr_t)pa);
521 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
523 clear_fixmap(FIX_P4D);
524 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
527 static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
529 return (p4d_t *)__va(pa);
532 static phys_addr_t __init alloc_p4d_early(uintptr_t va)
534 /* Only one P4D is available for early mapping */
535 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT);
537 return (uintptr_t)early_p4d;
540 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
542 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
545 static phys_addr_t alloc_p4d_late(uintptr_t va)
549 vaddr = __get_free_page(GFP_KERNEL);
554 static void __init create_pud_mapping(pud_t *pudp,
555 uintptr_t va, phys_addr_t pa,
556 phys_addr_t sz, pgprot_t prot)
559 phys_addr_t next_phys;
560 uintptr_t pud_index = pud_index(va);
562 if (sz == PUD_SIZE) {
563 if (pud_val(pudp[pud_index]) == 0)
564 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot);
568 if (pud_val(pudp[pud_index]) == 0) {
569 next_phys = pt_ops.alloc_pmd(va);
570 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE);
571 nextp = pt_ops.get_pmd_virt(next_phys);
572 memset(nextp, 0, PAGE_SIZE);
574 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index]));
575 nextp = pt_ops.get_pmd_virt(next_phys);
578 create_pmd_mapping(nextp, va, pa, sz, prot);
581 static void __init create_p4d_mapping(p4d_t *p4dp,
582 uintptr_t va, phys_addr_t pa,
583 phys_addr_t sz, pgprot_t prot)
586 phys_addr_t next_phys;
587 uintptr_t p4d_index = p4d_index(va);
589 if (sz == P4D_SIZE) {
590 if (p4d_val(p4dp[p4d_index]) == 0)
591 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot);
595 if (p4d_val(p4dp[p4d_index]) == 0) {
596 next_phys = pt_ops.alloc_pud(va);
597 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE);
598 nextp = pt_ops.get_pud_virt(next_phys);
599 memset(nextp, 0, PAGE_SIZE);
601 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index]));
602 nextp = pt_ops.get_pud_virt(next_phys);
605 create_pud_mapping(nextp, va, pa, sz, prot);
608 #define pgd_next_t p4d_t
609 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \
610 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \
611 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va)))
612 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \
613 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \
614 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa)))
615 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
616 (pgtable_l5_enabled ? \
617 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \
618 (pgtable_l4_enabled ? \
619 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \
620 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot)))
621 #define fixmap_pgd_next (pgtable_l5_enabled ? \
622 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \
623 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd))
624 #define trampoline_pgd_next (pgtable_l5_enabled ? \
625 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \
626 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd))
628 #define pgd_next_t pte_t
629 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va)
630 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa)
631 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \
632 create_pte_mapping(__nextp, __va, __pa, __sz, __prot)
633 #define fixmap_pgd_next ((uintptr_t)fixmap_pte)
634 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
635 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
636 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
637 #endif /* __PAGETABLE_PMD_FOLDED */
639 void __init create_pgd_mapping(pgd_t *pgdp,
640 uintptr_t va, phys_addr_t pa,
641 phys_addr_t sz, pgprot_t prot)
644 phys_addr_t next_phys;
645 uintptr_t pgd_idx = pgd_index(va);
647 if (sz == PGDIR_SIZE) {
648 if (pgd_val(pgdp[pgd_idx]) == 0)
649 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot);
653 if (pgd_val(pgdp[pgd_idx]) == 0) {
654 next_phys = alloc_pgd_next(va);
655 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE);
656 nextp = get_pgd_next_virt(next_phys);
657 memset(nextp, 0, PAGE_SIZE);
659 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx]));
660 nextp = get_pgd_next_virt(next_phys);
663 create_pgd_next_mapping(nextp, va, pa, sz, prot);
666 static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
669 if (pgtable_l5_enabled &&
670 !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE)
673 if (pgtable_l4_enabled &&
674 !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE)
677 if (IS_ENABLED(CONFIG_64BIT) &&
678 !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE)
684 #ifdef CONFIG_XIP_KERNEL
685 #define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base))
686 extern char _xiprom[], _exiprom[], __data_loc;
688 /* called from head.S with MMU off */
689 asmlinkage void __init __copy_data(void)
691 void *from = (void *)(&__data_loc);
692 void *to = (void *)CONFIG_PHYS_RAM_BASE;
693 size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata));
695 memcpy(to, from, sz);
699 #ifdef CONFIG_STRICT_KERNEL_RWX
700 static __init pgprot_t pgprot_from_va(uintptr_t va)
702 if (is_va_kernel_text(va))
703 return PAGE_KERNEL_READ_EXEC;
706 * In 64-bit kernel, the kernel mapping is outside the linear mapping so
707 * we must protect its linear mapping alias from being executed and
709 * And rodata section is marked readonly in mark_rodata_ro.
711 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va))
712 return PAGE_KERNEL_READ;
717 void mark_rodata_ro(void)
719 set_kernel_memory(__start_rodata, _data, set_memory_ro);
720 if (IS_ENABLED(CONFIG_64BIT))
721 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data),
727 static __init pgprot_t pgprot_from_va(uintptr_t va)
729 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
732 return PAGE_KERNEL_EXEC;
734 #endif /* CONFIG_STRICT_KERNEL_RWX */
736 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
737 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa);
739 static void __init disable_pgtable_l5(void)
741 pgtable_l5_enabled = false;
742 kernel_map.page_offset = PAGE_OFFSET_L4;
743 satp_mode = SATP_MODE_48;
746 static void __init disable_pgtable_l4(void)
748 pgtable_l4_enabled = false;
749 kernel_map.page_offset = PAGE_OFFSET_L3;
750 satp_mode = SATP_MODE_39;
753 static int __init print_no4lvl(char *p)
755 pr_info("Disabled 4-level and 5-level paging");
758 early_param("no4lvl", print_no4lvl);
760 static int __init print_no5lvl(char *p)
762 pr_info("Disabled 5-level paging");
765 early_param("no5lvl", print_no5lvl);
768 * There is a simple way to determine if 4-level is supported by the
769 * underlying hardware: establish 1:1 mapping in 4-level page table mode
770 * then read SATP to see if the configuration was taken into account
771 * meaning sv48 is supported.
773 static __init void set_satp_mode(uintptr_t dtb_pa)
775 u64 identity_satp, hw_satp;
776 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK;
777 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa);
779 if (satp_mode_cmdline == SATP_MODE_57) {
780 disable_pgtable_l5();
781 } else if (satp_mode_cmdline == SATP_MODE_48) {
782 disable_pgtable_l5();
783 disable_pgtable_l4();
787 create_p4d_mapping(early_p4d,
788 set_satp_mode_pmd, (uintptr_t)early_pud,
789 P4D_SIZE, PAGE_TABLE);
790 create_pud_mapping(early_pud,
791 set_satp_mode_pmd, (uintptr_t)early_pmd,
792 PUD_SIZE, PAGE_TABLE);
793 /* Handle the case where set_satp_mode straddles 2 PMDs */
794 create_pmd_mapping(early_pmd,
795 set_satp_mode_pmd, set_satp_mode_pmd,
796 PMD_SIZE, PAGE_KERNEL_EXEC);
797 create_pmd_mapping(early_pmd,
798 set_satp_mode_pmd + PMD_SIZE,
799 set_satp_mode_pmd + PMD_SIZE,
800 PMD_SIZE, PAGE_KERNEL_EXEC);
802 create_pgd_mapping(early_pg_dir,
805 (uintptr_t)early_p4d : (uintptr_t)early_pud,
806 PGDIR_SIZE, PAGE_TABLE);
808 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode;
810 local_flush_tlb_all();
811 csr_write(CSR_SATP, identity_satp);
812 hw_satp = csr_swap(CSR_SATP, 0ULL);
813 local_flush_tlb_all();
815 if (hw_satp != identity_satp) {
816 if (pgtable_l5_enabled) {
817 disable_pgtable_l5();
818 memset(early_pg_dir, 0, PAGE_SIZE);
821 disable_pgtable_l4();
824 memset(early_pg_dir, 0, PAGE_SIZE);
825 memset(early_p4d, 0, PAGE_SIZE);
826 memset(early_pud, 0, PAGE_SIZE);
827 memset(early_pmd, 0, PAGE_SIZE);
832 * setup_vm() is called from head.S with MMU-off.
834 * Following requirements should be honoured for setup_vm() to work
836 * 1) It should use PC-relative addressing for accessing kernel symbols.
837 * To achieve this we always use GCC cmodel=medany.
838 * 2) The compiler instrumentation for FTRACE will not work for setup_vm()
839 * so disable compiler instrumentation when FTRACE is enabled.
841 * Currently, the above requirements are honoured by using custom CFLAGS
842 * for init.o in mm/Makefile.
845 #ifndef __riscv_cmodel_medany
846 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing."
849 #ifdef CONFIG_RELOCATABLE
850 extern unsigned long __rela_dyn_start, __rela_dyn_end;
852 static void __init relocate_kernel(void)
854 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start;
856 * This holds the offset between the linked virtual address and the
857 * relocated virtual address.
859 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR;
861 * This holds the offset between kernel linked virtual address and
864 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr;
866 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) {
867 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset);
868 Elf64_Addr relocated_addr = rela->r_addend;
870 if (rela->r_info != R_RISCV_RELATIVE)
874 * Make sure to not relocate vdso symbols like rt_sigreturn
875 * which are linked from the address 0 in vmlinux since
876 * vdso symbol addresses are actually used as an offset from
877 * mm->context.vdso in VDSO_OFFSET macro.
879 if (relocated_addr >= KERNEL_LINK_ADDR)
880 relocated_addr += reloc_offset;
882 *(Elf64_Addr *)addr = relocated_addr;
885 #endif /* CONFIG_RELOCATABLE */
887 #ifdef CONFIG_XIP_KERNEL
888 static void __init create_kernel_page_table(pgd_t *pgdir,
889 __always_unused bool early)
891 uintptr_t va, end_va;
893 /* Map the flash resident part */
894 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz;
895 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
896 create_pgd_mapping(pgdir, va,
897 kernel_map.xiprom + (va - kernel_map.virt_addr),
898 PMD_SIZE, PAGE_KERNEL_EXEC);
900 /* Map the data in RAM */
901 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size;
902 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE)
903 create_pgd_mapping(pgdir, va,
904 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)),
905 PMD_SIZE, PAGE_KERNEL);
908 static void __init create_kernel_page_table(pgd_t *pgdir, bool early)
910 uintptr_t va, end_va;
912 end_va = kernel_map.virt_addr + kernel_map.size;
913 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE)
914 create_pgd_mapping(pgdir, va,
915 kernel_map.phys_addr + (va - kernel_map.virt_addr),
918 PAGE_KERNEL_EXEC : pgprot_from_va(va));
923 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel,
924 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR
927 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va,
930 #ifndef CONFIG_BUILTIN_DTB
931 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1);
933 /* Make sure the fdt fixmap address is always aligned on PMD size */
934 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE));
936 /* In 32-bit only, the fdt lies in its own PGD */
937 if (!IS_ENABLED(CONFIG_64BIT)) {
938 create_pgd_mapping(early_pg_dir, fix_fdt_va,
939 pa, MAX_FDT_SIZE, PAGE_KERNEL);
941 create_pmd_mapping(fixmap_pmd, fix_fdt_va,
942 pa, PMD_SIZE, PAGE_KERNEL);
943 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE,
944 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL);
947 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1));
950 * For 64-bit kernel, __va can't be used since it would return a linear
951 * mapping address whereas dtb_early_va will be used before
952 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the
953 * kernel is mapped in the linear mapping, that makes no difference.
955 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa));
958 dtb_early_pa = dtb_pa;
962 * MMU is not enabled, the page tables are allocated directly using
963 * early_pmd/pud/p4d and the address returned is the physical one.
965 static void __init pt_ops_set_early(void)
967 pt_ops.alloc_pte = alloc_pte_early;
968 pt_ops.get_pte_virt = get_pte_virt_early;
969 #ifndef __PAGETABLE_PMD_FOLDED
970 pt_ops.alloc_pmd = alloc_pmd_early;
971 pt_ops.get_pmd_virt = get_pmd_virt_early;
972 pt_ops.alloc_pud = alloc_pud_early;
973 pt_ops.get_pud_virt = get_pud_virt_early;
974 pt_ops.alloc_p4d = alloc_p4d_early;
975 pt_ops.get_p4d_virt = get_p4d_virt_early;
980 * MMU is enabled but page table setup is not complete yet.
981 * fixmap page table alloc functions must be used as a means to temporarily
982 * map the allocated physical pages since the linear mapping does not exist yet.
984 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va,
985 * but it will be used as described above.
987 static void __init pt_ops_set_fixmap(void)
989 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap);
990 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap);
991 #ifndef __PAGETABLE_PMD_FOLDED
992 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap);
993 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap);
994 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap);
995 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap);
996 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap);
997 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap);
1002 * MMU is enabled and page table setup is complete, so from now, we can use
1003 * generic page allocation functions to setup page table.
1005 static void __init pt_ops_set_late(void)
1007 pt_ops.alloc_pte = alloc_pte_late;
1008 pt_ops.get_pte_virt = get_pte_virt_late;
1009 #ifndef __PAGETABLE_PMD_FOLDED
1010 pt_ops.alloc_pmd = alloc_pmd_late;
1011 pt_ops.get_pmd_virt = get_pmd_virt_late;
1012 pt_ops.alloc_pud = alloc_pud_late;
1013 pt_ops.get_pud_virt = get_pud_virt_late;
1014 pt_ops.alloc_p4d = alloc_p4d_late;
1015 pt_ops.get_p4d_virt = get_p4d_virt_late;
1019 #ifdef CONFIG_RANDOMIZE_BASE
1020 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa);
1021 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa);
1023 static int __init print_nokaslr(char *p)
1025 pr_info("Disabled KASLR");
1028 early_param("nokaslr", print_nokaslr);
1030 unsigned long kaslr_offset(void)
1032 return kernel_map.virt_offset;
1036 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1038 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd;
1040 #ifdef CONFIG_RANDOMIZE_BASE
1041 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) {
1042 u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa);
1043 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start);
1047 * Compute the number of positions available: we are limited
1048 * by the early page table that only has one PUD and we must
1049 * be aligned on PMD_SIZE.
1051 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE;
1053 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE;
1057 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset;
1058 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL);
1060 #ifdef CONFIG_XIP_KERNEL
1061 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR;
1062 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom);
1064 phys_ram_base = CONFIG_PHYS_RAM_BASE;
1065 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE;
1066 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata);
1068 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom;
1070 kernel_map.phys_addr = (uintptr_t)(&_start);
1071 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr;
1074 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL)
1075 set_satp_mode(dtb_pa);
1079 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem,
1080 * where we have the system memory layout: this allows us to align
1081 * the physical and virtual mappings and then make use of PUD/P4D/PGD
1082 * for the linear mapping. This is only possible because the kernel
1083 * mapping lies outside the linear mapping.
1084 * In 32-bit however, as the kernel resides in the linear mapping,
1085 * setup_vm_final can not change the mapping established here,
1086 * otherwise the same kernel addresses would get mapped to different
1087 * physical addresses (if the start of dram is different from the
1088 * kernel physical address start).
1090 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ?
1091 0UL : PAGE_OFFSET - kernel_map.phys_addr;
1092 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr;
1095 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit
1096 * kernel, whereas for 64-bit kernel, the end of the virtual address
1097 * space is occupied by the modules/BPF/kernel mappings which reduces
1098 * the available size of the linear mapping.
1100 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0);
1102 /* Sanity check alignment and size */
1103 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0);
1104 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0);
1108 * The last 4K bytes of the addressable memory can not be mapped because
1109 * of IS_ERR_VALUE macro.
1111 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K);
1114 #ifdef CONFIG_RELOCATABLE
1116 * Early page table uses only one PUD, which makes it possible
1117 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset
1118 * makes the kernel cross over a PUD_SIZE boundary, raise a bug
1119 * since a part of the kernel would not get mapped.
1121 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size);
1125 apply_early_boot_alternatives();
1128 /* Setup early PGD for fixmap */
1129 create_pgd_mapping(early_pg_dir, FIXADDR_START,
1130 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1132 #ifndef __PAGETABLE_PMD_FOLDED
1133 /* Setup fixmap P4D and PUD */
1134 if (pgtable_l5_enabled)
1135 create_p4d_mapping(fixmap_p4d, FIXADDR_START,
1136 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE);
1137 /* Setup fixmap PUD and PMD */
1138 if (pgtable_l4_enabled)
1139 create_pud_mapping(fixmap_pud, FIXADDR_START,
1140 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE);
1141 create_pmd_mapping(fixmap_pmd, FIXADDR_START,
1142 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE);
1143 /* Setup trampoline PGD and PMD */
1144 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1145 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE);
1146 if (pgtable_l5_enabled)
1147 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr,
1148 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE);
1149 if (pgtable_l4_enabled)
1150 create_pud_mapping(trampoline_pud, kernel_map.virt_addr,
1151 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE);
1152 #ifdef CONFIG_XIP_KERNEL
1153 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1154 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC);
1156 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr,
1157 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC);
1160 /* Setup trampoline PGD */
1161 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr,
1162 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC);
1166 * Setup early PGD covering entire kernel which will allow
1167 * us to reach paging_init(). We map all memory banks later
1168 * in setup_vm_final() below.
1170 create_kernel_page_table(early_pg_dir, true);
1172 /* Setup early mapping for FDT early scan */
1173 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa);
1176 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap
1177 * range can not span multiple pmds.
1179 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
1180 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
1182 #ifndef __PAGETABLE_PMD_FOLDED
1184 * Early ioremap fixmap is already created as it lies within first 2MB
1185 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END
1186 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn
1189 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))];
1190 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))];
1191 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) {
1193 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n",
1194 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd));
1195 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
1196 fix_to_virt(FIX_BTMAP_BEGIN));
1197 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n",
1198 fix_to_virt(FIX_BTMAP_END));
1200 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END);
1201 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN);
1205 pt_ops_set_fixmap();
1208 static void __init create_linear_mapping_range(phys_addr_t start,
1210 uintptr_t fixed_map_size)
1213 uintptr_t va, map_size;
1215 for (pa = start; pa < end; pa += map_size) {
1216 va = (uintptr_t)__va(pa);
1217 map_size = fixed_map_size ? fixed_map_size :
1218 best_map_size(pa, va, end - pa);
1220 create_pgd_mapping(swapper_pg_dir, va, pa, map_size,
1221 pgprot_from_va(va));
1225 static void __init create_linear_mapping_page_table(void)
1227 phys_addr_t start, end;
1228 phys_addr_t kfence_pool __maybe_unused;
1231 #ifdef CONFIG_STRICT_KERNEL_RWX
1232 phys_addr_t ktext_start = __pa_symbol(_start);
1233 phys_addr_t ktext_size = __init_data_begin - _start;
1234 phys_addr_t krodata_start = __pa_symbol(__start_rodata);
1235 phys_addr_t krodata_size = _data - __start_rodata;
1237 /* Isolate kernel text and rodata so they don't get mapped with a PUD */
1238 memblock_mark_nomap(ktext_start, ktext_size);
1239 memblock_mark_nomap(krodata_start, krodata_size);
1242 #ifdef CONFIG_KFENCE
1244 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it
1245 * before we setup the linear mapping so that we avoid using hugepages
1248 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE);
1249 BUG_ON(!kfence_pool);
1251 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE);
1252 __kfence_pool = __va(kfence_pool);
1255 /* Map all memory banks in the linear mapping */
1256 for_each_mem_range(i, &start, &end) {
1259 if (start <= __pa(PAGE_OFFSET) &&
1260 __pa(PAGE_OFFSET) < end)
1261 start = __pa(PAGE_OFFSET);
1262 if (end >= __pa(PAGE_OFFSET) + memory_limit)
1263 end = __pa(PAGE_OFFSET) + memory_limit;
1265 create_linear_mapping_range(start, end, 0);
1268 #ifdef CONFIG_STRICT_KERNEL_RWX
1269 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0);
1270 create_linear_mapping_range(krodata_start,
1271 krodata_start + krodata_size, 0);
1273 memblock_clear_nomap(ktext_start, ktext_size);
1274 memblock_clear_nomap(krodata_start, krodata_size);
1277 #ifdef CONFIG_KFENCE
1278 create_linear_mapping_range(kfence_pool,
1279 kfence_pool + KFENCE_POOL_SIZE,
1282 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
1286 static void __init setup_vm_final(void)
1288 /* Setup swapper PGD for fixmap */
1289 #if !defined(CONFIG_64BIT)
1291 * In 32-bit, the device tree lies in a pgd entry, so it must be copied
1292 * directly in swapper_pg_dir in addition to the pgd entry that points
1295 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT));
1297 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]);
1299 create_pgd_mapping(swapper_pg_dir, FIXADDR_START,
1300 __pa_symbol(fixmap_pgd_next),
1301 PGDIR_SIZE, PAGE_TABLE);
1303 /* Map the linear mapping */
1304 create_linear_mapping_page_table();
1306 /* Map the kernel */
1307 if (IS_ENABLED(CONFIG_64BIT))
1308 create_kernel_page_table(swapper_pg_dir, false);
1311 kasan_swapper_init();
1314 /* Clear fixmap PTE and PMD mappings */
1315 clear_fixmap(FIX_PTE);
1316 clear_fixmap(FIX_PMD);
1317 clear_fixmap(FIX_PUD);
1318 clear_fixmap(FIX_P4D);
1320 /* Move to swapper page table */
1321 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode);
1322 local_flush_tlb_all();
1327 asmlinkage void __init setup_vm(uintptr_t dtb_pa)
1329 dtb_early_va = (void *)dtb_pa;
1330 dtb_early_pa = dtb_pa;
1333 static inline void setup_vm_final(void)
1336 #endif /* CONFIG_MMU */
1339 * reserve_crashkernel() - reserves memory for crash kernel
1341 * This function reserves memory area given in "crashkernel=" kernel command
1342 * line parameter. The memory reserved is used by dump capture kernel when
1343 * primary kernel is crashing.
1345 static void __init arch_reserve_crashkernel(void)
1347 unsigned long long low_size = 0;
1348 unsigned long long crash_base, crash_size;
1349 char *cmdline = boot_command_line;
1353 if (!IS_ENABLED(CONFIG_KEXEC_CORE))
1356 ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),
1357 &crash_size, &crash_base,
1362 reserve_crashkernel_generic(cmdline, crash_size, crash_base,
1366 void __init paging_init(void)
1371 /* Depend on that Linear Mapping is ready */
1372 memblock_allow_resize();
1375 void __init misc_mem_init(void)
1377 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT);
1381 arch_reserve_crashkernel();
1382 memblock_dump_all();
1385 #ifdef CONFIG_SPARSEMEM_VMEMMAP
1386 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
1387 struct vmem_altmap *altmap)
1389 return vmemmap_populate_basepages(start, end, node, NULL);
1393 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT)
1395 * Pre-allocates page-table pages for a specific area in the kernel
1396 * page-table. Only the level which needs to be synchronized between
1397 * all page-tables is allocated because the synchronization can be
1400 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end,
1406 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
1407 pgd_t *pgd = pgd_offset_k(addr);
1413 p4d = p4d_alloc(&init_mm, pgd, addr);
1417 if (pgtable_l5_enabled)
1421 pud = pud_alloc(&init_mm, p4d, addr);
1425 if (pgtable_l4_enabled)
1429 pmd = pmd_alloc(&init_mm, pud, addr);
1437 * The pages have to be there now or they will be missing in
1438 * process page-tables later.
1440 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area);
1443 void __init pgtable_cache_init(void)
1445 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc");
1446 if (IS_ENABLED(CONFIG_MODULES))
1447 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules");