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 #include <linux/kfence.h> 24 #include <linux/execmem.h> 25 26 #include <asm/alternative.h> 27 #include <asm/fixmap.h> 28 #include <asm/io.h> 29 #include <asm/kasan.h> 30 #include <asm/module.h> 31 #include <asm/numa.h> 32 #include <asm/pgtable.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 u64 new_vmalloc[NR_CPUS / sizeof(u64) + 1]; 41 42 struct kernel_mapping kernel_map __ro_after_init; 43 EXPORT_SYMBOL(kernel_map); 44 45 #ifdef CONFIG_64BIT 46 u64 satp_mode __ro_after_init = SATP_MODE_57; 47 #else 48 u64 satp_mode __ro_after_init = SATP_MODE_32; 49 #endif 50 EXPORT_SYMBOL(satp_mode); 51 52 #ifdef CONFIG_64BIT 53 bool pgtable_l4_enabled __ro_after_init = true; 54 bool pgtable_l5_enabled __ro_after_init = true; 55 EXPORT_SYMBOL(pgtable_l4_enabled); 56 EXPORT_SYMBOL(pgtable_l5_enabled); 57 #endif 58 59 phys_addr_t phys_ram_base __ro_after_init; 60 EXPORT_SYMBOL(phys_ram_base); 61 62 #ifdef CONFIG_SPARSEMEM_VMEMMAP 63 #define VMEMMAP_ADDR_ALIGN max(1ULL << SECTION_SIZE_BITS, \ 64 MAX_FOLIO_VMEMMAP_ALIGN) 65 66 unsigned long vmemmap_start_pfn __ro_after_init; 67 EXPORT_SYMBOL(vmemmap_start_pfn); 68 #endif 69 70 extern char _start[]; 71 void *_dtb_early_va __initdata; 72 uintptr_t _dtb_early_pa __initdata; 73 74 phys_addr_t dma32_phys_limit __initdata; 75 76 void __init arch_zone_limits_init(unsigned long *max_zone_pfns) 77 { 78 #ifdef CONFIG_ZONE_DMA32 79 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit); 80 #endif 81 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 82 } 83 84 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM) 85 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) 90 91 static inline void print_mlk(char *name, unsigned long b, unsigned long t) 92 { 93 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t, 94 (((t) - (b)) >> LOG2_SZ_1K)); 95 } 96 97 static inline void print_mlm(char *name, unsigned long b, unsigned long t) 98 { 99 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t, 100 (((t) - (b)) >> LOG2_SZ_1M)); 101 } 102 103 static inline void print_mlg(char *name, unsigned long b, unsigned long t) 104 { 105 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t, 106 (((t) - (b)) >> LOG2_SZ_1G)); 107 } 108 109 #ifdef CONFIG_64BIT 110 static inline void print_mlt(char *name, unsigned long b, unsigned long t) 111 { 112 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t, 113 (((t) - (b)) >> LOG2_SZ_1T)); 114 } 115 #else 116 #define print_mlt(n, b, t) do {} while (0) 117 #endif 118 119 static inline void print_ml(char *name, unsigned long b, unsigned long t) 120 { 121 unsigned long diff = t - b; 122 123 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); 129 else 130 print_mlk(name, b, t); 131 } 132 133 static void __init print_vm_layout(void) 134 { 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); 144 #ifdef CONFIG_64BIT 145 print_ml("modules", (unsigned long)MODULES_VADDR, 146 (unsigned long)MODULES_END); 147 #endif 148 print_ml("lowmem", (unsigned long)PAGE_OFFSET, 149 (unsigned long)high_memory); 150 if (IS_ENABLED(CONFIG_64BIT)) { 151 #ifdef CONFIG_KASAN 152 print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END); 153 #endif 154 155 print_ml("kernel", (unsigned long)kernel_map.virt_addr, 156 (unsigned long)ADDRESS_SPACE_END); 157 } 158 } 159 #else 160 static void print_vm_layout(void) { } 161 #endif /* CONFIG_DEBUG_VM */ 162 163 void __init arch_mm_preinit(void) 164 { 165 bool swiotlb = max_pfn > PFN_DOWN(dma32_phys_limit); 166 #ifdef CONFIG_FLATMEM 167 BUG_ON(!mem_map); 168 #endif /* CONFIG_FLATMEM */ 169 170 if (IS_ENABLED(CONFIG_DMA_BOUNCE_UNALIGNED_KMALLOC) && !swiotlb && 171 dma_cache_alignment != 1) { 172 /* 173 * If no bouncing needed for ZONE_DMA, allocate 1MB swiotlb 174 * buffer per 1GB of RAM for kmalloc() bouncing on 175 * non-coherent platforms. 176 */ 177 unsigned long size = 178 DIV_ROUND_UP(memblock_phys_mem_size(), 1024); 179 swiotlb_adjust_size(min(swiotlb_size_or_default(), size)); 180 swiotlb = true; 181 } 182 183 swiotlb_init(swiotlb, SWIOTLB_VERBOSE); 184 185 print_vm_layout(); 186 } 187 188 /* Limit the memory size via mem. */ 189 static phys_addr_t memory_limit; 190 191 static int __init early_mem(char *p) 192 { 193 u64 size; 194 195 if (!p) 196 return 1; 197 198 size = memparse(p, &p) & PAGE_MASK; 199 memory_limit = min_t(u64, size, memory_limit); 200 201 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20); 202 203 return 0; 204 } 205 early_param("mem", early_mem); 206 207 static void __init setup_bootmem(void) 208 { 209 phys_addr_t vmlinux_end = __pa_symbol(&_end); 210 phys_addr_t max_mapped_addr; 211 phys_addr_t phys_ram_end, vmlinux_start; 212 213 vmlinux_start = __pa_symbol(&_start); 214 215 memblock_enforce_memory_limit(memory_limit); 216 217 /* 218 * Make sure we align the reservation on PMD_SIZE since we will 219 * map the kernel in the linear mapping as read-only: we do not want 220 * any allocation to happen between _end and the next pmd aligned page. 221 */ 222 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) 223 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK; 224 /* 225 * Reserve from the start of the kernel to the end of the kernel 226 */ 227 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); 228 229 /* 230 * Make sure we align the start of the memory on a PMD boundary so that 231 * at worst, we map the linear mapping with PMD mappings. 232 */ 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 * In 64-bit, any use of __va/__pa before this point is wrong as we 240 * did not know the start of DRAM before. 241 */ 242 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU)) 243 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; 244 245 /* 246 * The size of the linear page mapping may restrict the amount of 247 * usable RAM. 248 */ 249 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU)) { 250 max_mapped_addr = __pa(PAGE_OFFSET) + KERN_VIRT_SIZE; 251 if (memblock_end_of_DRAM() > max_mapped_addr) { 252 memblock_cap_memory_range(phys_ram_base, 253 max_mapped_addr - phys_ram_base); 254 pr_warn("Physical memory overflows the linear mapping size: region above %pa removed", 255 &max_mapped_addr); 256 } 257 } 258 259 /* 260 * Reserve physical address space that would be mapped to virtual 261 * addresses greater than (void *)(-PAGE_SIZE) because: 262 * - This memory would overlap with ERR_PTR 263 * - This memory belongs to high memory, which is not supported 264 * 265 * This is not applicable to 64-bit kernel, because virtual addresses 266 * after (void *)(-PAGE_SIZE) are not linearly mapped: they are 267 * occupied by kernel mapping. Also it is unrealistic for high memory 268 * to exist on 64-bit platforms. 269 */ 270 if (!IS_ENABLED(CONFIG_64BIT)) { 271 max_mapped_addr = __va_to_pa_nodebug(-PAGE_SIZE); 272 memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr); 273 } 274 275 phys_ram_end = memblock_end_of_DRAM(); 276 min_low_pfn = PFN_UP(phys_ram_base); 277 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); 278 279 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn)); 280 281 reserve_initrd_mem(); 282 283 /* 284 * No allocation should be done before reserving the memory as defined 285 * in the device tree, otherwise the allocation could end up in a 286 * reserved region. 287 */ 288 early_init_fdt_scan_reserved_mem(); 289 290 /* 291 * If DTB is built in, no need to reserve its memblock. 292 * Otherwise, do reserve it but avoid using 293 * early_init_fdt_reserve_self() since __pa() does 294 * not work for DTB pointers that are fixmap addresses 295 */ 296 if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) 297 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); 298 299 dma_contiguous_reserve(dma32_phys_limit); 300 } 301 302 #ifdef CONFIG_RELOCATABLE 303 extern unsigned long __rela_dyn_start, __rela_dyn_end; 304 305 static void __init relocate_kernel(void) 306 { 307 Elf_Rela *rela = (Elf_Rela *)&__rela_dyn_start; 308 /* 309 * This holds the offset between the linked virtual address and the 310 * relocated virtual address. 311 */ 312 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR; 313 /* 314 * This holds the offset between kernel linked virtual address and 315 * physical address. 316 */ 317 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr; 318 319 for ( ; rela < (Elf_Rela *)&__rela_dyn_end; rela++) { 320 Elf_Addr addr = (rela->r_offset - va_kernel_link_pa_offset); 321 Elf_Addr relocated_addr = rela->r_addend; 322 323 if (rela->r_info != R_RISCV_RELATIVE) 324 continue; 325 326 /* 327 * Make sure to not relocate vdso symbols like rt_sigreturn 328 * which are linked from the address 0 in vmlinux since 329 * vdso symbol addresses are actually used as an offset from 330 * mm->context.vdso in VDSO_OFFSET macro. 331 */ 332 if (relocated_addr >= KERNEL_LINK_ADDR) 333 relocated_addr += reloc_offset; 334 335 *(Elf_Addr *)addr = relocated_addr; 336 } 337 } 338 #endif /* CONFIG_RELOCATABLE */ 339 340 #ifdef CONFIG_MMU 341 struct pt_alloc_ops pt_ops __meminitdata; 342 343 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 344 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 345 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; 346 347 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 348 349 static const pgprot_t protection_map[16] = { 350 [VM_NONE] = PAGE_NONE, 351 [VM_READ] = PAGE_READ, 352 [VM_WRITE] = PAGE_SHADOWSTACK, 353 [VM_WRITE | VM_READ] = PAGE_COPY, 354 [VM_EXEC] = PAGE_EXEC, 355 [VM_EXEC | VM_READ] = PAGE_READ_EXEC, 356 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC, 357 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC, 358 [VM_SHARED] = PAGE_NONE, 359 [VM_SHARED | VM_READ] = PAGE_READ, 360 [VM_SHARED | VM_WRITE] = PAGE_SHARED, 361 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, 362 [VM_SHARED | VM_EXEC] = PAGE_EXEC, 363 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC, 364 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC, 365 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC 366 }; 367 DECLARE_VM_GET_PAGE_PROT 368 369 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) 370 { 371 unsigned long addr = __fix_to_virt(idx); 372 pte_t *ptep; 373 374 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); 375 376 ptep = &fixmap_pte[pte_index(addr)]; 377 378 if (pgprot_val(prot)) 379 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot)); 380 else 381 pte_clear(&init_mm, addr, ptep); 382 local_flush_tlb_page(addr); 383 } 384 385 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa) 386 { 387 return (pte_t *)((uintptr_t)pa); 388 } 389 390 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa) 391 { 392 clear_fixmap(FIX_PTE); 393 return (pte_t *)set_fixmap_offset(FIX_PTE, pa); 394 } 395 396 static inline pte_t *__meminit get_pte_virt_late(phys_addr_t pa) 397 { 398 return (pte_t *) __va(pa); 399 } 400 401 static inline phys_addr_t __init alloc_pte_early(uintptr_t va) 402 { 403 /* 404 * We only create PMD or PGD early mappings so we 405 * should never reach here with MMU disabled. 406 */ 407 BUG(); 408 } 409 410 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va) 411 { 412 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 413 } 414 415 static phys_addr_t __meminit alloc_pte_late(uintptr_t va) 416 { 417 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); 418 419 /* 420 * We do not know which mm the PTE page is associated to at this point. 421 * Passing NULL to the ctor is the safe option, though it may result 422 * in unnecessary work (e.g. initialising the ptlock for init_mm). 423 */ 424 BUG_ON(!ptdesc || !pagetable_pte_ctor(NULL, ptdesc)); 425 return __pa((pte_t *)ptdesc_address(ptdesc)); 426 } 427 428 static void __meminit create_pte_mapping(pte_t *ptep, uintptr_t va, phys_addr_t pa, phys_addr_t sz, 429 pgprot_t prot) 430 { 431 uintptr_t pte_idx = pte_index(va); 432 433 BUG_ON(sz != PAGE_SIZE); 434 435 if (pte_none(ptep[pte_idx])) 436 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot); 437 } 438 439 #ifndef __PAGETABLE_PMD_FOLDED 440 441 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss; 442 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; 443 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); 444 445 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss; 446 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss; 447 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); 448 449 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; 450 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; 451 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); 452 453 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) 454 { 455 /* Before MMU is enabled */ 456 return (pmd_t *)((uintptr_t)pa); 457 } 458 459 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa) 460 { 461 clear_fixmap(FIX_PMD); 462 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa); 463 } 464 465 static pmd_t *__meminit get_pmd_virt_late(phys_addr_t pa) 466 { 467 return (pmd_t *) __va(pa); 468 } 469 470 static phys_addr_t __init alloc_pmd_early(uintptr_t va) 471 { 472 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); 473 474 return (uintptr_t)early_pmd; 475 } 476 477 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va) 478 { 479 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 480 } 481 482 static phys_addr_t __meminit alloc_pmd_late(uintptr_t va) 483 { 484 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); 485 486 /* See comment in alloc_pte_late() regarding NULL passed the ctor */ 487 BUG_ON(!ptdesc || !pagetable_pmd_ctor(NULL, ptdesc)); 488 return __pa((pmd_t *)ptdesc_address(ptdesc)); 489 } 490 491 static void __meminit create_pmd_mapping(pmd_t *pmdp, 492 uintptr_t va, phys_addr_t pa, 493 phys_addr_t sz, pgprot_t prot) 494 { 495 pte_t *ptep; 496 phys_addr_t pte_phys; 497 uintptr_t pmd_idx = pmd_index(va); 498 499 if (sz == PMD_SIZE) { 500 if (pmd_none(pmdp[pmd_idx])) 501 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot); 502 return; 503 } 504 505 if (pmd_none(pmdp[pmd_idx])) { 506 pte_phys = pt_ops.alloc_pte(va); 507 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE); 508 ptep = pt_ops.get_pte_virt(pte_phys); 509 memset(ptep, 0, PAGE_SIZE); 510 } else { 511 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx])); 512 ptep = pt_ops.get_pte_virt(pte_phys); 513 } 514 515 create_pte_mapping(ptep, va, pa, sz, prot); 516 } 517 518 static pud_t *__init get_pud_virt_early(phys_addr_t pa) 519 { 520 return (pud_t *)((uintptr_t)pa); 521 } 522 523 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa) 524 { 525 clear_fixmap(FIX_PUD); 526 return (pud_t *)set_fixmap_offset(FIX_PUD, pa); 527 } 528 529 static pud_t *__meminit get_pud_virt_late(phys_addr_t pa) 530 { 531 return (pud_t *)__va(pa); 532 } 533 534 static phys_addr_t __init alloc_pud_early(uintptr_t va) 535 { 536 /* Only one PUD is available for early mapping */ 537 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 538 539 return (uintptr_t)early_pud; 540 } 541 542 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) 543 { 544 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 545 } 546 547 static phys_addr_t __meminit alloc_pud_late(uintptr_t va) 548 { 549 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); 550 551 BUG_ON(!ptdesc); 552 pagetable_pud_ctor(ptdesc); 553 return __pa((pud_t *)ptdesc_address(ptdesc)); 554 } 555 556 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa) 557 { 558 return (p4d_t *)((uintptr_t)pa); 559 } 560 561 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa) 562 { 563 clear_fixmap(FIX_P4D); 564 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa); 565 } 566 567 static p4d_t *__meminit get_p4d_virt_late(phys_addr_t pa) 568 { 569 return (p4d_t *)__va(pa); 570 } 571 572 static phys_addr_t __init alloc_p4d_early(uintptr_t va) 573 { 574 /* Only one P4D is available for early mapping */ 575 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 576 577 return (uintptr_t)early_p4d; 578 } 579 580 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va) 581 { 582 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 583 } 584 585 static phys_addr_t __meminit alloc_p4d_late(uintptr_t va) 586 { 587 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL, 0); 588 589 BUG_ON(!ptdesc); 590 pagetable_p4d_ctor(ptdesc); 591 return __pa((p4d_t *)ptdesc_address(ptdesc)); 592 } 593 594 static void __meminit create_pud_mapping(pud_t *pudp, uintptr_t va, phys_addr_t pa, phys_addr_t sz, 595 pgprot_t prot) 596 { 597 pmd_t *nextp; 598 phys_addr_t next_phys; 599 uintptr_t pud_index = pud_index(va); 600 601 if (sz == PUD_SIZE) { 602 if (pud_val(pudp[pud_index]) == 0) 603 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot); 604 return; 605 } 606 607 if (pud_val(pudp[pud_index]) == 0) { 608 next_phys = pt_ops.alloc_pmd(va); 609 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE); 610 nextp = pt_ops.get_pmd_virt(next_phys); 611 memset(nextp, 0, PAGE_SIZE); 612 } else { 613 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index])); 614 nextp = pt_ops.get_pmd_virt(next_phys); 615 } 616 617 create_pmd_mapping(nextp, va, pa, sz, prot); 618 } 619 620 static void __meminit create_p4d_mapping(p4d_t *p4dp, uintptr_t va, phys_addr_t pa, phys_addr_t sz, 621 pgprot_t prot) 622 { 623 pud_t *nextp; 624 phys_addr_t next_phys; 625 uintptr_t p4d_index = p4d_index(va); 626 627 if (sz == P4D_SIZE) { 628 if (p4d_val(p4dp[p4d_index]) == 0) 629 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot); 630 return; 631 } 632 633 if (p4d_val(p4dp[p4d_index]) == 0) { 634 next_phys = pt_ops.alloc_pud(va); 635 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE); 636 nextp = pt_ops.get_pud_virt(next_phys); 637 memset(nextp, 0, PAGE_SIZE); 638 } else { 639 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index])); 640 nextp = pt_ops.get_pud_virt(next_phys); 641 } 642 643 create_pud_mapping(nextp, va, pa, sz, prot); 644 } 645 646 #define pgd_next_t p4d_t 647 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \ 648 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \ 649 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va))) 650 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \ 651 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \ 652 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa))) 653 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 654 (pgtable_l5_enabled ? \ 655 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \ 656 (pgtable_l4_enabled ? \ 657 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \ 658 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot))) 659 #define fixmap_pgd_next (pgtable_l5_enabled ? \ 660 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \ 661 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd)) 662 #define trampoline_pgd_next (pgtable_l5_enabled ? \ 663 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \ 664 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd)) 665 #else 666 #define pgd_next_t pte_t 667 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va) 668 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa) 669 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 670 create_pte_mapping(__nextp, __va, __pa, __sz, __prot) 671 #define fixmap_pgd_next ((uintptr_t)fixmap_pte) 672 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 673 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 674 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 675 #endif /* __PAGETABLE_PMD_FOLDED */ 676 677 void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz, 678 pgprot_t prot) 679 { 680 pgd_next_t *nextp; 681 phys_addr_t next_phys; 682 uintptr_t pgd_idx = pgd_index(va); 683 684 if (sz == PGDIR_SIZE) { 685 if (pgd_val(pgdp[pgd_idx]) == 0) 686 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot); 687 return; 688 } 689 690 if (pgd_val(pgdp[pgd_idx]) == 0) { 691 next_phys = alloc_pgd_next(va); 692 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE); 693 nextp = get_pgd_next_virt(next_phys); 694 memset(nextp, 0, PAGE_SIZE); 695 } else { 696 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx])); 697 nextp = get_pgd_next_virt(next_phys); 698 } 699 700 create_pgd_next_mapping(nextp, va, pa, sz, prot); 701 } 702 703 static uintptr_t __meminit best_map_size(phys_addr_t pa, uintptr_t va, phys_addr_t size) 704 { 705 if (debug_pagealloc_enabled()) 706 return PAGE_SIZE; 707 708 if (pgtable_l5_enabled && 709 !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE) 710 return P4D_SIZE; 711 712 if (pgtable_l4_enabled && 713 !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE) 714 return PUD_SIZE; 715 716 if (IS_ENABLED(CONFIG_64BIT) && 717 !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE) 718 return PMD_SIZE; 719 720 return PAGE_SIZE; 721 } 722 723 #ifdef CONFIG_STRICT_KERNEL_RWX 724 static __meminit pgprot_t pgprot_from_va(uintptr_t va) 725 { 726 if (is_va_kernel_text(va)) 727 return PAGE_KERNEL_READ_EXEC; 728 729 /* 730 * In 64-bit kernel, the kernel mapping is outside the linear mapping so 731 * we must protect its linear mapping alias from being executed and 732 * written. 733 * And rodata section is marked readonly in mark_rodata_ro. 734 */ 735 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va)) 736 return PAGE_KERNEL_READ; 737 738 return PAGE_KERNEL; 739 } 740 741 void mark_rodata_ro(void) 742 { 743 set_kernel_memory(__start_rodata, _data, set_memory_ro); 744 if (IS_ENABLED(CONFIG_64BIT)) 745 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data), 746 set_memory_ro); 747 } 748 #else 749 static __meminit pgprot_t pgprot_from_va(uintptr_t va) 750 { 751 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va)) 752 return PAGE_KERNEL; 753 754 return PAGE_KERNEL_EXEC; 755 } 756 #endif /* CONFIG_STRICT_KERNEL_RWX */ 757 758 #if defined(CONFIG_64BIT) 759 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa); 760 u64 __pi_set_satp_mode_from_fdt(uintptr_t dtb_pa); 761 762 static void __init disable_pgtable_l5(void) 763 { 764 pgtable_l5_enabled = false; 765 kernel_map.page_offset = PAGE_OFFSET_L4; 766 satp_mode = SATP_MODE_48; 767 } 768 769 static void __init disable_pgtable_l4(void) 770 { 771 pgtable_l4_enabled = false; 772 kernel_map.page_offset = PAGE_OFFSET_L3; 773 satp_mode = SATP_MODE_39; 774 } 775 776 static int __init print_no4lvl(char *p) 777 { 778 pr_info("Disabled 4-level and 5-level paging"); 779 return 0; 780 } 781 early_param("no4lvl", print_no4lvl); 782 783 static int __init print_no5lvl(char *p) 784 { 785 pr_info("Disabled 5-level paging"); 786 return 0; 787 } 788 early_param("no5lvl", print_no5lvl); 789 790 static void __init set_mmap_rnd_bits_max(void) 791 { 792 mmap_rnd_bits_max = MMAP_VA_BITS - PAGE_SHIFT - 3; 793 } 794 795 /* 796 * There is a simple way to determine if 4-level is supported by the 797 * underlying hardware: establish 1:1 mapping in 4-level page table mode 798 * then read SATP to see if the configuration was taken into account 799 * meaning sv48 is supported. 800 * The maximum SATP mode is limited by both the command line and the "mmu-type" 801 * property in the device tree, since some platforms may hang if an unsupported 802 * SATP mode is attempted. 803 */ 804 static __init void set_satp_mode(uintptr_t dtb_pa) 805 { 806 u64 identity_satp, hw_satp; 807 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; 808 u64 satp_mode_limit = min_not_zero(__pi_set_satp_mode_from_cmdline(dtb_pa), 809 __pi_set_satp_mode_from_fdt(dtb_pa)); 810 811 kernel_map.page_offset = PAGE_OFFSET_L5; 812 813 if (satp_mode_limit == SATP_MODE_48) { 814 disable_pgtable_l5(); 815 } else if (satp_mode_limit == SATP_MODE_39) { 816 disable_pgtable_l5(); 817 disable_pgtable_l4(); 818 return; 819 } 820 821 create_p4d_mapping(early_p4d, 822 set_satp_mode_pmd, (uintptr_t)early_pud, 823 P4D_SIZE, PAGE_TABLE); 824 create_pud_mapping(early_pud, 825 set_satp_mode_pmd, (uintptr_t)early_pmd, 826 PUD_SIZE, PAGE_TABLE); 827 /* Handle the case where set_satp_mode straddles 2 PMDs */ 828 create_pmd_mapping(early_pmd, 829 set_satp_mode_pmd, set_satp_mode_pmd, 830 PMD_SIZE, PAGE_KERNEL_EXEC); 831 create_pmd_mapping(early_pmd, 832 set_satp_mode_pmd + PMD_SIZE, 833 set_satp_mode_pmd + PMD_SIZE, 834 PMD_SIZE, PAGE_KERNEL_EXEC); 835 retry: 836 create_pgd_mapping(early_pg_dir, 837 set_satp_mode_pmd, 838 pgtable_l5_enabled ? 839 (uintptr_t)early_p4d : (uintptr_t)early_pud, 840 PGDIR_SIZE, PAGE_TABLE); 841 842 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; 843 844 local_flush_tlb_all(); 845 csr_write(CSR_SATP, identity_satp); 846 hw_satp = csr_swap(CSR_SATP, 0ULL); 847 local_flush_tlb_all(); 848 849 if (hw_satp != identity_satp) { 850 if (pgtable_l5_enabled) { 851 disable_pgtable_l5(); 852 memset(early_pg_dir, 0, PAGE_SIZE); 853 goto retry; 854 } 855 disable_pgtable_l4(); 856 } 857 858 memset(early_pg_dir, 0, PAGE_SIZE); 859 memset(early_p4d, 0, PAGE_SIZE); 860 memset(early_pud, 0, PAGE_SIZE); 861 memset(early_pmd, 0, PAGE_SIZE); 862 } 863 #endif 864 865 /* 866 * setup_vm() is called from head.S with MMU-off. 867 * 868 * Following requirements should be honoured for setup_vm() to work 869 * correctly: 870 * 1) It should use PC-relative addressing for accessing kernel symbols. 871 * To achieve this we always use GCC cmodel=medany. 872 * 2) The compiler instrumentation for FTRACE will not work for setup_vm() 873 * so disable compiler instrumentation when FTRACE is enabled. 874 * 875 * Currently, the above requirements are honoured by using custom CFLAGS 876 * for init.o in mm/Makefile. 877 */ 878 879 #ifndef __riscv_cmodel_medany 880 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing." 881 #endif 882 883 static void __init create_kernel_page_table(pgd_t *pgdir, bool early) 884 { 885 uintptr_t va, end_va; 886 887 end_va = kernel_map.virt_addr + kernel_map.size; 888 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 889 create_pgd_mapping(pgdir, va, 890 kernel_map.phys_addr + (va - kernel_map.virt_addr), 891 PMD_SIZE, 892 early ? 893 PAGE_KERNEL_EXEC : pgprot_from_va(va)); 894 } 895 896 /* 897 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel, 898 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR 899 * entry. 900 */ 901 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va, 902 uintptr_t dtb_pa) 903 { 904 #ifndef CONFIG_BUILTIN_DTB 905 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); 906 907 /* Make sure the fdt fixmap address is always aligned on PMD size */ 908 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE)); 909 910 /* In 32-bit only, the fdt lies in its own PGD */ 911 if (!IS_ENABLED(CONFIG_64BIT)) { 912 create_pgd_mapping(early_pg_dir, fix_fdt_va, 913 pa, MAX_FDT_SIZE, PAGE_KERNEL); 914 } else { 915 create_pmd_mapping(fixmap_pmd, fix_fdt_va, 916 pa, PMD_SIZE, PAGE_KERNEL); 917 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE, 918 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); 919 } 920 921 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1)); 922 #else 923 /* 924 * For 64-bit kernel, __va can't be used since it would return a linear 925 * mapping address whereas dtb_early_va will be used before 926 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the 927 * kernel is mapped in the linear mapping, that makes no difference. 928 */ 929 dtb_early_va = kernel_mapping_pa_to_va(dtb_pa); 930 #endif 931 932 dtb_early_pa = dtb_pa; 933 } 934 935 /* 936 * MMU is not enabled, the page tables are allocated directly using 937 * early_pmd/pud/p4d and the address returned is the physical one. 938 */ 939 static void __init pt_ops_set_early(void) 940 { 941 pt_ops.alloc_pte = alloc_pte_early; 942 pt_ops.get_pte_virt = get_pte_virt_early; 943 #ifndef __PAGETABLE_PMD_FOLDED 944 pt_ops.alloc_pmd = alloc_pmd_early; 945 pt_ops.get_pmd_virt = get_pmd_virt_early; 946 pt_ops.alloc_pud = alloc_pud_early; 947 pt_ops.get_pud_virt = get_pud_virt_early; 948 pt_ops.alloc_p4d = alloc_p4d_early; 949 pt_ops.get_p4d_virt = get_p4d_virt_early; 950 #endif 951 } 952 953 /* 954 * MMU is enabled but page table setup is not complete yet. 955 * fixmap page table alloc functions must be used as a means to temporarily 956 * map the allocated physical pages since the linear mapping does not exist yet. 957 * 958 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va, 959 * but it will be used as described above. 960 */ 961 static void __init pt_ops_set_fixmap(void) 962 { 963 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap); 964 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap); 965 #ifndef __PAGETABLE_PMD_FOLDED 966 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap); 967 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap); 968 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap); 969 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap); 970 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap); 971 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap); 972 #endif 973 } 974 975 /* 976 * MMU is enabled and page table setup is complete, so from now, we can use 977 * generic page allocation functions to setup page table. 978 */ 979 static void __init pt_ops_set_late(void) 980 { 981 pt_ops.alloc_pte = alloc_pte_late; 982 pt_ops.get_pte_virt = get_pte_virt_late; 983 #ifndef __PAGETABLE_PMD_FOLDED 984 pt_ops.alloc_pmd = alloc_pmd_late; 985 pt_ops.get_pmd_virt = get_pmd_virt_late; 986 pt_ops.alloc_pud = alloc_pud_late; 987 pt_ops.get_pud_virt = get_pud_virt_late; 988 pt_ops.alloc_p4d = alloc_p4d_late; 989 pt_ops.get_p4d_virt = get_p4d_virt_late; 990 #endif 991 } 992 993 #ifdef CONFIG_RANDOMIZE_BASE 994 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa); 995 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa); 996 extern u64 __init __pi_get_kaslr_seed_zkr(const uintptr_t dtb_pa); 997 998 static int __init print_nokaslr(char *p) 999 { 1000 pr_info("Disabled KASLR"); 1001 return 0; 1002 } 1003 early_param("nokaslr", print_nokaslr); 1004 #endif 1005 1006 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1007 { 1008 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1009 1010 #ifdef CONFIG_RANDOMIZE_BASE 1011 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) { 1012 u64 kaslr_seed = __pi_get_kaslr_seed_zkr(dtb_pa); 1013 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start); 1014 u32 nr_pos; 1015 1016 if (kaslr_seed == 0) 1017 kaslr_seed = __pi_get_kaslr_seed(dtb_pa); 1018 /* 1019 * Compute the number of positions available: we are limited 1020 * by the early page table that only has one PUD and we must 1021 * be aligned on PMD_SIZE. 1022 */ 1023 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE; 1024 1025 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE; 1026 } 1027 #endif 1028 1029 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset; 1030 1031 kernel_map.phys_addr = (uintptr_t)(&_start); 1032 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1033 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1034 1035 #if defined(CONFIG_64BIT) 1036 set_satp_mode(dtb_pa); 1037 set_mmap_rnd_bits_max(); 1038 #endif 1039 1040 /* 1041 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1042 * where we have the system memory layout: this allows us to align 1043 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1044 * for the linear mapping. This is only possible because the kernel 1045 * mapping lies outside the linear mapping. 1046 * In 32-bit however, as the kernel resides in the linear mapping, 1047 * setup_vm_final can not change the mapping established here, 1048 * otherwise the same kernel addresses would get mapped to different 1049 * physical addresses (if the start of dram is different from the 1050 * kernel physical address start). 1051 */ 1052 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1053 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1054 1055 memory_limit = KERN_VIRT_SIZE; 1056 1057 /* Sanity check alignment and size */ 1058 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1059 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1060 1061 #ifdef CONFIG_64BIT 1062 /* 1063 * The last 4K bytes of the addressable memory can not be mapped because 1064 * of IS_ERR_VALUE macro. 1065 */ 1066 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1067 #endif 1068 1069 #ifdef CONFIG_RELOCATABLE 1070 /* 1071 * Early page table uses only one PUD, which makes it possible 1072 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1073 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1074 * since a part of the kernel would not get mapped. 1075 */ 1076 if (IS_ENABLED(CONFIG_64BIT)) 1077 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1078 relocate_kernel(); 1079 #endif 1080 1081 apply_early_boot_alternatives(); 1082 pt_ops_set_early(); 1083 1084 /* Setup early PGD for fixmap */ 1085 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1086 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1087 1088 #ifndef __PAGETABLE_PMD_FOLDED 1089 /* Setup fixmap P4D and PUD */ 1090 if (pgtable_l5_enabled) 1091 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1092 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1093 /* Setup fixmap PUD and PMD */ 1094 if (pgtable_l4_enabled) 1095 create_pud_mapping(fixmap_pud, FIXADDR_START, 1096 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1097 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1098 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1099 /* Setup trampoline PGD and PMD */ 1100 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1101 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1102 if (pgtable_l5_enabled) 1103 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1104 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1105 if (pgtable_l4_enabled) 1106 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1107 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1108 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1109 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1110 #else 1111 /* Setup trampoline PGD */ 1112 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1113 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1114 #endif 1115 1116 /* 1117 * Setup early PGD covering entire kernel which will allow 1118 * us to reach paging_init(). We map all memory banks later 1119 * in setup_vm_final() below. 1120 */ 1121 create_kernel_page_table(early_pg_dir, true); 1122 1123 /* Setup early mapping for FDT early scan */ 1124 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1125 1126 /* 1127 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1128 * range can not span multiple pmds. 1129 */ 1130 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1131 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1132 1133 #ifndef __PAGETABLE_PMD_FOLDED 1134 /* 1135 * Early ioremap fixmap is already created as it lies within first 2MB 1136 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1137 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1138 * the user if not. 1139 */ 1140 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1141 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1142 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1143 WARN_ON(1); 1144 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1145 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1146 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1147 fix_to_virt(FIX_BTMAP_BEGIN)); 1148 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1149 fix_to_virt(FIX_BTMAP_END)); 1150 1151 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1152 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1153 } 1154 #endif 1155 1156 pt_ops_set_fixmap(); 1157 } 1158 1159 static void __meminit create_linear_mapping_range(phys_addr_t start, phys_addr_t end, 1160 uintptr_t fixed_map_size, const pgprot_t *pgprot) 1161 { 1162 phys_addr_t pa; 1163 uintptr_t va, map_size; 1164 1165 for (pa = start; pa < end; pa += map_size) { 1166 va = (uintptr_t)__va(pa); 1167 map_size = fixed_map_size ? fixed_map_size : 1168 best_map_size(pa, va, end - pa); 1169 1170 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1171 pgprot ? *pgprot : pgprot_from_va(va)); 1172 } 1173 } 1174 1175 static void __init create_linear_mapping_page_table(void) 1176 { 1177 phys_addr_t start, end; 1178 phys_addr_t kfence_pool __maybe_unused; 1179 u64 i; 1180 1181 #ifdef CONFIG_STRICT_KERNEL_RWX 1182 phys_addr_t ktext_start = __pa_symbol(_start); 1183 phys_addr_t ktext_size = __init_data_begin - _start; 1184 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1185 phys_addr_t krodata_size = _data - __start_rodata; 1186 1187 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1188 memblock_mark_nomap(ktext_start, ktext_size); 1189 memblock_mark_nomap(krodata_start, krodata_size); 1190 #endif 1191 1192 #ifdef CONFIG_KFENCE 1193 /* 1194 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1195 * before we setup the linear mapping so that we avoid using hugepages 1196 * for this region. 1197 */ 1198 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1199 BUG_ON(!kfence_pool); 1200 1201 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1202 __kfence_pool = __va(kfence_pool); 1203 #endif 1204 1205 /* Map all memory banks in the linear mapping */ 1206 for_each_mem_range(i, &start, &end) { 1207 if (start >= end) 1208 break; 1209 if (start <= __pa(PAGE_OFFSET) && 1210 __pa(PAGE_OFFSET) < end) 1211 start = __pa(PAGE_OFFSET); 1212 1213 create_linear_mapping_range(start, end, 0, NULL); 1214 } 1215 1216 #ifdef CONFIG_STRICT_KERNEL_RWX 1217 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0, NULL); 1218 create_linear_mapping_range(krodata_start, krodata_start + krodata_size, 0, NULL); 1219 1220 memblock_clear_nomap(ktext_start, ktext_size); 1221 memblock_clear_nomap(krodata_start, krodata_size); 1222 #endif 1223 1224 #ifdef CONFIG_KFENCE 1225 create_linear_mapping_range(kfence_pool, kfence_pool + KFENCE_POOL_SIZE, PAGE_SIZE, NULL); 1226 1227 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1228 #endif 1229 } 1230 1231 static void __init setup_vm_final(void) 1232 { 1233 /* Setup swapper PGD for fixmap */ 1234 #if !defined(CONFIG_64BIT) 1235 /* 1236 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1237 * directly in swapper_pg_dir in addition to the pgd entry that points 1238 * to fixmap_pte. 1239 */ 1240 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1241 1242 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1243 #endif 1244 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1245 __pa_symbol(fixmap_pgd_next), 1246 PGDIR_SIZE, PAGE_TABLE); 1247 1248 /* Map the linear mapping */ 1249 create_linear_mapping_page_table(); 1250 1251 /* Map the kernel */ 1252 if (IS_ENABLED(CONFIG_64BIT)) 1253 create_kernel_page_table(swapper_pg_dir, false); 1254 1255 #ifdef CONFIG_KASAN 1256 kasan_swapper_init(); 1257 #endif 1258 1259 /* Clear fixmap PTE and PMD mappings */ 1260 clear_fixmap(FIX_PTE); 1261 clear_fixmap(FIX_PMD); 1262 clear_fixmap(FIX_PUD); 1263 clear_fixmap(FIX_P4D); 1264 1265 /* Move to swapper page table */ 1266 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1267 local_flush_tlb_all(); 1268 1269 pt_ops_set_late(); 1270 } 1271 #else 1272 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1273 { 1274 dtb_early_va = (void *)dtb_pa; 1275 dtb_early_pa = dtb_pa; 1276 1277 #ifdef CONFIG_RELOCATABLE 1278 kernel_map.virt_addr = (uintptr_t)_start; 1279 kernel_map.phys_addr = (uintptr_t)_start; 1280 relocate_kernel(); 1281 #endif 1282 } 1283 1284 static inline void setup_vm_final(void) 1285 { 1286 } 1287 #endif /* CONFIG_MMU */ 1288 1289 /* 1290 * reserve_crashkernel() - reserves memory for crash kernel 1291 * 1292 * This function reserves memory area given in "crashkernel=" kernel command 1293 * line parameter. The memory reserved is used by dump capture kernel when 1294 * primary kernel is crashing. 1295 */ 1296 static void __init arch_reserve_crashkernel(void) 1297 { 1298 unsigned long long low_size = 0; 1299 unsigned long long crash_base, crash_size; 1300 bool high = false; 1301 int ret; 1302 1303 if (!IS_ENABLED(CONFIG_CRASH_RESERVE)) 1304 return; 1305 1306 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), 1307 &crash_size, &crash_base, 1308 &low_size, NULL, &high); 1309 if (ret) 1310 return; 1311 1312 reserve_crashkernel_generic(crash_size, crash_base, low_size, high); 1313 } 1314 1315 void __init paging_init(void) 1316 { 1317 setup_bootmem(); 1318 setup_vm_final(); 1319 1320 /* Depend on that Linear Mapping is ready */ 1321 memblock_allow_resize(); 1322 } 1323 1324 void __init misc_mem_init(void) 1325 { 1326 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1327 arch_numa_init(); 1328 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1329 /* The entire VMEMMAP region has been populated. Flush TLB for this region */ 1330 local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); 1331 #endif 1332 arch_reserve_crashkernel(); 1333 memblock_dump_all(); 1334 } 1335 1336 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1337 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, 1338 unsigned long addr, unsigned long next) 1339 { 1340 pmd_set_huge(pmd, virt_to_phys(p), PAGE_KERNEL); 1341 } 1342 1343 int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node, 1344 unsigned long addr, unsigned long next) 1345 { 1346 vmemmap_verify((pte_t *)pmdp, node, addr, next); 1347 return 1; 1348 } 1349 1350 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1351 struct vmem_altmap *altmap) 1352 { 1353 WARN_ON((start < VMEMMAP_START) || (end > VMEMMAP_END)); 1354 1355 /* 1356 * Note that SPARSEMEM_VMEMMAP is only selected for rv64 and that we 1357 * can't use hugepage mappings for 2-level page table because in case of 1358 * memory hotplug, we are not able to update all the page tables with 1359 * the new PMDs. 1360 */ 1361 return vmemmap_populate_hugepages(start, end, node, altmap); 1362 } 1363 #endif 1364 1365 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1366 /* 1367 * Pre-allocates page-table pages for a specific area in the kernel 1368 * page-table. Only the level which needs to be synchronized between 1369 * all page-tables is allocated because the synchronization can be 1370 * expensive. 1371 */ 1372 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1373 const char *area) 1374 { 1375 unsigned long addr; 1376 const char *lvl; 1377 1378 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1379 pgd_t *pgd = pgd_offset_k(addr); 1380 p4d_t *p4d; 1381 pud_t *pud; 1382 pmd_t *pmd; 1383 1384 lvl = "p4d"; 1385 p4d = p4d_alloc(&init_mm, pgd, addr); 1386 if (!p4d) 1387 goto failed; 1388 1389 if (pgtable_l5_enabled) 1390 continue; 1391 1392 lvl = "pud"; 1393 pud = pud_alloc(&init_mm, p4d, addr); 1394 if (!pud) 1395 goto failed; 1396 1397 if (pgtable_l4_enabled) 1398 continue; 1399 1400 lvl = "pmd"; 1401 pmd = pmd_alloc(&init_mm, pud, addr); 1402 if (!pmd) 1403 goto failed; 1404 } 1405 return; 1406 1407 failed: 1408 /* 1409 * The pages have to be there now or they will be missing in 1410 * process page-tables later. 1411 */ 1412 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1413 } 1414 1415 #define PAGE_END KASAN_SHADOW_START 1416 1417 void __init pgtable_cache_init(void) 1418 { 1419 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1420 if (IS_ENABLED(CONFIG_MODULES)) 1421 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1422 if (IS_ENABLED(CONFIG_MEMORY_HOTPLUG)) { 1423 preallocate_pgd_pages_range(VMEMMAP_START, VMEMMAP_END, "vmemmap"); 1424 preallocate_pgd_pages_range(PAGE_OFFSET, PAGE_END, "direct map"); 1425 if (IS_ENABLED(CONFIG_KASAN)) 1426 preallocate_pgd_pages_range(KASAN_SHADOW_START, KASAN_SHADOW_END, "kasan"); 1427 } 1428 } 1429 #endif 1430 1431 #ifdef CONFIG_EXECMEM 1432 #ifdef CONFIG_MMU 1433 static struct execmem_info execmem_info __ro_after_init; 1434 1435 struct execmem_info __init *execmem_arch_setup(void) 1436 { 1437 execmem_info = (struct execmem_info){ 1438 .ranges = { 1439 [EXECMEM_DEFAULT] = { 1440 .start = MODULES_VADDR, 1441 .end = MODULES_END, 1442 .pgprot = PAGE_KERNEL, 1443 .alignment = 1, 1444 }, 1445 [EXECMEM_KPROBES] = { 1446 .start = VMALLOC_START, 1447 .end = VMALLOC_END, 1448 .pgprot = PAGE_KERNEL_READ_EXEC, 1449 .alignment = 1, 1450 }, 1451 [EXECMEM_BPF] = { 1452 .start = BPF_JIT_REGION_START, 1453 .end = BPF_JIT_REGION_END, 1454 .pgprot = PAGE_KERNEL, 1455 .alignment = PAGE_SIZE, 1456 }, 1457 }, 1458 }; 1459 1460 return &execmem_info; 1461 } 1462 #endif /* CONFIG_MMU */ 1463 #endif /* CONFIG_EXECMEM */ 1464 1465 #ifdef CONFIG_MEMORY_HOTPLUG 1466 static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd) 1467 { 1468 struct page *page = pmd_page(*pmd); 1469 struct ptdesc *ptdesc = page_ptdesc(page); 1470 pte_t *pte; 1471 int i; 1472 1473 for (i = 0; i < PTRS_PER_PTE; i++) { 1474 pte = pte_start + i; 1475 if (!pte_none(*pte)) 1476 return; 1477 } 1478 1479 pagetable_dtor(ptdesc); 1480 if (PageReserved(page)) 1481 free_reserved_page(page); 1482 else 1483 pagetable_free(ptdesc); 1484 pmd_clear(pmd); 1485 } 1486 1487 static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud, bool is_vmemmap) 1488 { 1489 struct page *page = pud_page(*pud); 1490 struct ptdesc *ptdesc = page_ptdesc(page); 1491 pmd_t *pmd; 1492 int i; 1493 1494 for (i = 0; i < PTRS_PER_PMD; i++) { 1495 pmd = pmd_start + i; 1496 if (!pmd_none(*pmd)) 1497 return; 1498 } 1499 1500 if (!is_vmemmap) 1501 pagetable_dtor(ptdesc); 1502 if (PageReserved(page)) 1503 free_reserved_page(page); 1504 else 1505 pagetable_free(ptdesc); 1506 pud_clear(pud); 1507 } 1508 1509 static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d) 1510 { 1511 struct page *page = p4d_page(*p4d); 1512 pud_t *pud; 1513 int i; 1514 1515 for (i = 0; i < PTRS_PER_PUD; i++) { 1516 pud = pud_start + i; 1517 if (!pud_none(*pud)) 1518 return; 1519 } 1520 1521 if (PageReserved(page)) 1522 free_reserved_page(page); 1523 else 1524 __free_pages(page, 0); 1525 p4d_clear(p4d); 1526 } 1527 1528 static void __meminit free_vmemmap_storage(struct page *page, size_t size, 1529 struct vmem_altmap *altmap) 1530 { 1531 int order = get_order(size); 1532 1533 if (altmap) { 1534 vmem_altmap_free(altmap, size >> PAGE_SHIFT); 1535 return; 1536 } 1537 1538 if (PageReserved(page)) { 1539 unsigned int nr_pages = 1 << order; 1540 1541 while (nr_pages--) 1542 free_reserved_page(page++); 1543 return; 1544 } 1545 1546 __free_pages(page, order); 1547 } 1548 1549 static void __meminit remove_pte_mapping(pte_t *pte_base, unsigned long addr, unsigned long end, 1550 bool is_vmemmap, struct vmem_altmap *altmap) 1551 { 1552 unsigned long next; 1553 pte_t *ptep, pte; 1554 1555 for (; addr < end; addr = next) { 1556 next = (addr + PAGE_SIZE) & PAGE_MASK; 1557 if (next > end) 1558 next = end; 1559 1560 ptep = pte_base + pte_index(addr); 1561 pte = ptep_get(ptep); 1562 if (!pte_present(*ptep)) 1563 continue; 1564 1565 pte_clear(&init_mm, addr, ptep); 1566 if (is_vmemmap) 1567 free_vmemmap_storage(pte_page(pte), PAGE_SIZE, altmap); 1568 } 1569 } 1570 1571 static void __meminit remove_pmd_mapping(pmd_t *pmd_base, unsigned long addr, unsigned long end, 1572 bool is_vmemmap, struct vmem_altmap *altmap) 1573 { 1574 unsigned long next; 1575 pte_t *pte_base; 1576 pmd_t *pmdp, pmd; 1577 1578 for (; addr < end; addr = next) { 1579 next = pmd_addr_end(addr, end); 1580 pmdp = pmd_base + pmd_index(addr); 1581 pmd = pmdp_get(pmdp); 1582 if (!pmd_present(pmd)) 1583 continue; 1584 1585 if (pmd_leaf(pmd)) { 1586 pmd_clear(pmdp); 1587 if (is_vmemmap) 1588 free_vmemmap_storage(pmd_page(pmd), PMD_SIZE, altmap); 1589 continue; 1590 } 1591 1592 pte_base = (pte_t *)pmd_page_vaddr(*pmdp); 1593 remove_pte_mapping(pte_base, addr, next, is_vmemmap, altmap); 1594 free_pte_table(pte_base, pmdp); 1595 } 1596 } 1597 1598 static void __meminit remove_pud_mapping(pud_t *pud_base, unsigned long addr, unsigned long end, 1599 bool is_vmemmap, struct vmem_altmap *altmap) 1600 { 1601 unsigned long next; 1602 pud_t *pudp, pud; 1603 pmd_t *pmd_base; 1604 1605 for (; addr < end; addr = next) { 1606 next = pud_addr_end(addr, end); 1607 pudp = pud_base + pud_index(addr); 1608 pud = pudp_get(pudp); 1609 if (!pud_present(pud)) 1610 continue; 1611 1612 if (pud_leaf(pud)) { 1613 if (pgtable_l4_enabled) { 1614 pud_clear(pudp); 1615 if (is_vmemmap) 1616 free_vmemmap_storage(pud_page(pud), PUD_SIZE, altmap); 1617 } 1618 continue; 1619 } 1620 1621 pmd_base = pmd_offset(pudp, 0); 1622 remove_pmd_mapping(pmd_base, addr, next, is_vmemmap, altmap); 1623 1624 if (pgtable_l4_enabled) 1625 free_pmd_table(pmd_base, pudp, is_vmemmap); 1626 } 1627 } 1628 1629 static void __meminit remove_p4d_mapping(p4d_t *p4d_base, unsigned long addr, unsigned long end, 1630 bool is_vmemmap, struct vmem_altmap *altmap) 1631 { 1632 unsigned long next; 1633 p4d_t *p4dp, p4d; 1634 pud_t *pud_base; 1635 1636 for (; addr < end; addr = next) { 1637 next = p4d_addr_end(addr, end); 1638 p4dp = p4d_base + p4d_index(addr); 1639 p4d = p4dp_get(p4dp); 1640 if (!p4d_present(p4d)) 1641 continue; 1642 1643 if (p4d_leaf(p4d)) { 1644 if (pgtable_l5_enabled) { 1645 p4d_clear(p4dp); 1646 if (is_vmemmap) 1647 free_vmemmap_storage(p4d_page(p4d), P4D_SIZE, altmap); 1648 } 1649 continue; 1650 } 1651 1652 pud_base = pud_offset(p4dp, 0); 1653 remove_pud_mapping(pud_base, addr, next, is_vmemmap, altmap); 1654 1655 if (pgtable_l5_enabled) 1656 free_pud_table(pud_base, p4dp); 1657 } 1658 } 1659 1660 static void __meminit remove_pgd_mapping(unsigned long va, unsigned long end, bool is_vmemmap, 1661 struct vmem_altmap *altmap) 1662 { 1663 unsigned long addr, next; 1664 p4d_t *p4d_base; 1665 pgd_t *pgd; 1666 1667 for (addr = va; addr < end; addr = next) { 1668 next = pgd_addr_end(addr, end); 1669 pgd = pgd_offset_k(addr); 1670 1671 if (!pgd_present(*pgd)) 1672 continue; 1673 1674 if (pgd_leaf(*pgd)) 1675 continue; 1676 1677 p4d_base = p4d_offset(pgd, 0); 1678 remove_p4d_mapping(p4d_base, addr, next, is_vmemmap, altmap); 1679 } 1680 1681 flush_tlb_all(); 1682 } 1683 1684 static void __meminit remove_linear_mapping(phys_addr_t start, u64 size) 1685 { 1686 unsigned long va = (unsigned long)__va(start); 1687 unsigned long end = (unsigned long)__va(start + size); 1688 1689 remove_pgd_mapping(va, end, false, NULL); 1690 } 1691 1692 struct range arch_get_mappable_range(void) 1693 { 1694 struct range mhp_range; 1695 1696 mhp_range.start = __pa(PAGE_OFFSET); 1697 mhp_range.end = __pa(PAGE_END - 1); 1698 return mhp_range; 1699 } 1700 1701 int __ref arch_add_memory(int nid, u64 start, u64 size, struct mhp_params *params) 1702 { 1703 int ret = 0; 1704 1705 create_linear_mapping_range(start, start + size, 0, ¶ms->pgprot); 1706 ret = __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT, params); 1707 if (ret) { 1708 remove_linear_mapping(start, size); 1709 goto out; 1710 } 1711 1712 max_pfn = PFN_UP(start + size); 1713 max_low_pfn = max_pfn; 1714 1715 out: 1716 flush_tlb_all(); 1717 return ret; 1718 } 1719 1720 void __ref arch_remove_memory(u64 start, u64 size, struct vmem_altmap *altmap) 1721 { 1722 __remove_pages(start >> PAGE_SHIFT, size >> PAGE_SHIFT, altmap); 1723 remove_linear_mapping(start, size); 1724 flush_tlb_all(); 1725 } 1726 1727 void __ref vmemmap_free(unsigned long start, unsigned long end, struct vmem_altmap *altmap) 1728 { 1729 remove_pgd_mapping(start, end, true, altmap); 1730 } 1731 #endif /* CONFIG_MEMORY_HOTPLUG */ 1732