1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Regents of the University of California 4 * Copyright (C) 2019 Western Digital Corporation or its affiliates. 5 * Copyright (C) 2020 FORTH-ICS/CARV 6 * Nick Kossifidis <mick@ics.forth.gr> 7 */ 8 9 #include <linux/init.h> 10 #include <linux/mm.h> 11 #include <linux/memblock.h> 12 #include <linux/initrd.h> 13 #include <linux/swap.h> 14 #include <linux/swiotlb.h> 15 #include <linux/sizes.h> 16 #include <linux/of_fdt.h> 17 #include <linux/of_reserved_mem.h> 18 #include <linux/libfdt.h> 19 #include <linux/set_memory.h> 20 #include <linux/dma-map-ops.h> 21 #include <linux/crash_dump.h> 22 #include <linux/hugetlb.h> 23 #ifdef CONFIG_RELOCATABLE 24 #include <linux/elf.h> 25 #endif 26 #include <linux/kfence.h> 27 28 #include <asm/fixmap.h> 29 #include <asm/io.h> 30 #include <asm/numa.h> 31 #include <asm/pgtable.h> 32 #include <asm/ptdump.h> 33 #include <asm/sections.h> 34 #include <asm/soc.h> 35 #include <asm/tlbflush.h> 36 37 #include "../kernel/head.h" 38 39 struct kernel_mapping kernel_map __ro_after_init; 40 EXPORT_SYMBOL(kernel_map); 41 #ifdef CONFIG_XIP_KERNEL 42 #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map)) 43 #endif 44 45 #ifdef CONFIG_64BIT 46 u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39; 47 #else 48 u64 satp_mode __ro_after_init = SATP_MODE_32; 49 #endif 50 EXPORT_SYMBOL(satp_mode); 51 52 bool pgtable_l4_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL); 53 bool pgtable_l5_enabled = IS_ENABLED(CONFIG_64BIT) && !IS_ENABLED(CONFIG_XIP_KERNEL); 54 EXPORT_SYMBOL(pgtable_l4_enabled); 55 EXPORT_SYMBOL(pgtable_l5_enabled); 56 57 phys_addr_t phys_ram_base __ro_after_init; 58 EXPORT_SYMBOL(phys_ram_base); 59 60 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] 61 __page_aligned_bss; 62 EXPORT_SYMBOL(empty_zero_page); 63 64 extern char _start[]; 65 void *_dtb_early_va __initdata; 66 uintptr_t _dtb_early_pa __initdata; 67 68 static phys_addr_t dma32_phys_limit __initdata; 69 70 static void __init zone_sizes_init(void) 71 { 72 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; 73 74 #ifdef CONFIG_ZONE_DMA32 75 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit); 76 #endif 77 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 78 79 free_area_init(max_zone_pfns); 80 } 81 82 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM) 83 84 #define LOG2_SZ_1K ilog2(SZ_1K) 85 #define LOG2_SZ_1M ilog2(SZ_1M) 86 #define LOG2_SZ_1G ilog2(SZ_1G) 87 #define LOG2_SZ_1T ilog2(SZ_1T) 88 89 static inline void print_mlk(char *name, unsigned long b, unsigned long t) 90 { 91 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t, 92 (((t) - (b)) >> LOG2_SZ_1K)); 93 } 94 95 static inline void print_mlm(char *name, unsigned long b, unsigned long t) 96 { 97 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t, 98 (((t) - (b)) >> LOG2_SZ_1M)); 99 } 100 101 static inline void print_mlg(char *name, unsigned long b, unsigned long t) 102 { 103 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t, 104 (((t) - (b)) >> LOG2_SZ_1G)); 105 } 106 107 #ifdef CONFIG_64BIT 108 static inline void print_mlt(char *name, unsigned long b, unsigned long t) 109 { 110 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t, 111 (((t) - (b)) >> LOG2_SZ_1T)); 112 } 113 #else 114 #define print_mlt(n, b, t) do {} while (0) 115 #endif 116 117 static inline void print_ml(char *name, unsigned long b, unsigned long t) 118 { 119 unsigned long diff = t - b; 120 121 if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10) 122 print_mlt(name, b, t); 123 else if ((diff >> LOG2_SZ_1G) >= 10) 124 print_mlg(name, b, t); 125 else if ((diff >> LOG2_SZ_1M) >= 10) 126 print_mlm(name, b, t); 127 else 128 print_mlk(name, b, t); 129 } 130 131 static void __init print_vm_layout(void) 132 { 133 pr_notice("Virtual kernel memory layout:\n"); 134 print_ml("fixmap", (unsigned long)FIXADDR_START, 135 (unsigned long)FIXADDR_TOP); 136 print_ml("pci io", (unsigned long)PCI_IO_START, 137 (unsigned long)PCI_IO_END); 138 print_ml("vmemmap", (unsigned long)VMEMMAP_START, 139 (unsigned long)VMEMMAP_END); 140 print_ml("vmalloc", (unsigned long)VMALLOC_START, 141 (unsigned long)VMALLOC_END); 142 #ifdef CONFIG_64BIT 143 print_ml("modules", (unsigned long)MODULES_VADDR, 144 (unsigned long)MODULES_END); 145 #endif 146 print_ml("lowmem", (unsigned long)PAGE_OFFSET, 147 (unsigned long)high_memory); 148 if (IS_ENABLED(CONFIG_64BIT)) { 149 #ifdef CONFIG_KASAN 150 print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END); 151 #endif 152 153 print_ml("kernel", (unsigned long)kernel_map.virt_addr, 154 (unsigned long)ADDRESS_SPACE_END); 155 } 156 } 157 #else 158 static void print_vm_layout(void) { } 159 #endif /* CONFIG_DEBUG_VM */ 160 161 void __init mem_init(void) 162 { 163 #ifdef CONFIG_FLATMEM 164 BUG_ON(!mem_map); 165 #endif /* CONFIG_FLATMEM */ 166 167 swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE); 168 memblock_free_all(); 169 170 print_vm_layout(); 171 } 172 173 /* Limit the memory size via mem. */ 174 static phys_addr_t memory_limit; 175 #ifdef CONFIG_XIP_KERNEL 176 #define memory_limit (*(phys_addr_t *)XIP_FIXUP(&memory_limit)) 177 #endif /* CONFIG_XIP_KERNEL */ 178 179 static int __init early_mem(char *p) 180 { 181 u64 size; 182 183 if (!p) 184 return 1; 185 186 size = memparse(p, &p) & PAGE_MASK; 187 memory_limit = min_t(u64, size, memory_limit); 188 189 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20); 190 191 return 0; 192 } 193 early_param("mem", early_mem); 194 195 static void __init setup_bootmem(void) 196 { 197 phys_addr_t vmlinux_end = __pa_symbol(&_end); 198 phys_addr_t max_mapped_addr; 199 phys_addr_t phys_ram_end, vmlinux_start; 200 201 if (IS_ENABLED(CONFIG_XIP_KERNEL)) 202 vmlinux_start = __pa_symbol(&_sdata); 203 else 204 vmlinux_start = __pa_symbol(&_start); 205 206 memblock_enforce_memory_limit(memory_limit); 207 208 /* 209 * Make sure we align the reservation on PMD_SIZE since we will 210 * map the kernel in the linear mapping as read-only: we do not want 211 * any allocation to happen between _end and the next pmd aligned page. 212 */ 213 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) 214 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK; 215 /* 216 * Reserve from the start of the kernel to the end of the kernel 217 */ 218 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); 219 220 /* 221 * Make sure we align the start of the memory on a PMD boundary so that 222 * at worst, we map the linear mapping with PMD mappings. 223 */ 224 if (!IS_ENABLED(CONFIG_XIP_KERNEL)) 225 phys_ram_base = memblock_start_of_DRAM() & PMD_MASK; 226 227 /* 228 * In 64-bit, any use of __va/__pa before this point is wrong as we 229 * did not know the start of DRAM before. 230 */ 231 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_MMU)) 232 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; 233 234 /* 235 * The size of the linear page mapping may restrict the amount of 236 * usable RAM. 237 */ 238 if (IS_ENABLED(CONFIG_64BIT)) { 239 max_mapped_addr = __pa(PAGE_OFFSET) + KERN_VIRT_SIZE; 240 memblock_cap_memory_range(phys_ram_base, 241 max_mapped_addr - phys_ram_base); 242 } 243 244 /* 245 * Reserve physical address space that would be mapped to virtual 246 * addresses greater than (void *)(-PAGE_SIZE) because: 247 * - This memory would overlap with ERR_PTR 248 * - This memory belongs to high memory, which is not supported 249 * 250 * This is not applicable to 64-bit kernel, because virtual addresses 251 * after (void *)(-PAGE_SIZE) are not linearly mapped: they are 252 * occupied by kernel mapping. Also it is unrealistic for high memory 253 * to exist on 64-bit platforms. 254 */ 255 if (!IS_ENABLED(CONFIG_64BIT)) { 256 max_mapped_addr = __va_to_pa_nodebug(-PAGE_SIZE); 257 memblock_reserve(max_mapped_addr, (phys_addr_t)-max_mapped_addr); 258 } 259 260 phys_ram_end = memblock_end_of_DRAM(); 261 min_low_pfn = PFN_UP(phys_ram_base); 262 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); 263 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn))); 264 265 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn)); 266 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET); 267 268 reserve_initrd_mem(); 269 270 /* 271 * No allocation should be done before reserving the memory as defined 272 * in the device tree, otherwise the allocation could end up in a 273 * reserved region. 274 */ 275 early_init_fdt_scan_reserved_mem(); 276 277 /* 278 * If DTB is built in, no need to reserve its memblock. 279 * Otherwise, do reserve it but avoid using 280 * early_init_fdt_reserve_self() since __pa() does 281 * not work for DTB pointers that are fixmap addresses 282 */ 283 if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) 284 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); 285 286 dma_contiguous_reserve(dma32_phys_limit); 287 if (IS_ENABLED(CONFIG_64BIT)) 288 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); 289 } 290 291 #ifdef CONFIG_MMU 292 struct pt_alloc_ops pt_ops __initdata; 293 294 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 295 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 296 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; 297 298 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 299 300 #ifdef CONFIG_XIP_KERNEL 301 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops)) 302 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir)) 303 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte)) 304 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir)) 305 #endif /* CONFIG_XIP_KERNEL */ 306 307 static const pgprot_t protection_map[16] = { 308 [VM_NONE] = PAGE_NONE, 309 [VM_READ] = PAGE_READ, 310 [VM_WRITE] = PAGE_COPY, 311 [VM_WRITE | VM_READ] = PAGE_COPY, 312 [VM_EXEC] = PAGE_EXEC, 313 [VM_EXEC | VM_READ] = PAGE_READ_EXEC, 314 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC, 315 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC, 316 [VM_SHARED] = PAGE_NONE, 317 [VM_SHARED | VM_READ] = PAGE_READ, 318 [VM_SHARED | VM_WRITE] = PAGE_SHARED, 319 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, 320 [VM_SHARED | VM_EXEC] = PAGE_EXEC, 321 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC, 322 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC, 323 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC 324 }; 325 DECLARE_VM_GET_PAGE_PROT 326 327 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) 328 { 329 unsigned long addr = __fix_to_virt(idx); 330 pte_t *ptep; 331 332 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); 333 334 ptep = &fixmap_pte[pte_index(addr)]; 335 336 if (pgprot_val(prot)) 337 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot)); 338 else 339 pte_clear(&init_mm, addr, ptep); 340 local_flush_tlb_page(addr); 341 } 342 343 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa) 344 { 345 return (pte_t *)((uintptr_t)pa); 346 } 347 348 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa) 349 { 350 clear_fixmap(FIX_PTE); 351 return (pte_t *)set_fixmap_offset(FIX_PTE, pa); 352 } 353 354 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa) 355 { 356 return (pte_t *) __va(pa); 357 } 358 359 static inline phys_addr_t __init alloc_pte_early(uintptr_t va) 360 { 361 /* 362 * We only create PMD or PGD early mappings so we 363 * should never reach here with MMU disabled. 364 */ 365 BUG(); 366 } 367 368 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va) 369 { 370 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 371 } 372 373 static phys_addr_t __init alloc_pte_late(uintptr_t va) 374 { 375 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 376 377 BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc)); 378 return __pa((pte_t *)ptdesc_address(ptdesc)); 379 } 380 381 static void __init create_pte_mapping(pte_t *ptep, 382 uintptr_t va, phys_addr_t pa, 383 phys_addr_t sz, pgprot_t prot) 384 { 385 uintptr_t pte_idx = pte_index(va); 386 387 BUG_ON(sz != PAGE_SIZE); 388 389 if (pte_none(ptep[pte_idx])) 390 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot); 391 } 392 393 #ifndef __PAGETABLE_PMD_FOLDED 394 395 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss; 396 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; 397 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); 398 399 #ifdef CONFIG_XIP_KERNEL 400 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd)) 401 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd)) 402 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd)) 403 #endif /* CONFIG_XIP_KERNEL */ 404 405 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss; 406 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss; 407 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); 408 409 #ifdef CONFIG_XIP_KERNEL 410 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d)) 411 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d)) 412 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d)) 413 #endif /* CONFIG_XIP_KERNEL */ 414 415 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; 416 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; 417 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); 418 419 #ifdef CONFIG_XIP_KERNEL 420 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud)) 421 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud)) 422 #define early_pud ((pud_t *)XIP_FIXUP(early_pud)) 423 #endif /* CONFIG_XIP_KERNEL */ 424 425 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) 426 { 427 /* Before MMU is enabled */ 428 return (pmd_t *)((uintptr_t)pa); 429 } 430 431 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa) 432 { 433 clear_fixmap(FIX_PMD); 434 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa); 435 } 436 437 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa) 438 { 439 return (pmd_t *) __va(pa); 440 } 441 442 static phys_addr_t __init alloc_pmd_early(uintptr_t va) 443 { 444 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); 445 446 return (uintptr_t)early_pmd; 447 } 448 449 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va) 450 { 451 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 452 } 453 454 static phys_addr_t __init alloc_pmd_late(uintptr_t va) 455 { 456 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 457 458 BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc)); 459 return __pa((pmd_t *)ptdesc_address(ptdesc)); 460 } 461 462 static void __init create_pmd_mapping(pmd_t *pmdp, 463 uintptr_t va, phys_addr_t pa, 464 phys_addr_t sz, pgprot_t prot) 465 { 466 pte_t *ptep; 467 phys_addr_t pte_phys; 468 uintptr_t pmd_idx = pmd_index(va); 469 470 if (sz == PMD_SIZE) { 471 if (pmd_none(pmdp[pmd_idx])) 472 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot); 473 return; 474 } 475 476 if (pmd_none(pmdp[pmd_idx])) { 477 pte_phys = pt_ops.alloc_pte(va); 478 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE); 479 ptep = pt_ops.get_pte_virt(pte_phys); 480 memset(ptep, 0, PAGE_SIZE); 481 } else { 482 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx])); 483 ptep = pt_ops.get_pte_virt(pte_phys); 484 } 485 486 create_pte_mapping(ptep, va, pa, sz, prot); 487 } 488 489 static pud_t *__init get_pud_virt_early(phys_addr_t pa) 490 { 491 return (pud_t *)((uintptr_t)pa); 492 } 493 494 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa) 495 { 496 clear_fixmap(FIX_PUD); 497 return (pud_t *)set_fixmap_offset(FIX_PUD, pa); 498 } 499 500 static pud_t *__init get_pud_virt_late(phys_addr_t pa) 501 { 502 return (pud_t *)__va(pa); 503 } 504 505 static phys_addr_t __init alloc_pud_early(uintptr_t va) 506 { 507 /* Only one PUD is available for early mapping */ 508 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 509 510 return (uintptr_t)early_pud; 511 } 512 513 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) 514 { 515 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 516 } 517 518 static phys_addr_t alloc_pud_late(uintptr_t va) 519 { 520 unsigned long vaddr; 521 522 vaddr = __get_free_page(GFP_KERNEL); 523 BUG_ON(!vaddr); 524 return __pa(vaddr); 525 } 526 527 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa) 528 { 529 return (p4d_t *)((uintptr_t)pa); 530 } 531 532 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa) 533 { 534 clear_fixmap(FIX_P4D); 535 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa); 536 } 537 538 static p4d_t *__init get_p4d_virt_late(phys_addr_t pa) 539 { 540 return (p4d_t *)__va(pa); 541 } 542 543 static phys_addr_t __init alloc_p4d_early(uintptr_t va) 544 { 545 /* Only one P4D is available for early mapping */ 546 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 547 548 return (uintptr_t)early_p4d; 549 } 550 551 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va) 552 { 553 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 554 } 555 556 static phys_addr_t alloc_p4d_late(uintptr_t va) 557 { 558 unsigned long vaddr; 559 560 vaddr = __get_free_page(GFP_KERNEL); 561 BUG_ON(!vaddr); 562 return __pa(vaddr); 563 } 564 565 static void __init create_pud_mapping(pud_t *pudp, 566 uintptr_t va, phys_addr_t pa, 567 phys_addr_t sz, pgprot_t prot) 568 { 569 pmd_t *nextp; 570 phys_addr_t next_phys; 571 uintptr_t pud_index = pud_index(va); 572 573 if (sz == PUD_SIZE) { 574 if (pud_val(pudp[pud_index]) == 0) 575 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot); 576 return; 577 } 578 579 if (pud_val(pudp[pud_index]) == 0) { 580 next_phys = pt_ops.alloc_pmd(va); 581 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE); 582 nextp = pt_ops.get_pmd_virt(next_phys); 583 memset(nextp, 0, PAGE_SIZE); 584 } else { 585 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index])); 586 nextp = pt_ops.get_pmd_virt(next_phys); 587 } 588 589 create_pmd_mapping(nextp, va, pa, sz, prot); 590 } 591 592 static void __init create_p4d_mapping(p4d_t *p4dp, 593 uintptr_t va, phys_addr_t pa, 594 phys_addr_t sz, pgprot_t prot) 595 { 596 pud_t *nextp; 597 phys_addr_t next_phys; 598 uintptr_t p4d_index = p4d_index(va); 599 600 if (sz == P4D_SIZE) { 601 if (p4d_val(p4dp[p4d_index]) == 0) 602 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot); 603 return; 604 } 605 606 if (p4d_val(p4dp[p4d_index]) == 0) { 607 next_phys = pt_ops.alloc_pud(va); 608 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE); 609 nextp = pt_ops.get_pud_virt(next_phys); 610 memset(nextp, 0, PAGE_SIZE); 611 } else { 612 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index])); 613 nextp = pt_ops.get_pud_virt(next_phys); 614 } 615 616 create_pud_mapping(nextp, va, pa, sz, prot); 617 } 618 619 #define pgd_next_t p4d_t 620 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \ 621 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \ 622 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va))) 623 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \ 624 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \ 625 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa))) 626 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 627 (pgtable_l5_enabled ? \ 628 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \ 629 (pgtable_l4_enabled ? \ 630 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \ 631 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot))) 632 #define fixmap_pgd_next (pgtable_l5_enabled ? \ 633 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \ 634 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd)) 635 #define trampoline_pgd_next (pgtable_l5_enabled ? \ 636 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \ 637 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd)) 638 #else 639 #define pgd_next_t pte_t 640 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va) 641 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa) 642 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 643 create_pte_mapping(__nextp, __va, __pa, __sz, __prot) 644 #define fixmap_pgd_next ((uintptr_t)fixmap_pte) 645 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 646 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 647 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 648 #endif /* __PAGETABLE_PMD_FOLDED */ 649 650 void __init create_pgd_mapping(pgd_t *pgdp, 651 uintptr_t va, phys_addr_t pa, 652 phys_addr_t sz, pgprot_t prot) 653 { 654 pgd_next_t *nextp; 655 phys_addr_t next_phys; 656 uintptr_t pgd_idx = pgd_index(va); 657 658 if (sz == PGDIR_SIZE) { 659 if (pgd_val(pgdp[pgd_idx]) == 0) 660 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot); 661 return; 662 } 663 664 if (pgd_val(pgdp[pgd_idx]) == 0) { 665 next_phys = alloc_pgd_next(va); 666 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE); 667 nextp = get_pgd_next_virt(next_phys); 668 memset(nextp, 0, PAGE_SIZE); 669 } else { 670 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx])); 671 nextp = get_pgd_next_virt(next_phys); 672 } 673 674 create_pgd_next_mapping(nextp, va, pa, sz, prot); 675 } 676 677 static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va, 678 phys_addr_t size) 679 { 680 if (debug_pagealloc_enabled()) 681 return PAGE_SIZE; 682 683 if (pgtable_l5_enabled && 684 !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE) 685 return P4D_SIZE; 686 687 if (pgtable_l4_enabled && 688 !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE) 689 return PUD_SIZE; 690 691 if (IS_ENABLED(CONFIG_64BIT) && 692 !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE) 693 return PMD_SIZE; 694 695 return PAGE_SIZE; 696 } 697 698 #ifdef CONFIG_XIP_KERNEL 699 #define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base)) 700 extern char _xiprom[], _exiprom[], __data_loc; 701 702 /* called from head.S with MMU off */ 703 asmlinkage void __init __copy_data(void) 704 { 705 void *from = (void *)(&__data_loc); 706 void *to = (void *)CONFIG_PHYS_RAM_BASE; 707 size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata)); 708 709 memcpy(to, from, sz); 710 } 711 #endif 712 713 #ifdef CONFIG_STRICT_KERNEL_RWX 714 static __init pgprot_t pgprot_from_va(uintptr_t va) 715 { 716 if (is_va_kernel_text(va)) 717 return PAGE_KERNEL_READ_EXEC; 718 719 /* 720 * In 64-bit kernel, the kernel mapping is outside the linear mapping so 721 * we must protect its linear mapping alias from being executed and 722 * written. 723 * And rodata section is marked readonly in mark_rodata_ro. 724 */ 725 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va)) 726 return PAGE_KERNEL_READ; 727 728 return PAGE_KERNEL; 729 } 730 731 void mark_rodata_ro(void) 732 { 733 set_kernel_memory(__start_rodata, _data, set_memory_ro); 734 if (IS_ENABLED(CONFIG_64BIT)) 735 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data), 736 set_memory_ro); 737 738 debug_checkwx(); 739 } 740 #else 741 static __init pgprot_t pgprot_from_va(uintptr_t va) 742 { 743 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va)) 744 return PAGE_KERNEL; 745 746 return PAGE_KERNEL_EXEC; 747 } 748 #endif /* CONFIG_STRICT_KERNEL_RWX */ 749 750 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 751 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa); 752 753 static void __init disable_pgtable_l5(void) 754 { 755 pgtable_l5_enabled = false; 756 kernel_map.page_offset = PAGE_OFFSET_L4; 757 satp_mode = SATP_MODE_48; 758 } 759 760 static void __init disable_pgtable_l4(void) 761 { 762 pgtable_l4_enabled = false; 763 kernel_map.page_offset = PAGE_OFFSET_L3; 764 satp_mode = SATP_MODE_39; 765 } 766 767 static int __init print_no4lvl(char *p) 768 { 769 pr_info("Disabled 4-level and 5-level paging"); 770 return 0; 771 } 772 early_param("no4lvl", print_no4lvl); 773 774 static int __init print_no5lvl(char *p) 775 { 776 pr_info("Disabled 5-level paging"); 777 return 0; 778 } 779 early_param("no5lvl", print_no5lvl); 780 781 /* 782 * There is a simple way to determine if 4-level is supported by the 783 * underlying hardware: establish 1:1 mapping in 4-level page table mode 784 * then read SATP to see if the configuration was taken into account 785 * meaning sv48 is supported. 786 */ 787 static __init void set_satp_mode(uintptr_t dtb_pa) 788 { 789 u64 identity_satp, hw_satp; 790 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; 791 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa); 792 793 if (satp_mode_cmdline == SATP_MODE_57) { 794 disable_pgtable_l5(); 795 } else if (satp_mode_cmdline == SATP_MODE_48) { 796 disable_pgtable_l5(); 797 disable_pgtable_l4(); 798 return; 799 } 800 801 create_p4d_mapping(early_p4d, 802 set_satp_mode_pmd, (uintptr_t)early_pud, 803 P4D_SIZE, PAGE_TABLE); 804 create_pud_mapping(early_pud, 805 set_satp_mode_pmd, (uintptr_t)early_pmd, 806 PUD_SIZE, PAGE_TABLE); 807 /* Handle the case where set_satp_mode straddles 2 PMDs */ 808 create_pmd_mapping(early_pmd, 809 set_satp_mode_pmd, set_satp_mode_pmd, 810 PMD_SIZE, PAGE_KERNEL_EXEC); 811 create_pmd_mapping(early_pmd, 812 set_satp_mode_pmd + PMD_SIZE, 813 set_satp_mode_pmd + PMD_SIZE, 814 PMD_SIZE, PAGE_KERNEL_EXEC); 815 retry: 816 create_pgd_mapping(early_pg_dir, 817 set_satp_mode_pmd, 818 pgtable_l5_enabled ? 819 (uintptr_t)early_p4d : (uintptr_t)early_pud, 820 PGDIR_SIZE, PAGE_TABLE); 821 822 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; 823 824 local_flush_tlb_all(); 825 csr_write(CSR_SATP, identity_satp); 826 hw_satp = csr_swap(CSR_SATP, 0ULL); 827 local_flush_tlb_all(); 828 829 if (hw_satp != identity_satp) { 830 if (pgtable_l5_enabled) { 831 disable_pgtable_l5(); 832 memset(early_pg_dir, 0, PAGE_SIZE); 833 goto retry; 834 } 835 disable_pgtable_l4(); 836 } 837 838 memset(early_pg_dir, 0, PAGE_SIZE); 839 memset(early_p4d, 0, PAGE_SIZE); 840 memset(early_pud, 0, PAGE_SIZE); 841 memset(early_pmd, 0, PAGE_SIZE); 842 } 843 #endif 844 845 /* 846 * setup_vm() is called from head.S with MMU-off. 847 * 848 * Following requirements should be honoured for setup_vm() to work 849 * correctly: 850 * 1) It should use PC-relative addressing for accessing kernel symbols. 851 * To achieve this we always use GCC cmodel=medany. 852 * 2) The compiler instrumentation for FTRACE will not work for setup_vm() 853 * so disable compiler instrumentation when FTRACE is enabled. 854 * 855 * Currently, the above requirements are honoured by using custom CFLAGS 856 * for init.o in mm/Makefile. 857 */ 858 859 #ifndef __riscv_cmodel_medany 860 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing." 861 #endif 862 863 #ifdef CONFIG_RELOCATABLE 864 extern unsigned long __rela_dyn_start, __rela_dyn_end; 865 866 static void __init relocate_kernel(void) 867 { 868 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start; 869 /* 870 * This holds the offset between the linked virtual address and the 871 * relocated virtual address. 872 */ 873 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR; 874 /* 875 * This holds the offset between kernel linked virtual address and 876 * physical address. 877 */ 878 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr; 879 880 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) { 881 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset); 882 Elf64_Addr relocated_addr = rela->r_addend; 883 884 if (rela->r_info != R_RISCV_RELATIVE) 885 continue; 886 887 /* 888 * Make sure to not relocate vdso symbols like rt_sigreturn 889 * which are linked from the address 0 in vmlinux since 890 * vdso symbol addresses are actually used as an offset from 891 * mm->context.vdso in VDSO_OFFSET macro. 892 */ 893 if (relocated_addr >= KERNEL_LINK_ADDR) 894 relocated_addr += reloc_offset; 895 896 *(Elf64_Addr *)addr = relocated_addr; 897 } 898 } 899 #endif /* CONFIG_RELOCATABLE */ 900 901 #ifdef CONFIG_XIP_KERNEL 902 static void __init create_kernel_page_table(pgd_t *pgdir, 903 __always_unused bool early) 904 { 905 uintptr_t va, end_va; 906 907 /* Map the flash resident part */ 908 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz; 909 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 910 create_pgd_mapping(pgdir, va, 911 kernel_map.xiprom + (va - kernel_map.virt_addr), 912 PMD_SIZE, PAGE_KERNEL_EXEC); 913 914 /* Map the data in RAM */ 915 end_va = kernel_map.virt_addr + kernel_map.size; 916 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) 917 create_pgd_mapping(pgdir, va, 918 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), 919 PMD_SIZE, PAGE_KERNEL); 920 } 921 #else 922 static void __init create_kernel_page_table(pgd_t *pgdir, bool early) 923 { 924 uintptr_t va, end_va; 925 926 end_va = kernel_map.virt_addr + kernel_map.size; 927 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 928 create_pgd_mapping(pgdir, va, 929 kernel_map.phys_addr + (va - kernel_map.virt_addr), 930 PMD_SIZE, 931 early ? 932 PAGE_KERNEL_EXEC : pgprot_from_va(va)); 933 } 934 #endif 935 936 /* 937 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel, 938 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR 939 * entry. 940 */ 941 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va, 942 uintptr_t dtb_pa) 943 { 944 #ifndef CONFIG_BUILTIN_DTB 945 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); 946 947 /* Make sure the fdt fixmap address is always aligned on PMD size */ 948 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE)); 949 950 /* In 32-bit only, the fdt lies in its own PGD */ 951 if (!IS_ENABLED(CONFIG_64BIT)) { 952 create_pgd_mapping(early_pg_dir, fix_fdt_va, 953 pa, MAX_FDT_SIZE, PAGE_KERNEL); 954 } else { 955 create_pmd_mapping(fixmap_pmd, fix_fdt_va, 956 pa, PMD_SIZE, PAGE_KERNEL); 957 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE, 958 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); 959 } 960 961 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1)); 962 #else 963 /* 964 * For 64-bit kernel, __va can't be used since it would return a linear 965 * mapping address whereas dtb_early_va will be used before 966 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the 967 * kernel is mapped in the linear mapping, that makes no difference. 968 */ 969 dtb_early_va = kernel_mapping_pa_to_va(dtb_pa); 970 #endif 971 972 dtb_early_pa = dtb_pa; 973 } 974 975 /* 976 * MMU is not enabled, the page tables are allocated directly using 977 * early_pmd/pud/p4d and the address returned is the physical one. 978 */ 979 static void __init pt_ops_set_early(void) 980 { 981 pt_ops.alloc_pte = alloc_pte_early; 982 pt_ops.get_pte_virt = get_pte_virt_early; 983 #ifndef __PAGETABLE_PMD_FOLDED 984 pt_ops.alloc_pmd = alloc_pmd_early; 985 pt_ops.get_pmd_virt = get_pmd_virt_early; 986 pt_ops.alloc_pud = alloc_pud_early; 987 pt_ops.get_pud_virt = get_pud_virt_early; 988 pt_ops.alloc_p4d = alloc_p4d_early; 989 pt_ops.get_p4d_virt = get_p4d_virt_early; 990 #endif 991 } 992 993 /* 994 * MMU is enabled but page table setup is not complete yet. 995 * fixmap page table alloc functions must be used as a means to temporarily 996 * map the allocated physical pages since the linear mapping does not exist yet. 997 * 998 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va, 999 * but it will be used as described above. 1000 */ 1001 static void __init pt_ops_set_fixmap(void) 1002 { 1003 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap); 1004 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap); 1005 #ifndef __PAGETABLE_PMD_FOLDED 1006 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap); 1007 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap); 1008 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap); 1009 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap); 1010 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap); 1011 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap); 1012 #endif 1013 } 1014 1015 /* 1016 * MMU is enabled and page table setup is complete, so from now, we can use 1017 * generic page allocation functions to setup page table. 1018 */ 1019 static void __init pt_ops_set_late(void) 1020 { 1021 pt_ops.alloc_pte = alloc_pte_late; 1022 pt_ops.get_pte_virt = get_pte_virt_late; 1023 #ifndef __PAGETABLE_PMD_FOLDED 1024 pt_ops.alloc_pmd = alloc_pmd_late; 1025 pt_ops.get_pmd_virt = get_pmd_virt_late; 1026 pt_ops.alloc_pud = alloc_pud_late; 1027 pt_ops.get_pud_virt = get_pud_virt_late; 1028 pt_ops.alloc_p4d = alloc_p4d_late; 1029 pt_ops.get_p4d_virt = get_p4d_virt_late; 1030 #endif 1031 } 1032 1033 #ifdef CONFIG_RANDOMIZE_BASE 1034 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa); 1035 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa); 1036 1037 static int __init print_nokaslr(char *p) 1038 { 1039 pr_info("Disabled KASLR"); 1040 return 0; 1041 } 1042 early_param("nokaslr", print_nokaslr); 1043 1044 unsigned long kaslr_offset(void) 1045 { 1046 return kernel_map.virt_offset; 1047 } 1048 #endif 1049 1050 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1051 { 1052 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1053 1054 #ifdef CONFIG_RANDOMIZE_BASE 1055 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) { 1056 u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa); 1057 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start); 1058 u32 nr_pos; 1059 1060 /* 1061 * Compute the number of positions available: we are limited 1062 * by the early page table that only has one PUD and we must 1063 * be aligned on PMD_SIZE. 1064 */ 1065 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE; 1066 1067 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE; 1068 } 1069 #endif 1070 1071 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset; 1072 1073 #ifdef CONFIG_XIP_KERNEL 1074 #ifdef CONFIG_64BIT 1075 kernel_map.page_offset = PAGE_OFFSET_L3; 1076 #else 1077 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1078 #endif 1079 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; 1080 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); 1081 1082 phys_ram_base = CONFIG_PHYS_RAM_BASE; 1083 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; 1084 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_start); 1085 1086 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; 1087 #else 1088 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1089 kernel_map.phys_addr = (uintptr_t)(&_start); 1090 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1091 #endif 1092 1093 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 1094 set_satp_mode(dtb_pa); 1095 #endif 1096 1097 /* 1098 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1099 * where we have the system memory layout: this allows us to align 1100 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1101 * for the linear mapping. This is only possible because the kernel 1102 * mapping lies outside the linear mapping. 1103 * In 32-bit however, as the kernel resides in the linear mapping, 1104 * setup_vm_final can not change the mapping established here, 1105 * otherwise the same kernel addresses would get mapped to different 1106 * physical addresses (if the start of dram is different from the 1107 * kernel physical address start). 1108 */ 1109 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1110 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1111 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1112 1113 /* 1114 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit 1115 * kernel, whereas for 64-bit kernel, the end of the virtual address 1116 * space is occupied by the modules/BPF/kernel mappings which reduces 1117 * the available size of the linear mapping. 1118 */ 1119 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); 1120 1121 /* Sanity check alignment and size */ 1122 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1123 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1124 1125 #ifdef CONFIG_64BIT 1126 /* 1127 * The last 4K bytes of the addressable memory can not be mapped because 1128 * of IS_ERR_VALUE macro. 1129 */ 1130 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1131 #endif 1132 1133 #ifdef CONFIG_RELOCATABLE 1134 /* 1135 * Early page table uses only one PUD, which makes it possible 1136 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1137 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1138 * since a part of the kernel would not get mapped. 1139 */ 1140 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1141 relocate_kernel(); 1142 #endif 1143 1144 apply_early_boot_alternatives(); 1145 pt_ops_set_early(); 1146 1147 /* Setup early PGD for fixmap */ 1148 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1149 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1150 1151 #ifndef __PAGETABLE_PMD_FOLDED 1152 /* Setup fixmap P4D and PUD */ 1153 if (pgtable_l5_enabled) 1154 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1155 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1156 /* Setup fixmap PUD and PMD */ 1157 if (pgtable_l4_enabled) 1158 create_pud_mapping(fixmap_pud, FIXADDR_START, 1159 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1160 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1161 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1162 /* Setup trampoline PGD and PMD */ 1163 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1164 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1165 if (pgtable_l5_enabled) 1166 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1167 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1168 if (pgtable_l4_enabled) 1169 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1170 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1171 #ifdef CONFIG_XIP_KERNEL 1172 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1173 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); 1174 #else 1175 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1176 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1177 #endif 1178 #else 1179 /* Setup trampoline PGD */ 1180 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1181 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1182 #endif 1183 1184 /* 1185 * Setup early PGD covering entire kernel which will allow 1186 * us to reach paging_init(). We map all memory banks later 1187 * in setup_vm_final() below. 1188 */ 1189 create_kernel_page_table(early_pg_dir, true); 1190 1191 /* Setup early mapping for FDT early scan */ 1192 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1193 1194 /* 1195 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1196 * range can not span multiple pmds. 1197 */ 1198 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1199 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1200 1201 #ifndef __PAGETABLE_PMD_FOLDED 1202 /* 1203 * Early ioremap fixmap is already created as it lies within first 2MB 1204 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1205 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1206 * the user if not. 1207 */ 1208 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1209 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1210 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1211 WARN_ON(1); 1212 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1213 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1214 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1215 fix_to_virt(FIX_BTMAP_BEGIN)); 1216 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1217 fix_to_virt(FIX_BTMAP_END)); 1218 1219 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1220 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1221 } 1222 #endif 1223 1224 pt_ops_set_fixmap(); 1225 } 1226 1227 static void __init create_linear_mapping_range(phys_addr_t start, 1228 phys_addr_t end, 1229 uintptr_t fixed_map_size) 1230 { 1231 phys_addr_t pa; 1232 uintptr_t va, map_size; 1233 1234 for (pa = start; pa < end; pa += map_size) { 1235 va = (uintptr_t)__va(pa); 1236 map_size = fixed_map_size ? fixed_map_size : 1237 best_map_size(pa, va, end - pa); 1238 1239 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1240 pgprot_from_va(va)); 1241 } 1242 } 1243 1244 static void __init create_linear_mapping_page_table(void) 1245 { 1246 phys_addr_t start, end; 1247 phys_addr_t kfence_pool __maybe_unused; 1248 u64 i; 1249 1250 #ifdef CONFIG_STRICT_KERNEL_RWX 1251 phys_addr_t ktext_start = __pa_symbol(_start); 1252 phys_addr_t ktext_size = __init_data_begin - _start; 1253 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1254 phys_addr_t krodata_size = _data - __start_rodata; 1255 1256 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1257 memblock_mark_nomap(ktext_start, ktext_size); 1258 memblock_mark_nomap(krodata_start, krodata_size); 1259 #endif 1260 1261 #ifdef CONFIG_KFENCE 1262 /* 1263 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1264 * before we setup the linear mapping so that we avoid using hugepages 1265 * for this region. 1266 */ 1267 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1268 BUG_ON(!kfence_pool); 1269 1270 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1271 __kfence_pool = __va(kfence_pool); 1272 #endif 1273 1274 /* Map all memory banks in the linear mapping */ 1275 for_each_mem_range(i, &start, &end) { 1276 if (start >= end) 1277 break; 1278 if (start <= __pa(PAGE_OFFSET) && 1279 __pa(PAGE_OFFSET) < end) 1280 start = __pa(PAGE_OFFSET); 1281 1282 create_linear_mapping_range(start, end, 0); 1283 } 1284 1285 #ifdef CONFIG_STRICT_KERNEL_RWX 1286 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0); 1287 create_linear_mapping_range(krodata_start, 1288 krodata_start + krodata_size, 0); 1289 1290 memblock_clear_nomap(ktext_start, ktext_size); 1291 memblock_clear_nomap(krodata_start, krodata_size); 1292 #endif 1293 1294 #ifdef CONFIG_KFENCE 1295 create_linear_mapping_range(kfence_pool, 1296 kfence_pool + KFENCE_POOL_SIZE, 1297 PAGE_SIZE); 1298 1299 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1300 #endif 1301 } 1302 1303 static void __init setup_vm_final(void) 1304 { 1305 /* Setup swapper PGD for fixmap */ 1306 #if !defined(CONFIG_64BIT) 1307 /* 1308 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1309 * directly in swapper_pg_dir in addition to the pgd entry that points 1310 * to fixmap_pte. 1311 */ 1312 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1313 1314 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1315 #endif 1316 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1317 __pa_symbol(fixmap_pgd_next), 1318 PGDIR_SIZE, PAGE_TABLE); 1319 1320 /* Map the linear mapping */ 1321 create_linear_mapping_page_table(); 1322 1323 /* Map the kernel */ 1324 if (IS_ENABLED(CONFIG_64BIT)) 1325 create_kernel_page_table(swapper_pg_dir, false); 1326 1327 #ifdef CONFIG_KASAN 1328 kasan_swapper_init(); 1329 #endif 1330 1331 /* Clear fixmap PTE and PMD mappings */ 1332 clear_fixmap(FIX_PTE); 1333 clear_fixmap(FIX_PMD); 1334 clear_fixmap(FIX_PUD); 1335 clear_fixmap(FIX_P4D); 1336 1337 /* Move to swapper page table */ 1338 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1339 local_flush_tlb_all(); 1340 1341 pt_ops_set_late(); 1342 } 1343 #else 1344 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1345 { 1346 dtb_early_va = (void *)dtb_pa; 1347 dtb_early_pa = dtb_pa; 1348 } 1349 1350 static inline void setup_vm_final(void) 1351 { 1352 } 1353 #endif /* CONFIG_MMU */ 1354 1355 /* Reserve 128M low memory by default for swiotlb buffer */ 1356 #define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20) 1357 1358 static int __init reserve_crashkernel_low(unsigned long long low_size) 1359 { 1360 unsigned long long low_base; 1361 1362 low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit); 1363 if (!low_base) { 1364 pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size); 1365 return -ENOMEM; 1366 } 1367 1368 pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n", 1369 low_base, low_base + low_size, low_size >> 20); 1370 1371 crashk_low_res.start = low_base; 1372 crashk_low_res.end = low_base + low_size - 1; 1373 1374 return 0; 1375 } 1376 1377 /* 1378 * reserve_crashkernel() - reserves memory for crash kernel 1379 * 1380 * This function reserves memory area given in "crashkernel=" kernel command 1381 * line parameter. The memory reserved is used by dump capture kernel when 1382 * primary kernel is crashing. 1383 */ 1384 static void __init reserve_crashkernel(void) 1385 { 1386 unsigned long long crash_base = 0; 1387 unsigned long long crash_size = 0; 1388 unsigned long long crash_low_size = 0; 1389 unsigned long search_start = memblock_start_of_DRAM(); 1390 unsigned long search_end = (unsigned long)dma32_phys_limit; 1391 char *cmdline = boot_command_line; 1392 bool fixed_base = false; 1393 bool high = false; 1394 1395 int ret = 0; 1396 1397 if (!IS_ENABLED(CONFIG_KEXEC_CORE)) 1398 return; 1399 /* 1400 * Don't reserve a region for a crash kernel on a crash kernel 1401 * since it doesn't make much sense and we have limited memory 1402 * resources. 1403 */ 1404 if (is_kdump_kernel()) { 1405 pr_info("crashkernel: ignoring reservation request\n"); 1406 return; 1407 } 1408 1409 ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), 1410 &crash_size, &crash_base); 1411 if (ret == -ENOENT) { 1412 /* Fallback to crashkernel=X,[high,low] */ 1413 ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base); 1414 if (ret || !crash_size) 1415 return; 1416 1417 /* 1418 * crashkernel=Y,low is valid only when crashkernel=X,high 1419 * is passed. 1420 */ 1421 ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base); 1422 if (ret == -ENOENT) 1423 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; 1424 else if (ret) 1425 return; 1426 1427 search_start = (unsigned long)dma32_phys_limit; 1428 search_end = memblock_end_of_DRAM(); 1429 high = true; 1430 } else if (ret || !crash_size) { 1431 /* Invalid argument value specified */ 1432 return; 1433 } 1434 1435 crash_size = PAGE_ALIGN(crash_size); 1436 1437 if (crash_base) { 1438 fixed_base = true; 1439 search_start = crash_base; 1440 search_end = crash_base + crash_size; 1441 } 1442 1443 /* 1444 * Current riscv boot protocol requires 2MB alignment for 1445 * RV64 and 4MB alignment for RV32 (hugepage size) 1446 * 1447 * Try to alloc from 32bit addressible physical memory so that 1448 * swiotlb can work on the crash kernel. 1449 */ 1450 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1451 search_start, search_end); 1452 if (crash_base == 0) { 1453 /* 1454 * For crashkernel=size[KMG]@offset[KMG], print out failure 1455 * message if can't reserve the specified region. 1456 */ 1457 if (fixed_base) { 1458 pr_warn("crashkernel: allocating failed with given size@offset\n"); 1459 return; 1460 } 1461 1462 if (high) { 1463 /* 1464 * For crashkernel=size[KMG],high, if the first attempt was 1465 * for high memory, fall back to low memory. 1466 */ 1467 search_start = memblock_start_of_DRAM(); 1468 search_end = (unsigned long)dma32_phys_limit; 1469 } else { 1470 /* 1471 * For crashkernel=size[KMG], if the first attempt was for 1472 * low memory, fall back to high memory, the minimum required 1473 * low memory will be reserved later. 1474 */ 1475 search_start = (unsigned long)dma32_phys_limit; 1476 search_end = memblock_end_of_DRAM(); 1477 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; 1478 } 1479 1480 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1481 search_start, search_end); 1482 if (crash_base == 0) { 1483 pr_warn("crashkernel: couldn't allocate %lldKB\n", 1484 crash_size >> 10); 1485 return; 1486 } 1487 } 1488 1489 if ((crash_base >= dma32_phys_limit) && crash_low_size && 1490 reserve_crashkernel_low(crash_low_size)) { 1491 memblock_phys_free(crash_base, crash_size); 1492 return; 1493 } 1494 1495 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", 1496 crash_base, crash_base + crash_size, crash_size >> 20); 1497 1498 crashk_res.start = crash_base; 1499 crashk_res.end = crash_base + crash_size - 1; 1500 } 1501 1502 void __init paging_init(void) 1503 { 1504 setup_bootmem(); 1505 setup_vm_final(); 1506 1507 /* Depend on that Linear Mapping is ready */ 1508 memblock_allow_resize(); 1509 } 1510 1511 void __init misc_mem_init(void) 1512 { 1513 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1514 arch_numa_init(); 1515 sparse_init(); 1516 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1517 /* The entire VMEMMAP region has been populated. Flush TLB for this region */ 1518 local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); 1519 #endif 1520 zone_sizes_init(); 1521 reserve_crashkernel(); 1522 memblock_dump_all(); 1523 } 1524 1525 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1526 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1527 struct vmem_altmap *altmap) 1528 { 1529 return vmemmap_populate_basepages(start, end, node, NULL); 1530 } 1531 #endif 1532 1533 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1534 /* 1535 * Pre-allocates page-table pages for a specific area in the kernel 1536 * page-table. Only the level which needs to be synchronized between 1537 * all page-tables is allocated because the synchronization can be 1538 * expensive. 1539 */ 1540 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1541 const char *area) 1542 { 1543 unsigned long addr; 1544 const char *lvl; 1545 1546 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1547 pgd_t *pgd = pgd_offset_k(addr); 1548 p4d_t *p4d; 1549 pud_t *pud; 1550 pmd_t *pmd; 1551 1552 lvl = "p4d"; 1553 p4d = p4d_alloc(&init_mm, pgd, addr); 1554 if (!p4d) 1555 goto failed; 1556 1557 if (pgtable_l5_enabled) 1558 continue; 1559 1560 lvl = "pud"; 1561 pud = pud_alloc(&init_mm, p4d, addr); 1562 if (!pud) 1563 goto failed; 1564 1565 if (pgtable_l4_enabled) 1566 continue; 1567 1568 lvl = "pmd"; 1569 pmd = pmd_alloc(&init_mm, pud, addr); 1570 if (!pmd) 1571 goto failed; 1572 } 1573 return; 1574 1575 failed: 1576 /* 1577 * The pages have to be there now or they will be missing in 1578 * process page-tables later. 1579 */ 1580 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1581 } 1582 1583 void __init pgtable_cache_init(void) 1584 { 1585 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1586 if (IS_ENABLED(CONFIG_MODULES)) 1587 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1588 } 1589 #endif 1590