1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Regents of the University of California 4 * Copyright (C) 2019 Western Digital Corporation or its affiliates. 5 * Copyright (C) 2020 FORTH-ICS/CARV 6 * Nick Kossifidis <mick@ics.forth.gr> 7 */ 8 9 #include <linux/init.h> 10 #include <linux/mm.h> 11 #include <linux/memblock.h> 12 #include <linux/initrd.h> 13 #include <linux/swap.h> 14 #include <linux/swiotlb.h> 15 #include <linux/sizes.h> 16 #include <linux/of_fdt.h> 17 #include <linux/of_reserved_mem.h> 18 #include <linux/libfdt.h> 19 #include <linux/set_memory.h> 20 #include <linux/dma-map-ops.h> 21 #include <linux/crash_dump.h> 22 #include <linux/hugetlb.h> 23 #ifdef CONFIG_RELOCATABLE 24 #include <linux/elf.h> 25 #endif 26 #include <linux/kfence.h> 27 28 #include <asm/fixmap.h> 29 #include <asm/io.h> 30 #include <asm/numa.h> 31 #include <asm/pgtable.h> 32 #include <asm/sections.h> 33 #include <asm/soc.h> 34 #include <asm/tlbflush.h> 35 36 #include "../kernel/head.h" 37 38 struct kernel_mapping kernel_map __ro_after_init; 39 EXPORT_SYMBOL(kernel_map); 40 #ifdef CONFIG_XIP_KERNEL 41 #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map)) 42 #endif 43 44 #ifdef CONFIG_64BIT 45 u64 satp_mode __ro_after_init = !IS_ENABLED(CONFIG_XIP_KERNEL) ? SATP_MODE_57 : SATP_MODE_39; 46 #else 47 u64 satp_mode __ro_after_init = SATP_MODE_32; 48 #endif 49 EXPORT_SYMBOL(satp_mode); 50 51 #ifdef CONFIG_64BIT 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 #endif 57 58 phys_addr_t phys_ram_base __ro_after_init; 59 EXPORT_SYMBOL(phys_ram_base); 60 61 unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] 62 __page_aligned_bss; 63 EXPORT_SYMBOL(empty_zero_page); 64 65 extern char _start[]; 66 void *_dtb_early_va __initdata; 67 uintptr_t _dtb_early_pa __initdata; 68 69 phys_addr_t dma32_phys_limit __initdata; 70 71 static void __init zone_sizes_init(void) 72 { 73 unsigned long max_zone_pfns[MAX_NR_ZONES] = { 0, }; 74 75 #ifdef CONFIG_ZONE_DMA32 76 max_zone_pfns[ZONE_DMA32] = PFN_DOWN(dma32_phys_limit); 77 #endif 78 max_zone_pfns[ZONE_NORMAL] = max_low_pfn; 79 80 free_area_init(max_zone_pfns); 81 } 82 83 #if defined(CONFIG_MMU) && defined(CONFIG_DEBUG_VM) 84 85 #define LOG2_SZ_1K ilog2(SZ_1K) 86 #define LOG2_SZ_1M ilog2(SZ_1M) 87 #define LOG2_SZ_1G ilog2(SZ_1G) 88 #define LOG2_SZ_1T ilog2(SZ_1T) 89 90 static inline void print_mlk(char *name, unsigned long b, unsigned long t) 91 { 92 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld kB)\n", name, b, t, 93 (((t) - (b)) >> LOG2_SZ_1K)); 94 } 95 96 static inline void print_mlm(char *name, unsigned long b, unsigned long t) 97 { 98 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld MB)\n", name, b, t, 99 (((t) - (b)) >> LOG2_SZ_1M)); 100 } 101 102 static inline void print_mlg(char *name, unsigned long b, unsigned long t) 103 { 104 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld GB)\n", name, b, t, 105 (((t) - (b)) >> LOG2_SZ_1G)); 106 } 107 108 #ifdef CONFIG_64BIT 109 static inline void print_mlt(char *name, unsigned long b, unsigned long t) 110 { 111 pr_notice("%12s : 0x%08lx - 0x%08lx (%4ld TB)\n", name, b, t, 112 (((t) - (b)) >> LOG2_SZ_1T)); 113 } 114 #else 115 #define print_mlt(n, b, t) do {} while (0) 116 #endif 117 118 static inline void print_ml(char *name, unsigned long b, unsigned long t) 119 { 120 unsigned long diff = t - b; 121 122 if (IS_ENABLED(CONFIG_64BIT) && (diff >> LOG2_SZ_1T) >= 10) 123 print_mlt(name, b, t); 124 else if ((diff >> LOG2_SZ_1G) >= 10) 125 print_mlg(name, b, t); 126 else if ((diff >> LOG2_SZ_1M) >= 10) 127 print_mlm(name, b, t); 128 else 129 print_mlk(name, b, t); 130 } 131 132 static void __init print_vm_layout(void) 133 { 134 pr_notice("Virtual kernel memory layout:\n"); 135 print_ml("fixmap", (unsigned long)FIXADDR_START, 136 (unsigned long)FIXADDR_TOP); 137 print_ml("pci io", (unsigned long)PCI_IO_START, 138 (unsigned long)PCI_IO_END); 139 print_ml("vmemmap", (unsigned long)VMEMMAP_START, 140 (unsigned long)VMEMMAP_END); 141 print_ml("vmalloc", (unsigned long)VMALLOC_START, 142 (unsigned long)VMALLOC_END); 143 #ifdef CONFIG_64BIT 144 print_ml("modules", (unsigned long)MODULES_VADDR, 145 (unsigned long)MODULES_END); 146 #endif 147 print_ml("lowmem", (unsigned long)PAGE_OFFSET, 148 (unsigned long)high_memory); 149 if (IS_ENABLED(CONFIG_64BIT)) { 150 #ifdef CONFIG_KASAN 151 print_ml("kasan", KASAN_SHADOW_START, KASAN_SHADOW_END); 152 #endif 153 154 print_ml("kernel", (unsigned long)kernel_map.virt_addr, 155 (unsigned long)ADDRESS_SPACE_END); 156 } 157 } 158 #else 159 static void print_vm_layout(void) { } 160 #endif /* CONFIG_DEBUG_VM */ 161 162 void __init mem_init(void) 163 { 164 #ifdef CONFIG_FLATMEM 165 BUG_ON(!mem_map); 166 #endif /* CONFIG_FLATMEM */ 167 168 swiotlb_init(max_pfn > PFN_DOWN(dma32_phys_limit), SWIOTLB_VERBOSE); 169 memblock_free_all(); 170 171 print_vm_layout(); 172 } 173 174 /* Limit the memory size via mem. */ 175 static phys_addr_t memory_limit; 176 #ifdef CONFIG_XIP_KERNEL 177 #define memory_limit (*(phys_addr_t *)XIP_FIXUP(&memory_limit)) 178 #endif /* CONFIG_XIP_KERNEL */ 179 180 static int __init early_mem(char *p) 181 { 182 u64 size; 183 184 if (!p) 185 return 1; 186 187 size = memparse(p, &p) & PAGE_MASK; 188 memory_limit = min_t(u64, size, memory_limit); 189 190 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20); 191 192 return 0; 193 } 194 early_param("mem", early_mem); 195 196 static void __init setup_bootmem(void) 197 { 198 phys_addr_t vmlinux_end = __pa_symbol(&_end); 199 phys_addr_t max_mapped_addr; 200 phys_addr_t phys_ram_end, vmlinux_start; 201 202 if (IS_ENABLED(CONFIG_XIP_KERNEL)) 203 vmlinux_start = __pa_symbol(&_sdata); 204 else 205 vmlinux_start = __pa_symbol(&_start); 206 207 memblock_enforce_memory_limit(memory_limit); 208 209 /* 210 * Make sure we align the reservation on PMD_SIZE since we will 211 * map the kernel in the linear mapping as read-only: we do not want 212 * any allocation to happen between _end and the next pmd aligned page. 213 */ 214 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) 215 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK; 216 /* 217 * Reserve from the start of the kernel to the end of the kernel 218 */ 219 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); 220 221 phys_ram_end = memblock_end_of_DRAM(); 222 223 /* 224 * Make sure we align the start of the memory on a PMD boundary so that 225 * at worst, we map the linear mapping with PMD mappings. 226 */ 227 if (!IS_ENABLED(CONFIG_XIP_KERNEL)) 228 phys_ram_base = memblock_start_of_DRAM() & PMD_MASK; 229 230 /* 231 * In 64-bit, any use of __va/__pa before this point is wrong as we 232 * did not know the start of DRAM before. 233 */ 234 if (IS_ENABLED(CONFIG_64BIT)) 235 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; 236 237 /* 238 * memblock allocator is not aware of the fact that last 4K bytes of 239 * the addressable memory can not be mapped because of IS_ERR_VALUE 240 * macro. Make sure that last 4k bytes are not usable by memblock 241 * if end of dram is equal to maximum addressable memory. For 64-bit 242 * kernel, this problem can't happen here as the end of the virtual 243 * address space is occupied by the kernel mapping then this check must 244 * be done as soon as the kernel mapping base address is determined. 245 */ 246 if (!IS_ENABLED(CONFIG_64BIT)) { 247 max_mapped_addr = __pa(~(ulong)0); 248 if (max_mapped_addr == (phys_ram_end - 1)) 249 memblock_set_current_limit(max_mapped_addr - 4096); 250 } 251 252 min_low_pfn = PFN_UP(phys_ram_base); 253 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); 254 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn))); 255 256 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn)); 257 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET); 258 259 reserve_initrd_mem(); 260 261 /* 262 * No allocation should be done before reserving the memory as defined 263 * in the device tree, otherwise the allocation could end up in a 264 * reserved region. 265 */ 266 early_init_fdt_scan_reserved_mem(); 267 268 /* 269 * If DTB is built in, no need to reserve its memblock. 270 * Otherwise, do reserve it but avoid using 271 * early_init_fdt_reserve_self() since __pa() does 272 * not work for DTB pointers that are fixmap addresses 273 */ 274 if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) 275 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); 276 277 dma_contiguous_reserve(dma32_phys_limit); 278 if (IS_ENABLED(CONFIG_64BIT)) 279 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); 280 } 281 282 #ifdef CONFIG_MMU 283 struct pt_alloc_ops pt_ops __initdata; 284 285 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 286 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 287 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; 288 289 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 290 291 #ifdef CONFIG_XIP_KERNEL 292 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops)) 293 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir)) 294 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte)) 295 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir)) 296 #endif /* CONFIG_XIP_KERNEL */ 297 298 static const pgprot_t protection_map[16] = { 299 [VM_NONE] = PAGE_NONE, 300 [VM_READ] = PAGE_READ, 301 [VM_WRITE] = PAGE_COPY, 302 [VM_WRITE | VM_READ] = PAGE_COPY, 303 [VM_EXEC] = PAGE_EXEC, 304 [VM_EXEC | VM_READ] = PAGE_READ_EXEC, 305 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC, 306 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC, 307 [VM_SHARED] = PAGE_NONE, 308 [VM_SHARED | VM_READ] = PAGE_READ, 309 [VM_SHARED | VM_WRITE] = PAGE_SHARED, 310 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, 311 [VM_SHARED | VM_EXEC] = PAGE_EXEC, 312 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC, 313 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC, 314 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC 315 }; 316 DECLARE_VM_GET_PAGE_PROT 317 318 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) 319 { 320 unsigned long addr = __fix_to_virt(idx); 321 pte_t *ptep; 322 323 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); 324 325 ptep = &fixmap_pte[pte_index(addr)]; 326 327 if (pgprot_val(prot)) 328 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot)); 329 else 330 pte_clear(&init_mm, addr, ptep); 331 local_flush_tlb_page(addr); 332 } 333 334 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa) 335 { 336 return (pte_t *)((uintptr_t)pa); 337 } 338 339 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa) 340 { 341 clear_fixmap(FIX_PTE); 342 return (pte_t *)set_fixmap_offset(FIX_PTE, pa); 343 } 344 345 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa) 346 { 347 return (pte_t *) __va(pa); 348 } 349 350 static inline phys_addr_t __init alloc_pte_early(uintptr_t va) 351 { 352 /* 353 * We only create PMD or PGD early mappings so we 354 * should never reach here with MMU disabled. 355 */ 356 BUG(); 357 } 358 359 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va) 360 { 361 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 362 } 363 364 static phys_addr_t __init alloc_pte_late(uintptr_t va) 365 { 366 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 367 368 BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc)); 369 return __pa((pte_t *)ptdesc_address(ptdesc)); 370 } 371 372 static void __init create_pte_mapping(pte_t *ptep, 373 uintptr_t va, phys_addr_t pa, 374 phys_addr_t sz, pgprot_t prot) 375 { 376 uintptr_t pte_idx = pte_index(va); 377 378 BUG_ON(sz != PAGE_SIZE); 379 380 if (pte_none(ptep[pte_idx])) 381 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot); 382 } 383 384 #ifndef __PAGETABLE_PMD_FOLDED 385 386 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss; 387 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; 388 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); 389 390 #ifdef CONFIG_XIP_KERNEL 391 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd)) 392 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd)) 393 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd)) 394 #endif /* CONFIG_XIP_KERNEL */ 395 396 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss; 397 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss; 398 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); 399 400 #ifdef CONFIG_XIP_KERNEL 401 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d)) 402 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d)) 403 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d)) 404 #endif /* CONFIG_XIP_KERNEL */ 405 406 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; 407 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; 408 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); 409 410 #ifdef CONFIG_XIP_KERNEL 411 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud)) 412 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud)) 413 #define early_pud ((pud_t *)XIP_FIXUP(early_pud)) 414 #endif /* CONFIG_XIP_KERNEL */ 415 416 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) 417 { 418 /* Before MMU is enabled */ 419 return (pmd_t *)((uintptr_t)pa); 420 } 421 422 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa) 423 { 424 clear_fixmap(FIX_PMD); 425 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa); 426 } 427 428 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa) 429 { 430 return (pmd_t *) __va(pa); 431 } 432 433 static phys_addr_t __init alloc_pmd_early(uintptr_t va) 434 { 435 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); 436 437 return (uintptr_t)early_pmd; 438 } 439 440 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va) 441 { 442 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 443 } 444 445 static phys_addr_t __init alloc_pmd_late(uintptr_t va) 446 { 447 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 448 449 BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc)); 450 return __pa((pmd_t *)ptdesc_address(ptdesc)); 451 } 452 453 static void __init create_pmd_mapping(pmd_t *pmdp, 454 uintptr_t va, phys_addr_t pa, 455 phys_addr_t sz, pgprot_t prot) 456 { 457 pte_t *ptep; 458 phys_addr_t pte_phys; 459 uintptr_t pmd_idx = pmd_index(va); 460 461 if (sz == PMD_SIZE) { 462 if (pmd_none(pmdp[pmd_idx])) 463 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot); 464 return; 465 } 466 467 if (pmd_none(pmdp[pmd_idx])) { 468 pte_phys = pt_ops.alloc_pte(va); 469 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE); 470 ptep = pt_ops.get_pte_virt(pte_phys); 471 memset(ptep, 0, PAGE_SIZE); 472 } else { 473 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx])); 474 ptep = pt_ops.get_pte_virt(pte_phys); 475 } 476 477 create_pte_mapping(ptep, va, pa, sz, prot); 478 } 479 480 static pud_t *__init get_pud_virt_early(phys_addr_t pa) 481 { 482 return (pud_t *)((uintptr_t)pa); 483 } 484 485 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa) 486 { 487 clear_fixmap(FIX_PUD); 488 return (pud_t *)set_fixmap_offset(FIX_PUD, pa); 489 } 490 491 static pud_t *__init get_pud_virt_late(phys_addr_t pa) 492 { 493 return (pud_t *)__va(pa); 494 } 495 496 static phys_addr_t __init alloc_pud_early(uintptr_t va) 497 { 498 /* Only one PUD is available for early mapping */ 499 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 500 501 return (uintptr_t)early_pud; 502 } 503 504 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) 505 { 506 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 507 } 508 509 static phys_addr_t alloc_pud_late(uintptr_t va) 510 { 511 unsigned long vaddr; 512 513 vaddr = __get_free_page(GFP_KERNEL); 514 BUG_ON(!vaddr); 515 return __pa(vaddr); 516 } 517 518 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa) 519 { 520 return (p4d_t *)((uintptr_t)pa); 521 } 522 523 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa) 524 { 525 clear_fixmap(FIX_P4D); 526 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa); 527 } 528 529 static p4d_t *__init get_p4d_virt_late(phys_addr_t pa) 530 { 531 return (p4d_t *)__va(pa); 532 } 533 534 static phys_addr_t __init alloc_p4d_early(uintptr_t va) 535 { 536 /* Only one P4D is available for early mapping */ 537 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 538 539 return (uintptr_t)early_p4d; 540 } 541 542 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va) 543 { 544 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 545 } 546 547 static phys_addr_t alloc_p4d_late(uintptr_t va) 548 { 549 unsigned long vaddr; 550 551 vaddr = __get_free_page(GFP_KERNEL); 552 BUG_ON(!vaddr); 553 return __pa(vaddr); 554 } 555 556 static void __init create_pud_mapping(pud_t *pudp, 557 uintptr_t va, phys_addr_t pa, 558 phys_addr_t sz, pgprot_t prot) 559 { 560 pmd_t *nextp; 561 phys_addr_t next_phys; 562 uintptr_t pud_index = pud_index(va); 563 564 if (sz == PUD_SIZE) { 565 if (pud_val(pudp[pud_index]) == 0) 566 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot); 567 return; 568 } 569 570 if (pud_val(pudp[pud_index]) == 0) { 571 next_phys = pt_ops.alloc_pmd(va); 572 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE); 573 nextp = pt_ops.get_pmd_virt(next_phys); 574 memset(nextp, 0, PAGE_SIZE); 575 } else { 576 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index])); 577 nextp = pt_ops.get_pmd_virt(next_phys); 578 } 579 580 create_pmd_mapping(nextp, va, pa, sz, prot); 581 } 582 583 static void __init create_p4d_mapping(p4d_t *p4dp, 584 uintptr_t va, phys_addr_t pa, 585 phys_addr_t sz, pgprot_t prot) 586 { 587 pud_t *nextp; 588 phys_addr_t next_phys; 589 uintptr_t p4d_index = p4d_index(va); 590 591 if (sz == P4D_SIZE) { 592 if (p4d_val(p4dp[p4d_index]) == 0) 593 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot); 594 return; 595 } 596 597 if (p4d_val(p4dp[p4d_index]) == 0) { 598 next_phys = pt_ops.alloc_pud(va); 599 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE); 600 nextp = pt_ops.get_pud_virt(next_phys); 601 memset(nextp, 0, PAGE_SIZE); 602 } else { 603 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index])); 604 nextp = pt_ops.get_pud_virt(next_phys); 605 } 606 607 create_pud_mapping(nextp, va, pa, sz, prot); 608 } 609 610 #define pgd_next_t p4d_t 611 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \ 612 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \ 613 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va))) 614 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \ 615 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \ 616 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa))) 617 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 618 (pgtable_l5_enabled ? \ 619 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \ 620 (pgtable_l4_enabled ? \ 621 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \ 622 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot))) 623 #define fixmap_pgd_next (pgtable_l5_enabled ? \ 624 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \ 625 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd)) 626 #define trampoline_pgd_next (pgtable_l5_enabled ? \ 627 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \ 628 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd)) 629 #else 630 #define pgd_next_t pte_t 631 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va) 632 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa) 633 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 634 create_pte_mapping(__nextp, __va, __pa, __sz, __prot) 635 #define fixmap_pgd_next ((uintptr_t)fixmap_pte) 636 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 637 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 638 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 639 #endif /* __PAGETABLE_PMD_FOLDED */ 640 641 void __init create_pgd_mapping(pgd_t *pgdp, 642 uintptr_t va, phys_addr_t pa, 643 phys_addr_t sz, pgprot_t prot) 644 { 645 pgd_next_t *nextp; 646 phys_addr_t next_phys; 647 uintptr_t pgd_idx = pgd_index(va); 648 649 if (sz == PGDIR_SIZE) { 650 if (pgd_val(pgdp[pgd_idx]) == 0) 651 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot); 652 return; 653 } 654 655 if (pgd_val(pgdp[pgd_idx]) == 0) { 656 next_phys = alloc_pgd_next(va); 657 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE); 658 nextp = get_pgd_next_virt(next_phys); 659 memset(nextp, 0, PAGE_SIZE); 660 } else { 661 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx])); 662 nextp = get_pgd_next_virt(next_phys); 663 } 664 665 create_pgd_next_mapping(nextp, va, pa, sz, prot); 666 } 667 668 static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va, 669 phys_addr_t size) 670 { 671 if (pgtable_l5_enabled && 672 !(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE) 673 return P4D_SIZE; 674 675 if (pgtable_l4_enabled && 676 !(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE) 677 return PUD_SIZE; 678 679 if (IS_ENABLED(CONFIG_64BIT) && 680 !(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE) 681 return PMD_SIZE; 682 683 return PAGE_SIZE; 684 } 685 686 #ifdef CONFIG_XIP_KERNEL 687 #define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base)) 688 extern char _xiprom[], _exiprom[], __data_loc; 689 690 /* called from head.S with MMU off */ 691 asmlinkage void __init __copy_data(void) 692 { 693 void *from = (void *)(&__data_loc); 694 void *to = (void *)CONFIG_PHYS_RAM_BASE; 695 size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata)); 696 697 memcpy(to, from, sz); 698 } 699 #endif 700 701 #ifdef CONFIG_STRICT_KERNEL_RWX 702 static __init pgprot_t pgprot_from_va(uintptr_t va) 703 { 704 if (is_va_kernel_text(va)) 705 return PAGE_KERNEL_READ_EXEC; 706 707 /* 708 * In 64-bit kernel, the kernel mapping is outside the linear mapping so 709 * we must protect its linear mapping alias from being executed and 710 * written. 711 * And rodata section is marked readonly in mark_rodata_ro. 712 */ 713 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va)) 714 return PAGE_KERNEL_READ; 715 716 return PAGE_KERNEL; 717 } 718 719 void mark_rodata_ro(void) 720 { 721 set_kernel_memory(__start_rodata, _data, set_memory_ro); 722 if (IS_ENABLED(CONFIG_64BIT)) 723 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data), 724 set_memory_ro); 725 } 726 #else 727 static __init pgprot_t pgprot_from_va(uintptr_t va) 728 { 729 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va)) 730 return PAGE_KERNEL; 731 732 return PAGE_KERNEL_EXEC; 733 } 734 #endif /* CONFIG_STRICT_KERNEL_RWX */ 735 736 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 737 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa); 738 739 static void __init disable_pgtable_l5(void) 740 { 741 pgtable_l5_enabled = false; 742 kernel_map.page_offset = PAGE_OFFSET_L4; 743 satp_mode = SATP_MODE_48; 744 } 745 746 static void __init disable_pgtable_l4(void) 747 { 748 pgtable_l4_enabled = false; 749 kernel_map.page_offset = PAGE_OFFSET_L3; 750 satp_mode = SATP_MODE_39; 751 } 752 753 static int __init print_no4lvl(char *p) 754 { 755 pr_info("Disabled 4-level and 5-level paging"); 756 return 0; 757 } 758 early_param("no4lvl", print_no4lvl); 759 760 static int __init print_no5lvl(char *p) 761 { 762 pr_info("Disabled 5-level paging"); 763 return 0; 764 } 765 early_param("no5lvl", print_no5lvl); 766 767 /* 768 * There is a simple way to determine if 4-level is supported by the 769 * underlying hardware: establish 1:1 mapping in 4-level page table mode 770 * then read SATP to see if the configuration was taken into account 771 * meaning sv48 is supported. 772 */ 773 static __init void set_satp_mode(uintptr_t dtb_pa) 774 { 775 u64 identity_satp, hw_satp; 776 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; 777 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa); 778 779 if (satp_mode_cmdline == SATP_MODE_57) { 780 disable_pgtable_l5(); 781 } else if (satp_mode_cmdline == SATP_MODE_48) { 782 disable_pgtable_l5(); 783 disable_pgtable_l4(); 784 return; 785 } 786 787 create_p4d_mapping(early_p4d, 788 set_satp_mode_pmd, (uintptr_t)early_pud, 789 P4D_SIZE, PAGE_TABLE); 790 create_pud_mapping(early_pud, 791 set_satp_mode_pmd, (uintptr_t)early_pmd, 792 PUD_SIZE, PAGE_TABLE); 793 /* Handle the case where set_satp_mode straddles 2 PMDs */ 794 create_pmd_mapping(early_pmd, 795 set_satp_mode_pmd, set_satp_mode_pmd, 796 PMD_SIZE, PAGE_KERNEL_EXEC); 797 create_pmd_mapping(early_pmd, 798 set_satp_mode_pmd + PMD_SIZE, 799 set_satp_mode_pmd + PMD_SIZE, 800 PMD_SIZE, PAGE_KERNEL_EXEC); 801 retry: 802 create_pgd_mapping(early_pg_dir, 803 set_satp_mode_pmd, 804 pgtable_l5_enabled ? 805 (uintptr_t)early_p4d : (uintptr_t)early_pud, 806 PGDIR_SIZE, PAGE_TABLE); 807 808 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; 809 810 local_flush_tlb_all(); 811 csr_write(CSR_SATP, identity_satp); 812 hw_satp = csr_swap(CSR_SATP, 0ULL); 813 local_flush_tlb_all(); 814 815 if (hw_satp != identity_satp) { 816 if (pgtable_l5_enabled) { 817 disable_pgtable_l5(); 818 memset(early_pg_dir, 0, PAGE_SIZE); 819 goto retry; 820 } 821 disable_pgtable_l4(); 822 } 823 824 memset(early_pg_dir, 0, PAGE_SIZE); 825 memset(early_p4d, 0, PAGE_SIZE); 826 memset(early_pud, 0, PAGE_SIZE); 827 memset(early_pmd, 0, PAGE_SIZE); 828 } 829 #endif 830 831 /* 832 * setup_vm() is called from head.S with MMU-off. 833 * 834 * Following requirements should be honoured for setup_vm() to work 835 * correctly: 836 * 1) It should use PC-relative addressing for accessing kernel symbols. 837 * To achieve this we always use GCC cmodel=medany. 838 * 2) The compiler instrumentation for FTRACE will not work for setup_vm() 839 * so disable compiler instrumentation when FTRACE is enabled. 840 * 841 * Currently, the above requirements are honoured by using custom CFLAGS 842 * for init.o in mm/Makefile. 843 */ 844 845 #ifndef __riscv_cmodel_medany 846 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing." 847 #endif 848 849 #ifdef CONFIG_RELOCATABLE 850 extern unsigned long __rela_dyn_start, __rela_dyn_end; 851 852 static void __init relocate_kernel(void) 853 { 854 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start; 855 /* 856 * This holds the offset between the linked virtual address and the 857 * relocated virtual address. 858 */ 859 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR; 860 /* 861 * This holds the offset between kernel linked virtual address and 862 * physical address. 863 */ 864 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr; 865 866 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) { 867 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset); 868 Elf64_Addr relocated_addr = rela->r_addend; 869 870 if (rela->r_info != R_RISCV_RELATIVE) 871 continue; 872 873 /* 874 * Make sure to not relocate vdso symbols like rt_sigreturn 875 * which are linked from the address 0 in vmlinux since 876 * vdso symbol addresses are actually used as an offset from 877 * mm->context.vdso in VDSO_OFFSET macro. 878 */ 879 if (relocated_addr >= KERNEL_LINK_ADDR) 880 relocated_addr += reloc_offset; 881 882 *(Elf64_Addr *)addr = relocated_addr; 883 } 884 } 885 #endif /* CONFIG_RELOCATABLE */ 886 887 #ifdef CONFIG_XIP_KERNEL 888 static void __init create_kernel_page_table(pgd_t *pgdir, 889 __always_unused bool early) 890 { 891 uintptr_t va, end_va; 892 893 /* Map the flash resident part */ 894 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz; 895 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 896 create_pgd_mapping(pgdir, va, 897 kernel_map.xiprom + (va - kernel_map.virt_addr), 898 PMD_SIZE, PAGE_KERNEL_EXEC); 899 900 /* Map the data in RAM */ 901 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size; 902 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) 903 create_pgd_mapping(pgdir, va, 904 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), 905 PMD_SIZE, PAGE_KERNEL); 906 } 907 #else 908 static void __init create_kernel_page_table(pgd_t *pgdir, bool early) 909 { 910 uintptr_t va, end_va; 911 912 end_va = kernel_map.virt_addr + kernel_map.size; 913 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 914 create_pgd_mapping(pgdir, va, 915 kernel_map.phys_addr + (va - kernel_map.virt_addr), 916 PMD_SIZE, 917 early ? 918 PAGE_KERNEL_EXEC : pgprot_from_va(va)); 919 } 920 #endif 921 922 /* 923 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel, 924 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR 925 * entry. 926 */ 927 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va, 928 uintptr_t dtb_pa) 929 { 930 #ifndef CONFIG_BUILTIN_DTB 931 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); 932 933 /* Make sure the fdt fixmap address is always aligned on PMD size */ 934 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE)); 935 936 /* In 32-bit only, the fdt lies in its own PGD */ 937 if (!IS_ENABLED(CONFIG_64BIT)) { 938 create_pgd_mapping(early_pg_dir, fix_fdt_va, 939 pa, MAX_FDT_SIZE, PAGE_KERNEL); 940 } else { 941 create_pmd_mapping(fixmap_pmd, fix_fdt_va, 942 pa, PMD_SIZE, PAGE_KERNEL); 943 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE, 944 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); 945 } 946 947 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1)); 948 #else 949 /* 950 * For 64-bit kernel, __va can't be used since it would return a linear 951 * mapping address whereas dtb_early_va will be used before 952 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the 953 * kernel is mapped in the linear mapping, that makes no difference. 954 */ 955 dtb_early_va = kernel_mapping_pa_to_va(dtb_pa); 956 #endif 957 958 dtb_early_pa = dtb_pa; 959 } 960 961 /* 962 * MMU is not enabled, the page tables are allocated directly using 963 * early_pmd/pud/p4d and the address returned is the physical one. 964 */ 965 static void __init pt_ops_set_early(void) 966 { 967 pt_ops.alloc_pte = alloc_pte_early; 968 pt_ops.get_pte_virt = get_pte_virt_early; 969 #ifndef __PAGETABLE_PMD_FOLDED 970 pt_ops.alloc_pmd = alloc_pmd_early; 971 pt_ops.get_pmd_virt = get_pmd_virt_early; 972 pt_ops.alloc_pud = alloc_pud_early; 973 pt_ops.get_pud_virt = get_pud_virt_early; 974 pt_ops.alloc_p4d = alloc_p4d_early; 975 pt_ops.get_p4d_virt = get_p4d_virt_early; 976 #endif 977 } 978 979 /* 980 * MMU is enabled but page table setup is not complete yet. 981 * fixmap page table alloc functions must be used as a means to temporarily 982 * map the allocated physical pages since the linear mapping does not exist yet. 983 * 984 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va, 985 * but it will be used as described above. 986 */ 987 static void __init pt_ops_set_fixmap(void) 988 { 989 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap); 990 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap); 991 #ifndef __PAGETABLE_PMD_FOLDED 992 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap); 993 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap); 994 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap); 995 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap); 996 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap); 997 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap); 998 #endif 999 } 1000 1001 /* 1002 * MMU is enabled and page table setup is complete, so from now, we can use 1003 * generic page allocation functions to setup page table. 1004 */ 1005 static void __init pt_ops_set_late(void) 1006 { 1007 pt_ops.alloc_pte = alloc_pte_late; 1008 pt_ops.get_pte_virt = get_pte_virt_late; 1009 #ifndef __PAGETABLE_PMD_FOLDED 1010 pt_ops.alloc_pmd = alloc_pmd_late; 1011 pt_ops.get_pmd_virt = get_pmd_virt_late; 1012 pt_ops.alloc_pud = alloc_pud_late; 1013 pt_ops.get_pud_virt = get_pud_virt_late; 1014 pt_ops.alloc_p4d = alloc_p4d_late; 1015 pt_ops.get_p4d_virt = get_p4d_virt_late; 1016 #endif 1017 } 1018 1019 #ifdef CONFIG_RANDOMIZE_BASE 1020 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa); 1021 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa); 1022 1023 static int __init print_nokaslr(char *p) 1024 { 1025 pr_info("Disabled KASLR"); 1026 return 0; 1027 } 1028 early_param("nokaslr", print_nokaslr); 1029 1030 unsigned long kaslr_offset(void) 1031 { 1032 return kernel_map.virt_offset; 1033 } 1034 #endif 1035 1036 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1037 { 1038 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1039 1040 #ifdef CONFIG_RANDOMIZE_BASE 1041 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) { 1042 u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa); 1043 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start); 1044 u32 nr_pos; 1045 1046 /* 1047 * Compute the number of positions available: we are limited 1048 * by the early page table that only has one PUD and we must 1049 * be aligned on PMD_SIZE. 1050 */ 1051 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE; 1052 1053 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE; 1054 } 1055 #endif 1056 1057 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset; 1058 1059 #ifdef CONFIG_XIP_KERNEL 1060 #ifdef CONFIG_64BIT 1061 kernel_map.page_offset = PAGE_OFFSET_L3; 1062 #else 1063 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1064 #endif 1065 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; 1066 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); 1067 1068 phys_ram_base = CONFIG_PHYS_RAM_BASE; 1069 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; 1070 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); 1071 1072 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; 1073 #else 1074 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1075 kernel_map.phys_addr = (uintptr_t)(&_start); 1076 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1077 #endif 1078 1079 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 1080 set_satp_mode(dtb_pa); 1081 #endif 1082 1083 /* 1084 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1085 * where we have the system memory layout: this allows us to align 1086 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1087 * for the linear mapping. This is only possible because the kernel 1088 * mapping lies outside the linear mapping. 1089 * In 32-bit however, as the kernel resides in the linear mapping, 1090 * setup_vm_final can not change the mapping established here, 1091 * otherwise the same kernel addresses would get mapped to different 1092 * physical addresses (if the start of dram is different from the 1093 * kernel physical address start). 1094 */ 1095 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1096 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1097 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1098 1099 /* 1100 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit 1101 * kernel, whereas for 64-bit kernel, the end of the virtual address 1102 * space is occupied by the modules/BPF/kernel mappings which reduces 1103 * the available size of the linear mapping. 1104 */ 1105 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); 1106 1107 /* Sanity check alignment and size */ 1108 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1109 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1110 1111 #ifdef CONFIG_64BIT 1112 /* 1113 * The last 4K bytes of the addressable memory can not be mapped because 1114 * of IS_ERR_VALUE macro. 1115 */ 1116 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1117 #endif 1118 1119 #ifdef CONFIG_RELOCATABLE 1120 /* 1121 * Early page table uses only one PUD, which makes it possible 1122 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1123 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1124 * since a part of the kernel would not get mapped. 1125 */ 1126 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1127 relocate_kernel(); 1128 #endif 1129 1130 apply_early_boot_alternatives(); 1131 pt_ops_set_early(); 1132 1133 /* Setup early PGD for fixmap */ 1134 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1135 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1136 1137 #ifndef __PAGETABLE_PMD_FOLDED 1138 /* Setup fixmap P4D and PUD */ 1139 if (pgtable_l5_enabled) 1140 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1141 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1142 /* Setup fixmap PUD and PMD */ 1143 if (pgtable_l4_enabled) 1144 create_pud_mapping(fixmap_pud, FIXADDR_START, 1145 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1146 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1147 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1148 /* Setup trampoline PGD and PMD */ 1149 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1150 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1151 if (pgtable_l5_enabled) 1152 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1153 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1154 if (pgtable_l4_enabled) 1155 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1156 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1157 #ifdef CONFIG_XIP_KERNEL 1158 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1159 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); 1160 #else 1161 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1162 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1163 #endif 1164 #else 1165 /* Setup trampoline PGD */ 1166 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1167 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1168 #endif 1169 1170 /* 1171 * Setup early PGD covering entire kernel which will allow 1172 * us to reach paging_init(). We map all memory banks later 1173 * in setup_vm_final() below. 1174 */ 1175 create_kernel_page_table(early_pg_dir, true); 1176 1177 /* Setup early mapping for FDT early scan */ 1178 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1179 1180 /* 1181 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1182 * range can not span multiple pmds. 1183 */ 1184 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1185 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1186 1187 #ifndef __PAGETABLE_PMD_FOLDED 1188 /* 1189 * Early ioremap fixmap is already created as it lies within first 2MB 1190 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1191 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1192 * the user if not. 1193 */ 1194 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1195 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1196 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1197 WARN_ON(1); 1198 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1199 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1200 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1201 fix_to_virt(FIX_BTMAP_BEGIN)); 1202 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1203 fix_to_virt(FIX_BTMAP_END)); 1204 1205 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1206 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1207 } 1208 #endif 1209 1210 pt_ops_set_fixmap(); 1211 } 1212 1213 static void __init create_linear_mapping_range(phys_addr_t start, 1214 phys_addr_t end, 1215 uintptr_t fixed_map_size) 1216 { 1217 phys_addr_t pa; 1218 uintptr_t va, map_size; 1219 1220 for (pa = start; pa < end; pa += map_size) { 1221 va = (uintptr_t)__va(pa); 1222 map_size = fixed_map_size ? fixed_map_size : 1223 best_map_size(pa, va, end - pa); 1224 1225 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1226 pgprot_from_va(va)); 1227 } 1228 } 1229 1230 static void __init create_linear_mapping_page_table(void) 1231 { 1232 phys_addr_t start, end; 1233 phys_addr_t kfence_pool __maybe_unused; 1234 u64 i; 1235 1236 #ifdef CONFIG_STRICT_KERNEL_RWX 1237 phys_addr_t ktext_start = __pa_symbol(_start); 1238 phys_addr_t ktext_size = __init_data_begin - _start; 1239 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1240 phys_addr_t krodata_size = _data - __start_rodata; 1241 1242 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1243 memblock_mark_nomap(ktext_start, ktext_size); 1244 memblock_mark_nomap(krodata_start, krodata_size); 1245 #endif 1246 1247 #ifdef CONFIG_KFENCE 1248 /* 1249 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1250 * before we setup the linear mapping so that we avoid using hugepages 1251 * for this region. 1252 */ 1253 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1254 BUG_ON(!kfence_pool); 1255 1256 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1257 __kfence_pool = __va(kfence_pool); 1258 #endif 1259 1260 /* Map all memory banks in the linear mapping */ 1261 for_each_mem_range(i, &start, &end) { 1262 if (start >= end) 1263 break; 1264 if (start <= __pa(PAGE_OFFSET) && 1265 __pa(PAGE_OFFSET) < end) 1266 start = __pa(PAGE_OFFSET); 1267 if (end >= __pa(PAGE_OFFSET) + memory_limit) 1268 end = __pa(PAGE_OFFSET) + memory_limit; 1269 1270 create_linear_mapping_range(start, end, 0); 1271 } 1272 1273 #ifdef CONFIG_STRICT_KERNEL_RWX 1274 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0); 1275 create_linear_mapping_range(krodata_start, 1276 krodata_start + krodata_size, 0); 1277 1278 memblock_clear_nomap(ktext_start, ktext_size); 1279 memblock_clear_nomap(krodata_start, krodata_size); 1280 #endif 1281 1282 #ifdef CONFIG_KFENCE 1283 create_linear_mapping_range(kfence_pool, 1284 kfence_pool + KFENCE_POOL_SIZE, 1285 PAGE_SIZE); 1286 1287 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1288 #endif 1289 } 1290 1291 static void __init setup_vm_final(void) 1292 { 1293 /* Setup swapper PGD for fixmap */ 1294 #if !defined(CONFIG_64BIT) 1295 /* 1296 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1297 * directly in swapper_pg_dir in addition to the pgd entry that points 1298 * to fixmap_pte. 1299 */ 1300 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1301 1302 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1303 #endif 1304 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1305 __pa_symbol(fixmap_pgd_next), 1306 PGDIR_SIZE, PAGE_TABLE); 1307 1308 /* Map the linear mapping */ 1309 create_linear_mapping_page_table(); 1310 1311 /* Map the kernel */ 1312 if (IS_ENABLED(CONFIG_64BIT)) 1313 create_kernel_page_table(swapper_pg_dir, false); 1314 1315 #ifdef CONFIG_KASAN 1316 kasan_swapper_init(); 1317 #endif 1318 1319 /* Clear fixmap PTE and PMD mappings */ 1320 clear_fixmap(FIX_PTE); 1321 clear_fixmap(FIX_PMD); 1322 clear_fixmap(FIX_PUD); 1323 clear_fixmap(FIX_P4D); 1324 1325 /* Move to swapper page table */ 1326 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1327 local_flush_tlb_all(); 1328 1329 pt_ops_set_late(); 1330 } 1331 #else 1332 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1333 { 1334 dtb_early_va = (void *)dtb_pa; 1335 dtb_early_pa = dtb_pa; 1336 } 1337 1338 static inline void setup_vm_final(void) 1339 { 1340 } 1341 #endif /* CONFIG_MMU */ 1342 1343 /* 1344 * reserve_crashkernel() - reserves memory for crash kernel 1345 * 1346 * This function reserves memory area given in "crashkernel=" kernel command 1347 * line parameter. The memory reserved is used by dump capture kernel when 1348 * primary kernel is crashing. 1349 */ 1350 static void __init arch_reserve_crashkernel(void) 1351 { 1352 unsigned long long low_size = 0; 1353 unsigned long long crash_base, crash_size; 1354 char *cmdline = boot_command_line; 1355 bool high = false; 1356 int ret; 1357 1358 if (!IS_ENABLED(CONFIG_CRASH_RESERVE)) 1359 return; 1360 1361 ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), 1362 &crash_size, &crash_base, 1363 &low_size, &high); 1364 if (ret) 1365 return; 1366 1367 reserve_crashkernel_generic(cmdline, crash_size, crash_base, 1368 low_size, high); 1369 } 1370 1371 void __init paging_init(void) 1372 { 1373 setup_bootmem(); 1374 setup_vm_final(); 1375 1376 /* Depend on that Linear Mapping is ready */ 1377 memblock_allow_resize(); 1378 } 1379 1380 void __init misc_mem_init(void) 1381 { 1382 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1383 arch_numa_init(); 1384 sparse_init(); 1385 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1386 /* The entire VMEMMAP region has been populated. Flush TLB for this region */ 1387 local_flush_tlb_kernel_range(VMEMMAP_START, VMEMMAP_END); 1388 #endif 1389 zone_sizes_init(); 1390 arch_reserve_crashkernel(); 1391 memblock_dump_all(); 1392 } 1393 1394 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1395 void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node, 1396 unsigned long addr, unsigned long next) 1397 { 1398 pmd_set_huge(pmd, virt_to_phys(p), PAGE_KERNEL); 1399 } 1400 1401 int __meminit vmemmap_check_pmd(pmd_t *pmdp, int node, 1402 unsigned long addr, unsigned long next) 1403 { 1404 vmemmap_verify((pte_t *)pmdp, node, addr, next); 1405 return 1; 1406 } 1407 1408 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1409 struct vmem_altmap *altmap) 1410 { 1411 /* 1412 * Note that SPARSEMEM_VMEMMAP is only selected for rv64 and that we 1413 * can't use hugepage mappings for 2-level page table because in case of 1414 * memory hotplug, we are not able to update all the page tables with 1415 * the new PMDs. 1416 */ 1417 return vmemmap_populate_hugepages(start, end, node, NULL); 1418 } 1419 #endif 1420 1421 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1422 /* 1423 * Pre-allocates page-table pages for a specific area in the kernel 1424 * page-table. Only the level which needs to be synchronized between 1425 * all page-tables is allocated because the synchronization can be 1426 * expensive. 1427 */ 1428 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1429 const char *area) 1430 { 1431 unsigned long addr; 1432 const char *lvl; 1433 1434 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1435 pgd_t *pgd = pgd_offset_k(addr); 1436 p4d_t *p4d; 1437 pud_t *pud; 1438 pmd_t *pmd; 1439 1440 lvl = "p4d"; 1441 p4d = p4d_alloc(&init_mm, pgd, addr); 1442 if (!p4d) 1443 goto failed; 1444 1445 if (pgtable_l5_enabled) 1446 continue; 1447 1448 lvl = "pud"; 1449 pud = pud_alloc(&init_mm, p4d, addr); 1450 if (!pud) 1451 goto failed; 1452 1453 if (pgtable_l4_enabled) 1454 continue; 1455 1456 lvl = "pmd"; 1457 pmd = pmd_alloc(&init_mm, pud, addr); 1458 if (!pmd) 1459 goto failed; 1460 } 1461 return; 1462 1463 failed: 1464 /* 1465 * The pages have to be there now or they will be missing in 1466 * process page-tables later. 1467 */ 1468 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1469 } 1470 1471 void __init pgtable_cache_init(void) 1472 { 1473 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1474 if (IS_ENABLED(CONFIG_MODULES)) 1475 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1476 } 1477 #endif 1478