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; 175 176 static int __init early_mem(char *p) 177 { 178 u64 size; 179 180 if (!p) 181 return 1; 182 183 size = memparse(p, &p) & PAGE_MASK; 184 memory_limit = min_t(u64, size, memory_limit); 185 186 pr_notice("Memory limited to %lldMB\n", (u64)memory_limit >> 20); 187 188 return 0; 189 } 190 early_param("mem", early_mem); 191 192 static void __init setup_bootmem(void) 193 { 194 phys_addr_t vmlinux_end = __pa_symbol(&_end); 195 phys_addr_t max_mapped_addr; 196 phys_addr_t phys_ram_end, vmlinux_start; 197 198 if (IS_ENABLED(CONFIG_XIP_KERNEL)) 199 vmlinux_start = __pa_symbol(&_sdata); 200 else 201 vmlinux_start = __pa_symbol(&_start); 202 203 memblock_enforce_memory_limit(memory_limit); 204 205 /* 206 * Make sure we align the reservation on PMD_SIZE since we will 207 * map the kernel in the linear mapping as read-only: we do not want 208 * any allocation to happen between _end and the next pmd aligned page. 209 */ 210 if (IS_ENABLED(CONFIG_64BIT) && IS_ENABLED(CONFIG_STRICT_KERNEL_RWX)) 211 vmlinux_end = (vmlinux_end + PMD_SIZE - 1) & PMD_MASK; 212 /* 213 * Reserve from the start of the kernel to the end of the kernel 214 */ 215 memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); 216 217 phys_ram_end = memblock_end_of_DRAM(); 218 219 /* 220 * Make sure we align the start of the memory on a PMD boundary so that 221 * at worst, we map the linear mapping with PMD mappings. 222 */ 223 if (!IS_ENABLED(CONFIG_XIP_KERNEL)) 224 phys_ram_base = memblock_start_of_DRAM() & PMD_MASK; 225 226 /* 227 * In 64-bit, any use of __va/__pa before this point is wrong as we 228 * did not know the start of DRAM before. 229 */ 230 if (IS_ENABLED(CONFIG_64BIT)) 231 kernel_map.va_pa_offset = PAGE_OFFSET - phys_ram_base; 232 233 /* 234 * memblock allocator is not aware of the fact that last 4K bytes of 235 * the addressable memory can not be mapped because of IS_ERR_VALUE 236 * macro. Make sure that last 4k bytes are not usable by memblock 237 * if end of dram is equal to maximum addressable memory. For 64-bit 238 * kernel, this problem can't happen here as the end of the virtual 239 * address space is occupied by the kernel mapping then this check must 240 * be done as soon as the kernel mapping base address is determined. 241 */ 242 if (!IS_ENABLED(CONFIG_64BIT)) { 243 max_mapped_addr = __pa(~(ulong)0); 244 if (max_mapped_addr == (phys_ram_end - 1)) 245 memblock_set_current_limit(max_mapped_addr - 4096); 246 } 247 248 min_low_pfn = PFN_UP(phys_ram_base); 249 max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); 250 high_memory = (void *)(__va(PFN_PHYS(max_low_pfn))); 251 252 dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn)); 253 set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET); 254 255 reserve_initrd_mem(); 256 257 /* 258 * No allocation should be done before reserving the memory as defined 259 * in the device tree, otherwise the allocation could end up in a 260 * reserved region. 261 */ 262 early_init_fdt_scan_reserved_mem(); 263 264 /* 265 * If DTB is built in, no need to reserve its memblock. 266 * Otherwise, do reserve it but avoid using 267 * early_init_fdt_reserve_self() since __pa() does 268 * not work for DTB pointers that are fixmap addresses 269 */ 270 if (!IS_ENABLED(CONFIG_BUILTIN_DTB)) 271 memblock_reserve(dtb_early_pa, fdt_totalsize(dtb_early_va)); 272 273 dma_contiguous_reserve(dma32_phys_limit); 274 if (IS_ENABLED(CONFIG_64BIT)) 275 hugetlb_cma_reserve(PUD_SHIFT - PAGE_SHIFT); 276 } 277 278 #ifdef CONFIG_MMU 279 struct pt_alloc_ops pt_ops __initdata; 280 281 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 282 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss; 283 static pte_t fixmap_pte[PTRS_PER_PTE] __page_aligned_bss; 284 285 pgd_t early_pg_dir[PTRS_PER_PGD] __initdata __aligned(PAGE_SIZE); 286 287 #ifdef CONFIG_XIP_KERNEL 288 #define pt_ops (*(struct pt_alloc_ops *)XIP_FIXUP(&pt_ops)) 289 #define trampoline_pg_dir ((pgd_t *)XIP_FIXUP(trampoline_pg_dir)) 290 #define fixmap_pte ((pte_t *)XIP_FIXUP(fixmap_pte)) 291 #define early_pg_dir ((pgd_t *)XIP_FIXUP(early_pg_dir)) 292 #endif /* CONFIG_XIP_KERNEL */ 293 294 static const pgprot_t protection_map[16] = { 295 [VM_NONE] = PAGE_NONE, 296 [VM_READ] = PAGE_READ, 297 [VM_WRITE] = PAGE_COPY, 298 [VM_WRITE | VM_READ] = PAGE_COPY, 299 [VM_EXEC] = PAGE_EXEC, 300 [VM_EXEC | VM_READ] = PAGE_READ_EXEC, 301 [VM_EXEC | VM_WRITE] = PAGE_COPY_EXEC, 302 [VM_EXEC | VM_WRITE | VM_READ] = PAGE_COPY_EXEC, 303 [VM_SHARED] = PAGE_NONE, 304 [VM_SHARED | VM_READ] = PAGE_READ, 305 [VM_SHARED | VM_WRITE] = PAGE_SHARED, 306 [VM_SHARED | VM_WRITE | VM_READ] = PAGE_SHARED, 307 [VM_SHARED | VM_EXEC] = PAGE_EXEC, 308 [VM_SHARED | VM_EXEC | VM_READ] = PAGE_READ_EXEC, 309 [VM_SHARED | VM_EXEC | VM_WRITE] = PAGE_SHARED_EXEC, 310 [VM_SHARED | VM_EXEC | VM_WRITE | VM_READ] = PAGE_SHARED_EXEC 311 }; 312 DECLARE_VM_GET_PAGE_PROT 313 314 void __set_fixmap(enum fixed_addresses idx, phys_addr_t phys, pgprot_t prot) 315 { 316 unsigned long addr = __fix_to_virt(idx); 317 pte_t *ptep; 318 319 BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses); 320 321 ptep = &fixmap_pte[pte_index(addr)]; 322 323 if (pgprot_val(prot)) 324 set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot)); 325 else 326 pte_clear(&init_mm, addr, ptep); 327 local_flush_tlb_page(addr); 328 } 329 330 static inline pte_t *__init get_pte_virt_early(phys_addr_t pa) 331 { 332 return (pte_t *)((uintptr_t)pa); 333 } 334 335 static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa) 336 { 337 clear_fixmap(FIX_PTE); 338 return (pte_t *)set_fixmap_offset(FIX_PTE, pa); 339 } 340 341 static inline pte_t *__init get_pte_virt_late(phys_addr_t pa) 342 { 343 return (pte_t *) __va(pa); 344 } 345 346 static inline phys_addr_t __init alloc_pte_early(uintptr_t va) 347 { 348 /* 349 * We only create PMD or PGD early mappings so we 350 * should never reach here with MMU disabled. 351 */ 352 BUG(); 353 } 354 355 static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va) 356 { 357 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 358 } 359 360 static phys_addr_t __init alloc_pte_late(uintptr_t va) 361 { 362 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 363 364 BUG_ON(!ptdesc || !pagetable_pte_ctor(ptdesc)); 365 return __pa((pte_t *)ptdesc_address(ptdesc)); 366 } 367 368 static void __init create_pte_mapping(pte_t *ptep, 369 uintptr_t va, phys_addr_t pa, 370 phys_addr_t sz, pgprot_t prot) 371 { 372 uintptr_t pte_idx = pte_index(va); 373 374 BUG_ON(sz != PAGE_SIZE); 375 376 if (pte_none(ptep[pte_idx])) 377 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot); 378 } 379 380 #ifndef __PAGETABLE_PMD_FOLDED 381 382 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss; 383 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; 384 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); 385 386 #ifdef CONFIG_XIP_KERNEL 387 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd)) 388 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd)) 389 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd)) 390 #endif /* CONFIG_XIP_KERNEL */ 391 392 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss; 393 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss; 394 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); 395 396 #ifdef CONFIG_XIP_KERNEL 397 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d)) 398 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d)) 399 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d)) 400 #endif /* CONFIG_XIP_KERNEL */ 401 402 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; 403 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; 404 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); 405 406 #ifdef CONFIG_XIP_KERNEL 407 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud)) 408 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud)) 409 #define early_pud ((pud_t *)XIP_FIXUP(early_pud)) 410 #endif /* CONFIG_XIP_KERNEL */ 411 412 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) 413 { 414 /* Before MMU is enabled */ 415 return (pmd_t *)((uintptr_t)pa); 416 } 417 418 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa) 419 { 420 clear_fixmap(FIX_PMD); 421 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa); 422 } 423 424 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa) 425 { 426 return (pmd_t *) __va(pa); 427 } 428 429 static phys_addr_t __init alloc_pmd_early(uintptr_t va) 430 { 431 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); 432 433 return (uintptr_t)early_pmd; 434 } 435 436 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va) 437 { 438 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 439 } 440 441 static phys_addr_t __init alloc_pmd_late(uintptr_t va) 442 { 443 struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0); 444 445 BUG_ON(!ptdesc || !pagetable_pmd_ctor(ptdesc)); 446 return __pa((pmd_t *)ptdesc_address(ptdesc)); 447 } 448 449 static void __init create_pmd_mapping(pmd_t *pmdp, 450 uintptr_t va, phys_addr_t pa, 451 phys_addr_t sz, pgprot_t prot) 452 { 453 pte_t *ptep; 454 phys_addr_t pte_phys; 455 uintptr_t pmd_idx = pmd_index(va); 456 457 if (sz == PMD_SIZE) { 458 if (pmd_none(pmdp[pmd_idx])) 459 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pa), prot); 460 return; 461 } 462 463 if (pmd_none(pmdp[pmd_idx])) { 464 pte_phys = pt_ops.alloc_pte(va); 465 pmdp[pmd_idx] = pfn_pmd(PFN_DOWN(pte_phys), PAGE_TABLE); 466 ptep = pt_ops.get_pte_virt(pte_phys); 467 memset(ptep, 0, PAGE_SIZE); 468 } else { 469 pte_phys = PFN_PHYS(_pmd_pfn(pmdp[pmd_idx])); 470 ptep = pt_ops.get_pte_virt(pte_phys); 471 } 472 473 create_pte_mapping(ptep, va, pa, sz, prot); 474 } 475 476 static pud_t *__init get_pud_virt_early(phys_addr_t pa) 477 { 478 return (pud_t *)((uintptr_t)pa); 479 } 480 481 static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa) 482 { 483 clear_fixmap(FIX_PUD); 484 return (pud_t *)set_fixmap_offset(FIX_PUD, pa); 485 } 486 487 static pud_t *__init get_pud_virt_late(phys_addr_t pa) 488 { 489 return (pud_t *)__va(pa); 490 } 491 492 static phys_addr_t __init alloc_pud_early(uintptr_t va) 493 { 494 /* Only one PUD is available for early mapping */ 495 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 496 497 return (uintptr_t)early_pud; 498 } 499 500 static phys_addr_t __init alloc_pud_fixmap(uintptr_t va) 501 { 502 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 503 } 504 505 static phys_addr_t alloc_pud_late(uintptr_t va) 506 { 507 unsigned long vaddr; 508 509 vaddr = __get_free_page(GFP_KERNEL); 510 BUG_ON(!vaddr); 511 return __pa(vaddr); 512 } 513 514 static p4d_t *__init get_p4d_virt_early(phys_addr_t pa) 515 { 516 return (p4d_t *)((uintptr_t)pa); 517 } 518 519 static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa) 520 { 521 clear_fixmap(FIX_P4D); 522 return (p4d_t *)set_fixmap_offset(FIX_P4D, pa); 523 } 524 525 static p4d_t *__init get_p4d_virt_late(phys_addr_t pa) 526 { 527 return (p4d_t *)__va(pa); 528 } 529 530 static phys_addr_t __init alloc_p4d_early(uintptr_t va) 531 { 532 /* Only one P4D is available for early mapping */ 533 BUG_ON((va - kernel_map.virt_addr) >> PGDIR_SHIFT); 534 535 return (uintptr_t)early_p4d; 536 } 537 538 static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va) 539 { 540 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 541 } 542 543 static phys_addr_t alloc_p4d_late(uintptr_t va) 544 { 545 unsigned long vaddr; 546 547 vaddr = __get_free_page(GFP_KERNEL); 548 BUG_ON(!vaddr); 549 return __pa(vaddr); 550 } 551 552 static void __init create_pud_mapping(pud_t *pudp, 553 uintptr_t va, phys_addr_t pa, 554 phys_addr_t sz, pgprot_t prot) 555 { 556 pmd_t *nextp; 557 phys_addr_t next_phys; 558 uintptr_t pud_index = pud_index(va); 559 560 if (sz == PUD_SIZE) { 561 if (pud_val(pudp[pud_index]) == 0) 562 pudp[pud_index] = pfn_pud(PFN_DOWN(pa), prot); 563 return; 564 } 565 566 if (pud_val(pudp[pud_index]) == 0) { 567 next_phys = pt_ops.alloc_pmd(va); 568 pudp[pud_index] = pfn_pud(PFN_DOWN(next_phys), PAGE_TABLE); 569 nextp = pt_ops.get_pmd_virt(next_phys); 570 memset(nextp, 0, PAGE_SIZE); 571 } else { 572 next_phys = PFN_PHYS(_pud_pfn(pudp[pud_index])); 573 nextp = pt_ops.get_pmd_virt(next_phys); 574 } 575 576 create_pmd_mapping(nextp, va, pa, sz, prot); 577 } 578 579 static void __init create_p4d_mapping(p4d_t *p4dp, 580 uintptr_t va, phys_addr_t pa, 581 phys_addr_t sz, pgprot_t prot) 582 { 583 pud_t *nextp; 584 phys_addr_t next_phys; 585 uintptr_t p4d_index = p4d_index(va); 586 587 if (sz == P4D_SIZE) { 588 if (p4d_val(p4dp[p4d_index]) == 0) 589 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(pa), prot); 590 return; 591 } 592 593 if (p4d_val(p4dp[p4d_index]) == 0) { 594 next_phys = pt_ops.alloc_pud(va); 595 p4dp[p4d_index] = pfn_p4d(PFN_DOWN(next_phys), PAGE_TABLE); 596 nextp = pt_ops.get_pud_virt(next_phys); 597 memset(nextp, 0, PAGE_SIZE); 598 } else { 599 next_phys = PFN_PHYS(_p4d_pfn(p4dp[p4d_index])); 600 nextp = pt_ops.get_pud_virt(next_phys); 601 } 602 603 create_pud_mapping(nextp, va, pa, sz, prot); 604 } 605 606 #define pgd_next_t p4d_t 607 #define alloc_pgd_next(__va) (pgtable_l5_enabled ? \ 608 pt_ops.alloc_p4d(__va) : (pgtable_l4_enabled ? \ 609 pt_ops.alloc_pud(__va) : pt_ops.alloc_pmd(__va))) 610 #define get_pgd_next_virt(__pa) (pgtable_l5_enabled ? \ 611 pt_ops.get_p4d_virt(__pa) : (pgd_next_t *)(pgtable_l4_enabled ? \ 612 pt_ops.get_pud_virt(__pa) : (pud_t *)pt_ops.get_pmd_virt(__pa))) 613 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 614 (pgtable_l5_enabled ? \ 615 create_p4d_mapping(__nextp, __va, __pa, __sz, __prot) : \ 616 (pgtable_l4_enabled ? \ 617 create_pud_mapping((pud_t *)__nextp, __va, __pa, __sz, __prot) : \ 618 create_pmd_mapping((pmd_t *)__nextp, __va, __pa, __sz, __prot))) 619 #define fixmap_pgd_next (pgtable_l5_enabled ? \ 620 (uintptr_t)fixmap_p4d : (pgtable_l4_enabled ? \ 621 (uintptr_t)fixmap_pud : (uintptr_t)fixmap_pmd)) 622 #define trampoline_pgd_next (pgtable_l5_enabled ? \ 623 (uintptr_t)trampoline_p4d : (pgtable_l4_enabled ? \ 624 (uintptr_t)trampoline_pud : (uintptr_t)trampoline_pmd)) 625 #else 626 #define pgd_next_t pte_t 627 #define alloc_pgd_next(__va) pt_ops.alloc_pte(__va) 628 #define get_pgd_next_virt(__pa) pt_ops.get_pte_virt(__pa) 629 #define create_pgd_next_mapping(__nextp, __va, __pa, __sz, __prot) \ 630 create_pte_mapping(__nextp, __va, __pa, __sz, __prot) 631 #define fixmap_pgd_next ((uintptr_t)fixmap_pte) 632 #define create_p4d_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 633 #define create_pud_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 634 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0) 635 #endif /* __PAGETABLE_PMD_FOLDED */ 636 637 void __init create_pgd_mapping(pgd_t *pgdp, 638 uintptr_t va, phys_addr_t pa, 639 phys_addr_t sz, pgprot_t prot) 640 { 641 pgd_next_t *nextp; 642 phys_addr_t next_phys; 643 uintptr_t pgd_idx = pgd_index(va); 644 645 if (sz == PGDIR_SIZE) { 646 if (pgd_val(pgdp[pgd_idx]) == 0) 647 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(pa), prot); 648 return; 649 } 650 651 if (pgd_val(pgdp[pgd_idx]) == 0) { 652 next_phys = alloc_pgd_next(va); 653 pgdp[pgd_idx] = pfn_pgd(PFN_DOWN(next_phys), PAGE_TABLE); 654 nextp = get_pgd_next_virt(next_phys); 655 memset(nextp, 0, PAGE_SIZE); 656 } else { 657 next_phys = PFN_PHYS(_pgd_pfn(pgdp[pgd_idx])); 658 nextp = get_pgd_next_virt(next_phys); 659 } 660 661 create_pgd_next_mapping(nextp, va, pa, sz, prot); 662 } 663 664 static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va, 665 phys_addr_t size) 666 { 667 if (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE) 668 return PGDIR_SIZE; 669 670 if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE) 671 return P4D_SIZE; 672 673 if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE) 674 return PUD_SIZE; 675 676 if (!(pa & (PMD_SIZE - 1)) && !(va & (PMD_SIZE - 1)) && size >= PMD_SIZE) 677 return PMD_SIZE; 678 679 return PAGE_SIZE; 680 } 681 682 #ifdef CONFIG_XIP_KERNEL 683 #define phys_ram_base (*(phys_addr_t *)XIP_FIXUP(&phys_ram_base)) 684 extern char _xiprom[], _exiprom[], __data_loc; 685 686 /* called from head.S with MMU off */ 687 asmlinkage void __init __copy_data(void) 688 { 689 void *from = (void *)(&__data_loc); 690 void *to = (void *)CONFIG_PHYS_RAM_BASE; 691 size_t sz = (size_t)((uintptr_t)(&_end) - (uintptr_t)(&_sdata)); 692 693 memcpy(to, from, sz); 694 } 695 #endif 696 697 #ifdef CONFIG_STRICT_KERNEL_RWX 698 static __init pgprot_t pgprot_from_va(uintptr_t va) 699 { 700 if (is_va_kernel_text(va)) 701 return PAGE_KERNEL_READ_EXEC; 702 703 /* 704 * In 64-bit kernel, the kernel mapping is outside the linear mapping so 705 * we must protect its linear mapping alias from being executed and 706 * written. 707 * And rodata section is marked readonly in mark_rodata_ro. 708 */ 709 if (IS_ENABLED(CONFIG_64BIT) && is_va_kernel_lm_alias_text(va)) 710 return PAGE_KERNEL_READ; 711 712 return PAGE_KERNEL; 713 } 714 715 void mark_rodata_ro(void) 716 { 717 set_kernel_memory(__start_rodata, _data, set_memory_ro); 718 if (IS_ENABLED(CONFIG_64BIT)) 719 set_kernel_memory(lm_alias(__start_rodata), lm_alias(_data), 720 set_memory_ro); 721 722 debug_checkwx(); 723 } 724 #else 725 static __init pgprot_t pgprot_from_va(uintptr_t va) 726 { 727 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va)) 728 return PAGE_KERNEL; 729 730 return PAGE_KERNEL_EXEC; 731 } 732 #endif /* CONFIG_STRICT_KERNEL_RWX */ 733 734 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 735 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa); 736 737 static void __init disable_pgtable_l5(void) 738 { 739 pgtable_l5_enabled = false; 740 kernel_map.page_offset = PAGE_OFFSET_L4; 741 satp_mode = SATP_MODE_48; 742 } 743 744 static void __init disable_pgtable_l4(void) 745 { 746 pgtable_l4_enabled = false; 747 kernel_map.page_offset = PAGE_OFFSET_L3; 748 satp_mode = SATP_MODE_39; 749 } 750 751 static int __init print_no4lvl(char *p) 752 { 753 pr_info("Disabled 4-level and 5-level paging"); 754 return 0; 755 } 756 early_param("no4lvl", print_no4lvl); 757 758 static int __init print_no5lvl(char *p) 759 { 760 pr_info("Disabled 5-level paging"); 761 return 0; 762 } 763 early_param("no5lvl", print_no5lvl); 764 765 /* 766 * There is a simple way to determine if 4-level is supported by the 767 * underlying hardware: establish 1:1 mapping in 4-level page table mode 768 * then read SATP to see if the configuration was taken into account 769 * meaning sv48 is supported. 770 */ 771 static __init void set_satp_mode(uintptr_t dtb_pa) 772 { 773 u64 identity_satp, hw_satp; 774 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; 775 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa); 776 777 if (satp_mode_cmdline == SATP_MODE_57) { 778 disable_pgtable_l5(); 779 } else if (satp_mode_cmdline == SATP_MODE_48) { 780 disable_pgtable_l5(); 781 disable_pgtable_l4(); 782 return; 783 } 784 785 create_p4d_mapping(early_p4d, 786 set_satp_mode_pmd, (uintptr_t)early_pud, 787 P4D_SIZE, PAGE_TABLE); 788 create_pud_mapping(early_pud, 789 set_satp_mode_pmd, (uintptr_t)early_pmd, 790 PUD_SIZE, PAGE_TABLE); 791 /* Handle the case where set_satp_mode straddles 2 PMDs */ 792 create_pmd_mapping(early_pmd, 793 set_satp_mode_pmd, set_satp_mode_pmd, 794 PMD_SIZE, PAGE_KERNEL_EXEC); 795 create_pmd_mapping(early_pmd, 796 set_satp_mode_pmd + PMD_SIZE, 797 set_satp_mode_pmd + PMD_SIZE, 798 PMD_SIZE, PAGE_KERNEL_EXEC); 799 retry: 800 create_pgd_mapping(early_pg_dir, 801 set_satp_mode_pmd, 802 pgtable_l5_enabled ? 803 (uintptr_t)early_p4d : (uintptr_t)early_pud, 804 PGDIR_SIZE, PAGE_TABLE); 805 806 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; 807 808 local_flush_tlb_all(); 809 csr_write(CSR_SATP, identity_satp); 810 hw_satp = csr_swap(CSR_SATP, 0ULL); 811 local_flush_tlb_all(); 812 813 if (hw_satp != identity_satp) { 814 if (pgtable_l5_enabled) { 815 disable_pgtable_l5(); 816 memset(early_pg_dir, 0, PAGE_SIZE); 817 goto retry; 818 } 819 disable_pgtable_l4(); 820 } 821 822 memset(early_pg_dir, 0, PAGE_SIZE); 823 memset(early_p4d, 0, PAGE_SIZE); 824 memset(early_pud, 0, PAGE_SIZE); 825 memset(early_pmd, 0, PAGE_SIZE); 826 } 827 #endif 828 829 /* 830 * setup_vm() is called from head.S with MMU-off. 831 * 832 * Following requirements should be honoured for setup_vm() to work 833 * correctly: 834 * 1) It should use PC-relative addressing for accessing kernel symbols. 835 * To achieve this we always use GCC cmodel=medany. 836 * 2) The compiler instrumentation for FTRACE will not work for setup_vm() 837 * so disable compiler instrumentation when FTRACE is enabled. 838 * 839 * Currently, the above requirements are honoured by using custom CFLAGS 840 * for init.o in mm/Makefile. 841 */ 842 843 #ifndef __riscv_cmodel_medany 844 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing." 845 #endif 846 847 #ifdef CONFIG_RELOCATABLE 848 extern unsigned long __rela_dyn_start, __rela_dyn_end; 849 850 static void __init relocate_kernel(void) 851 { 852 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start; 853 /* 854 * This holds the offset between the linked virtual address and the 855 * relocated virtual address. 856 */ 857 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR; 858 /* 859 * This holds the offset between kernel linked virtual address and 860 * physical address. 861 */ 862 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr; 863 864 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) { 865 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset); 866 Elf64_Addr relocated_addr = rela->r_addend; 867 868 if (rela->r_info != R_RISCV_RELATIVE) 869 continue; 870 871 /* 872 * Make sure to not relocate vdso symbols like rt_sigreturn 873 * which are linked from the address 0 in vmlinux since 874 * vdso symbol addresses are actually used as an offset from 875 * mm->context.vdso in VDSO_OFFSET macro. 876 */ 877 if (relocated_addr >= KERNEL_LINK_ADDR) 878 relocated_addr += reloc_offset; 879 880 *(Elf64_Addr *)addr = relocated_addr; 881 } 882 } 883 #endif /* CONFIG_RELOCATABLE */ 884 885 #ifdef CONFIG_XIP_KERNEL 886 static void __init create_kernel_page_table(pgd_t *pgdir, 887 __always_unused bool early) 888 { 889 uintptr_t va, end_va; 890 891 /* Map the flash resident part */ 892 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz; 893 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 894 create_pgd_mapping(pgdir, va, 895 kernel_map.xiprom + (va - kernel_map.virt_addr), 896 PMD_SIZE, PAGE_KERNEL_EXEC); 897 898 /* Map the data in RAM */ 899 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size; 900 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) 901 create_pgd_mapping(pgdir, va, 902 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), 903 PMD_SIZE, PAGE_KERNEL); 904 } 905 #else 906 static void __init create_kernel_page_table(pgd_t *pgdir, bool early) 907 { 908 uintptr_t va, end_va; 909 910 end_va = kernel_map.virt_addr + kernel_map.size; 911 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 912 create_pgd_mapping(pgdir, va, 913 kernel_map.phys_addr + (va - kernel_map.virt_addr), 914 PMD_SIZE, 915 early ? 916 PAGE_KERNEL_EXEC : pgprot_from_va(va)); 917 } 918 #endif 919 920 /* 921 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel, 922 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR 923 * entry. 924 */ 925 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va, 926 uintptr_t dtb_pa) 927 { 928 #ifndef CONFIG_BUILTIN_DTB 929 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); 930 931 /* Make sure the fdt fixmap address is always aligned on PMD size */ 932 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE)); 933 934 /* In 32-bit only, the fdt lies in its own PGD */ 935 if (!IS_ENABLED(CONFIG_64BIT)) { 936 create_pgd_mapping(early_pg_dir, fix_fdt_va, 937 pa, MAX_FDT_SIZE, PAGE_KERNEL); 938 } else { 939 create_pmd_mapping(fixmap_pmd, fix_fdt_va, 940 pa, PMD_SIZE, PAGE_KERNEL); 941 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE, 942 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); 943 } 944 945 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1)); 946 #else 947 /* 948 * For 64-bit kernel, __va can't be used since it would return a linear 949 * mapping address whereas dtb_early_va will be used before 950 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the 951 * kernel is mapped in the linear mapping, that makes no difference. 952 */ 953 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa)); 954 #endif 955 956 dtb_early_pa = dtb_pa; 957 } 958 959 /* 960 * MMU is not enabled, the page tables are allocated directly using 961 * early_pmd/pud/p4d and the address returned is the physical one. 962 */ 963 static void __init pt_ops_set_early(void) 964 { 965 pt_ops.alloc_pte = alloc_pte_early; 966 pt_ops.get_pte_virt = get_pte_virt_early; 967 #ifndef __PAGETABLE_PMD_FOLDED 968 pt_ops.alloc_pmd = alloc_pmd_early; 969 pt_ops.get_pmd_virt = get_pmd_virt_early; 970 pt_ops.alloc_pud = alloc_pud_early; 971 pt_ops.get_pud_virt = get_pud_virt_early; 972 pt_ops.alloc_p4d = alloc_p4d_early; 973 pt_ops.get_p4d_virt = get_p4d_virt_early; 974 #endif 975 } 976 977 /* 978 * MMU is enabled but page table setup is not complete yet. 979 * fixmap page table alloc functions must be used as a means to temporarily 980 * map the allocated physical pages since the linear mapping does not exist yet. 981 * 982 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va, 983 * but it will be used as described above. 984 */ 985 static void __init pt_ops_set_fixmap(void) 986 { 987 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap); 988 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap); 989 #ifndef __PAGETABLE_PMD_FOLDED 990 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap); 991 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap); 992 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap); 993 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap); 994 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap); 995 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap); 996 #endif 997 } 998 999 /* 1000 * MMU is enabled and page table setup is complete, so from now, we can use 1001 * generic page allocation functions to setup page table. 1002 */ 1003 static void __init pt_ops_set_late(void) 1004 { 1005 pt_ops.alloc_pte = alloc_pte_late; 1006 pt_ops.get_pte_virt = get_pte_virt_late; 1007 #ifndef __PAGETABLE_PMD_FOLDED 1008 pt_ops.alloc_pmd = alloc_pmd_late; 1009 pt_ops.get_pmd_virt = get_pmd_virt_late; 1010 pt_ops.alloc_pud = alloc_pud_late; 1011 pt_ops.get_pud_virt = get_pud_virt_late; 1012 pt_ops.alloc_p4d = alloc_p4d_late; 1013 pt_ops.get_p4d_virt = get_p4d_virt_late; 1014 #endif 1015 } 1016 1017 #ifdef CONFIG_RANDOMIZE_BASE 1018 extern bool __init __pi_set_nokaslr_from_cmdline(uintptr_t dtb_pa); 1019 extern u64 __init __pi_get_kaslr_seed(uintptr_t dtb_pa); 1020 1021 static int __init print_nokaslr(char *p) 1022 { 1023 pr_info("Disabled KASLR"); 1024 return 0; 1025 } 1026 early_param("nokaslr", print_nokaslr); 1027 1028 unsigned long kaslr_offset(void) 1029 { 1030 return kernel_map.virt_offset; 1031 } 1032 #endif 1033 1034 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1035 { 1036 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1037 1038 #ifdef CONFIG_RANDOMIZE_BASE 1039 if (!__pi_set_nokaslr_from_cmdline(dtb_pa)) { 1040 u64 kaslr_seed = __pi_get_kaslr_seed(dtb_pa); 1041 u32 kernel_size = (uintptr_t)(&_end) - (uintptr_t)(&_start); 1042 u32 nr_pos; 1043 1044 /* 1045 * Compute the number of positions available: we are limited 1046 * by the early page table that only has one PUD and we must 1047 * be aligned on PMD_SIZE. 1048 */ 1049 nr_pos = (PUD_SIZE - kernel_size) / PMD_SIZE; 1050 1051 kernel_map.virt_offset = (kaslr_seed % nr_pos) * PMD_SIZE; 1052 } 1053 #endif 1054 1055 kernel_map.virt_addr = KERNEL_LINK_ADDR + kernel_map.virt_offset; 1056 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1057 1058 #ifdef CONFIG_XIP_KERNEL 1059 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; 1060 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); 1061 1062 phys_ram_base = CONFIG_PHYS_RAM_BASE; 1063 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; 1064 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); 1065 1066 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; 1067 #else 1068 kernel_map.phys_addr = (uintptr_t)(&_start); 1069 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1070 #endif 1071 1072 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 1073 set_satp_mode(dtb_pa); 1074 #endif 1075 1076 /* 1077 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1078 * where we have the system memory layout: this allows us to align 1079 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1080 * for the linear mapping. This is only possible because the kernel 1081 * mapping lies outside the linear mapping. 1082 * In 32-bit however, as the kernel resides in the linear mapping, 1083 * setup_vm_final can not change the mapping established here, 1084 * otherwise the same kernel addresses would get mapped to different 1085 * physical addresses (if the start of dram is different from the 1086 * kernel physical address start). 1087 */ 1088 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1089 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1090 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1091 1092 /* 1093 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit 1094 * kernel, whereas for 64-bit kernel, the end of the virtual address 1095 * space is occupied by the modules/BPF/kernel mappings which reduces 1096 * the available size of the linear mapping. 1097 */ 1098 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); 1099 1100 /* Sanity check alignment and size */ 1101 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1102 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1103 1104 #ifdef CONFIG_64BIT 1105 /* 1106 * The last 4K bytes of the addressable memory can not be mapped because 1107 * of IS_ERR_VALUE macro. 1108 */ 1109 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1110 #endif 1111 1112 #ifdef CONFIG_RELOCATABLE 1113 /* 1114 * Early page table uses only one PUD, which makes it possible 1115 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1116 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1117 * since a part of the kernel would not get mapped. 1118 */ 1119 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1120 relocate_kernel(); 1121 #endif 1122 1123 apply_early_boot_alternatives(); 1124 pt_ops_set_early(); 1125 1126 /* Setup early PGD for fixmap */ 1127 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1128 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1129 1130 #ifndef __PAGETABLE_PMD_FOLDED 1131 /* Setup fixmap P4D and PUD */ 1132 if (pgtable_l5_enabled) 1133 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1134 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1135 /* Setup fixmap PUD and PMD */ 1136 if (pgtable_l4_enabled) 1137 create_pud_mapping(fixmap_pud, FIXADDR_START, 1138 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1139 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1140 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1141 /* Setup trampoline PGD and PMD */ 1142 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1143 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1144 if (pgtable_l5_enabled) 1145 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1146 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1147 if (pgtable_l4_enabled) 1148 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1149 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1150 #ifdef CONFIG_XIP_KERNEL 1151 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1152 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); 1153 #else 1154 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1155 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1156 #endif 1157 #else 1158 /* Setup trampoline PGD */ 1159 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1160 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1161 #endif 1162 1163 /* 1164 * Setup early PGD covering entire kernel which will allow 1165 * us to reach paging_init(). We map all memory banks later 1166 * in setup_vm_final() below. 1167 */ 1168 create_kernel_page_table(early_pg_dir, true); 1169 1170 /* Setup early mapping for FDT early scan */ 1171 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1172 1173 /* 1174 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1175 * range can not span multiple pmds. 1176 */ 1177 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1178 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1179 1180 #ifndef __PAGETABLE_PMD_FOLDED 1181 /* 1182 * Early ioremap fixmap is already created as it lies within first 2MB 1183 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1184 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1185 * the user if not. 1186 */ 1187 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1188 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1189 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1190 WARN_ON(1); 1191 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1192 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1193 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1194 fix_to_virt(FIX_BTMAP_BEGIN)); 1195 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1196 fix_to_virt(FIX_BTMAP_END)); 1197 1198 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1199 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1200 } 1201 #endif 1202 1203 pt_ops_set_fixmap(); 1204 } 1205 1206 static void __init create_linear_mapping_range(phys_addr_t start, 1207 phys_addr_t end, 1208 uintptr_t fixed_map_size) 1209 { 1210 phys_addr_t pa; 1211 uintptr_t va, map_size; 1212 1213 for (pa = start; pa < end; pa += map_size) { 1214 va = (uintptr_t)__va(pa); 1215 map_size = fixed_map_size ? fixed_map_size : 1216 best_map_size(pa, va, end - pa); 1217 1218 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1219 pgprot_from_va(va)); 1220 } 1221 } 1222 1223 static void __init create_linear_mapping_page_table(void) 1224 { 1225 phys_addr_t start, end; 1226 phys_addr_t kfence_pool __maybe_unused; 1227 u64 i; 1228 1229 #ifdef CONFIG_STRICT_KERNEL_RWX 1230 phys_addr_t ktext_start = __pa_symbol(_start); 1231 phys_addr_t ktext_size = __init_data_begin - _start; 1232 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1233 phys_addr_t krodata_size = _data - __start_rodata; 1234 1235 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1236 memblock_mark_nomap(ktext_start, ktext_size); 1237 memblock_mark_nomap(krodata_start, krodata_size); 1238 #endif 1239 1240 #ifdef CONFIG_KFENCE 1241 /* 1242 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1243 * before we setup the linear mapping so that we avoid using hugepages 1244 * for this region. 1245 */ 1246 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1247 BUG_ON(!kfence_pool); 1248 1249 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1250 __kfence_pool = __va(kfence_pool); 1251 #endif 1252 1253 /* Map all memory banks in the linear mapping */ 1254 for_each_mem_range(i, &start, &end) { 1255 if (start >= end) 1256 break; 1257 if (start <= __pa(PAGE_OFFSET) && 1258 __pa(PAGE_OFFSET) < end) 1259 start = __pa(PAGE_OFFSET); 1260 if (end >= __pa(PAGE_OFFSET) + memory_limit) 1261 end = __pa(PAGE_OFFSET) + memory_limit; 1262 1263 create_linear_mapping_range(start, end, 0); 1264 } 1265 1266 #ifdef CONFIG_STRICT_KERNEL_RWX 1267 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0); 1268 create_linear_mapping_range(krodata_start, 1269 krodata_start + krodata_size, 0); 1270 1271 memblock_clear_nomap(ktext_start, ktext_size); 1272 memblock_clear_nomap(krodata_start, krodata_size); 1273 #endif 1274 1275 #ifdef CONFIG_KFENCE 1276 create_linear_mapping_range(kfence_pool, 1277 kfence_pool + KFENCE_POOL_SIZE, 1278 PAGE_SIZE); 1279 1280 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1281 #endif 1282 } 1283 1284 static void __init setup_vm_final(void) 1285 { 1286 /* Setup swapper PGD for fixmap */ 1287 #if !defined(CONFIG_64BIT) 1288 /* 1289 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1290 * directly in swapper_pg_dir in addition to the pgd entry that points 1291 * to fixmap_pte. 1292 */ 1293 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1294 1295 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1296 #endif 1297 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1298 __pa_symbol(fixmap_pgd_next), 1299 PGDIR_SIZE, PAGE_TABLE); 1300 1301 /* Map the linear mapping */ 1302 create_linear_mapping_page_table(); 1303 1304 /* Map the kernel */ 1305 if (IS_ENABLED(CONFIG_64BIT)) 1306 create_kernel_page_table(swapper_pg_dir, false); 1307 1308 #ifdef CONFIG_KASAN 1309 kasan_swapper_init(); 1310 #endif 1311 1312 /* Clear fixmap PTE and PMD mappings */ 1313 clear_fixmap(FIX_PTE); 1314 clear_fixmap(FIX_PMD); 1315 clear_fixmap(FIX_PUD); 1316 clear_fixmap(FIX_P4D); 1317 1318 /* Move to swapper page table */ 1319 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1320 local_flush_tlb_all(); 1321 1322 pt_ops_set_late(); 1323 } 1324 #else 1325 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1326 { 1327 dtb_early_va = (void *)dtb_pa; 1328 dtb_early_pa = dtb_pa; 1329 } 1330 1331 static inline void setup_vm_final(void) 1332 { 1333 } 1334 #endif /* CONFIG_MMU */ 1335 1336 /* Reserve 128M low memory by default for swiotlb buffer */ 1337 #define DEFAULT_CRASH_KERNEL_LOW_SIZE (128UL << 20) 1338 1339 static int __init reserve_crashkernel_low(unsigned long long low_size) 1340 { 1341 unsigned long long low_base; 1342 1343 low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit); 1344 if (!low_base) { 1345 pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size); 1346 return -ENOMEM; 1347 } 1348 1349 pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n", 1350 low_base, low_base + low_size, low_size >> 20); 1351 1352 crashk_low_res.start = low_base; 1353 crashk_low_res.end = low_base + low_size - 1; 1354 1355 return 0; 1356 } 1357 1358 /* 1359 * reserve_crashkernel() - reserves memory for crash kernel 1360 * 1361 * This function reserves memory area given in "crashkernel=" kernel command 1362 * line parameter. The memory reserved is used by dump capture kernel when 1363 * primary kernel is crashing. 1364 */ 1365 static void __init reserve_crashkernel(void) 1366 { 1367 unsigned long long crash_base = 0; 1368 unsigned long long crash_size = 0; 1369 unsigned long long crash_low_size = 0; 1370 unsigned long search_start = memblock_start_of_DRAM(); 1371 unsigned long search_end = (unsigned long)dma32_phys_limit; 1372 char *cmdline = boot_command_line; 1373 bool fixed_base = false; 1374 bool high = false; 1375 1376 int ret = 0; 1377 1378 if (!IS_ENABLED(CONFIG_KEXEC_CORE)) 1379 return; 1380 /* 1381 * Don't reserve a region for a crash kernel on a crash kernel 1382 * since it doesn't make much sense and we have limited memory 1383 * resources. 1384 */ 1385 if (is_kdump_kernel()) { 1386 pr_info("crashkernel: ignoring reservation request\n"); 1387 return; 1388 } 1389 1390 ret = parse_crashkernel(cmdline, memblock_phys_mem_size(), 1391 &crash_size, &crash_base); 1392 if (ret == -ENOENT) { 1393 /* Fallback to crashkernel=X,[high,low] */ 1394 ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base); 1395 if (ret || !crash_size) 1396 return; 1397 1398 /* 1399 * crashkernel=Y,low is valid only when crashkernel=X,high 1400 * is passed. 1401 */ 1402 ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base); 1403 if (ret == -ENOENT) 1404 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; 1405 else if (ret) 1406 return; 1407 1408 search_start = (unsigned long)dma32_phys_limit; 1409 search_end = memblock_end_of_DRAM(); 1410 high = true; 1411 } else if (ret || !crash_size) { 1412 /* Invalid argument value specified */ 1413 return; 1414 } 1415 1416 crash_size = PAGE_ALIGN(crash_size); 1417 1418 if (crash_base) { 1419 fixed_base = true; 1420 search_start = crash_base; 1421 search_end = crash_base + crash_size; 1422 } 1423 1424 /* 1425 * Current riscv boot protocol requires 2MB alignment for 1426 * RV64 and 4MB alignment for RV32 (hugepage size) 1427 * 1428 * Try to alloc from 32bit addressible physical memory so that 1429 * swiotlb can work on the crash kernel. 1430 */ 1431 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1432 search_start, search_end); 1433 if (crash_base == 0) { 1434 /* 1435 * For crashkernel=size[KMG]@offset[KMG], print out failure 1436 * message if can't reserve the specified region. 1437 */ 1438 if (fixed_base) { 1439 pr_warn("crashkernel: allocating failed with given size@offset\n"); 1440 return; 1441 } 1442 1443 if (high) { 1444 /* 1445 * For crashkernel=size[KMG],high, if the first attempt was 1446 * for high memory, fall back to low memory. 1447 */ 1448 search_start = memblock_start_of_DRAM(); 1449 search_end = (unsigned long)dma32_phys_limit; 1450 } else { 1451 /* 1452 * For crashkernel=size[KMG], if the first attempt was for 1453 * low memory, fall back to high memory, the minimum required 1454 * low memory will be reserved later. 1455 */ 1456 search_start = (unsigned long)dma32_phys_limit; 1457 search_end = memblock_end_of_DRAM(); 1458 crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; 1459 } 1460 1461 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1462 search_start, search_end); 1463 if (crash_base == 0) { 1464 pr_warn("crashkernel: couldn't allocate %lldKB\n", 1465 crash_size >> 10); 1466 return; 1467 } 1468 } 1469 1470 if ((crash_base >= dma32_phys_limit) && crash_low_size && 1471 reserve_crashkernel_low(crash_low_size)) { 1472 memblock_phys_free(crash_base, crash_size); 1473 return; 1474 } 1475 1476 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", 1477 crash_base, crash_base + crash_size, crash_size >> 20); 1478 1479 crashk_res.start = crash_base; 1480 crashk_res.end = crash_base + crash_size - 1; 1481 } 1482 1483 void __init paging_init(void) 1484 { 1485 setup_bootmem(); 1486 setup_vm_final(); 1487 1488 /* Depend on that Linear Mapping is ready */ 1489 memblock_allow_resize(); 1490 } 1491 1492 void __init misc_mem_init(void) 1493 { 1494 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1495 arch_numa_init(); 1496 sparse_init(); 1497 zone_sizes_init(); 1498 reserve_crashkernel(); 1499 memblock_dump_all(); 1500 } 1501 1502 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1503 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1504 struct vmem_altmap *altmap) 1505 { 1506 return vmemmap_populate_basepages(start, end, node, NULL); 1507 } 1508 #endif 1509 1510 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1511 /* 1512 * Pre-allocates page-table pages for a specific area in the kernel 1513 * page-table. Only the level which needs to be synchronized between 1514 * all page-tables is allocated because the synchronization can be 1515 * expensive. 1516 */ 1517 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1518 const char *area) 1519 { 1520 unsigned long addr; 1521 const char *lvl; 1522 1523 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1524 pgd_t *pgd = pgd_offset_k(addr); 1525 p4d_t *p4d; 1526 pud_t *pud; 1527 pmd_t *pmd; 1528 1529 lvl = "p4d"; 1530 p4d = p4d_alloc(&init_mm, pgd, addr); 1531 if (!p4d) 1532 goto failed; 1533 1534 if (pgtable_l5_enabled) 1535 continue; 1536 1537 lvl = "pud"; 1538 pud = pud_alloc(&init_mm, p4d, addr); 1539 if (!pud) 1540 goto failed; 1541 1542 if (pgtable_l4_enabled) 1543 continue; 1544 1545 lvl = "pmd"; 1546 pmd = pmd_alloc(&init_mm, pud, addr); 1547 if (!pmd) 1548 goto failed; 1549 } 1550 return; 1551 1552 failed: 1553 /* 1554 * The pages have to be there now or they will be missing in 1555 * process page-tables later. 1556 */ 1557 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1558 } 1559 1560 void __init pgtable_cache_init(void) 1561 { 1562 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1563 if (IS_ENABLED(CONFIG_MODULES)) 1564 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1565 } 1566 #endif 1567