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 unsigned long vaddr; 363 364 vaddr = __get_free_page(GFP_KERNEL); 365 BUG_ON(!vaddr || !pgtable_pte_page_ctor(virt_to_page((void *)vaddr))); 366 367 return __pa(vaddr); 368 } 369 370 static void __init create_pte_mapping(pte_t *ptep, 371 uintptr_t va, phys_addr_t pa, 372 phys_addr_t sz, pgprot_t prot) 373 { 374 uintptr_t pte_idx = pte_index(va); 375 376 BUG_ON(sz != PAGE_SIZE); 377 378 if (pte_none(ptep[pte_idx])) 379 ptep[pte_idx] = pfn_pte(PFN_DOWN(pa), prot); 380 } 381 382 #ifndef __PAGETABLE_PMD_FOLDED 383 384 static pmd_t trampoline_pmd[PTRS_PER_PMD] __page_aligned_bss; 385 static pmd_t fixmap_pmd[PTRS_PER_PMD] __page_aligned_bss; 386 static pmd_t early_pmd[PTRS_PER_PMD] __initdata __aligned(PAGE_SIZE); 387 388 #ifdef CONFIG_XIP_KERNEL 389 #define trampoline_pmd ((pmd_t *)XIP_FIXUP(trampoline_pmd)) 390 #define fixmap_pmd ((pmd_t *)XIP_FIXUP(fixmap_pmd)) 391 #define early_pmd ((pmd_t *)XIP_FIXUP(early_pmd)) 392 #endif /* CONFIG_XIP_KERNEL */ 393 394 static p4d_t trampoline_p4d[PTRS_PER_P4D] __page_aligned_bss; 395 static p4d_t fixmap_p4d[PTRS_PER_P4D] __page_aligned_bss; 396 static p4d_t early_p4d[PTRS_PER_P4D] __initdata __aligned(PAGE_SIZE); 397 398 #ifdef CONFIG_XIP_KERNEL 399 #define trampoline_p4d ((p4d_t *)XIP_FIXUP(trampoline_p4d)) 400 #define fixmap_p4d ((p4d_t *)XIP_FIXUP(fixmap_p4d)) 401 #define early_p4d ((p4d_t *)XIP_FIXUP(early_p4d)) 402 #endif /* CONFIG_XIP_KERNEL */ 403 404 static pud_t trampoline_pud[PTRS_PER_PUD] __page_aligned_bss; 405 static pud_t fixmap_pud[PTRS_PER_PUD] __page_aligned_bss; 406 static pud_t early_pud[PTRS_PER_PUD] __initdata __aligned(PAGE_SIZE); 407 408 #ifdef CONFIG_XIP_KERNEL 409 #define trampoline_pud ((pud_t *)XIP_FIXUP(trampoline_pud)) 410 #define fixmap_pud ((pud_t *)XIP_FIXUP(fixmap_pud)) 411 #define early_pud ((pud_t *)XIP_FIXUP(early_pud)) 412 #endif /* CONFIG_XIP_KERNEL */ 413 414 static pmd_t *__init get_pmd_virt_early(phys_addr_t pa) 415 { 416 /* Before MMU is enabled */ 417 return (pmd_t *)((uintptr_t)pa); 418 } 419 420 static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa) 421 { 422 clear_fixmap(FIX_PMD); 423 return (pmd_t *)set_fixmap_offset(FIX_PMD, pa); 424 } 425 426 static pmd_t *__init get_pmd_virt_late(phys_addr_t pa) 427 { 428 return (pmd_t *) __va(pa); 429 } 430 431 static phys_addr_t __init alloc_pmd_early(uintptr_t va) 432 { 433 BUG_ON((va - kernel_map.virt_addr) >> PUD_SHIFT); 434 435 return (uintptr_t)early_pmd; 436 } 437 438 static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va) 439 { 440 return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE); 441 } 442 443 static phys_addr_t __init alloc_pmd_late(uintptr_t va) 444 { 445 unsigned long vaddr; 446 447 vaddr = __get_free_page(GFP_KERNEL); 448 BUG_ON(!vaddr || !pgtable_pmd_page_ctor(virt_to_page((void *)vaddr))); 449 450 return __pa(vaddr); 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 (!(pa & (PGDIR_SIZE - 1)) && !(va & (PGDIR_SIZE - 1)) && size >= PGDIR_SIZE) 672 return PGDIR_SIZE; 673 674 if (!(pa & (P4D_SIZE - 1)) && !(va & (P4D_SIZE - 1)) && size >= P4D_SIZE) 675 return P4D_SIZE; 676 677 if (!(pa & (PUD_SIZE - 1)) && !(va & (PUD_SIZE - 1)) && size >= PUD_SIZE) 678 return PUD_SIZE; 679 680 if (!(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 debug_checkwx(); 727 } 728 #else 729 static __init pgprot_t pgprot_from_va(uintptr_t va) 730 { 731 if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va)) 732 return PAGE_KERNEL; 733 734 return PAGE_KERNEL_EXEC; 735 } 736 #endif /* CONFIG_STRICT_KERNEL_RWX */ 737 738 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 739 u64 __pi_set_satp_mode_from_cmdline(uintptr_t dtb_pa); 740 741 static void __init disable_pgtable_l5(void) 742 { 743 pgtable_l5_enabled = false; 744 kernel_map.page_offset = PAGE_OFFSET_L4; 745 satp_mode = SATP_MODE_48; 746 } 747 748 static void __init disable_pgtable_l4(void) 749 { 750 pgtable_l4_enabled = false; 751 kernel_map.page_offset = PAGE_OFFSET_L3; 752 satp_mode = SATP_MODE_39; 753 } 754 755 static int __init print_no4lvl(char *p) 756 { 757 pr_info("Disabled 4-level and 5-level paging"); 758 return 0; 759 } 760 early_param("no4lvl", print_no4lvl); 761 762 static int __init print_no5lvl(char *p) 763 { 764 pr_info("Disabled 5-level paging"); 765 return 0; 766 } 767 early_param("no5lvl", print_no5lvl); 768 769 /* 770 * There is a simple way to determine if 4-level is supported by the 771 * underlying hardware: establish 1:1 mapping in 4-level page table mode 772 * then read SATP to see if the configuration was taken into account 773 * meaning sv48 is supported. 774 */ 775 static __init void set_satp_mode(uintptr_t dtb_pa) 776 { 777 u64 identity_satp, hw_satp; 778 uintptr_t set_satp_mode_pmd = ((unsigned long)set_satp_mode) & PMD_MASK; 779 u64 satp_mode_cmdline = __pi_set_satp_mode_from_cmdline(dtb_pa); 780 781 if (satp_mode_cmdline == SATP_MODE_57) { 782 disable_pgtable_l5(); 783 } else if (satp_mode_cmdline == SATP_MODE_48) { 784 disable_pgtable_l5(); 785 disable_pgtable_l4(); 786 return; 787 } 788 789 create_p4d_mapping(early_p4d, 790 set_satp_mode_pmd, (uintptr_t)early_pud, 791 P4D_SIZE, PAGE_TABLE); 792 create_pud_mapping(early_pud, 793 set_satp_mode_pmd, (uintptr_t)early_pmd, 794 PUD_SIZE, PAGE_TABLE); 795 /* Handle the case where set_satp_mode straddles 2 PMDs */ 796 create_pmd_mapping(early_pmd, 797 set_satp_mode_pmd, set_satp_mode_pmd, 798 PMD_SIZE, PAGE_KERNEL_EXEC); 799 create_pmd_mapping(early_pmd, 800 set_satp_mode_pmd + PMD_SIZE, 801 set_satp_mode_pmd + PMD_SIZE, 802 PMD_SIZE, PAGE_KERNEL_EXEC); 803 retry: 804 create_pgd_mapping(early_pg_dir, 805 set_satp_mode_pmd, 806 pgtable_l5_enabled ? 807 (uintptr_t)early_p4d : (uintptr_t)early_pud, 808 PGDIR_SIZE, PAGE_TABLE); 809 810 identity_satp = PFN_DOWN((uintptr_t)&early_pg_dir) | satp_mode; 811 812 local_flush_tlb_all(); 813 csr_write(CSR_SATP, identity_satp); 814 hw_satp = csr_swap(CSR_SATP, 0ULL); 815 local_flush_tlb_all(); 816 817 if (hw_satp != identity_satp) { 818 if (pgtable_l5_enabled) { 819 disable_pgtable_l5(); 820 memset(early_pg_dir, 0, PAGE_SIZE); 821 goto retry; 822 } 823 disable_pgtable_l4(); 824 } 825 826 memset(early_pg_dir, 0, PAGE_SIZE); 827 memset(early_p4d, 0, PAGE_SIZE); 828 memset(early_pud, 0, PAGE_SIZE); 829 memset(early_pmd, 0, PAGE_SIZE); 830 } 831 #endif 832 833 /* 834 * setup_vm() is called from head.S with MMU-off. 835 * 836 * Following requirements should be honoured for setup_vm() to work 837 * correctly: 838 * 1) It should use PC-relative addressing for accessing kernel symbols. 839 * To achieve this we always use GCC cmodel=medany. 840 * 2) The compiler instrumentation for FTRACE will not work for setup_vm() 841 * so disable compiler instrumentation when FTRACE is enabled. 842 * 843 * Currently, the above requirements are honoured by using custom CFLAGS 844 * for init.o in mm/Makefile. 845 */ 846 847 #ifndef __riscv_cmodel_medany 848 #error "setup_vm() is called from head.S before relocate so it should not use absolute addressing." 849 #endif 850 851 #ifdef CONFIG_RELOCATABLE 852 extern unsigned long __rela_dyn_start, __rela_dyn_end; 853 854 static void __init relocate_kernel(void) 855 { 856 Elf64_Rela *rela = (Elf64_Rela *)&__rela_dyn_start; 857 /* 858 * This holds the offset between the linked virtual address and the 859 * relocated virtual address. 860 */ 861 uintptr_t reloc_offset = kernel_map.virt_addr - KERNEL_LINK_ADDR; 862 /* 863 * This holds the offset between kernel linked virtual address and 864 * physical address. 865 */ 866 uintptr_t va_kernel_link_pa_offset = KERNEL_LINK_ADDR - kernel_map.phys_addr; 867 868 for ( ; rela < (Elf64_Rela *)&__rela_dyn_end; rela++) { 869 Elf64_Addr addr = (rela->r_offset - va_kernel_link_pa_offset); 870 Elf64_Addr relocated_addr = rela->r_addend; 871 872 if (rela->r_info != R_RISCV_RELATIVE) 873 continue; 874 875 /* 876 * Make sure to not relocate vdso symbols like rt_sigreturn 877 * which are linked from the address 0 in vmlinux since 878 * vdso symbol addresses are actually used as an offset from 879 * mm->context.vdso in VDSO_OFFSET macro. 880 */ 881 if (relocated_addr >= KERNEL_LINK_ADDR) 882 relocated_addr += reloc_offset; 883 884 *(Elf64_Addr *)addr = relocated_addr; 885 } 886 } 887 #endif /* CONFIG_RELOCATABLE */ 888 889 #ifdef CONFIG_XIP_KERNEL 890 static void __init create_kernel_page_table(pgd_t *pgdir, 891 __always_unused bool early) 892 { 893 uintptr_t va, end_va; 894 895 /* Map the flash resident part */ 896 end_va = kernel_map.virt_addr + kernel_map.xiprom_sz; 897 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 898 create_pgd_mapping(pgdir, va, 899 kernel_map.xiprom + (va - kernel_map.virt_addr), 900 PMD_SIZE, PAGE_KERNEL_EXEC); 901 902 /* Map the data in RAM */ 903 end_va = kernel_map.virt_addr + XIP_OFFSET + kernel_map.size; 904 for (va = kernel_map.virt_addr + XIP_OFFSET; va < end_va; va += PMD_SIZE) 905 create_pgd_mapping(pgdir, va, 906 kernel_map.phys_addr + (va - (kernel_map.virt_addr + XIP_OFFSET)), 907 PMD_SIZE, PAGE_KERNEL); 908 } 909 #else 910 static void __init create_kernel_page_table(pgd_t *pgdir, bool early) 911 { 912 uintptr_t va, end_va; 913 914 end_va = kernel_map.virt_addr + kernel_map.size; 915 for (va = kernel_map.virt_addr; va < end_va; va += PMD_SIZE) 916 create_pgd_mapping(pgdir, va, 917 kernel_map.phys_addr + (va - kernel_map.virt_addr), 918 PMD_SIZE, 919 early ? 920 PAGE_KERNEL_EXEC : pgprot_from_va(va)); 921 } 922 #endif 923 924 /* 925 * Setup a 4MB mapping that encompasses the device tree: for 64-bit kernel, 926 * this means 2 PMD entries whereas for 32-bit kernel, this is only 1 PGDIR 927 * entry. 928 */ 929 static void __init create_fdt_early_page_table(uintptr_t fix_fdt_va, 930 uintptr_t dtb_pa) 931 { 932 #ifndef CONFIG_BUILTIN_DTB 933 uintptr_t pa = dtb_pa & ~(PMD_SIZE - 1); 934 935 /* Make sure the fdt fixmap address is always aligned on PMD size */ 936 BUILD_BUG_ON(FIX_FDT % (PMD_SIZE / PAGE_SIZE)); 937 938 /* In 32-bit only, the fdt lies in its own PGD */ 939 if (!IS_ENABLED(CONFIG_64BIT)) { 940 create_pgd_mapping(early_pg_dir, fix_fdt_va, 941 pa, MAX_FDT_SIZE, PAGE_KERNEL); 942 } else { 943 create_pmd_mapping(fixmap_pmd, fix_fdt_va, 944 pa, PMD_SIZE, PAGE_KERNEL); 945 create_pmd_mapping(fixmap_pmd, fix_fdt_va + PMD_SIZE, 946 pa + PMD_SIZE, PMD_SIZE, PAGE_KERNEL); 947 } 948 949 dtb_early_va = (void *)fix_fdt_va + (dtb_pa & (PMD_SIZE - 1)); 950 #else 951 /* 952 * For 64-bit kernel, __va can't be used since it would return a linear 953 * mapping address whereas dtb_early_va will be used before 954 * setup_vm_final installs the linear mapping. For 32-bit kernel, as the 955 * kernel is mapped in the linear mapping, that makes no difference. 956 */ 957 dtb_early_va = kernel_mapping_pa_to_va(XIP_FIXUP(dtb_pa)); 958 #endif 959 960 dtb_early_pa = dtb_pa; 961 } 962 963 /* 964 * MMU is not enabled, the page tables are allocated directly using 965 * early_pmd/pud/p4d and the address returned is the physical one. 966 */ 967 static void __init pt_ops_set_early(void) 968 { 969 pt_ops.alloc_pte = alloc_pte_early; 970 pt_ops.get_pte_virt = get_pte_virt_early; 971 #ifndef __PAGETABLE_PMD_FOLDED 972 pt_ops.alloc_pmd = alloc_pmd_early; 973 pt_ops.get_pmd_virt = get_pmd_virt_early; 974 pt_ops.alloc_pud = alloc_pud_early; 975 pt_ops.get_pud_virt = get_pud_virt_early; 976 pt_ops.alloc_p4d = alloc_p4d_early; 977 pt_ops.get_p4d_virt = get_p4d_virt_early; 978 #endif 979 } 980 981 /* 982 * MMU is enabled but page table setup is not complete yet. 983 * fixmap page table alloc functions must be used as a means to temporarily 984 * map the allocated physical pages since the linear mapping does not exist yet. 985 * 986 * Note that this is called with MMU disabled, hence kernel_mapping_pa_to_va, 987 * but it will be used as described above. 988 */ 989 static void __init pt_ops_set_fixmap(void) 990 { 991 pt_ops.alloc_pte = kernel_mapping_pa_to_va(alloc_pte_fixmap); 992 pt_ops.get_pte_virt = kernel_mapping_pa_to_va(get_pte_virt_fixmap); 993 #ifndef __PAGETABLE_PMD_FOLDED 994 pt_ops.alloc_pmd = kernel_mapping_pa_to_va(alloc_pmd_fixmap); 995 pt_ops.get_pmd_virt = kernel_mapping_pa_to_va(get_pmd_virt_fixmap); 996 pt_ops.alloc_pud = kernel_mapping_pa_to_va(alloc_pud_fixmap); 997 pt_ops.get_pud_virt = kernel_mapping_pa_to_va(get_pud_virt_fixmap); 998 pt_ops.alloc_p4d = kernel_mapping_pa_to_va(alloc_p4d_fixmap); 999 pt_ops.get_p4d_virt = kernel_mapping_pa_to_va(get_p4d_virt_fixmap); 1000 #endif 1001 } 1002 1003 /* 1004 * MMU is enabled and page table setup is complete, so from now, we can use 1005 * generic page allocation functions to setup page table. 1006 */ 1007 static void __init pt_ops_set_late(void) 1008 { 1009 pt_ops.alloc_pte = alloc_pte_late; 1010 pt_ops.get_pte_virt = get_pte_virt_late; 1011 #ifndef __PAGETABLE_PMD_FOLDED 1012 pt_ops.alloc_pmd = alloc_pmd_late; 1013 pt_ops.get_pmd_virt = get_pmd_virt_late; 1014 pt_ops.alloc_pud = alloc_pud_late; 1015 pt_ops.get_pud_virt = get_pud_virt_late; 1016 pt_ops.alloc_p4d = alloc_p4d_late; 1017 pt_ops.get_p4d_virt = get_p4d_virt_late; 1018 #endif 1019 } 1020 1021 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1022 { 1023 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1024 1025 kernel_map.virt_addr = KERNEL_LINK_ADDR; 1026 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1027 1028 #ifdef CONFIG_XIP_KERNEL 1029 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; 1030 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); 1031 1032 phys_ram_base = CONFIG_PHYS_RAM_BASE; 1033 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; 1034 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); 1035 1036 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; 1037 #else 1038 kernel_map.phys_addr = (uintptr_t)(&_start); 1039 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1040 #endif 1041 1042 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 1043 set_satp_mode(dtb_pa); 1044 #endif 1045 1046 /* 1047 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1048 * where we have the system memory layout: this allows us to align 1049 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1050 * for the linear mapping. This is only possible because the kernel 1051 * mapping lies outside the linear mapping. 1052 * In 32-bit however, as the kernel resides in the linear mapping, 1053 * setup_vm_final can not change the mapping established here, 1054 * otherwise the same kernel addresses would get mapped to different 1055 * physical addresses (if the start of dram is different from the 1056 * kernel physical address start). 1057 */ 1058 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1059 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1060 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1061 1062 /* 1063 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit 1064 * kernel, whereas for 64-bit kernel, the end of the virtual address 1065 * space is occupied by the modules/BPF/kernel mappings which reduces 1066 * the available size of the linear mapping. 1067 */ 1068 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); 1069 1070 /* Sanity check alignment and size */ 1071 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1072 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1073 1074 #ifdef CONFIG_64BIT 1075 /* 1076 * The last 4K bytes of the addressable memory can not be mapped because 1077 * of IS_ERR_VALUE macro. 1078 */ 1079 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1080 #endif 1081 1082 #ifdef CONFIG_RELOCATABLE 1083 /* 1084 * Early page table uses only one PUD, which makes it possible 1085 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1086 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1087 * since a part of the kernel would not get mapped. 1088 */ 1089 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1090 relocate_kernel(); 1091 #endif 1092 1093 apply_early_boot_alternatives(); 1094 pt_ops_set_early(); 1095 1096 /* Setup early PGD for fixmap */ 1097 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1098 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1099 1100 #ifndef __PAGETABLE_PMD_FOLDED 1101 /* Setup fixmap P4D and PUD */ 1102 if (pgtable_l5_enabled) 1103 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1104 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1105 /* Setup fixmap PUD and PMD */ 1106 if (pgtable_l4_enabled) 1107 create_pud_mapping(fixmap_pud, FIXADDR_START, 1108 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1109 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1110 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1111 /* Setup trampoline PGD and PMD */ 1112 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1113 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1114 if (pgtable_l5_enabled) 1115 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1116 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1117 if (pgtable_l4_enabled) 1118 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1119 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1120 #ifdef CONFIG_XIP_KERNEL 1121 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1122 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); 1123 #else 1124 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1125 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1126 #endif 1127 #else 1128 /* Setup trampoline PGD */ 1129 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1130 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1131 #endif 1132 1133 /* 1134 * Setup early PGD covering entire kernel which will allow 1135 * us to reach paging_init(). We map all memory banks later 1136 * in setup_vm_final() below. 1137 */ 1138 create_kernel_page_table(early_pg_dir, true); 1139 1140 /* Setup early mapping for FDT early scan */ 1141 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1142 1143 /* 1144 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1145 * range can not span multiple pmds. 1146 */ 1147 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1148 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1149 1150 #ifndef __PAGETABLE_PMD_FOLDED 1151 /* 1152 * Early ioremap fixmap is already created as it lies within first 2MB 1153 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1154 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1155 * the user if not. 1156 */ 1157 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1158 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1159 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1160 WARN_ON(1); 1161 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1162 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1163 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1164 fix_to_virt(FIX_BTMAP_BEGIN)); 1165 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1166 fix_to_virt(FIX_BTMAP_END)); 1167 1168 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1169 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1170 } 1171 #endif 1172 1173 pt_ops_set_fixmap(); 1174 } 1175 1176 static void __init create_linear_mapping_range(phys_addr_t start, 1177 phys_addr_t end, 1178 uintptr_t fixed_map_size) 1179 { 1180 phys_addr_t pa; 1181 uintptr_t va, map_size; 1182 1183 for (pa = start; pa < end; pa += map_size) { 1184 va = (uintptr_t)__va(pa); 1185 map_size = fixed_map_size ? fixed_map_size : 1186 best_map_size(pa, va, end - pa); 1187 1188 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1189 pgprot_from_va(va)); 1190 } 1191 } 1192 1193 static void __init create_linear_mapping_page_table(void) 1194 { 1195 phys_addr_t start, end; 1196 phys_addr_t kfence_pool __maybe_unused; 1197 u64 i; 1198 1199 #ifdef CONFIG_STRICT_KERNEL_RWX 1200 phys_addr_t ktext_start = __pa_symbol(_start); 1201 phys_addr_t ktext_size = __init_data_begin - _start; 1202 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1203 phys_addr_t krodata_size = _data - __start_rodata; 1204 1205 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1206 memblock_mark_nomap(ktext_start, ktext_size); 1207 memblock_mark_nomap(krodata_start, krodata_size); 1208 #endif 1209 1210 #ifdef CONFIG_KFENCE 1211 /* 1212 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1213 * before we setup the linear mapping so that we avoid using hugepages 1214 * for this region. 1215 */ 1216 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1217 BUG_ON(!kfence_pool); 1218 1219 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1220 __kfence_pool = __va(kfence_pool); 1221 #endif 1222 1223 /* Map all memory banks in the linear mapping */ 1224 for_each_mem_range(i, &start, &end) { 1225 if (start >= end) 1226 break; 1227 if (start <= __pa(PAGE_OFFSET) && 1228 __pa(PAGE_OFFSET) < end) 1229 start = __pa(PAGE_OFFSET); 1230 if (end >= __pa(PAGE_OFFSET) + memory_limit) 1231 end = __pa(PAGE_OFFSET) + memory_limit; 1232 1233 create_linear_mapping_range(start, end, 0); 1234 } 1235 1236 #ifdef CONFIG_STRICT_KERNEL_RWX 1237 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0); 1238 create_linear_mapping_range(krodata_start, 1239 krodata_start + krodata_size, 0); 1240 1241 memblock_clear_nomap(ktext_start, ktext_size); 1242 memblock_clear_nomap(krodata_start, krodata_size); 1243 #endif 1244 1245 #ifdef CONFIG_KFENCE 1246 create_linear_mapping_range(kfence_pool, 1247 kfence_pool + KFENCE_POOL_SIZE, 1248 PAGE_SIZE); 1249 1250 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1251 #endif 1252 } 1253 1254 static void __init setup_vm_final(void) 1255 { 1256 /* Setup swapper PGD for fixmap */ 1257 #if !defined(CONFIG_64BIT) 1258 /* 1259 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1260 * directly in swapper_pg_dir in addition to the pgd entry that points 1261 * to fixmap_pte. 1262 */ 1263 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1264 1265 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1266 #endif 1267 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1268 __pa_symbol(fixmap_pgd_next), 1269 PGDIR_SIZE, PAGE_TABLE); 1270 1271 /* Map the linear mapping */ 1272 create_linear_mapping_page_table(); 1273 1274 /* Map the kernel */ 1275 if (IS_ENABLED(CONFIG_64BIT)) 1276 create_kernel_page_table(swapper_pg_dir, false); 1277 1278 #ifdef CONFIG_KASAN 1279 kasan_swapper_init(); 1280 #endif 1281 1282 /* Clear fixmap PTE and PMD mappings */ 1283 clear_fixmap(FIX_PTE); 1284 clear_fixmap(FIX_PMD); 1285 clear_fixmap(FIX_PUD); 1286 clear_fixmap(FIX_P4D); 1287 1288 /* Move to swapper page table */ 1289 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1290 local_flush_tlb_all(); 1291 1292 pt_ops_set_late(); 1293 } 1294 #else 1295 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1296 { 1297 dtb_early_va = (void *)dtb_pa; 1298 dtb_early_pa = dtb_pa; 1299 } 1300 1301 static inline void setup_vm_final(void) 1302 { 1303 } 1304 #endif /* CONFIG_MMU */ 1305 1306 /* 1307 * reserve_crashkernel() - reserves memory for crash kernel 1308 * 1309 * This function reserves memory area given in "crashkernel=" kernel command 1310 * line parameter. The memory reserved is used by dump capture kernel when 1311 * primary kernel is crashing. 1312 */ 1313 static void __init reserve_crashkernel(void) 1314 { 1315 unsigned long long crash_base = 0; 1316 unsigned long long crash_size = 0; 1317 unsigned long search_start = memblock_start_of_DRAM(); 1318 unsigned long search_end = memblock_end_of_DRAM(); 1319 1320 int ret = 0; 1321 1322 if (!IS_ENABLED(CONFIG_KEXEC_CORE)) 1323 return; 1324 /* 1325 * Don't reserve a region for a crash kernel on a crash kernel 1326 * since it doesn't make much sense and we have limited memory 1327 * resources. 1328 */ 1329 if (is_kdump_kernel()) { 1330 pr_info("crashkernel: ignoring reservation request\n"); 1331 return; 1332 } 1333 1334 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), 1335 &crash_size, &crash_base); 1336 if (ret || !crash_size) 1337 return; 1338 1339 crash_size = PAGE_ALIGN(crash_size); 1340 1341 if (crash_base) { 1342 search_start = crash_base; 1343 search_end = crash_base + crash_size; 1344 } 1345 1346 /* 1347 * Current riscv boot protocol requires 2MB alignment for 1348 * RV64 and 4MB alignment for RV32 (hugepage size) 1349 * 1350 * Try to alloc from 32bit addressible physical memory so that 1351 * swiotlb can work on the crash kernel. 1352 */ 1353 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1354 search_start, 1355 min(search_end, (unsigned long)(SZ_4G - 1))); 1356 if (crash_base == 0) { 1357 /* Try again without restricting region to 32bit addressible memory */ 1358 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1359 search_start, search_end); 1360 if (crash_base == 0) { 1361 pr_warn("crashkernel: couldn't allocate %lldKB\n", 1362 crash_size >> 10); 1363 return; 1364 } 1365 } 1366 1367 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", 1368 crash_base, crash_base + crash_size, crash_size >> 20); 1369 1370 crashk_res.start = crash_base; 1371 crashk_res.end = crash_base + crash_size - 1; 1372 } 1373 1374 void __init paging_init(void) 1375 { 1376 setup_bootmem(); 1377 setup_vm_final(); 1378 1379 /* Depend on that Linear Mapping is ready */ 1380 memblock_allow_resize(); 1381 } 1382 1383 void __init misc_mem_init(void) 1384 { 1385 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1386 arch_numa_init(); 1387 sparse_init(); 1388 zone_sizes_init(); 1389 reserve_crashkernel(); 1390 memblock_dump_all(); 1391 } 1392 1393 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1394 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1395 struct vmem_altmap *altmap) 1396 { 1397 return vmemmap_populate_basepages(start, end, node, NULL); 1398 } 1399 #endif 1400 1401 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1402 /* 1403 * Pre-allocates page-table pages for a specific area in the kernel 1404 * page-table. Only the level which needs to be synchronized between 1405 * all page-tables is allocated because the synchronization can be 1406 * expensive. 1407 */ 1408 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1409 const char *area) 1410 { 1411 unsigned long addr; 1412 const char *lvl; 1413 1414 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1415 pgd_t *pgd = pgd_offset_k(addr); 1416 p4d_t *p4d; 1417 pud_t *pud; 1418 pmd_t *pmd; 1419 1420 lvl = "p4d"; 1421 p4d = p4d_alloc(&init_mm, pgd, addr); 1422 if (!p4d) 1423 goto failed; 1424 1425 if (pgtable_l5_enabled) 1426 continue; 1427 1428 lvl = "pud"; 1429 pud = pud_alloc(&init_mm, p4d, addr); 1430 if (!pud) 1431 goto failed; 1432 1433 if (pgtable_l4_enabled) 1434 continue; 1435 1436 lvl = "pmd"; 1437 pmd = pmd_alloc(&init_mm, pud, addr); 1438 if (!pmd) 1439 goto failed; 1440 } 1441 return; 1442 1443 failed: 1444 /* 1445 * The pages have to be there now or they will be missing in 1446 * process page-tables later. 1447 */ 1448 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1449 } 1450 1451 void __init pgtable_cache_init(void) 1452 { 1453 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1454 if (IS_ENABLED(CONFIG_MODULES)) 1455 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1456 } 1457 #endif 1458