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 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1018 { 1019 pmd_t __maybe_unused fix_bmap_spmd, fix_bmap_epmd; 1020 1021 kernel_map.virt_addr = KERNEL_LINK_ADDR; 1022 kernel_map.page_offset = _AC(CONFIG_PAGE_OFFSET, UL); 1023 1024 #ifdef CONFIG_XIP_KERNEL 1025 kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; 1026 kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); 1027 1028 phys_ram_base = CONFIG_PHYS_RAM_BASE; 1029 kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; 1030 kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); 1031 1032 kernel_map.va_kernel_xip_pa_offset = kernel_map.virt_addr - kernel_map.xiprom; 1033 #else 1034 kernel_map.phys_addr = (uintptr_t)(&_start); 1035 kernel_map.size = (uintptr_t)(&_end) - kernel_map.phys_addr; 1036 #endif 1037 1038 #if defined(CONFIG_64BIT) && !defined(CONFIG_XIP_KERNEL) 1039 set_satp_mode(dtb_pa); 1040 #endif 1041 1042 /* 1043 * In 64-bit, we defer the setup of va_pa_offset to setup_bootmem, 1044 * where we have the system memory layout: this allows us to align 1045 * the physical and virtual mappings and then make use of PUD/P4D/PGD 1046 * for the linear mapping. This is only possible because the kernel 1047 * mapping lies outside the linear mapping. 1048 * In 32-bit however, as the kernel resides in the linear mapping, 1049 * setup_vm_final can not change the mapping established here, 1050 * otherwise the same kernel addresses would get mapped to different 1051 * physical addresses (if the start of dram is different from the 1052 * kernel physical address start). 1053 */ 1054 kernel_map.va_pa_offset = IS_ENABLED(CONFIG_64BIT) ? 1055 0UL : PAGE_OFFSET - kernel_map.phys_addr; 1056 kernel_map.va_kernel_pa_offset = kernel_map.virt_addr - kernel_map.phys_addr; 1057 1058 /* 1059 * The default maximal physical memory size is KERN_VIRT_SIZE for 32-bit 1060 * kernel, whereas for 64-bit kernel, the end of the virtual address 1061 * space is occupied by the modules/BPF/kernel mappings which reduces 1062 * the available size of the linear mapping. 1063 */ 1064 memory_limit = KERN_VIRT_SIZE - (IS_ENABLED(CONFIG_64BIT) ? SZ_4G : 0); 1065 1066 /* Sanity check alignment and size */ 1067 BUG_ON((PAGE_OFFSET % PGDIR_SIZE) != 0); 1068 BUG_ON((kernel_map.phys_addr % PMD_SIZE) != 0); 1069 1070 #ifdef CONFIG_64BIT 1071 /* 1072 * The last 4K bytes of the addressable memory can not be mapped because 1073 * of IS_ERR_VALUE macro. 1074 */ 1075 BUG_ON((kernel_map.virt_addr + kernel_map.size) > ADDRESS_SPACE_END - SZ_4K); 1076 #endif 1077 1078 #ifdef CONFIG_RELOCATABLE 1079 /* 1080 * Early page table uses only one PUD, which makes it possible 1081 * to map PUD_SIZE aligned on PUD_SIZE: if the relocation offset 1082 * makes the kernel cross over a PUD_SIZE boundary, raise a bug 1083 * since a part of the kernel would not get mapped. 1084 */ 1085 BUG_ON(PUD_SIZE - (kernel_map.virt_addr & (PUD_SIZE - 1)) < kernel_map.size); 1086 relocate_kernel(); 1087 #endif 1088 1089 apply_early_boot_alternatives(); 1090 pt_ops_set_early(); 1091 1092 /* Setup early PGD for fixmap */ 1093 create_pgd_mapping(early_pg_dir, FIXADDR_START, 1094 fixmap_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1095 1096 #ifndef __PAGETABLE_PMD_FOLDED 1097 /* Setup fixmap P4D and PUD */ 1098 if (pgtable_l5_enabled) 1099 create_p4d_mapping(fixmap_p4d, FIXADDR_START, 1100 (uintptr_t)fixmap_pud, P4D_SIZE, PAGE_TABLE); 1101 /* Setup fixmap PUD and PMD */ 1102 if (pgtable_l4_enabled) 1103 create_pud_mapping(fixmap_pud, FIXADDR_START, 1104 (uintptr_t)fixmap_pmd, PUD_SIZE, PAGE_TABLE); 1105 create_pmd_mapping(fixmap_pmd, FIXADDR_START, 1106 (uintptr_t)fixmap_pte, PMD_SIZE, PAGE_TABLE); 1107 /* Setup trampoline PGD and PMD */ 1108 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1109 trampoline_pgd_next, PGDIR_SIZE, PAGE_TABLE); 1110 if (pgtable_l5_enabled) 1111 create_p4d_mapping(trampoline_p4d, kernel_map.virt_addr, 1112 (uintptr_t)trampoline_pud, P4D_SIZE, PAGE_TABLE); 1113 if (pgtable_l4_enabled) 1114 create_pud_mapping(trampoline_pud, kernel_map.virt_addr, 1115 (uintptr_t)trampoline_pmd, PUD_SIZE, PAGE_TABLE); 1116 #ifdef CONFIG_XIP_KERNEL 1117 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1118 kernel_map.xiprom, PMD_SIZE, PAGE_KERNEL_EXEC); 1119 #else 1120 create_pmd_mapping(trampoline_pmd, kernel_map.virt_addr, 1121 kernel_map.phys_addr, PMD_SIZE, PAGE_KERNEL_EXEC); 1122 #endif 1123 #else 1124 /* Setup trampoline PGD */ 1125 create_pgd_mapping(trampoline_pg_dir, kernel_map.virt_addr, 1126 kernel_map.phys_addr, PGDIR_SIZE, PAGE_KERNEL_EXEC); 1127 #endif 1128 1129 /* 1130 * Setup early PGD covering entire kernel which will allow 1131 * us to reach paging_init(). We map all memory banks later 1132 * in setup_vm_final() below. 1133 */ 1134 create_kernel_page_table(early_pg_dir, true); 1135 1136 /* Setup early mapping for FDT early scan */ 1137 create_fdt_early_page_table(__fix_to_virt(FIX_FDT), dtb_pa); 1138 1139 /* 1140 * Bootime fixmap only can handle PMD_SIZE mapping. Thus, boot-ioremap 1141 * range can not span multiple pmds. 1142 */ 1143 BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 1144 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 1145 1146 #ifndef __PAGETABLE_PMD_FOLDED 1147 /* 1148 * Early ioremap fixmap is already created as it lies within first 2MB 1149 * of fixmap region. We always map PMD_SIZE. Thus, both FIX_BTMAP_END 1150 * FIX_BTMAP_BEGIN should lie in the same pmd. Verify that and warn 1151 * the user if not. 1152 */ 1153 fix_bmap_spmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_BEGIN))]; 1154 fix_bmap_epmd = fixmap_pmd[pmd_index(__fix_to_virt(FIX_BTMAP_END))]; 1155 if (pmd_val(fix_bmap_spmd) != pmd_val(fix_bmap_epmd)) { 1156 WARN_ON(1); 1157 pr_warn("fixmap btmap start [%08lx] != end [%08lx]\n", 1158 pmd_val(fix_bmap_spmd), pmd_val(fix_bmap_epmd)); 1159 pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 1160 fix_to_virt(FIX_BTMAP_BEGIN)); 1161 pr_warn("fix_to_virt(FIX_BTMAP_END): %08lx\n", 1162 fix_to_virt(FIX_BTMAP_END)); 1163 1164 pr_warn("FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 1165 pr_warn("FIX_BTMAP_BEGIN: %d\n", FIX_BTMAP_BEGIN); 1166 } 1167 #endif 1168 1169 pt_ops_set_fixmap(); 1170 } 1171 1172 static void __init create_linear_mapping_range(phys_addr_t start, 1173 phys_addr_t end, 1174 uintptr_t fixed_map_size) 1175 { 1176 phys_addr_t pa; 1177 uintptr_t va, map_size; 1178 1179 for (pa = start; pa < end; pa += map_size) { 1180 va = (uintptr_t)__va(pa); 1181 map_size = fixed_map_size ? fixed_map_size : 1182 best_map_size(pa, va, end - pa); 1183 1184 create_pgd_mapping(swapper_pg_dir, va, pa, map_size, 1185 pgprot_from_va(va)); 1186 } 1187 } 1188 1189 static void __init create_linear_mapping_page_table(void) 1190 { 1191 phys_addr_t start, end; 1192 phys_addr_t kfence_pool __maybe_unused; 1193 u64 i; 1194 1195 #ifdef CONFIG_STRICT_KERNEL_RWX 1196 phys_addr_t ktext_start = __pa_symbol(_start); 1197 phys_addr_t ktext_size = __init_data_begin - _start; 1198 phys_addr_t krodata_start = __pa_symbol(__start_rodata); 1199 phys_addr_t krodata_size = _data - __start_rodata; 1200 1201 /* Isolate kernel text and rodata so they don't get mapped with a PUD */ 1202 memblock_mark_nomap(ktext_start, ktext_size); 1203 memblock_mark_nomap(krodata_start, krodata_size); 1204 #endif 1205 1206 #ifdef CONFIG_KFENCE 1207 /* 1208 * kfence pool must be backed by PAGE_SIZE mappings, so allocate it 1209 * before we setup the linear mapping so that we avoid using hugepages 1210 * for this region. 1211 */ 1212 kfence_pool = memblock_phys_alloc(KFENCE_POOL_SIZE, PAGE_SIZE); 1213 BUG_ON(!kfence_pool); 1214 1215 memblock_mark_nomap(kfence_pool, KFENCE_POOL_SIZE); 1216 __kfence_pool = __va(kfence_pool); 1217 #endif 1218 1219 /* Map all memory banks in the linear mapping */ 1220 for_each_mem_range(i, &start, &end) { 1221 if (start >= end) 1222 break; 1223 if (start <= __pa(PAGE_OFFSET) && 1224 __pa(PAGE_OFFSET) < end) 1225 start = __pa(PAGE_OFFSET); 1226 if (end >= __pa(PAGE_OFFSET) + memory_limit) 1227 end = __pa(PAGE_OFFSET) + memory_limit; 1228 1229 create_linear_mapping_range(start, end, 0); 1230 } 1231 1232 #ifdef CONFIG_STRICT_KERNEL_RWX 1233 create_linear_mapping_range(ktext_start, ktext_start + ktext_size, 0); 1234 create_linear_mapping_range(krodata_start, 1235 krodata_start + krodata_size, 0); 1236 1237 memblock_clear_nomap(ktext_start, ktext_size); 1238 memblock_clear_nomap(krodata_start, krodata_size); 1239 #endif 1240 1241 #ifdef CONFIG_KFENCE 1242 create_linear_mapping_range(kfence_pool, 1243 kfence_pool + KFENCE_POOL_SIZE, 1244 PAGE_SIZE); 1245 1246 memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE); 1247 #endif 1248 } 1249 1250 static void __init setup_vm_final(void) 1251 { 1252 /* Setup swapper PGD for fixmap */ 1253 #if !defined(CONFIG_64BIT) 1254 /* 1255 * In 32-bit, the device tree lies in a pgd entry, so it must be copied 1256 * directly in swapper_pg_dir in addition to the pgd entry that points 1257 * to fixmap_pte. 1258 */ 1259 unsigned long idx = pgd_index(__fix_to_virt(FIX_FDT)); 1260 1261 set_pgd(&swapper_pg_dir[idx], early_pg_dir[idx]); 1262 #endif 1263 create_pgd_mapping(swapper_pg_dir, FIXADDR_START, 1264 __pa_symbol(fixmap_pgd_next), 1265 PGDIR_SIZE, PAGE_TABLE); 1266 1267 /* Map the linear mapping */ 1268 create_linear_mapping_page_table(); 1269 1270 /* Map the kernel */ 1271 if (IS_ENABLED(CONFIG_64BIT)) 1272 create_kernel_page_table(swapper_pg_dir, false); 1273 1274 #ifdef CONFIG_KASAN 1275 kasan_swapper_init(); 1276 #endif 1277 1278 /* Clear fixmap PTE and PMD mappings */ 1279 clear_fixmap(FIX_PTE); 1280 clear_fixmap(FIX_PMD); 1281 clear_fixmap(FIX_PUD); 1282 clear_fixmap(FIX_P4D); 1283 1284 /* Move to swapper page table */ 1285 csr_write(CSR_SATP, PFN_DOWN(__pa_symbol(swapper_pg_dir)) | satp_mode); 1286 local_flush_tlb_all(); 1287 1288 pt_ops_set_late(); 1289 } 1290 #else 1291 asmlinkage void __init setup_vm(uintptr_t dtb_pa) 1292 { 1293 dtb_early_va = (void *)dtb_pa; 1294 dtb_early_pa = dtb_pa; 1295 } 1296 1297 static inline void setup_vm_final(void) 1298 { 1299 } 1300 #endif /* CONFIG_MMU */ 1301 1302 /* 1303 * reserve_crashkernel() - reserves memory for crash kernel 1304 * 1305 * This function reserves memory area given in "crashkernel=" kernel command 1306 * line parameter. The memory reserved is used by dump capture kernel when 1307 * primary kernel is crashing. 1308 */ 1309 static void __init reserve_crashkernel(void) 1310 { 1311 unsigned long long crash_base = 0; 1312 unsigned long long crash_size = 0; 1313 unsigned long search_start = memblock_start_of_DRAM(); 1314 unsigned long search_end = memblock_end_of_DRAM(); 1315 1316 int ret = 0; 1317 1318 if (!IS_ENABLED(CONFIG_KEXEC_CORE)) 1319 return; 1320 /* 1321 * Don't reserve a region for a crash kernel on a crash kernel 1322 * since it doesn't make much sense and we have limited memory 1323 * resources. 1324 */ 1325 if (is_kdump_kernel()) { 1326 pr_info("crashkernel: ignoring reservation request\n"); 1327 return; 1328 } 1329 1330 ret = parse_crashkernel(boot_command_line, memblock_phys_mem_size(), 1331 &crash_size, &crash_base); 1332 if (ret || !crash_size) 1333 return; 1334 1335 crash_size = PAGE_ALIGN(crash_size); 1336 1337 if (crash_base) { 1338 search_start = crash_base; 1339 search_end = crash_base + crash_size; 1340 } 1341 1342 /* 1343 * Current riscv boot protocol requires 2MB alignment for 1344 * RV64 and 4MB alignment for RV32 (hugepage size) 1345 * 1346 * Try to alloc from 32bit addressible physical memory so that 1347 * swiotlb can work on the crash kernel. 1348 */ 1349 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1350 search_start, 1351 min(search_end, (unsigned long)(SZ_4G - 1))); 1352 if (crash_base == 0) { 1353 /* Try again without restricting region to 32bit addressible memory */ 1354 crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE, 1355 search_start, search_end); 1356 if (crash_base == 0) { 1357 pr_warn("crashkernel: couldn't allocate %lldKB\n", 1358 crash_size >> 10); 1359 return; 1360 } 1361 } 1362 1363 pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n", 1364 crash_base, crash_base + crash_size, crash_size >> 20); 1365 1366 crashk_res.start = crash_base; 1367 crashk_res.end = crash_base + crash_size - 1; 1368 } 1369 1370 void __init paging_init(void) 1371 { 1372 setup_bootmem(); 1373 setup_vm_final(); 1374 1375 /* Depend on that Linear Mapping is ready */ 1376 memblock_allow_resize(); 1377 } 1378 1379 void __init misc_mem_init(void) 1380 { 1381 early_memtest(min_low_pfn << PAGE_SHIFT, max_low_pfn << PAGE_SHIFT); 1382 arch_numa_init(); 1383 sparse_init(); 1384 zone_sizes_init(); 1385 reserve_crashkernel(); 1386 memblock_dump_all(); 1387 } 1388 1389 #ifdef CONFIG_SPARSEMEM_VMEMMAP 1390 int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node, 1391 struct vmem_altmap *altmap) 1392 { 1393 return vmemmap_populate_basepages(start, end, node, NULL); 1394 } 1395 #endif 1396 1397 #if defined(CONFIG_MMU) && defined(CONFIG_64BIT) 1398 /* 1399 * Pre-allocates page-table pages for a specific area in the kernel 1400 * page-table. Only the level which needs to be synchronized between 1401 * all page-tables is allocated because the synchronization can be 1402 * expensive. 1403 */ 1404 static void __init preallocate_pgd_pages_range(unsigned long start, unsigned long end, 1405 const char *area) 1406 { 1407 unsigned long addr; 1408 const char *lvl; 1409 1410 for (addr = start; addr < end && addr >= start; addr = ALIGN(addr + 1, PGDIR_SIZE)) { 1411 pgd_t *pgd = pgd_offset_k(addr); 1412 p4d_t *p4d; 1413 pud_t *pud; 1414 pmd_t *pmd; 1415 1416 lvl = "p4d"; 1417 p4d = p4d_alloc(&init_mm, pgd, addr); 1418 if (!p4d) 1419 goto failed; 1420 1421 if (pgtable_l5_enabled) 1422 continue; 1423 1424 lvl = "pud"; 1425 pud = pud_alloc(&init_mm, p4d, addr); 1426 if (!pud) 1427 goto failed; 1428 1429 if (pgtable_l4_enabled) 1430 continue; 1431 1432 lvl = "pmd"; 1433 pmd = pmd_alloc(&init_mm, pud, addr); 1434 if (!pmd) 1435 goto failed; 1436 } 1437 return; 1438 1439 failed: 1440 /* 1441 * The pages have to be there now or they will be missing in 1442 * process page-tables later. 1443 */ 1444 panic("Failed to pre-allocate %s pages for %s area\n", lvl, area); 1445 } 1446 1447 void __init pgtable_cache_init(void) 1448 { 1449 preallocate_pgd_pages_range(VMALLOC_START, VMALLOC_END, "vmalloc"); 1450 if (IS_ENABLED(CONFIG_MODULES)) 1451 preallocate_pgd_pages_range(MODULES_VADDR, MODULES_END, "bpf/modules"); 1452 } 1453 #endif 1454