1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * Re-map IO memory to kernel address space so that we can access it. 4 * This is needed for high PCI addresses that aren't mapped in the 5 * 640k-1MB IO memory area on PC's 6 * 7 * (C) Copyright 1995 1996 Linus Torvalds 8 */ 9 10#include <linux/memblock.h> 11#include <linux/init.h> 12#include <linux/io.h> 13#include <linux/ioport.h> 14#include <linux/slab.h> 15#include <linux/vmalloc.h> 16#include <linux/mmiotrace.h> 17#include <linux/cc_platform.h> 18#include <linux/efi.h> 19#include <linux/pgtable.h> 20#include <linux/kmsan.h> 21 22#include <asm/set_memory.h> 23#include <asm/e820/api.h> 24#include <asm/efi.h> 25#include <asm/fixmap.h> 26#include <asm/tlbflush.h> 27#include <asm/pgalloc.h> 28#include <asm/memtype.h> 29#include <asm/setup.h> 30 31#include "physaddr.h" 32 33/* 34 * Descriptor controlling ioremap() behavior. 35 */ 36struct ioremap_desc { 37 unsigned int flags; 38}; 39 40/* 41 * Fix up the linear direct mapping of the kernel to avoid cache attribute 42 * conflicts. 43 */ 44int ioremap_change_attr(unsigned long vaddr, unsigned long size, 45 enum page_cache_mode pcm) 46{ 47 unsigned long nrpages = size >> PAGE_SHIFT; 48 int err; 49 50 switch (pcm) { 51 case _PAGE_CACHE_MODE_UC: 52 default: 53 err = _set_memory_uc(vaddr, nrpages); 54 break; 55 case _PAGE_CACHE_MODE_WC: 56 err = _set_memory_wc(vaddr, nrpages); 57 break; 58 case _PAGE_CACHE_MODE_WT: 59 err = _set_memory_wt(vaddr, nrpages); 60 break; 61 case _PAGE_CACHE_MODE_WB: 62 err = _set_memory_wb(vaddr, nrpages); 63 break; 64 } 65 66 return err; 67} 68 69/* Does the range (or a subset of) contain normal RAM? */ 70static unsigned int __ioremap_check_ram(struct resource *res) 71{ 72 unsigned long start_pfn, stop_pfn; 73 unsigned long i; 74 75 if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM) 76 return 0; 77 78 start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT; 79 stop_pfn = (res->end + 1) >> PAGE_SHIFT; 80 if (stop_pfn > start_pfn) { 81 for (i = 0; i < (stop_pfn - start_pfn); ++i) 82 if (pfn_valid(start_pfn + i) && 83 !PageReserved(pfn_to_page(start_pfn + i))) 84 return IORES_MAP_SYSTEM_RAM; 85 } 86 87 return 0; 88} 89 90/* 91 * In a SEV guest, NONE and RESERVED should not be mapped encrypted because 92 * there the whole memory is already encrypted. 93 */ 94static unsigned int __ioremap_check_encrypted(struct resource *res) 95{ 96 if (!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) 97 return 0; 98 99 switch (res->desc) { 100 case IORES_DESC_NONE: 101 case IORES_DESC_RESERVED: 102 break; 103 default: 104 return IORES_MAP_ENCRYPTED; 105 } 106 107 return 0; 108} 109 110/* 111 * The EFI runtime services data area is not covered by walk_mem_res(), but must 112 * be mapped encrypted when SEV is active. 113 */ 114static void __ioremap_check_other(resource_size_t addr, struct ioremap_desc *desc) 115{ 116 if (!cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) 117 return; 118 119 if (x86_platform.hyper.is_private_mmio(addr)) { 120 desc->flags |= IORES_MAP_ENCRYPTED; 121 return; 122 } 123 124 if (!IS_ENABLED(CONFIG_EFI)) 125 return; 126 127 if (efi_mem_type(addr) == EFI_RUNTIME_SERVICES_DATA || 128 (efi_mem_type(addr) == EFI_BOOT_SERVICES_DATA && 129 efi_mem_attributes(addr) & EFI_MEMORY_RUNTIME)) 130 desc->flags |= IORES_MAP_ENCRYPTED; 131} 132 133static int __ioremap_collect_map_flags(struct resource *res, void *arg) 134{ 135 struct ioremap_desc *desc = arg; 136 137 if (!(desc->flags & IORES_MAP_SYSTEM_RAM)) 138 desc->flags |= __ioremap_check_ram(res); 139 140 if (!(desc->flags & IORES_MAP_ENCRYPTED)) 141 desc->flags |= __ioremap_check_encrypted(res); 142 143 return ((desc->flags & (IORES_MAP_SYSTEM_RAM | IORES_MAP_ENCRYPTED)) == 144 (IORES_MAP_SYSTEM_RAM | IORES_MAP_ENCRYPTED)); 145} 146 147/* 148 * To avoid multiple resource walks, this function walks resources marked as 149 * IORESOURCE_MEM and IORESOURCE_BUSY and looking for system RAM and/or a 150 * resource described not as IORES_DESC_NONE (e.g. IORES_DESC_ACPI_TABLES). 151 * 152 * After that, deal with misc other ranges in __ioremap_check_other() which do 153 * not fall into the above category. 154 */ 155static void __ioremap_check_mem(resource_size_t addr, unsigned long size, 156 struct ioremap_desc *desc) 157{ 158 u64 start, end; 159 160 start = (u64)addr; 161 end = start + size - 1; 162 memset(desc, 0, sizeof(struct ioremap_desc)); 163 164 walk_mem_res(start, end, desc, __ioremap_collect_map_flags); 165 166 __ioremap_check_other(addr, desc); 167} 168 169/* 170 * Remap an arbitrary physical address space into the kernel virtual 171 * address space. It transparently creates kernel huge I/O mapping when 172 * the physical address is aligned by a huge page size (1GB or 2MB) and 173 * the requested size is at least the huge page size. 174 * 175 * NOTE: MTRRs can override PAT memory types with a 4KB granularity. 176 * Therefore, the mapping code falls back to use a smaller page toward 4KB 177 * when a mapping range is covered by non-WB type of MTRRs. 178 * 179 * NOTE! We need to allow non-page-aligned mappings too: we will obviously 180 * have to convert them into an offset in a page-aligned mapping, but the 181 * caller shouldn't need to know that small detail. 182 */ 183static void __iomem * 184__ioremap_caller(resource_size_t phys_addr, unsigned long size, 185 enum page_cache_mode pcm, void *caller, bool encrypted) 186{ 187 unsigned long offset, vaddr; 188 resource_size_t last_addr; 189 const resource_size_t unaligned_phys_addr = phys_addr; 190 const unsigned long unaligned_size = size; 191 struct ioremap_desc io_desc; 192 struct vm_struct *area; 193 enum page_cache_mode new_pcm; 194 pgprot_t prot; 195 int retval; 196 void __iomem *ret_addr; 197 198 /* Don't allow wraparound or zero size */ 199 last_addr = phys_addr + size - 1; 200 if (!size || last_addr < phys_addr) 201 return NULL; 202 203 if (!phys_addr_valid(phys_addr)) { 204 printk(KERN_WARNING "ioremap: invalid physical address %llx\n", 205 (unsigned long long)phys_addr); 206 WARN_ON_ONCE(1); 207 return NULL; 208 } 209 210 __ioremap_check_mem(phys_addr, size, &io_desc); 211 212 /* 213 * Don't allow anybody to remap normal RAM that we're using.. 214 */ 215 if (io_desc.flags & IORES_MAP_SYSTEM_RAM) { 216 WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n", 217 &phys_addr, &last_addr); 218 return NULL; 219 } 220 221 /* 222 * Mappings have to be page-aligned 223 */ 224 offset = phys_addr & ~PAGE_MASK; 225 phys_addr &= PAGE_MASK; 226 size = PAGE_ALIGN(last_addr+1) - phys_addr; 227 228 /* 229 * Mask out any bits not part of the actual physical 230 * address, like memory encryption bits. 231 */ 232 phys_addr &= PHYSICAL_PAGE_MASK; 233 234 retval = memtype_reserve(phys_addr, (u64)phys_addr + size, 235 pcm, &new_pcm); 236 if (retval) { 237 printk(KERN_ERR "ioremap memtype_reserve failed %d\n", retval); 238 return NULL; 239 } 240 241 if (pcm != new_pcm) { 242 if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) { 243 printk(KERN_ERR 244 "ioremap error for 0x%llx-0x%llx, requested 0x%x, got 0x%x\n", 245 (unsigned long long)phys_addr, 246 (unsigned long long)(phys_addr + size), 247 pcm, new_pcm); 248 goto err_free_memtype; 249 } 250 pcm = new_pcm; 251 } 252 253 /* 254 * If the page being mapped is in memory and SEV is active then 255 * make sure the memory encryption attribute is enabled in the 256 * resulting mapping. 257 * In TDX guests, memory is marked private by default. If encryption 258 * is not requested (using encrypted), explicitly set decrypt 259 * attribute in all IOREMAPPED memory. 260 */ 261 prot = PAGE_KERNEL_IO; 262 if ((io_desc.flags & IORES_MAP_ENCRYPTED) || encrypted) 263 prot = pgprot_encrypted(prot); 264 else 265 prot = pgprot_decrypted(prot); 266 267 switch (pcm) { 268 case _PAGE_CACHE_MODE_UC: 269 default: 270 prot = __pgprot(pgprot_val(prot) | 271 cachemode2protval(_PAGE_CACHE_MODE_UC)); 272 break; 273 case _PAGE_CACHE_MODE_UC_MINUS: 274 prot = __pgprot(pgprot_val(prot) | 275 cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS)); 276 break; 277 case _PAGE_CACHE_MODE_WC: 278 prot = __pgprot(pgprot_val(prot) | 279 cachemode2protval(_PAGE_CACHE_MODE_WC)); 280 break; 281 case _PAGE_CACHE_MODE_WT: 282 prot = __pgprot(pgprot_val(prot) | 283 cachemode2protval(_PAGE_CACHE_MODE_WT)); 284 break; 285 case _PAGE_CACHE_MODE_WB: 286 break; 287 } 288 289 /* 290 * Ok, go for it.. 291 */ 292 area = get_vm_area_caller(size, VM_IOREMAP, caller); 293 if (!area) 294 goto err_free_memtype; 295 area->phys_addr = phys_addr; 296 vaddr = (unsigned long) area->addr; 297 298 if (memtype_kernel_map_sync(phys_addr, size, pcm)) 299 goto err_free_area; 300 301 if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) 302 goto err_free_area; 303 304 ret_addr = (void __iomem *) (vaddr + offset); 305 mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr); 306 307 /* 308 * Check if the request spans more than any BAR in the iomem resource 309 * tree. 310 */ 311 if (iomem_map_sanity_check(unaligned_phys_addr, unaligned_size)) 312 pr_warn("caller %pS mapping multiple BARs\n", caller); 313 314 return ret_addr; 315err_free_area: 316 free_vm_area(area); 317err_free_memtype: 318 memtype_free(phys_addr, phys_addr + size); 319 return NULL; 320} 321 322/** 323 * ioremap - map bus memory into CPU space 324 * @phys_addr: bus address of the memory 325 * @size: size of the resource to map 326 * 327 * ioremap performs a platform specific sequence of operations to 328 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 329 * writew/writel functions and the other mmio helpers. The returned 330 * address is not guaranteed to be usable directly as a virtual 331 * address. 332 * 333 * This version of ioremap ensures that the memory is marked uncachable 334 * on the CPU as well as honouring existing caching rules from things like 335 * the PCI bus. Note that there are other caches and buffers on many 336 * busses. In particular driver authors should read up on PCI writes 337 * 338 * It's useful if some control registers are in such an area and 339 * write combining or read caching is not desirable: 340 * 341 * Must be freed with iounmap. 342 */ 343void __iomem *ioremap(resource_size_t phys_addr, unsigned long size) 344{ 345 /* 346 * Ideally, this should be: 347 * pat_enabled() ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS; 348 * 349 * Till we fix all X drivers to use ioremap_wc(), we will use 350 * UC MINUS. Drivers that are certain they need or can already 351 * be converted over to strong UC can use ioremap_uc(). 352 */ 353 enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS; 354 355 return __ioremap_caller(phys_addr, size, pcm, 356 __builtin_return_address(0), false); 357} 358EXPORT_SYMBOL(ioremap); 359 360/** 361 * ioremap_uc - map bus memory into CPU space as strongly uncachable 362 * @phys_addr: bus address of the memory 363 * @size: size of the resource to map 364 * 365 * ioremap_uc performs a platform specific sequence of operations to 366 * make bus memory CPU accessible via the readb/readw/readl/writeb/ 367 * writew/writel functions and the other mmio helpers. The returned 368 * address is not guaranteed to be usable directly as a virtual 369 * address. 370 * 371 * This version of ioremap ensures that the memory is marked with a strong 372 * preference as completely uncachable on the CPU when possible. For non-PAT 373 * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT 374 * systems this will set the PAT entry for the pages as strong UC. This call 375 * will honor existing caching rules from things like the PCI bus. Note that 376 * there are other caches and buffers on many busses. In particular driver 377 * authors should read up on PCI writes. 378 * 379 * It's useful if some control registers are in such an area and 380 * write combining or read caching is not desirable: 381 * 382 * Must be freed with iounmap. 383 */ 384void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size) 385{ 386 enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC; 387 388 return __ioremap_caller(phys_addr, size, pcm, 389 __builtin_return_address(0), false); 390} 391EXPORT_SYMBOL_GPL(ioremap_uc); 392 393/** 394 * ioremap_wc - map memory into CPU space write combined 395 * @phys_addr: bus address of the memory 396 * @size: size of the resource to map 397 * 398 * This version of ioremap ensures that the memory is marked write combining. 399 * Write combining allows faster writes to some hardware devices. 400 * 401 * Must be freed with iounmap. 402 */ 403void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size) 404{ 405 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC, 406 __builtin_return_address(0), false); 407} 408EXPORT_SYMBOL(ioremap_wc); 409 410/** 411 * ioremap_wt - map memory into CPU space write through 412 * @phys_addr: bus address of the memory 413 * @size: size of the resource to map 414 * 415 * This version of ioremap ensures that the memory is marked write through. 416 * Write through stores data into memory while keeping the cache up-to-date. 417 * 418 * Must be freed with iounmap. 419 */ 420void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size) 421{ 422 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT, 423 __builtin_return_address(0), false); 424} 425EXPORT_SYMBOL(ioremap_wt); 426 427void __iomem *ioremap_encrypted(resource_size_t phys_addr, unsigned long size) 428{ 429 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB, 430 __builtin_return_address(0), true); 431} 432EXPORT_SYMBOL(ioremap_encrypted); 433 434void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size) 435{ 436 return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB, 437 __builtin_return_address(0), false); 438} 439EXPORT_SYMBOL(ioremap_cache); 440 441void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size, 442 unsigned long prot_val) 443{ 444 return __ioremap_caller(phys_addr, size, 445 pgprot2cachemode(__pgprot(prot_val)), 446 __builtin_return_address(0), false); 447} 448EXPORT_SYMBOL(ioremap_prot); 449 450/** 451 * iounmap - Free a IO remapping 452 * @addr: virtual address from ioremap_* 453 * 454 * Caller must ensure there is only one unmapping for the same pointer. 455 */ 456void iounmap(volatile void __iomem *addr) 457{ 458 struct vm_struct *p, *o; 459 460 if ((void __force *)addr <= high_memory) 461 return; 462 463 /* 464 * The PCI/ISA range special-casing was removed from __ioremap() 465 * so this check, in theory, can be removed. However, there are 466 * cases where iounmap() is called for addresses not obtained via 467 * ioremap() (vga16fb for example). Add a warning so that these 468 * cases can be caught and fixed. 469 */ 470 if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) && 471 (void __force *)addr < phys_to_virt(ISA_END_ADDRESS)) { 472 WARN(1, "iounmap() called for ISA range not obtained using ioremap()\n"); 473 return; 474 } 475 476 mmiotrace_iounmap(addr); 477 478 addr = (volatile void __iomem *) 479 (PAGE_MASK & (unsigned long __force)addr); 480 481 /* Use the vm area unlocked, assuming the caller 482 ensures there isn't another iounmap for the same address 483 in parallel. Reuse of the virtual address is prevented by 484 leaving it in the global lists until we're done with it. 485 cpa takes care of the direct mappings. */ 486 p = find_vm_area((void __force *)addr); 487 488 if (!p) { 489 printk(KERN_ERR "iounmap: bad address %p\n", addr); 490 dump_stack(); 491 return; 492 } 493 494 kmsan_iounmap_page_range((unsigned long)addr, 495 (unsigned long)addr + get_vm_area_size(p)); 496 memtype_free(p->phys_addr, p->phys_addr + get_vm_area_size(p)); 497 498 /* Finally remove it */ 499 o = remove_vm_area((void __force *)addr); 500 BUG_ON(p != o || o == NULL); 501 kfree(p); 502} 503EXPORT_SYMBOL(iounmap); 504 505/* 506 * Convert a physical pointer to a virtual kernel pointer for /dev/mem 507 * access 508 */ 509void *xlate_dev_mem_ptr(phys_addr_t phys) 510{ 511 unsigned long start = phys & PAGE_MASK; 512 unsigned long offset = phys & ~PAGE_MASK; 513 void *vaddr; 514 515 /* memremap() maps if RAM, otherwise falls back to ioremap() */ 516 vaddr = memremap(start, PAGE_SIZE, MEMREMAP_WB); 517 518 /* Only add the offset on success and return NULL if memremap() failed */ 519 if (vaddr) 520 vaddr += offset; 521 522 return vaddr; 523} 524 525void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr) 526{ 527 memunmap((void *)((unsigned long)addr & PAGE_MASK)); 528} 529 530#ifdef CONFIG_AMD_MEM_ENCRYPT 531/* 532 * Examine the physical address to determine if it is an area of memory 533 * that should be mapped decrypted. If the memory is not part of the 534 * kernel usable area it was accessed and created decrypted, so these 535 * areas should be mapped decrypted. And since the encryption key can 536 * change across reboots, persistent memory should also be mapped 537 * decrypted. 538 * 539 * If SEV is active, that implies that BIOS/UEFI also ran encrypted so 540 * only persistent memory should be mapped decrypted. 541 */ 542static bool memremap_should_map_decrypted(resource_size_t phys_addr, 543 unsigned long size) 544{ 545 int is_pmem; 546 547 /* 548 * Check if the address is part of a persistent memory region. 549 * This check covers areas added by E820, EFI and ACPI. 550 */ 551 is_pmem = region_intersects(phys_addr, size, IORESOURCE_MEM, 552 IORES_DESC_PERSISTENT_MEMORY); 553 if (is_pmem != REGION_DISJOINT) 554 return true; 555 556 /* 557 * Check if the non-volatile attribute is set for an EFI 558 * reserved area. 559 */ 560 if (efi_enabled(EFI_BOOT)) { 561 switch (efi_mem_type(phys_addr)) { 562 case EFI_RESERVED_TYPE: 563 if (efi_mem_attributes(phys_addr) & EFI_MEMORY_NV) 564 return true; 565 break; 566 default: 567 break; 568 } 569 } 570 571 /* Check if the address is outside kernel usable area */ 572 switch (e820__get_entry_type(phys_addr, phys_addr + size - 1)) { 573 case E820_TYPE_RESERVED: 574 case E820_TYPE_ACPI: 575 case E820_TYPE_NVS: 576 case E820_TYPE_UNUSABLE: 577 /* For SEV, these areas are encrypted */ 578 if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) 579 break; 580 fallthrough; 581 582 case E820_TYPE_PRAM: 583 return true; 584 default: 585 break; 586 } 587 588 return false; 589} 590 591/* 592 * Examine the physical address to determine if it is EFI data. Check 593 * it against the boot params structure and EFI tables and memory types. 594 */ 595static bool memremap_is_efi_data(resource_size_t phys_addr, 596 unsigned long size) 597{ 598 u64 paddr; 599 600 /* Check if the address is part of EFI boot/runtime data */ 601 if (!efi_enabled(EFI_BOOT)) 602 return false; 603 604 paddr = boot_params.efi_info.efi_memmap_hi; 605 paddr <<= 32; 606 paddr |= boot_params.efi_info.efi_memmap; 607 if (phys_addr == paddr) 608 return true; 609 610 paddr = boot_params.efi_info.efi_systab_hi; 611 paddr <<= 32; 612 paddr |= boot_params.efi_info.efi_systab; 613 if (phys_addr == paddr) 614 return true; 615 616 if (efi_is_table_address(phys_addr)) 617 return true; 618 619 switch (efi_mem_type(phys_addr)) { 620 case EFI_BOOT_SERVICES_DATA: 621 case EFI_RUNTIME_SERVICES_DATA: 622 return true; 623 default: 624 break; 625 } 626 627 return false; 628} 629 630/* 631 * Examine the physical address to determine if it is boot data by checking 632 * it against the boot params setup_data chain. 633 */ 634static bool memremap_is_setup_data(resource_size_t phys_addr, 635 unsigned long size) 636{ 637 struct setup_indirect *indirect; 638 struct setup_data *data; 639 u64 paddr, paddr_next; 640 641 paddr = boot_params.hdr.setup_data; 642 while (paddr) { 643 unsigned int len; 644 645 if (phys_addr == paddr) 646 return true; 647 648 data = memremap(paddr, sizeof(*data), 649 MEMREMAP_WB | MEMREMAP_DEC); 650 if (!data) { 651 pr_warn("failed to memremap setup_data entry\n"); 652 return false; 653 } 654 655 paddr_next = data->next; 656 len = data->len; 657 658 if ((phys_addr > paddr) && (phys_addr < (paddr + len))) { 659 memunmap(data); 660 return true; 661 } 662 663 if (data->type == SETUP_INDIRECT) { 664 memunmap(data); 665 data = memremap(paddr, sizeof(*data) + len, 666 MEMREMAP_WB | MEMREMAP_DEC); 667 if (!data) { 668 pr_warn("failed to memremap indirect setup_data\n"); 669 return false; 670 } 671 672 indirect = (struct setup_indirect *)data->data; 673 674 if (indirect->type != SETUP_INDIRECT) { 675 paddr = indirect->addr; 676 len = indirect->len; 677 } 678 } 679 680 memunmap(data); 681 682 if ((phys_addr > paddr) && (phys_addr < (paddr + len))) 683 return true; 684 685 paddr = paddr_next; 686 } 687 688 return false; 689} 690 691/* 692 * Examine the physical address to determine if it is boot data by checking 693 * it against the boot params setup_data chain (early boot version). 694 */ 695static bool __init early_memremap_is_setup_data(resource_size_t phys_addr, 696 unsigned long size) 697{ 698 struct setup_indirect *indirect; 699 struct setup_data *data; 700 u64 paddr, paddr_next; 701 702 paddr = boot_params.hdr.setup_data; 703 while (paddr) { 704 unsigned int len, size; 705 706 if (phys_addr == paddr) 707 return true; 708 709 data = early_memremap_decrypted(paddr, sizeof(*data)); 710 if (!data) { 711 pr_warn("failed to early memremap setup_data entry\n"); 712 return false; 713 } 714 715 size = sizeof(*data); 716 717 paddr_next = data->next; 718 len = data->len; 719 720 if ((phys_addr > paddr) && (phys_addr < (paddr + len))) { 721 early_memunmap(data, sizeof(*data)); 722 return true; 723 } 724 725 if (data->type == SETUP_INDIRECT) { 726 size += len; 727 early_memunmap(data, sizeof(*data)); 728 data = early_memremap_decrypted(paddr, size); 729 if (!data) { 730 pr_warn("failed to early memremap indirect setup_data\n"); 731 return false; 732 } 733 734 indirect = (struct setup_indirect *)data->data; 735 736 if (indirect->type != SETUP_INDIRECT) { 737 paddr = indirect->addr; 738 len = indirect->len; 739 } 740 } 741 742 early_memunmap(data, size); 743 744 if ((phys_addr > paddr) && (phys_addr < (paddr + len))) 745 return true; 746 747 paddr = paddr_next; 748 } 749 750 return false; 751} 752 753/* 754 * Architecture function to determine if RAM remap is allowed. By default, a 755 * RAM remap will map the data as encrypted. Determine if a RAM remap should 756 * not be done so that the data will be mapped decrypted. 757 */ 758bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size, 759 unsigned long flags) 760{ 761 if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) 762 return true; 763 764 if (flags & MEMREMAP_ENC) 765 return true; 766 767 if (flags & MEMREMAP_DEC) 768 return false; 769 770 if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) { 771 if (memremap_is_setup_data(phys_addr, size) || 772 memremap_is_efi_data(phys_addr, size)) 773 return false; 774 } 775 776 return !memremap_should_map_decrypted(phys_addr, size); 777} 778 779/* 780 * Architecture override of __weak function to adjust the protection attributes 781 * used when remapping memory. By default, early_memremap() will map the data 782 * as encrypted. Determine if an encrypted mapping should not be done and set 783 * the appropriate protection attributes. 784 */ 785pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr, 786 unsigned long size, 787 pgprot_t prot) 788{ 789 bool encrypted_prot; 790 791 if (!cc_platform_has(CC_ATTR_MEM_ENCRYPT)) 792 return prot; 793 794 encrypted_prot = true; 795 796 if (cc_platform_has(CC_ATTR_HOST_MEM_ENCRYPT)) { 797 if (early_memremap_is_setup_data(phys_addr, size) || 798 memremap_is_efi_data(phys_addr, size)) 799 encrypted_prot = false; 800 } 801 802 if (encrypted_prot && memremap_should_map_decrypted(phys_addr, size)) 803 encrypted_prot = false; 804 805 return encrypted_prot ? pgprot_encrypted(prot) 806 : pgprot_decrypted(prot); 807} 808 809bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size) 810{ 811 return arch_memremap_can_ram_remap(phys_addr, size, 0); 812} 813 814/* Remap memory with encryption */ 815void __init *early_memremap_encrypted(resource_size_t phys_addr, 816 unsigned long size) 817{ 818 return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC); 819} 820 821/* 822 * Remap memory with encryption and write-protected - cannot be called 823 * before pat_init() is called 824 */ 825void __init *early_memremap_encrypted_wp(resource_size_t phys_addr, 826 unsigned long size) 827{ 828 if (!x86_has_pat_wp()) 829 return NULL; 830 return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC_WP); 831} 832 833/* Remap memory without encryption */ 834void __init *early_memremap_decrypted(resource_size_t phys_addr, 835 unsigned long size) 836{ 837 return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC); 838} 839 840/* 841 * Remap memory without encryption and write-protected - cannot be called 842 * before pat_init() is called 843 */ 844void __init *early_memremap_decrypted_wp(resource_size_t phys_addr, 845 unsigned long size) 846{ 847 if (!x86_has_pat_wp()) 848 return NULL; 849 return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP); 850} 851#endif /* CONFIG_AMD_MEM_ENCRYPT */ 852 853static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss; 854 855static inline pmd_t * __init early_ioremap_pmd(unsigned long addr) 856{ 857 /* Don't assume we're using swapper_pg_dir at this point */ 858 pgd_t *base = __va(read_cr3_pa()); 859 pgd_t *pgd = &base[pgd_index(addr)]; 860 p4d_t *p4d = p4d_offset(pgd, addr); 861 pud_t *pud = pud_offset(p4d, addr); 862 pmd_t *pmd = pmd_offset(pud, addr); 863 864 return pmd; 865} 866 867static inline pte_t * __init early_ioremap_pte(unsigned long addr) 868{ 869 return &bm_pte[pte_index(addr)]; 870} 871 872bool __init is_early_ioremap_ptep(pte_t *ptep) 873{ 874 return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)]; 875} 876 877void __init early_ioremap_init(void) 878{ 879 pmd_t *pmd; 880 881#ifdef CONFIG_X86_64 882 BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); 883#else 884 WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1)); 885#endif 886 887 early_ioremap_setup(); 888 889 pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)); 890 memset(bm_pte, 0, sizeof(bm_pte)); 891 pmd_populate_kernel(&init_mm, pmd, bm_pte); 892 893 /* 894 * The boot-ioremap range spans multiple pmds, for which 895 * we are not prepared: 896 */ 897#define __FIXADDR_TOP (-PAGE_SIZE) 898 BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT) 899 != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT)); 900#undef __FIXADDR_TOP 901 if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) { 902 WARN_ON(1); 903 printk(KERN_WARNING "pmd %p != %p\n", 904 pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))); 905 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n", 906 fix_to_virt(FIX_BTMAP_BEGIN)); 907 printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END): %08lx\n", 908 fix_to_virt(FIX_BTMAP_END)); 909 910 printk(KERN_WARNING "FIX_BTMAP_END: %d\n", FIX_BTMAP_END); 911 printk(KERN_WARNING "FIX_BTMAP_BEGIN: %d\n", 912 FIX_BTMAP_BEGIN); 913 } 914} 915 916void __init __early_set_fixmap(enum fixed_addresses idx, 917 phys_addr_t phys, pgprot_t flags) 918{ 919 unsigned long addr = __fix_to_virt(idx); 920 pte_t *pte; 921 922 if (idx >= __end_of_fixed_addresses) { 923 BUG(); 924 return; 925 } 926 pte = early_ioremap_pte(addr); 927 928 /* Sanitize 'prot' against any unsupported bits: */ 929 pgprot_val(flags) &= __supported_pte_mask; 930 931 if (pgprot_val(flags)) 932 set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags)); 933 else 934 pte_clear(&init_mm, addr, pte); 935 flush_tlb_one_kernel(addr); 936} 937