linux/arch/x86/mm/ioremap.c
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   1/*
   2 * Re-map IO memory to kernel address space so that we can access it.
   3 * This is needed for high PCI addresses that aren't mapped in the
   4 * 640k-1MB IO memory area on PC's
   5 *
   6 * (C) Copyright 1995 1996 Linus Torvalds
   7 */
   8
   9#include <linux/bootmem.h>
  10#include <linux/init.h>
  11#include <linux/io.h>
  12#include <linux/ioport.h>
  13#include <linux/slab.h>
  14#include <linux/vmalloc.h>
  15#include <linux/mmiotrace.h>
  16#include <linux/mem_encrypt.h>
  17#include <linux/efi.h>
  18
  19#include <asm/set_memory.h>
  20#include <asm/e820/api.h>
  21#include <asm/fixmap.h>
  22#include <asm/pgtable.h>
  23#include <asm/tlbflush.h>
  24#include <asm/pgalloc.h>
  25#include <asm/pat.h>
  26#include <asm/setup.h>
  27
  28#include "physaddr.h"
  29
  30struct ioremap_mem_flags {
  31        bool system_ram;
  32        bool desc_other;
  33};
  34
  35/*
  36 * Fix up the linear direct mapping of the kernel to avoid cache attribute
  37 * conflicts.
  38 */
  39int ioremap_change_attr(unsigned long vaddr, unsigned long size,
  40                        enum page_cache_mode pcm)
  41{
  42        unsigned long nrpages = size >> PAGE_SHIFT;
  43        int err;
  44
  45        switch (pcm) {
  46        case _PAGE_CACHE_MODE_UC:
  47        default:
  48                err = _set_memory_uc(vaddr, nrpages);
  49                break;
  50        case _PAGE_CACHE_MODE_WC:
  51                err = _set_memory_wc(vaddr, nrpages);
  52                break;
  53        case _PAGE_CACHE_MODE_WT:
  54                err = _set_memory_wt(vaddr, nrpages);
  55                break;
  56        case _PAGE_CACHE_MODE_WB:
  57                err = _set_memory_wb(vaddr, nrpages);
  58                break;
  59        }
  60
  61        return err;
  62}
  63
  64static bool __ioremap_check_ram(struct resource *res)
  65{
  66        unsigned long start_pfn, stop_pfn;
  67        unsigned long i;
  68
  69        if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM)
  70                return false;
  71
  72        start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT;
  73        stop_pfn = (res->end + 1) >> PAGE_SHIFT;
  74        if (stop_pfn > start_pfn) {
  75                for (i = 0; i < (stop_pfn - start_pfn); ++i)
  76                        if (pfn_valid(start_pfn + i) &&
  77                            !PageReserved(pfn_to_page(start_pfn + i)))
  78                                return true;
  79        }
  80
  81        return false;
  82}
  83
  84static int __ioremap_check_desc_other(struct resource *res)
  85{
  86        return (res->desc != IORES_DESC_NONE);
  87}
  88
  89static int __ioremap_res_check(struct resource *res, void *arg)
  90{
  91        struct ioremap_mem_flags *flags = arg;
  92
  93        if (!flags->system_ram)
  94                flags->system_ram = __ioremap_check_ram(res);
  95
  96        if (!flags->desc_other)
  97                flags->desc_other = __ioremap_check_desc_other(res);
  98
  99        return flags->system_ram && flags->desc_other;
 100}
 101
 102/*
 103 * To avoid multiple resource walks, this function walks resources marked as
 104 * IORESOURCE_MEM and IORESOURCE_BUSY and looking for system RAM and/or a
 105 * resource described not as IORES_DESC_NONE (e.g. IORES_DESC_ACPI_TABLES).
 106 */
 107static void __ioremap_check_mem(resource_size_t addr, unsigned long size,
 108                                struct ioremap_mem_flags *flags)
 109{
 110        u64 start, end;
 111
 112        start = (u64)addr;
 113        end = start + size - 1;
 114        memset(flags, 0, sizeof(*flags));
 115
 116        walk_mem_res(start, end, flags, __ioremap_res_check);
 117}
 118
 119/*
 120 * Remap an arbitrary physical address space into the kernel virtual
 121 * address space. It transparently creates kernel huge I/O mapping when
 122 * the physical address is aligned by a huge page size (1GB or 2MB) and
 123 * the requested size is at least the huge page size.
 124 *
 125 * NOTE: MTRRs can override PAT memory types with a 4KB granularity.
 126 * Therefore, the mapping code falls back to use a smaller page toward 4KB
 127 * when a mapping range is covered by non-WB type of MTRRs.
 128 *
 129 * NOTE! We need to allow non-page-aligned mappings too: we will obviously
 130 * have to convert them into an offset in a page-aligned mapping, but the
 131 * caller shouldn't need to know that small detail.
 132 */
 133static void __iomem *__ioremap_caller(resource_size_t phys_addr,
 134                unsigned long size, enum page_cache_mode pcm, void *caller)
 135{
 136        unsigned long offset, vaddr;
 137        resource_size_t last_addr;
 138        const resource_size_t unaligned_phys_addr = phys_addr;
 139        const unsigned long unaligned_size = size;
 140        struct ioremap_mem_flags mem_flags;
 141        struct vm_struct *area;
 142        enum page_cache_mode new_pcm;
 143        pgprot_t prot;
 144        int retval;
 145        void __iomem *ret_addr;
 146
 147        /* Don't allow wraparound or zero size */
 148        last_addr = phys_addr + size - 1;
 149        if (!size || last_addr < phys_addr)
 150                return NULL;
 151
 152        if (!phys_addr_valid(phys_addr)) {
 153                printk(KERN_WARNING "ioremap: invalid physical address %llx\n",
 154                       (unsigned long long)phys_addr);
 155                WARN_ON_ONCE(1);
 156                return NULL;
 157        }
 158
 159        __ioremap_check_mem(phys_addr, size, &mem_flags);
 160
 161        /*
 162         * Don't allow anybody to remap normal RAM that we're using..
 163         */
 164        if (mem_flags.system_ram) {
 165                WARN_ONCE(1, "ioremap on RAM at %pa - %pa\n",
 166                          &phys_addr, &last_addr);
 167                return NULL;
 168        }
 169
 170        /*
 171         * Mappings have to be page-aligned
 172         */
 173        offset = phys_addr & ~PAGE_MASK;
 174        phys_addr &= PHYSICAL_PAGE_MASK;
 175        size = PAGE_ALIGN(last_addr+1) - phys_addr;
 176
 177        retval = reserve_memtype(phys_addr, (u64)phys_addr + size,
 178                                                pcm, &new_pcm);
 179        if (retval) {
 180                printk(KERN_ERR "ioremap reserve_memtype failed %d\n", retval);
 181                return NULL;
 182        }
 183
 184        if (pcm != new_pcm) {
 185                if (!is_new_memtype_allowed(phys_addr, size, pcm, new_pcm)) {
 186                        printk(KERN_ERR
 187                "ioremap error for 0x%llx-0x%llx, requested 0x%x, got 0x%x\n",
 188                                (unsigned long long)phys_addr,
 189                                (unsigned long long)(phys_addr + size),
 190                                pcm, new_pcm);
 191                        goto err_free_memtype;
 192                }
 193                pcm = new_pcm;
 194        }
 195
 196        /*
 197         * If the page being mapped is in memory and SEV is active then
 198         * make sure the memory encryption attribute is enabled in the
 199         * resulting mapping.
 200         */
 201        prot = PAGE_KERNEL_IO;
 202        if (sev_active() && mem_flags.desc_other)
 203                prot = pgprot_encrypted(prot);
 204
 205        switch (pcm) {
 206        case _PAGE_CACHE_MODE_UC:
 207        default:
 208                prot = __pgprot(pgprot_val(prot) |
 209                                cachemode2protval(_PAGE_CACHE_MODE_UC));
 210                break;
 211        case _PAGE_CACHE_MODE_UC_MINUS:
 212                prot = __pgprot(pgprot_val(prot) |
 213                                cachemode2protval(_PAGE_CACHE_MODE_UC_MINUS));
 214                break;
 215        case _PAGE_CACHE_MODE_WC:
 216                prot = __pgprot(pgprot_val(prot) |
 217                                cachemode2protval(_PAGE_CACHE_MODE_WC));
 218                break;
 219        case _PAGE_CACHE_MODE_WT:
 220                prot = __pgprot(pgprot_val(prot) |
 221                                cachemode2protval(_PAGE_CACHE_MODE_WT));
 222                break;
 223        case _PAGE_CACHE_MODE_WB:
 224                break;
 225        }
 226
 227        /*
 228         * Ok, go for it..
 229         */
 230        area = get_vm_area_caller(size, VM_IOREMAP, caller);
 231        if (!area)
 232                goto err_free_memtype;
 233        area->phys_addr = phys_addr;
 234        vaddr = (unsigned long) area->addr;
 235
 236        if (kernel_map_sync_memtype(phys_addr, size, pcm))
 237                goto err_free_area;
 238
 239        if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot))
 240                goto err_free_area;
 241
 242        ret_addr = (void __iomem *) (vaddr + offset);
 243        mmiotrace_ioremap(unaligned_phys_addr, unaligned_size, ret_addr);
 244
 245        /*
 246         * Check if the request spans more than any BAR in the iomem resource
 247         * tree.
 248         */
 249        if (iomem_map_sanity_check(unaligned_phys_addr, unaligned_size))
 250                pr_warn("caller %pS mapping multiple BARs\n", caller);
 251
 252        return ret_addr;
 253err_free_area:
 254        free_vm_area(area);
 255err_free_memtype:
 256        free_memtype(phys_addr, phys_addr + size);
 257        return NULL;
 258}
 259
 260/**
 261 * ioremap_nocache     -   map bus memory into CPU space
 262 * @phys_addr:    bus address of the memory
 263 * @size:      size of the resource to map
 264 *
 265 * ioremap_nocache performs a platform specific sequence of operations to
 266 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 267 * writew/writel functions and the other mmio helpers. The returned
 268 * address is not guaranteed to be usable directly as a virtual
 269 * address.
 270 *
 271 * This version of ioremap ensures that the memory is marked uncachable
 272 * on the CPU as well as honouring existing caching rules from things like
 273 * the PCI bus. Note that there are other caches and buffers on many
 274 * busses. In particular driver authors should read up on PCI writes
 275 *
 276 * It's useful if some control registers are in such an area and
 277 * write combining or read caching is not desirable:
 278 *
 279 * Must be freed with iounmap.
 280 */
 281void __iomem *ioremap_nocache(resource_size_t phys_addr, unsigned long size)
 282{
 283        /*
 284         * Ideally, this should be:
 285         *      pat_enabled() ? _PAGE_CACHE_MODE_UC : _PAGE_CACHE_MODE_UC_MINUS;
 286         *
 287         * Till we fix all X drivers to use ioremap_wc(), we will use
 288         * UC MINUS. Drivers that are certain they need or can already
 289         * be converted over to strong UC can use ioremap_uc().
 290         */
 291        enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC_MINUS;
 292
 293        return __ioremap_caller(phys_addr, size, pcm,
 294                                __builtin_return_address(0));
 295}
 296EXPORT_SYMBOL(ioremap_nocache);
 297
 298/**
 299 * ioremap_uc     -   map bus memory into CPU space as strongly uncachable
 300 * @phys_addr:    bus address of the memory
 301 * @size:      size of the resource to map
 302 *
 303 * ioremap_uc performs a platform specific sequence of operations to
 304 * make bus memory CPU accessible via the readb/readw/readl/writeb/
 305 * writew/writel functions and the other mmio helpers. The returned
 306 * address is not guaranteed to be usable directly as a virtual
 307 * address.
 308 *
 309 * This version of ioremap ensures that the memory is marked with a strong
 310 * preference as completely uncachable on the CPU when possible. For non-PAT
 311 * systems this ends up setting page-attribute flags PCD=1, PWT=1. For PAT
 312 * systems this will set the PAT entry for the pages as strong UC.  This call
 313 * will honor existing caching rules from things like the PCI bus. Note that
 314 * there are other caches and buffers on many busses. In particular driver
 315 * authors should read up on PCI writes.
 316 *
 317 * It's useful if some control registers are in such an area and
 318 * write combining or read caching is not desirable:
 319 *
 320 * Must be freed with iounmap.
 321 */
 322void __iomem *ioremap_uc(resource_size_t phys_addr, unsigned long size)
 323{
 324        enum page_cache_mode pcm = _PAGE_CACHE_MODE_UC;
 325
 326        return __ioremap_caller(phys_addr, size, pcm,
 327                                __builtin_return_address(0));
 328}
 329EXPORT_SYMBOL_GPL(ioremap_uc);
 330
 331/**
 332 * ioremap_wc   -       map memory into CPU space write combined
 333 * @phys_addr:  bus address of the memory
 334 * @size:       size of the resource to map
 335 *
 336 * This version of ioremap ensures that the memory is marked write combining.
 337 * Write combining allows faster writes to some hardware devices.
 338 *
 339 * Must be freed with iounmap.
 340 */
 341void __iomem *ioremap_wc(resource_size_t phys_addr, unsigned long size)
 342{
 343        return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WC,
 344                                        __builtin_return_address(0));
 345}
 346EXPORT_SYMBOL(ioremap_wc);
 347
 348/**
 349 * ioremap_wt   -       map memory into CPU space write through
 350 * @phys_addr:  bus address of the memory
 351 * @size:       size of the resource to map
 352 *
 353 * This version of ioremap ensures that the memory is marked write through.
 354 * Write through stores data into memory while keeping the cache up-to-date.
 355 *
 356 * Must be freed with iounmap.
 357 */
 358void __iomem *ioremap_wt(resource_size_t phys_addr, unsigned long size)
 359{
 360        return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WT,
 361                                        __builtin_return_address(0));
 362}
 363EXPORT_SYMBOL(ioremap_wt);
 364
 365void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
 366{
 367        return __ioremap_caller(phys_addr, size, _PAGE_CACHE_MODE_WB,
 368                                __builtin_return_address(0));
 369}
 370EXPORT_SYMBOL(ioremap_cache);
 371
 372void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
 373                                unsigned long prot_val)
 374{
 375        return __ioremap_caller(phys_addr, size,
 376                                pgprot2cachemode(__pgprot(prot_val)),
 377                                __builtin_return_address(0));
 378}
 379EXPORT_SYMBOL(ioremap_prot);
 380
 381/**
 382 * iounmap - Free a IO remapping
 383 * @addr: virtual address from ioremap_*
 384 *
 385 * Caller must ensure there is only one unmapping for the same pointer.
 386 */
 387void iounmap(volatile void __iomem *addr)
 388{
 389        struct vm_struct *p, *o;
 390
 391        if ((void __force *)addr <= high_memory)
 392                return;
 393
 394        /*
 395         * The PCI/ISA range special-casing was removed from __ioremap()
 396         * so this check, in theory, can be removed. However, there are
 397         * cases where iounmap() is called for addresses not obtained via
 398         * ioremap() (vga16fb for example). Add a warning so that these
 399         * cases can be caught and fixed.
 400         */
 401        if ((void __force *)addr >= phys_to_virt(ISA_START_ADDRESS) &&
 402            (void __force *)addr < phys_to_virt(ISA_END_ADDRESS)) {
 403                WARN(1, "iounmap() called for ISA range not obtained using ioremap()\n");
 404                return;
 405        }
 406
 407        mmiotrace_iounmap(addr);
 408
 409        addr = (volatile void __iomem *)
 410                (PAGE_MASK & (unsigned long __force)addr);
 411
 412        /* Use the vm area unlocked, assuming the caller
 413           ensures there isn't another iounmap for the same address
 414           in parallel. Reuse of the virtual address is prevented by
 415           leaving it in the global lists until we're done with it.
 416           cpa takes care of the direct mappings. */
 417        p = find_vm_area((void __force *)addr);
 418
 419        if (!p) {
 420                printk(KERN_ERR "iounmap: bad address %p\n", addr);
 421                dump_stack();
 422                return;
 423        }
 424
 425        free_memtype(p->phys_addr, p->phys_addr + get_vm_area_size(p));
 426
 427        /* Finally remove it */
 428        o = remove_vm_area((void __force *)addr);
 429        BUG_ON(p != o || o == NULL);
 430        kfree(p);
 431}
 432EXPORT_SYMBOL(iounmap);
 433
 434int __init arch_ioremap_pud_supported(void)
 435{
 436#ifdef CONFIG_X86_64
 437        return boot_cpu_has(X86_FEATURE_GBPAGES);
 438#else
 439        return 0;
 440#endif
 441}
 442
 443int __init arch_ioremap_pmd_supported(void)
 444{
 445        return boot_cpu_has(X86_FEATURE_PSE);
 446}
 447
 448/*
 449 * Convert a physical pointer to a virtual kernel pointer for /dev/mem
 450 * access
 451 */
 452void *xlate_dev_mem_ptr(phys_addr_t phys)
 453{
 454        unsigned long start  = phys &  PAGE_MASK;
 455        unsigned long offset = phys & ~PAGE_MASK;
 456        void *vaddr;
 457
 458        /* memremap() maps if RAM, otherwise falls back to ioremap() */
 459        vaddr = memremap(start, PAGE_SIZE, MEMREMAP_WB);
 460
 461        /* Only add the offset on success and return NULL if memremap() failed */
 462        if (vaddr)
 463                vaddr += offset;
 464
 465        return vaddr;
 466}
 467
 468void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)
 469{
 470        memunmap((void *)((unsigned long)addr & PAGE_MASK));
 471}
 472
 473/*
 474 * Examine the physical address to determine if it is an area of memory
 475 * that should be mapped decrypted.  If the memory is not part of the
 476 * kernel usable area it was accessed and created decrypted, so these
 477 * areas should be mapped decrypted. And since the encryption key can
 478 * change across reboots, persistent memory should also be mapped
 479 * decrypted.
 480 *
 481 * If SEV is active, that implies that BIOS/UEFI also ran encrypted so
 482 * only persistent memory should be mapped decrypted.
 483 */
 484static bool memremap_should_map_decrypted(resource_size_t phys_addr,
 485                                          unsigned long size)
 486{
 487        int is_pmem;
 488
 489        /*
 490         * Check if the address is part of a persistent memory region.
 491         * This check covers areas added by E820, EFI and ACPI.
 492         */
 493        is_pmem = region_intersects(phys_addr, size, IORESOURCE_MEM,
 494                                    IORES_DESC_PERSISTENT_MEMORY);
 495        if (is_pmem != REGION_DISJOINT)
 496                return true;
 497
 498        /*
 499         * Check if the non-volatile attribute is set for an EFI
 500         * reserved area.
 501         */
 502        if (efi_enabled(EFI_BOOT)) {
 503                switch (efi_mem_type(phys_addr)) {
 504                case EFI_RESERVED_TYPE:
 505                        if (efi_mem_attributes(phys_addr) & EFI_MEMORY_NV)
 506                                return true;
 507                        break;
 508                default:
 509                        break;
 510                }
 511        }
 512
 513        /* Check if the address is outside kernel usable area */
 514        switch (e820__get_entry_type(phys_addr, phys_addr + size - 1)) {
 515        case E820_TYPE_RESERVED:
 516        case E820_TYPE_ACPI:
 517        case E820_TYPE_NVS:
 518        case E820_TYPE_UNUSABLE:
 519                /* For SEV, these areas are encrypted */
 520                if (sev_active())
 521                        break;
 522                /* Fallthrough */
 523
 524        case E820_TYPE_PRAM:
 525                return true;
 526        default:
 527                break;
 528        }
 529
 530        return false;
 531}
 532
 533/*
 534 * Examine the physical address to determine if it is EFI data. Check
 535 * it against the boot params structure and EFI tables and memory types.
 536 */
 537static bool memremap_is_efi_data(resource_size_t phys_addr,
 538                                 unsigned long size)
 539{
 540        u64 paddr;
 541
 542        /* Check if the address is part of EFI boot/runtime data */
 543        if (!efi_enabled(EFI_BOOT))
 544                return false;
 545
 546        paddr = boot_params.efi_info.efi_memmap_hi;
 547        paddr <<= 32;
 548        paddr |= boot_params.efi_info.efi_memmap;
 549        if (phys_addr == paddr)
 550                return true;
 551
 552        paddr = boot_params.efi_info.efi_systab_hi;
 553        paddr <<= 32;
 554        paddr |= boot_params.efi_info.efi_systab;
 555        if (phys_addr == paddr)
 556                return true;
 557
 558        if (efi_is_table_address(phys_addr))
 559                return true;
 560
 561        switch (efi_mem_type(phys_addr)) {
 562        case EFI_BOOT_SERVICES_DATA:
 563        case EFI_RUNTIME_SERVICES_DATA:
 564                return true;
 565        default:
 566                break;
 567        }
 568
 569        return false;
 570}
 571
 572/*
 573 * Examine the physical address to determine if it is boot data by checking
 574 * it against the boot params setup_data chain.
 575 */
 576static bool memremap_is_setup_data(resource_size_t phys_addr,
 577                                   unsigned long size)
 578{
 579        struct setup_data *data;
 580        u64 paddr, paddr_next;
 581
 582        paddr = boot_params.hdr.setup_data;
 583        while (paddr) {
 584                unsigned int len;
 585
 586                if (phys_addr == paddr)
 587                        return true;
 588
 589                data = memremap(paddr, sizeof(*data),
 590                                MEMREMAP_WB | MEMREMAP_DEC);
 591
 592                paddr_next = data->next;
 593                len = data->len;
 594
 595                memunmap(data);
 596
 597                if ((phys_addr > paddr) && (phys_addr < (paddr + len)))
 598                        return true;
 599
 600                paddr = paddr_next;
 601        }
 602
 603        return false;
 604}
 605
 606/*
 607 * Examine the physical address to determine if it is boot data by checking
 608 * it against the boot params setup_data chain (early boot version).
 609 */
 610static bool __init early_memremap_is_setup_data(resource_size_t phys_addr,
 611                                                unsigned long size)
 612{
 613        struct setup_data *data;
 614        u64 paddr, paddr_next;
 615
 616        paddr = boot_params.hdr.setup_data;
 617        while (paddr) {
 618                unsigned int len;
 619
 620                if (phys_addr == paddr)
 621                        return true;
 622
 623                data = early_memremap_decrypted(paddr, sizeof(*data));
 624
 625                paddr_next = data->next;
 626                len = data->len;
 627
 628                early_memunmap(data, sizeof(*data));
 629
 630                if ((phys_addr > paddr) && (phys_addr < (paddr + len)))
 631                        return true;
 632
 633                paddr = paddr_next;
 634        }
 635
 636        return false;
 637}
 638
 639/*
 640 * Architecture function to determine if RAM remap is allowed. By default, a
 641 * RAM remap will map the data as encrypted. Determine if a RAM remap should
 642 * not be done so that the data will be mapped decrypted.
 643 */
 644bool arch_memremap_can_ram_remap(resource_size_t phys_addr, unsigned long size,
 645                                 unsigned long flags)
 646{
 647        if (!mem_encrypt_active())
 648                return true;
 649
 650        if (flags & MEMREMAP_ENC)
 651                return true;
 652
 653        if (flags & MEMREMAP_DEC)
 654                return false;
 655
 656        if (sme_active()) {
 657                if (memremap_is_setup_data(phys_addr, size) ||
 658                    memremap_is_efi_data(phys_addr, size))
 659                        return false;
 660        }
 661
 662        return !memremap_should_map_decrypted(phys_addr, size);
 663}
 664
 665/*
 666 * Architecture override of __weak function to adjust the protection attributes
 667 * used when remapping memory. By default, early_memremap() will map the data
 668 * as encrypted. Determine if an encrypted mapping should not be done and set
 669 * the appropriate protection attributes.
 670 */
 671pgprot_t __init early_memremap_pgprot_adjust(resource_size_t phys_addr,
 672                                             unsigned long size,
 673                                             pgprot_t prot)
 674{
 675        bool encrypted_prot;
 676
 677        if (!mem_encrypt_active())
 678                return prot;
 679
 680        encrypted_prot = true;
 681
 682        if (sme_active()) {
 683                if (early_memremap_is_setup_data(phys_addr, size) ||
 684                    memremap_is_efi_data(phys_addr, size))
 685                        encrypted_prot = false;
 686        }
 687
 688        if (encrypted_prot && memremap_should_map_decrypted(phys_addr, size))
 689                encrypted_prot = false;
 690
 691        return encrypted_prot ? pgprot_encrypted(prot)
 692                              : pgprot_decrypted(prot);
 693}
 694
 695bool phys_mem_access_encrypted(unsigned long phys_addr, unsigned long size)
 696{
 697        return arch_memremap_can_ram_remap(phys_addr, size, 0);
 698}
 699
 700#ifdef CONFIG_ARCH_USE_MEMREMAP_PROT
 701/* Remap memory with encryption */
 702void __init *early_memremap_encrypted(resource_size_t phys_addr,
 703                                      unsigned long size)
 704{
 705        return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC);
 706}
 707
 708/*
 709 * Remap memory with encryption and write-protected - cannot be called
 710 * before pat_init() is called
 711 */
 712void __init *early_memremap_encrypted_wp(resource_size_t phys_addr,
 713                                         unsigned long size)
 714{
 715        /* Be sure the write-protect PAT entry is set for write-protect */
 716        if (__pte2cachemode_tbl[_PAGE_CACHE_MODE_WP] != _PAGE_CACHE_MODE_WP)
 717                return NULL;
 718
 719        return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_ENC_WP);
 720}
 721
 722/* Remap memory without encryption */
 723void __init *early_memremap_decrypted(resource_size_t phys_addr,
 724                                      unsigned long size)
 725{
 726        return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC);
 727}
 728
 729/*
 730 * Remap memory without encryption and write-protected - cannot be called
 731 * before pat_init() is called
 732 */
 733void __init *early_memremap_decrypted_wp(resource_size_t phys_addr,
 734                                         unsigned long size)
 735{
 736        /* Be sure the write-protect PAT entry is set for write-protect */
 737        if (__pte2cachemode_tbl[_PAGE_CACHE_MODE_WP] != _PAGE_CACHE_MODE_WP)
 738                return NULL;
 739
 740        return early_memremap_prot(phys_addr, size, __PAGE_KERNEL_NOENC_WP);
 741}
 742#endif  /* CONFIG_ARCH_USE_MEMREMAP_PROT */
 743
 744static pte_t bm_pte[PAGE_SIZE/sizeof(pte_t)] __page_aligned_bss;
 745
 746static inline pmd_t * __init early_ioremap_pmd(unsigned long addr)
 747{
 748        /* Don't assume we're using swapper_pg_dir at this point */
 749        pgd_t *base = __va(read_cr3_pa());
 750        pgd_t *pgd = &base[pgd_index(addr)];
 751        p4d_t *p4d = p4d_offset(pgd, addr);
 752        pud_t *pud = pud_offset(p4d, addr);
 753        pmd_t *pmd = pmd_offset(pud, addr);
 754
 755        return pmd;
 756}
 757
 758static inline pte_t * __init early_ioremap_pte(unsigned long addr)
 759{
 760        return &bm_pte[pte_index(addr)];
 761}
 762
 763bool __init is_early_ioremap_ptep(pte_t *ptep)
 764{
 765        return ptep >= &bm_pte[0] && ptep < &bm_pte[PAGE_SIZE/sizeof(pte_t)];
 766}
 767
 768void __init early_ioremap_init(void)
 769{
 770        pmd_t *pmd;
 771
 772#ifdef CONFIG_X86_64
 773        BUILD_BUG_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
 774#else
 775        WARN_ON((fix_to_virt(0) + PAGE_SIZE) & ((1 << PMD_SHIFT) - 1));
 776#endif
 777
 778        early_ioremap_setup();
 779
 780        pmd = early_ioremap_pmd(fix_to_virt(FIX_BTMAP_BEGIN));
 781        memset(bm_pte, 0, sizeof(bm_pte));
 782        pmd_populate_kernel(&init_mm, pmd, bm_pte);
 783
 784        /*
 785         * The boot-ioremap range spans multiple pmds, for which
 786         * we are not prepared:
 787         */
 788#define __FIXADDR_TOP (-PAGE_SIZE)
 789        BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
 790                     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));
 791#undef __FIXADDR_TOP
 792        if (pmd != early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END))) {
 793                WARN_ON(1);
 794                printk(KERN_WARNING "pmd %p != %p\n",
 795                       pmd, early_ioremap_pmd(fix_to_virt(FIX_BTMAP_END)));
 796                printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
 797                        fix_to_virt(FIX_BTMAP_BEGIN));
 798                printk(KERN_WARNING "fix_to_virt(FIX_BTMAP_END):   %08lx\n",
 799                        fix_to_virt(FIX_BTMAP_END));
 800
 801                printk(KERN_WARNING "FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
 802                printk(KERN_WARNING "FIX_BTMAP_BEGIN:     %d\n",
 803                       FIX_BTMAP_BEGIN);
 804        }
 805}
 806
 807void __init __early_set_fixmap(enum fixed_addresses idx,
 808                               phys_addr_t phys, pgprot_t flags)
 809{
 810        unsigned long addr = __fix_to_virt(idx);
 811        pte_t *pte;
 812
 813        if (idx >= __end_of_fixed_addresses) {
 814                BUG();
 815                return;
 816        }
 817        pte = early_ioremap_pte(addr);
 818
 819        /* Sanitize 'prot' against any unsupported bits: */
 820        pgprot_val(flags) &= __default_kernel_pte_mask;
 821
 822        if (pgprot_val(flags))
 823                set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
 824        else
 825                pte_clear(&init_mm, addr, pte);
 826        __flush_tlb_one_kernel(addr);
 827}
 828