arch/x86/platform/efi/efi_64.c

   1 /*
   2  * x86_64 specific EFI support functions
   3  * Based on Extensible Firmware Interface Specification version 1.0
   4  *
   5  * Copyright (C) 2005-2008 Intel Co.
   6  *      Fenghua Yu <fenghua.yu@intel.com>
   7  *      Bibo Mao <bibo.mao@intel.com>
   8  *      Chandramouli Narayanan <mouli@linux.intel.com>
   9  *      Huang Ying <ying.huang@intel.com>
  10  *
  11  * Code to convert EFI to E820 map has been implemented in elilo bootloader
  12  * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
  13  * is setup appropriately for EFI runtime code.
  14  * - mouli 06/14/2007.
  15  *
  16  */
  17
  18 #define pr_fmt(fmt) "efi: " fmt
  19
  20 #include <linux/kernel.h>
  21 #include <linux/init.h>
  22 #include <linux/mm.h>
  23 #include <linux/types.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/bootmem.h>
  26 #include <linux/ioport.h>
  27 #include <linux/init.h>
  28 #include <linux/mc146818rtc.h>
  29 #include <linux/efi.h>
  30 #include <linux/uaccess.h>
  31 #include <linux/io.h>
  32 #include <linux/reboot.h>
  33 #include <linux/slab.h>
  34 #include <linux/ucs2_string.h>
  35
  36 #include <asm/setup.h>
  37 #include <asm/page.h>
  38 #include <asm/e820.h>
  39 #include <asm/pgtable.h>
  40 #include <asm/tlbflush.h>
  41 #include <asm/proto.h>
  42 #include <asm/efi.h>
  43 #include <asm/cacheflush.h>
  44 #include <asm/fixmap.h>
  45 #include <asm/realmode.h>
  46 #include <asm/time.h>
  47 #include <asm/pgalloc.h>
  48 #include <asm/sections.h>
  49
  50 /*
  51  * We allocate runtime services regions bottom-up, starting from -4G, i.e.
  52  * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
  53  */
  54 static u64 efi_va = EFI_VA_START;
  55
  56 struct efi_scratch efi_scratch;
  57
  58 static void __init early_code_mapping_set_exec(int executable)
  59 {
  60         efi_memory_desc_t *md;
  61
  62         if (!(__supported_pte_mask & _PAGE_NX))
  63                 return;
  64
  65         /* Make EFI service code area executable */
  66         for_each_efi_memory_desc(md) {
  67                 if (md->type == EFI_RUNTIME_SERVICES_CODE ||
  68                     md->type == EFI_BOOT_SERVICES_CODE)
  69                         efi_set_executable(md, executable);
  70         }
  71 }
  72
  73 pgd_t * __init efi_call_phys_prolog(void)
  74 {
  75         unsigned long vaddress;
  76         pgd_t *save_pgd;
  77
  78         int pgd;
  79         int n_pgds;
  80
  81         if (!efi_enabled(EFI_OLD_MEMMAP)) {
  82                 save_pgd = (pgd_t *)read_cr3();
  83                 write_cr3((unsigned long)efi_scratch.efi_pgt);
  84                 goto out;
  85         }
  86
  87         early_code_mapping_set_exec(1);
  88
  89         n_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT), PGDIR_SIZE);
  90         save_pgd = kmalloc_array(n_pgds, sizeof(*save_pgd), GFP_KERNEL);
  91
  92         for (pgd = 0; pgd < n_pgds; pgd++) {
  93                 save_pgd[pgd] = *pgd_offset_k(pgd * PGDIR_SIZE);
  94                 vaddress = (unsigned long)__va(pgd * PGDIR_SIZE);
  95                 set_pgd(pgd_offset_k(pgd * PGDIR_SIZE), *pgd_offset_k(vaddress));
  96         }
  97 out:
  98         __flush_tlb_all();
  99
 100         return save_pgd;
 101 }
 102
 103 void __init efi_call_phys_epilog(pgd_t *save_pgd)
 104 {
 105         /*
 106          * After the lock is released, the original page table is restored.
 107          */
 108         int pgd_idx;
 109         int nr_pgds;
 110
 111         if (!efi_enabled(EFI_OLD_MEMMAP)) {
 112                 write_cr3((unsigned long)save_pgd);
 113                 __flush_tlb_all();
 114                 return;
 115         }
 116
 117         nr_pgds = DIV_ROUND_UP((max_pfn << PAGE_SHIFT) , PGDIR_SIZE);
 118
 119         for (pgd_idx = 0; pgd_idx < nr_pgds; pgd_idx++)
 120                 set_pgd(pgd_offset_k(pgd_idx * PGDIR_SIZE), save_pgd[pgd_idx]);
 121
 122         kfree(save_pgd);
 123
 124         __flush_tlb_all();
 125         early_code_mapping_set_exec(0);
 126 }
 127
 128 static pgd_t *efi_pgd;
 129
 130 /*
 131  * We need our own copy of the higher levels of the page tables
 132  * because we want to avoid inserting EFI region mappings (EFI_VA_END
 133  * to EFI_VA_START) into the standard kernel page tables. Everything
 134  * else can be shared, see efi_sync_low_kernel_mappings().
 135  */
 136 int __init efi_alloc_page_tables(void)
 137 {
 138         pgd_t *pgd;
 139         pud_t *pud;
 140         gfp_t gfp_mask;
 141
 142         if (efi_enabled(EFI_OLD_MEMMAP))
 143                 return 0;
 144
 145         gfp_mask = GFP_KERNEL | __GFP_NOTRACK | __GFP_ZERO;
 146         efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER);
 147         if (!efi_pgd)
 148                 return -ENOMEM;
 149
 150         pgd = efi_pgd + pgd_index(EFI_VA_END);
 151
 152         pud = pud_alloc_one(NULL, 0);
 153         if (!pud) {
 154                 free_page((unsigned long)efi_pgd);
 155                 return -ENOMEM;
 156         }
 157
 158         pgd_populate(NULL, pgd, pud);
 159
 160         return 0;
 161 }
 162
 163 /*
 164  * Add low kernel mappings for passing arguments to EFI functions.
 165  */
 166 void efi_sync_low_kernel_mappings(void)
 167 {
 168         unsigned num_entries;
 169         pgd_t *pgd_k, *pgd_efi;
 170         pud_t *pud_k, *pud_efi;
 171
 172         if (efi_enabled(EFI_OLD_MEMMAP))
 173                 return;
 174
 175         /*
 176          * We can share all PGD entries apart from the one entry that
 177          * covers the EFI runtime mapping space.
 178          *
 179          * Make sure the EFI runtime region mappings are guaranteed to
 180          * only span a single PGD entry and that the entry also maps
 181          * other important kernel regions.
 182          */
 183         BUILD_BUG_ON(pgd_index(EFI_VA_END) != pgd_index(MODULES_END));
 184         BUILD_BUG_ON((EFI_VA_START & PGDIR_MASK) !=
 185                         (EFI_VA_END & PGDIR_MASK));
 186
 187         pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET);
 188         pgd_k = pgd_offset_k(PAGE_OFFSET);
 189
 190         num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET);
 191         memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries);
 192
 193         /*
 194          * We share all the PUD entries apart from those that map the
 195          * EFI regions. Copy around them.
 196          */
 197         BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0);
 198         BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0);
 199
 200         pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
 201         pud_efi = pud_offset(pgd_efi, 0);
 202
 203         pgd_k = pgd_offset_k(EFI_VA_END);
 204         pud_k = pud_offset(pgd_k, 0);
 205
 206         num_entries = pud_index(EFI_VA_END);
 207         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 208
 209         pud_efi = pud_offset(pgd_efi, EFI_VA_START);
 210         pud_k = pud_offset(pgd_k, EFI_VA_START);
 211
 212         num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START);
 213         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 214 }
 215
 216 /*
 217  * Wrapper for slow_virt_to_phys() that handles NULL addresses.
 218  */
 219 static inline phys_addr_t
 220 virt_to_phys_or_null_size(void *va, unsigned long size)
 221 {
 222         bool bad_size;
 223
 224         if (!va)
 225                 return 0;
 226
 227         if (virt_addr_valid(va))
 228                 return virt_to_phys(va);
 229
 230         /*
 231          * A fully aligned variable on the stack is guaranteed not to
 232          * cross a page bounary. Try to catch strings on the stack by
 233          * checking that 'size' is a power of two.
 234          */
 235         bad_size = size > PAGE_SIZE || !is_power_of_2(size);
 236
 237         WARN_ON(!IS_ALIGNED((unsigned long)va, size) || bad_size);
 238
 239         return slow_virt_to_phys(va);
 240 }
 241
 242 #define virt_to_phys_or_null(addr)                              \
 243         virt_to_phys_or_null_size((addr), sizeof(*(addr)))
 244
 245 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 246 {
 247         unsigned long pfn, text;
 248         struct page *page;
 249         unsigned npages;
 250         pgd_t *pgd;
 251
 252         if (efi_enabled(EFI_OLD_MEMMAP))
 253                 return 0;
 254
 255         efi_scratch.efi_pgt = (pgd_t *)__pa(efi_pgd);
 256         pgd = efi_pgd;
 257
 258         /*
 259          * It can happen that the physical address of new_memmap lands in memory
 260          * which is not mapped in the EFI page table. Therefore we need to go
 261          * and ident-map those pages containing the map before calling
 262          * phys_efi_set_virtual_address_map().
 263          */
 264         pfn = pa_memmap >> PAGE_SHIFT;
 265         if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, _PAGE_NX | _PAGE_RW)) {
 266                 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
 267                 return 1;
 268         }
 269
 270         efi_scratch.use_pgd = true;
 271
 272         /*
 273          * Certain firmware versions are way too sentimential and still believe
 274          * they are exclusive and unquestionable owners of the first physical page,
 275          * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
 276          * (but then write-access it later during SetVirtualAddressMap()).
 277          *
 278          * Create a 1:1 mapping for this page, to avoid triple faults during early
 279          * boot with such firmware. We are free to hand this page to the BIOS,
 280          * as trim_bios_range() will reserve the first page and isolate it away
 281          * from memory allocators anyway.
 282          */
 283         if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, _PAGE_RW)) {
 284                 pr_err("Failed to create 1:1 mapping for the first page!\n");
 285                 return 1;
 286         }
 287
 288         /*
 289          * When making calls to the firmware everything needs to be 1:1
 290          * mapped and addressable with 32-bit pointers. Map the kernel
 291          * text and allocate a new stack because we can't rely on the
 292          * stack pointer being < 4GB.
 293          */
 294         if (!IS_ENABLED(CONFIG_EFI_MIXED) || efi_is_native())
 295                 return 0;
 296
 297         page = alloc_page(GFP_KERNEL|__GFP_DMA32);
 298         if (!page)
 299                 panic("Unable to allocate EFI runtime stack < 4GB\n");
 300
 301         efi_scratch.phys_stack = virt_to_phys(page_address(page));
 302         efi_scratch.phys_stack += PAGE_SIZE; /* stack grows down */
 303
 304         npages = (_etext - _text) >> PAGE_SHIFT;
 305         text = __pa(_text);
 306         pfn = text >> PAGE_SHIFT;
 307
 308         if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, _PAGE_RW)) {
 309                 pr_err("Failed to map kernel text 1:1\n");
 310                 return 1;
 311         }
 312
 313         return 0;
 314 }
 315
 316 static void __init __map_region(efi_memory_desc_t *md, u64 va)
 317 {
 318         unsigned long flags = _PAGE_RW;
 319         unsigned long pfn;
 320         pgd_t *pgd = efi_pgd;
 321
 322         if (!(md->attribute & EFI_MEMORY_WB))
 323                 flags |= _PAGE_PCD;
 324
 325         pfn = md->phys_addr >> PAGE_SHIFT;
 326         if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags))
 327                 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
 328                            md->phys_addr, va);
 329 }
 330
 331 void __init efi_map_region(efi_memory_desc_t *md)
 332 {
 333         unsigned long size = md->num_pages << PAGE_SHIFT;
 334         u64 pa = md->phys_addr;
 335
 336         if (efi_enabled(EFI_OLD_MEMMAP))
 337                 return old_map_region(md);
 338
 339         /*
 340          * Make sure the 1:1 mappings are present as a catch-all for b0rked
 341          * firmware which doesn't update all internal pointers after switching
 342          * to virtual mode and would otherwise crap on us.
 343          */
 344         __map_region(md, md->phys_addr);
 345
 346         /*
 347          * Enforce the 1:1 mapping as the default virtual address when
 348          * booting in EFI mixed mode, because even though we may be
 349          * running a 64-bit kernel, the firmware may only be 32-bit.
 350          */
 351         if (!efi_is_native () && IS_ENABLED(CONFIG_EFI_MIXED)) {
 352                 md->virt_addr = md->phys_addr;
 353                 return;
 354         }
 355
 356         efi_va -= size;
 357
 358         /* Is PA 2M-aligned? */
 359         if (!(pa & (PMD_SIZE - 1))) {
 360                 efi_va &= PMD_MASK;
 361         } else {
 362                 u64 pa_offset = pa & (PMD_SIZE - 1);
 363                 u64 prev_va = efi_va;
 364
 365                 /* get us the same offset within this 2M page */
 366                 efi_va = (efi_va & PMD_MASK) + pa_offset;
 367
 368                 if (efi_va > prev_va)
 369                         efi_va -= PMD_SIZE;
 370         }
 371
 372         if (efi_va < EFI_VA_END) {
 373                 pr_warn(FW_WARN "VA address range overflow!\n");
 374                 return;
 375         }
 376
 377         /* Do the VA map */
 378         __map_region(md, efi_va);
 379         md->virt_addr = efi_va;
 380 }
 381
 382 /*
 383  * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
 384  * md->virt_addr is the original virtual address which had been mapped in kexec
 385  * 1st kernel.
 386  */
 387 void __init efi_map_region_fixed(efi_memory_desc_t *md)
 388 {
 389         __map_region(md, md->phys_addr);
 390         __map_region(md, md->virt_addr);
 391 }
 392
 393 void __iomem *__init efi_ioremap(unsigned long phys_addr, unsigned long size,
 394                                  u32 type, u64 attribute)
 395 {
 396         unsigned long last_map_pfn;
 397
 398         if (type == EFI_MEMORY_MAPPED_IO)
 399                 return ioremap(phys_addr, size);
 400
 401         last_map_pfn = init_memory_mapping(phys_addr, phys_addr + size);
 402         if ((last_map_pfn << PAGE_SHIFT) < phys_addr + size) {
 403                 unsigned long top = last_map_pfn << PAGE_SHIFT;
 404                 efi_ioremap(top, size - (top - phys_addr), type, attribute);
 405         }
 406
 407         if (!(attribute & EFI_MEMORY_WB))
 408                 efi_memory_uc((u64)(unsigned long)__va(phys_addr), size);
 409
 410         return (void __iomem *)__va(phys_addr);
 411 }
 412
 413 void __init parse_efi_setup(u64 phys_addr, u32 data_len)
 414 {
 415         efi_setup = phys_addr + sizeof(struct setup_data);
 416 }
 417
 418 void __init efi_runtime_update_mappings(void)
 419 {
 420         unsigned long pfn;
 421         pgd_t *pgd = efi_pgd;
 422         efi_memory_desc_t *md;
 423
 424         if (efi_enabled(EFI_OLD_MEMMAP)) {
 425                 if (__supported_pte_mask & _PAGE_NX)
 426                         runtime_code_page_mkexec();
 427                 return;
 428         }
 429
 430         if (!efi_enabled(EFI_NX_PE_DATA))
 431                 return;
 432
 433         for_each_efi_memory_desc(md) {
 434                 unsigned long pf = 0;
 435
 436                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
 437                         continue;
 438
 439                 if (!(md->attribute & EFI_MEMORY_WB))
 440                         pf |= _PAGE_PCD;
 441
 442                 if ((md->attribute & EFI_MEMORY_XP) ||
 443                         (md->type == EFI_RUNTIME_SERVICES_DATA))
 444                         pf |= _PAGE_NX;
 445
 446                 if (!(md->attribute & EFI_MEMORY_RO) &&
 447                         (md->type != EFI_RUNTIME_SERVICES_CODE))
 448                         pf |= _PAGE_RW;
 449
 450                 /* Update the 1:1 mapping */
 451                 pfn = md->phys_addr >> PAGE_SHIFT;
 452                 if (kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf))
 453                         pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
 454                                    md->phys_addr, md->virt_addr);
 455
 456                 if (kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf))
 457                         pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
 458                                    md->phys_addr, md->virt_addr);
 459         }
 460 }
 461
 462 void __init efi_dump_pagetable(void)
 463 {
 464 #ifdef CONFIG_EFI_PGT_DUMP
 465         ptdump_walk_pgd_level(NULL, efi_pgd);
 466 #endif
 467 }
 468
 469 #ifdef CONFIG_EFI_MIXED
 470 extern efi_status_t efi64_thunk(u32, ...);
 471
 472 #define runtime_service32(func)                                          \
 473 ({                                                                       \
 474         u32 table = (u32)(unsigned long)efi.systab;                      \
 475         u32 *rt, *___f;                                                  \
 476                                                                          \
 477         rt = (u32 *)(table + offsetof(efi_system_table_32_t, runtime));  \
 478         ___f = (u32 *)(*rt + offsetof(efi_runtime_services_32_t, func)); \
 479         *___f;                                                           \
 480 })
 481
 482 /*
 483  * Switch to the EFI page tables early so that we can access the 1:1
 484  * runtime services mappings which are not mapped in any other page
 485  * tables. This function must be called before runtime_service32().
 486  *
 487  * Also, disable interrupts because the IDT points to 64-bit handlers,
 488  * which aren't going to function correctly when we switch to 32-bit.
 489  */
 490 #define efi_thunk(f, ...)                                               \
 491 ({                                                                      \
 492         efi_status_t __s;                                               \
 493         unsigned long __flags;                                          \
 494         u32 __func;                                                     \
 495                                                                         \
 496         local_irq_save(__flags);                                        \
 497         arch_efi_call_virt_setup();                                     \
 498                                                                         \
 499         __func = runtime_service32(f);                                  \
 500         __s = efi64_thunk(__func, __VA_ARGS__);                         \
 501                                                                         \
 502         arch_efi_call_virt_teardown();                                  \
 503         local_irq_restore(__flags);                                     \
 504                                                                         \
 505         __s;                                                            \
 506 })
 507
 508 efi_status_t efi_thunk_set_virtual_address_map(
 509         void *phys_set_virtual_address_map,
 510         unsigned long memory_map_size,
 511         unsigned long descriptor_size,
 512         u32 descriptor_version,
 513         efi_memory_desc_t *virtual_map)
 514 {
 515         efi_status_t status;
 516         unsigned long flags;
 517         u32 func;
 518
 519         efi_sync_low_kernel_mappings();
 520         local_irq_save(flags);
 521
 522         efi_scratch.prev_cr3 = read_cr3();
 523         write_cr3((unsigned long)efi_scratch.efi_pgt);
 524         __flush_tlb_all();
 525
 526         func = (u32)(unsigned long)phys_set_virtual_address_map;
 527         status = efi64_thunk(func, memory_map_size, descriptor_size,
 528                              descriptor_version, virtual_map);
 529
 530         write_cr3(efi_scratch.prev_cr3);
 531         __flush_tlb_all();
 532         local_irq_restore(flags);
 533
 534         return status;
 535 }
 536
 537 static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 538 {
 539         efi_status_t status;
 540         u32 phys_tm, phys_tc;
 541
 542         spin_lock(&rtc_lock);
 543
 544         phys_tm = virt_to_phys_or_null(tm);
 545         phys_tc = virt_to_phys_or_null(tc);
 546
 547         status = efi_thunk(get_time, phys_tm, phys_tc);
 548
 549         spin_unlock(&rtc_lock);
 550
 551         return status;
 552 }
 553
 554 static efi_status_t efi_thunk_set_time(efi_time_t *tm)
 555 {
 556         efi_status_t status;
 557         u32 phys_tm;
 558
 559         spin_lock(&rtc_lock);
 560
 561         phys_tm = virt_to_phys_or_null(tm);
 562
 563         status = efi_thunk(set_time, phys_tm);
 564
 565         spin_unlock(&rtc_lock);
 566
 567         return status;
 568 }
 569
 570 static efi_status_t
 571 efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
 572                           efi_time_t *tm)
 573 {
 574         efi_status_t status;
 575         u32 phys_enabled, phys_pending, phys_tm;
 576
 577         spin_lock(&rtc_lock);
 578
 579         phys_enabled = virt_to_phys_or_null(enabled);
 580         phys_pending = virt_to_phys_or_null(pending);
 581         phys_tm = virt_to_phys_or_null(tm);
 582
 583         status = efi_thunk(get_wakeup_time, phys_enabled,
 584                              phys_pending, phys_tm);
 585
 586         spin_unlock(&rtc_lock);
 587
 588         return status;
 589 }
 590
 591 static efi_status_t
 592 efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 593 {
 594         efi_status_t status;
 595         u32 phys_tm;
 596
 597         spin_lock(&rtc_lock);
 598
 599         phys_tm = virt_to_phys_or_null(tm);
 600
 601         status = efi_thunk(set_wakeup_time, enabled, phys_tm);
 602
 603         spin_unlock(&rtc_lock);
 604
 605         return status;
 606 }
 607
 608 static unsigned long efi_name_size(efi_char16_t *name)
 609 {
 610         return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1;
 611 }
 612
 613 static efi_status_t
 614 efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
 615                        u32 *attr, unsigned long *data_size, void *data)
 616 {
 617         efi_status_t status;
 618         u32 phys_name, phys_vendor, phys_attr;
 619         u32 phys_data_size, phys_data;
 620
 621         phys_data_size = virt_to_phys_or_null(data_size);
 622         phys_vendor = virt_to_phys_or_null(vendor);
 623         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 624         phys_attr = virt_to_phys_or_null(attr);
 625         phys_data = virt_to_phys_or_null_size(data, *data_size);
 626
 627         status = efi_thunk(get_variable, phys_name, phys_vendor,
 628                            phys_attr, phys_data_size, phys_data);
 629
 630         return status;
 631 }
 632
 633 static efi_status_t
 634 efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
 635                        u32 attr, unsigned long data_size, void *data)
 636 {
 637         u32 phys_name, phys_vendor, phys_data;
 638         efi_status_t status;
 639
 640         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 641         phys_vendor = virt_to_phys_or_null(vendor);
 642         phys_data = virt_to_phys_or_null_size(data, data_size);
 643
 644         /* If data_size is > sizeof(u32) we've got problems */
 645         status = efi_thunk(set_variable, phys_name, phys_vendor,
 646                            attr, data_size, phys_data);
 647
 648         return status;
 649 }
 650
 651 static efi_status_t
 652 efi_thunk_get_next_variable(unsigned long *name_size,
 653                             efi_char16_t *name,
 654                             efi_guid_t *vendor)
 655 {
 656         efi_status_t status;
 657         u32 phys_name_size, phys_name, phys_vendor;
 658
 659         phys_name_size = virt_to_phys_or_null(name_size);
 660         phys_vendor = virt_to_phys_or_null(vendor);
 661         phys_name = virt_to_phys_or_null_size(name, *name_size);
 662
 663         status = efi_thunk(get_next_variable, phys_name_size,
 664                            phys_name, phys_vendor);
 665
 666         return status;
 667 }
 668
 669 static efi_status_t
 670 efi_thunk_get_next_high_mono_count(u32 *count)
 671 {
 672         efi_status_t status;
 673         u32 phys_count;
 674
 675         phys_count = virt_to_phys_or_null(count);
 676         status = efi_thunk(get_next_high_mono_count, phys_count);
 677
 678         return status;
 679 }
 680
 681 static void
 682 efi_thunk_reset_system(int reset_type, efi_status_t status,
 683                        unsigned long data_size, efi_char16_t *data)
 684 {
 685         u32 phys_data;
 686
 687         phys_data = virt_to_phys_or_null_size(data, data_size);
 688
 689         efi_thunk(reset_system, reset_type, status, data_size, phys_data);
 690 }
 691
 692 static efi_status_t
 693 efi_thunk_update_capsule(efi_capsule_header_t **capsules,
 694                          unsigned long count, unsigned long sg_list)
 695 {
 696         /*
 697          * To properly support this function we would need to repackage
 698          * 'capsules' because the firmware doesn't understand 64-bit
 699          * pointers.
 700          */
 701         return EFI_UNSUPPORTED;
 702 }
 703
 704 static efi_status_t
 705 efi_thunk_query_variable_info(u32 attr, u64 *storage_space,
 706                               u64 *remaining_space,
 707                               u64 *max_variable_size)
 708 {
 709         efi_status_t status;
 710         u32 phys_storage, phys_remaining, phys_max;
 711
 712         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 713                 return EFI_UNSUPPORTED;
 714
 715         phys_storage = virt_to_phys_or_null(storage_space);
 716         phys_remaining = virt_to_phys_or_null(remaining_space);
 717         phys_max = virt_to_phys_or_null(max_variable_size);
 718
 719         status = efi_thunk(query_variable_info, attr, phys_storage,
 720                            phys_remaining, phys_max);
 721
 722         return status;
 723 }
 724
 725 static efi_status_t
 726 efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
 727                              unsigned long count, u64 *max_size,
 728                              int *reset_type)
 729 {
 730         /*
 731          * To properly support this function we would need to repackage
 732          * 'capsules' because the firmware doesn't understand 64-bit
 733          * pointers.
 734          */
 735         return EFI_UNSUPPORTED;
 736 }
 737
 738 void efi_thunk_runtime_setup(void)
 739 {
 740         efi.get_time = efi_thunk_get_time;
 741         efi.set_time = efi_thunk_set_time;
 742         efi.get_wakeup_time = efi_thunk_get_wakeup_time;
 743         efi.set_wakeup_time = efi_thunk_set_wakeup_time;
 744         efi.get_variable = efi_thunk_get_variable;
 745         efi.get_next_variable = efi_thunk_get_next_variable;
 746         efi.set_variable = efi_thunk_set_variable;
 747         efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count;
 748         efi.reset_system = efi_thunk_reset_system;
 749         efi.query_variable_info = efi_thunk_query_variable_info;
 750         efi.update_capsule = efi_thunk_update_capsule;
 751         efi.query_capsule_caps = efi_thunk_query_capsule_caps;
 752 }
 753 #endif /* CONFIG_EFI_MIXED */