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