arch/x86/platform/efi/efi_64.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * x86_64 specific EFI support functions
   4  * Based on Extensible Firmware Interface Specification version 1.0
   5  *
   6  * Copyright (C) 2005-2008 Intel Co.
   7  *      Fenghua Yu <fenghua.yu@intel.com>
   8  *      Bibo Mao <bibo.mao@intel.com>
   9  *      Chandramouli Narayanan <mouli@linux.intel.com>
  10  *      Huang Ying <ying.huang@intel.com>
  11  *
  12  * Code to convert EFI to E820 map has been implemented in elilo bootloader
  13  * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
  14  * is setup appropriately for EFI runtime code.
  15  * - mouli 06/14/2007.
  16  *
  17  */
  18
  19 #define pr_fmt(fmt) "efi: " fmt
  20
  21 #include <linux/kernel.h>
  22 #include <linux/init.h>
  23 #include <linux/mm.h>
  24 #include <linux/types.h>
  25 #include <linux/spinlock.h>
  26 #include <linux/memblock.h>
  27 #include <linux/ioport.h>
  28 #include <linux/mc146818rtc.h>
  29 #include <linux/efi.h>
  30 #include <linux/export.h>
  31 #include <linux/uaccess.h>
  32 #include <linux/io.h>
  33 #include <linux/reboot.h>
  34 #include <linux/slab.h>
  35 #include <linux/ucs2_string.h>
  36 #include <linux/mem_encrypt.h>
  37 #include <linux/sched/task.h>
  38
  39 #include <asm/setup.h>
  40 #include <asm/page.h>
  41 #include <asm/e820/api.h>
  42 #include <asm/pgtable.h>
  43 #include <asm/tlbflush.h>
  44 #include <asm/proto.h>
  45 #include <asm/efi.h>
  46 #include <asm/cacheflush.h>
  47 #include <asm/fixmap.h>
  48 #include <asm/realmode.h>
  49 #include <asm/time.h>
  50 #include <asm/pgalloc.h>
  51
  52 /*
  53  * We allocate runtime services regions top-down, starting from -4G, i.e.
  54  * 0xffff_ffff_0000_0000 and limit EFI VA mapping space to 64G.
  55  */
  56 static u64 efi_va = EFI_VA_START;
  57
  58 struct efi_scratch efi_scratch;
  59
  60 EXPORT_SYMBOL_GPL(efi_mm);
  61
  62 /*
  63  * We need our own copy of the higher levels of the page tables
  64  * because we want to avoid inserting EFI region mappings (EFI_VA_END
  65  * to EFI_VA_START) into the standard kernel page tables. Everything
  66  * else can be shared, see efi_sync_low_kernel_mappings().
  67  *
  68  * We don't want the pgd on the pgd_list and cannot use pgd_alloc() for the
  69  * allocation.
  70  */
  71 int __init efi_alloc_page_tables(void)
  72 {
  73         pgd_t *pgd, *efi_pgd;
  74         p4d_t *p4d;
  75         pud_t *pud;
  76         gfp_t gfp_mask;
  77
  78         if (efi_have_uv1_memmap())
  79                 return 0;
  80
  81         gfp_mask = GFP_KERNEL | __GFP_ZERO;
  82         efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER);
  83         if (!efi_pgd)
  84                 return -ENOMEM;
  85
  86         pgd = efi_pgd + pgd_index(EFI_VA_END);
  87         p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END);
  88         if (!p4d) {
  89                 free_page((unsigned long)efi_pgd);
  90                 return -ENOMEM;
  91         }
  92
  93         pud = pud_alloc(&init_mm, p4d, EFI_VA_END);
  94         if (!pud) {
  95                 if (pgtable_l5_enabled())
  96                         free_page((unsigned long) pgd_page_vaddr(*pgd));
  97                 free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER);
  98                 return -ENOMEM;
  99         }
 100
 101         efi_mm.pgd = efi_pgd;
 102         mm_init_cpumask(&efi_mm);
 103         init_new_context(NULL, &efi_mm);
 104
 105         return 0;
 106 }
 107
 108 /*
 109  * Add low kernel mappings for passing arguments to EFI functions.
 110  */
 111 void efi_sync_low_kernel_mappings(void)
 112 {
 113         unsigned num_entries;
 114         pgd_t *pgd_k, *pgd_efi;
 115         p4d_t *p4d_k, *p4d_efi;
 116         pud_t *pud_k, *pud_efi;
 117         pgd_t *efi_pgd = efi_mm.pgd;
 118
 119         if (efi_have_uv1_memmap())
 120                 return;
 121
 122         /*
 123          * We can share all PGD entries apart from the one entry that
 124          * covers the EFI runtime mapping space.
 125          *
 126          * Make sure the EFI runtime region mappings are guaranteed to
 127          * only span a single PGD entry and that the entry also maps
 128          * other important kernel regions.
 129          */
 130         MAYBE_BUILD_BUG_ON(pgd_index(EFI_VA_END) != pgd_index(MODULES_END));
 131         MAYBE_BUILD_BUG_ON((EFI_VA_START & PGDIR_MASK) !=
 132                         (EFI_VA_END & PGDIR_MASK));
 133
 134         pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET);
 135         pgd_k = pgd_offset_k(PAGE_OFFSET);
 136
 137         num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET);
 138         memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries);
 139
 140         /*
 141          * As with PGDs, we share all P4D entries apart from the one entry
 142          * that covers the EFI runtime mapping space.
 143          */
 144         BUILD_BUG_ON(p4d_index(EFI_VA_END) != p4d_index(MODULES_END));
 145         BUILD_BUG_ON((EFI_VA_START & P4D_MASK) != (EFI_VA_END & P4D_MASK));
 146
 147         pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
 148         pgd_k = pgd_offset_k(EFI_VA_END);
 149         p4d_efi = p4d_offset(pgd_efi, 0);
 150         p4d_k = p4d_offset(pgd_k, 0);
 151
 152         num_entries = p4d_index(EFI_VA_END);
 153         memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries);
 154
 155         /*
 156          * We share all the PUD entries apart from those that map the
 157          * EFI regions. Copy around them.
 158          */
 159         BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0);
 160         BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0);
 161
 162         p4d_efi = p4d_offset(pgd_efi, EFI_VA_END);
 163         p4d_k = p4d_offset(pgd_k, EFI_VA_END);
 164         pud_efi = pud_offset(p4d_efi, 0);
 165         pud_k = pud_offset(p4d_k, 0);
 166
 167         num_entries = pud_index(EFI_VA_END);
 168         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 169
 170         pud_efi = pud_offset(p4d_efi, EFI_VA_START);
 171         pud_k = pud_offset(p4d_k, EFI_VA_START);
 172
 173         num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START);
 174         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 175 }
 176
 177 /*
 178  * Wrapper for slow_virt_to_phys() that handles NULL addresses.
 179  */
 180 static inline phys_addr_t
 181 virt_to_phys_or_null_size(void *va, unsigned long size)
 182 {
 183         phys_addr_t pa;
 184
 185         if (!va)
 186                 return 0;
 187
 188         if (virt_addr_valid(va))
 189                 return virt_to_phys(va);
 190
 191         pa = slow_virt_to_phys(va);
 192
 193         /* check if the object crosses a page boundary */
 194         if (WARN_ON((pa ^ (pa + size - 1)) & PAGE_MASK))
 195                 return 0;
 196
 197         return pa;
 198 }
 199
 200 #define virt_to_phys_or_null(addr)                              \
 201         virt_to_phys_or_null_size((addr), sizeof(*(addr)))
 202
 203 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 204 {
 205         unsigned long pfn, text, pf, rodata;
 206         struct page *page;
 207         unsigned npages;
 208         pgd_t *pgd = efi_mm.pgd;
 209
 210         if (efi_have_uv1_memmap())
 211                 return 0;
 212
 213         /*
 214          * It can happen that the physical address of new_memmap lands in memory
 215          * which is not mapped in the EFI page table. Therefore we need to go
 216          * and ident-map those pages containing the map before calling
 217          * phys_efi_set_virtual_address_map().
 218          */
 219         pfn = pa_memmap >> PAGE_SHIFT;
 220         pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC;
 221         if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) {
 222                 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
 223                 return 1;
 224         }
 225
 226         /*
 227          * Certain firmware versions are way too sentimential and still believe
 228          * they are exclusive and unquestionable owners of the first physical page,
 229          * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
 230          * (but then write-access it later during SetVirtualAddressMap()).
 231          *
 232          * Create a 1:1 mapping for this page, to avoid triple faults during early
 233          * boot with such firmware. We are free to hand this page to the BIOS,
 234          * as trim_bios_range() will reserve the first page and isolate it away
 235          * from memory allocators anyway.
 236          */
 237         if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) {
 238                 pr_err("Failed to create 1:1 mapping for the first page!\n");
 239                 return 1;
 240         }
 241
 242         /*
 243          * When making calls to the firmware everything needs to be 1:1
 244          * mapped and addressable with 32-bit pointers. Map the kernel
 245          * text and allocate a new stack because we can't rely on the
 246          * stack pointer being < 4GB.
 247          */
 248         if (!efi_is_mixed())
 249                 return 0;
 250
 251         page = alloc_page(GFP_KERNEL|__GFP_DMA32);
 252         if (!page) {
 253                 pr_err("Unable to allocate EFI runtime stack < 4GB\n");
 254                 return 1;
 255         }
 256
 257         efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */
 258
 259         npages = (_etext - _text) >> PAGE_SHIFT;
 260         text = __pa(_text);
 261         pfn = text >> PAGE_SHIFT;
 262
 263         pf = _PAGE_ENC;
 264         if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, pf)) {
 265                 pr_err("Failed to map kernel text 1:1\n");
 266                 return 1;
 267         }
 268
 269         npages = (__end_rodata - __start_rodata) >> PAGE_SHIFT;
 270         rodata = __pa(__start_rodata);
 271         pfn = rodata >> PAGE_SHIFT;
 272         if (kernel_map_pages_in_pgd(pgd, pfn, rodata, npages, pf)) {
 273                 pr_err("Failed to map kernel rodata 1:1\n");
 274                 return 1;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static void __init __map_region(efi_memory_desc_t *md, u64 va)
 281 {
 282         unsigned long flags = _PAGE_RW;
 283         unsigned long pfn;
 284         pgd_t *pgd = efi_mm.pgd;
 285
 286         /*
 287          * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF
 288          * executable images in memory that consist of both R-X and
 289          * RW- sections, so we cannot apply read-only or non-exec
 290          * permissions just yet. However, modern EFI systems provide
 291          * a memory attributes table that describes those sections
 292          * with the appropriate restricted permissions, which are
 293          * applied in efi_runtime_update_mappings() below. All other
 294          * regions can be mapped non-executable at this point, with
 295          * the exception of boot services code regions, but those will
 296          * be unmapped again entirely in efi_free_boot_services().
 297          */
 298         if (md->type != EFI_BOOT_SERVICES_CODE &&
 299             md->type != EFI_RUNTIME_SERVICES_CODE)
 300                 flags |= _PAGE_NX;
 301
 302         if (!(md->attribute & EFI_MEMORY_WB))
 303                 flags |= _PAGE_PCD;
 304
 305         if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO)
 306                 flags |= _PAGE_ENC;
 307
 308         pfn = md->phys_addr >> PAGE_SHIFT;
 309         if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags))
 310                 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
 311                            md->phys_addr, va);
 312 }
 313
 314 void __init efi_map_region(efi_memory_desc_t *md)
 315 {
 316         unsigned long size = md->num_pages << PAGE_SHIFT;
 317         u64 pa = md->phys_addr;
 318
 319         if (efi_have_uv1_memmap())
 320                 return old_map_region(md);
 321
 322         /*
 323          * Make sure the 1:1 mappings are present as a catch-all for b0rked
 324          * firmware which doesn't update all internal pointers after switching
 325          * to virtual mode and would otherwise crap on us.
 326          */
 327         __map_region(md, md->phys_addr);
 328
 329         /*
 330          * Enforce the 1:1 mapping as the default virtual address when
 331          * booting in EFI mixed mode, because even though we may be
 332          * running a 64-bit kernel, the firmware may only be 32-bit.
 333          */
 334         if (efi_is_mixed()) {
 335                 md->virt_addr = md->phys_addr;
 336                 return;
 337         }
 338
 339         efi_va -= size;
 340
 341         /* Is PA 2M-aligned? */
 342         if (!(pa & (PMD_SIZE - 1))) {
 343                 efi_va &= PMD_MASK;
 344         } else {
 345                 u64 pa_offset = pa & (PMD_SIZE - 1);
 346                 u64 prev_va = efi_va;
 347
 348                 /* get us the same offset within this 2M page */
 349                 efi_va = (efi_va & PMD_MASK) + pa_offset;
 350
 351                 if (efi_va > prev_va)
 352                         efi_va -= PMD_SIZE;
 353         }
 354
 355         if (efi_va < EFI_VA_END) {
 356                 pr_warn(FW_WARN "VA address range overflow!\n");
 357                 return;
 358         }
 359
 360         /* Do the VA map */
 361         __map_region(md, efi_va);
 362         md->virt_addr = efi_va;
 363 }
 364
 365 /*
 366  * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
 367  * md->virt_addr is the original virtual address which had been mapped in kexec
 368  * 1st kernel.
 369  */
 370 void __init efi_map_region_fixed(efi_memory_desc_t *md)
 371 {
 372         __map_region(md, md->phys_addr);
 373         __map_region(md, md->virt_addr);
 374 }
 375
 376 void __init parse_efi_setup(u64 phys_addr, u32 data_len)
 377 {
 378         efi_setup = phys_addr + sizeof(struct setup_data);
 379 }
 380
 381 static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf)
 382 {
 383         unsigned long pfn;
 384         pgd_t *pgd = efi_mm.pgd;
 385         int err1, err2;
 386
 387         /* Update the 1:1 mapping */
 388         pfn = md->phys_addr >> PAGE_SHIFT;
 389         err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf);
 390         if (err1) {
 391                 pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n",
 392                            md->phys_addr, md->virt_addr);
 393         }
 394
 395         err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf);
 396         if (err2) {
 397                 pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n",
 398                            md->phys_addr, md->virt_addr);
 399         }
 400
 401         return err1 || err2;
 402 }
 403
 404 static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md)
 405 {
 406         unsigned long pf = 0;
 407
 408         if (md->attribute & EFI_MEMORY_XP)
 409                 pf |= _PAGE_NX;
 410
 411         if (!(md->attribute & EFI_MEMORY_RO))
 412                 pf |= _PAGE_RW;
 413
 414         if (sev_active())
 415                 pf |= _PAGE_ENC;
 416
 417         return efi_update_mappings(md, pf);
 418 }
 419
 420 void __init efi_runtime_update_mappings(void)
 421 {
 422         efi_memory_desc_t *md;
 423
 424         if (efi_have_uv1_memmap()) {
 425                 if (__supported_pte_mask & _PAGE_NX)
 426                         runtime_code_page_mkexec();
 427                 return;
 428         }
 429
 430         /*
 431          * Use the EFI Memory Attribute Table for mapping permissions if it
 432          * exists, since it is intended to supersede EFI_PROPERTIES_TABLE.
 433          */
 434         if (efi_enabled(EFI_MEM_ATTR)) {
 435                 efi_memattr_apply_permissions(NULL, efi_update_mem_attr);
 436                 return;
 437         }
 438
 439         /*
 440          * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace
 441          * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update
 442          * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not
 443          * published by the firmware. Even if we find a buggy implementation of
 444          * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to
 445          * EFI_PROPERTIES_TABLE, because of the same reason.
 446          */
 447
 448         if (!efi_enabled(EFI_NX_PE_DATA))
 449                 return;
 450
 451         for_each_efi_memory_desc(md) {
 452                 unsigned long pf = 0;
 453
 454                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
 455                         continue;
 456
 457                 if (!(md->attribute & EFI_MEMORY_WB))
 458                         pf |= _PAGE_PCD;
 459
 460                 if ((md->attribute & EFI_MEMORY_XP) ||
 461                         (md->type == EFI_RUNTIME_SERVICES_DATA))
 462                         pf |= _PAGE_NX;
 463
 464                 if (!(md->attribute & EFI_MEMORY_RO) &&
 465                         (md->type != EFI_RUNTIME_SERVICES_CODE))
 466                         pf |= _PAGE_RW;
 467
 468                 if (sev_active())
 469                         pf |= _PAGE_ENC;
 470
 471                 efi_update_mappings(md, pf);
 472         }
 473 }
 474
 475 void __init efi_dump_pagetable(void)
 476 {
 477 #ifdef CONFIG_EFI_PGT_DUMP
 478         if (efi_have_uv1_memmap())
 479                 ptdump_walk_pgd_level(NULL, &init_mm);
 480         else
 481                 ptdump_walk_pgd_level(NULL, &efi_mm);
 482 #endif
 483 }
 484
 485 /*
 486  * Makes the calling thread switch to/from efi_mm context. Can be used
 487  * in a kernel thread and user context. Preemption needs to remain disabled
 488  * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm
 489  * can not change under us.
 490  * It should be ensured that there are no concurent calls to this function.
 491  */
 492 void efi_switch_mm(struct mm_struct *mm)
 493 {
 494         efi_scratch.prev_mm = current->active_mm;
 495         current->active_mm = mm;
 496         switch_mm(efi_scratch.prev_mm, mm, NULL);
 497 }
 498
 499 static DEFINE_SPINLOCK(efi_runtime_lock);
 500
 501 /*
 502  * DS and ES contain user values.  We need to save them.
 503  * The 32-bit EFI code needs a valid DS, ES, and SS.  There's no
 504  * need to save the old SS: __KERNEL_DS is always acceptable.
 505  */
 506 #define __efi_thunk(func, ...)                                          \
 507 ({                                                                      \
 508         unsigned short __ds, __es;                                      \
 509         efi_status_t ____s;                                             \
 510                                                                         \
 511         savesegment(ds, __ds);                                          \
 512         savesegment(es, __es);                                          \
 513                                                                         \
 514         loadsegment(ss, __KERNEL_DS);                                   \
 515         loadsegment(ds, __KERNEL_DS);                                   \
 516         loadsegment(es, __KERNEL_DS);                                   \
 517                                                                         \
 518         ____s = efi64_thunk(efi.runtime->mixed_mode.func, __VA_ARGS__); \
 519                                                                         \
 520         loadsegment(ds, __ds);                                          \
 521         loadsegment(es, __es);                                          \
 522                                                                         \
 523         ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32;       \
 524         ____s;                                                          \
 525 })
 526
 527 /*
 528  * Switch to the EFI page tables early so that we can access the 1:1
 529  * runtime services mappings which are not mapped in any other page
 530  * tables.
 531  *
 532  * Also, disable interrupts because the IDT points to 64-bit handlers,
 533  * which aren't going to function correctly when we switch to 32-bit.
 534  */
 535 #define efi_thunk(func...)                                              \
 536 ({                                                                      \
 537         efi_status_t __s;                                               \
 538                                                                         \
 539         arch_efi_call_virt_setup();                                     \
 540                                                                         \
 541         __s = __efi_thunk(func);                                        \
 542                                                                         \
 543         arch_efi_call_virt_teardown();                                  \
 544                                                                         \
 545         __s;                                                            \
 546 })
 547
 548 static efi_status_t __init __no_sanitize_address
 549 efi_thunk_set_virtual_address_map(unsigned long memory_map_size,
 550                                   unsigned long descriptor_size,
 551                                   u32 descriptor_version,
 552                                   efi_memory_desc_t *virtual_map)
 553 {
 554         efi_status_t status;
 555         unsigned long flags;
 556
 557         efi_sync_low_kernel_mappings();
 558         local_irq_save(flags);
 559
 560         efi_switch_mm(&efi_mm);
 561
 562         status = __efi_thunk(set_virtual_address_map, memory_map_size,
 563                              descriptor_size, descriptor_version, virtual_map);
 564
 565         efi_switch_mm(efi_scratch.prev_mm);
 566         local_irq_restore(flags);
 567
 568         return status;
 569 }
 570
 571 static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 572 {
 573         return EFI_UNSUPPORTED;
 574 }
 575
 576 static efi_status_t efi_thunk_set_time(efi_time_t *tm)
 577 {
 578         return EFI_UNSUPPORTED;
 579 }
 580
 581 static efi_status_t
 582 efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
 583                           efi_time_t *tm)
 584 {
 585         return EFI_UNSUPPORTED;
 586 }
 587
 588 static efi_status_t
 589 efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 590 {
 591         return EFI_UNSUPPORTED;
 592 }
 593
 594 static unsigned long efi_name_size(efi_char16_t *name)
 595 {
 596         return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1;
 597 }
 598
 599 static efi_status_t
 600 efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
 601                        u32 *attr, unsigned long *data_size, void *data)
 602 {
 603         u8 buf[24] __aligned(8);
 604         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 605         efi_status_t status;
 606         u32 phys_name, phys_vendor, phys_attr;
 607         u32 phys_data_size, phys_data;
 608         unsigned long flags;
 609
 610         spin_lock_irqsave(&efi_runtime_lock, flags);
 611
 612         *vnd = *vendor;
 613
 614         phys_data_size = virt_to_phys_or_null(data_size);
 615         phys_vendor = virt_to_phys_or_null(vnd);
 616         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 617         phys_attr = virt_to_phys_or_null(attr);
 618         phys_data = virt_to_phys_or_null_size(data, *data_size);
 619
 620         if (!phys_name || (data && !phys_data))
 621                 status = EFI_INVALID_PARAMETER;
 622         else
 623                 status = efi_thunk(get_variable, phys_name, phys_vendor,
 624                                    phys_attr, phys_data_size, phys_data);
 625
 626         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 627
 628         return status;
 629 }
 630
 631 static efi_status_t
 632 efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
 633                        u32 attr, unsigned long data_size, void *data)
 634 {
 635         u8 buf[24] __aligned(8);
 636         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 637         u32 phys_name, phys_vendor, phys_data;
 638         efi_status_t status;
 639         unsigned long flags;
 640
 641         spin_lock_irqsave(&efi_runtime_lock, flags);
 642
 643         *vnd = *vendor;
 644
 645         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 646         phys_vendor = virt_to_phys_or_null(vnd);
 647         phys_data = virt_to_phys_or_null_size(data, data_size);
 648
 649         if (!phys_name || (data && !phys_data))
 650                 status = EFI_INVALID_PARAMETER;
 651         else
 652                 status = efi_thunk(set_variable, phys_name, phys_vendor,
 653                                    attr, data_size, phys_data);
 654
 655         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 656
 657         return status;
 658 }
 659
 660 static efi_status_t
 661 efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
 662                                    u32 attr, unsigned long data_size,
 663                                    void *data)
 664 {
 665         u8 buf[24] __aligned(8);
 666         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 667         u32 phys_name, phys_vendor, phys_data;
 668         efi_status_t status;
 669         unsigned long flags;
 670
 671         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
 672                 return EFI_NOT_READY;
 673
 674         *vnd = *vendor;
 675
 676         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 677         phys_vendor = virt_to_phys_or_null(vnd);
 678         phys_data = virt_to_phys_or_null_size(data, data_size);
 679
 680         if (!phys_name || (data && !phys_data))
 681                 status = EFI_INVALID_PARAMETER;
 682         else
 683                 status = efi_thunk(set_variable, phys_name, phys_vendor,
 684                                    attr, data_size, phys_data);
 685
 686         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 687
 688         return status;
 689 }
 690
 691 static efi_status_t
 692 efi_thunk_get_next_variable(unsigned long *name_size,
 693                             efi_char16_t *name,
 694                             efi_guid_t *vendor)
 695 {
 696         u8 buf[24] __aligned(8);
 697         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 698         efi_status_t status;
 699         u32 phys_name_size, phys_name, phys_vendor;
 700         unsigned long flags;
 701
 702         spin_lock_irqsave(&efi_runtime_lock, flags);
 703
 704         *vnd = *vendor;
 705
 706         phys_name_size = virt_to_phys_or_null(name_size);
 707         phys_vendor = virt_to_phys_or_null(vnd);
 708         phys_name = virt_to_phys_or_null_size(name, *name_size);
 709
 710         if (!phys_name)
 711                 status = EFI_INVALID_PARAMETER;
 712         else
 713                 status = efi_thunk(get_next_variable, phys_name_size,
 714                                    phys_name, phys_vendor);
 715
 716         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 717
 718         *vendor = *vnd;
 719         return status;
 720 }
 721
 722 static efi_status_t
 723 efi_thunk_get_next_high_mono_count(u32 *count)
 724 {
 725         return EFI_UNSUPPORTED;
 726 }
 727
 728 static void
 729 efi_thunk_reset_system(int reset_type, efi_status_t status,
 730                        unsigned long data_size, efi_char16_t *data)
 731 {
 732         u32 phys_data;
 733         unsigned long flags;
 734
 735         spin_lock_irqsave(&efi_runtime_lock, flags);
 736
 737         phys_data = virt_to_phys_or_null_size(data, data_size);
 738
 739         efi_thunk(reset_system, reset_type, status, data_size, phys_data);
 740
 741         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 742 }
 743
 744 static efi_status_t
 745 efi_thunk_update_capsule(efi_capsule_header_t **capsules,
 746                          unsigned long count, unsigned long sg_list)
 747 {
 748         /*
 749          * To properly support this function we would need to repackage
 750          * 'capsules' because the firmware doesn't understand 64-bit
 751          * pointers.
 752          */
 753         return EFI_UNSUPPORTED;
 754 }
 755
 756 static efi_status_t
 757 efi_thunk_query_variable_info(u32 attr, u64 *storage_space,
 758                               u64 *remaining_space,
 759                               u64 *max_variable_size)
 760 {
 761         efi_status_t status;
 762         u32 phys_storage, phys_remaining, phys_max;
 763         unsigned long flags;
 764
 765         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 766                 return EFI_UNSUPPORTED;
 767
 768         spin_lock_irqsave(&efi_runtime_lock, flags);
 769
 770         phys_storage = virt_to_phys_or_null(storage_space);
 771         phys_remaining = virt_to_phys_or_null(remaining_space);
 772         phys_max = virt_to_phys_or_null(max_variable_size);
 773
 774         status = efi_thunk(query_variable_info, attr, phys_storage,
 775                            phys_remaining, phys_max);
 776
 777         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 778
 779         return status;
 780 }
 781
 782 static efi_status_t
 783 efi_thunk_query_variable_info_nonblocking(u32 attr, u64 *storage_space,
 784                                           u64 *remaining_space,
 785                                           u64 *max_variable_size)
 786 {
 787         efi_status_t status;
 788         u32 phys_storage, phys_remaining, phys_max;
 789         unsigned long flags;
 790
 791         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 792                 return EFI_UNSUPPORTED;
 793
 794         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
 795                 return EFI_NOT_READY;
 796
 797         phys_storage = virt_to_phys_or_null(storage_space);
 798         phys_remaining = virt_to_phys_or_null(remaining_space);
 799         phys_max = virt_to_phys_or_null(max_variable_size);
 800
 801         status = efi_thunk(query_variable_info, attr, phys_storage,
 802                            phys_remaining, phys_max);
 803
 804         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 805
 806         return status;
 807 }
 808
 809 static efi_status_t
 810 efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
 811                              unsigned long count, u64 *max_size,
 812                              int *reset_type)
 813 {
 814         /*
 815          * To properly support this function we would need to repackage
 816          * 'capsules' because the firmware doesn't understand 64-bit
 817          * pointers.
 818          */
 819         return EFI_UNSUPPORTED;
 820 }
 821
 822 void __init efi_thunk_runtime_setup(void)
 823 {
 824         if (!IS_ENABLED(CONFIG_EFI_MIXED))
 825                 return;
 826
 827         efi.get_time = efi_thunk_get_time;
 828         efi.set_time = efi_thunk_set_time;
 829         efi.get_wakeup_time = efi_thunk_get_wakeup_time;
 830         efi.set_wakeup_time = efi_thunk_set_wakeup_time;
 831         efi.get_variable = efi_thunk_get_variable;
 832         efi.get_next_variable = efi_thunk_get_next_variable;
 833         efi.set_variable = efi_thunk_set_variable;
 834         efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking;
 835         efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count;
 836         efi.reset_system = efi_thunk_reset_system;
 837         efi.query_variable_info = efi_thunk_query_variable_info;
 838         efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking;
 839         efi.update_capsule = efi_thunk_update_capsule;
 840         efi.query_capsule_caps = efi_thunk_query_capsule_caps;
 841 }
 842
 843 efi_status_t __init __no_sanitize_address
 844 efi_set_virtual_address_map(unsigned long memory_map_size,
 845                             unsigned long descriptor_size,
 846                             u32 descriptor_version,
 847                             efi_memory_desc_t *virtual_map,
 848                             unsigned long systab_phys)
 849 {
 850         const efi_system_table_t *systab = (efi_system_table_t *)systab_phys;
 851         efi_status_t status;
 852         unsigned long flags;
 853         pgd_t *save_pgd = NULL;
 854
 855         if (efi_is_mixed())
 856                 return efi_thunk_set_virtual_address_map(memory_map_size,
 857                                                          descriptor_size,
 858                                                          descriptor_version,
 859                                                          virtual_map);
 860
 861         if (efi_have_uv1_memmap()) {
 862                 save_pgd = efi_uv1_memmap_phys_prolog();
 863                 if (!save_pgd)
 864                         return EFI_ABORTED;
 865         } else {
 866                 efi_switch_mm(&efi_mm);
 867         }
 868
 869         kernel_fpu_begin();
 870
 871         /* Disable interrupts around EFI calls: */
 872         local_irq_save(flags);
 873         status = efi_call(efi.runtime->set_virtual_address_map,
 874                           memory_map_size, descriptor_size,
 875                           descriptor_version, virtual_map);
 876         local_irq_restore(flags);
 877
 878         kernel_fpu_end();
 879
 880         /* grab the virtually remapped EFI runtime services table pointer */
 881         efi.runtime = READ_ONCE(systab->runtime);
 882
 883         if (save_pgd)
 884                 efi_uv1_memmap_phys_epilog(save_pgd);
 885         else
 886                 efi_switch_mm(efi_scratch.prev_mm);
 887
 888         return status;
 889 }