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