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 #include <asm/sev-es.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 static struct mm_struct *efi_prev_mm;
  58
  59 /*
  60  * We need our own copy of the higher levels of the page tables
  61  * because we want to avoid inserting EFI region mappings (EFI_VA_END
  62  * to EFI_VA_START) into the standard kernel page tables. Everything
  63  * else can be shared, see efi_sync_low_kernel_mappings().
  64  *
  65  * We don't want the pgd on the pgd_list and cannot use pgd_alloc() for the
  66  * allocation.
  67  */
  68 int __init efi_alloc_page_tables(void)
  69 {
  70         pgd_t *pgd, *efi_pgd;
  71         p4d_t *p4d;
  72         pud_t *pud;
  73         gfp_t gfp_mask;
  74
  75         gfp_mask = GFP_KERNEL | __GFP_ZERO;
  76         efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER);
  77         if (!efi_pgd)
  78                 goto fail;
  79
  80         pgd = efi_pgd + pgd_index(EFI_VA_END);
  81         p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END);
  82         if (!p4d)
  83                 goto free_pgd;
  84
  85         pud = pud_alloc(&init_mm, p4d, EFI_VA_END);
  86         if (!pud)
  87                 goto free_p4d;
  88
  89         efi_mm.pgd = efi_pgd;
  90         mm_init_cpumask(&efi_mm);
  91         init_new_context(NULL, &efi_mm);
  92
  93         return 0;
  94
  95 free_p4d:
  96         if (pgtable_l5_enabled())
  97                 free_page((unsigned long)pgd_page_vaddr(*pgd));
  98 free_pgd:
  99         free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER);
 100 fail:
 101         return -ENOMEM;
 102 }
 103
 104 /*
 105  * Add low kernel mappings for passing arguments to EFI functions.
 106  */
 107 void efi_sync_low_kernel_mappings(void)
 108 {
 109         unsigned num_entries;
 110         pgd_t *pgd_k, *pgd_efi;
 111         p4d_t *p4d_k, *p4d_efi;
 112         pud_t *pud_k, *pud_efi;
 113         pgd_t *efi_pgd = efi_mm.pgd;
 114
 115         /*
 116          * We can share all PGD entries apart from the one entry that
 117          * covers the EFI runtime mapping space.
 118          *
 119          * Make sure the EFI runtime region mappings are guaranteed to
 120          * only span a single PGD entry and that the entry also maps
 121          * other important kernel regions.
 122          */
 123         MAYBE_BUILD_BUG_ON(pgd_index(EFI_VA_END) != pgd_index(MODULES_END));
 124         MAYBE_BUILD_BUG_ON((EFI_VA_START & PGDIR_MASK) !=
 125                         (EFI_VA_END & PGDIR_MASK));
 126
 127         pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET);
 128         pgd_k = pgd_offset_k(PAGE_OFFSET);
 129
 130         num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET);
 131         memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries);
 132
 133         /*
 134          * As with PGDs, we share all P4D entries apart from the one entry
 135          * that covers the EFI runtime mapping space.
 136          */
 137         BUILD_BUG_ON(p4d_index(EFI_VA_END) != p4d_index(MODULES_END));
 138         BUILD_BUG_ON((EFI_VA_START & P4D_MASK) != (EFI_VA_END & P4D_MASK));
 139
 140         pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
 141         pgd_k = pgd_offset_k(EFI_VA_END);
 142         p4d_efi = p4d_offset(pgd_efi, 0);
 143         p4d_k = p4d_offset(pgd_k, 0);
 144
 145         num_entries = p4d_index(EFI_VA_END);
 146         memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries);
 147
 148         /*
 149          * We share all the PUD entries apart from those that map the
 150          * EFI regions. Copy around them.
 151          */
 152         BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0);
 153         BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0);
 154
 155         p4d_efi = p4d_offset(pgd_efi, EFI_VA_END);
 156         p4d_k = p4d_offset(pgd_k, EFI_VA_END);
 157         pud_efi = pud_offset(p4d_efi, 0);
 158         pud_k = pud_offset(p4d_k, 0);
 159
 160         num_entries = pud_index(EFI_VA_END);
 161         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 162
 163         pud_efi = pud_offset(p4d_efi, EFI_VA_START);
 164         pud_k = pud_offset(p4d_k, EFI_VA_START);
 165
 166         num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START);
 167         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
 168 }
 169
 170 /*
 171  * Wrapper for slow_virt_to_phys() that handles NULL addresses.
 172  */
 173 static inline phys_addr_t
 174 virt_to_phys_or_null_size(void *va, unsigned long size)
 175 {
 176         phys_addr_t pa;
 177
 178         if (!va)
 179                 return 0;
 180
 181         if (virt_addr_valid(va))
 182                 return virt_to_phys(va);
 183
 184         pa = slow_virt_to_phys(va);
 185
 186         /* check if the object crosses a page boundary */
 187         if (WARN_ON((pa ^ (pa + size - 1)) & PAGE_MASK))
 188                 return 0;
 189
 190         return pa;
 191 }
 192
 193 #define virt_to_phys_or_null(addr)                              \
 194         virt_to_phys_or_null_size((addr), sizeof(*(addr)))
 195
 196 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
 197 {
 198         unsigned long pfn, text, pf, rodata;
 199         struct page *page;
 200         unsigned npages;
 201         pgd_t *pgd = efi_mm.pgd;
 202
 203         /*
 204          * It can happen that the physical address of new_memmap lands in memory
 205          * which is not mapped in the EFI page table. Therefore we need to go
 206          * and ident-map those pages containing the map before calling
 207          * phys_efi_set_virtual_address_map().
 208          */
 209         pfn = pa_memmap >> PAGE_SHIFT;
 210         pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC;
 211         if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) {
 212                 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
 213                 return 1;
 214         }
 215
 216         /*
 217          * Certain firmware versions are way too sentimential and still believe
 218          * they are exclusive and unquestionable owners of the first physical page,
 219          * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
 220          * (but then write-access it later during SetVirtualAddressMap()).
 221          *
 222          * Create a 1:1 mapping for this page, to avoid triple faults during early
 223          * boot with such firmware. We are free to hand this page to the BIOS,
 224          * as trim_bios_range() will reserve the first page and isolate it away
 225          * from memory allocators anyway.
 226          */
 227         if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) {
 228                 pr_err("Failed to create 1:1 mapping for the first page!\n");
 229                 return 1;
 230         }
 231
 232         /*
 233          * When SEV-ES is active, the GHCB as set by the kernel will be used
 234          * by firmware. Create a 1:1 unencrypted mapping for each GHCB.
 235          */
 236         if (sev_es_efi_map_ghcbs(pgd)) {
 237                 pr_err("Failed to create 1:1 mapping for the GHCBs!\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_mixed_mode_stack_pa = 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
 272         pf = _PAGE_NX | _PAGE_ENC;
 273         if (kernel_map_pages_in_pgd(pgd, pfn, rodata, npages, pf)) {
 274                 pr_err("Failed to map kernel rodata 1:1\n");
 275                 return 1;
 276         }
 277
 278         return 0;
 279 }
 280
 281 static void __init __map_region(efi_memory_desc_t *md, u64 va)
 282 {
 283         unsigned long flags = _PAGE_RW;
 284         unsigned long pfn;
 285         pgd_t *pgd = efi_mm.pgd;
 286
 287         /*
 288          * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF
 289          * executable images in memory that consist of both R-X and
 290          * RW- sections, so we cannot apply read-only or non-exec
 291          * permissions just yet. However, modern EFI systems provide
 292          * a memory attributes table that describes those sections
 293          * with the appropriate restricted permissions, which are
 294          * applied in efi_runtime_update_mappings() below. All other
 295          * regions can be mapped non-executable at this point, with
 296          * the exception of boot services code regions, but those will
 297          * be unmapped again entirely in efi_free_boot_services().
 298          */
 299         if (md->type != EFI_BOOT_SERVICES_CODE &&
 300             md->type != EFI_RUNTIME_SERVICES_CODE)
 301                 flags |= _PAGE_NX;
 302
 303         if (!(md->attribute & EFI_MEMORY_WB))
 304                 flags |= _PAGE_PCD;
 305
 306         if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO)
 307                 flags |= _PAGE_ENC;
 308
 309         pfn = md->phys_addr >> PAGE_SHIFT;
 310         if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags))
 311                 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
 312                            md->phys_addr, va);
 313 }
 314
 315 void __init efi_map_region(efi_memory_desc_t *md)
 316 {
 317         unsigned long size = md->num_pages << PAGE_SHIFT;
 318         u64 pa = md->phys_addr;
 319
 320         /*
 321          * Make sure the 1:1 mappings are present as a catch-all for b0rked
 322          * firmware which doesn't update all internal pointers after switching
 323          * to virtual mode and would otherwise crap on us.
 324          */
 325         __map_region(md, md->phys_addr);
 326
 327         /*
 328          * Enforce the 1:1 mapping as the default virtual address when
 329          * booting in EFI mixed mode, because even though we may be
 330          * running a 64-bit kernel, the firmware may only be 32-bit.
 331          */
 332         if (efi_is_mixed()) {
 333                 md->virt_addr = md->phys_addr;
 334                 return;
 335         }
 336
 337         efi_va -= size;
 338
 339         /* Is PA 2M-aligned? */
 340         if (!(pa & (PMD_SIZE - 1))) {
 341                 efi_va &= PMD_MASK;
 342         } else {
 343                 u64 pa_offset = pa & (PMD_SIZE - 1);
 344                 u64 prev_va = efi_va;
 345
 346                 /* get us the same offset within this 2M page */
 347                 efi_va = (efi_va & PMD_MASK) + pa_offset;
 348
 349                 if (efi_va > prev_va)
 350                         efi_va -= PMD_SIZE;
 351         }
 352
 353         if (efi_va < EFI_VA_END) {
 354                 pr_warn(FW_WARN "VA address range overflow!\n");
 355                 return;
 356         }
 357
 358         /* Do the VA map */
 359         __map_region(md, efi_va);
 360         md->virt_addr = efi_va;
 361 }
 362
 363 /*
 364  * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
 365  * md->virt_addr is the original virtual address which had been mapped in kexec
 366  * 1st kernel.
 367  */
 368 void __init efi_map_region_fixed(efi_memory_desc_t *md)
 369 {
 370         __map_region(md, md->phys_addr);
 371         __map_region(md, md->virt_addr);
 372 }
 373
 374 void __init parse_efi_setup(u64 phys_addr, u32 data_len)
 375 {
 376         efi_setup = phys_addr + sizeof(struct setup_data);
 377 }
 378
 379 static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf)
 380 {
 381         unsigned long pfn;
 382         pgd_t *pgd = efi_mm.pgd;
 383         int err1, err2;
 384
 385         /* Update the 1:1 mapping */
 386         pfn = md->phys_addr >> PAGE_SHIFT;
 387         err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf);
 388         if (err1) {
 389                 pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n",
 390                            md->phys_addr, md->virt_addr);
 391         }
 392
 393         err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf);
 394         if (err2) {
 395                 pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n",
 396                            md->phys_addr, md->virt_addr);
 397         }
 398
 399         return err1 || err2;
 400 }
 401
 402 static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md)
 403 {
 404         unsigned long pf = 0;
 405
 406         if (md->attribute & EFI_MEMORY_XP)
 407                 pf |= _PAGE_NX;
 408
 409         if (!(md->attribute & EFI_MEMORY_RO))
 410                 pf |= _PAGE_RW;
 411
 412         if (sev_active())
 413                 pf |= _PAGE_ENC;
 414
 415         return efi_update_mappings(md, pf);
 416 }
 417
 418 void __init efi_runtime_update_mappings(void)
 419 {
 420         efi_memory_desc_t *md;
 421
 422         /*
 423          * Use the EFI Memory Attribute Table for mapping permissions if it
 424          * exists, since it is intended to supersede EFI_PROPERTIES_TABLE.
 425          */
 426         if (efi_enabled(EFI_MEM_ATTR)) {
 427                 efi_memattr_apply_permissions(NULL, efi_update_mem_attr);
 428                 return;
 429         }
 430
 431         /*
 432          * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace
 433          * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update
 434          * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not
 435          * published by the firmware. Even if we find a buggy implementation of
 436          * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to
 437          * EFI_PROPERTIES_TABLE, because of the same reason.
 438          */
 439
 440         if (!efi_enabled(EFI_NX_PE_DATA))
 441                 return;
 442
 443         for_each_efi_memory_desc(md) {
 444                 unsigned long pf = 0;
 445
 446                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
 447                         continue;
 448
 449                 if (!(md->attribute & EFI_MEMORY_WB))
 450                         pf |= _PAGE_PCD;
 451
 452                 if ((md->attribute & EFI_MEMORY_XP) ||
 453                         (md->type == EFI_RUNTIME_SERVICES_DATA))
 454                         pf |= _PAGE_NX;
 455
 456                 if (!(md->attribute & EFI_MEMORY_RO) &&
 457                         (md->type != EFI_RUNTIME_SERVICES_CODE))
 458                         pf |= _PAGE_RW;
 459
 460                 if (sev_active())
 461                         pf |= _PAGE_ENC;
 462
 463                 efi_update_mappings(md, pf);
 464         }
 465 }
 466
 467 void __init efi_dump_pagetable(void)
 468 {
 469 #ifdef CONFIG_EFI_PGT_DUMP
 470         ptdump_walk_pgd_level(NULL, &efi_mm);
 471 #endif
 472 }
 473
 474 /*
 475  * Makes the calling thread switch to/from efi_mm context. Can be used
 476  * in a kernel thread and user context. Preemption needs to remain disabled
 477  * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm
 478  * can not change under us.
 479  * It should be ensured that there are no concurent calls to this function.
 480  */
 481 void efi_enter_mm(void)
 482 {
 483         efi_prev_mm = current->active_mm;
 484         current->active_mm = &efi_mm;
 485         switch_mm(efi_prev_mm, &efi_mm, NULL);
 486 }
 487
 488 void efi_leave_mm(void)
 489 {
 490         current->active_mm = efi_prev_mm;
 491         switch_mm(&efi_mm, efi_prev_mm, NULL);
 492 }
 493
 494 static DEFINE_SPINLOCK(efi_runtime_lock);
 495
 496 /*
 497  * DS and ES contain user values.  We need to save them.
 498  * The 32-bit EFI code needs a valid DS, ES, and SS.  There's no
 499  * need to save the old SS: __KERNEL_DS is always acceptable.
 500  */
 501 #define __efi_thunk(func, ...)                                          \
 502 ({                                                                      \
 503         unsigned short __ds, __es;                                      \
 504         efi_status_t ____s;                                             \
 505                                                                         \
 506         savesegment(ds, __ds);                                          \
 507         savesegment(es, __es);                                          \
 508                                                                         \
 509         loadsegment(ss, __KERNEL_DS);                                   \
 510         loadsegment(ds, __KERNEL_DS);                                   \
 511         loadsegment(es, __KERNEL_DS);                                   \
 512                                                                         \
 513         ____s = efi64_thunk(efi.runtime->mixed_mode.func, __VA_ARGS__); \
 514                                                                         \
 515         loadsegment(ds, __ds);                                          \
 516         loadsegment(es, __es);                                          \
 517                                                                         \
 518         ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32;       \
 519         ____s;                                                          \
 520 })
 521
 522 /*
 523  * Switch to the EFI page tables early so that we can access the 1:1
 524  * runtime services mappings which are not mapped in any other page
 525  * tables.
 526  *
 527  * Also, disable interrupts because the IDT points to 64-bit handlers,
 528  * which aren't going to function correctly when we switch to 32-bit.
 529  */
 530 #define efi_thunk(func...)                                              \
 531 ({                                                                      \
 532         efi_status_t __s;                                               \
 533                                                                         \
 534         arch_efi_call_virt_setup();                                     \
 535                                                                         \
 536         __s = __efi_thunk(func);                                        \
 537                                                                         \
 538         arch_efi_call_virt_teardown();                                  \
 539                                                                         \
 540         __s;                                                            \
 541 })
 542
 543 static efi_status_t __init __no_sanitize_address
 544 efi_thunk_set_virtual_address_map(unsigned long memory_map_size,
 545                                   unsigned long descriptor_size,
 546                                   u32 descriptor_version,
 547                                   efi_memory_desc_t *virtual_map)
 548 {
 549         efi_status_t status;
 550         unsigned long flags;
 551
 552         efi_sync_low_kernel_mappings();
 553         local_irq_save(flags);
 554
 555         efi_enter_mm();
 556
 557         status = __efi_thunk(set_virtual_address_map, memory_map_size,
 558                              descriptor_size, descriptor_version, virtual_map);
 559
 560         efi_leave_mm();
 561         local_irq_restore(flags);
 562
 563         return status;
 564 }
 565
 566 static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
 567 {
 568         return EFI_UNSUPPORTED;
 569 }
 570
 571 static efi_status_t efi_thunk_set_time(efi_time_t *tm)
 572 {
 573         return EFI_UNSUPPORTED;
 574 }
 575
 576 static efi_status_t
 577 efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
 578                           efi_time_t *tm)
 579 {
 580         return EFI_UNSUPPORTED;
 581 }
 582
 583 static efi_status_t
 584 efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
 585 {
 586         return EFI_UNSUPPORTED;
 587 }
 588
 589 static unsigned long efi_name_size(efi_char16_t *name)
 590 {
 591         return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1;
 592 }
 593
 594 static efi_status_t
 595 efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
 596                        u32 *attr, unsigned long *data_size, void *data)
 597 {
 598         u8 buf[24] __aligned(8);
 599         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 600         efi_status_t status;
 601         u32 phys_name, phys_vendor, phys_attr;
 602         u32 phys_data_size, phys_data;
 603         unsigned long flags;
 604
 605         spin_lock_irqsave(&efi_runtime_lock, flags);
 606
 607         *vnd = *vendor;
 608
 609         phys_data_size = virt_to_phys_or_null(data_size);
 610         phys_vendor = virt_to_phys_or_null(vnd);
 611         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 612         phys_attr = virt_to_phys_or_null(attr);
 613         phys_data = virt_to_phys_or_null_size(data, *data_size);
 614
 615         if (!phys_name || (data && !phys_data))
 616                 status = EFI_INVALID_PARAMETER;
 617         else
 618                 status = efi_thunk(get_variable, phys_name, phys_vendor,
 619                                    phys_attr, phys_data_size, phys_data);
 620
 621         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 622
 623         return status;
 624 }
 625
 626 static efi_status_t
 627 efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
 628                        u32 attr, unsigned long data_size, void *data)
 629 {
 630         u8 buf[24] __aligned(8);
 631         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 632         u32 phys_name, phys_vendor, phys_data;
 633         efi_status_t status;
 634         unsigned long flags;
 635
 636         spin_lock_irqsave(&efi_runtime_lock, flags);
 637
 638         *vnd = *vendor;
 639
 640         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 641         phys_vendor = virt_to_phys_or_null(vnd);
 642         phys_data = virt_to_phys_or_null_size(data, data_size);
 643
 644         if (!phys_name || (data && !phys_data))
 645                 status = EFI_INVALID_PARAMETER;
 646         else
 647                 status = efi_thunk(set_variable, phys_name, phys_vendor,
 648                                    attr, data_size, phys_data);
 649
 650         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 651
 652         return status;
 653 }
 654
 655 static efi_status_t
 656 efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
 657                                    u32 attr, unsigned long data_size,
 658                                    void *data)
 659 {
 660         u8 buf[24] __aligned(8);
 661         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 662         u32 phys_name, phys_vendor, phys_data;
 663         efi_status_t status;
 664         unsigned long flags;
 665
 666         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
 667                 return EFI_NOT_READY;
 668
 669         *vnd = *vendor;
 670
 671         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
 672         phys_vendor = virt_to_phys_or_null(vnd);
 673         phys_data = virt_to_phys_or_null_size(data, data_size);
 674
 675         if (!phys_name || (data && !phys_data))
 676                 status = EFI_INVALID_PARAMETER;
 677         else
 678                 status = efi_thunk(set_variable, phys_name, phys_vendor,
 679                                    attr, data_size, phys_data);
 680
 681         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 682
 683         return status;
 684 }
 685
 686 static efi_status_t
 687 efi_thunk_get_next_variable(unsigned long *name_size,
 688                             efi_char16_t *name,
 689                             efi_guid_t *vendor)
 690 {
 691         u8 buf[24] __aligned(8);
 692         efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd));
 693         efi_status_t status;
 694         u32 phys_name_size, phys_name, phys_vendor;
 695         unsigned long flags;
 696
 697         spin_lock_irqsave(&efi_runtime_lock, flags);
 698
 699         *vnd = *vendor;
 700
 701         phys_name_size = virt_to_phys_or_null(name_size);
 702         phys_vendor = virt_to_phys_or_null(vnd);
 703         phys_name = virt_to_phys_or_null_size(name, *name_size);
 704
 705         if (!phys_name)
 706                 status = EFI_INVALID_PARAMETER;
 707         else
 708                 status = efi_thunk(get_next_variable, phys_name_size,
 709                                    phys_name, phys_vendor);
 710
 711         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 712
 713         *vendor = *vnd;
 714         return status;
 715 }
 716
 717 static efi_status_t
 718 efi_thunk_get_next_high_mono_count(u32 *count)
 719 {
 720         return EFI_UNSUPPORTED;
 721 }
 722
 723 static void
 724 efi_thunk_reset_system(int reset_type, efi_status_t status,
 725                        unsigned long data_size, efi_char16_t *data)
 726 {
 727         u32 phys_data;
 728         unsigned long flags;
 729
 730         spin_lock_irqsave(&efi_runtime_lock, flags);
 731
 732         phys_data = virt_to_phys_or_null_size(data, data_size);
 733
 734         efi_thunk(reset_system, reset_type, status, data_size, phys_data);
 735
 736         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 737 }
 738
 739 static efi_status_t
 740 efi_thunk_update_capsule(efi_capsule_header_t **capsules,
 741                          unsigned long count, unsigned long sg_list)
 742 {
 743         /*
 744          * To properly support this function we would need to repackage
 745          * 'capsules' because the firmware doesn't understand 64-bit
 746          * pointers.
 747          */
 748         return EFI_UNSUPPORTED;
 749 }
 750
 751 static efi_status_t
 752 efi_thunk_query_variable_info(u32 attr, u64 *storage_space,
 753                               u64 *remaining_space,
 754                               u64 *max_variable_size)
 755 {
 756         efi_status_t status;
 757         u32 phys_storage, phys_remaining, phys_max;
 758         unsigned long flags;
 759
 760         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 761                 return EFI_UNSUPPORTED;
 762
 763         spin_lock_irqsave(&efi_runtime_lock, flags);
 764
 765         phys_storage = virt_to_phys_or_null(storage_space);
 766         phys_remaining = virt_to_phys_or_null(remaining_space);
 767         phys_max = virt_to_phys_or_null(max_variable_size);
 768
 769         status = efi_thunk(query_variable_info, attr, phys_storage,
 770                            phys_remaining, phys_max);
 771
 772         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 773
 774         return status;
 775 }
 776
 777 static efi_status_t
 778 efi_thunk_query_variable_info_nonblocking(u32 attr, u64 *storage_space,
 779                                           u64 *remaining_space,
 780                                           u64 *max_variable_size)
 781 {
 782         efi_status_t status;
 783         u32 phys_storage, phys_remaining, phys_max;
 784         unsigned long flags;
 785
 786         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
 787                 return EFI_UNSUPPORTED;
 788
 789         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
 790                 return EFI_NOT_READY;
 791
 792         phys_storage = virt_to_phys_or_null(storage_space);
 793         phys_remaining = virt_to_phys_or_null(remaining_space);
 794         phys_max = virt_to_phys_or_null(max_variable_size);
 795
 796         status = efi_thunk(query_variable_info, attr, phys_storage,
 797                            phys_remaining, phys_max);
 798
 799         spin_unlock_irqrestore(&efi_runtime_lock, flags);
 800
 801         return status;
 802 }
 803
 804 static efi_status_t
 805 efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
 806                              unsigned long count, u64 *max_size,
 807                              int *reset_type)
 808 {
 809         /*
 810          * To properly support this function we would need to repackage
 811          * 'capsules' because the firmware doesn't understand 64-bit
 812          * pointers.
 813          */
 814         return EFI_UNSUPPORTED;
 815 }
 816
 817 void __init efi_thunk_runtime_setup(void)
 818 {
 819         if (!IS_ENABLED(CONFIG_EFI_MIXED))
 820                 return;
 821
 822         efi.get_time = efi_thunk_get_time;
 823         efi.set_time = efi_thunk_set_time;
 824         efi.get_wakeup_time = efi_thunk_get_wakeup_time;
 825         efi.set_wakeup_time = efi_thunk_set_wakeup_time;
 826         efi.get_variable = efi_thunk_get_variable;
 827         efi.get_next_variable = efi_thunk_get_next_variable;
 828         efi.set_variable = efi_thunk_set_variable;
 829         efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking;
 830         efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count;
 831         efi.reset_system = efi_thunk_reset_system;
 832         efi.query_variable_info = efi_thunk_query_variable_info;
 833         efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking;
 834         efi.update_capsule = efi_thunk_update_capsule;
 835         efi.query_capsule_caps = efi_thunk_query_capsule_caps;
 836 }
 837
 838 efi_status_t __init __no_sanitize_address
 839 efi_set_virtual_address_map(unsigned long memory_map_size,
 840                             unsigned long descriptor_size,
 841                             u32 descriptor_version,
 842                             efi_memory_desc_t *virtual_map,
 843                             unsigned long systab_phys)
 844 {
 845         const efi_system_table_t *systab = (efi_system_table_t *)systab_phys;
 846         efi_status_t status;
 847         unsigned long flags;
 848
 849         if (efi_is_mixed())
 850                 return efi_thunk_set_virtual_address_map(memory_map_size,
 851                                                          descriptor_size,
 852                                                          descriptor_version,
 853                                                          virtual_map);
 854         efi_enter_mm();
 855
 856         kernel_fpu_begin();
 857
 858         /* Disable interrupts around EFI calls: */
 859         local_irq_save(flags);
 860         status = efi_call(efi.runtime->set_virtual_address_map,
 861                           memory_map_size, descriptor_size,
 862                           descriptor_version, virtual_map);
 863         local_irq_restore(flags);
 864
 865         kernel_fpu_end();
 866
 867         /* grab the virtually remapped EFI runtime services table pointer */
 868         efi.runtime = READ_ONCE(systab->runtime);
 869
 870         efi_leave_mm();
 871
 872         return status;
 873 }