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