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 */ 56static u64 efi_va = EFI_VA_START; 57 58struct efi_scratch efi_scratch; 59 60EXPORT_SYMBOL_GPL(efi_mm); 61 62/* 63 * We need our own copy of the higher levels of the page tables 64 * because we want to avoid inserting EFI region mappings (EFI_VA_END 65 * to EFI_VA_START) into the standard kernel page tables. Everything 66 * else can be shared, see efi_sync_low_kernel_mappings(). 67 * 68 * We don't want the pgd on the pgd_list and cannot use pgd_alloc() for the 69 * allocation. 70 */ 71int __init efi_alloc_page_tables(void) 72{ 73 pgd_t *pgd, *efi_pgd; 74 p4d_t *p4d; 75 pud_t *pud; 76 gfp_t gfp_mask; 77 78 gfp_mask = GFP_KERNEL | __GFP_ZERO; 79 efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER); 80 if (!efi_pgd) 81 goto fail; 82 83 pgd = efi_pgd + pgd_index(EFI_VA_END); 84 p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END); 85 if (!p4d) 86 goto free_pgd; 87 88 pud = pud_alloc(&init_mm, p4d, EFI_VA_END); 89 if (!pud) 90 goto free_p4d; 91 92 efi_mm.pgd = efi_pgd; 93 mm_init_cpumask(&efi_mm); 94 init_new_context(NULL, &efi_mm); 95 96 return 0; 97 98free_p4d: 99 if (pgtable_l5_enabled()) 100 free_page((unsigned long)pgd_page_vaddr(*pgd)); 101free_pgd: 102 free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER); 103fail: 104 return -ENOMEM; 105} 106 107/* 108 * Add low kernel mappings for passing arguments to EFI functions. 109 */ 110void 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 pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET); 119 pgd_k = pgd_offset_k(PAGE_OFFSET); 120 121 num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET); 122 memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries); 123 124 pgd_efi = efi_pgd + pgd_index(EFI_VA_END); 125 pgd_k = pgd_offset_k(EFI_VA_END); 126 p4d_efi = p4d_offset(pgd_efi, 0); 127 p4d_k = p4d_offset(pgd_k, 0); 128 129 num_entries = p4d_index(EFI_VA_END); 130 memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries); 131 132 /* 133 * We share all the PUD entries apart from those that map the 134 * EFI regions. Copy around them. 135 */ 136 BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0); 137 BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0); 138 139 p4d_efi = p4d_offset(pgd_efi, EFI_VA_END); 140 p4d_k = p4d_offset(pgd_k, EFI_VA_END); 141 pud_efi = pud_offset(p4d_efi, 0); 142 pud_k = pud_offset(p4d_k, 0); 143 144 num_entries = pud_index(EFI_VA_END); 145 memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries); 146 147 pud_efi = pud_offset(p4d_efi, EFI_VA_START); 148 pud_k = pud_offset(p4d_k, EFI_VA_START); 149 150 num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START); 151 memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries); 152} 153 154/* 155 * Wrapper for slow_virt_to_phys() that handles NULL addresses. 156 */ 157static inline phys_addr_t 158virt_to_phys_or_null_size(void *va, unsigned long size) 159{ 160 phys_addr_t pa; 161 162 if (!va) 163 return 0; 164 165 if (virt_addr_valid(va)) 166 return virt_to_phys(va); 167 168 pa = slow_virt_to_phys(va); 169 170 /* check if the object crosses a page boundary */ 171 if (WARN_ON((pa ^ (pa + size - 1)) & PAGE_MASK)) 172 return 0; 173 174 return pa; 175} 176 177#define virt_to_phys_or_null(addr) \ 178 virt_to_phys_or_null_size((addr), sizeof(*(addr))) 179 180int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) 181{ 182 unsigned long pfn, text, pf, rodata; 183 struct page *page; 184 unsigned npages; 185 pgd_t *pgd = efi_mm.pgd; 186 187 /* 188 * It can happen that the physical address of new_memmap lands in memory 189 * which is not mapped in the EFI page table. Therefore we need to go 190 * and ident-map those pages containing the map before calling 191 * phys_efi_set_virtual_address_map(). 192 */ 193 pfn = pa_memmap >> PAGE_SHIFT; 194 pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC; 195 if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) { 196 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap); 197 return 1; 198 } 199 200 /* 201 * Certain firmware versions are way too sentimential and still believe 202 * they are exclusive and unquestionable owners of the first physical page, 203 * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY 204 * (but then write-access it later during SetVirtualAddressMap()). 205 * 206 * Create a 1:1 mapping for this page, to avoid triple faults during early 207 * boot with such firmware. We are free to hand this page to the BIOS, 208 * as trim_bios_range() will reserve the first page and isolate it away 209 * from memory allocators anyway. 210 */ 211 if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) { 212 pr_err("Failed to create 1:1 mapping for the first page!\n"); 213 return 1; 214 } 215 216 /* 217 * When SEV-ES is active, the GHCB as set by the kernel will be used 218 * by firmware. Create a 1:1 unencrypted mapping for each GHCB. 219 */ 220 if (sev_es_efi_map_ghcbs(pgd)) { 221 pr_err("Failed to create 1:1 mapping for the GHCBs!\n"); 222 return 1; 223 } 224 225 /* 226 * When making calls to the firmware everything needs to be 1:1 227 * mapped and addressable with 32-bit pointers. Map the kernel 228 * text and allocate a new stack because we can't rely on the 229 * stack pointer being < 4GB. 230 */ 231 if (!efi_is_mixed()) 232 return 0; 233 234 page = alloc_page(GFP_KERNEL|__GFP_DMA32); 235 if (!page) { 236 pr_err("Unable to allocate EFI runtime stack < 4GB\n"); 237 return 1; 238 } 239 240 efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */ 241 242 npages = (_etext - _text) >> PAGE_SHIFT; 243 text = __pa(_text); 244 pfn = text >> PAGE_SHIFT; 245 246 pf = _PAGE_ENC; 247 if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, pf)) { 248 pr_err("Failed to map kernel text 1:1\n"); 249 return 1; 250 } 251 252 npages = (__end_rodata - __start_rodata) >> PAGE_SHIFT; 253 rodata = __pa(__start_rodata); 254 pfn = rodata >> PAGE_SHIFT; 255 256 pf = _PAGE_NX | _PAGE_ENC; 257 if (kernel_map_pages_in_pgd(pgd, pfn, rodata, npages, pf)) { 258 pr_err("Failed to map kernel rodata 1:1\n"); 259 return 1; 260 } 261 262 return 0; 263} 264 265static void __init __map_region(efi_memory_desc_t *md, u64 va) 266{ 267 unsigned long flags = _PAGE_RW; 268 unsigned long pfn; 269 pgd_t *pgd = efi_mm.pgd; 270 271 /* 272 * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF 273 * executable images in memory that consist of both R-X and 274 * RW- sections, so we cannot apply read-only or non-exec 275 * permissions just yet. However, modern EFI systems provide 276 * a memory attributes table that describes those sections 277 * with the appropriate restricted permissions, which are 278 * applied in efi_runtime_update_mappings() below. All other 279 * regions can be mapped non-executable at this point, with 280 * the exception of boot services code regions, but those will 281 * be unmapped again entirely in efi_free_boot_services(). 282 */ 283 if (md->type != EFI_BOOT_SERVICES_CODE && 284 md->type != EFI_RUNTIME_SERVICES_CODE) 285 flags |= _PAGE_NX; 286 287 if (!(md->attribute & EFI_MEMORY_WB)) 288 flags |= _PAGE_PCD; 289 290 if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO) 291 flags |= _PAGE_ENC; 292 293 pfn = md->phys_addr >> PAGE_SHIFT; 294 if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags)) 295 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n", 296 md->phys_addr, va); 297} 298 299void __init efi_map_region(efi_memory_desc_t *md) 300{ 301 unsigned long size = md->num_pages << PAGE_SHIFT; 302 u64 pa = md->phys_addr; 303 304 /* 305 * Make sure the 1:1 mappings are present as a catch-all for b0rked 306 * firmware which doesn't update all internal pointers after switching 307 * to virtual mode and would otherwise crap on us. 308 */ 309 __map_region(md, md->phys_addr); 310 311 /* 312 * Enforce the 1:1 mapping as the default virtual address when 313 * booting in EFI mixed mode, because even though we may be 314 * running a 64-bit kernel, the firmware may only be 32-bit. 315 */ 316 if (efi_is_mixed()) { 317 md->virt_addr = md->phys_addr; 318 return; 319 } 320 321 efi_va -= size; 322 323 /* Is PA 2M-aligned? */ 324 if (!(pa & (PMD_SIZE - 1))) { 325 efi_va &= PMD_MASK; 326 } else { 327 u64 pa_offset = pa & (PMD_SIZE - 1); 328 u64 prev_va = efi_va; 329 330 /* get us the same offset within this 2M page */ 331 efi_va = (efi_va & PMD_MASK) + pa_offset; 332 333 if (efi_va > prev_va) 334 efi_va -= PMD_SIZE; 335 } 336 337 if (efi_va < EFI_VA_END) { 338 pr_warn(FW_WARN "VA address range overflow!\n"); 339 return; 340 } 341 342 /* Do the VA map */ 343 __map_region(md, efi_va); 344 md->virt_addr = efi_va; 345} 346 347/* 348 * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges. 349 * md->virt_addr is the original virtual address which had been mapped in kexec 350 * 1st kernel. 351 */ 352void __init efi_map_region_fixed(efi_memory_desc_t *md) 353{ 354 __map_region(md, md->phys_addr); 355 __map_region(md, md->virt_addr); 356} 357 358void __init parse_efi_setup(u64 phys_addr, u32 data_len) 359{ 360 efi_setup = phys_addr + sizeof(struct setup_data); 361} 362 363static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf) 364{ 365 unsigned long pfn; 366 pgd_t *pgd = efi_mm.pgd; 367 int err1, err2; 368 369 /* Update the 1:1 mapping */ 370 pfn = md->phys_addr >> PAGE_SHIFT; 371 err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf); 372 if (err1) { 373 pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n", 374 md->phys_addr, md->virt_addr); 375 } 376 377 err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf); 378 if (err2) { 379 pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n", 380 md->phys_addr, md->virt_addr); 381 } 382 383 return err1 || err2; 384} 385 386static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md) 387{ 388 unsigned long pf = 0; 389 390 if (md->attribute & EFI_MEMORY_XP) 391 pf |= _PAGE_NX; 392 393 if (!(md->attribute & EFI_MEMORY_RO)) 394 pf |= _PAGE_RW; 395 396 if (sev_active()) 397 pf |= _PAGE_ENC; 398 399 return efi_update_mappings(md, pf); 400} 401 402void __init efi_runtime_update_mappings(void) 403{ 404 efi_memory_desc_t *md; 405 406 /* 407 * Use the EFI Memory Attribute Table for mapping permissions if it 408 * exists, since it is intended to supersede EFI_PROPERTIES_TABLE. 409 */ 410 if (efi_enabled(EFI_MEM_ATTR)) { 411 efi_memattr_apply_permissions(NULL, efi_update_mem_attr); 412 return; 413 } 414 415 /* 416 * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace 417 * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update 418 * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not 419 * published by the firmware. Even if we find a buggy implementation of 420 * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to 421 * EFI_PROPERTIES_TABLE, because of the same reason. 422 */ 423 424 if (!efi_enabled(EFI_NX_PE_DATA)) 425 return; 426 427 for_each_efi_memory_desc(md) { 428 unsigned long pf = 0; 429 430 if (!(md->attribute & EFI_MEMORY_RUNTIME)) 431 continue; 432 433 if (!(md->attribute & EFI_MEMORY_WB)) 434 pf |= _PAGE_PCD; 435 436 if ((md->attribute & EFI_MEMORY_XP) || 437 (md->type == EFI_RUNTIME_SERVICES_DATA)) 438 pf |= _PAGE_NX; 439 440 if (!(md->attribute & EFI_MEMORY_RO) && 441 (md->type != EFI_RUNTIME_SERVICES_CODE)) 442 pf |= _PAGE_RW; 443 444 if (sev_active()) 445 pf |= _PAGE_ENC; 446 447 efi_update_mappings(md, pf); 448 } 449} 450 451void __init efi_dump_pagetable(void) 452{ 453#ifdef CONFIG_EFI_PGT_DUMP 454 ptdump_walk_pgd_level(NULL, &efi_mm); 455#endif 456} 457 458/* 459 * Makes the calling thread switch to/from efi_mm context. Can be used 460 * in a kernel thread and user context. Preemption needs to remain disabled 461 * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm 462 * can not change under us. 463 * It should be ensured that there are no concurent calls to this function. 464 */ 465void efi_switch_mm(struct mm_struct *mm) 466{ 467 efi_scratch.prev_mm = current->active_mm; 468 current->active_mm = mm; 469 switch_mm(efi_scratch.prev_mm, mm, NULL); 470} 471 472static DEFINE_SPINLOCK(efi_runtime_lock); 473 474/* 475 * DS and ES contain user values. We need to save them. 476 * The 32-bit EFI code needs a valid DS, ES, and SS. There's no 477 * need to save the old SS: __KERNEL_DS is always acceptable. 478 */ 479#define __efi_thunk(func, ...) \ 480({ \ 481 unsigned short __ds, __es; \ 482 efi_status_t ____s; \ 483 \ 484 savesegment(ds, __ds); \ 485 savesegment(es, __es); \ 486 \ 487 loadsegment(ss, __KERNEL_DS); \ 488 loadsegment(ds, __KERNEL_DS); \ 489 loadsegment(es, __KERNEL_DS); \ 490 \ 491 ____s = efi64_thunk(efi.runtime->mixed_mode.func, __VA_ARGS__); \ 492 \ 493 loadsegment(ds, __ds); \ 494 loadsegment(es, __es); \ 495 \ 496 ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32; \ 497 ____s; \ 498}) 499 500/* 501 * Switch to the EFI page tables early so that we can access the 1:1 502 * runtime services mappings which are not mapped in any other page 503 * tables. 504 * 505 * Also, disable interrupts because the IDT points to 64-bit handlers, 506 * which aren't going to function correctly when we switch to 32-bit. 507 */ 508#define efi_thunk(func...) \ 509({ \ 510 efi_status_t __s; \ 511 \ 512 arch_efi_call_virt_setup(); \ 513 \ 514 __s = __efi_thunk(func); \ 515 \ 516 arch_efi_call_virt_teardown(); \ 517 \ 518 __s; \ 519}) 520 521static efi_status_t __init __no_sanitize_address 522efi_thunk_set_virtual_address_map(unsigned long memory_map_size, 523 unsigned long descriptor_size, 524 u32 descriptor_version, 525 efi_memory_desc_t *virtual_map) 526{ 527 efi_status_t status; 528 unsigned long flags; 529 530 efi_sync_low_kernel_mappings(); 531 local_irq_save(flags); 532 533 efi_switch_mm(&efi_mm); 534 535 status = __efi_thunk(set_virtual_address_map, memory_map_size, 536 descriptor_size, descriptor_version, virtual_map); 537 538 efi_switch_mm(efi_scratch.prev_mm); 539 local_irq_restore(flags); 540 541 return status; 542} 543 544static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc) 545{ 546 return EFI_UNSUPPORTED; 547} 548 549static efi_status_t efi_thunk_set_time(efi_time_t *tm) 550{ 551 return EFI_UNSUPPORTED; 552} 553 554static efi_status_t 555efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending, 556 efi_time_t *tm) 557{ 558 return EFI_UNSUPPORTED; 559} 560 561static efi_status_t 562efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) 563{ 564 return EFI_UNSUPPORTED; 565} 566 567static unsigned long efi_name_size(efi_char16_t *name) 568{ 569 return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1; 570} 571 572static efi_status_t 573efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor, 574 u32 *attr, unsigned long *data_size, void *data) 575{ 576 u8 buf[24] __aligned(8); 577 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 578 efi_status_t status; 579 u32 phys_name, phys_vendor, phys_attr; 580 u32 phys_data_size, phys_data; 581 unsigned long flags; 582 583 spin_lock_irqsave(&efi_runtime_lock, flags); 584 585 *vnd = *vendor; 586 587 phys_data_size = virt_to_phys_or_null(data_size); 588 phys_vendor = virt_to_phys_or_null(vnd); 589 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 590 phys_attr = virt_to_phys_or_null(attr); 591 phys_data = virt_to_phys_or_null_size(data, *data_size); 592 593 if (!phys_name || (data && !phys_data)) 594 status = EFI_INVALID_PARAMETER; 595 else 596 status = efi_thunk(get_variable, phys_name, phys_vendor, 597 phys_attr, phys_data_size, phys_data); 598 599 spin_unlock_irqrestore(&efi_runtime_lock, flags); 600 601 return status; 602} 603 604static efi_status_t 605efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor, 606 u32 attr, unsigned long data_size, void *data) 607{ 608 u8 buf[24] __aligned(8); 609 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 610 u32 phys_name, phys_vendor, phys_data; 611 efi_status_t status; 612 unsigned long flags; 613 614 spin_lock_irqsave(&efi_runtime_lock, flags); 615 616 *vnd = *vendor; 617 618 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 619 phys_vendor = virt_to_phys_or_null(vnd); 620 phys_data = virt_to_phys_or_null_size(data, data_size); 621 622 if (!phys_name || (data && !phys_data)) 623 status = EFI_INVALID_PARAMETER; 624 else 625 status = efi_thunk(set_variable, phys_name, phys_vendor, 626 attr, data_size, phys_data); 627 628 spin_unlock_irqrestore(&efi_runtime_lock, flags); 629 630 return status; 631} 632 633static efi_status_t 634efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor, 635 u32 attr, unsigned long data_size, 636 void *data) 637{ 638 u8 buf[24] __aligned(8); 639 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 640 u32 phys_name, phys_vendor, phys_data; 641 efi_status_t status; 642 unsigned long flags; 643 644 if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) 645 return EFI_NOT_READY; 646 647 *vnd = *vendor; 648 649 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 650 phys_vendor = virt_to_phys_or_null(vnd); 651 phys_data = virt_to_phys_or_null_size(data, data_size); 652 653 if (!phys_name || (data && !phys_data)) 654 status = EFI_INVALID_PARAMETER; 655 else 656 status = efi_thunk(set_variable, phys_name, phys_vendor, 657 attr, data_size, phys_data); 658 659 spin_unlock_irqrestore(&efi_runtime_lock, flags); 660 661 return status; 662} 663 664static efi_status_t 665efi_thunk_get_next_variable(unsigned long *name_size, 666 efi_char16_t *name, 667 efi_guid_t *vendor) 668{ 669 u8 buf[24] __aligned(8); 670 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 671 efi_status_t status; 672 u32 phys_name_size, phys_name, phys_vendor; 673 unsigned long flags; 674 675 spin_lock_irqsave(&efi_runtime_lock, flags); 676 677 *vnd = *vendor; 678 679 phys_name_size = virt_to_phys_or_null(name_size); 680 phys_vendor = virt_to_phys_or_null(vnd); 681 phys_name = virt_to_phys_or_null_size(name, *name_size); 682 683 if (!phys_name) 684 status = EFI_INVALID_PARAMETER; 685 else 686 status = efi_thunk(get_next_variable, phys_name_size, 687 phys_name, phys_vendor); 688 689 spin_unlock_irqrestore(&efi_runtime_lock, flags); 690 691 *vendor = *vnd; 692 return status; 693} 694 695static efi_status_t 696efi_thunk_get_next_high_mono_count(u32 *count) 697{ 698 return EFI_UNSUPPORTED; 699} 700 701static void 702efi_thunk_reset_system(int reset_type, efi_status_t status, 703 unsigned long data_size, efi_char16_t *data) 704{ 705 u32 phys_data; 706 unsigned long flags; 707 708 spin_lock_irqsave(&efi_runtime_lock, flags); 709 710 phys_data = virt_to_phys_or_null_size(data, data_size); 711 712 efi_thunk(reset_system, reset_type, status, data_size, phys_data); 713 714 spin_unlock_irqrestore(&efi_runtime_lock, flags); 715} 716 717static efi_status_t 718efi_thunk_update_capsule(efi_capsule_header_t **capsules, 719 unsigned long count, unsigned long sg_list) 720{ 721 /* 722 * To properly support this function we would need to repackage 723 * 'capsules' because the firmware doesn't understand 64-bit 724 * pointers. 725 */ 726 return EFI_UNSUPPORTED; 727} 728 729static efi_status_t 730efi_thunk_query_variable_info(u32 attr, u64 *storage_space, 731 u64 *remaining_space, 732 u64 *max_variable_size) 733{ 734 efi_status_t status; 735 u32 phys_storage, phys_remaining, phys_max; 736 unsigned long flags; 737 738 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) 739 return EFI_UNSUPPORTED; 740 741 spin_lock_irqsave(&efi_runtime_lock, flags); 742 743 phys_storage = virt_to_phys_or_null(storage_space); 744 phys_remaining = virt_to_phys_or_null(remaining_space); 745 phys_max = virt_to_phys_or_null(max_variable_size); 746 747 status = efi_thunk(query_variable_info, attr, phys_storage, 748 phys_remaining, phys_max); 749 750 spin_unlock_irqrestore(&efi_runtime_lock, flags); 751 752 return status; 753} 754 755static efi_status_t 756efi_thunk_query_variable_info_nonblocking(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 if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) 768 return EFI_NOT_READY; 769 770 phys_storage = virt_to_phys_or_null(storage_space); 771 phys_remaining = virt_to_phys_or_null(remaining_space); 772 phys_max = virt_to_phys_or_null(max_variable_size); 773 774 status = efi_thunk(query_variable_info, attr, phys_storage, 775 phys_remaining, phys_max); 776 777 spin_unlock_irqrestore(&efi_runtime_lock, flags); 778 779 return status; 780} 781 782static efi_status_t 783efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules, 784 unsigned long count, u64 *max_size, 785 int *reset_type) 786{ 787 /* 788 * To properly support this function we would need to repackage 789 * 'capsules' because the firmware doesn't understand 64-bit 790 * pointers. 791 */ 792 return EFI_UNSUPPORTED; 793} 794 795void __init efi_thunk_runtime_setup(void) 796{ 797 if (!IS_ENABLED(CONFIG_EFI_MIXED)) 798 return; 799 800 efi.get_time = efi_thunk_get_time; 801 efi.set_time = efi_thunk_set_time; 802 efi.get_wakeup_time = efi_thunk_get_wakeup_time; 803 efi.set_wakeup_time = efi_thunk_set_wakeup_time; 804 efi.get_variable = efi_thunk_get_variable; 805 efi.get_next_variable = efi_thunk_get_next_variable; 806 efi.set_variable = efi_thunk_set_variable; 807 efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking; 808 efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count; 809 efi.reset_system = efi_thunk_reset_system; 810 efi.query_variable_info = efi_thunk_query_variable_info; 811 efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking; 812 efi.update_capsule = efi_thunk_update_capsule; 813 efi.query_capsule_caps = efi_thunk_query_capsule_caps; 814} 815 816efi_status_t __init __no_sanitize_address 817efi_set_virtual_address_map(unsigned long memory_map_size, 818 unsigned long descriptor_size, 819 u32 descriptor_version, 820 efi_memory_desc_t *virtual_map, 821 unsigned long systab_phys) 822{ 823 const efi_system_table_t *systab = (efi_system_table_t *)systab_phys; 824 efi_status_t status; 825 unsigned long flags; 826 827 if (efi_is_mixed()) 828 return efi_thunk_set_virtual_address_map(memory_map_size, 829 descriptor_size, 830 descriptor_version, 831 virtual_map); 832 efi_switch_mm(&efi_mm); 833 834 kernel_fpu_begin(); 835 836 /* Disable interrupts around EFI calls: */ 837 local_irq_save(flags); 838 status = efi_call(efi.runtime->set_virtual_address_map, 839 memory_map_size, descriptor_size, 840 descriptor_version, virtual_map); 841 local_irq_restore(flags); 842 843 kernel_fpu_end(); 844 845 /* grab the virtually remapped EFI runtime services table pointer */ 846 efi.runtime = READ_ONCE(systab->runtime); 847 848 efi_switch_mm(efi_scratch.prev_mm); 849 850 return status; 851} 852