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 */ 56static u64 efi_va = EFI_VA_START; 57static 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 */ 68int __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 95free_p4d: 96 if (pgtable_l5_enabled()) 97 free_page((unsigned long)pgd_page_vaddr(*pgd)); 98free_pgd: 99 free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER); 100fail: 101 return -ENOMEM; 102} 103 104/* 105 * Add low kernel mappings for passing arguments to EFI functions. 106 */ 107void 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 */ 154static inline phys_addr_t 155virt_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 177int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages) 178{ 179 extern const u8 __efi64_thunk_ret_tramp[]; 180 unsigned long pfn, text, pf, rodata, tramp; 181 struct page *page; 182 unsigned npages; 183 pgd_t *pgd = efi_mm.pgd; 184 185 /* 186 * It can happen that the physical address of new_memmap lands in memory 187 * which is not mapped in the EFI page table. Therefore we need to go 188 * and ident-map those pages containing the map before calling 189 * phys_efi_set_virtual_address_map(). 190 */ 191 pfn = pa_memmap >> PAGE_SHIFT; 192 pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC; 193 if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) { 194 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap); 195 return 1; 196 } 197 198 /* 199 * Certain firmware versions are way too sentimental and still believe 200 * they are exclusive and unquestionable owners of the first physical page, 201 * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY 202 * (but then write-access it later during SetVirtualAddressMap()). 203 * 204 * Create a 1:1 mapping for this page, to avoid triple faults during early 205 * boot with such firmware. We are free to hand this page to the BIOS, 206 * as trim_bios_range() will reserve the first page and isolate it away 207 * from memory allocators anyway. 208 */ 209 if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) { 210 pr_err("Failed to create 1:1 mapping for the first page!\n"); 211 return 1; 212 } 213 214 /* 215 * When SEV-ES is active, the GHCB as set by the kernel will be used 216 * by firmware. Create a 1:1 unencrypted mapping for each GHCB. 217 */ 218 if (sev_es_efi_map_ghcbs(pgd)) { 219 pr_err("Failed to create 1:1 mapping for the GHCBs!\n"); 220 return 1; 221 } 222 223 /* 224 * When making calls to the firmware everything needs to be 1:1 225 * mapped and addressable with 32-bit pointers. Map the kernel 226 * text and allocate a new stack because we can't rely on the 227 * stack pointer being < 4GB. 228 */ 229 if (!efi_is_mixed()) 230 return 0; 231 232 page = alloc_page(GFP_KERNEL|__GFP_DMA32); 233 if (!page) { 234 pr_err("Unable to allocate EFI runtime stack < 4GB\n"); 235 return 1; 236 } 237 238 efi_mixed_mode_stack_pa = page_to_phys(page + 1); /* stack grows down */ 239 240 npages = (_etext - _text) >> PAGE_SHIFT; 241 text = __pa(_text); 242 243 if (kernel_unmap_pages_in_pgd(pgd, text, npages)) { 244 pr_err("Failed to unmap kernel text 1:1 mapping\n"); 245 return 1; 246 } 247 248 npages = (__end_rodata - __start_rodata) >> PAGE_SHIFT; 249 rodata = __pa(__start_rodata); 250 pfn = rodata >> PAGE_SHIFT; 251 252 pf = _PAGE_NX | _PAGE_ENC; 253 if (kernel_map_pages_in_pgd(pgd, pfn, rodata, npages, pf)) { 254 pr_err("Failed to map kernel rodata 1:1\n"); 255 return 1; 256 } 257 258 tramp = __pa(__efi64_thunk_ret_tramp); 259 pfn = tramp >> PAGE_SHIFT; 260 261 pf = _PAGE_ENC; 262 if (kernel_map_pages_in_pgd(pgd, pfn, tramp, 1, pf)) { 263 pr_err("Failed to map mixed mode return trampoline\n"); 264 return 1; 265 } 266 267 return 0; 268} 269 270static void __init __map_region(efi_memory_desc_t *md, u64 va) 271{ 272 unsigned long flags = _PAGE_RW; 273 unsigned long pfn; 274 pgd_t *pgd = efi_mm.pgd; 275 276 /* 277 * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF 278 * executable images in memory that consist of both R-X and 279 * RW- sections, so we cannot apply read-only or non-exec 280 * permissions just yet. However, modern EFI systems provide 281 * a memory attributes table that describes those sections 282 * with the appropriate restricted permissions, which are 283 * applied in efi_runtime_update_mappings() below. All other 284 * regions can be mapped non-executable at this point, with 285 * the exception of boot services code regions, but those will 286 * be unmapped again entirely in efi_free_boot_services(). 287 */ 288 if (md->type != EFI_BOOT_SERVICES_CODE && 289 md->type != EFI_RUNTIME_SERVICES_CODE) 290 flags |= _PAGE_NX; 291 292 if (!(md->attribute & EFI_MEMORY_WB)) 293 flags |= _PAGE_PCD; 294 295 if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT) && 296 md->type != EFI_MEMORY_MAPPED_IO) 297 flags |= _PAGE_ENC; 298 299 pfn = md->phys_addr >> PAGE_SHIFT; 300 if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags)) 301 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n", 302 md->phys_addr, va); 303} 304 305void __init efi_map_region(efi_memory_desc_t *md) 306{ 307 unsigned long size = md->num_pages << PAGE_SHIFT; 308 u64 pa = md->phys_addr; 309 310 /* 311 * Make sure the 1:1 mappings are present as a catch-all for b0rked 312 * firmware which doesn't update all internal pointers after switching 313 * to virtual mode and would otherwise crap on us. 314 */ 315 __map_region(md, md->phys_addr); 316 317 /* 318 * Enforce the 1:1 mapping as the default virtual address when 319 * booting in EFI mixed mode, because even though we may be 320 * running a 64-bit kernel, the firmware may only be 32-bit. 321 */ 322 if (efi_is_mixed()) { 323 md->virt_addr = md->phys_addr; 324 return; 325 } 326 327 efi_va -= size; 328 329 /* Is PA 2M-aligned? */ 330 if (!(pa & (PMD_SIZE - 1))) { 331 efi_va &= PMD_MASK; 332 } else { 333 u64 pa_offset = pa & (PMD_SIZE - 1); 334 u64 prev_va = efi_va; 335 336 /* get us the same offset within this 2M page */ 337 efi_va = (efi_va & PMD_MASK) + pa_offset; 338 339 if (efi_va > prev_va) 340 efi_va -= PMD_SIZE; 341 } 342 343 if (efi_va < EFI_VA_END) { 344 pr_warn(FW_WARN "VA address range overflow!\n"); 345 return; 346 } 347 348 /* Do the VA map */ 349 __map_region(md, efi_va); 350 md->virt_addr = efi_va; 351} 352 353/* 354 * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges. 355 * md->virt_addr is the original virtual address which had been mapped in kexec 356 * 1st kernel. 357 */ 358void __init efi_map_region_fixed(efi_memory_desc_t *md) 359{ 360 __map_region(md, md->phys_addr); 361 __map_region(md, md->virt_addr); 362} 363 364void __init parse_efi_setup(u64 phys_addr, u32 data_len) 365{ 366 efi_setup = phys_addr + sizeof(struct setup_data); 367} 368 369static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf) 370{ 371 unsigned long pfn; 372 pgd_t *pgd = efi_mm.pgd; 373 int err1, err2; 374 375 /* Update the 1:1 mapping */ 376 pfn = md->phys_addr >> PAGE_SHIFT; 377 err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf); 378 if (err1) { 379 pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n", 380 md->phys_addr, md->virt_addr); 381 } 382 383 err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf); 384 if (err2) { 385 pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n", 386 md->phys_addr, md->virt_addr); 387 } 388 389 return err1 || err2; 390} 391 392bool efi_disable_ibt_for_runtime __ro_after_init = true; 393 394static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md, 395 bool has_ibt) 396{ 397 unsigned long pf = 0; 398 399 efi_disable_ibt_for_runtime |= !has_ibt; 400 401 if (md->attribute & EFI_MEMORY_XP) 402 pf |= _PAGE_NX; 403 404 if (!(md->attribute & EFI_MEMORY_RO)) 405 pf |= _PAGE_RW; 406 407 if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) 408 pf |= _PAGE_ENC; 409 410 return efi_update_mappings(md, pf); 411} 412 413void __init efi_runtime_update_mappings(void) 414{ 415 efi_memory_desc_t *md; 416 417 /* 418 * Use the EFI Memory Attribute Table for mapping permissions if it 419 * exists, since it is intended to supersede EFI_PROPERTIES_TABLE. 420 */ 421 if (efi_enabled(EFI_MEM_ATTR)) { 422 efi_disable_ibt_for_runtime = false; 423 efi_memattr_apply_permissions(NULL, efi_update_mem_attr); 424 return; 425 } 426 427 /* 428 * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace 429 * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update 430 * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not 431 * published by the firmware. Even if we find a buggy implementation of 432 * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to 433 * EFI_PROPERTIES_TABLE, because of the same reason. 434 */ 435 436 if (!efi_enabled(EFI_NX_PE_DATA)) 437 return; 438 439 for_each_efi_memory_desc(md) { 440 unsigned long pf = 0; 441 442 if (!(md->attribute & EFI_MEMORY_RUNTIME)) 443 continue; 444 445 if (!(md->attribute & EFI_MEMORY_WB)) 446 pf |= _PAGE_PCD; 447 448 if ((md->attribute & EFI_MEMORY_XP) || 449 (md->type == EFI_RUNTIME_SERVICES_DATA)) 450 pf |= _PAGE_NX; 451 452 if (!(md->attribute & EFI_MEMORY_RO) && 453 (md->type != EFI_RUNTIME_SERVICES_CODE)) 454 pf |= _PAGE_RW; 455 456 if (cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT)) 457 pf |= _PAGE_ENC; 458 459 efi_update_mappings(md, pf); 460 } 461} 462 463void __init efi_dump_pagetable(void) 464{ 465#ifdef CONFIG_EFI_PGT_DUMP 466 ptdump_walk_pgd_level(NULL, &efi_mm); 467#endif 468} 469 470/* 471 * Makes the calling thread switch to/from efi_mm context. Can be used 472 * in a kernel thread and user context. Preemption needs to remain disabled 473 * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm 474 * can not change under us. 475 * It should be ensured that there are no concurrent calls to this function. 476 */ 477static void efi_enter_mm(void) 478{ 479 efi_prev_mm = current->active_mm; 480 current->active_mm = &efi_mm; 481 switch_mm(efi_prev_mm, &efi_mm, NULL); 482} 483 484static void efi_leave_mm(void) 485{ 486 current->active_mm = efi_prev_mm; 487 switch_mm(&efi_mm, efi_prev_mm, NULL); 488} 489 490void arch_efi_call_virt_setup(void) 491{ 492 efi_sync_low_kernel_mappings(); 493 efi_fpu_begin(); 494 firmware_restrict_branch_speculation_start(); 495 efi_enter_mm(); 496} 497 498void arch_efi_call_virt_teardown(void) 499{ 500 efi_leave_mm(); 501 firmware_restrict_branch_speculation_end(); 502 efi_fpu_end(); 503} 504 505static DEFINE_SPINLOCK(efi_runtime_lock); 506 507/* 508 * DS and ES contain user values. We need to save them. 509 * The 32-bit EFI code needs a valid DS, ES, and SS. There's no 510 * need to save the old SS: __KERNEL_DS is always acceptable. 511 */ 512#define __efi_thunk(func, ...) \ 513({ \ 514 unsigned short __ds, __es; \ 515 efi_status_t ____s; \ 516 \ 517 savesegment(ds, __ds); \ 518 savesegment(es, __es); \ 519 \ 520 loadsegment(ss, __KERNEL_DS); \ 521 loadsegment(ds, __KERNEL_DS); \ 522 loadsegment(es, __KERNEL_DS); \ 523 \ 524 ____s = efi64_thunk(efi.runtime->mixed_mode.func, __VA_ARGS__); \ 525 \ 526 loadsegment(ds, __ds); \ 527 loadsegment(es, __es); \ 528 \ 529 ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32; \ 530 ____s; \ 531}) 532 533/* 534 * Switch to the EFI page tables early so that we can access the 1:1 535 * runtime services mappings which are not mapped in any other page 536 * tables. 537 * 538 * Also, disable interrupts because the IDT points to 64-bit handlers, 539 * which aren't going to function correctly when we switch to 32-bit. 540 */ 541#define efi_thunk(func...) \ 542({ \ 543 efi_status_t __s; \ 544 \ 545 arch_efi_call_virt_setup(); \ 546 \ 547 __s = __efi_thunk(func); \ 548 \ 549 arch_efi_call_virt_teardown(); \ 550 \ 551 __s; \ 552}) 553 554static efi_status_t __init __no_sanitize_address 555efi_thunk_set_virtual_address_map(unsigned long memory_map_size, 556 unsigned long descriptor_size, 557 u32 descriptor_version, 558 efi_memory_desc_t *virtual_map) 559{ 560 efi_status_t status; 561 unsigned long flags; 562 563 efi_sync_low_kernel_mappings(); 564 local_irq_save(flags); 565 566 efi_enter_mm(); 567 568 status = __efi_thunk(set_virtual_address_map, memory_map_size, 569 descriptor_size, descriptor_version, virtual_map); 570 571 efi_leave_mm(); 572 local_irq_restore(flags); 573 574 return status; 575} 576 577static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc) 578{ 579 return EFI_UNSUPPORTED; 580} 581 582static efi_status_t efi_thunk_set_time(efi_time_t *tm) 583{ 584 return EFI_UNSUPPORTED; 585} 586 587static efi_status_t 588efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending, 589 efi_time_t *tm) 590{ 591 return EFI_UNSUPPORTED; 592} 593 594static efi_status_t 595efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) 596{ 597 return EFI_UNSUPPORTED; 598} 599 600static unsigned long efi_name_size(efi_char16_t *name) 601{ 602 return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1; 603} 604 605static efi_status_t 606efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor, 607 u32 *attr, unsigned long *data_size, void *data) 608{ 609 u8 buf[24] __aligned(8); 610 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 611 efi_status_t status; 612 u32 phys_name, phys_vendor, phys_attr; 613 u32 phys_data_size, phys_data; 614 unsigned long flags; 615 616 spin_lock_irqsave(&efi_runtime_lock, flags); 617 618 *vnd = *vendor; 619 620 phys_data_size = virt_to_phys_or_null(data_size); 621 phys_vendor = virt_to_phys_or_null(vnd); 622 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 623 phys_attr = virt_to_phys_or_null(attr); 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(get_variable, phys_name, phys_vendor, 630 phys_attr, phys_data_size, phys_data); 631 632 spin_unlock_irqrestore(&efi_runtime_lock, flags); 633 634 return status; 635} 636 637static efi_status_t 638efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor, 639 u32 attr, unsigned long data_size, void *data) 640{ 641 u8 buf[24] __aligned(8); 642 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 643 u32 phys_name, phys_vendor, phys_data; 644 efi_status_t status; 645 unsigned long flags; 646 647 spin_lock_irqsave(&efi_runtime_lock, flags); 648 649 *vnd = *vendor; 650 651 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 652 phys_vendor = virt_to_phys_or_null(vnd); 653 phys_data = virt_to_phys_or_null_size(data, data_size); 654 655 if (!phys_name || (data && !phys_data)) 656 status = EFI_INVALID_PARAMETER; 657 else 658 status = efi_thunk(set_variable, phys_name, phys_vendor, 659 attr, data_size, phys_data); 660 661 spin_unlock_irqrestore(&efi_runtime_lock, flags); 662 663 return status; 664} 665 666static efi_status_t 667efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor, 668 u32 attr, unsigned long data_size, 669 void *data) 670{ 671 u8 buf[24] __aligned(8); 672 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 673 u32 phys_name, phys_vendor, phys_data; 674 efi_status_t status; 675 unsigned long flags; 676 677 if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) 678 return EFI_NOT_READY; 679 680 *vnd = *vendor; 681 682 phys_name = virt_to_phys_or_null_size(name, efi_name_size(name)); 683 phys_vendor = virt_to_phys_or_null(vnd); 684 phys_data = virt_to_phys_or_null_size(data, data_size); 685 686 if (!phys_name || (data && !phys_data)) 687 status = EFI_INVALID_PARAMETER; 688 else 689 status = efi_thunk(set_variable, phys_name, phys_vendor, 690 attr, data_size, phys_data); 691 692 spin_unlock_irqrestore(&efi_runtime_lock, flags); 693 694 return status; 695} 696 697static efi_status_t 698efi_thunk_get_next_variable(unsigned long *name_size, 699 efi_char16_t *name, 700 efi_guid_t *vendor) 701{ 702 u8 buf[24] __aligned(8); 703 efi_guid_t *vnd = PTR_ALIGN((efi_guid_t *)buf, sizeof(*vnd)); 704 efi_status_t status; 705 u32 phys_name_size, phys_name, phys_vendor; 706 unsigned long flags; 707 708 spin_lock_irqsave(&efi_runtime_lock, flags); 709 710 *vnd = *vendor; 711 712 phys_name_size = virt_to_phys_or_null(name_size); 713 phys_vendor = virt_to_phys_or_null(vnd); 714 phys_name = virt_to_phys_or_null_size(name, *name_size); 715 716 if (!phys_name) 717 status = EFI_INVALID_PARAMETER; 718 else 719 status = efi_thunk(get_next_variable, phys_name_size, 720 phys_name, phys_vendor); 721 722 spin_unlock_irqrestore(&efi_runtime_lock, flags); 723 724 *vendor = *vnd; 725 return status; 726} 727 728static efi_status_t 729efi_thunk_get_next_high_mono_count(u32 *count) 730{ 731 return EFI_UNSUPPORTED; 732} 733 734static void 735efi_thunk_reset_system(int reset_type, efi_status_t status, 736 unsigned long data_size, efi_char16_t *data) 737{ 738 u32 phys_data; 739 unsigned long flags; 740 741 spin_lock_irqsave(&efi_runtime_lock, flags); 742 743 phys_data = virt_to_phys_or_null_size(data, data_size); 744 745 efi_thunk(reset_system, reset_type, status, data_size, phys_data); 746 747 spin_unlock_irqrestore(&efi_runtime_lock, flags); 748} 749 750static efi_status_t 751efi_thunk_update_capsule(efi_capsule_header_t **capsules, 752 unsigned long count, unsigned long sg_list) 753{ 754 /* 755 * To properly support this function we would need to repackage 756 * 'capsules' because the firmware doesn't understand 64-bit 757 * pointers. 758 */ 759 return EFI_UNSUPPORTED; 760} 761 762static efi_status_t 763efi_thunk_query_variable_info(u32 attr, u64 *storage_space, 764 u64 *remaining_space, 765 u64 *max_variable_size) 766{ 767 efi_status_t status; 768 u32 phys_storage, phys_remaining, phys_max; 769 unsigned long flags; 770 771 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) 772 return EFI_UNSUPPORTED; 773 774 spin_lock_irqsave(&efi_runtime_lock, flags); 775 776 phys_storage = virt_to_phys_or_null(storage_space); 777 phys_remaining = virt_to_phys_or_null(remaining_space); 778 phys_max = virt_to_phys_or_null(max_variable_size); 779 780 status = efi_thunk(query_variable_info, attr, phys_storage, 781 phys_remaining, phys_max); 782 783 spin_unlock_irqrestore(&efi_runtime_lock, flags); 784 785 return status; 786} 787 788static efi_status_t 789efi_thunk_query_variable_info_nonblocking(u32 attr, u64 *storage_space, 790 u64 *remaining_space, 791 u64 *max_variable_size) 792{ 793 efi_status_t status; 794 u32 phys_storage, phys_remaining, phys_max; 795 unsigned long flags; 796 797 if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION) 798 return EFI_UNSUPPORTED; 799 800 if (!spin_trylock_irqsave(&efi_runtime_lock, flags)) 801 return EFI_NOT_READY; 802 803 phys_storage = virt_to_phys_or_null(storage_space); 804 phys_remaining = virt_to_phys_or_null(remaining_space); 805 phys_max = virt_to_phys_or_null(max_variable_size); 806 807 status = efi_thunk(query_variable_info, attr, phys_storage, 808 phys_remaining, phys_max); 809 810 spin_unlock_irqrestore(&efi_runtime_lock, flags); 811 812 return status; 813} 814 815static efi_status_t 816efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules, 817 unsigned long count, u64 *max_size, 818 int *reset_type) 819{ 820 /* 821 * To properly support this function we would need to repackage 822 * 'capsules' because the firmware doesn't understand 64-bit 823 * pointers. 824 */ 825 return EFI_UNSUPPORTED; 826} 827 828void __init efi_thunk_runtime_setup(void) 829{ 830 if (!IS_ENABLED(CONFIG_EFI_MIXED)) 831 return; 832 833 efi.get_time = efi_thunk_get_time; 834 efi.set_time = efi_thunk_set_time; 835 efi.get_wakeup_time = efi_thunk_get_wakeup_time; 836 efi.set_wakeup_time = efi_thunk_set_wakeup_time; 837 efi.get_variable = efi_thunk_get_variable; 838 efi.get_next_variable = efi_thunk_get_next_variable; 839 efi.set_variable = efi_thunk_set_variable; 840 efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking; 841 efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count; 842 efi.reset_system = efi_thunk_reset_system; 843 efi.query_variable_info = efi_thunk_query_variable_info; 844 efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking; 845 efi.update_capsule = efi_thunk_update_capsule; 846 efi.query_capsule_caps = efi_thunk_query_capsule_caps; 847} 848 849efi_status_t __init __no_sanitize_address 850efi_set_virtual_address_map(unsigned long memory_map_size, 851 unsigned long descriptor_size, 852 u32 descriptor_version, 853 efi_memory_desc_t *virtual_map, 854 unsigned long systab_phys) 855{ 856 const efi_system_table_t *systab = (efi_system_table_t *)systab_phys; 857 efi_status_t status; 858 unsigned long flags; 859 860 if (efi_is_mixed()) 861 return efi_thunk_set_virtual_address_map(memory_map_size, 862 descriptor_size, 863 descriptor_version, 864 virtual_map); 865 efi_enter_mm(); 866 867 efi_fpu_begin(); 868 869 /* Disable interrupts around EFI calls: */ 870 local_irq_save(flags); 871 status = arch_efi_call_virt(efi.runtime, set_virtual_address_map, 872 memory_map_size, descriptor_size, 873 descriptor_version, virtual_map); 874 local_irq_restore(flags); 875 876 efi_fpu_end(); 877 878 /* grab the virtually remapped EFI runtime services table pointer */ 879 efi.runtime = READ_ONCE(systab->runtime); 880 881 efi_leave_mm(); 882 883 return status; 884} 885