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(mm: &init_mm, pgd, EFI_VA_END); |
82 | if (!p4d) |
83 | goto free_pgd; |
84 | |
85 | pud = pud_alloc(mm: &init_mm, p4d, EFI_VA_END); |
86 | if (!pud) |
87 | goto free_p4d; |
88 | |
89 | efi_mm.pgd = efi_pgd; |
90 | mm_init_cpumask(mm: &efi_mm); |
91 | init_new_context(NULL, mm: &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(addr: (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: pgd_efi, address: 0); |
124 | p4d_k = p4d_offset(pgd: pgd_k, address: 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: pgd_efi, EFI_VA_END); |
137 | p4d_k = p4d_offset(pgd: pgd_k, EFI_VA_END); |
138 | pud_efi = pud_offset(p4d: p4d_efi, address: 0); |
139 | pud_k = pud_offset(p4d: p4d_k, address: 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: p4d_efi, EFI_VA_START); |
145 | pud_k = pud_offset(p4d: 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(address: va); |
164 | |
165 | pa = slow_virt_to_phys(address: 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 | 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, address: pa_memmap, numpages: num_pages, page_flags: 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, pfn: 0x0, address: 0x0, numpages: 1, page_flags: 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, address: text, numpages: 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, address: rodata, numpages: npages, page_flags: 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, address: tramp, numpages: 1, page_flags: pf)) { |
263 | pr_err("Failed to map mixed mode return trampoline\n" ); |
264 | return 1; |
265 | } |
266 | |
267 | return 0; |
268 | } |
269 | |
270 | static 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(attr: 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, address: va, numpages: md->num_pages, page_flags: flags)) |
301 | pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n" , |
302 | md->phys_addr, va); |
303 | } |
304 | |
305 | void __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, va: 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, va: 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 | */ |
358 | void __init efi_map_region_fixed(efi_memory_desc_t *md) |
359 | { |
360 | __map_region(md, va: md->phys_addr); |
361 | __map_region(md, va: md->virt_addr); |
362 | } |
363 | |
364 | void __init parse_efi_setup(u64 phys_addr, u32 data_len) |
365 | { |
366 | efi_setup = phys_addr + sizeof(struct setup_data); |
367 | } |
368 | |
369 | static 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, address: md->phys_addr, numpages: md->num_pages, page_flags: 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, address: md->virt_addr, numpages: md->num_pages, page_flags: 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 | |
392 | bool efi_disable_ibt_for_runtime __ro_after_init = true; |
393 | |
394 | static 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(attr: CC_ATTR_GUEST_MEM_ENCRYPT)) |
408 | pf |= _PAGE_ENC; |
409 | |
410 | return efi_update_mappings(md, pf); |
411 | } |
412 | |
413 | void __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, fn: 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(attr: CC_ATTR_GUEST_MEM_ENCRYPT)) |
457 | pf |= _PAGE_ENC; |
458 | |
459 | efi_update_mappings(md, pf); |
460 | } |
461 | } |
462 | |
463 | void __init efi_dump_pagetable(void) |
464 | { |
465 | #ifdef CONFIG_EFI_PGT_DUMP |
466 | ptdump_walk_pgd_level(NULL, mm: &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 | */ |
477 | static void efi_enter_mm(void) |
478 | { |
479 | efi_prev_mm = current->active_mm; |
480 | current->active_mm = &efi_mm; |
481 | switch_mm(prev: efi_prev_mm, next: &efi_mm, NULL); |
482 | } |
483 | |
484 | static void efi_leave_mm(void) |
485 | { |
486 | current->active_mm = efi_prev_mm; |
487 | switch_mm(prev: &efi_mm, next: efi_prev_mm, NULL); |
488 | } |
489 | |
490 | void 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 | |
498 | void arch_efi_call_virt_teardown(void) |
499 | { |
500 | efi_leave_mm(); |
501 | firmware_restrict_branch_speculation_end(); |
502 | efi_fpu_end(); |
503 | } |
504 | |
505 | static 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 | |
554 | static efi_status_t __init __no_sanitize_address |
555 | efi_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 | |
577 | static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc) |
578 | { |
579 | return EFI_UNSUPPORTED; |
580 | } |
581 | |
582 | static efi_status_t efi_thunk_set_time(efi_time_t *tm) |
583 | { |
584 | return EFI_UNSUPPORTED; |
585 | } |
586 | |
587 | static efi_status_t |
588 | efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending, |
589 | efi_time_t *tm) |
590 | { |
591 | return EFI_UNSUPPORTED; |
592 | } |
593 | |
594 | static efi_status_t |
595 | efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm) |
596 | { |
597 | return EFI_UNSUPPORTED; |
598 | } |
599 | |
600 | static unsigned long efi_name_size(efi_char16_t *name) |
601 | { |
602 | return ucs2_strsize(data: name, EFI_VAR_NAME_LEN) + 1; |
603 | } |
604 | |
605 | static efi_status_t |
606 | efi_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(va: name, size: efi_name_size(name)); |
623 | phys_attr = virt_to_phys_or_null(attr); |
624 | phys_data = virt_to_phys_or_null_size(va: data, size: *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(lock: &efi_runtime_lock, flags); |
633 | |
634 | return status; |
635 | } |
636 | |
637 | static efi_status_t |
638 | efi_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(va: name, size: efi_name_size(name)); |
652 | phys_vendor = virt_to_phys_or_null(vnd); |
653 | phys_data = virt_to_phys_or_null_size(va: data, size: 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(lock: &efi_runtime_lock, flags); |
662 | |
663 | return status; |
664 | } |
665 | |
666 | static efi_status_t |
667 | efi_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(va: name, size: efi_name_size(name)); |
683 | phys_vendor = virt_to_phys_or_null(vnd); |
684 | phys_data = virt_to_phys_or_null_size(va: data, size: 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(lock: &efi_runtime_lock, flags); |
693 | |
694 | return status; |
695 | } |
696 | |
697 | static efi_status_t |
698 | efi_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(va: name, size: *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(lock: &efi_runtime_lock, flags); |
723 | |
724 | *vendor = *vnd; |
725 | return status; |
726 | } |
727 | |
728 | static efi_status_t |
729 | efi_thunk_get_next_high_mono_count(u32 *count) |
730 | { |
731 | return EFI_UNSUPPORTED; |
732 | } |
733 | |
734 | static void |
735 | efi_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(va: data, size: data_size); |
744 | |
745 | efi_thunk(reset_system, reset_type, status, data_size, phys_data); |
746 | |
747 | spin_unlock_irqrestore(lock: &efi_runtime_lock, flags); |
748 | } |
749 | |
750 | static efi_status_t |
751 | efi_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 | |
762 | static efi_status_t |
763 | efi_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(lock: &efi_runtime_lock, flags); |
784 | |
785 | return status; |
786 | } |
787 | |
788 | static efi_status_t |
789 | efi_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(lock: &efi_runtime_lock, flags); |
811 | |
812 | return status; |
813 | } |
814 | |
815 | static efi_status_t |
816 | efi_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 | |
828 | void __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 | |
849 | efi_status_t __init __no_sanitize_address |
850 | efi_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 | |