]> asedeno.scripts.mit.edu Git - linux.git/blob - arch/x86/platform/efi/efi_64.c
Merge tag 'pci-v5.6-fixes-1' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci
[linux.git] / arch / x86 / platform / efi / efi_64.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * x86_64 specific EFI support functions
4  * Based on Extensible Firmware Interface Specification version 1.0
5  *
6  * Copyright (C) 2005-2008 Intel Co.
7  *      Fenghua Yu <fenghua.yu@intel.com>
8  *      Bibo Mao <bibo.mao@intel.com>
9  *      Chandramouli Narayanan <mouli@linux.intel.com>
10  *      Huang Ying <ying.huang@intel.com>
11  *
12  * Code to convert EFI to E820 map has been implemented in elilo bootloader
13  * based on a EFI patch by Edgar Hucek. Based on the E820 map, the page table
14  * is setup appropriately for EFI runtime code.
15  * - mouli 06/14/2007.
16  *
17  */
18
19 #define pr_fmt(fmt) "efi: " fmt
20
21 #include <linux/kernel.h>
22 #include <linux/init.h>
23 #include <linux/mm.h>
24 #include <linux/types.h>
25 #include <linux/spinlock.h>
26 #include <linux/memblock.h>
27 #include <linux/ioport.h>
28 #include <linux/mc146818rtc.h>
29 #include <linux/efi.h>
30 #include <linux/export.h>
31 #include <linux/uaccess.h>
32 #include <linux/io.h>
33 #include <linux/reboot.h>
34 #include <linux/slab.h>
35 #include <linux/ucs2_string.h>
36 #include <linux/mem_encrypt.h>
37 #include <linux/sched/task.h>
38
39 #include <asm/setup.h>
40 #include <asm/page.h>
41 #include <asm/e820/api.h>
42 #include <asm/pgtable.h>
43 #include <asm/tlbflush.h>
44 #include <asm/proto.h>
45 #include <asm/efi.h>
46 #include <asm/cacheflush.h>
47 #include <asm/fixmap.h>
48 #include <asm/realmode.h>
49 #include <asm/time.h>
50 #include <asm/pgalloc.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
58 struct efi_scratch efi_scratch;
59
60 EXPORT_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  */
71 int __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         if (efi_have_uv1_memmap())
79                 return 0;
80
81         gfp_mask = GFP_KERNEL | __GFP_ZERO;
82         efi_pgd = (pgd_t *)__get_free_pages(gfp_mask, PGD_ALLOCATION_ORDER);
83         if (!efi_pgd)
84                 return -ENOMEM;
85
86         pgd = efi_pgd + pgd_index(EFI_VA_END);
87         p4d = p4d_alloc(&init_mm, pgd, EFI_VA_END);
88         if (!p4d) {
89                 free_page((unsigned long)efi_pgd);
90                 return -ENOMEM;
91         }
92
93         pud = pud_alloc(&init_mm, p4d, EFI_VA_END);
94         if (!pud) {
95                 if (pgtable_l5_enabled())
96                         free_page((unsigned long) pgd_page_vaddr(*pgd));
97                 free_pages((unsigned long)efi_pgd, PGD_ALLOCATION_ORDER);
98                 return -ENOMEM;
99         }
100
101         efi_mm.pgd = efi_pgd;
102         mm_init_cpumask(&efi_mm);
103         init_new_context(NULL, &efi_mm);
104
105         return 0;
106 }
107
108 /*
109  * Add low kernel mappings for passing arguments to EFI functions.
110  */
111 void efi_sync_low_kernel_mappings(void)
112 {
113         unsigned num_entries;
114         pgd_t *pgd_k, *pgd_efi;
115         p4d_t *p4d_k, *p4d_efi;
116         pud_t *pud_k, *pud_efi;
117         pgd_t *efi_pgd = efi_mm.pgd;
118
119         if (efi_have_uv1_memmap())
120                 return;
121
122         /*
123          * We can share all PGD entries apart from the one entry that
124          * covers the EFI runtime mapping space.
125          *
126          * Make sure the EFI runtime region mappings are guaranteed to
127          * only span a single PGD entry and that the entry also maps
128          * other important kernel regions.
129          */
130         MAYBE_BUILD_BUG_ON(pgd_index(EFI_VA_END) != pgd_index(MODULES_END));
131         MAYBE_BUILD_BUG_ON((EFI_VA_START & PGDIR_MASK) !=
132                         (EFI_VA_END & PGDIR_MASK));
133
134         pgd_efi = efi_pgd + pgd_index(PAGE_OFFSET);
135         pgd_k = pgd_offset_k(PAGE_OFFSET);
136
137         num_entries = pgd_index(EFI_VA_END) - pgd_index(PAGE_OFFSET);
138         memcpy(pgd_efi, pgd_k, sizeof(pgd_t) * num_entries);
139
140         /*
141          * As with PGDs, we share all P4D entries apart from the one entry
142          * that covers the EFI runtime mapping space.
143          */
144         BUILD_BUG_ON(p4d_index(EFI_VA_END) != p4d_index(MODULES_END));
145         BUILD_BUG_ON((EFI_VA_START & P4D_MASK) != (EFI_VA_END & P4D_MASK));
146
147         pgd_efi = efi_pgd + pgd_index(EFI_VA_END);
148         pgd_k = pgd_offset_k(EFI_VA_END);
149         p4d_efi = p4d_offset(pgd_efi, 0);
150         p4d_k = p4d_offset(pgd_k, 0);
151
152         num_entries = p4d_index(EFI_VA_END);
153         memcpy(p4d_efi, p4d_k, sizeof(p4d_t) * num_entries);
154
155         /*
156          * We share all the PUD entries apart from those that map the
157          * EFI regions. Copy around them.
158          */
159         BUILD_BUG_ON((EFI_VA_START & ~PUD_MASK) != 0);
160         BUILD_BUG_ON((EFI_VA_END & ~PUD_MASK) != 0);
161
162         p4d_efi = p4d_offset(pgd_efi, EFI_VA_END);
163         p4d_k = p4d_offset(pgd_k, EFI_VA_END);
164         pud_efi = pud_offset(p4d_efi, 0);
165         pud_k = pud_offset(p4d_k, 0);
166
167         num_entries = pud_index(EFI_VA_END);
168         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
169
170         pud_efi = pud_offset(p4d_efi, EFI_VA_START);
171         pud_k = pud_offset(p4d_k, EFI_VA_START);
172
173         num_entries = PTRS_PER_PUD - pud_index(EFI_VA_START);
174         memcpy(pud_efi, pud_k, sizeof(pud_t) * num_entries);
175 }
176
177 /*
178  * Wrapper for slow_virt_to_phys() that handles NULL addresses.
179  */
180 static inline phys_addr_t
181 virt_to_phys_or_null_size(void *va, unsigned long size)
182 {
183         bool bad_size;
184
185         if (!va)
186                 return 0;
187
188         if (virt_addr_valid(va))
189                 return virt_to_phys(va);
190
191         /*
192          * A fully aligned variable on the stack is guaranteed not to
193          * cross a page bounary. Try to catch strings on the stack by
194          * checking that 'size' is a power of two.
195          */
196         bad_size = size > PAGE_SIZE || !is_power_of_2(size);
197
198         WARN_ON(!IS_ALIGNED((unsigned long)va, size) || bad_size);
199
200         return slow_virt_to_phys(va);
201 }
202
203 #define virt_to_phys_or_null(addr)                              \
204         virt_to_phys_or_null_size((addr), sizeof(*(addr)))
205
206 int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages)
207 {
208         unsigned long pfn, text, pf;
209         struct page *page;
210         unsigned npages;
211         pgd_t *pgd = efi_mm.pgd;
212
213         if (efi_have_uv1_memmap())
214                 return 0;
215
216         /*
217          * It can happen that the physical address of new_memmap lands in memory
218          * which is not mapped in the EFI page table. Therefore we need to go
219          * and ident-map those pages containing the map before calling
220          * phys_efi_set_virtual_address_map().
221          */
222         pfn = pa_memmap >> PAGE_SHIFT;
223         pf = _PAGE_NX | _PAGE_RW | _PAGE_ENC;
224         if (kernel_map_pages_in_pgd(pgd, pfn, pa_memmap, num_pages, pf)) {
225                 pr_err("Error ident-mapping new memmap (0x%lx)!\n", pa_memmap);
226                 return 1;
227         }
228
229         /*
230          * Certain firmware versions are way too sentimential and still believe
231          * they are exclusive and unquestionable owners of the first physical page,
232          * even though they explicitly mark it as EFI_CONVENTIONAL_MEMORY
233          * (but then write-access it later during SetVirtualAddressMap()).
234          *
235          * Create a 1:1 mapping for this page, to avoid triple faults during early
236          * boot with such firmware. We are free to hand this page to the BIOS,
237          * as trim_bios_range() will reserve the first page and isolate it away
238          * from memory allocators anyway.
239          */
240         if (kernel_map_pages_in_pgd(pgd, 0x0, 0x0, 1, pf)) {
241                 pr_err("Failed to create 1:1 mapping for the first page!\n");
242                 return 1;
243         }
244
245         /*
246          * When making calls to the firmware everything needs to be 1:1
247          * mapped and addressable with 32-bit pointers. Map the kernel
248          * text and allocate a new stack because we can't rely on the
249          * stack pointer being < 4GB.
250          */
251         if (!efi_is_mixed())
252                 return 0;
253
254         page = alloc_page(GFP_KERNEL|__GFP_DMA32);
255         if (!page) {
256                 pr_err("Unable to allocate EFI runtime stack < 4GB\n");
257                 return 1;
258         }
259
260         efi_scratch.phys_stack = page_to_phys(page + 1); /* stack grows down */
261
262         npages = (__end_rodata_aligned - _text) >> PAGE_SHIFT;
263         text = __pa(_text);
264         pfn = text >> PAGE_SHIFT;
265
266         pf = _PAGE_ENC;
267         if (kernel_map_pages_in_pgd(pgd, pfn, text, npages, pf)) {
268                 pr_err("Failed to map kernel text 1:1\n");
269                 return 1;
270         }
271
272         return 0;
273 }
274
275 static void __init __map_region(efi_memory_desc_t *md, u64 va)
276 {
277         unsigned long flags = _PAGE_RW;
278         unsigned long pfn;
279         pgd_t *pgd = efi_mm.pgd;
280
281         /*
282          * EFI_RUNTIME_SERVICES_CODE regions typically cover PE/COFF
283          * executable images in memory that consist of both R-X and
284          * RW- sections, so we cannot apply read-only or non-exec
285          * permissions just yet. However, modern EFI systems provide
286          * a memory attributes table that describes those sections
287          * with the appropriate restricted permissions, which are
288          * applied in efi_runtime_update_mappings() below. All other
289          * regions can be mapped non-executable at this point, with
290          * the exception of boot services code regions, but those will
291          * be unmapped again entirely in efi_free_boot_services().
292          */
293         if (md->type != EFI_BOOT_SERVICES_CODE &&
294             md->type != EFI_RUNTIME_SERVICES_CODE)
295                 flags |= _PAGE_NX;
296
297         if (!(md->attribute & EFI_MEMORY_WB))
298                 flags |= _PAGE_PCD;
299
300         if (sev_active() && md->type != EFI_MEMORY_MAPPED_IO)
301                 flags |= _PAGE_ENC;
302
303         pfn = md->phys_addr >> PAGE_SHIFT;
304         if (kernel_map_pages_in_pgd(pgd, pfn, va, md->num_pages, flags))
305                 pr_warn("Error mapping PA 0x%llx -> VA 0x%llx!\n",
306                            md->phys_addr, va);
307 }
308
309 void __init efi_map_region(efi_memory_desc_t *md)
310 {
311         unsigned long size = md->num_pages << PAGE_SHIFT;
312         u64 pa = md->phys_addr;
313
314         if (efi_have_uv1_memmap())
315                 return old_map_region(md);
316
317         /*
318          * Make sure the 1:1 mappings are present as a catch-all for b0rked
319          * firmware which doesn't update all internal pointers after switching
320          * to virtual mode and would otherwise crap on us.
321          */
322         __map_region(md, md->phys_addr);
323
324         /*
325          * Enforce the 1:1 mapping as the default virtual address when
326          * booting in EFI mixed mode, because even though we may be
327          * running a 64-bit kernel, the firmware may only be 32-bit.
328          */
329         if (efi_is_mixed()) {
330                 md->virt_addr = md->phys_addr;
331                 return;
332         }
333
334         efi_va -= size;
335
336         /* Is PA 2M-aligned? */
337         if (!(pa & (PMD_SIZE - 1))) {
338                 efi_va &= PMD_MASK;
339         } else {
340                 u64 pa_offset = pa & (PMD_SIZE - 1);
341                 u64 prev_va = efi_va;
342
343                 /* get us the same offset within this 2M page */
344                 efi_va = (efi_va & PMD_MASK) + pa_offset;
345
346                 if (efi_va > prev_va)
347                         efi_va -= PMD_SIZE;
348         }
349
350         if (efi_va < EFI_VA_END) {
351                 pr_warn(FW_WARN "VA address range overflow!\n");
352                 return;
353         }
354
355         /* Do the VA map */
356         __map_region(md, efi_va);
357         md->virt_addr = efi_va;
358 }
359
360 /*
361  * kexec kernel will use efi_map_region_fixed to map efi runtime memory ranges.
362  * md->virt_addr is the original virtual address which had been mapped in kexec
363  * 1st kernel.
364  */
365 void __init efi_map_region_fixed(efi_memory_desc_t *md)
366 {
367         __map_region(md, md->phys_addr);
368         __map_region(md, md->virt_addr);
369 }
370
371 void __init parse_efi_setup(u64 phys_addr, u32 data_len)
372 {
373         efi_setup = phys_addr + sizeof(struct setup_data);
374 }
375
376 static int __init efi_update_mappings(efi_memory_desc_t *md, unsigned long pf)
377 {
378         unsigned long pfn;
379         pgd_t *pgd = efi_mm.pgd;
380         int err1, err2;
381
382         /* Update the 1:1 mapping */
383         pfn = md->phys_addr >> PAGE_SHIFT;
384         err1 = kernel_map_pages_in_pgd(pgd, pfn, md->phys_addr, md->num_pages, pf);
385         if (err1) {
386                 pr_err("Error while updating 1:1 mapping PA 0x%llx -> VA 0x%llx!\n",
387                            md->phys_addr, md->virt_addr);
388         }
389
390         err2 = kernel_map_pages_in_pgd(pgd, pfn, md->virt_addr, md->num_pages, pf);
391         if (err2) {
392                 pr_err("Error while updating VA mapping PA 0x%llx -> VA 0x%llx!\n",
393                            md->phys_addr, md->virt_addr);
394         }
395
396         return err1 || err2;
397 }
398
399 static int __init efi_update_mem_attr(struct mm_struct *mm, efi_memory_desc_t *md)
400 {
401         unsigned long pf = 0;
402
403         if (md->attribute & EFI_MEMORY_XP)
404                 pf |= _PAGE_NX;
405
406         if (!(md->attribute & EFI_MEMORY_RO))
407                 pf |= _PAGE_RW;
408
409         if (sev_active())
410                 pf |= _PAGE_ENC;
411
412         return efi_update_mappings(md, pf);
413 }
414
415 void __init efi_runtime_update_mappings(void)
416 {
417         efi_memory_desc_t *md;
418
419         if (efi_have_uv1_memmap()) {
420                 if (__supported_pte_mask & _PAGE_NX)
421                         runtime_code_page_mkexec();
422                 return;
423         }
424
425         /*
426          * Use the EFI Memory Attribute Table for mapping permissions if it
427          * exists, since it is intended to supersede EFI_PROPERTIES_TABLE.
428          */
429         if (efi_enabled(EFI_MEM_ATTR)) {
430                 efi_memattr_apply_permissions(NULL, efi_update_mem_attr);
431                 return;
432         }
433
434         /*
435          * EFI_MEMORY_ATTRIBUTES_TABLE is intended to replace
436          * EFI_PROPERTIES_TABLE. So, use EFI_PROPERTIES_TABLE to update
437          * permissions only if EFI_MEMORY_ATTRIBUTES_TABLE is not
438          * published by the firmware. Even if we find a buggy implementation of
439          * EFI_MEMORY_ATTRIBUTES_TABLE, don't fall back to
440          * EFI_PROPERTIES_TABLE, because of the same reason.
441          */
442
443         if (!efi_enabled(EFI_NX_PE_DATA))
444                 return;
445
446         for_each_efi_memory_desc(md) {
447                 unsigned long pf = 0;
448
449                 if (!(md->attribute & EFI_MEMORY_RUNTIME))
450                         continue;
451
452                 if (!(md->attribute & EFI_MEMORY_WB))
453                         pf |= _PAGE_PCD;
454
455                 if ((md->attribute & EFI_MEMORY_XP) ||
456                         (md->type == EFI_RUNTIME_SERVICES_DATA))
457                         pf |= _PAGE_NX;
458
459                 if (!(md->attribute & EFI_MEMORY_RO) &&
460                         (md->type != EFI_RUNTIME_SERVICES_CODE))
461                         pf |= _PAGE_RW;
462
463                 if (sev_active())
464                         pf |= _PAGE_ENC;
465
466                 efi_update_mappings(md, pf);
467         }
468 }
469
470 void __init efi_dump_pagetable(void)
471 {
472 #ifdef CONFIG_EFI_PGT_DUMP
473         if (efi_have_uv1_memmap())
474                 ptdump_walk_pgd_level(NULL, &init_mm);
475         else
476                 ptdump_walk_pgd_level(NULL, &efi_mm);
477 #endif
478 }
479
480 /*
481  * Makes the calling thread switch to/from efi_mm context. Can be used
482  * in a kernel thread and user context. Preemption needs to remain disabled
483  * while the EFI-mm is borrowed. mmgrab()/mmdrop() is not used because the mm
484  * can not change under us.
485  * It should be ensured that there are no concurent calls to this function.
486  */
487 void efi_switch_mm(struct mm_struct *mm)
488 {
489         efi_scratch.prev_mm = current->active_mm;
490         current->active_mm = mm;
491         switch_mm(efi_scratch.prev_mm, mm, NULL);
492 }
493
494 static DEFINE_SPINLOCK(efi_runtime_lock);
495
496 /*
497  * DS and ES contain user values.  We need to save them.
498  * The 32-bit EFI code needs a valid DS, ES, and SS.  There's no
499  * need to save the old SS: __KERNEL_DS is always acceptable.
500  */
501 #define __efi_thunk(func, ...)                                          \
502 ({                                                                      \
503         efi_runtime_services_32_t *__rt;                                \
504         unsigned short __ds, __es;                                      \
505         efi_status_t ____s;                                             \
506                                                                         \
507         __rt = (void *)(unsigned long)efi.systab->mixed_mode.runtime;   \
508                                                                         \
509         savesegment(ds, __ds);                                          \
510         savesegment(es, __es);                                          \
511                                                                         \
512         loadsegment(ss, __KERNEL_DS);                                   \
513         loadsegment(ds, __KERNEL_DS);                                   \
514         loadsegment(es, __KERNEL_DS);                                   \
515                                                                         \
516         ____s = efi64_thunk(__rt->func, __VA_ARGS__);                   \
517                                                                         \
518         loadsegment(ds, __ds);                                          \
519         loadsegment(es, __es);                                          \
520                                                                         \
521         ____s ^= (____s & BIT(31)) | (____s & BIT_ULL(31)) << 32;       \
522         ____s;                                                          \
523 })
524
525 /*
526  * Switch to the EFI page tables early so that we can access the 1:1
527  * runtime services mappings which are not mapped in any other page
528  * tables.
529  *
530  * Also, disable interrupts because the IDT points to 64-bit handlers,
531  * which aren't going to function correctly when we switch to 32-bit.
532  */
533 #define efi_thunk(func...)                                              \
534 ({                                                                      \
535         efi_status_t __s;                                               \
536                                                                         \
537         arch_efi_call_virt_setup();                                     \
538                                                                         \
539         __s = __efi_thunk(func);                                        \
540                                                                         \
541         arch_efi_call_virt_teardown();                                  \
542                                                                         \
543         __s;                                                            \
544 })
545
546 static efi_status_t __init __no_sanitize_address
547 efi_thunk_set_virtual_address_map(unsigned long memory_map_size,
548                                   unsigned long descriptor_size,
549                                   u32 descriptor_version,
550                                   efi_memory_desc_t *virtual_map)
551 {
552         efi_status_t status;
553         unsigned long flags;
554
555         efi_sync_low_kernel_mappings();
556         local_irq_save(flags);
557
558         efi_switch_mm(&efi_mm);
559
560         status = __efi_thunk(set_virtual_address_map, memory_map_size,
561                              descriptor_size, descriptor_version, virtual_map);
562
563         efi_switch_mm(efi_scratch.prev_mm);
564         local_irq_restore(flags);
565
566         return status;
567 }
568
569 static efi_status_t efi_thunk_get_time(efi_time_t *tm, efi_time_cap_t *tc)
570 {
571         efi_status_t status;
572         u32 phys_tm, phys_tc;
573         unsigned long flags;
574
575         spin_lock(&rtc_lock);
576         spin_lock_irqsave(&efi_runtime_lock, flags);
577
578         phys_tm = virt_to_phys_or_null(tm);
579         phys_tc = virt_to_phys_or_null(tc);
580
581         status = efi_thunk(get_time, phys_tm, phys_tc);
582
583         spin_unlock_irqrestore(&efi_runtime_lock, flags);
584         spin_unlock(&rtc_lock);
585
586         return status;
587 }
588
589 static efi_status_t efi_thunk_set_time(efi_time_t *tm)
590 {
591         efi_status_t status;
592         u32 phys_tm;
593         unsigned long flags;
594
595         spin_lock(&rtc_lock);
596         spin_lock_irqsave(&efi_runtime_lock, flags);
597
598         phys_tm = virt_to_phys_or_null(tm);
599
600         status = efi_thunk(set_time, phys_tm);
601
602         spin_unlock_irqrestore(&efi_runtime_lock, flags);
603         spin_unlock(&rtc_lock);
604
605         return status;
606 }
607
608 static efi_status_t
609 efi_thunk_get_wakeup_time(efi_bool_t *enabled, efi_bool_t *pending,
610                           efi_time_t *tm)
611 {
612         efi_status_t status;
613         u32 phys_enabled, phys_pending, phys_tm;
614         unsigned long flags;
615
616         spin_lock(&rtc_lock);
617         spin_lock_irqsave(&efi_runtime_lock, flags);
618
619         phys_enabled = virt_to_phys_or_null(enabled);
620         phys_pending = virt_to_phys_or_null(pending);
621         phys_tm = virt_to_phys_or_null(tm);
622
623         status = efi_thunk(get_wakeup_time, phys_enabled,
624                              phys_pending, phys_tm);
625
626         spin_unlock_irqrestore(&efi_runtime_lock, flags);
627         spin_unlock(&rtc_lock);
628
629         return status;
630 }
631
632 static efi_status_t
633 efi_thunk_set_wakeup_time(efi_bool_t enabled, efi_time_t *tm)
634 {
635         efi_status_t status;
636         u32 phys_tm;
637         unsigned long flags;
638
639         spin_lock(&rtc_lock);
640         spin_lock_irqsave(&efi_runtime_lock, flags);
641
642         phys_tm = virt_to_phys_or_null(tm);
643
644         status = efi_thunk(set_wakeup_time, enabled, phys_tm);
645
646         spin_unlock_irqrestore(&efi_runtime_lock, flags);
647         spin_unlock(&rtc_lock);
648
649         return status;
650 }
651
652 static unsigned long efi_name_size(efi_char16_t *name)
653 {
654         return ucs2_strsize(name, EFI_VAR_NAME_LEN) + 1;
655 }
656
657 static efi_status_t
658 efi_thunk_get_variable(efi_char16_t *name, efi_guid_t *vendor,
659                        u32 *attr, unsigned long *data_size, void *data)
660 {
661         efi_status_t status;
662         u32 phys_name, phys_vendor, phys_attr;
663         u32 phys_data_size, phys_data;
664         unsigned long flags;
665
666         spin_lock_irqsave(&efi_runtime_lock, flags);
667
668         phys_data_size = virt_to_phys_or_null(data_size);
669         phys_vendor = virt_to_phys_or_null(vendor);
670         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
671         phys_attr = virt_to_phys_or_null(attr);
672         phys_data = virt_to_phys_or_null_size(data, *data_size);
673
674         status = efi_thunk(get_variable, phys_name, phys_vendor,
675                            phys_attr, phys_data_size, phys_data);
676
677         spin_unlock_irqrestore(&efi_runtime_lock, flags);
678
679         return status;
680 }
681
682 static efi_status_t
683 efi_thunk_set_variable(efi_char16_t *name, efi_guid_t *vendor,
684                        u32 attr, unsigned long data_size, void *data)
685 {
686         u32 phys_name, phys_vendor, phys_data;
687         efi_status_t status;
688         unsigned long flags;
689
690         spin_lock_irqsave(&efi_runtime_lock, flags);
691
692         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
693         phys_vendor = virt_to_phys_or_null(vendor);
694         phys_data = virt_to_phys_or_null_size(data, data_size);
695
696         /* If data_size is > sizeof(u32) we've got problems */
697         status = efi_thunk(set_variable, phys_name, phys_vendor,
698                            attr, data_size, phys_data);
699
700         spin_unlock_irqrestore(&efi_runtime_lock, flags);
701
702         return status;
703 }
704
705 static efi_status_t
706 efi_thunk_set_variable_nonblocking(efi_char16_t *name, efi_guid_t *vendor,
707                                    u32 attr, unsigned long data_size,
708                                    void *data)
709 {
710         u32 phys_name, phys_vendor, phys_data;
711         efi_status_t status;
712         unsigned long flags;
713
714         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
715                 return EFI_NOT_READY;
716
717         phys_name = virt_to_phys_or_null_size(name, efi_name_size(name));
718         phys_vendor = virt_to_phys_or_null(vendor);
719         phys_data = virt_to_phys_or_null_size(data, data_size);
720
721         /* If data_size is > sizeof(u32) we've got problems */
722         status = efi_thunk(set_variable, phys_name, phys_vendor,
723                            attr, data_size, phys_data);
724
725         spin_unlock_irqrestore(&efi_runtime_lock, flags);
726
727         return status;
728 }
729
730 static efi_status_t
731 efi_thunk_get_next_variable(unsigned long *name_size,
732                             efi_char16_t *name,
733                             efi_guid_t *vendor)
734 {
735         efi_status_t status;
736         u32 phys_name_size, phys_name, phys_vendor;
737         unsigned long flags;
738
739         spin_lock_irqsave(&efi_runtime_lock, flags);
740
741         phys_name_size = virt_to_phys_or_null(name_size);
742         phys_vendor = virt_to_phys_or_null(vendor);
743         phys_name = virt_to_phys_or_null_size(name, *name_size);
744
745         status = efi_thunk(get_next_variable, phys_name_size,
746                            phys_name, phys_vendor);
747
748         spin_unlock_irqrestore(&efi_runtime_lock, flags);
749
750         return status;
751 }
752
753 static efi_status_t
754 efi_thunk_get_next_high_mono_count(u32 *count)
755 {
756         efi_status_t status;
757         u32 phys_count;
758         unsigned long flags;
759
760         spin_lock_irqsave(&efi_runtime_lock, flags);
761
762         phys_count = virt_to_phys_or_null(count);
763         status = efi_thunk(get_next_high_mono_count, phys_count);
764
765         spin_unlock_irqrestore(&efi_runtime_lock, flags);
766
767         return status;
768 }
769
770 static void
771 efi_thunk_reset_system(int reset_type, efi_status_t status,
772                        unsigned long data_size, efi_char16_t *data)
773 {
774         u32 phys_data;
775         unsigned long flags;
776
777         spin_lock_irqsave(&efi_runtime_lock, flags);
778
779         phys_data = virt_to_phys_or_null_size(data, data_size);
780
781         efi_thunk(reset_system, reset_type, status, data_size, phys_data);
782
783         spin_unlock_irqrestore(&efi_runtime_lock, flags);
784 }
785
786 static efi_status_t
787 efi_thunk_update_capsule(efi_capsule_header_t **capsules,
788                          unsigned long count, unsigned long sg_list)
789 {
790         /*
791          * To properly support this function we would need to repackage
792          * 'capsules' because the firmware doesn't understand 64-bit
793          * pointers.
794          */
795         return EFI_UNSUPPORTED;
796 }
797
798 static efi_status_t
799 efi_thunk_query_variable_info(u32 attr, u64 *storage_space,
800                               u64 *remaining_space,
801                               u64 *max_variable_size)
802 {
803         efi_status_t status;
804         u32 phys_storage, phys_remaining, phys_max;
805         unsigned long flags;
806
807         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
808                 return EFI_UNSUPPORTED;
809
810         spin_lock_irqsave(&efi_runtime_lock, flags);
811
812         phys_storage = virt_to_phys_or_null(storage_space);
813         phys_remaining = virt_to_phys_or_null(remaining_space);
814         phys_max = virt_to_phys_or_null(max_variable_size);
815
816         status = efi_thunk(query_variable_info, attr, phys_storage,
817                            phys_remaining, phys_max);
818
819         spin_unlock_irqrestore(&efi_runtime_lock, flags);
820
821         return status;
822 }
823
824 static efi_status_t
825 efi_thunk_query_variable_info_nonblocking(u32 attr, u64 *storage_space,
826                                           u64 *remaining_space,
827                                           u64 *max_variable_size)
828 {
829         efi_status_t status;
830         u32 phys_storage, phys_remaining, phys_max;
831         unsigned long flags;
832
833         if (efi.runtime_version < EFI_2_00_SYSTEM_TABLE_REVISION)
834                 return EFI_UNSUPPORTED;
835
836         if (!spin_trylock_irqsave(&efi_runtime_lock, flags))
837                 return EFI_NOT_READY;
838
839         phys_storage = virt_to_phys_or_null(storage_space);
840         phys_remaining = virt_to_phys_or_null(remaining_space);
841         phys_max = virt_to_phys_or_null(max_variable_size);
842
843         status = efi_thunk(query_variable_info, attr, phys_storage,
844                            phys_remaining, phys_max);
845
846         spin_unlock_irqrestore(&efi_runtime_lock, flags);
847
848         return status;
849 }
850
851 static efi_status_t
852 efi_thunk_query_capsule_caps(efi_capsule_header_t **capsules,
853                              unsigned long count, u64 *max_size,
854                              int *reset_type)
855 {
856         /*
857          * To properly support this function we would need to repackage
858          * 'capsules' because the firmware doesn't understand 64-bit
859          * pointers.
860          */
861         return EFI_UNSUPPORTED;
862 }
863
864 void __init efi_thunk_runtime_setup(void)
865 {
866         if (!IS_ENABLED(CONFIG_EFI_MIXED))
867                 return;
868
869         efi.get_time = efi_thunk_get_time;
870         efi.set_time = efi_thunk_set_time;
871         efi.get_wakeup_time = efi_thunk_get_wakeup_time;
872         efi.set_wakeup_time = efi_thunk_set_wakeup_time;
873         efi.get_variable = efi_thunk_get_variable;
874         efi.get_next_variable = efi_thunk_get_next_variable;
875         efi.set_variable = efi_thunk_set_variable;
876         efi.set_variable_nonblocking = efi_thunk_set_variable_nonblocking;
877         efi.get_next_high_mono_count = efi_thunk_get_next_high_mono_count;
878         efi.reset_system = efi_thunk_reset_system;
879         efi.query_variable_info = efi_thunk_query_variable_info;
880         efi.query_variable_info_nonblocking = efi_thunk_query_variable_info_nonblocking;
881         efi.update_capsule = efi_thunk_update_capsule;
882         efi.query_capsule_caps = efi_thunk_query_capsule_caps;
883 }
884
885 efi_status_t __init __no_sanitize_address
886 efi_set_virtual_address_map(unsigned long memory_map_size,
887                             unsigned long descriptor_size,
888                             u32 descriptor_version,
889                             efi_memory_desc_t *virtual_map)
890 {
891         efi_status_t status;
892         unsigned long flags;
893         pgd_t *save_pgd = NULL;
894
895         if (efi_is_mixed())
896                 return efi_thunk_set_virtual_address_map(memory_map_size,
897                                                          descriptor_size,
898                                                          descriptor_version,
899                                                          virtual_map);
900
901         if (efi_have_uv1_memmap()) {
902                 save_pgd = efi_uv1_memmap_phys_prolog();
903                 if (!save_pgd)
904                         return EFI_ABORTED;
905         } else {
906                 efi_switch_mm(&efi_mm);
907         }
908
909         kernel_fpu_begin();
910
911         /* Disable interrupts around EFI calls: */
912         local_irq_save(flags);
913         status = efi_call(efi.systab->runtime->set_virtual_address_map,
914                           memory_map_size, descriptor_size,
915                           descriptor_version, virtual_map);
916         local_irq_restore(flags);
917
918         kernel_fpu_end();
919
920         if (save_pgd)
921                 efi_uv1_memmap_phys_epilog(save_pgd);
922         else
923                 efi_switch_mm(efi_scratch.prev_mm);
924
925         return status;
926 }