1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _ASM_X86_EFI_H
3 #define _ASM_X86_EFI_H
4
5 #include <asm/fpu/api.h>
6 #include <asm/processor-flags.h>
7 #include <asm/tlb.h>
8 #include <asm/nospec-branch.h>
9 #include <asm/mmu_context.h>
10 #include <asm/ibt.h>
11 #include <linux/build_bug.h>
12 #include <linux/kernel.h>
13 #include <linux/pgtable.h>
14
15 extern unsigned long efi_fw_vendor, efi_config_table;
16 extern unsigned long efi_mixed_mode_stack_pa;
17
18 /*
19 * We map the EFI regions needed for runtime services non-contiguously,
20 * with preserved alignment on virtual addresses starting from -4G down
21 * for a total max space of 64G. This way, we provide for stable runtime
22 * services addresses across kernels so that a kexec'd kernel can still
23 * use them.
24 *
25 * This is the main reason why we're doing stable VA mappings for RT
26 * services.
27 */
28
29 #define EFI32_LOADER_SIGNATURE "EL32"
30 #define EFI64_LOADER_SIGNATURE "EL64"
31
32 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
33
34 /*
35 * The EFI services are called through variadic functions in many cases. These
36 * functions are implemented in assembler and support only a fixed number of
37 * arguments. The macros below allows us to check at build time that we don't
38 * try to call them with too many arguments.
39 *
40 * __efi_nargs() will return the number of arguments if it is 7 or less, and
41 * cause a BUILD_BUG otherwise. The limitations of the C preprocessor make it
42 * impossible to calculate the exact number of arguments beyond some
43 * pre-defined limit. The maximum number of arguments currently supported by
44 * any of the thunks is 7, so this is good enough for now and can be extended
45 * in the obvious way if we ever need more.
46 */
47
48 #define __efi_nargs(...) __efi_nargs_(__VA_ARGS__)
49 #define __efi_nargs_(...) __efi_nargs__(0, ##__VA_ARGS__, \
50 __efi_arg_sentinel(9), __efi_arg_sentinel(8), \
51 __efi_arg_sentinel(7), __efi_arg_sentinel(6), \
52 __efi_arg_sentinel(5), __efi_arg_sentinel(4), \
53 __efi_arg_sentinel(3), __efi_arg_sentinel(2), \
54 __efi_arg_sentinel(1), __efi_arg_sentinel(0))
55 #define __efi_nargs__(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, ...) \
56 __take_second_arg(n, \
57 ({ BUILD_BUG_ON_MSG(1, "__efi_nargs limit exceeded"); 10; }))
58 #define __efi_arg_sentinel(n) , n
59
60 /*
61 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
62 * represents more than n arguments.
63 */
64
65 #define __efi_nargs_check(f, n, ...) \
66 __efi_nargs_check_(f, __efi_nargs(__VA_ARGS__), n)
67 #define __efi_nargs_check_(f, p, n) __efi_nargs_check__(f, p, n)
68 #define __efi_nargs_check__(f, p, n) ({ \
69 BUILD_BUG_ON_MSG( \
70 (p) > (n), \
71 #f " called with too many arguments (" #p ">" #n ")"); \
72 })
73
efi_fpu_begin(void)74 static inline void efi_fpu_begin(void)
75 {
76 /*
77 * The UEFI calling convention (UEFI spec 2.3.2 and 2.3.4) requires
78 * that FCW and MXCSR (64-bit) must be initialized prior to calling
79 * UEFI code. (Oddly the spec does not require that the FPU stack
80 * be empty.)
81 */
82 kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR);
83 }
84
efi_fpu_end(void)85 static inline void efi_fpu_end(void)
86 {
87 kernel_fpu_end();
88 }
89
90 #ifdef CONFIG_X86_32
91 #define arch_efi_call_virt_setup() \
92 ({ \
93 efi_fpu_begin(); \
94 firmware_restrict_branch_speculation_start(); \
95 })
96
97 #define arch_efi_call_virt_teardown() \
98 ({ \
99 firmware_restrict_branch_speculation_end(); \
100 efi_fpu_end(); \
101 })
102
103 #else /* !CONFIG_X86_32 */
104
105 #define EFI_LOADER_SIGNATURE "EL64"
106
107 extern asmlinkage u64 __efi_call(void *fp, ...);
108
109 extern bool efi_disable_ibt_for_runtime;
110
111 #define efi_call(...) ({ \
112 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \
113 __efi_call(__VA_ARGS__); \
114 })
115
116 #define arch_efi_call_virt_setup() \
117 ({ \
118 efi_sync_low_kernel_mappings(); \
119 efi_fpu_begin(); \
120 firmware_restrict_branch_speculation_start(); \
121 efi_enter_mm(); \
122 })
123
124 #undef arch_efi_call_virt
125 #define arch_efi_call_virt(p, f, args...) ({ \
126 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \
127 ret = efi_call((void *)p->f, args); \
128 ibt_restore(ibt); \
129 ret; \
130 })
131
132 #define arch_efi_call_virt_teardown() \
133 ({ \
134 efi_leave_mm(); \
135 firmware_restrict_branch_speculation_end(); \
136 efi_fpu_end(); \
137 })
138
139 #ifdef CONFIG_KASAN
140 /*
141 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
142 * only in kernel binary. Since the EFI stub linked into a separate binary it
143 * doesn't have __memset(). So we should use standard memset from
144 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
145 */
146 #undef memcpy
147 #undef memset
148 #undef memmove
149 #endif
150
151 #endif /* CONFIG_X86_32 */
152
153 extern int __init efi_memblock_x86_reserve_range(void);
154 extern void __init efi_print_memmap(void);
155 extern void __init efi_map_region(efi_memory_desc_t *md);
156 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
157 extern void efi_sync_low_kernel_mappings(void);
158 extern int __init efi_alloc_page_tables(void);
159 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
160 extern void __init efi_runtime_update_mappings(void);
161 extern void __init efi_dump_pagetable(void);
162 extern void __init efi_apply_memmap_quirks(void);
163 extern int __init efi_reuse_config(u64 tables, int nr_tables);
164 extern void efi_delete_dummy_variable(void);
165 extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
166 extern void efi_free_boot_services(void);
167
168 void efi_enter_mm(void);
169 void efi_leave_mm(void);
170
171 /* kexec external ABI */
172 struct efi_setup_data {
173 u64 fw_vendor;
174 u64 __unused;
175 u64 tables;
176 u64 smbios;
177 u64 reserved[8];
178 };
179
180 extern u64 efi_setup;
181
182 #ifdef CONFIG_EFI
183 extern u64 __efi64_thunk(u32, ...);
184
185 #define efi64_thunk(...) ({ \
186 u64 __pad[3]; /* must have space for 3 args on the stack */ \
187 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \
188 __efi64_thunk(__VA_ARGS__, __pad); \
189 })
190
efi_is_mixed(void)191 static inline bool efi_is_mixed(void)
192 {
193 if (!IS_ENABLED(CONFIG_EFI_MIXED))
194 return false;
195 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
196 }
197
efi_runtime_supported(void)198 static inline bool efi_runtime_supported(void)
199 {
200 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
201 return true;
202
203 return IS_ENABLED(CONFIG_EFI_MIXED);
204 }
205
206 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
207
208 extern void efi_thunk_runtime_setup(void);
209 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
210 unsigned long descriptor_size,
211 u32 descriptor_version,
212 efi_memory_desc_t *virtual_map,
213 unsigned long systab_phys);
214
215 /* arch specific definitions used by the stub code */
216
217 #ifdef CONFIG_EFI_MIXED
218
219 #define ARCH_HAS_EFISTUB_WRAPPERS
220
efi_is_64bit(void)221 static inline bool efi_is_64bit(void)
222 {
223 extern const bool efi_is64;
224
225 return efi_is64;
226 }
227
efi_is_native(void)228 static inline bool efi_is_native(void)
229 {
230 return efi_is_64bit();
231 }
232
233 #define efi_table_attr(inst, attr) \
234 (efi_is_native() ? (inst)->attr \
235 : efi_mixed_table_attr((inst), attr))
236
237 #define efi_mixed_table_attr(inst, attr) \
238 (__typeof__(inst->attr)) \
239 _Generic(inst->mixed_mode.attr, \
240 u32: (unsigned long)(inst->mixed_mode.attr), \
241 default: (inst->mixed_mode.attr))
242
243 /*
244 * The following macros allow translating arguments if necessary from native to
245 * mixed mode. The use case for this is to initialize the upper 32 bits of
246 * output parameters, and where the 32-bit method requires a 64-bit argument,
247 * which must be split up into two arguments to be thunked properly.
248 *
249 * As examples, the AllocatePool boot service returns the address of the
250 * allocation, but it will not set the high 32 bits of the address. To ensure
251 * that the full 64-bit address is initialized, we zero-init the address before
252 * calling the thunk.
253 *
254 * The FreePages boot service takes a 64-bit physical address even in 32-bit
255 * mode. For the thunk to work correctly, a native 64-bit call of
256 * free_pages(addr, size)
257 * must be translated to
258 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size)
259 * so that the two 32-bit halves of addr get pushed onto the stack separately.
260 */
261
efi64_zero_upper(void * p)262 static inline void *efi64_zero_upper(void *p)
263 {
264 ((u32 *)p)[1] = 0;
265 return p;
266 }
267
efi64_convert_status(efi_status_t status)268 static inline u32 efi64_convert_status(efi_status_t status)
269 {
270 return (u32)(status | (u64)status >> 32);
271 }
272
273 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32
274
275 #define __efi64_argmap_free_pages(addr, size) \
276 ((addr), 0, (size))
277
278 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \
279 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver))
280
281 #define __efi64_argmap_allocate_pool(type, size, buffer) \
282 ((type), (size), efi64_zero_upper(buffer))
283
284 #define __efi64_argmap_create_event(type, tpl, f, c, event) \
285 ((type), (tpl), (f), (c), efi64_zero_upper(event))
286
287 #define __efi64_argmap_set_timer(event, type, time) \
288 ((event), (type), lower_32_bits(time), upper_32_bits(time))
289
290 #define __efi64_argmap_wait_for_event(num, event, index) \
291 ((num), (event), efi64_zero_upper(index))
292
293 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \
294 ((handle), (protocol), efi64_zero_upper(interface))
295
296 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \
297 ((protocol), (reg), efi64_zero_upper(interface))
298
299 #define __efi64_argmap_locate_device_path(protocol, path, handle) \
300 ((protocol), (path), efi64_zero_upper(handle))
301
302 #define __efi64_argmap_exit(handle, status, size, data) \
303 ((handle), efi64_convert_status(status), (size), (data))
304
305 /* PCI I/O */
306 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \
307 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \
308 efi64_zero_upper(dev), efi64_zero_upper(func))
309
310 /* LoadFile */
311 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \
312 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))
313
314 /* Graphics Output Protocol */
315 #define __efi64_argmap_query_mode(gop, mode, size, info) \
316 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info))
317
318 /* TCG2 protocol */
319 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \
320 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)
321
322 /* DXE services */
323 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
324 (__efi64_split(phys), (desc))
325
326 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
327 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
328
329 /* file protocol */
330 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \
331 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
332 __efi64_split(attr))
333
334 #define __efi64_argmap_set_position(pos) (__efi64_split(pos))
335
336 /* file system protocol */
337 #define __efi64_argmap_open_volume(prot, file) \
338 ((prot), efi64_zero_upper(file))
339
340 /* Memory Attribute Protocol */
341 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
342 ((protocol), __efi64_split(phys), __efi64_split(size), (flags))
343
344 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
345 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
346
347 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
348 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
349
350 /*
351 * The macros below handle the plumbing for the argument mapping. To add a
352 * mapping for a specific EFI method, simply define a macro
353 * __efi64_argmap_<method name>, following the examples above.
354 */
355
356 #define __efi64_thunk_map(inst, func, ...) \
357 efi64_thunk(inst->mixed_mode.func, \
358 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \
359 (__VA_ARGS__)))
360
361 #define __efi64_argmap(mapped, args) \
362 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args)
363 #define __efi64_argmap__0(mapped, args) __efi_eval mapped
364 #define __efi64_argmap__1(mapped, args) __efi_eval args
365
366 #define __efi_eat(...)
367 #define __efi_eval(...) __VA_ARGS__
368
__efi64_widen_efi_status(u64 status)369 static inline efi_status_t __efi64_widen_efi_status(u64 status)
370 {
371 /* use rotate to move the value of bit #31 into position #63 */
372 return ror64(rol32(status, 1), 1);
373 }
374
375 /* The macro below handles dispatching via the thunk if needed */
376
377 #define efi_fn_call(inst, func, ...) \
378 (efi_is_native() ? (inst)->func(__VA_ARGS__) \
379 : efi_mixed_call((inst), func, ##__VA_ARGS__))
380
381 #define efi_mixed_call(inst, func, ...) \
382 _Generic(inst->func(__VA_ARGS__), \
383 efi_status_t: \
384 __efi64_widen_efi_status( \
385 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \
386 u64: ({ BUILD_BUG(); ULONG_MAX; }), \
387 default: \
388 (__typeof__(inst->func(__VA_ARGS__))) \
389 __efi64_thunk_map(inst, func, ##__VA_ARGS__))
390
391 #else /* CONFIG_EFI_MIXED */
392
efi_is_64bit(void)393 static inline bool efi_is_64bit(void)
394 {
395 return IS_ENABLED(CONFIG_X86_64);
396 }
397
398 #endif /* CONFIG_EFI_MIXED */
399
400 extern bool efi_reboot_required(void);
401 extern bool efi_is_table_address(unsigned long phys_addr);
402
403 extern void efi_reserve_boot_services(void);
404 #else
parse_efi_setup(u64 phys_addr,u32 data_len)405 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
efi_reboot_required(void)406 static inline bool efi_reboot_required(void)
407 {
408 return false;
409 }
efi_is_table_address(unsigned long phys_addr)410 static inline bool efi_is_table_address(unsigned long phys_addr)
411 {
412 return false;
413 }
efi_reserve_boot_services(void)414 static inline void efi_reserve_boot_services(void)
415 {
416 }
417 #endif /* CONFIG_EFI */
418
419 #ifdef CONFIG_EFI_FAKE_MEMMAP
420 extern void __init efi_fake_memmap_early(void);
421 extern void __init efi_fake_memmap(void);
422 #else
efi_fake_memmap_early(void)423 static inline void efi_fake_memmap_early(void)
424 {
425 }
426
efi_fake_memmap(void)427 static inline void efi_fake_memmap(void)
428 {
429 }
430 #endif
431
432 extern int __init efi_memmap_alloc(unsigned int num_entries,
433 struct efi_memory_map_data *data);
434 extern void __efi_memmap_free(u64 phys, unsigned long size,
435 unsigned long flags);
436 #define __efi_memmap_free __efi_memmap_free
437
438 extern int __init efi_memmap_install(struct efi_memory_map_data *data);
439 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
440 struct range *range);
441 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
442 void *buf, struct efi_mem_range *mem);
443
444 #define arch_ima_efi_boot_mode \
445 ({ extern struct boot_params boot_params; boot_params.secure_boot; })
446
447 #ifdef CONFIG_EFI_RUNTIME_MAP
448 int efi_get_runtime_map_size(void);
449 int efi_get_runtime_map_desc_size(void);
450 int efi_runtime_map_copy(void *buf, size_t bufsz);
451 #else
efi_get_runtime_map_size(void)452 static inline int efi_get_runtime_map_size(void)
453 {
454 return 0;
455 }
456
efi_get_runtime_map_desc_size(void)457 static inline int efi_get_runtime_map_desc_size(void)
458 {
459 return 0;
460 }
461
efi_runtime_map_copy(void * buf,size_t bufsz)462 static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
463 {
464 return 0;
465 }
466
467 #endif
468
469 #endif /* _ASM_X86_EFI_H */
470