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 #define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE
35
36 /*
37 * The EFI services are called through variadic functions in many cases. These
38 * functions are implemented in assembler and support only a fixed number of
39 * arguments. The macros below allows us to check at build time that we don't
40 * try to call them with too many arguments.
41 *
42 * __efi_nargs() will return the number of arguments if it is 7 or less, and
43 * cause a BUILD_BUG otherwise. The limitations of the C preprocessor make it
44 * impossible to calculate the exact number of arguments beyond some
45 * pre-defined limit. The maximum number of arguments currently supported by
46 * any of the thunks is 7, so this is good enough for now and can be extended
47 * in the obvious way if we ever need more.
48 */
49
50 #define __efi_nargs(...) __efi_nargs_(__VA_ARGS__)
51 #define __efi_nargs_(...) __efi_nargs__(0, ##__VA_ARGS__, \
52 __efi_arg_sentinel(9), __efi_arg_sentinel(8), \
53 __efi_arg_sentinel(7), __efi_arg_sentinel(6), \
54 __efi_arg_sentinel(5), __efi_arg_sentinel(4), \
55 __efi_arg_sentinel(3), __efi_arg_sentinel(2), \
56 __efi_arg_sentinel(1), __efi_arg_sentinel(0))
57 #define __efi_nargs__(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, ...) \
58 __take_second_arg(n, \
59 ({ BUILD_BUG_ON_MSG(1, "__efi_nargs limit exceeded"); 10; }))
60 #define __efi_arg_sentinel(n) , n
61
62 /*
63 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
64 * represents more than n arguments.
65 */
66
67 #define __efi_nargs_check(f, n, ...) \
68 __efi_nargs_check_(f, __efi_nargs(__VA_ARGS__), n)
69 #define __efi_nargs_check_(f, p, n) __efi_nargs_check__(f, p, n)
70 #define __efi_nargs_check__(f, p, n) ({ \
71 BUILD_BUG_ON_MSG( \
72 (p) > (n), \
73 #f " called with too many arguments (" #p ">" #n ")"); \
74 })
75
76 static inline void efi_fpu_begin(void)
77 {
78 /*
79 * The UEFI calling convention (UEFI spec 2.3.2 and 2.3.4) requires
80 * that FCW and MXCSR (64-bit) must be initialized prior to calling
81 * UEFI code. (Oddly the spec does not require that the FPU stack
82 * be empty.)
83 */
84 kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR);
85 }
86
87 static inline void efi_fpu_end(void)
88 {
89 kernel_fpu_end();
90 }
91
92 #ifdef CONFIG_X86_32
93 #define EFI_X86_KERNEL_ALLOC_LIMIT (SZ_512M - 1)
94 #else /* !CONFIG_X86_32 */
95 #define EFI_X86_KERNEL_ALLOC_LIMIT EFI_ALLOC_LIMIT
96
97 extern asmlinkage u64 __efi_call(void *fp, ...);
98
99 extern bool efi_disable_ibt_for_runtime;
100
101 #define efi_call(...) ({ \
102 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \
103 __efi_call(__VA_ARGS__); \
104 })
105
106 #undef arch_efi_call_virt
107 #define arch_efi_call_virt(p, f, args...) ({ \
108 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \
109 ret = efi_call((void *)p->f, args); \
110 ibt_restore(ibt); \
111 ret; \
112 })
113
114 #ifdef CONFIG_KASAN
115 /*
116 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
117 * only in kernel binary. Since the EFI stub linked into a separate binary it
118 * doesn't have __memset(). So we should use standard memset from
119 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
120 */
121 #undef memcpy
122 #undef memset
123 #undef memmove
124 #endif
125
126 #endif /* CONFIG_X86_32 */
127
128 extern int __init efi_memblock_x86_reserve_range(void);
129 extern void __init efi_print_memmap(void);
130 extern void __init efi_map_region(efi_memory_desc_t *md);
131 extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
132 extern void efi_sync_low_kernel_mappings(void);
133 extern int __init efi_alloc_page_tables(void);
134 extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
135 extern void __init efi_runtime_update_mappings(void);
136 extern void __init efi_dump_pagetable(void);
137 extern void __init efi_apply_memmap_quirks(void);
138 extern int __init efi_reuse_config(u64 tables, int nr_tables);
139 extern void efi_delete_dummy_variable(void);
140 extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
141 extern void efi_free_boot_services(void);
142
143 void arch_efi_call_virt_setup(void);
144 void arch_efi_call_virt_teardown(void);
145
146 extern u64 efi_setup;
147
148 #ifdef CONFIG_EFI
149 extern u64 __efi64_thunk(u32, ...);
150
151 #define efi64_thunk(...) ({ \
152 u64 __pad[3]; /* must have space for 3 args on the stack */ \
153 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \
154 __efi64_thunk(__VA_ARGS__, __pad); \
155 })
156
157 static inline bool efi_is_mixed(void)
158 {
159 if (!IS_ENABLED(CONFIG_EFI_MIXED))
160 return false;
161 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
162 }
163
164 static inline bool efi_runtime_supported(void)
165 {
166 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
167 return true;
168
169 return IS_ENABLED(CONFIG_EFI_MIXED);
170 }
171
172 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
173
174 extern void efi_thunk_runtime_setup(void);
175 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
176 unsigned long descriptor_size,
177 u32 descriptor_version,
178 efi_memory_desc_t *virtual_map,
179 unsigned long systab_phys);
180
181 /* arch specific definitions used by the stub code */
182
183 #ifdef CONFIG_EFI_MIXED
184
185 #define EFI_ALLOC_LIMIT (efi_is_64bit() ? ULONG_MAX : U32_MAX)
186
187 #define ARCH_HAS_EFISTUB_WRAPPERS
188
189 static inline bool efi_is_64bit(void)
190 {
191 extern const bool efi_is64;
192
193 return efi_is64;
194 }
195
196 static inline bool efi_is_native(void)
197 {
198 return efi_is_64bit();
199 }
200
201 #define efi_table_attr(inst, attr) \
202 (efi_is_native() ? (inst)->attr \
203 : efi_mixed_table_attr((inst), attr))
204
205 #define efi_mixed_table_attr(inst, attr) \
206 (__typeof__(inst->attr)) \
207 _Generic(inst->mixed_mode.attr, \
208 u32: (unsigned long)(inst->mixed_mode.attr), \
209 default: (inst->mixed_mode.attr))
210
211 /*
212 * The following macros allow translating arguments if necessary from native to
213 * mixed mode. The use case for this is to initialize the upper 32 bits of
214 * output parameters, and where the 32-bit method requires a 64-bit argument,
215 * which must be split up into two arguments to be thunked properly.
216 *
217 * As examples, the AllocatePool boot service returns the address of the
218 * allocation, but it will not set the high 32 bits of the address. To ensure
219 * that the full 64-bit address is initialized, we zero-init the address before
220 * calling the thunk.
221 *
222 * The FreePages boot service takes a 64-bit physical address even in 32-bit
223 * mode. For the thunk to work correctly, a native 64-bit call of
224 * free_pages(addr, size)
225 * must be translated to
226 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size)
227 * so that the two 32-bit halves of addr get pushed onto the stack separately.
228 */
229
230 static inline void *efi64_zero_upper(void *p)
231 {
232 if (p)
233 ((u32 *)p)[1] = 0;
234 return p;
235 }
236
237 static inline u32 efi64_convert_status(efi_status_t status)
238 {
239 return (u32)(status | (u64)status >> 32);
240 }
241
242 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32
243
244 #define __efi64_argmap_free_pages(addr, size) \
245 ((addr), 0, (size))
246
247 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \
248 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver))
249
250 #define __efi64_argmap_allocate_pool(type, size, buffer) \
251 ((type), (size), efi64_zero_upper(buffer))
252
253 #define __efi64_argmap_create_event(type, tpl, f, c, event) \
254 ((type), (tpl), (f), (c), efi64_zero_upper(event))
255
256 #define __efi64_argmap_set_timer(event, type, time) \
257 ((event), (type), lower_32_bits(time), upper_32_bits(time))
258
259 #define __efi64_argmap_wait_for_event(num, event, index) \
260 ((num), (event), efi64_zero_upper(index))
261
262 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \
263 ((handle), (protocol), efi64_zero_upper(interface))
264
265 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \
266 ((protocol), (reg), efi64_zero_upper(interface))
267
268 #define __efi64_argmap_locate_device_path(protocol, path, handle) \
269 ((protocol), (path), efi64_zero_upper(handle))
270
271 #define __efi64_argmap_exit(handle, status, size, data) \
272 ((handle), efi64_convert_status(status), (size), (data))
273
274 /* PCI I/O */
275 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \
276 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \
277 efi64_zero_upper(dev), efi64_zero_upper(func))
278
279 /* LoadFile */
280 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \
281 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))
282
283 /* Graphics Output Protocol */
284 #define __efi64_argmap_query_mode(gop, mode, size, info) \
285 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info))
286
287 /* TCG2 protocol */
288 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \
289 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)
290
291 /* DXE services */
292 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
293 (__efi64_split(phys), (desc))
294
295 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
296 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
297
298 /* file protocol */
299 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \
300 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
301 __efi64_split(attr))
302
303 #define __efi64_argmap_set_position(pos) (__efi64_split(pos))
304
305 /* file system protocol */
306 #define __efi64_argmap_open_volume(prot, file) \
307 ((prot), efi64_zero_upper(file))
308
309 /* Memory Attribute Protocol */
310 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
311 ((protocol), __efi64_split(phys), __efi64_split(size), (flags))
312
313 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
314 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
315
316 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
317 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
318
319 /* EFI SMBIOS protocol */
320 #define __efi64_argmap_get_next(protocol, smbioshandle, type, record, phandle) \
321 ((protocol), (smbioshandle), (type), efi64_zero_upper(record), \
322 efi64_zero_upper(phandle))
323 /*
324 * The macros below handle the plumbing for the argument mapping. To add a
325 * mapping for a specific EFI method, simply define a macro
326 * __efi64_argmap_<method name>, following the examples above.
327 */
328
329 #define __efi64_thunk_map(inst, func, ...) \
330 efi64_thunk(inst->mixed_mode.func, \
331 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \
332 (__VA_ARGS__)))
333
334 #define __efi64_argmap(mapped, args) \
335 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args)
336 #define __efi64_argmap__0(mapped, args) __efi_eval mapped
337 #define __efi64_argmap__1(mapped, args) __efi_eval args
338
339 #define __efi_eat(...)
340 #define __efi_eval(...) __VA_ARGS__
341
342 static inline efi_status_t __efi64_widen_efi_status(u64 status)
343 {
344 /* use rotate to move the value of bit #31 into position #63 */
345 return ror64(rol32(status, 1), 1);
346 }
347
348 /* The macro below handles dispatching via the thunk if needed */
349
350 #define efi_fn_call(inst, func, ...) \
351 (efi_is_native() ? (inst)->func(__VA_ARGS__) \
352 : efi_mixed_call((inst), func, ##__VA_ARGS__))
353
354 #define efi_mixed_call(inst, func, ...) \
355 _Generic(inst->func(__VA_ARGS__), \
356 efi_status_t: \
357 __efi64_widen_efi_status( \
358 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \
359 u64: ({ BUILD_BUG(); ULONG_MAX; }), \
360 default: \
361 (__typeof__(inst->func(__VA_ARGS__))) \
362 __efi64_thunk_map(inst, func, ##__VA_ARGS__))
363
364 #else /* CONFIG_EFI_MIXED */
365
366 static inline bool efi_is_64bit(void)
367 {
368 return IS_ENABLED(CONFIG_X86_64);
369 }
370
371 #endif /* CONFIG_EFI_MIXED */
372
373 extern bool efi_reboot_required(void);
374 extern bool efi_is_table_address(unsigned long phys_addr);
375
376 extern void efi_reserve_boot_services(void);
377 #else
378 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
379 static inline bool efi_reboot_required(void)
380 {
381 return false;
382 }
383 static inline bool efi_is_table_address(unsigned long phys_addr)
384 {
385 return false;
386 }
387 static inline void efi_reserve_boot_services(void)
388 {
389 }
390 #endif /* CONFIG_EFI */
391
392 extern int __init efi_memmap_alloc(unsigned int num_entries,
393 struct efi_memory_map_data *data);
394
395 extern int __init efi_memmap_install(struct efi_memory_map_data *data);
396 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
397 struct range *range);
398 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
399 void *buf, struct efi_mem_range *mem);
400
401 extern enum efi_secureboot_mode __x86_ima_efi_boot_mode(void);
402
403 #define arch_ima_efi_boot_mode __x86_ima_efi_boot_mode()
404
405 #ifdef CONFIG_EFI_RUNTIME_MAP
406 int efi_get_runtime_map_size(void);
407 int efi_get_runtime_map_desc_size(void);
408 int efi_runtime_map_copy(void *buf, size_t bufsz);
409 #else
410 static inline int efi_get_runtime_map_size(void)
411 {
412 return 0;
413 }
414
415 static inline int efi_get_runtime_map_desc_size(void)
416 {
417 return 0;
418 }
419
420 static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
421 {
422 return 0;
423 }
424
425 #endif
426
427 #endif /* _ASM_X86_EFI_H */
428
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