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
efi_fpu_begin(void)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
efi_fpu_end(void)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 /* kexec external ABI */
147 struct efi_setup_data {
148 u64 fw_vendor;
149 u64 __unused;
150 u64 tables;
151 u64 smbios;
152 u64 reserved[8];
153 };
154
155 extern u64 efi_setup;
156
157 #ifdef CONFIG_EFI
158 extern u64 __efi64_thunk(u32, ...);
159
160 #define efi64_thunk(...) ({ \
161 u64 __pad[3]; /* must have space for 3 args on the stack */ \
162 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \
163 __efi64_thunk(__VA_ARGS__, __pad); \
164 })
165
efi_is_mixed(void)166 static inline bool efi_is_mixed(void)
167 {
168 if (!IS_ENABLED(CONFIG_EFI_MIXED))
169 return false;
170 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
171 }
172
efi_runtime_supported(void)173 static inline bool efi_runtime_supported(void)
174 {
175 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
176 return true;
177
178 return IS_ENABLED(CONFIG_EFI_MIXED);
179 }
180
181 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
182
183 extern void efi_thunk_runtime_setup(void);
184 efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
185 unsigned long descriptor_size,
186 u32 descriptor_version,
187 efi_memory_desc_t *virtual_map,
188 unsigned long systab_phys);
189
190 /* arch specific definitions used by the stub code */
191
192 #ifdef CONFIG_EFI_MIXED
193
194 #define EFI_ALLOC_LIMIT (efi_is_64bit() ? ULONG_MAX : U32_MAX)
195
196 #define ARCH_HAS_EFISTUB_WRAPPERS
197
efi_is_64bit(void)198 static inline bool efi_is_64bit(void)
199 {
200 extern const bool efi_is64;
201
202 return efi_is64;
203 }
204
efi_is_native(void)205 static inline bool efi_is_native(void)
206 {
207 return efi_is_64bit();
208 }
209
210 #define efi_table_attr(inst, attr) \
211 (efi_is_native() ? (inst)->attr \
212 : efi_mixed_table_attr((inst), attr))
213
214 #define efi_mixed_table_attr(inst, attr) \
215 (__typeof__(inst->attr)) \
216 _Generic(inst->mixed_mode.attr, \
217 u32: (unsigned long)(inst->mixed_mode.attr), \
218 default: (inst->mixed_mode.attr))
219
220 /*
221 * The following macros allow translating arguments if necessary from native to
222 * mixed mode. The use case for this is to initialize the upper 32 bits of
223 * output parameters, and where the 32-bit method requires a 64-bit argument,
224 * which must be split up into two arguments to be thunked properly.
225 *
226 * As examples, the AllocatePool boot service returns the address of the
227 * allocation, but it will not set the high 32 bits of the address. To ensure
228 * that the full 64-bit address is initialized, we zero-init the address before
229 * calling the thunk.
230 *
231 * The FreePages boot service takes a 64-bit physical address even in 32-bit
232 * mode. For the thunk to work correctly, a native 64-bit call of
233 * free_pages(addr, size)
234 * must be translated to
235 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size)
236 * so that the two 32-bit halves of addr get pushed onto the stack separately.
237 */
238
efi64_zero_upper(void * p)239 static inline void *efi64_zero_upper(void *p)
240 {
241 ((u32 *)p)[1] = 0;
242 return p;
243 }
244
efi64_convert_status(efi_status_t status)245 static inline u32 efi64_convert_status(efi_status_t status)
246 {
247 return (u32)(status | (u64)status >> 32);
248 }
249
250 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32
251
252 #define __efi64_argmap_free_pages(addr, size) \
253 ((addr), 0, (size))
254
255 #define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \
256 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver))
257
258 #define __efi64_argmap_allocate_pool(type, size, buffer) \
259 ((type), (size), efi64_zero_upper(buffer))
260
261 #define __efi64_argmap_create_event(type, tpl, f, c, event) \
262 ((type), (tpl), (f), (c), efi64_zero_upper(event))
263
264 #define __efi64_argmap_set_timer(event, type, time) \
265 ((event), (type), lower_32_bits(time), upper_32_bits(time))
266
267 #define __efi64_argmap_wait_for_event(num, event, index) \
268 ((num), (event), efi64_zero_upper(index))
269
270 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \
271 ((handle), (protocol), efi64_zero_upper(interface))
272
273 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \
274 ((protocol), (reg), efi64_zero_upper(interface))
275
276 #define __efi64_argmap_locate_device_path(protocol, path, handle) \
277 ((protocol), (path), efi64_zero_upper(handle))
278
279 #define __efi64_argmap_exit(handle, status, size, data) \
280 ((handle), efi64_convert_status(status), (size), (data))
281
282 /* PCI I/O */
283 #define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \
284 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \
285 efi64_zero_upper(dev), efi64_zero_upper(func))
286
287 /* LoadFile */
288 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \
289 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))
290
291 /* Graphics Output Protocol */
292 #define __efi64_argmap_query_mode(gop, mode, size, info) \
293 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info))
294
295 /* TCG2 protocol */
296 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \
297 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)
298
299 /* DXE services */
300 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
301 (__efi64_split(phys), (desc))
302
303 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
304 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
305
306 /* file protocol */
307 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \
308 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
309 __efi64_split(attr))
310
311 #define __efi64_argmap_set_position(pos) (__efi64_split(pos))
312
313 /* file system protocol */
314 #define __efi64_argmap_open_volume(prot, file) \
315 ((prot), efi64_zero_upper(file))
316
317 /* Memory Attribute Protocol */
318 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
319 ((protocol), __efi64_split(phys), __efi64_split(size), (flags))
320
321 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
322 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
323
324 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
325 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
326
327 /*
328 * The macros below handle the plumbing for the argument mapping. To add a
329 * mapping for a specific EFI method, simply define a macro
330 * __efi64_argmap_<method name>, following the examples above.
331 */
332
333 #define __efi64_thunk_map(inst, func, ...) \
334 efi64_thunk(inst->mixed_mode.func, \
335 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \
336 (__VA_ARGS__)))
337
338 #define __efi64_argmap(mapped, args) \
339 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args)
340 #define __efi64_argmap__0(mapped, args) __efi_eval mapped
341 #define __efi64_argmap__1(mapped, args) __efi_eval args
342
343 #define __efi_eat(...)
344 #define __efi_eval(...) __VA_ARGS__
345
__efi64_widen_efi_status(u64 status)346 static inline efi_status_t __efi64_widen_efi_status(u64 status)
347 {
348 /* use rotate to move the value of bit #31 into position #63 */
349 return ror64(rol32(status, 1), 1);
350 }
351
352 /* The macro below handles dispatching via the thunk if needed */
353
354 #define efi_fn_call(inst, func, ...) \
355 (efi_is_native() ? (inst)->func(__VA_ARGS__) \
356 : efi_mixed_call((inst), func, ##__VA_ARGS__))
357
358 #define efi_mixed_call(inst, func, ...) \
359 _Generic(inst->func(__VA_ARGS__), \
360 efi_status_t: \
361 __efi64_widen_efi_status( \
362 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \
363 u64: ({ BUILD_BUG(); ULONG_MAX; }), \
364 default: \
365 (__typeof__(inst->func(__VA_ARGS__))) \
366 __efi64_thunk_map(inst, func, ##__VA_ARGS__))
367
368 #else /* CONFIG_EFI_MIXED */
369
efi_is_64bit(void)370 static inline bool efi_is_64bit(void)
371 {
372 return IS_ENABLED(CONFIG_X86_64);
373 }
374
375 #endif /* CONFIG_EFI_MIXED */
376
377 extern bool efi_reboot_required(void);
378 extern bool efi_is_table_address(unsigned long phys_addr);
379
380 extern void efi_reserve_boot_services(void);
381 #else
parse_efi_setup(u64 phys_addr,u32 data_len)382 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
efi_reboot_required(void)383 static inline bool efi_reboot_required(void)
384 {
385 return false;
386 }
efi_is_table_address(unsigned long phys_addr)387 static inline bool efi_is_table_address(unsigned long phys_addr)
388 {
389 return false;
390 }
efi_reserve_boot_services(void)391 static inline void efi_reserve_boot_services(void)
392 {
393 }
394 #endif /* CONFIG_EFI */
395
396 #ifdef CONFIG_EFI_FAKE_MEMMAP
397 extern void __init efi_fake_memmap_early(void);
398 extern void __init efi_fake_memmap(void);
399 #else
efi_fake_memmap_early(void)400 static inline void efi_fake_memmap_early(void)
401 {
402 }
403
efi_fake_memmap(void)404 static inline void efi_fake_memmap(void)
405 {
406 }
407 #endif
408
409 extern int __init efi_memmap_alloc(unsigned int num_entries,
410 struct efi_memory_map_data *data);
411 extern void __efi_memmap_free(u64 phys, unsigned long size,
412 unsigned long flags);
413
414 extern int __init efi_memmap_install(struct efi_memory_map_data *data);
415 extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
416 struct range *range);
417 extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
418 void *buf, struct efi_mem_range *mem);
419
420 #define arch_ima_efi_boot_mode \
421 ({ extern struct boot_params boot_params; boot_params.secure_boot; })
422
423 #ifdef CONFIG_EFI_RUNTIME_MAP
424 int efi_get_runtime_map_size(void);
425 int efi_get_runtime_map_desc_size(void);
426 int efi_runtime_map_copy(void *buf, size_t bufsz);
427 #else
efi_get_runtime_map_size(void)428 static inline int efi_get_runtime_map_size(void)
429 {
430 return 0;
431 }
432
efi_get_runtime_map_desc_size(void)433 static inline int efi_get_runtime_map_desc_size(void)
434 {
435 return 0;
436 }
437
efi_runtime_map_copy(void * buf,size_t bufsz)438 static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
439 {
440 return 0;
441 }
442
443 #endif
444
445 #endif /* _ASM_X86_EFI_H */
446