summaryrefslogtreecommitdiff
path: root/arch/x86/include/asm/efi.h
blob: 481096177500e117d0c955726e779e6537ca063b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_EFI_H
#define _ASM_X86_EFI_H

#include <asm/fpu/api.h>
#include <asm/processor-flags.h>
#include <asm/tlb.h>
#include <asm/nospec-branch.h>
#include <asm/mmu_context.h>
#include <asm/ibt.h>
#include <linux/build_bug.h>
#include <linux/kernel.h>
#include <linux/pgtable.h>

extern unsigned long efi_fw_vendor, efi_config_table;
extern unsigned long efi_mixed_mode_stack_pa;

/*
 * We map the EFI regions needed for runtime services non-contiguously,
 * with preserved alignment on virtual addresses starting from -4G down
 * for a total max space of 64G. This way, we provide for stable runtime
 * services addresses across kernels so that a kexec'd kernel can still
 * use them.
 *
 * This is the main reason why we're doing stable VA mappings for RT
 * services.
 */

#define EFI32_LOADER_SIGNATURE	"EL32"
#define EFI64_LOADER_SIGNATURE	"EL64"

#define ARCH_EFI_IRQ_FLAGS_MASK	X86_EFLAGS_IF

#define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE

/*
 * The EFI services are called through variadic functions in many cases. These
 * functions are implemented in assembler and support only a fixed number of
 * arguments. The macros below allows us to check at build time that we don't
 * try to call them with too many arguments.
 *
 * __efi_nargs() will return the number of arguments if it is 7 or less, and
 * cause a BUILD_BUG otherwise. The limitations of the C preprocessor make it
 * impossible to calculate the exact number of arguments beyond some
 * pre-defined limit. The maximum number of arguments currently supported by
 * any of the thunks is 7, so this is good enough for now and can be extended
 * in the obvious way if we ever need more.
 */

#define __efi_nargs(...) __efi_nargs_(__VA_ARGS__)
#define __efi_nargs_(...) __efi_nargs__(0, ##__VA_ARGS__,	\
	__efi_arg_sentinel(9), __efi_arg_sentinel(8),		\
	__efi_arg_sentinel(7), __efi_arg_sentinel(6),		\
	__efi_arg_sentinel(5), __efi_arg_sentinel(4),		\
	__efi_arg_sentinel(3), __efi_arg_sentinel(2),		\
	__efi_arg_sentinel(1), __efi_arg_sentinel(0))
#define __efi_nargs__(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, ...)	\
	__take_second_arg(n,					\
		({ BUILD_BUG_ON_MSG(1, "__efi_nargs limit exceeded"); 10; }))
#define __efi_arg_sentinel(n) , n

/*
 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
 * represents more than n arguments.
 */

#define __efi_nargs_check(f, n, ...)					\
	__efi_nargs_check_(f, __efi_nargs(__VA_ARGS__), n)
#define __efi_nargs_check_(f, p, n) __efi_nargs_check__(f, p, n)
#define __efi_nargs_check__(f, p, n) ({					\
	BUILD_BUG_ON_MSG(						\
		(p) > (n),						\
		#f " called with too many arguments (" #p ">" #n ")");	\
})

static inline void efi_fpu_begin(void)
{
	/*
	 * The UEFI calling convention (UEFI spec 2.3.2 and 2.3.4) requires
	 * that FCW and MXCSR (64-bit) must be initialized prior to calling
	 * UEFI code.  (Oddly the spec does not require that the FPU stack
	 * be empty.)
	 */
	kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR);
}

static inline void efi_fpu_end(void)
{
	kernel_fpu_end();
}

#ifdef CONFIG_X86_32
#define EFI_X86_KERNEL_ALLOC_LIMIT		(SZ_512M - 1)
#else /* !CONFIG_X86_32 */
#define EFI_X86_KERNEL_ALLOC_LIMIT		EFI_ALLOC_LIMIT

extern asmlinkage u64 __efi_call(void *fp, ...);

extern bool efi_disable_ibt_for_runtime;

#define efi_call(...) ({						\
	__efi_nargs_check(efi_call, 7, __VA_ARGS__);			\
	__efi_call(__VA_ARGS__);					\
})

#undef arch_efi_call_virt
#define arch_efi_call_virt(p, f, args...) ({				\
	u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime);		\
	ret = efi_call((void *)p->f, args);				\
	ibt_restore(ibt);						\
	ret;								\
})

#ifdef CONFIG_KASAN
/*
 * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
 * only in kernel binary.  Since the EFI stub linked into a separate binary it
 * doesn't have __memset().  So we should use standard memset from
 * arch/x86/boot/compressed/string.c.  The same applies to memcpy and memmove.
 */
#undef memcpy
#undef memset
#undef memmove
#endif

#endif /* CONFIG_X86_32 */

extern int __init efi_memblock_x86_reserve_range(void);
extern void __init efi_print_memmap(void);
extern void __init efi_map_region(efi_memory_desc_t *md);
extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
extern void efi_sync_low_kernel_mappings(void);
extern int __init efi_alloc_page_tables(void);
extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
extern void __init efi_runtime_update_mappings(void);
extern void __init efi_dump_pagetable(void);
extern void __init efi_apply_memmap_quirks(void);
extern int __init efi_reuse_config(u64 tables, int nr_tables);
extern void efi_delete_dummy_variable(void);
extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
extern void efi_free_boot_services(void);

void arch_efi_call_virt_setup(void);
void arch_efi_call_virt_teardown(void);

extern u64 efi_setup;

#ifdef CONFIG_EFI
extern u64 __efi64_thunk(u32, ...);

#define efi64_thunk(...) ({						\
	u64 __pad[3]; /* must have space for 3 args on the stack */	\
	__efi_nargs_check(efi64_thunk, 9, __VA_ARGS__);			\
	__efi64_thunk(__VA_ARGS__, __pad);				\
})

static inline bool efi_is_mixed(void)
{
	if (!IS_ENABLED(CONFIG_EFI_MIXED))
		return false;
	return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
}

static inline bool efi_runtime_supported(void)
{
	if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
		return true;

	return IS_ENABLED(CONFIG_EFI_MIXED);
}

extern void parse_efi_setup(u64 phys_addr, u32 data_len);

extern void efi_thunk_runtime_setup(void);
efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
					 unsigned long descriptor_size,
					 u32 descriptor_version,
					 efi_memory_desc_t *virtual_map,
					 unsigned long systab_phys);

/* arch specific definitions used by the stub code */

#ifdef CONFIG_EFI_MIXED

#define EFI_ALLOC_LIMIT		(efi_is_64bit() ? ULONG_MAX : U32_MAX)

#define ARCH_HAS_EFISTUB_WRAPPERS

static inline bool efi_is_64bit(void)
{
	extern const bool efi_is64;

	return efi_is64;
}

static inline bool efi_is_native(void)
{
	return efi_is_64bit();
}

#define efi_table_attr(inst, attr)					\
	(efi_is_native() ? (inst)->attr					\
			 : efi_mixed_table_attr((inst), attr))

#define efi_mixed_table_attr(inst, attr)				\
	(__typeof__(inst->attr))					\
		_Generic(inst->mixed_mode.attr,				\
		u32:		(unsigned long)(inst->mixed_mode.attr),	\
		default:	(inst->mixed_mode.attr))

/*
 * The following macros allow translating arguments if necessary from native to
 * mixed mode. The use case for this is to initialize the upper 32 bits of
 * output parameters, and where the 32-bit method requires a 64-bit argument,
 * which must be split up into two arguments to be thunked properly.
 *
 * As examples, the AllocatePool boot service returns the address of the
 * allocation, but it will not set the high 32 bits of the address. To ensure
 * that the full 64-bit address is initialized, we zero-init the address before
 * calling the thunk.
 *
 * The FreePages boot service takes a 64-bit physical address even in 32-bit
 * mode. For the thunk to work correctly, a native 64-bit call of
 * 	free_pages(addr, size)
 * must be translated to
 * 	efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size)
 * so that the two 32-bit halves of addr get pushed onto the stack separately.
 */

static inline void *efi64_zero_upper(void *p)
{
	((u32 *)p)[1] = 0;
	return p;
}

static inline u32 efi64_convert_status(efi_status_t status)
{
	return (u32)(status | (u64)status >> 32);
}

#define __efi64_split(val)		(val) & U32_MAX, (u64)(val) >> 32

#define __efi64_argmap_free_pages(addr, size)				\
	((addr), 0, (size))

#define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver)	\
	((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver))

#define __efi64_argmap_allocate_pool(type, size, buffer)		\
	((type), (size), efi64_zero_upper(buffer))

#define __efi64_argmap_create_event(type, tpl, f, c, event)		\
	((type), (tpl), (f), (c), efi64_zero_upper(event))

#define __efi64_argmap_set_timer(event, type, time)			\
	((event), (type), lower_32_bits(time), upper_32_bits(time))

#define __efi64_argmap_wait_for_event(num, event, index)		\
	((num), (event), efi64_zero_upper(index))

#define __efi64_argmap_handle_protocol(handle, protocol, interface)	\
	((handle), (protocol), efi64_zero_upper(interface))

#define __efi64_argmap_locate_protocol(protocol, reg, interface)	\
	((protocol), (reg), efi64_zero_upper(interface))

#define __efi64_argmap_locate_device_path(protocol, path, handle)	\
	((protocol), (path), efi64_zero_upper(handle))

#define __efi64_argmap_exit(handle, status, size, data)			\
	((handle), efi64_convert_status(status), (size), (data))

/* PCI I/O */
#define __efi64_argmap_get_location(protocol, seg, bus, dev, func)	\
	((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus),	\
	 efi64_zero_upper(dev), efi64_zero_upper(func))

/* LoadFile */
#define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf)	\
	((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))

/* Graphics Output Protocol */
#define __efi64_argmap_query_mode(gop, mode, size, info)		\
	((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info))

/* TCG2 protocol */
#define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev)	\
	((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)

/* DXE services */
#define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
	(__efi64_split(phys), (desc))

#define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
	(__efi64_split(phys), __efi64_split(size), __efi64_split(flags))

/* file protocol */
#define __efi64_argmap_open(prot, newh, fname, mode, attr) \
	((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
	 __efi64_split(attr))

#define __efi64_argmap_set_position(pos) (__efi64_split(pos))

/* file system protocol */
#define __efi64_argmap_open_volume(prot, file) \
	((prot), efi64_zero_upper(file))

/* Memory Attribute Protocol */
#define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
	((protocol), __efi64_split(phys), __efi64_split(size), (flags))

#define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
	((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))

#define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
	((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))

/*
 * The macros below handle the plumbing for the argument mapping. To add a
 * mapping for a specific EFI method, simply define a macro
 * __efi64_argmap_<method name>, following the examples above.
 */

#define __efi64_thunk_map(inst, func, ...)				\
	efi64_thunk(inst->mixed_mode.func,				\
		__efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__),	\
			       (__VA_ARGS__)))

#define __efi64_argmap(mapped, args)					\
	__PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args)
#define __efi64_argmap__0(mapped, args) __efi_eval mapped
#define __efi64_argmap__1(mapped, args) __efi_eval args

#define __efi_eat(...)
#define __efi_eval(...) __VA_ARGS__

static inline efi_status_t __efi64_widen_efi_status(u64 status)
{
	/* use rotate to move the value of bit #31 into position #63 */
	return ror64(rol32(status, 1), 1);
}

/* The macro below handles dispatching via the thunk if needed */

#define efi_fn_call(inst, func, ...)					\
	(efi_is_native() ? (inst)->func(__VA_ARGS__)			\
			 : efi_mixed_call((inst), func, ##__VA_ARGS__))

#define efi_mixed_call(inst, func, ...)					\
	_Generic(inst->func(__VA_ARGS__),				\
	efi_status_t:							\
		__efi64_widen_efi_status(				\
			__efi64_thunk_map(inst, func, ##__VA_ARGS__)),	\
	u64: ({ BUILD_BUG(); ULONG_MAX; }),				\
	default:							\
		(__typeof__(inst->func(__VA_ARGS__)))			\
			__efi64_thunk_map(inst, func, ##__VA_ARGS__))

#else /* CONFIG_EFI_MIXED */

static inline bool efi_is_64bit(void)
{
	return IS_ENABLED(CONFIG_X86_64);
}

#endif /* CONFIG_EFI_MIXED */

extern bool efi_reboot_required(void);
extern bool efi_is_table_address(unsigned long phys_addr);

extern void efi_reserve_boot_services(void);
#else
static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
static inline bool efi_reboot_required(void)
{
	return false;
}
static inline  bool efi_is_table_address(unsigned long phys_addr)
{
	return false;
}
static inline void efi_reserve_boot_services(void)
{
}
#endif /* CONFIG_EFI */

#ifdef CONFIG_EFI_FAKE_MEMMAP
extern void __init efi_fake_memmap_early(void);
extern void __init efi_fake_memmap(void);
#else
static inline void efi_fake_memmap_early(void)
{
}

static inline void efi_fake_memmap(void)
{
}
#endif

extern int __init efi_memmap_alloc(unsigned int num_entries,
				   struct efi_memory_map_data *data);
extern void __efi_memmap_free(u64 phys, unsigned long size,
			      unsigned long flags);

extern int __init efi_memmap_install(struct efi_memory_map_data *data);
extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
					 struct range *range);
extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
				     void *buf, struct efi_mem_range *mem);

extern enum efi_secureboot_mode __x86_ima_efi_boot_mode(void);

#define arch_ima_efi_boot_mode	__x86_ima_efi_boot_mode()

#ifdef CONFIG_EFI_RUNTIME_MAP
int efi_get_runtime_map_size(void);
int efi_get_runtime_map_desc_size(void);
int efi_runtime_map_copy(void *buf, size_t bufsz);
#else
static inline int efi_get_runtime_map_size(void)
{
	return 0;
}

static inline int efi_get_runtime_map_desc_size(void)
{
	return 0;
}

static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
{
	return 0;
}

#endif

#endif /* _ASM_X86_EFI_H */