1 /* SPDX-License-Identifier: GPL-2.0 */
5 #include <asm/fpu/api.h>
6 #include <asm/processor-flags.h>
8 #include <asm/nospec-branch.h>
9 #include <asm/mmu_context.h>
11 #include <linux/build_bug.h>
12 #include <linux/kernel.h>
13 #include <linux/pgtable.h>
15 extern unsigned long efi_fw_vendor, efi_config_table;
16 extern unsigned long efi_mixed_mode_stack_pa;
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
25 * This is the main reason why we're doing stable VA mappings for RT
29 #define EFI32_LOADER_SIGNATURE "EL32"
30 #define EFI64_LOADER_SIGNATURE "EL64"
32 #define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
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.
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.
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
61 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
62 * represents more than n arguments.
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) ({ \
71 #f " called with too many arguments (" #p ">" #n ")"); \
74 static inline void efi_fpu_begin(void)
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
82 kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR);
85 static inline void efi_fpu_end(void)
91 #define arch_efi_call_virt_setup() \
94 firmware_restrict_branch_speculation_start(); \
97 #define arch_efi_call_virt_teardown() \
99 firmware_restrict_branch_speculation_end(); \
103 #else /* !CONFIG_X86_32 */
105 #define EFI_LOADER_SIGNATURE "EL64"
107 extern asmlinkage u64 __efi_call(void *fp, ...);
109 extern bool efi_disable_ibt_for_runtime;
111 #define efi_call(...) ({ \
112 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \
113 __efi_call(__VA_ARGS__); \
116 #define arch_efi_call_virt_setup() \
118 efi_sync_low_kernel_mappings(); \
120 firmware_restrict_branch_speculation_start(); \
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); \
132 #define arch_efi_call_virt_teardown() \
135 firmware_restrict_branch_speculation_end(); \
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.
151 #endif /* CONFIG_X86_32 */
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);
168 void efi_enter_mm(void);
169 void efi_leave_mm(void);
171 /* kexec external ABI */
172 struct efi_setup_data {
180 extern u64 efi_setup;
183 extern u64 __efi64_thunk(u32, ...);
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); \
191 static inline bool efi_is_mixed(void)
193 if (!IS_ENABLED(CONFIG_EFI_MIXED))
195 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
198 static inline bool efi_runtime_supported(void)
200 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
203 return IS_ENABLED(CONFIG_EFI_MIXED);
206 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
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);
215 /* arch specific definitions used by the stub code */
217 #ifdef CONFIG_EFI_MIXED
219 #define ARCH_HAS_EFISTUB_WRAPPERS
221 static inline bool efi_is_64bit(void)
223 extern const bool efi_is64;
228 static inline bool efi_is_native(void)
230 return efi_is_64bit();
233 #define efi_table_attr(inst, attr) \
234 (efi_is_native() ? (inst)->attr \
235 : efi_mixed_table_attr((inst), attr))
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))
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.
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
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.
262 static inline void *efi64_zero_upper(void *p)
268 static inline u32 efi64_convert_status(efi_status_t status)
270 return (u32)(status | (u64)status >> 32);
273 #define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32
275 #define __efi64_argmap_free_pages(addr, size) \
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))
281 #define __efi64_argmap_allocate_pool(type, size, buffer) \
282 ((type), (size), efi64_zero_upper(buffer))
284 #define __efi64_argmap_create_event(type, tpl, f, c, event) \
285 ((type), (tpl), (f), (c), efi64_zero_upper(event))
287 #define __efi64_argmap_set_timer(event, type, time) \
288 ((event), (type), lower_32_bits(time), upper_32_bits(time))
290 #define __efi64_argmap_wait_for_event(num, event, index) \
291 ((num), (event), efi64_zero_upper(index))
293 #define __efi64_argmap_handle_protocol(handle, protocol, interface) \
294 ((handle), (protocol), efi64_zero_upper(interface))
296 #define __efi64_argmap_locate_protocol(protocol, reg, interface) \
297 ((protocol), (reg), efi64_zero_upper(interface))
299 #define __efi64_argmap_locate_device_path(protocol, path, handle) \
300 ((protocol), (path), efi64_zero_upper(handle))
302 #define __efi64_argmap_exit(handle, status, size, data) \
303 ((handle), efi64_convert_status(status), (size), (data))
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))
311 #define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \
312 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))
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))
319 #define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \
320 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)
323 #define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
324 (__efi64_split(phys), (desc))
326 #define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
327 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
330 #define __efi64_argmap_open(prot, newh, fname, mode, attr) \
331 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
334 #define __efi64_argmap_set_position(pos) (__efi64_split(pos))
336 /* file system protocol */
337 #define __efi64_argmap_open_volume(prot, file) \
338 ((prot), efi64_zero_upper(file))
340 /* Memory Attribute Protocol */
341 #define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
342 ((protocol), __efi64_split(phys), __efi64_split(size), (flags))
344 #define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
345 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
347 #define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
348 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
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.
356 #define __efi64_thunk_map(inst, func, ...) \
357 efi64_thunk(inst->mixed_mode.func, \
358 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \
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
366 #define __efi_eat(...)
367 #define __efi_eval(...) __VA_ARGS__
369 static inline efi_status_t __efi64_widen_efi_status(u64 status)
371 /* use rotate to move the value of bit #31 into position #63 */
372 return ror64(rol32(status, 1), 1);
375 /* The macro below handles dispatching via the thunk if needed */
377 #define efi_fn_call(inst, func, ...) \
378 (efi_is_native() ? (inst)->func(__VA_ARGS__) \
379 : efi_mixed_call((inst), func, ##__VA_ARGS__))
381 #define efi_mixed_call(inst, func, ...) \
382 _Generic(inst->func(__VA_ARGS__), \
384 __efi64_widen_efi_status( \
385 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \
386 u64: ({ BUILD_BUG(); ULONG_MAX; }), \
388 (__typeof__(inst->func(__VA_ARGS__))) \
389 __efi64_thunk_map(inst, func, ##__VA_ARGS__))
391 #else /* CONFIG_EFI_MIXED */
393 static inline bool efi_is_64bit(void)
395 return IS_ENABLED(CONFIG_X86_64);
398 #endif /* CONFIG_EFI_MIXED */
400 extern bool efi_reboot_required(void);
401 extern bool efi_is_table_address(unsigned long phys_addr);
403 extern void efi_reserve_boot_services(void);
405 static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
406 static inline bool efi_reboot_required(void)
410 static inline bool efi_is_table_address(unsigned long phys_addr)
414 static inline void efi_reserve_boot_services(void)
417 #endif /* CONFIG_EFI */
419 #ifdef CONFIG_EFI_FAKE_MEMMAP
420 extern void __init efi_fake_memmap_early(void);
421 extern void __init efi_fake_memmap(void);
423 static inline void efi_fake_memmap_early(void)
427 static inline void efi_fake_memmap(void)
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
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);
444 #define arch_ima_efi_boot_mode \
445 ({ extern struct boot_params boot_params; boot_params.secure_boot; })
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);
452 static inline int efi_get_runtime_map_size(void)
457 static inline int efi_get_runtime_map_desc_size(void)
462 static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
469 #endif /* _ASM_X86_EFI_H */