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-rw-r--r--arch/x86/include/asm/efi.h412
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diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
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+++ b/arch/x86/include/asm/efi.h
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+/* 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
+
+/*
+ * 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 arch_efi_call_virt_setup() \
+({ \
+ efi_fpu_begin(); \
+ firmware_restrict_branch_speculation_start(); \
+})
+
+#define arch_efi_call_virt_teardown() \
+({ \
+ firmware_restrict_branch_speculation_end(); \
+ efi_fpu_end(); \
+})
+
+#else /* !CONFIG_X86_32 */
+
+#define EFI_LOADER_SIGNATURE "EL64"
+
+extern asmlinkage u64 __efi_call(void *fp, ...);
+
+#define efi_call(...) ({ \
+ __efi_nargs_check(efi_call, 7, __VA_ARGS__); \
+ __efi_call(__VA_ARGS__); \
+})
+
+#define arch_efi_call_virt_setup() \
+({ \
+ efi_sync_low_kernel_mappings(); \
+ efi_fpu_begin(); \
+ firmware_restrict_branch_speculation_start(); \
+ efi_enter_mm(); \
+})
+
+#undef arch_efi_call_virt
+#define arch_efi_call_virt(p, f, args...) ({ \
+ u64 ret, ibt = ibt_save(); \
+ ret = efi_call((void *)p->f, args); \
+ ibt_restore(ibt); \
+ ret; \
+})
+
+#define arch_efi_call_virt_teardown() \
+({ \
+ efi_leave_mm(); \
+ firmware_restrict_branch_speculation_end(); \
+ efi_fpu_end(); \
+})
+
+#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 efi_enter_mm(void);
+void efi_leave_mm(void);
+
+/* kexec external ABI */
+struct efi_setup_data {
+ u64 fw_vendor;
+ u64 __unused;
+ u64 tables;
+ u64 smbios;
+ u64 reserved[8];
+};
+
+extern u64 efi_setup;
+
+#ifdef CONFIG_EFI
+extern efi_status_t __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 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_mixed_mode_cast(attr) \
+ __builtin_choose_expr( \
+ __builtin_types_compatible_p(u32, __typeof__(attr)), \
+ (unsigned long)(attr), (attr))
+
+#define efi_table_attr(inst, attr) \
+ (efi_is_native() \
+ ? inst->attr \
+ : (__typeof__(inst->attr)) \
+ efi_mixed_mode_cast(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))
+
+/*
+ * 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__
+
+/* The three macros below handle dispatching via the thunk if needed */
+
+#define efi_call_proto(inst, func, ...) \
+ (efi_is_native() \
+ ? inst->func(inst, ##__VA_ARGS__) \
+ : __efi64_thunk_map(inst, func, inst, ##__VA_ARGS__))
+
+#define efi_bs_call(func, ...) \
+ (efi_is_native() \
+ ? efi_system_table->boottime->func(__VA_ARGS__) \
+ : __efi64_thunk_map(efi_table_attr(efi_system_table, \
+ boottime), \
+ func, __VA_ARGS__))
+
+#define efi_rt_call(func, ...) \
+ (efi_is_native() \
+ ? efi_system_table->runtime->func(__VA_ARGS__) \
+ : __efi64_thunk_map(efi_table_attr(efi_system_table, \
+ runtime), \
+ func, __VA_ARGS__))
+
+#define efi_dxe_call(func, ...) \
+ (efi_is_native() \
+ ? efi_dxe_table->func(__VA_ARGS__) \
+ : __efi64_thunk_map(efi_dxe_table, 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);
+#else
+static inline void efi_fake_memmap_early(void)
+{
+}
+#endif
+
+#define arch_ima_efi_boot_mode \
+ ({ extern struct boot_params boot_params; boot_params.secure_boot; })
+
+#endif /* _ASM_X86_EFI_H */
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