1 files changed, 314 insertions, 139 deletions

diff --git a/arch/x86/include/asm/efi.h b/arch/x86/include/asm/efi.h
index 107283b1eb1e..f227a70ac91f 100644
--- a/arch/x86/include/asm/efi.h
+++ b/arch/x86/include/asm/efi.h
@@ -3,11 +3,17 @@
 #define _ASM_X86_EFI_H
 
 #include <asm/fpu/api.h>
-#include <asm/pgtable.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,
@@ -18,92 +24,93 @@
  *
  * This is the main reason why we're doing stable VA mappings for RT
  * services.
- *
- * This flag is used in conjunction with a chicken bit called
- * "efi=old_map" which can be used as a fallback to the old runtime
- * services mapping method in case there's some b0rkage with a
- * particular EFI implementation (haha, it is hard to hold up the
- * sarcasm here...).
  */
-#define EFI_OLD_MEMMAP		EFI_ARCH_1
 
 #define EFI32_LOADER_SIGNATURE	"EL32"
 #define EFI64_LOADER_SIGNATURE	"EL64"
 
-#define MAX_CMDLINE_ADDRESS	UINT_MAX
-
 #define ARCH_EFI_IRQ_FLAGS_MASK	X86_EFLAGS_IF
 
-#ifdef CONFIG_X86_32
-
-extern asmlinkage unsigned long efi_call_phys(void *, ...);
-
-#define arch_efi_call_virt_setup()					\
-({									\
-	kernel_fpu_begin();						\
-	firmware_restrict_branch_speculation_start();			\
-})
+#define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE
 
-#define arch_efi_call_virt_teardown()					\
-({									\
-	firmware_restrict_branch_speculation_end();			\
-	kernel_fpu_end();						\
-})
+/*
+ * 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
 
 /*
- * Wrap all the virtual calls in a way that forces the parameters on the stack.
+ * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
+ * represents more than n arguments.
  */
-#define arch_efi_call_virt(p, f, args...)				\
-({									\
-	((efi_##f##_t __attribute__((regparm(0)))*) p->f)(args);	\
+
+#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 ")");	\
 })
 
-#define efi_ioremap(addr, size, type, attr)	ioremap_cache(addr, size)
+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);
+}
 
-#else /* !CONFIG_X86_32 */
+static inline void efi_fpu_end(void)
+{
+	kernel_fpu_end();
+}
 
-#define EFI_LOADER_SIGNATURE	"EL64"
+#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 asmlinkage u64 __efi_call(void *fp, ...);
 
-#define efi_call_phys(f, args...)		efi_call((f), args)
+extern bool efi_disable_ibt_for_runtime;
 
-/*
- * struct efi_scratch - Scratch space used while switching to/from efi_mm
- * @phys_stack: stack used during EFI Mixed Mode
- * @prev_mm:    store/restore stolen mm_struct while switching to/from efi_mm
- */
-struct efi_scratch {
-	u64			phys_stack;
-	struct mm_struct	*prev_mm;
-} __packed;
-
-#define arch_efi_call_virt_setup()					\
-({									\
-	efi_sync_low_kernel_mappings();					\
-	kernel_fpu_begin();						\
-	firmware_restrict_branch_speculation_start();			\
-									\
-	if (!efi_enabled(EFI_OLD_MEMMAP))				\
-		efi_switch_mm(&efi_mm);					\
+#define efi_call(...) ({						\
+	__efi_nargs_check(efi_call, 7, __VA_ARGS__);			\
+	__efi_call(__VA_ARGS__);					\
 })
 
-#define arch_efi_call_virt(p, f, args...)				\
-	efi_call((void *)p->f, args)					\
-
-#define arch_efi_call_virt_teardown()					\
-({									\
-	if (!efi_enabled(EFI_OLD_MEMMAP))				\
-		efi_switch_mm(efi_scratch.prev_mm);			\
-									\
-	firmware_restrict_branch_speculation_end();			\
-	kernel_fpu_end();						\
+#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;								\
 })
 
-extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
-					u32 type, u64 attribute);
-
 #ifdef CONFIG_KASAN
 /*
  * CONFIG_KASAN may redefine memset to __memset.  __memset function is present
@@ -118,138 +125,306 @@ extern void __iomem *__init efi_ioremap(unsigned long addr, unsigned long size,
 
 #endif /* CONFIG_X86_32 */
 
-extern struct efi_scratch efi_scratch;
-extern void __init efi_set_executable(efi_memory_desc_t *md, bool executable);
 extern int __init efi_memblock_x86_reserve_range(void);
-extern pgd_t * __init efi_call_phys_prolog(void);
-extern void __init efi_call_phys_epilog(pgd_t *save_pgd);
 extern void __init efi_print_memmap(void);
-extern void __init efi_memory_uc(u64 addr, unsigned long size);
 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 old_map_region(efi_memory_desc_t *md);
-extern void __init runtime_code_page_mkexec(void);
 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_switch_mm(struct mm_struct *mm);
-extern void efi_recover_from_page_fault(unsigned long phys_addr);
+extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
 extern void efi_free_boot_services(void);
-extern void efi_reserve_boot_services(void);
 
-struct efi_setup_data {
-	u64 fw_vendor;
-	u64 runtime;
-	u64 tables;
-	u64 smbios;
-	u64 reserved[8];
-};
+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, ...);
 
-static inline bool efi_is_native(void)
+#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)
 {
-	return IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT);
+	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 (efi_is_native())
+	if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
 		return true;
 
-	if (IS_ENABLED(CONFIG_EFI_MIXED) && !efi_enabled(EFI_OLD_MEMMAP))
-		return true;
-
-	return false;
+	return IS_ENABLED(CONFIG_EFI_MIXED);
 }
 
-extern struct console early_efi_console;
 extern void parse_efi_setup(u64 phys_addr, u32 data_len);
 
-extern void efifb_setup_from_dmi(struct screen_info *si, const char *opt);
+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
-extern void efi_thunk_runtime_setup(void);
-extern efi_status_t efi_thunk_set_virtual_address_map(
-	void *phys_set_virtual_address_map,
-	unsigned long memory_map_size,
-	unsigned long descriptor_size,
-	u32 descriptor_version,
-	efi_memory_desc_t *virtual_map);
-#else
-static inline void efi_thunk_runtime_setup(void) {}
-static inline efi_status_t efi_thunk_set_virtual_address_map(
-	void *phys_set_virtual_address_map,
-	unsigned long memory_map_size,
-	unsigned long descriptor_size,
-	u32 descriptor_version,
-	efi_memory_desc_t *virtual_map)
+
+#define EFI_ALLOC_LIMIT		(efi_is_64bit() ? ULONG_MAX : U32_MAX)
+
+#define ARCH_HAS_EFISTUB_WRAPPERS
+
+static inline bool efi_is_64bit(void)
 {
-	return EFI_SUCCESS;
+	extern const bool efi_is64;
+
+	return efi_is64;
 }
-#endif /* CONFIG_EFI_MIXED */
 
+static inline bool efi_is_native(void)
+{
+	return efi_is_64bit();
+}
 
-/* arch specific definitions used by the stub code */
+#define efi_table_attr(inst, attr)					\
+	(efi_is_native() ? (inst)->attr					\
+			 : efi_mixed_table_attr((inst), attr))
 
-struct efi_config {
-	u64 image_handle;
-	u64 table;
-	u64 runtime_services;
-	u64 boot_services;
-	u64 text_output;
-	efi_status_t (*call)(unsigned long, ...);
-	bool is64;
-} __packed;
+#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))
 
-__pure const struct efi_config *__efi_early(void);
+/*
+ * 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 bool efi_is_64bit(void)
+static inline void *efi64_zero_upper(void *p)
 {
-	if (!IS_ENABLED(CONFIG_X86_64))
-		return false;
+	if (p)
+		((u32 *)p)[1] = 0;
+	return p;
+}
 
-	if (!IS_ENABLED(CONFIG_EFI_MIXED))
-		return true;
+static inline u32 efi64_convert_status(efi_status_t status)
+{
+	return (u32)(status | (u64)status >> 32);
+}
 
-	return __efi_early()->is64;
+#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_locate_handle_buffer(type, proto, key, num, buf)	\
+	((type), (proto), (key), efi64_zero_upper(num), efi64_zero_upper(buf))
+
+#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))
+
+/* EFI SMBIOS protocol */
+#define __efi64_argmap_get_next(protocol, smbioshandle, type, record, phandle) \
+	((protocol), (smbioshandle), (type), efi64_zero_upper(record), \
+	 efi64_zero_upper(phandle))
+/*
+ * 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);
 }
 
-#define efi_table_attr(table, attr, instance)				\
-	(efi_is_64bit() ?						\
-		((table##_64_t *)(unsigned long)instance)->attr :	\
-		((table##_32_t *)(unsigned long)instance)->attr)
+/* The macro below handles dispatching via the thunk if needed */
 
-#define efi_call_proto(protocol, f, instance, ...)			\
-	__efi_early()->call(efi_table_attr(protocol, f, instance),	\
-		instance, ##__VA_ARGS__)
+#define efi_fn_call(inst, func, ...)					\
+	(efi_is_native() ? (inst)->func(__VA_ARGS__)			\
+			 : efi_mixed_call((inst), func, ##__VA_ARGS__))
 
-#define efi_call_early(f, ...)						\
-	__efi_early()->call(efi_table_attr(efi_boot_services, f,	\
-		__efi_early()->boot_services), __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__))
 
-#define __efi_call_early(f, ...)					\
-	__efi_early()->call((unsigned long)f, __VA_ARGS__);
+#else /* CONFIG_EFI_MIXED */
+
+static inline bool efi_is_64bit(void)
+{
+	return IS_ENABLED(CONFIG_X86_64);
+}
 
-#define efi_call_runtime(f, ...)					\
-	__efi_early()->call(efi_table_attr(efi_runtime_services, f,	\
-		__efi_early()->runtime_services), __VA_ARGS__)
+#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 */
 
+extern int __init efi_memmap_alloc(unsigned int num_entries,
+				   struct efi_memory_map_data *data);
+
+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 */