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-rw-r--r--arch/x86/include/asm/linkage.h151
1 files changed, 151 insertions, 0 deletions
diff --git a/arch/x86/include/asm/linkage.h b/arch/x86/include/asm/linkage.h
new file mode 100644
index 0000000000..571fe4d2d2
--- /dev/null
+++ b/arch/x86/include/asm/linkage.h
@@ -0,0 +1,151 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_LINKAGE_H
+#define _ASM_X86_LINKAGE_H
+
+#include <linux/stringify.h>
+#include <asm/ibt.h>
+
+#undef notrace
+#define notrace __attribute__((no_instrument_function))
+
+#ifdef CONFIG_64BIT
+/*
+ * The generic version tends to create spurious ENDBR instructions under
+ * certain conditions.
+ */
+#define _THIS_IP_ ({ unsigned long __here; asm ("lea 0(%%rip), %0" : "=r" (__here)); __here; })
+#endif
+
+#ifdef CONFIG_X86_32
+#define asmlinkage CPP_ASMLINKAGE __attribute__((regparm(0)))
+#endif /* CONFIG_X86_32 */
+
+#define __ALIGN .balign CONFIG_FUNCTION_ALIGNMENT, 0x90;
+#define __ALIGN_STR __stringify(__ALIGN)
+
+#if defined(CONFIG_CALL_PADDING) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
+#define FUNCTION_PADDING .skip CONFIG_FUNCTION_ALIGNMENT, 0x90;
+#else
+#define FUNCTION_PADDING
+#endif
+
+#if (CONFIG_FUNCTION_ALIGNMENT > 8) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
+# define __FUNC_ALIGN __ALIGN; FUNCTION_PADDING
+#else
+# define __FUNC_ALIGN __ALIGN
+#endif
+
+#define ASM_FUNC_ALIGN __stringify(__FUNC_ALIGN)
+#define SYM_F_ALIGN __FUNC_ALIGN
+
+#ifdef __ASSEMBLY__
+
+#if defined(CONFIG_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
+#define RET jmp __x86_return_thunk
+#else /* CONFIG_RETPOLINE */
+#ifdef CONFIG_SLS
+#define RET ret; int3
+#else
+#define RET ret
+#endif
+#endif /* CONFIG_RETPOLINE */
+
+#else /* __ASSEMBLY__ */
+
+#if defined(CONFIG_RETHUNK) && !defined(__DISABLE_EXPORTS) && !defined(BUILD_VDSO)
+#define ASM_RET "jmp __x86_return_thunk\n\t"
+#else /* CONFIG_RETPOLINE */
+#ifdef CONFIG_SLS
+#define ASM_RET "ret; int3\n\t"
+#else
+#define ASM_RET "ret\n\t"
+#endif
+#endif /* CONFIG_RETPOLINE */
+
+#endif /* __ASSEMBLY__ */
+
+/*
+ * Depending on -fpatchable-function-entry=N,N usage (CONFIG_CALL_PADDING) the
+ * CFI symbol layout changes.
+ *
+ * Without CALL_THUNKS:
+ *
+ * .align FUNCTION_ALIGNMENT
+ * __cfi_##name:
+ * .skip FUNCTION_PADDING, 0x90
+ * .byte 0xb8
+ * .long __kcfi_typeid_##name
+ * name:
+ *
+ * With CALL_THUNKS:
+ *
+ * .align FUNCTION_ALIGNMENT
+ * __cfi_##name:
+ * .byte 0xb8
+ * .long __kcfi_typeid_##name
+ * .skip FUNCTION_PADDING, 0x90
+ * name:
+ *
+ * In both cases the whole thing is FUNCTION_ALIGNMENT aligned and sized.
+ */
+
+#ifdef CONFIG_CALL_PADDING
+#define CFI_PRE_PADDING
+#define CFI_POST_PADDING .skip CONFIG_FUNCTION_PADDING_BYTES, 0x90;
+#else
+#define CFI_PRE_PADDING .skip CONFIG_FUNCTION_PADDING_BYTES, 0x90;
+#define CFI_POST_PADDING
+#endif
+
+#define __CFI_TYPE(name) \
+ SYM_START(__cfi_##name, SYM_L_LOCAL, SYM_A_NONE) \
+ CFI_PRE_PADDING \
+ .byte 0xb8 ASM_NL \
+ .long __kcfi_typeid_##name ASM_NL \
+ CFI_POST_PADDING \
+ SYM_FUNC_END(__cfi_##name)
+
+/* UML needs to be able to override memcpy() and friends for KASAN. */
+#ifdef CONFIG_UML
+# define SYM_FUNC_ALIAS_MEMFUNC SYM_FUNC_ALIAS_WEAK
+#else
+# define SYM_FUNC_ALIAS_MEMFUNC SYM_FUNC_ALIAS
+#endif
+
+/* SYM_TYPED_FUNC_START -- use for indirectly called globals, w/ CFI type */
+#define SYM_TYPED_FUNC_START(name) \
+ SYM_TYPED_START(name, SYM_L_GLOBAL, SYM_F_ALIGN) \
+ ENDBR
+
+/* SYM_FUNC_START -- use for global functions */
+#define SYM_FUNC_START(name) \
+ SYM_START(name, SYM_L_GLOBAL, SYM_F_ALIGN) \
+ ENDBR
+
+/* SYM_FUNC_START_NOALIGN -- use for global functions, w/o alignment */
+#define SYM_FUNC_START_NOALIGN(name) \
+ SYM_START(name, SYM_L_GLOBAL, SYM_A_NONE) \
+ ENDBR
+
+/* SYM_FUNC_START_LOCAL -- use for local functions */
+#define SYM_FUNC_START_LOCAL(name) \
+ SYM_START(name, SYM_L_LOCAL, SYM_F_ALIGN) \
+ ENDBR
+
+/* SYM_FUNC_START_LOCAL_NOALIGN -- use for local functions, w/o alignment */
+#define SYM_FUNC_START_LOCAL_NOALIGN(name) \
+ SYM_START(name, SYM_L_LOCAL, SYM_A_NONE) \
+ ENDBR
+
+/* SYM_FUNC_START_WEAK -- use for weak functions */
+#define SYM_FUNC_START_WEAK(name) \
+ SYM_START(name, SYM_L_WEAK, SYM_F_ALIGN) \
+ ENDBR
+
+/* SYM_FUNC_START_WEAK_NOALIGN -- use for weak functions, w/o alignment */
+#define SYM_FUNC_START_WEAK_NOALIGN(name) \
+ SYM_START(name, SYM_L_WEAK, SYM_A_NONE) \
+ ENDBR
+
+#endif /* _ASM_X86_LINKAGE_H */
+