| 1 | /* SPDX-License-Identifier: GPL-2.0 */ | 
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| 2 | #ifndef _ASM_X86_JUMP_LABEL_H | 
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| 3 | #define _ASM_X86_JUMP_LABEL_H | 
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| 4 |  | 
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| 5 | #define HAVE_JUMP_LABEL_BATCH | 
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| 6 |  | 
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| 7 | #include <asm/asm.h> | 
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| 8 | #include <asm/nops.h> | 
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| 9 |  | 
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| 10 | #ifndef __ASSEMBLER__ | 
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| 11 |  | 
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| 12 | #include <linux/stringify.h> | 
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| 13 | #include <linux/types.h> | 
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| 14 |  | 
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| 15 | #define JUMP_TABLE_ENTRY(key, label)			\ | 
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| 16 | ".pushsection __jump_table,  \"aw\" \n\t"	\ | 
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| 17 | _ASM_ALIGN "\n\t"				\ | 
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| 18 | ".long 1b - . \n\t"				\ | 
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| 19 | ".long " label " - . \n\t"			\ | 
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| 20 | _ASM_PTR " " key " - . \n\t"			\ | 
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| 21 | ".popsection \n\t" | 
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| 22 |  | 
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| 23 | /* This macro is also expanded on the Rust side. */ | 
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| 24 | #ifdef CONFIG_HAVE_JUMP_LABEL_HACK | 
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| 25 | #define ARCH_STATIC_BRANCH_ASM(key, label)		\ | 
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| 26 | "1: jmp " label " # objtool NOPs this \n\t"	\ | 
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| 27 | JUMP_TABLE_ENTRY(key " + 2", label) | 
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| 28 | #else /* !CONFIG_HAVE_JUMP_LABEL_HACK */ | 
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| 29 | #define ARCH_STATIC_BRANCH_ASM(key, label)		\ | 
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| 30 | "1: .byte " __stringify(BYTES_NOP5) "\n\t"	\ | 
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| 31 | JUMP_TABLE_ENTRY(key, label) | 
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| 32 | #endif /* CONFIG_HAVE_JUMP_LABEL_HACK */ | 
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| 33 |  | 
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| 34 | static __always_inline bool arch_static_branch(struct static_key * const key, const bool branch) | 
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| 35 | { | 
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| 36 | asm goto(ARCH_STATIC_BRANCH_ASM( "%c0 + %c1", "%l[l_yes]") | 
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| 37 | : : "i"(key), "i"(branch) : : l_yes); | 
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| 38 |  | 
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| 39 | return false; | 
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| 40 | l_yes: | 
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| 41 | return true; | 
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| 42 | } | 
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| 43 |  | 
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| 44 | static __always_inline bool arch_static_branch_jump(struct static_key * const key, const bool branch) | 
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| 45 | { | 
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| 46 | asm goto( "1:" | 
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| 47 | "jmp %l[l_yes]\n\t" | 
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| 48 | JUMP_TABLE_ENTRY( "%c0 + %c1", "%l[l_yes]") | 
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| 49 | : : "i"(key), "i"(branch) : : l_yes); | 
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| 50 |  | 
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| 51 | return false; | 
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| 52 | l_yes: | 
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| 53 | return true; | 
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| 54 | } | 
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| 55 |  | 
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| 56 | extern int arch_jump_entry_size(struct jump_entry *entry); | 
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| 57 |  | 
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| 58 | #endif	/* __ASSEMBLER__ */ | 
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| 59 |  | 
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| 60 | #endif | 
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| 61 |  | 
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