43 lines
749 B
C
43 lines
749 B
C
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#ifndef _ASM_X86_JUMP_LABEL_H
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#define _ASM_X86_JUMP_LABEL_H
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#ifdef __KERNEL__
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#include <linux/types.h>
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#include <asm/nops.h>
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#include <asm/asm.h>
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#define JUMP_LABEL_NOP_SIZE 5
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#define STATIC_KEY_INITIAL_NOP ".byte 0xe9 \n\t .long 0\n\t"
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static __always_inline bool arch_static_branch(struct static_key *key)
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{
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asm goto("1:"
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STATIC_KEY_INITIAL_NOP
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".pushsection __jump_table, \"aw\" \n\t"
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_ASM_ALIGN "\n\t"
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_ASM_PTR "1b, %l[l_yes], %c0 \n\t"
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".popsection \n\t"
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: : "i" (key) : : l_yes);
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return false;
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l_yes:
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return true;
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}
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#endif /* __KERNEL__ */
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#ifdef CONFIG_X86_64
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typedef u64 jump_label_t;
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#else
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typedef u32 jump_label_t;
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#endif
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struct jump_entry {
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jump_label_t code;
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jump_label_t target;
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jump_label_t key;
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};
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#endif
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