63 lines
1.4 KiB
C
63 lines
1.4 KiB
C
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/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* Copyright (C) 2020 Emil Renner Berthing
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*
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* Based on arch/arm64/include/asm/jump_label.h
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*/
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#ifndef __ASM_JUMP_LABEL_H
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#define __ASM_JUMP_LABEL_H
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#ifndef __ASSEMBLY__
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#include <linux/types.h>
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#include <asm/asm.h>
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#define JUMP_LABEL_NOP_SIZE 4
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static __always_inline bool arch_static_branch(struct static_key * const key,
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const bool branch)
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{
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asm_volatile_goto(
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" .align 2 \n\t"
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" .option push \n\t"
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" .option norelax \n\t"
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" .option norvc \n\t"
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"1: nop \n\t"
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" .option pop \n\t"
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" .pushsection __jump_table, \"aw\" \n\t"
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" .align " RISCV_LGPTR " \n\t"
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" .long 1b - ., %l[label] - . \n\t"
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" " RISCV_PTR " %0 - . \n\t"
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" .popsection \n\t"
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: : "i"(&((char *)key)[branch]) : : label);
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return false;
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label:
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return true;
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}
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static __always_inline bool arch_static_branch_jump(struct static_key * const key,
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const bool branch)
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{
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asm_volatile_goto(
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" .align 2 \n\t"
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" .option push \n\t"
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" .option norelax \n\t"
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" .option norvc \n\t"
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"1: jal zero, %l[label] \n\t"
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" .option pop \n\t"
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" .pushsection __jump_table, \"aw\" \n\t"
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" .align " RISCV_LGPTR " \n\t"
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" .long 1b - ., %l[label] - . \n\t"
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" " RISCV_PTR " %0 - . \n\t"
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" .popsection \n\t"
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: : "i"(&((char *)key)[branch]) : : label);
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return false;
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label:
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return true;
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}
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#endif /* __ASSEMBLY__ */
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#endif /* __ASM_JUMP_LABEL_H */
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