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// SPDX-License-Identifier: GPL-2.0-only
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/*
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 * Copyright (C) 2025 Chen Miao
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 *
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 * Based on arch/arm/kernel/jump_label.c
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 */
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#include <linux/jump_label.h>
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#include <linux/kernel.h>
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#include <linux/memory.h>
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#include <asm/bug.h>
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#include <asm/cacheflush.h>
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#include <asm/text-patching.h>
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bool arch_jump_label_transform_queue(struct jump_entry *entry,
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				     enum jump_label_type type)
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{
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	void *addr = (void *)jump_entry_code(entry);
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	u32 insn;
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	if (type == JUMP_LABEL_JMP) {
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		long offset;
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		offset = jump_entry_target(entry) - jump_entry_code(entry);
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		/*
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		 * The actual maximum range of the l.j instruction's offset is -134,217,728
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		 * ~ 134,217,724 (sign 26-bit imm).
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		 * For the original jump range, we need to right-shift N by 2 to obtain the
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		 * instruction's offset.
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		 */
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		WARN_ON_ONCE(offset < -134217728 || offset > 134217724);
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		/* 26bit imm mask */
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		offset = (offset >> 2) & 0x03ffffff;
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		insn = offset;
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	} else {
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		insn = OPENRISC_INSN_NOP;
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	}
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	if (early_boot_irqs_disabled)
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		copy_to_kernel_nofault(addr, &insn, sizeof(insn));
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	else
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		patch_insn_write(addr, insn);
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	return true;
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}
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void arch_jump_label_transform_apply(void)
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{
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	kick_all_cpus_sync();
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}
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