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