// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2022 Loongson Technology Corporation Limited */ #include <linux/kernel.h> #include <asm/unwind.h> unsigned long unwind_get_return_address(struct unwind_state *state) { if (unwind_done(state)) return 0; else if (state->first) return state->pc; return *(unsigned long *)(state->sp); } EXPORT_SYMBOL_GPL(unwind_get_return_address); void unwind_start(struct unwind_state *state, struct task_struct *task, struct pt_regs *regs) { memset(state, 0, sizeof(*state)); if (regs) { state->sp = regs->regs[3]; state->pc = regs->csr_era; } state->task = task; state->first = true; get_stack_info(state->sp, state->task, &state->stack_info); if (!unwind_done(state) && !__kernel_text_address(state->pc)) unwind_next_frame(state); } EXPORT_SYMBOL_GPL(unwind_start); bool unwind_next_frame(struct unwind_state *state) { struct stack_info *info = &state->stack_info; unsigned long addr; if (unwind_done(state)) return false; if (state->first) state->first = false; do { for (state->sp += sizeof(unsigned long); state->sp < info->end; state->sp += sizeof(unsigned long)) { addr = *(unsigned long *)(state->sp); if (__kernel_text_address(addr)) return true; } state->sp = info->next_sp; } while (!get_stack_info(state->sp, state->task, info)); return false; } EXPORT_SYMBOL_GPL(unwind_next_frame);