1 // SPDX-License-Identifier: GPL-2.0
21 			return -EFAULT;  in ftrace_modify_code()
24 			return -EINVAL;  in ftrace_modify_code()
28 		return -EPERM;  in ftrace_modify_code()
36 	long offset = (long)addr - (long)pc;  in reachable_by_bl()  local
38 	return offset >= -SZ_128M && offset < SZ_128M;  in reachable_by_bl()
43 	struct plt_entry *plt = mod->arch.ftrace_trampolines;  in get_ftrace_plt()
57  * Due to the limited range of 'bl' instruction, modules may be placed too far
65 	unsigned long pc = rec->ip + LOONGARCH_INSN_SIZE;  in ftrace_find_callable_addr()
71 	 * ops->direct_call.  in ftrace_find_callable_addr()
77 	 * When the target is within range of the 'bl' instruction, use 'addr'  in ftrace_find_callable_addr()
78 	 * as-is and branch to that directly.  in ftrace_find_callable_addr()
85 	 * dealing with an out-of-range condition, we can assume it  in ftrace_find_callable_addr()
90 	 * retains its validity throughout the remainder of this code.  in ftrace_find_callable_addr()
123 	pc = rec->ip + LOONGARCH_INSN_SIZE;  in ftrace_modify_call()
126 		return -EINVAL;  in ftrace_modify_call()
129 		return -EINVAL;  in ftrace_modify_call()
153  * At runtime, we can replace nop with bl to enable ftrace call and replace bl
154  * with nop to disable ftrace call. The bl requires us to save the original RA
160  * +------------+------------------------+------------------------+
162  * | nop        | nop                    | bl       ftrace_caller |
175 	pc = rec->ip;  in ftrace_init_nop()
187 	pc = rec->ip + LOONGARCH_INSN_SIZE;  in ftrace_make_call()
190 		return -EINVAL;  in ftrace_make_call()
203 	pc = rec->ip + LOONGARCH_INSN_SIZE;  in ftrace_make_nop()
206 		return -EINVAL;  in ftrace_make_nop()
231 	if (unlikely(atomic_read(&current->tracing_graph_pause)))  in prepare_ftrace_return()
244 	struct pt_regs *regs = &arch_ftrace_regs(fregs)->regs;  in ftrace_graph_func()
245 	unsigned long *parent = (unsigned long *)&regs->regs[1];  in ftrace_graph_func()
249 	if (unlikely(atomic_read(&current->tracing_graph_pause)))  in ftrace_graph_func()
289 /* Ftrace callback handler for kprobes -- called under preepmt disabled */
322 		kcb->kprobe_status = KPROBE_HIT_ACTIVE;  in kprobe_ftrace_handler()
323 		if (!p->pre_handler || !p->pre_handler(p, regs)) {  in kprobe_ftrace_handler()
325 			 * Emulate singlestep (and also recover regs->csr_era)  in kprobe_ftrace_handler()
328 			instruction_pointer_set(regs, (unsigned long)p->addr + MCOUNT_INSN_SIZE);  in kprobe_ftrace_handler()
329 			if (unlikely(p->post_handler)) {  in kprobe_ftrace_handler()
330 				kcb->kprobe_status = KPROBE_HIT_SSDONE;  in kprobe_ftrace_handler()
331 				p->post_handler(p, regs, 0);  in kprobe_ftrace_handler()
337 		 * If pre_handler returns !0, it changes regs->csr_era. We have to  in kprobe_ftrace_handler()
349 	p->ainsn.insn = NULL;  in arch_prepare_kprobe_ftrace()