1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * livepatch.h - powerpc-specific Kernel Live Patching Core
4  *
5  * Copyright (C) 2015-2016, SUSE, IBM Corp.
6  */
7 #ifndef _ASM_POWERPC_LIVEPATCH_H
8 #define _ASM_POWERPC_LIVEPATCH_H
9 
10 #include <linux/module.h>
11 #include <linux/ftrace.h>
12 #include <linux/sched/task_stack.h>
13 
14 #ifdef CONFIG_LIVEPATCH
15 static inline void klp_arch_set_pc(struct ftrace_regs *fregs, unsigned long ip)
16 {
17 	struct pt_regs *regs = ftrace_get_regs(fregs);
18 
19 	regs_set_return_ip(regs, ip);
20 }
21 
22 #define klp_get_ftrace_location klp_get_ftrace_location
23 static inline unsigned long klp_get_ftrace_location(unsigned long faddr)
24 {
25 	/*
26 	 * Live patch works only with -mprofile-kernel on PPC. In this case,
27 	 * the ftrace location is always within the first 16 bytes.
28 	 */
29 	return ftrace_location_range(faddr, faddr + 16);
30 }
31 
32 static inline void klp_init_thread_info(struct task_struct *p)
33 {
34 	/* + 1 to account for STACK_END_MAGIC */
35 	task_thread_info(p)->livepatch_sp = end_of_stack(p) + 1;
36 }
37 #else
38 static inline void klp_init_thread_info(struct task_struct *p) { }
39 #endif /* CONFIG_LIVEPATCH */
40 
41 #endif /* _ASM_POWERPC_LIVEPATCH_H */
42