1 /* 2 * livepatch.h - powerpc-specific Kernel Live Patching Core 3 * 4 * Copyright (C) 2015-2016, SUSE, IBM Corp. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 2 9 * of the License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 #ifndef _ASM_POWERPC_LIVEPATCH_H 20 #define _ASM_POWERPC_LIVEPATCH_H 21 22 #include <linux/module.h> 23 #include <linux/ftrace.h> 24 25 #ifdef CONFIG_LIVEPATCH 26 static inline int klp_check_compiler_support(void) 27 { 28 return 0; 29 } 30 31 static inline int klp_write_module_reloc(struct module *mod, unsigned long 32 type, unsigned long loc, unsigned long value) 33 { 34 /* This requires infrastructure changes; we need the loadinfos. */ 35 return -ENOSYS; 36 } 37 38 static inline void klp_arch_set_pc(struct pt_regs *regs, unsigned long ip) 39 { 40 regs->nip = ip; 41 } 42 43 #define klp_get_ftrace_location klp_get_ftrace_location 44 static inline unsigned long klp_get_ftrace_location(unsigned long faddr) 45 { 46 /* 47 * Live patch works only with -mprofile-kernel on PPC. In this case, 48 * the ftrace location is always within the first 16 bytes. 49 */ 50 return ftrace_location_range(faddr, faddr + 16); 51 } 52 53 static inline void klp_init_thread_info(struct thread_info *ti) 54 { 55 /* + 1 to account for STACK_END_MAGIC */ 56 ti->livepatch_sp = (unsigned long *)(ti + 1) + 1; 57 } 58 #else 59 static void klp_init_thread_info(struct thread_info *ti) { } 60 #endif /* CONFIG_LIVEPATCH */ 61 62 #endif /* _ASM_POWERPC_LIVEPATCH_H */ 63