1 #ifndef _ASM_POWERPC_KPROBES_H 2 #define _ASM_POWERPC_KPROBES_H 3 4 #include <asm-generic/kprobes.h> 5 6 #ifdef __KERNEL__ 7 /* 8 * Kernel Probes (KProbes) 9 * 10 * This program is free software; you can redistribute it and/or modify 11 * it under the terms of the GNU General Public License as published by 12 * the Free Software Foundation; either version 2 of the License, or 13 * (at your option) any later version. 14 * 15 * This program is distributed in the hope that it will be useful, 16 * but WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 * GNU General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 23 * 24 * Copyright (C) IBM Corporation, 2002, 2004 25 * 26 * 2002-Oct Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel 27 * Probes initial implementation ( includes suggestions from 28 * Rusty Russell). 29 * 2004-Nov Modified for PPC64 by Ananth N Mavinakayanahalli 30 * <ananth@in.ibm.com> 31 */ 32 #include <linux/types.h> 33 #include <linux/ptrace.h> 34 #include <linux/percpu.h> 35 #include <linux/module.h> 36 #include <asm/probes.h> 37 #include <asm/code-patching.h> 38 39 #ifdef CONFIG_KPROBES 40 #define __ARCH_WANT_KPROBES_INSN_SLOT 41 42 struct pt_regs; 43 struct kprobe; 44 45 typedef ppc_opcode_t kprobe_opcode_t; 46 47 extern kprobe_opcode_t optinsn_slot; 48 49 /* Optinsn template address */ 50 extern kprobe_opcode_t optprobe_template_entry[]; 51 extern kprobe_opcode_t optprobe_template_op_address[]; 52 extern kprobe_opcode_t optprobe_template_call_handler[]; 53 extern kprobe_opcode_t optprobe_template_insn[]; 54 extern kprobe_opcode_t optprobe_template_call_emulate[]; 55 extern kprobe_opcode_t optprobe_template_ret[]; 56 extern kprobe_opcode_t optprobe_template_end[]; 57 58 /* Fixed instruction size for powerpc */ 59 #define MAX_INSN_SIZE 1 60 #define MAX_OPTIMIZED_LENGTH sizeof(kprobe_opcode_t) /* 4 bytes */ 61 #define MAX_OPTINSN_SIZE (optprobe_template_end - optprobe_template_entry) 62 #define RELATIVEJUMP_SIZE sizeof(kprobe_opcode_t) /* 4 bytes */ 63 64 #ifdef PPC64_ELF_ABI_v2 65 /* PPC64 ABIv2 needs local entry point */ 66 #define kprobe_lookup_name(name, addr) \ 67 { \ 68 addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ 69 if (addr) \ 70 addr = (kprobe_opcode_t *)ppc_function_entry(addr); \ 71 } 72 #elif defined(PPC64_ELF_ABI_v1) 73 /* 74 * 64bit powerpc ABIv1 uses function descriptors: 75 * - Check for the dot variant of the symbol first. 76 * - If that fails, try looking up the symbol provided. 77 * 78 * This ensures we always get to the actual symbol and not the descriptor. 79 * Also handle <module:symbol> format. 80 */ 81 #define kprobe_lookup_name(name, addr) \ 82 { \ 83 char dot_name[MODULE_NAME_LEN + 1 + KSYM_NAME_LEN]; \ 84 const char *modsym; \ 85 bool dot_appended = false; \ 86 if ((modsym = strchr(name, ':')) != NULL) { \ 87 modsym++; \ 88 if (*modsym != '\0' && *modsym != '.') { \ 89 /* Convert to <module:.symbol> */ \ 90 strncpy(dot_name, name, modsym - name); \ 91 dot_name[modsym - name] = '.'; \ 92 dot_name[modsym - name + 1] = '\0'; \ 93 strncat(dot_name, modsym, \ 94 sizeof(dot_name) - (modsym - name) - 2);\ 95 dot_appended = true; \ 96 } else { \ 97 dot_name[0] = '\0'; \ 98 strncat(dot_name, name, sizeof(dot_name) - 1); \ 99 } \ 100 } else if (name[0] != '.') { \ 101 dot_name[0] = '.'; \ 102 dot_name[1] = '\0'; \ 103 strncat(dot_name, name, KSYM_NAME_LEN - 2); \ 104 dot_appended = true; \ 105 } else { \ 106 dot_name[0] = '\0'; \ 107 strncat(dot_name, name, KSYM_NAME_LEN - 1); \ 108 } \ 109 addr = (kprobe_opcode_t *)kallsyms_lookup_name(dot_name); \ 110 if (!addr && dot_appended) { \ 111 /* Let's try the original non-dot symbol lookup */ \ 112 addr = (kprobe_opcode_t *)kallsyms_lookup_name(name); \ 113 } \ 114 } 115 #endif 116 117 #define flush_insn_slot(p) do { } while (0) 118 #define kretprobe_blacklist_size 0 119 120 void kretprobe_trampoline(void); 121 extern void arch_remove_kprobe(struct kprobe *p); 122 123 /* Architecture specific copy of original instruction */ 124 struct arch_specific_insn { 125 /* copy of original instruction */ 126 kprobe_opcode_t *insn; 127 /* 128 * Set in kprobes code, initially to 0. If the instruction can be 129 * eumulated, this is set to 1, if not, to -1. 130 */ 131 int boostable; 132 }; 133 134 struct prev_kprobe { 135 struct kprobe *kp; 136 unsigned long status; 137 unsigned long saved_msr; 138 }; 139 140 /* per-cpu kprobe control block */ 141 struct kprobe_ctlblk { 142 unsigned long kprobe_status; 143 unsigned long kprobe_saved_msr; 144 struct pt_regs jprobe_saved_regs; 145 struct prev_kprobe prev_kprobe; 146 }; 147 148 struct arch_optimized_insn { 149 kprobe_opcode_t copied_insn[1]; 150 /* detour buffer */ 151 kprobe_opcode_t *insn; 152 }; 153 154 extern int kprobe_exceptions_notify(struct notifier_block *self, 155 unsigned long val, void *data); 156 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr); 157 extern int kprobe_handler(struct pt_regs *regs); 158 extern int kprobe_post_handler(struct pt_regs *regs); 159 #else 160 static inline int kprobe_handler(struct pt_regs *regs) { return 0; } 161 static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; } 162 #endif /* CONFIG_KPROBES */ 163 #endif /* __KERNEL__ */ 164 #endif /* _ASM_POWERPC_KPROBES_H */ 165