1 #ifndef _ASM_X86_KPROBES_H 2 #define _ASM_X86_KPROBES_H 3 /* 4 * Kernel Probes (KProbes) 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (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, write to the Free Software 18 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 19 * 20 * Copyright (C) IBM Corporation, 2002, 2004 21 * 22 * See arch/x86/kernel/kprobes.c for x86 kprobes history. 23 */ 24 #include <linux/types.h> 25 #include <linux/ptrace.h> 26 #include <linux/percpu.h> 27 #include <asm/insn.h> 28 29 #define __ARCH_WANT_KPROBES_INSN_SLOT 30 #define ARCH_SUPPORTS_KPROBES_ON_FTRACE 31 32 struct pt_regs; 33 struct kprobe; 34 35 typedef u8 kprobe_opcode_t; 36 #define BREAKPOINT_INSTRUCTION 0xcc 37 #define RELATIVEJUMP_OPCODE 0xe9 38 #define RELATIVEJUMP_SIZE 5 39 #define RELATIVECALL_OPCODE 0xe8 40 #define RELATIVE_ADDR_SIZE 4 41 #define MAX_STACK_SIZE 64 42 #define MIN_STACK_SIZE(ADDR) \ 43 (((MAX_STACK_SIZE) < (((unsigned long)current_thread_info()) + \ 44 THREAD_SIZE - (unsigned long)(ADDR))) \ 45 ? (MAX_STACK_SIZE) \ 46 : (((unsigned long)current_thread_info()) + \ 47 THREAD_SIZE - (unsigned long)(ADDR))) 48 49 #define flush_insn_slot(p) do { } while (0) 50 51 /* optinsn template addresses */ 52 extern kprobe_opcode_t optprobe_template_entry; 53 extern kprobe_opcode_t optprobe_template_val; 54 extern kprobe_opcode_t optprobe_template_call; 55 extern kprobe_opcode_t optprobe_template_end; 56 #define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE) 57 #define MAX_OPTINSN_SIZE \ 58 (((unsigned long)&optprobe_template_end - \ 59 (unsigned long)&optprobe_template_entry) + \ 60 MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE) 61 62 extern const int kretprobe_blacklist_size; 63 64 void arch_remove_kprobe(struct kprobe *p); 65 void kretprobe_trampoline(void); 66 67 /* Architecture specific copy of original instruction*/ 68 struct arch_specific_insn { 69 /* copy of the original instruction */ 70 kprobe_opcode_t *insn; 71 /* 72 * boostable = -1: This instruction type is not boostable. 73 * boostable = 0: This instruction type is boostable. 74 * boostable = 1: This instruction has been boosted: we have 75 * added a relative jump after the instruction copy in insn, 76 * so no single-step and fixup are needed (unless there's 77 * a post_handler or break_handler). 78 */ 79 int boostable; 80 bool if_modifier; 81 }; 82 83 struct arch_optimized_insn { 84 /* copy of the original instructions */ 85 kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE]; 86 /* detour code buffer */ 87 kprobe_opcode_t *insn; 88 /* the size of instructions copied to detour code buffer */ 89 size_t size; 90 }; 91 92 /* Return true (!0) if optinsn is prepared for optimization. */ 93 static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn) 94 { 95 return optinsn->size; 96 } 97 98 struct prev_kprobe { 99 struct kprobe *kp; 100 unsigned long status; 101 unsigned long old_flags; 102 unsigned long saved_flags; 103 }; 104 105 /* per-cpu kprobe control block */ 106 struct kprobe_ctlblk { 107 unsigned long kprobe_status; 108 unsigned long kprobe_old_flags; 109 unsigned long kprobe_saved_flags; 110 unsigned long *jprobe_saved_sp; 111 struct pt_regs jprobe_saved_regs; 112 kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE]; 113 struct prev_kprobe prev_kprobe; 114 }; 115 116 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr); 117 extern int kprobe_exceptions_notify(struct notifier_block *self, 118 unsigned long val, void *data); 119 #endif /* _ASM_X86_KPROBES_H */ 120