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
31 struct pt_regs;
32 struct kprobe;
33
34 typedef u8 kprobe_opcode_t;
35 #define BREAKPOINT_INSTRUCTION 0xcc
36 #define RELATIVEJUMP_OPCODE 0xe9
37 #define RELATIVEJUMP_SIZE 5
38 #define RELATIVECALL_OPCODE 0xe8
39 #define RELATIVE_ADDR_SIZE 4
40 #define MAX_STACK_SIZE 64
41 #define MIN_STACK_SIZE(ADDR) \
42 (((MAX_STACK_SIZE) < (((unsigned long)current_thread_info()) + \
43 THREAD_SIZE - (unsigned long)(ADDR))) \
44 ? (MAX_STACK_SIZE) \
45 : (((unsigned long)current_thread_info()) + \
46 THREAD_SIZE - (unsigned long)(ADDR)))
47
48 #define flush_insn_slot(p) do { } while (0)
49
50 /* optinsn template addresses */
51 extern kprobe_opcode_t optprobe_template_entry;
52 extern kprobe_opcode_t optprobe_template_val;
53 extern kprobe_opcode_t optprobe_template_call;
54 extern kprobe_opcode_t optprobe_template_end;
55 #define MAX_OPTIMIZED_LENGTH (MAX_INSN_SIZE + RELATIVE_ADDR_SIZE)
56 #define MAX_OPTINSN_SIZE \
57 (((unsigned long)&optprobe_template_end - \
58 (unsigned long)&optprobe_template_entry) + \
59 MAX_OPTIMIZED_LENGTH + RELATIVEJUMP_SIZE)
60
61 extern const int kretprobe_blacklist_size;
62
63 void arch_remove_kprobe(struct kprobe *p);
64 void kretprobe_trampoline(void);
65
66 /* Architecture specific copy of original instruction*/
67 struct arch_specific_insn {
68 /* copy of the original instruction */
69 kprobe_opcode_t *insn;
70 /*
71 * boostable = -1: This instruction type is not boostable.
72 * boostable = 0: This instruction type is boostable.
73 * boostable = 1: This instruction has been boosted: we have
74 * added a relative jump after the instruction copy in insn,
75 * so no single-step and fixup are needed (unless there's
76 * a post_handler or break_handler).
77 */
78 int boostable;
79 };
80
81 struct arch_optimized_insn {
82 /* copy of the original instructions */
83 kprobe_opcode_t copied_insn[RELATIVE_ADDR_SIZE];
84 /* detour code buffer */
85 kprobe_opcode_t *insn;
86 /* the size of instructions copied to detour code buffer */
87 size_t size;
88 };
89
90 /* Return true (!0) if optinsn is prepared for optimization. */
arch_prepared_optinsn(struct arch_optimized_insn * optinsn)91 static inline int arch_prepared_optinsn(struct arch_optimized_insn *optinsn)
92 {
93 return optinsn->size;
94 }
95
96 struct prev_kprobe {
97 struct kprobe *kp;
98 unsigned long status;
99 unsigned long old_flags;
100 unsigned long saved_flags;
101 };
102
103 /* per-cpu kprobe control block */
104 struct kprobe_ctlblk {
105 unsigned long kprobe_status;
106 unsigned long kprobe_old_flags;
107 unsigned long kprobe_saved_flags;
108 unsigned long *jprobe_saved_sp;
109 struct pt_regs jprobe_saved_regs;
110 kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
111 struct prev_kprobe prev_kprobe;
112 };
113
114 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
115 extern int kprobe_exceptions_notify(struct notifier_block *self,
116 unsigned long val, void *data);
117 #endif /* _ASM_X86_KPROBES_H */
118