xref: /linux/arch/arm/include/asm/kprobes.h (revision 6de9c70882ecdee63a652d493bf2353963bd4c22)
1 /*
2  * arch/arm/include/asm/kprobes.h
3  *
4  * Copyright (C) 2006, 2007 Motorola Inc.
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 version 2 as
8  * published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13  * General Public License for more details.
14  */
15 
16 #ifndef _ARM_KPROBES_H
17 #define _ARM_KPROBES_H
18 
19 #include <linux/types.h>
20 #include <linux/ptrace.h>
21 #include <linux/percpu.h>
22 
23 #define __ARCH_WANT_KPROBES_INSN_SLOT
24 #define MAX_INSN_SIZE			2
25 #define MAX_STACK_SIZE			64	/* 32 would probably be OK */
26 
27 /*
28  * This undefined instruction must be unique and
29  * reserved solely for kprobes' use.
30  */
31 #define KPROBE_BREAKPOINT_INSTRUCTION	0xe7f001f8
32 
33 #define regs_return_value(regs)		((regs)->ARM_r0)
34 #define flush_insn_slot(p)		do { } while (0)
35 #define kretprobe_blacklist_size	0
36 
37 typedef u32 kprobe_opcode_t;
38 
39 struct kprobe;
40 typedef void (kprobe_insn_handler_t)(struct kprobe *, struct pt_regs *);
41 
42 /* Architecture specific copy of original instruction. */
43 struct arch_specific_insn {
44 	kprobe_opcode_t		*insn;
45 	kprobe_insn_handler_t	*insn_handler;
46 };
47 
48 struct prev_kprobe {
49 	struct kprobe *kp;
50 	unsigned int status;
51 };
52 
53 /* per-cpu kprobe control block */
54 struct kprobe_ctlblk {
55 	unsigned int kprobe_status;
56 	struct prev_kprobe prev_kprobe;
57 	struct pt_regs jprobe_saved_regs;
58 	char jprobes_stack[MAX_STACK_SIZE];
59 };
60 
61 void arch_remove_kprobe(struct kprobe *);
62 void kretprobe_trampoline(void);
63 
64 int kprobe_trap_handler(struct pt_regs *regs, unsigned int instr);
65 int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
66 int kprobe_exceptions_notify(struct notifier_block *self,
67 			     unsigned long val, void *data);
68 
69 enum kprobe_insn {
70 	INSN_REJECTED,
71 	INSN_GOOD,
72 	INSN_GOOD_NO_SLOT
73 };
74 
75 enum kprobe_insn arm_kprobe_decode_insn(kprobe_opcode_t,
76 					struct arch_specific_insn *);
77 void __init arm_kprobe_decode_init(void);
78 
79 #endif /* _ARM_KPROBES_H */
80