xref: /openbmc/linux/arch/arm/include/asm/kprobes.h (revision a8da474e)
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/notifier.h>
22 
23 #define __ARCH_WANT_KPROBES_INSN_SLOT
24 #define MAX_INSN_SIZE			2
25 
26 #define flush_insn_slot(p)		do { } while (0)
27 #define kretprobe_blacklist_size	0
28 
29 typedef u32 kprobe_opcode_t;
30 struct kprobe;
31 #include <asm/probes.h>
32 
33 #define	arch_specific_insn	arch_probes_insn
34 
35 struct prev_kprobe {
36 	struct kprobe *kp;
37 	unsigned int status;
38 };
39 
40 /* per-cpu kprobe control block */
41 struct kprobe_ctlblk {
42 	unsigned int kprobe_status;
43 	struct prev_kprobe prev_kprobe;
44 	struct pt_regs jprobe_saved_regs;
45 	char jprobes_stack[MAX_STACK_SIZE];
46 };
47 
48 void arch_remove_kprobe(struct kprobe *);
49 int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
50 int kprobe_exceptions_notify(struct notifier_block *self,
51 			     unsigned long val, void *data);
52 
53 /* optinsn template addresses */
54 extern __visible kprobe_opcode_t optprobe_template_entry;
55 extern __visible kprobe_opcode_t optprobe_template_val;
56 extern __visible kprobe_opcode_t optprobe_template_call;
57 extern __visible kprobe_opcode_t optprobe_template_end;
58 extern __visible kprobe_opcode_t optprobe_template_sub_sp;
59 extern __visible kprobe_opcode_t optprobe_template_add_sp;
60 extern __visible kprobe_opcode_t optprobe_template_restore_begin;
61 extern __visible kprobe_opcode_t optprobe_template_restore_orig_insn;
62 extern __visible kprobe_opcode_t optprobe_template_restore_end;
63 
64 #define MAX_OPTIMIZED_LENGTH	4
65 #define MAX_OPTINSN_SIZE				\
66 	((unsigned long)&optprobe_template_end -	\
67 	 (unsigned long)&optprobe_template_entry)
68 #define RELATIVEJUMP_SIZE	4
69 
70 struct arch_optimized_insn {
71 	/*
72 	 * copy of the original instructions.
73 	 * Different from x86, ARM kprobe_opcode_t is u32.
74 	 */
75 #define MAX_COPIED_INSN	DIV_ROUND_UP(RELATIVEJUMP_SIZE, sizeof(kprobe_opcode_t))
76 	kprobe_opcode_t copied_insn[MAX_COPIED_INSN];
77 	/* detour code buffer */
78 	kprobe_opcode_t *insn;
79 	/*
80 	 * We always copy one instruction on ARM,
81 	 * so size will always be 4, and unlike x86, there is no
82 	 * need for a size field.
83 	 */
84 };
85 
86 #endif /* _ARM_KPROBES_H */
87