xref: /openbmc/linux/arch/arm/include/asm/kprobes.h (revision 4f6cce39)
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 <asm-generic/kprobes.h>
20 
21 #ifdef CONFIG_KPROBES
22 #include <linux/types.h>
23 #include <linux/ptrace.h>
24 #include <linux/notifier.h>
25 
26 #define __ARCH_WANT_KPROBES_INSN_SLOT
27 #define MAX_INSN_SIZE			2
28 
29 #define flush_insn_slot(p)		do { } while (0)
30 #define kretprobe_blacklist_size	0
31 
32 typedef u32 kprobe_opcode_t;
33 struct kprobe;
34 #include <asm/probes.h>
35 
36 #define	arch_specific_insn	arch_probes_insn
37 
38 struct prev_kprobe {
39 	struct kprobe *kp;
40 	unsigned int status;
41 };
42 
43 /* per-cpu kprobe control block */
44 struct kprobe_ctlblk {
45 	unsigned int kprobe_status;
46 	struct prev_kprobe prev_kprobe;
47 	struct pt_regs jprobe_saved_regs;
48 	char jprobes_stack[MAX_STACK_SIZE];
49 };
50 
51 void arch_remove_kprobe(struct kprobe *);
52 int kprobe_fault_handler(struct pt_regs *regs, unsigned int fsr);
53 int kprobe_exceptions_notify(struct notifier_block *self,
54 			     unsigned long val, void *data);
55 
56 /* optinsn template addresses */
57 extern __visible kprobe_opcode_t optprobe_template_entry;
58 extern __visible kprobe_opcode_t optprobe_template_val;
59 extern __visible kprobe_opcode_t optprobe_template_call;
60 extern __visible kprobe_opcode_t optprobe_template_end;
61 extern __visible kprobe_opcode_t optprobe_template_sub_sp;
62 extern __visible kprobe_opcode_t optprobe_template_add_sp;
63 extern __visible kprobe_opcode_t optprobe_template_restore_begin;
64 extern __visible kprobe_opcode_t optprobe_template_restore_orig_insn;
65 extern __visible kprobe_opcode_t optprobe_template_restore_end;
66 
67 #define MAX_OPTIMIZED_LENGTH	4
68 #define MAX_OPTINSN_SIZE				\
69 	((unsigned long)&optprobe_template_end -	\
70 	 (unsigned long)&optprobe_template_entry)
71 #define RELATIVEJUMP_SIZE	4
72 
73 struct arch_optimized_insn {
74 	/*
75 	 * copy of the original instructions.
76 	 * Different from x86, ARM kprobe_opcode_t is u32.
77 	 */
78 #define MAX_COPIED_INSN	DIV_ROUND_UP(RELATIVEJUMP_SIZE, sizeof(kprobe_opcode_t))
79 	kprobe_opcode_t copied_insn[MAX_COPIED_INSN];
80 	/* detour code buffer */
81 	kprobe_opcode_t *insn;
82 	/*
83 	 * We always copy one instruction on ARM,
84 	 * so size will always be 4, and unlike x86, there is no
85 	 * need for a size field.
86 	 */
87 };
88 
89 #endif /* CONFIG_KPROBES */
90 #endif /* _ARM_KPROBES_H */
91