xref: /openbmc/linux/arch/powerpc/include/asm/kprobes.h (revision be709d48)
1 #ifndef _ASM_POWERPC_KPROBES_H
2 #define _ASM_POWERPC_KPROBES_H
3 
4 #include <asm-generic/kprobes.h>
5 
6 #ifdef __KERNEL__
7 /*
8  *  Kernel Probes (KProbes)
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23  *
24  * Copyright (C) IBM Corporation, 2002, 2004
25  *
26  * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
27  *		Probes initial implementation ( includes suggestions from
28  *		Rusty Russell).
29  * 2004-Nov	Modified for PPC64 by Ananth N Mavinakayanahalli
30  *		<ananth@in.ibm.com>
31  */
32 #include <linux/types.h>
33 #include <linux/ptrace.h>
34 #include <linux/percpu.h>
35 #include <linux/module.h>
36 #include <asm/probes.h>
37 #include <asm/code-patching.h>
38 
39 #ifdef CONFIG_KPROBES
40 #define  __ARCH_WANT_KPROBES_INSN_SLOT
41 
42 struct pt_regs;
43 struct kprobe;
44 
45 typedef ppc_opcode_t kprobe_opcode_t;
46 
47 extern kprobe_opcode_t optinsn_slot;
48 
49 /* Optinsn template address */
50 extern kprobe_opcode_t optprobe_template_entry[];
51 extern kprobe_opcode_t optprobe_template_op_address[];
52 extern kprobe_opcode_t optprobe_template_call_handler[];
53 extern kprobe_opcode_t optprobe_template_insn[];
54 extern kprobe_opcode_t optprobe_template_call_emulate[];
55 extern kprobe_opcode_t optprobe_template_ret[];
56 extern kprobe_opcode_t optprobe_template_end[];
57 
58 /* Fixed instruction size for powerpc */
59 #define MAX_INSN_SIZE		1
60 #define MAX_OPTIMIZED_LENGTH	sizeof(kprobe_opcode_t)	/* 4 bytes */
61 #define MAX_OPTINSN_SIZE	(optprobe_template_end - optprobe_template_entry)
62 #define RELATIVEJUMP_SIZE	sizeof(kprobe_opcode_t)	/* 4 bytes */
63 
64 #define flush_insn_slot(p)	do { } while (0)
65 #define kretprobe_blacklist_size 0
66 
67 void kretprobe_trampoline(void);
68 extern void arch_remove_kprobe(struct kprobe *p);
69 
70 /* Architecture specific copy of original instruction */
71 struct arch_specific_insn {
72 	/* copy of original instruction */
73 	kprobe_opcode_t *insn;
74 	/*
75 	 * Set in kprobes code, initially to 0. If the instruction can be
76 	 * eumulated, this is set to 1, if not, to -1.
77 	 */
78 	int boostable;
79 };
80 
81 struct prev_kprobe {
82 	struct kprobe *kp;
83 	unsigned long status;
84 	unsigned long saved_msr;
85 };
86 
87 /* per-cpu kprobe control block */
88 struct kprobe_ctlblk {
89 	unsigned long kprobe_status;
90 	unsigned long kprobe_saved_msr;
91 	struct prev_kprobe prev_kprobe;
92 };
93 
94 struct arch_optimized_insn {
95 	kprobe_opcode_t copied_insn[1];
96 	/* detour buffer */
97 	kprobe_opcode_t *insn;
98 };
99 
100 extern int kprobe_exceptions_notify(struct notifier_block *self,
101 					unsigned long val, void *data);
102 extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
103 extern int kprobe_handler(struct pt_regs *regs);
104 extern int kprobe_post_handler(struct pt_regs *regs);
105 #else
106 static inline int kprobe_handler(struct pt_regs *regs) { return 0; }
107 static inline int kprobe_post_handler(struct pt_regs *regs) { return 0; }
108 #endif /* CONFIG_KPROBES */
109 #endif /* __KERNEL__ */
110 #endif	/* _ASM_POWERPC_KPROBES_H */
111