1#ifndef _ASM_S390_KPROBES_H
2#define _ASM_S390_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, 2006
21 *
22 * 2002-Oct	Created by Vamsi Krishna S <vamsi_krishna@in.ibm.com> Kernel
23 *		Probes initial implementation ( includes suggestions from
24 *		Rusty Russell).
25 * 2004-Nov	Modified for PPC64 by Ananth N Mavinakayanahalli
26 *		<ananth@in.ibm.com>
27 * 2005-Dec	Used as a template for s390 by Mike Grundy
28 *		<grundym@us.ibm.com>
29 */
30#include <linux/types.h>
31#include <linux/ptrace.h>
32#include <linux/percpu.h>
33
34#define  __ARCH_WANT_KPROBES_INSN_SLOT
35struct pt_regs;
36struct kprobe;
37
38typedef u16 kprobe_opcode_t;
39#define BREAKPOINT_INSTRUCTION	0x0002
40
41/* Maximum instruction size is 3 (16bit) halfwords: */
42#define MAX_INSN_SIZE		0x0003
43#define MAX_STACK_SIZE		64
44#define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
45	(((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR))) \
46	? (MAX_STACK_SIZE) \
47	: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
48
49#define JPROBE_ENTRY(pentry) (kprobe_opcode_t *)(pentry)
50
51#define ARCH_SUPPORTS_KRETPROBES
52#define ARCH_INACTIVE_KPROBE_COUNT 0
53
54#define KPROBE_SWAP_INST	0x10
55
56#define FIXUP_PSW_NORMAL	0x08
57#define FIXUP_BRANCH_NOT_TAKEN	0x04
58#define FIXUP_RETURN_REGISTER	0x02
59#define FIXUP_NOT_REQUIRED	0x01
60
61/* Architecture specific copy of original instruction */
62struct arch_specific_insn {
63	/* copy of original instruction */
64	kprobe_opcode_t *insn;
65	int fixup;
66	int ilen;
67	int reg;
68};
69
70struct ins_replace_args {
71	kprobe_opcode_t *ptr;
72	kprobe_opcode_t old;
73	kprobe_opcode_t new;
74};
75struct prev_kprobe {
76	struct kprobe *kp;
77	unsigned long status;
78	unsigned long saved_psw;
79	unsigned long kprobe_saved_imask;
80	unsigned long kprobe_saved_ctl[3];
81};
82
83/* per-cpu kprobe control block */
84struct kprobe_ctlblk {
85	unsigned long kprobe_status;
86	unsigned long kprobe_saved_imask;
87	unsigned long kprobe_saved_ctl[3];
88	struct pt_regs jprobe_saved_regs;
89	unsigned long jprobe_saved_r14;
90	unsigned long jprobe_saved_r15;
91	struct prev_kprobe prev_kprobe;
92	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
93};
94
95void arch_remove_kprobe(struct kprobe *p);
96void kretprobe_trampoline(void);
97int  is_prohibited_opcode(kprobe_opcode_t *instruction);
98void get_instruction_type(struct arch_specific_insn *ainsn);
99
100int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
101int kprobe_exceptions_notify(struct notifier_block *self,
102	unsigned long val, void *data);
103
104#define flush_insn_slot(p)	do { } while (0)
105
106#endif	/* _ASM_S390_KPROBES_H */
107