xref: /openbmc/linux/arch/s390/include/asm/kprobes.h (revision b627b4ed)
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
35 struct pt_regs;
36 struct kprobe;
37 
38 typedef 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 kretprobe_blacklist_size 0
50 
51 #define KPROBE_SWAP_INST	0x10
52 
53 #define FIXUP_PSW_NORMAL	0x08
54 #define FIXUP_BRANCH_NOT_TAKEN	0x04
55 #define FIXUP_RETURN_REGISTER	0x02
56 #define FIXUP_NOT_REQUIRED	0x01
57 
58 /* Architecture specific copy of original instruction */
59 struct arch_specific_insn {
60 	/* copy of original instruction */
61 	kprobe_opcode_t *insn;
62 	int fixup;
63 	int ilen;
64 	int reg;
65 };
66 
67 struct ins_replace_args {
68 	kprobe_opcode_t *ptr;
69 	kprobe_opcode_t old;
70 	kprobe_opcode_t new;
71 };
72 struct prev_kprobe {
73 	struct kprobe *kp;
74 	unsigned long status;
75 	unsigned long saved_psw;
76 	unsigned long kprobe_saved_imask;
77 	unsigned long kprobe_saved_ctl[3];
78 };
79 
80 /* per-cpu kprobe control block */
81 struct kprobe_ctlblk {
82 	unsigned long kprobe_status;
83 	unsigned long kprobe_saved_imask;
84 	unsigned long kprobe_saved_ctl[3];
85 	struct pt_regs jprobe_saved_regs;
86 	unsigned long jprobe_saved_r14;
87 	unsigned long jprobe_saved_r15;
88 	struct prev_kprobe prev_kprobe;
89 	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
90 };
91 
92 void arch_remove_kprobe(struct kprobe *p);
93 void kretprobe_trampoline(void);
94 int  is_prohibited_opcode(kprobe_opcode_t *instruction);
95 void get_instruction_type(struct arch_specific_insn *ainsn);
96 
97 int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
98 int kprobe_exceptions_notify(struct notifier_block *self,
99 	unsigned long val, void *data);
100 
101 #define flush_insn_slot(p)	do { } while (0)
102 
103 #endif	/* _ASM_S390_KPROBES_H */
104