xref: /openbmc/linux/arch/s390/include/asm/kprobes.h (revision 95e9fd10)
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 IBM Corp. 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 struct pt_regs;
35 struct kprobe;
36 
37 typedef u16 kprobe_opcode_t;
38 #define BREAKPOINT_INSTRUCTION	0x0002
39 
40 /* Maximum instruction size is 3 (16bit) halfwords: */
41 #define MAX_INSN_SIZE		0x0003
42 #define MAX_STACK_SIZE		64
43 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
44 	(((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR))) \
45 	? (MAX_STACK_SIZE) \
46 	: (((unsigned long)current_thread_info()) + THREAD_SIZE - (ADDR)))
47 
48 #define kretprobe_blacklist_size 0
49 
50 #define KPROBE_SWAP_INST	0x10
51 
52 #define FIXUP_PSW_NORMAL	0x08
53 #define FIXUP_BRANCH_NOT_TAKEN	0x04
54 #define FIXUP_RETURN_REGISTER	0x02
55 #define FIXUP_NOT_REQUIRED	0x01
56 
57 /* Architecture specific copy of original instruction */
58 struct arch_specific_insn {
59 	/* copy of original instruction */
60 	kprobe_opcode_t insn[MAX_INSN_SIZE];
61 };
62 
63 struct prev_kprobe {
64 	struct kprobe *kp;
65 	unsigned long status;
66 };
67 
68 /* per-cpu kprobe control block */
69 struct kprobe_ctlblk {
70 	unsigned long kprobe_status;
71 	unsigned long kprobe_saved_imask;
72 	unsigned long kprobe_saved_ctl[3];
73 	struct prev_kprobe prev_kprobe;
74 	struct pt_regs jprobe_saved_regs;
75 	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
76 };
77 
78 void arch_remove_kprobe(struct kprobe *p);
79 void kretprobe_trampoline(void);
80 
81 int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
82 int kprobe_exceptions_notify(struct notifier_block *self,
83 	unsigned long val, void *data);
84 
85 #define flush_insn_slot(p)	do { } while (0)
86 
87 #endif	/* _ASM_S390_KPROBES_H */
88