xref: /openbmc/linux/arch/s390/include/asm/kprobes.h (revision bc5aa3a0)
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 #define __ARCH_WANT_KPROBES_INSN_SLOT
35 
36 struct pt_regs;
37 struct kprobe;
38 
39 typedef u16 kprobe_opcode_t;
40 #define BREAKPOINT_INSTRUCTION	0x0002
41 
42 /* Maximum instruction size is 3 (16bit) halfwords: */
43 #define MAX_INSN_SIZE		0x0003
44 #define MAX_STACK_SIZE		64
45 #define MIN_STACK_SIZE(ADDR) (((MAX_STACK_SIZE) < \
46 	(((unsigned long)task_stack_page(current)) + THREAD_SIZE - (ADDR))) \
47 	? (MAX_STACK_SIZE) \
48 	: (((unsigned long)task_stack_page(current)) + THREAD_SIZE - (ADDR)))
49 
50 #define kretprobe_blacklist_size 0
51 
52 #define KPROBE_SWAP_INST	0x10
53 
54 #define FIXUP_PSW_NORMAL	0x08
55 #define FIXUP_BRANCH_NOT_TAKEN	0x04
56 #define FIXUP_RETURN_REGISTER	0x02
57 #define FIXUP_NOT_REQUIRED	0x01
58 
59 /* Architecture specific copy of original instruction */
60 struct arch_specific_insn {
61 	/* copy of original instruction */
62 	kprobe_opcode_t *insn;
63 	unsigned int is_ftrace_insn : 1;
64 };
65 
66 struct prev_kprobe {
67 	struct kprobe *kp;
68 	unsigned long status;
69 };
70 
71 /* per-cpu kprobe control block */
72 struct kprobe_ctlblk {
73 	unsigned long kprobe_status;
74 	unsigned long kprobe_saved_imask;
75 	unsigned long kprobe_saved_ctl[3];
76 	struct prev_kprobe prev_kprobe;
77 	struct pt_regs jprobe_saved_regs;
78 	kprobe_opcode_t jprobes_stack[MAX_STACK_SIZE];
79 };
80 
81 void arch_remove_kprobe(struct kprobe *p);
82 void kretprobe_trampoline(void);
83 
84 int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
85 int kprobe_exceptions_notify(struct notifier_block *self,
86 	unsigned long val, void *data);
87 
88 int probe_is_prohibited_opcode(u16 *insn);
89 int probe_get_fixup_type(u16 *insn);
90 int probe_is_insn_relative_long(u16 *insn);
91 
92 #define flush_insn_slot(p)	do { } while (0)
93 
94 #endif	/* _ASM_S390_KPROBES_H */
95