xref: /openbmc/linux/arch/mips/include/asm/kprobes.h (revision 9cfc5c90)
1 /*
2  *  Kernel Probes (KProbes)
3  *  include/asm-mips/kprobes.h
4  *
5  *  Copyright 2006 Sony Corp.
6  *  Copyright 2010 Cavium Networks
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU General Public License as published by
10  *  the Free Software Foundation; version 2 of the License.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 #ifndef _ASM_KPROBES_H
23 #define _ASM_KPROBES_H
24 
25 #include <linux/ptrace.h>
26 #include <linux/types.h>
27 
28 #include <asm/cacheflush.h>
29 #include <asm/kdebug.h>
30 #include <asm/inst.h>
31 
32 #define	 __ARCH_WANT_KPROBES_INSN_SLOT
33 
34 struct kprobe;
35 struct pt_regs;
36 
37 typedef union mips_instruction kprobe_opcode_t;
38 
39 #define MAX_INSN_SIZE 2
40 
41 #define flush_insn_slot(p)						\
42 do {									\
43 	flush_icache_range((unsigned long)p->addr,			\
44 			   (unsigned long)p->addr +			\
45 			   (MAX_INSN_SIZE * sizeof(kprobe_opcode_t)));	\
46 } while (0)
47 
48 
49 #define kretprobe_blacklist_size 0
50 
51 void arch_remove_kprobe(struct kprobe *p);
52 
53 /* Architecture specific copy of original instruction*/
54 struct arch_specific_insn {
55 	/* copy of the original instruction */
56 	kprobe_opcode_t *insn;
57 };
58 
59 struct prev_kprobe {
60 	struct kprobe *kp;
61 	unsigned long status;
62 	unsigned long old_SR;
63 	unsigned long saved_SR;
64 	unsigned long saved_epc;
65 };
66 
67 #define MAX_JPROBES_STACK_SIZE 128
68 #define MAX_JPROBES_STACK_ADDR \
69 	(((unsigned long)current_thread_info()) + THREAD_SIZE - 32 - sizeof(struct pt_regs))
70 
71 #define MIN_JPROBES_STACK_SIZE(ADDR)					\
72 	((((ADDR) + MAX_JPROBES_STACK_SIZE) > MAX_JPROBES_STACK_ADDR)	\
73 		? MAX_JPROBES_STACK_ADDR - (ADDR)			\
74 		: MAX_JPROBES_STACK_SIZE)
75 
76 
77 #define SKIP_DELAYSLOT 0x0001
78 
79 /* per-cpu kprobe control block */
80 struct kprobe_ctlblk {
81 	unsigned long kprobe_status;
82 	unsigned long kprobe_old_SR;
83 	unsigned long kprobe_saved_SR;
84 	unsigned long kprobe_saved_epc;
85 	unsigned long jprobe_saved_sp;
86 	struct pt_regs jprobe_saved_regs;
87 	/* Per-thread fields, used while emulating branches */
88 	unsigned long flags;
89 	unsigned long target_epc;
90 	u8 jprobes_stack[MAX_JPROBES_STACK_SIZE];
91 	struct prev_kprobe prev_kprobe;
92 };
93 
94 extern int kprobe_exceptions_notify(struct notifier_block *self,
95 				    unsigned long val, void *data);
96 
97 #endif				/* _ASM_KPROBES_H */
98