1/*
2 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8
9#include <linux/ptrace.h>
10#include <linux/tracehook.h>
11#include <linux/regset.h>
12#include <linux/unistd.h>
13#include <linux/elf.h>
14
15static struct callee_regs *task_callee_regs(struct task_struct *tsk)
16{
17	struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg;
18	return tmp;
19}
20
21static int genregs_get(struct task_struct *target,
22		       const struct user_regset *regset,
23		       unsigned int pos, unsigned int count,
24		       void *kbuf, void __user *ubuf)
25{
26	const struct pt_regs *ptregs = task_pt_regs(target);
27	const struct callee_regs *cregs = task_callee_regs(target);
28	int ret = 0;
29	unsigned int stop_pc_val;
30
31#define REG_O_CHUNK(START, END, PTR)	\
32	if (!ret)	\
33		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
34			offsetof(struct user_regs_struct, START), \
35			offsetof(struct user_regs_struct, END));
36
37#define REG_O_ONE(LOC, PTR)	\
38	if (!ret)		\
39		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
40			offsetof(struct user_regs_struct, LOC), \
41			offsetof(struct user_regs_struct, LOC) + 4);
42
43#define REG_O_ZERO(LOC)		\
44	if (!ret)		\
45		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
46			offsetof(struct user_regs_struct, LOC), \
47			offsetof(struct user_regs_struct, LOC) + 4);
48
49	REG_O_ZERO(pad);
50	REG_O_CHUNK(scratch, callee, ptregs);
51	REG_O_ZERO(pad2);
52	REG_O_CHUNK(callee, efa, cregs);
53	REG_O_CHUNK(efa, stop_pc, &target->thread.fault_address);
54
55	if (!ret) {
56		if (in_brkpt_trap(ptregs)) {
57			stop_pc_val = target->thread.fault_address;
58			pr_debug("\t\tstop_pc (brk-pt)\n");
59		} else {
60			stop_pc_val = ptregs->ret;
61			pr_debug("\t\tstop_pc (others)\n");
62		}
63
64		REG_O_ONE(stop_pc, &stop_pc_val);
65	}
66
67	return ret;
68}
69
70static int genregs_set(struct task_struct *target,
71		       const struct user_regset *regset,
72		       unsigned int pos, unsigned int count,
73		       const void *kbuf, const void __user *ubuf)
74{
75	const struct pt_regs *ptregs = task_pt_regs(target);
76	const struct callee_regs *cregs = task_callee_regs(target);
77	int ret = 0;
78
79#define REG_IN_CHUNK(FIRST, NEXT, PTR)	\
80	if (!ret)			\
81		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
82			(void *)(PTR), \
83			offsetof(struct user_regs_struct, FIRST), \
84			offsetof(struct user_regs_struct, NEXT));
85
86#define REG_IN_ONE(LOC, PTR)		\
87	if (!ret)			\
88		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
89			(void *)(PTR), \
90			offsetof(struct user_regs_struct, LOC), \
91			offsetof(struct user_regs_struct, LOC) + 4);
92
93#define REG_IGNORE_ONE(LOC)		\
94	if (!ret)			\
95		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
96			offsetof(struct user_regs_struct, LOC), \
97			offsetof(struct user_regs_struct, LOC) + 4);
98
99	REG_IGNORE_ONE(pad);
100	/* TBD: disallow updates to STATUS32 etc*/
101	REG_IN_CHUNK(scratch, pad2, ptregs);	/* pt_regs[bta..sp] */
102	REG_IGNORE_ONE(pad2);
103	REG_IN_CHUNK(callee, efa, cregs);	/* callee_regs[r25..r13] */
104	REG_IGNORE_ONE(efa);			/* efa update invalid */
105	REG_IGNORE_ONE(stop_pc);			/* PC updated via @ret */
106
107	return ret;
108}
109
110enum arc_getset {
111	REGSET_GENERAL,
112};
113
114static const struct user_regset arc_regsets[] = {
115	[REGSET_GENERAL] = {
116	       .core_note_type = NT_PRSTATUS,
117	       .n = ELF_NGREG,
118	       .size = sizeof(unsigned long),
119	       .align = sizeof(unsigned long),
120	       .get = genregs_get,
121	       .set = genregs_set,
122	}
123};
124
125static const struct user_regset_view user_arc_view = {
126	.name		= UTS_MACHINE,
127	.e_machine	= EM_ARCOMPACT,
128	.regsets	= arc_regsets,
129	.n		= ARRAY_SIZE(arc_regsets)
130};
131
132const struct user_regset_view *task_user_regset_view(struct task_struct *task)
133{
134	return &user_arc_view;
135}
136
137void ptrace_disable(struct task_struct *child)
138{
139}
140
141long arch_ptrace(struct task_struct *child, long request,
142		 unsigned long addr, unsigned long data)
143{
144	int ret = -EIO;
145
146	pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
147
148	switch (request) {
149	case PTRACE_GET_THREAD_AREA:
150		ret = put_user(task_thread_info(child)->thr_ptr,
151			       (unsigned long __user *)data);
152		break;
153	default:
154		ret = ptrace_request(child, request, addr, data);
155		break;
156	}
157
158	return ret;
159}
160
161asmlinkage int syscall_trace_entry(struct pt_regs *regs)
162{
163	if (tracehook_report_syscall_entry(regs))
164		return ULONG_MAX;
165
166	return regs->r8;
167}
168
169asmlinkage void syscall_trace_exit(struct pt_regs *regs)
170{
171	tracehook_report_syscall_exit(regs, 0);
172}
173