summaryrefslogtreecommitdiffstats
path: root/arch/hexagon/kernel/ptrace.c
blob: ecd75e2e8eb391a6598db7bb092cc5701f1545d6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
/*
 * Ptrace support for Hexagon
 *
 * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

#include <generated/compile.h>

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/sched/task_stack.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/regset.h>
#include <linux/user.h>
#include <linux/elf.h>

#include <asm/user.h>

#if arch_has_single_step()
/*  Both called from ptrace_resume  */
void user_enable_single_step(struct task_struct *child)
{
	pt_set_singlestep(task_pt_regs(child));
	set_tsk_thread_flag(child, TIF_SINGLESTEP);
}

void user_disable_single_step(struct task_struct *child)
{
	pt_clr_singlestep(task_pt_regs(child));
	clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}
#endif

static int genregs_get(struct task_struct *target,
		   const struct user_regset *regset,
		   unsigned int pos, unsigned int count,
		   void *kbuf, void __user *ubuf)
{
	int ret;
	unsigned int dummy;
	struct pt_regs *regs = task_pt_regs(target);


	if (!regs)
		return -EIO;

	/* The general idea here is that the copyout must happen in
	 * exactly the same order in which the userspace expects these
	 * regs. Now, the sequence in userspace does not match the
	 * sequence in the kernel, so everything past the 32 gprs
	 * happens one at a time.
	 */
	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
				  &regs->r00, 0, 32*sizeof(unsigned long));

#define ONEXT(KPT_REG, USR_REG) \
	if (!ret) \
		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, \
			KPT_REG, offsetof(struct user_regs_struct, USR_REG), \
			offsetof(struct user_regs_struct, USR_REG) + \
				 sizeof(unsigned long));

	/* Must be exactly same sequence as struct user_regs_struct */
	ONEXT(&regs->sa0, sa0);
	ONEXT(&regs->lc0, lc0);
	ONEXT(&regs->sa1, sa1);
	ONEXT(&regs->lc1, lc1);
	ONEXT(&regs->m0, m0);
	ONEXT(&regs->m1, m1);
	ONEXT(&regs->usr, usr);
	ONEXT(&regs->preds, p3_0);
	ONEXT(&regs->gp, gp);
	ONEXT(&regs->ugp, ugp);
	ONEXT(&pt_elr(regs), pc);
	dummy = pt_cause(regs);
	ONEXT(&dummy, cause);
	ONEXT(&pt_badva(regs), badva);
#if CONFIG_HEXAGON_ARCH_VERSION >=4
	ONEXT(&regs->cs0, cs0);
	ONEXT(&regs->cs1, cs1);
#endif

	/* Pad the rest with zeros, if needed */
	if (!ret)
		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
					offsetof(struct user_regs_struct, pad1), -1);
	return ret;
}

static int genregs_set(struct task_struct *target,
		   const struct user_regset *regset,
		   unsigned int pos, unsigned int count,
		   const void *kbuf, const void __user *ubuf)
{
	int ret;
	unsigned long bucket;
	struct pt_regs *regs = task_pt_regs(target);

	if (!regs)
		return -EIO;

	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
				 &regs->r00, 0, 32*sizeof(unsigned long));

#define INEXT(KPT_REG, USR_REG) \
	if (!ret) \
		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
			KPT_REG, offsetof(struct user_regs_struct, USR_REG), \
			offsetof(struct user_regs_struct, USR_REG) + \
				sizeof(unsigned long));

	/* Must be exactly same sequence as struct user_regs_struct */
	INEXT(&regs->sa0, sa0);
	INEXT(&regs->lc0, lc0);
	INEXT(&regs->sa1, sa1);
	INEXT(&regs->lc1, lc1);
	INEXT(&regs->m0, m0);
	INEXT(&regs->m1, m1);
	INEXT(&regs->usr, usr);
	INEXT(&regs->preds, p3_0);
	INEXT(&regs->gp, gp);
	INEXT(&regs->ugp, ugp);
	INEXT(&pt_elr(regs), pc);

	/* CAUSE and BADVA aren't writeable. */
	INEXT(&bucket, cause);
	INEXT(&bucket, badva);

#if CONFIG_HEXAGON_ARCH_VERSION >=4
	INEXT(&regs->cs0, cs0);
	INEXT(&regs->cs1, cs1);
#endif

	/* Ignore the rest, if needed */
	if (!ret)
		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
					offsetof(struct user_regs_struct, pad1), -1);

	if (ret)
		return ret;

	/*
	 * This is special; SP is actually restored by the VM via the
	 * special event record which is set by the special trap.
	 */
	regs->hvmer.vmpsp = regs->r29;
	return 0;
}

enum hexagon_regset {
	REGSET_GENERAL,
};

static const struct user_regset hexagon_regsets[] = {
	[REGSET_GENERAL] = {
		.core_note_type = NT_PRSTATUS,
		.n = ELF_NGREG,
		.size = sizeof(unsigned long),
		.align = sizeof(unsigned long),
		.get = genregs_get,
		.set = genregs_set,
	},
};

static const struct user_regset_view hexagon_user_view = {
	.name = UTS_MACHINE,
	.e_machine = ELF_ARCH,
	.ei_osabi = ELF_OSABI,
	.regsets = hexagon_regsets,
	.e_flags = ELF_CORE_EFLAGS,
	.n = ARRAY_SIZE(hexagon_regsets)
};

const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
	return &hexagon_user_view;
}

void ptrace_disable(struct task_struct *child)
{
	/* Boilerplate - resolves to null inline if no HW single-step */
	user_disable_single_step(child);
}

long arch_ptrace(struct task_struct *child, long request,
		 unsigned long addr, unsigned long data)
{
	return ptrace_request(child, request, addr, data);
}
OpenPOWER on IntegriCloud