summaryrefslogtreecommitdiff
path: root/arch/hexagon/kernel/ptrace.c
blob: a5a89e944257c95f45899fe6dad803c094d3b114 (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
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Ptrace support for Hexagon
 *
 * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved.
 */

#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,
		   srtuct membuf to)
{
	struct pt_regs *regs = task_pt_regs(target);

	/* 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.
	 */
	membuf_write(&to, &regs->r00, 32*sizeof(unsigned long));
	/* Must be exactly same sequence as struct user_regs_struct */
	membuf_store(&to, regs->sa0);
	membuf_store(&to, regs->lc0);
	membuf_store(&to, regs->sa1);
	membuf_store(&to, regs->lc1);
	membuf_store(&to, regs->m0);
	membuf_store(&to, regs->m1);
	membuf_store(&to, regs->usr);
	membuf_store(&to, regs->p3_0);
	membuf_store(&to, regs->gp);
	membuf_store(&to, regs->ugp);
	membuf_store(&to, pt_elr(regs)); // pc
	membuf_store(&to, (unsigned long)pt_cause(regs)); // cause
	membuf_store(&to, pt_badva(regs)); // badva
#if CONFIG_HEXAGON_ARCH_VERSION >=4
	membuf_store(&to, regs->cs0);
	membuf_store(&to, regs->cs1);
	return membuf_zero(&to, sizeof(unsigned long));
#else
	return membuf_zero(&to, 3 * sizeof(unsigned long));
#endif
}

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),
		.regset_get = genregs_get,
		.set = genregs_set,
	},
};

static const struct user_regset_view hexagon_user_view = {
	.name = "hexagon",
	.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);
}