1/*
  2 * Copyright (C) 2014 Altera Corporation
  3 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
  4 *
  5 * This file is subject to the terms and conditions of the GNU General
  6 * Public License.  See the file COPYING in the main directory of this
  7 * archive for more details.
  8 */
  9
 10#include <linux/elf.h>
 11#include <linux/errno.h>
 12#include <linux/kernel.h>
 13#include <linux/mm.h>
 14#include <linux/ptrace.h>
 15#include <linux/regset.h>
 16#include <linux/sched.h>
 17#include <linux/tracehook.h>
 18#include <linux/uaccess.h>
 19#include <linux/user.h>
 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 *regs = task_pt_regs(target);
 27	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
 28	int ret = 0;
 29
 30#define REG_O_ZERO_RANGE(START, END)		\
 31	if (!ret)					\
 32		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
 33			START * 4, (END * 4) + 4);
 34
 35#define REG_O_ONE(PTR, LOC)	\
 36	if (!ret)			\
 37		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
 38			LOC * 4, (LOC * 4) + 4);
 39
 40#define REG_O_RANGE(PTR, START, END)	\
 41	if (!ret)				\
 42		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
 43			START * 4, (END * 4) + 4);
 44
 45	REG_O_ZERO_RANGE(PTR_R0, PTR_R0);
 46	REG_O_RANGE(&regs->r1, PTR_R1, PTR_R7);
 47	REG_O_RANGE(&regs->r8, PTR_R8, PTR_R15);
 48	REG_O_RANGE(sw, PTR_R16, PTR_R23);
 49	REG_O_ZERO_RANGE(PTR_R24, PTR_R25); /* et and bt */
 50	REG_O_ONE(&regs->gp, PTR_GP);
 51	REG_O_ONE(&regs->sp, PTR_SP);
 52	REG_O_ONE(&regs->fp, PTR_FP);
 53	REG_O_ONE(&regs->ea, PTR_EA);
 54	REG_O_ZERO_RANGE(PTR_BA, PTR_BA);
 55	REG_O_ONE(&regs->ra, PTR_RA);
 56	REG_O_ONE(&regs->ea, PTR_PC); /* use ea for PC */
 57	if (!ret)
 58		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
 59					 PTR_STATUS * 4, -1);
 60
 61	return ret;
 62}
 63
 64/*
 65 * Set the thread state from a regset passed in via ptrace
 66 */
 67static int genregs_set(struct task_struct *target,
 68		       const struct user_regset *regset,
 69		       unsigned int pos, unsigned int count,
 70		       const void *kbuf, const void __user *ubuf)
 71{
 72	struct pt_regs *regs = task_pt_regs(target);
 73	const struct switch_stack *sw = (struct switch_stack *)regs - 1;
 74	int ret = 0;
 75
 76#define REG_IGNORE_RANGE(START, END)		\
 77	if (!ret)					\
 78		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
 79			START * 4, (END * 4) + 4);
 80
 81#define REG_IN_ONE(PTR, LOC)	\
 82	if (!ret)			\
 83		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
 84			(void *)(PTR), LOC * 4, (LOC * 4) + 4);
 85
 86#define REG_IN_RANGE(PTR, START, END)	\
 87	if (!ret)				\
 88		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
 89			(void *)(PTR), START * 4, (END * 4) + 4);
 90
 91	REG_IGNORE_RANGE(PTR_R0, PTR_R0);
 92	REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
 93	REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
 94	REG_IN_RANGE(sw, PTR_R16, PTR_R23);
 95	REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
 96	REG_IN_ONE(&regs->gp, PTR_GP);
 97	REG_IN_ONE(&regs->sp, PTR_SP);
 98	REG_IN_ONE(&regs->fp, PTR_FP);
 99	REG_IN_ONE(&regs->ea, PTR_EA);
100	REG_IGNORE_RANGE(PTR_BA, PTR_BA);
101	REG_IN_ONE(&regs->ra, PTR_RA);
102	REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
103	if (!ret)
104		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
105					 PTR_STATUS * 4, -1);
106
107	return ret;
108}
109
110/*
111 * Define the register sets available on Nios2 under Linux
112 */
113enum nios2_regset {
114	REGSET_GENERAL,
115};
116
117static const struct user_regset nios2_regsets[] = {
118	[REGSET_GENERAL] = {
119		.core_note_type = NT_PRSTATUS,
120		.n = NUM_PTRACE_REG,
121		.size = sizeof(unsigned long),
122		.align = sizeof(unsigned long),
123		.get = genregs_get,
124		.set = genregs_set,
125	}
126};
127
128static const struct user_regset_view nios2_user_view = {
129	.name = "nios2",
130	.e_machine = ELF_ARCH,
131	.ei_osabi = ELF_OSABI,
132	.regsets = nios2_regsets,
133	.n = ARRAY_SIZE(nios2_regsets)
134};
135
136const struct user_regset_view *task_user_regset_view(struct task_struct *task)
137{
138	return &nios2_user_view;
139}
140
141void ptrace_disable(struct task_struct *child)
142{
143
144}
145
146long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
147		 unsigned long data)
148{
149	return ptrace_request(child, request, addr, data);
150}
151
152asmlinkage int do_syscall_trace_enter(void)
153{
154	int ret = 0;
155
156	if (test_thread_flag(TIF_SYSCALL_TRACE))
157		ret = tracehook_report_syscall_entry(task_pt_regs(current));
158
159	return ret;
160}
161
162asmlinkage void do_syscall_trace_exit(void)
163{
164	if (test_thread_flag(TIF_SYSCALL_TRACE))
165		tracehook_report_syscall_exit(task_pt_regs(current), 0);
166}