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
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
|
/*
* arch/sh/kernel/process.c
*
* This file handles the architecture-dependent parts of process handling..
*
* Copyright (C) 1995 Linus Torvalds
*
* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
* Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC
* Copyright (C) 2002 - 2008 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/elfcore.h>
#include <linux/kallsyms.h>
#include <linux/fs.h>
#include <linux/ftrace.h>
#include <linux/hw_breakpoint.h>
#include <linux/prefetch.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#include <asm/fpu.h>
#include <asm/syscalls.h>
#include <asm/switch_to.h>
void show_regs(struct pt_regs * regs)
{
printk("\n");
printk("Pid : %d, Comm: \t\t%s\n", task_pid_nr(current), current->comm);
printk("CPU : %d \t\t%s (%s %.*s)\n\n",
smp_processor_id(), print_tainted(), init_utsname()->release,
(int)strcspn(init_utsname()->version, " "),
init_utsname()->version);
print_symbol("PC is at %s\n", instruction_pointer(regs));
print_symbol("PR is at %s\n", regs->pr);
printk("PC : %08lx SP : %08lx SR : %08lx ",
regs->pc, regs->regs[15], regs->sr);
#ifdef CONFIG_MMU
printk("TEA : %08x\n", __raw_readl(MMU_TEA));
#else
printk("\n");
#endif
printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n",
regs->regs[0],regs->regs[1],
regs->regs[2],regs->regs[3]);
printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n",
regs->regs[4],regs->regs[5],
regs->regs[6],regs->regs[7]);
printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n",
regs->regs[8],regs->regs[9],
regs->regs[10],regs->regs[11]);
printk("R12 : %08lx R13 : %08lx R14 : %08lx\n",
regs->regs[12],regs->regs[13],
regs->regs[14]);
printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n",
regs->mach, regs->macl, regs->gbr, regs->pr);
show_trace(NULL, (unsigned long *)regs->regs[15], regs);
show_code(regs);
}
/*
* Create a kernel thread
*/
__noreturn void kernel_thread_helper(void *arg, int (*fn)(void *))
{
do_exit(fn(arg));
}
/* Don't use this in BL=1(cli). Or else, CPU resets! */
int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
{
struct pt_regs regs;
int pid;
memset(®s, 0, sizeof(regs));
regs.regs[4] = (unsigned long)arg;
regs.regs[5] = (unsigned long)fn;
regs.pc = (unsigned long)kernel_thread_helper;
regs.sr = SR_MD;
#if defined(CONFIG_SH_FPU)
regs.sr |= SR_FD;
#endif
/* Ok, create the new process.. */
pid = do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0,
®s, 0, NULL, NULL);
return pid;
}
EXPORT_SYMBOL(kernel_thread);
void start_thread(struct pt_regs *regs, unsigned long new_pc,
unsigned long new_sp)
{
regs->pr = 0;
regs->sr = SR_FD;
regs->pc = new_pc;
regs->regs[15] = new_sp;
free_thread_xstate(current);
}
EXPORT_SYMBOL(start_thread);
/*
* Free current thread data structures etc..
*/
void exit_thread(void)
{
}
void flush_thread(void)
{
struct task_struct *tsk = current;
flush_ptrace_hw_breakpoint(tsk);
#if defined(CONFIG_SH_FPU)
/* Forget lazy FPU state */
clear_fpu(tsk, task_pt_regs(tsk));
clear_used_math();
#endif
}
void release_thread(struct task_struct *dead_task)
{
/* do nothing */
}
/* Fill in the fpu structure for a core dump.. */
int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu)
{
int fpvalid = 0;
#if defined(CONFIG_SH_FPU)
struct task_struct *tsk = current;
fpvalid = !!tsk_used_math(tsk);
if (fpvalid)
fpvalid = !fpregs_get(tsk, NULL, 0,
sizeof(struct user_fpu_struct),
fpu, NULL);
#endif
return fpvalid;
}
EXPORT_SYMBOL(dump_fpu);
asmlinkage void ret_from_fork(void);
int copy_thread(unsigned long clone_flags, unsigned long usp,
unsigned long unused,
struct task_struct *p, struct pt_regs *regs)
{
struct thread_info *ti = task_thread_info(p);
struct pt_regs *childregs;
#if defined(CONFIG_SH_DSP)
struct task_struct *tsk = current;
if (is_dsp_enabled(tsk)) {
/* We can use the __save_dsp or just copy the struct:
* __save_dsp(p);
* p->thread.dsp_status.status |= SR_DSP
*/
p->thread.dsp_status = tsk->thread.dsp_status;
}
#endif
childregs = task_pt_regs(p);
*childregs = *regs;
if (user_mode(regs)) {
childregs->regs[15] = usp;
ti->addr_limit = USER_DS;
} else {
childregs->regs[15] = (unsigned long)childregs;
ti->addr_limit = KERNEL_DS;
ti->status &= ~TS_USEDFPU;
p->fpu_counter = 0;
}
if (clone_flags & CLONE_SETTLS)
childregs->gbr = childregs->regs[0];
childregs->regs[0] = 0; /* Set return value for child */
p->thread.sp = (unsigned long) childregs;
p->thread.pc = (unsigned long) ret_from_fork;
memset(p->thread.ptrace_bps, 0, sizeof(p->thread.ptrace_bps));
return 0;
}
/*
* switch_to(x,y) should switch tasks from x to y.
*
*/
__notrace_funcgraph struct task_struct *
__switch_to(struct task_struct *prev, struct task_struct *next)
{
struct thread_struct *next_t = &next->thread;
unlazy_fpu(prev, task_pt_regs(prev));
/* we're going to use this soon, after a few expensive things */
if (next->fpu_counter > 5)
prefetch(next_t->xstate);
#ifdef CONFIG_MMU
/*
* Restore the kernel mode register
* k7 (r7_bank1)
*/
asm volatile("ldc %0, r7_bank"
: /* no output */
: "r" (task_thread_info(next)));
#endif
/*
* If the task has used fpu the last 5 timeslices, just do a full
* restore of the math state immediately to avoid the trap; the
* chances of needing FPU soon are obviously high now
*/
if (next->fpu_counter > 5)
__fpu_state_restore();
return prev;
}
asmlinkage int sys_fork(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
#ifdef CONFIG_MMU
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL);
#else
/* fork almost works, enough to trick you into looking elsewhere :-( */
return -EINVAL;
#endif
}
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
unsigned long parent_tidptr,
unsigned long child_tidptr,
struct pt_regs __regs)
{
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
if (!newsp)
newsp = regs->regs[15];
return do_fork(clone_flags, newsp, regs, 0,
(int __user *)parent_tidptr,
(int __user *)child_tidptr);
}
/*
* This is trivial, and on the face of it looks like it
* could equally well be done in user mode.
*
* Not so, for quite unobvious reasons - register pressure.
* In user mode vfork() cannot have a stack frame, and if
* done by calling the "clone()" system call directly, you
* do not have enough call-clobbered registers to hold all
* the information you need.
*/
asmlinkage int sys_vfork(unsigned long r4, unsigned long r5,
unsigned long r6, unsigned long r7,
struct pt_regs __regs)
{
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs,
0, NULL, NULL);
}
/*
* sys_execve() executes a new program.
*/
asmlinkage int sys_execve(const char __user *ufilename,
const char __user *const __user *uargv,
const char __user *const
|