2 * linux/arch/m68knommu/kernel/ptrace.c
4 * Copyright (C) 1994 by Hamish Macdonald
5 * Taken from linux/kernel/ptrace.c and modified for M680x0.
6 * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
8 * This file is subject to the terms and conditions of the GNU General
9 * Public License. See the file COPYING in the main directory of
10 * this archive for more details.
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
16 #include <linux/smp.h>
17 #include <linux/smp_lock.h>
18 #include <linux/errno.h>
19 #include <linux/ptrace.h>
20 #include <linux/user.h>
21 #include <linux/config.h>
23 #include <asm/uaccess.h>
25 #include <asm/pgtable.h>
26 #include <asm/system.h>
27 #include <asm/processor.h>
30 * does not yet catch signals sent when the child dies.
31 * in exit.c or in signal.c.
34 /* determines which bits in the SR the user has access to. */
35 /* 1 = access 0 = no access */
36 #define SR_MASK 0x001f
38 /* sets the trace bits. */
39 #define TRACE_BITS 0x8000
41 /* Find the stack offset for a register, relative to thread.esp0. */
42 #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
43 #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
44 - sizeof(struct switch_stack))
45 /* Mapping from PT_xxx to the stack offset at which the register is
46 saved. Notice that usp has no stack-slot and needs to be treated
47 specially (see get_reg/put_reg below). */
48 static int regoff
[] = {
49 PT_REG(d1
), PT_REG(d2
), PT_REG(d3
), PT_REG(d4
),
50 PT_REG(d5
), SW_REG(d6
), SW_REG(d7
), PT_REG(a0
),
51 PT_REG(a1
), PT_REG(a2
), SW_REG(a3
), SW_REG(a4
),
52 SW_REG(a5
), SW_REG(a6
), PT_REG(d0
), -1,
53 PT_REG(orig_d0
), PT_REG(sr
), PT_REG(pc
),
57 * Get contents of register REGNO in task TASK.
59 static inline long get_reg(struct task_struct
*task
, int regno
)
64 addr
= &task
->thread
.usp
;
65 else if (regno
< sizeof(regoff
)/sizeof(regoff
[0]))
66 addr
= (unsigned long *)(task
->thread
.esp0
+ regoff
[regno
]);
73 * Write contents of register REGNO in task TASK.
75 static inline int put_reg(struct task_struct
*task
, int regno
,
81 addr
= &task
->thread
.usp
;
82 else if (regno
< sizeof(regoff
)/sizeof(regoff
[0]))
83 addr
= (unsigned long *) (task
->thread
.esp0
+ regoff
[regno
]);
91 * Called by kernel/ptrace.c when detaching..
93 * Make sure the single step bit is not set.
95 void ptrace_disable(struct task_struct
*child
)
98 /* make sure the single step bit is not set. */
99 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
100 put_reg(child
, PT_SR
, tmp
);
103 asmlinkage
int sys_ptrace(long request
, long pid
, long addr
, long data
)
105 struct task_struct
*child
;
110 if (request
== PTRACE_TRACEME
) {
111 /* are we already being traced? */
112 if (current
->ptrace
& PT_PTRACED
)
114 /* set the ptrace bit in the process flags. */
115 current
->ptrace
|= PT_PTRACED
;
120 read_lock(&tasklist_lock
);
121 child
= find_task_by_pid(pid
);
123 get_task_struct(child
);
124 read_unlock(&tasklist_lock
);
129 if (pid
== 1) /* you may not mess with init */
132 if (request
== PTRACE_ATTACH
) {
133 ret
= ptrace_attach(child
);
136 ret
= ptrace_check_attach(child
, request
== PTRACE_KILL
);
141 /* when I and D space are separate, these will need to be fixed. */
142 case PTRACE_PEEKTEXT
: /* read word at location addr. */
143 case PTRACE_PEEKDATA
: {
147 copied
= access_process_vm(child
, addr
, &tmp
, sizeof(tmp
), 0);
149 if (copied
!= sizeof(tmp
))
151 ret
= put_user(tmp
,(unsigned long *) data
);
155 /* read the word at location addr in the USER area. */
156 case PTRACE_PEEKUSR
: {
160 if ((addr
& 3) || addr
< 0 ||
161 addr
> sizeof(struct user
) - 3)
164 tmp
= 0; /* Default return condition */
165 addr
= addr
>> 2; /* temporary hack. */
168 tmp
= get_reg(child
, addr
);
171 } else if (addr
>= 21 && addr
< 49) {
172 tmp
= child
->thread
.fp
[addr
- 21];
173 #ifdef CONFIG_M68KFPU_EMU
174 /* Convert internal fpu reg representation
175 * into long double format
177 if (FPU_IS_EMU
&& (addr
< 45) && !(addr
% 3))
178 tmp
= ((tmp
& 0xffff0000) << 15) |
179 ((tmp
& 0x0000ffff) << 16);
181 } else if (addr
== 49) {
182 tmp
= child
->mm
->start_code
;
183 } else if (addr
== 50) {
184 tmp
= child
->mm
->start_data
;
185 } else if (addr
== 51) {
186 tmp
= child
->mm
->end_code
;
189 ret
= put_user(tmp
,(unsigned long *) data
);
193 /* when I and D space are separate, this will have to be fixed. */
194 case PTRACE_POKETEXT
: /* write the word at location addr. */
195 case PTRACE_POKEDATA
:
197 if (access_process_vm(child
, addr
, &data
, sizeof(data
), 1) == sizeof(data
))
202 case PTRACE_POKEUSR
: /* write the word at location addr in the USER area */
204 if ((addr
& 3) || addr
< 0 ||
205 addr
> sizeof(struct user
) - 3)
208 addr
= addr
>> 2; /* temporary hack. */
213 data
|= get_reg(child
, PT_SR
) & ~(SR_MASK
<< 16);
216 if (put_reg(child
, addr
, data
))
221 if (addr
>= 21 && addr
< 48)
223 #ifdef CONFIG_M68KFPU_EMU
224 /* Convert long double format
225 * into internal fpu reg representation
227 if (FPU_IS_EMU
&& (addr
< 45) && !(addr
% 3)) {
228 data
= (unsigned long)data
<< 15;
229 data
= (data
& 0xffff0000) |
230 ((data
& 0x0000ffff) >> 1);
233 child
->thread
.fp
[addr
- 21] = data
;
238 case PTRACE_SYSCALL
: /* continue and stop at next (return from) syscall */
239 case PTRACE_CONT
: { /* restart after signal. */
243 if ((unsigned long) data
> _NSIG
)
245 if (request
== PTRACE_SYSCALL
)
246 set_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
248 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
249 child
->exit_code
= data
;
250 /* make sure the single step bit is not set. */
251 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
252 put_reg(child
, PT_SR
, tmp
);
253 wake_up_process(child
);
259 * make the child exit. Best I can do is send it a sigkill.
260 * perhaps it should be put in the status that it wants to
267 if (child
->state
== TASK_ZOMBIE
) /* already dead */
269 child
->exit_code
= SIGKILL
;
270 /* make sure the single step bit is not set. */
271 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
272 put_reg(child
, PT_SR
, tmp
);
273 wake_up_process(child
);
277 case PTRACE_SINGLESTEP
: { /* set the trap flag. */
281 if ((unsigned long) data
> _NSIG
)
283 clear_tsk_thread_flag(child
, TIF_SYSCALL_TRACE
);
284 tmp
= get_reg(child
, PT_SR
) | (TRACE_BITS
<< 16);
285 put_reg(child
, PT_SR
, tmp
);
287 child
->exit_code
= data
;
288 /* give it a chance to run. */
289 wake_up_process(child
);
294 case PTRACE_DETACH
: /* detach a process that was attached. */
295 ret
= ptrace_detach(child
, data
);
298 case PTRACE_GETREGS
: { /* Get all gp regs from the child. */
301 for (i
= 0; i
< 19; i
++) {
302 tmp
= get_reg(child
, i
);
305 if (put_user(tmp
, (unsigned long *) data
)) {
309 data
+= sizeof(long);
315 case PTRACE_SETREGS
: { /* Set all gp regs in the child. */
318 for (i
= 0; i
< 19; i
++) {
319 if (get_user(tmp
, (unsigned long *) data
)) {
326 tmp
|= get_reg(child
, PT_SR
) & ~(SR_MASK
<< 16);
328 put_reg(child
, i
, tmp
);
329 data
+= sizeof(long);
335 #ifdef PTRACE_GETFPREGS
336 case PTRACE_GETFPREGS
: { /* Get the child FPU state. */
338 if (copy_to_user((void *)data
, &child
->thread
.fp
,
339 sizeof(struct user_m68kfp_struct
)))
345 #ifdef PTRACE_SETFPREGS
346 case PTRACE_SETFPREGS
: { /* Set the child FPU state. */
348 if (copy_from_user(&child
->thread
.fp
, (void *)data
,
349 sizeof(struct user_m68kfp_struct
)))
360 put_task_struct(child
);
366 asmlinkage
void syscall_trace(void)
368 if (!test_thread_flag(TIF_SYSCALL_TRACE
))
370 if (!(current
->ptrace
& PT_PTRACED
))
372 ptrace_notify(SIGTRAP
| ((current
->ptrace
& PT_TRACESYSGOOD
)
375 * this isn't the same as continuing with a signal, but it will do
376 * for normal use. strace only continues with a signal if the
377 * stopping signal is not SIGTRAP. -brl
379 if (current
->exit_code
) {
380 send_sig(current
->exit_code
, current
, 1);
381 current
->exit_code
= 0;