2 * linux/arch/m68k/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
]);
90 asmlinkage
int sys_ptrace(long request
, long pid
, long addr
, long data
)
92 struct task_struct
*child
;
98 if (request
== PTRACE_TRACEME
) {
99 /* are we already being traced? */
100 if (current
->ptrace
& PT_PTRACED
)
102 /* set the ptrace bit in the process flags. */
103 current
->ptrace
|= PT_PTRACED
;
108 read_lock(&tasklist_lock
);
109 child
= find_task_by_pid(pid
);
110 read_unlock(&tasklist_lock
); /* FIXME!!! */
114 if (pid
== 1) /* you may not mess with init */
116 if (request
== PTRACE_ATTACH
) {
117 if (child
== current
)
119 if ((!child
->dumpable
||
120 (current
->uid
!= child
->euid
) ||
121 (current
->uid
!= child
->suid
) ||
122 (current
->uid
!= child
->uid
) ||
123 (current
->gid
!= child
->egid
) ||
124 (current
->gid
!= child
->sgid
) ||
125 (!cap_issubset(child
->cap_permitted
, current
->cap_permitted
)) ||
126 (current
->gid
!= child
->gid
)) && !capable(CAP_SYS_PTRACE
))
128 /* the same process cannot be attached many times */
129 if (child
->ptrace
& PT_PTRACED
)
131 child
->ptrace
|= PT_PTRACED
;
133 write_lock_irqsave(&tasklist_lock
, flags
);
134 if (child
->p_pptr
!= current
) {
136 child
->p_pptr
= current
;
139 write_unlock_irqrestore(&tasklist_lock
, flags
);
141 send_sig(SIGSTOP
, child
, 1);
146 if (!(child
->ptrace
& PT_PTRACED
))
148 if (child
->state
!= TASK_STOPPED
) {
149 if (request
!= PTRACE_KILL
)
152 if (child
->p_pptr
!= current
)
156 /* when I and D space are separate, these will need to be fixed. */
157 case PTRACE_PEEKTEXT
: /* read word at location addr. */
158 case PTRACE_PEEKDATA
: {
162 copied
= access_process_vm(child
, addr
, &tmp
, sizeof(tmp
), 0);
164 if (copied
!= sizeof(tmp
))
166 ret
= put_user(tmp
,(unsigned long *) data
);
170 /* read the word at location addr in the USER area. */
171 case PTRACE_PEEKUSR
: {
175 if ((addr
& 3) || addr
< 0 || addr
>= sizeof(struct user
))
178 tmp
= 0; /* Default return condition */
179 addr
= addr
>> 2; /* temporary hack. */
182 tmp
= get_reg(child
, addr
);
185 } else if (addr
>= 21 && addr
< 49) {
186 tmp
= child
->thread
.fp
[addr
- 21];
187 #ifdef CONFIG_M68KFPU_EMU
188 /* Convert internal fpu reg representation
189 * into long double format
191 if (FPU_IS_EMU
&& (addr
< 45) && !(addr
% 3))
192 tmp
= ((tmp
& 0xffff0000) << 15) |
193 ((tmp
& 0x0000ffff) << 16);
197 ret
= put_user(tmp
,(unsigned long *) data
);
201 /* when I and D space are separate, this will have to be fixed. */
202 case PTRACE_POKETEXT
: /* write the word at location addr. */
203 case PTRACE_POKEDATA
:
205 if (access_process_vm(child
, addr
, &data
, sizeof(data
), 1) == sizeof(data
))
210 case PTRACE_POKEUSR
: /* write the word at location addr in the USER area */
212 if ((addr
& 3) || addr
< 0 || addr
>= sizeof(struct user
))
215 addr
= addr
>> 2; /* temporary hack. */
220 data
|= get_reg(child
, PT_SR
) & ~(SR_MASK
<< 16);
223 if (put_reg(child
, addr
, data
))
228 if (addr
>= 21 && addr
< 48)
230 #ifdef CONFIG_M68KFPU_EMU
231 /* Convert long double format
232 * into internal fpu reg representation
234 if (FPU_IS_EMU
&& (addr
< 45) && !(addr
% 3)) {
235 data
= (unsigned long)data
<< 15;
236 data
= (data
& 0xffff0000) |
237 ((data
& 0x0000ffff) >> 1);
240 child
->thread
.fp
[addr
- 21] = data
;
245 case PTRACE_SYSCALL
: /* continue and stop at next (return from) syscall */
246 case PTRACE_CONT
: { /* restart after signal. */
250 if ((unsigned long) data
> _NSIG
)
252 if (request
== PTRACE_SYSCALL
)
253 child
->ptrace
|= PT_TRACESYS
;
255 child
->ptrace
&= ~PT_TRACESYS
;
256 child
->exit_code
= data
;
257 /* make sure the single step bit is not set. */
258 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
259 put_reg(child
, PT_SR
, tmp
);
260 wake_up_process(child
);
266 * make the child exit. Best I can do is send it a sigkill.
267 * perhaps it should be put in the status that it wants to
274 if (child
->state
== TASK_ZOMBIE
) /* already dead */
276 child
->exit_code
= SIGKILL
;
277 /* make sure the single step bit is not set. */
278 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
279 put_reg(child
, PT_SR
, tmp
);
280 wake_up_process(child
);
284 case PTRACE_SINGLESTEP
: { /* set the trap flag. */
288 if ((unsigned long) data
> _NSIG
)
290 child
->ptrace
&= ~PT_TRACESYS
;
291 tmp
= get_reg(child
, PT_SR
) | (TRACE_BITS
<< 16);
292 put_reg(child
, PT_SR
, tmp
);
294 child
->exit_code
= data
;
295 /* give it a chance to run. */
296 wake_up_process(child
);
301 case PTRACE_DETACH
: { /* detach a process that was attached. */
305 if ((unsigned long) data
> _NSIG
)
307 child
->ptrace
&= ~(PT_PTRACED
|PT_TRACESYS
);
308 child
->exit_code
= data
;
309 write_lock_irqsave(&tasklist_lock
, flags
);
311 child
->p_pptr
= child
->p_opptr
;
313 write_unlock_irqrestore(&tasklist_lock
, flags
);
314 /* make sure the single step bit is not set. */
315 tmp
= get_reg(child
, PT_SR
) & ~(TRACE_BITS
<< 16);
316 put_reg(child
, PT_SR
, tmp
);
317 wake_up_process(child
);
322 case PTRACE_GETREGS
: { /* Get all gp regs from the child. */
325 for (i
= 0; i
< 19; i
++) {
326 tmp
= get_reg(child
, i
);
329 if (put_user(tmp
, (unsigned long *) data
)) {
333 data
+= sizeof(long);
339 case PTRACE_SETREGS
: { /* Set all gp regs in the child. */
342 for (i
= 0; i
< 19; i
++) {
343 if (get_user(tmp
, (unsigned long *) data
)) {
350 tmp
|= get_reg(child
, PT_SR
) & ~(SR_MASK
<< 16);
352 put_reg(child
, i
, tmp
);
353 data
+= sizeof(long);
359 case PTRACE_GETFPREGS
: { /* Get the child FPU state. */
361 if (copy_to_user((void *)data
, &child
->thread
.fp
,
362 sizeof(struct user_m68kfp_struct
)))
367 case PTRACE_SETFPREGS
: { /* Set the child FPU state. */
369 if (copy_from_user(&child
->thread
.fp
, (void *)data
,
370 sizeof(struct user_m68kfp_struct
)))
384 asmlinkage
void syscall_trace(void)
387 if ((current
->ptrace
& (PT_PTRACED
|PT_TRACESYS
))
388 != (PT_PTRACED
|PT_TRACESYS
))
390 current
->exit_code
= SIGTRAP
;
391 current
->state
= TASK_STOPPED
;
392 notify_parent(current
, SIGCHLD
);
395 * this isn't the same as continuing with a signal, but it will do
396 * for normal use. strace only continues with a signal if the
397 * stopping signal is not SIGTRAP. -brl
399 if (current
->exit_code
) {
400 send_sig(current
->exit_code
, current
, 1);
401 current
->exit_code
= 0;