arch/h8300/kernel/ptrace.c

   1 /*
   2  *  linux/arch/h8300/kernel/ptrace.c
   3  *
   4  *  Yoshinori Sato <ysato@users.sourceforge.jp>
   5  *
   6  *  Based on:
   7  *  linux/arch/m68k/kernel/ptrace.c
   8  *
   9  *  Copyright (C) 1994 by Hamish Macdonald
  10  *  Taken from linux/kernel/ptrace.c and modified for M680x0.
  11  *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
  12  *
  13  * This file is subject to the terms and conditions of the GNU General
  14  * Public License.  See the file COPYING in the main directory of
  15  * this archive for more details.
  16  */
  17
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/mm.h>
  21 #include <linux/smp.h>
  22 #include <linux/smp_lock.h>
  23 #include <linux/errno.h>
  24 #include <linux/ptrace.h>
  25 #include <linux/user.h>
  26 #include <linux/config.h>
  27 #include <linux/signal.h>
  28
  29 #include <asm/uaccess.h>
  30 #include <asm/page.h>
  31 #include <asm/pgtable.h>
  32 #include <asm/system.h>
  33 #include <asm/processor.h>
  34 #include <asm/signal.h>
  35
  36 /* cpu depend functions */
  37 extern long h8300_get_reg(struct task_struct *task, int regno);
  38 extern int  h8300_put_reg(struct task_struct *task, int regno, unsigned long data);
  39 extern void h8300_disable_trace(struct task_struct *child);
  40 extern void h8300_enable_trace(struct task_struct *child);
  41
  42 /*
  43  * does not yet catch signals sent when the child dies.
  44  * in exit.c or in signal.c.
  45  */
  46
  47 inline
  48 static int read_long(struct task_struct * tsk, unsigned long addr,
  49         unsigned long * result)
  50 {
  51         *result = *(unsigned long *)addr;
  52         return 0;
  53 }
  54
  55 void ptrace_disable(struct task_struct *child)
  56 {
  57         h8300_disable_trace(child);
  58 }
  59
  60 long arch_ptrace(struct task_struct *child, long request, long addr, long data)
  61 {
  62         int ret;
  63
  64         switch (request) {
  65                 case PTRACE_PEEKTEXT: /* read word at location addr. */
  66                 case PTRACE_PEEKDATA: {
  67                         unsigned long tmp;
  68
  69                         ret = read_long(child, addr, &tmp);
  70                         if (ret < 0)
  71                                 break ;
  72                         ret = put_user(tmp, (unsigned long *) data);
  73                         break ;
  74                 }
  75
  76         /* read the word at location addr in the USER area. */
  77                 case PTRACE_PEEKUSR: {
  78                         unsigned long tmp = 0;
  79
  80                         if ((addr & 3) || addr < 0 || addr >= sizeof(struct user)) {
  81                                 ret = -EIO;
  82                                 break ;
  83                         }
  84
  85                         ret = 0;  /* Default return condition */
  86                         addr = addr >> 2; /* temporary hack. */
  87
  88                         if (addr < H8300_REGS_NO)
  89                                 tmp = h8300_get_reg(child, addr);
  90                         else {
  91                                 switch(addr) {
  92                                 case 49:
  93                                         tmp = child->mm->start_code;
  94                                         break ;
  95                                 case 50:
  96                                         tmp = child->mm->start_data;
  97                                         break ;
  98                                 case 51:
  99                                         tmp = child->mm->end_code;
 100                                         break ;
 101                                 case 52:
 102                                         tmp = child->mm->end_data;
 103                                         break ;
 104                                 default:
 105                                         ret = -EIO;
 106                                 }
 107                         }
 108                         if (!ret)
 109                                 ret = put_user(tmp,(unsigned long *) data);
 110                         break ;
 111                 }
 112
 113       /* when I and D space are separate, this will have to be fixed. */
 114                 case PTRACE_POKETEXT: /* write the word at location addr. */
 115                 case PTRACE_POKEDATA:
 116                         ret = 0;
 117                         if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
 118                                 break;
 119                         ret = -EIO;
 120                         break;
 121
 122                 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 123                         if ((addr & 3) || addr < 0 || addr >= sizeof(struct user)) {
 124                                 ret = -EIO;
 125                                 break ;
 126                         }
 127                         addr = addr >> 2; /* temporary hack. */
 128
 129                         if (addr == PT_ORIG_ER0) {
 130                                 ret = -EIO;
 131                                 break ;
 132                         }
 133                         if (addr < H8300_REGS_NO) {
 134                                 ret = h8300_put_reg(child, addr, data);
 135                                 break ;
 136                         }
 137                         ret = -EIO;
 138                         break ;
 139                 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
 140                 case PTRACE_CONT: { /* restart after signal. */
 141                         ret = -EIO;
 142                         if (!valid_signal(data))
 143                                 break ;
 144                         if (request == PTRACE_SYSCALL)
 145                                 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 146                         else
 147                                 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 148                         child->exit_code = data;
 149                         wake_up_process(child);
 150                         /* make sure the single step bit is not set. */
 151                         h8300_disable_trace(child);
 152                         ret = 0;
 153                 }
 154
 155 /*
 156  * make the child exit.  Best I can do is send it a sigkill.
 157  * perhaps it should be put in the status that it wants to
 158  * exit.
 159  */
 160                 case PTRACE_KILL: {
 161
 162                         ret = 0;
 163                         if (child->exit_state == EXIT_ZOMBIE) /* already dead */
 164                                 break;
 165                         child->exit_code = SIGKILL;
 166                         h8300_disable_trace(child);
 167                         wake_up_process(child);
 168                         break;
 169                 }
 170
 171                 case PTRACE_SINGLESTEP: {  /* set the trap flag. */
 172                         ret = -EIO;
 173                         if (!valid_signal(data))
 174                                 break;
 175                         clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 176                         child->exit_code = data;
 177                         h8300_enable_trace(child);
 178                         wake_up_process(child);
 179                         ret = 0;
 180                         break;
 181                 }
 182
 183                 case PTRACE_DETACH:     /* detach a process that was attached. */
 184                         ret = ptrace_detach(child, data);
 185                         break;
 186
 187                 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
 188                         int i;
 189                         unsigned long tmp;
 190                         for (i = 0; i < H8300_REGS_NO; i++) {
 191                             tmp = h8300_get_reg(child, i);
 192                             if (put_user(tmp, (unsigned long *) data)) {
 193                                 ret = -EFAULT;
 194                                 break;
 195                             }
 196                             data += sizeof(long);
 197                         }
 198                         ret = 0;
 199                         break;
 200                 }
 201
 202                 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
 203                         int i;
 204                         unsigned long tmp;
 205                         for (i = 0; i < H8300_REGS_NO; i++) {
 206                             if (get_user(tmp, (unsigned long *) data)) {
 207                                 ret = -EFAULT;
 208                                 break;
 209                             }
 210                             h8300_put_reg(child, i, tmp);
 211                             data += sizeof(long);
 212                         }
 213                         ret = 0;
 214                         break;
 215                 }
 216
 217                 default:
 218                         ret = -EIO;
 219                         break;
 220         }
 221         return ret;
 222 }
 223
 224 asmlinkage void syscall_trace(void)
 225 {
 226         if (!test_thread_flag(TIF_SYSCALL_TRACE))
 227                 return;
 228         if (!(current->ptrace & PT_PTRACED))
 229                 return;
 230         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
 231                                  ? 0x80 : 0));
 232         /*
 233          * this isn't the same as continuing with a signal, but it will do
 234          * for normal use.  strace only continues with a signal if the
 235          * stopping signal is not SIGTRAP.  -brl
 236          */
 237         if (current->exit_code) {
 238                 send_sig(current->exit_code, current, 1);
 239                 current->exit_code = 0;
 240         }
 241 }