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