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 = generic_ptrace_pokedata(child, addr, data);
 115                         break;
 116
 117                 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
 118                         if ((addr & 3) || addr < 0 || addr >= sizeof(struct user)) {
 119                                 ret = -EIO;
 120                                 break ;
 121                         }
 122                         addr = addr >> 2; /* temporary hack. */
 123
 124                         if (addr == PT_ORIG_ER0) {
 125                                 ret = -EIO;
 126                                 break ;
 127                         }
 128                         if (addr < H8300_REGS_NO) {
 129                                 ret = h8300_put_reg(child, addr, data);
 130                                 break ;
 131                         }
 132                         ret = -EIO;
 133                         break ;
 134                 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
 135                 case PTRACE_CONT: { /* restart after signal. */
 136                         ret = -EIO;
 137                         if (!valid_signal(data))
 138                                 break ;
 139                         if (request == PTRACE_SYSCALL)
 140                                 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 141                         else
 142                                 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 143                         child->exit_code = data;
 144                         wake_up_process(child);
 145                         /* make sure the single step bit is not set. */
 146                         h8300_disable_trace(child);
 147                         ret = 0;
 148                 }
 149
 150 /*
 151  * make the child exit.  Best I can do is send it a sigkill.
 152  * perhaps it should be put in the status that it wants to
 153  * exit.
 154  */
 155                 case PTRACE_KILL: {
 156
 157                         ret = 0;
 158                         if (child->exit_state == EXIT_ZOMBIE) /* already dead */
 159                                 break;
 160                         child->exit_code = SIGKILL;
 161                         h8300_disable_trace(child);
 162                         wake_up_process(child);
 163                         break;
 164                 }
 165
 166                 case PTRACE_SINGLESTEP: {  /* set the trap flag. */
 167                         ret = -EIO;
 168                         if (!valid_signal(data))
 169                                 break;
 170                         clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
 171                         child->exit_code = data;
 172                         h8300_enable_trace(child);
 173                         wake_up_process(child);
 174                         ret = 0;
 175                         break;
 176                 }
 177
 178                 case PTRACE_DETACH:     /* detach a process that was attached. */
 179                         ret = ptrace_detach(child, data);
 180                         break;
 181
 182                 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
 183                         int i;
 184                         unsigned long tmp;
 185                         for (i = 0; i < H8300_REGS_NO; i++) {
 186                             tmp = h8300_get_reg(child, i);
 187                             if (put_user(tmp, (unsigned long *) data)) {
 188                                 ret = -EFAULT;
 189                                 break;
 190                             }
 191                             data += sizeof(long);
 192                         }
 193                         ret = 0;
 194                         break;
 195                 }
 196
 197                 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
 198                         int i;
 199                         unsigned long tmp;
 200                         for (i = 0; i < H8300_REGS_NO; i++) {
 201                             if (get_user(tmp, (unsigned long *) data)) {
 202                                 ret = -EFAULT;
 203                                 break;
 204                             }
 205                             h8300_put_reg(child, i, tmp);
 206                             data += sizeof(long);
 207                         }
 208                         ret = 0;
 209                         break;
 210                 }
 211
 212                 default:
 213                         ret = -EIO;
 214                         break;
 215         }
 216         return ret;
 217 }
 218
 219 asmlinkage void do_syscall_trace(void)
 220 {
 221         if (!test_thread_flag(TIF_SYSCALL_TRACE))
 222                 return;
 223         if (!(current->ptrace & PT_PTRACED))
 224                 return;
 225         ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
 226                                  ? 0x80 : 0));
 227         /*
 228          * this isn't the same as continuing with a signal, but it will do
 229          * for normal use.  strace only continues with a signal if the
 230          * stopping signal is not SIGTRAP.  -brl
 231          */
 232         if (current->exit_code) {
 233                 send_sig(current->exit_code, current, 1);
 234                 current->exit_code = 0;
 235         }
 236 }