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