unsigned long addr, unsigned long data)
 {
        int ret;
+       int regno = addr >> 2;
+       unsigned long __user *datap = (unsigned long __user *) data;
 
        switch (request) {
                /* read the word at location addr in the USER area. */
                        unsigned long tmp;
                        
                        ret = -EIO;
-                       if ((addr & 3) || addr < 0 ||
-                           addr > sizeof(struct user) - 3)
+                       if ((addr & 3) || addr > sizeof(struct user) - 3)
                                break;
                        
                        tmp = 0;  /* Default return condition */
-                       addr = addr >> 2; /* temporary hack. */
                        ret = -EIO;
-                       if (addr < 19) {
-                               tmp = get_reg(child, addr);
-                               if (addr == PT_SR)
+                       if (regno < 19) {
+                               tmp = get_reg(child, regno);
+                               if (regno == PT_SR)
                                        tmp >>= 16;
-                       } else if (addr >= 21 && addr < 49) {
-                               tmp = child->thread.fp[addr - 21];
-                       } else if (addr == 49) {
+                       } else if (regno >= 21 && regno < 49) {
+                               tmp = child->thread.fp[regno - 21];
+                       } else if (regno == 49) {
                                tmp = child->mm->start_code;
-                       } else if (addr == 50) {
+                       } else if (regno == 50) {
                                tmp = child->mm->start_data;
-                       } else if (addr == 51) {
+                       } else if (regno == 51) {
                                tmp = child->mm->end_code;
                        } else
                                break;
-                       ret = put_user(tmp,(unsigned long *) data);
+                       ret = put_user(tmp, datap);
                        break;
                }
 
                case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
                        ret = -EIO;
-                       if ((addr & 3) || addr < 0 ||
-                           addr > sizeof(struct user) - 3)
+                       if ((addr & 3) || addr > sizeof(struct user) - 3)
                                break;
 
-                       addr = addr >> 2; /* temporary hack. */
-                           
-                       if (addr == PT_SR) {
+                       if (regno == PT_SR) {
                                data &= SR_MASK;
                                data <<= 16;
                                data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
                        }
-                       if (addr < 19) {
-                               if (put_reg(child, addr, data))
+                       if (regno < 19) {
+                               if (put_reg(child, regno, data))
                                        break;
                                ret = 0;
                                break;
                        }
-                       if (addr >= 21 && addr < 48)
+                       if (regno >= 21 && regno < 48)
                        {
-                               child->thread.fp[addr - 21] = data;
+                               child->thread.fp[regno - 21] = data;
                                ret = 0;
                        }
                        break;
                            tmp = get_reg(child, i);
                            if (i == PT_SR)
                                tmp >>= 16;
-                           if (put_user(tmp, (unsigned long *) data)) {
+                           if (put_user(tmp, datap)) {
                                ret = -EFAULT;
                                break;
                            }
-                           data += sizeof(unsigned long);
+                           datap++;
                        }
                        ret = 0;
                        break;
                        int i;
                        unsigned long tmp;
                        for (i = 0; i < 19; i++) {
-                           if (get_user(tmp, (unsigned long *) data)) {
+                           if (get_user(tmp, datap)) {
                                ret = -EFAULT;
                                break;
                            }
                                tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
                            }
                            put_reg(child, i, tmp);
-                           data += sizeof(unsigned long);
+                           datap++;
                        }
                        ret = 0;
                        break;
 #ifdef PTRACE_GETFPREGS
                case PTRACE_GETFPREGS: { /* Get the child FPU state. */
                        ret = 0;
-                       if (copy_to_user((void *)data, &child->thread.fp,
+                       if (copy_to_user(datap, &child->thread.fp,
                                         sizeof(struct user_m68kfp_struct)))
                                ret = -EFAULT;
                        break;
 #ifdef PTRACE_SETFPREGS
                case PTRACE_SETFPREGS: { /* Set the child FPU state. */
                        ret = 0;
-                       if (copy_from_user(&child->thread.fp, (void *)data,
+                       if (copy_from_user(&child->thread.fp, datap,
                                           sizeof(struct user_m68kfp_struct)))
                                ret = -EFAULT;
                        break;
 #endif
 
        case PTRACE_GET_THREAD_AREA:
-               ret = put_user(task_thread_info(child)->tp_value,
-                              (unsigned long __user *)data);
+               ret = put_user(task_thread_info(child)->tp_value, datap);
                break;
 
                default: