drivers/s390/net/fsm.c

   1 /**
   2  * $Id: fsm.c,v 1.6 2003/10/15 11:37:29 mschwide Exp $
   3  *
   4  * A generic FSM based on fsm used in isdn4linux
   5  *
   6  */
   7
   8 #include "fsm.h"
   9 #include <linux/config.h>
  10 #include <linux/module.h>
  11 #include <linux/timer.h>
  12
  13 MODULE_AUTHOR("(C) 2000 IBM Corp. by Fritz Elfert (felfert@millenux.com)");
  14 MODULE_DESCRIPTION("Finite state machine helper functions");
  15 MODULE_LICENSE("GPL");
  16
  17 fsm_instance *
  18 init_fsm(char *name, const char **state_names, const char **event_names, int nr_states,
  19                 int nr_events, const fsm_node *tmpl, int tmpl_len, gfp_t order)
  20 {
  21         int i;
  22         fsm_instance *this;
  23         fsm_function_t *m;
  24         fsm *f;
  25
  26         this = (fsm_instance *)kmalloc(sizeof(fsm_instance), order);
  27         if (this == NULL) {
  28                 printk(KERN_WARNING
  29                         "fsm(%s): init_fsm: Couldn't alloc instance\n", name);
  30                 return NULL;
  31         }
  32         memset(this, 0, sizeof(fsm_instance));
  33         strlcpy(this->name, name, sizeof(this->name));
  34
  35         f = (fsm *)kmalloc(sizeof(fsm), order);
  36         if (f == NULL) {
  37                 printk(KERN_WARNING
  38                         "fsm(%s): init_fsm: Couldn't alloc fsm\n", name);
  39                 kfree_fsm(this);
  40                 return NULL;
  41         }
  42         memset(f, 0, sizeof(fsm));
  43         f->nr_events = nr_events;
  44         f->nr_states = nr_states;
  45         f->event_names = event_names;
  46         f->state_names = state_names;
  47         this->f = f;
  48
  49         m = (fsm_function_t *)kmalloc(
  50                         sizeof(fsm_function_t) * nr_states * nr_events, order);
  51         if (m == NULL) {
  52                 printk(KERN_WARNING
  53                         "fsm(%s): init_fsm: Couldn't alloc jumptable\n", name);
  54                 kfree_fsm(this);
  55                 return NULL;
  56         }
  57         memset(m, 0, sizeof(fsm_function_t) * f->nr_states * f->nr_events);
  58         f->jumpmatrix = m;
  59
  60         for (i = 0; i < tmpl_len; i++) {
  61                 if ((tmpl[i].cond_state >= nr_states) ||
  62                     (tmpl[i].cond_event >= nr_events)   ) {
  63                         printk(KERN_ERR
  64                                 "fsm(%s): init_fsm: Bad template l=%d st(%ld/%ld) ev(%ld/%ld)\n",
  65                                 name, i, (long)tmpl[i].cond_state, (long)f->nr_states,
  66                                 (long)tmpl[i].cond_event, (long)f->nr_events);
  67                         kfree_fsm(this);
  68                         return NULL;
  69                 } else
  70                         m[nr_states * tmpl[i].cond_event + tmpl[i].cond_state] =
  71                                 tmpl[i].function;
  72         }
  73         return this;
  74 }
  75
  76 void
  77 kfree_fsm(fsm_instance *this)
  78 {
  79         if (this) {
  80                 if (this->f) {
  81                         kfree(this->f->jumpmatrix);
  82                         kfree(this->f);
  83                 }
  84                 kfree(this);
  85         } else
  86                 printk(KERN_WARNING
  87                         "fsm: kfree_fsm called with NULL argument\n");
  88 }
  89
  90 #if FSM_DEBUG_HISTORY
  91 void
  92 fsm_print_history(fsm_instance *fi)
  93 {
  94         int idx = 0;
  95         int i;
  96
  97         if (fi->history_size >= FSM_HISTORY_SIZE)
  98                 idx = fi->history_index;
  99
 100         printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
 101         for (i = 0; i < fi->history_size; i++) {
 102                 int e = fi->history[idx].event;
 103                 int s = fi->history[idx++].state;
 104                 idx %= FSM_HISTORY_SIZE;
 105                 if (e == -1)
 106                         printk(KERN_DEBUG "  S=%s\n",
 107                                fi->f->state_names[s]);
 108                 else
 109                         printk(KERN_DEBUG "  S=%s E=%s\n",
 110                                fi->f->state_names[s],
 111                                fi->f->event_names[e]);
 112         }
 113         fi->history_size = fi->history_index = 0;
 114 }
 115
 116 void
 117 fsm_record_history(fsm_instance *fi, int state, int event)
 118 {
 119         fi->history[fi->history_index].state = state;
 120         fi->history[fi->history_index++].event = event;
 121         fi->history_index %= FSM_HISTORY_SIZE;
 122         if (fi->history_size < FSM_HISTORY_SIZE)
 123                 fi->history_size++;
 124 }
 125 #endif
 126
 127 const char *
 128 fsm_getstate_str(fsm_instance *fi)
 129 {
 130         int st = atomic_read(&fi->state);
 131         if (st >= fi->f->nr_states)
 132                 return "Invalid";
 133         return fi->f->state_names[st];
 134 }
 135
 136 static void
 137 fsm_expire_timer(fsm_timer *this)
 138 {
 139 #if FSM_TIMER_DEBUG
 140         printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
 141                this->fi->name, this);
 142 #endif
 143         fsm_event(this->fi, this->expire_event, this->event_arg);
 144 }
 145
 146 void
 147 fsm_settimer(fsm_instance *fi, fsm_timer *this)
 148 {
 149         this->fi = fi;
 150         this->tl.function = (void *)fsm_expire_timer;
 151         this->tl.data = (long)this;
 152 #if FSM_TIMER_DEBUG
 153         printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
 154                this);
 155 #endif
 156         init_timer(&this->tl);
 157 }
 158
 159 void
 160 fsm_deltimer(fsm_timer *this)
 161 {
 162 #if FSM_TIMER_DEBUG
 163         printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
 164                 this);
 165 #endif
 166         del_timer(&this->tl);
 167 }
 168
 169 int
 170 fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
 171 {
 172
 173 #if FSM_TIMER_DEBUG
 174         printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
 175                this->fi->name, this, millisec);
 176 #endif
 177
 178         init_timer(&this->tl);
 179         this->tl.function = (void *)fsm_expire_timer;
 180         this->tl.data = (long)this;
 181         this->expire_event = event;
 182         this->event_arg = arg;
 183         this->tl.expires = jiffies + (millisec * HZ) / 1000;
 184         add_timer(&this->tl);
 185         return 0;
 186 }
 187
 188 /* FIXME: this function is never used, why */
 189 void
 190 fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
 191 {
 192
 193 #if FSM_TIMER_DEBUG
 194         printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
 195                 this->fi->name, this, millisec);
 196 #endif
 197
 198         del_timer(&this->tl);
 199         init_timer(&this->tl);
 200         this->tl.function = (void *)fsm_expire_timer;
 201         this->tl.data = (long)this;
 202         this->expire_event = event;
 203         this->event_arg = arg;
 204         this->tl.expires = jiffies + (millisec * HZ) / 1000;
 205         add_timer(&this->tl);
 206 }
 207
 208 EXPORT_SYMBOL(init_fsm);
 209 EXPORT_SYMBOL(kfree_fsm);
 210 EXPORT_SYMBOL(fsm_settimer);
 211 EXPORT_SYMBOL(fsm_deltimer);
 212 EXPORT_SYMBOL(fsm_addtimer);
 213 EXPORT_SYMBOL(fsm_modtimer);
 214 EXPORT_SYMBOL(fsm_getstate_str);
 215
 216 #if FSM_DEBUG_HISTORY
 217 EXPORT_SYMBOL(fsm_print_history);
 218 EXPORT_SYMBOL(fsm_record_history);
 219 #endif