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                         if (this->f->jumpmatrix)
  82                                 kfree(this->f->jumpmatrix);
  83                         kfree(this->f);
  84                 }
  85                 kfree(this);
  86         } else
  87                 printk(KERN_WARNING
  88                         "fsm: kfree_fsm called with NULL argument\n");
  89 }
  90
  91 #if FSM_DEBUG_HISTORY
  92 void
  93 fsm_print_history(fsm_instance *fi)
  94 {
  95         int idx = 0;
  96         int i;
  97
  98         if (fi->history_size >= FSM_HISTORY_SIZE)
  99                 idx = fi->history_index;
 100
 101         printk(KERN_DEBUG "fsm(%s): History:\n", fi->name);
 102         for (i = 0; i < fi->history_size; i++) {
 103                 int e = fi->history[idx].event;
 104                 int s = fi->history[idx++].state;
 105                 idx %= FSM_HISTORY_SIZE;
 106                 if (e == -1)
 107                         printk(KERN_DEBUG "  S=%s\n",
 108                                fi->f->state_names[s]);
 109                 else
 110                         printk(KERN_DEBUG "  S=%s E=%s\n",
 111                                fi->f->state_names[s],
 112                                fi->f->event_names[e]);
 113         }
 114         fi->history_size = fi->history_index = 0;
 115 }
 116
 117 void
 118 fsm_record_history(fsm_instance *fi, int state, int event)
 119 {
 120         fi->history[fi->history_index].state = state;
 121         fi->history[fi->history_index++].event = event;
 122         fi->history_index %= FSM_HISTORY_SIZE;
 123         if (fi->history_size < FSM_HISTORY_SIZE)
 124                 fi->history_size++;
 125 }
 126 #endif
 127
 128 const char *
 129 fsm_getstate_str(fsm_instance *fi)
 130 {
 131         int st = atomic_read(&fi->state);
 132         if (st >= fi->f->nr_states)
 133                 return "Invalid";
 134         return fi->f->state_names[st];
 135 }
 136
 137 static void
 138 fsm_expire_timer(fsm_timer *this)
 139 {
 140 #if FSM_TIMER_DEBUG
 141         printk(KERN_DEBUG "fsm(%s): Timer %p expired\n",
 142                this->fi->name, this);
 143 #endif
 144         fsm_event(this->fi, this->expire_event, this->event_arg);
 145 }
 146
 147 void
 148 fsm_settimer(fsm_instance *fi, fsm_timer *this)
 149 {
 150         this->fi = fi;
 151         this->tl.function = (void *)fsm_expire_timer;
 152         this->tl.data = (long)this;
 153 #if FSM_TIMER_DEBUG
 154         printk(KERN_DEBUG "fsm(%s): Create timer %p\n", fi->name,
 155                this);
 156 #endif
 157         init_timer(&this->tl);
 158 }
 159
 160 void
 161 fsm_deltimer(fsm_timer *this)
 162 {
 163 #if FSM_TIMER_DEBUG
 164         printk(KERN_DEBUG "fsm(%s): Delete timer %p\n", this->fi->name,
 165                 this);
 166 #endif
 167         del_timer(&this->tl);
 168 }
 169
 170 int
 171 fsm_addtimer(fsm_timer *this, int millisec, int event, void *arg)
 172 {
 173
 174 #if FSM_TIMER_DEBUG
 175         printk(KERN_DEBUG "fsm(%s): Add timer %p %dms\n",
 176                this->fi->name, this, millisec);
 177 #endif
 178
 179         init_timer(&this->tl);
 180         this->tl.function = (void *)fsm_expire_timer;
 181         this->tl.data = (long)this;
 182         this->expire_event = event;
 183         this->event_arg = arg;
 184         this->tl.expires = jiffies + (millisec * HZ) / 1000;
 185         add_timer(&this->tl);
 186         return 0;
 187 }
 188
 189 /* FIXME: this function is never used, why */
 190 void
 191 fsm_modtimer(fsm_timer *this, int millisec, int event, void *arg)
 192 {
 193
 194 #if FSM_TIMER_DEBUG
 195         printk(KERN_DEBUG "fsm(%s): Restart timer %p %dms\n",
 196                 this->fi->name, this, millisec);
 197 #endif
 198
 199         del_timer(&this->tl);
 200         init_timer(&this->tl);
 201         this->tl.function = (void *)fsm_expire_timer;
 202         this->tl.data = (long)this;
 203         this->expire_event = event;
 204         this->event_arg = arg;
 205         this->tl.expires = jiffies + (millisec * HZ) / 1000;
 206         add_timer(&this->tl);
 207 }
 208
 209 EXPORT_SYMBOL(init_fsm);
 210 EXPORT_SYMBOL(kfree_fsm);
 211 EXPORT_SYMBOL(fsm_settimer);
 212 EXPORT_SYMBOL(fsm_deltimer);
 213 EXPORT_SYMBOL(fsm_addtimer);
 214 EXPORT_SYMBOL(fsm_modtimer);
 215 EXPORT_SYMBOL(fsm_getstate_str);
 216
 217 #if FSM_DEBUG_HISTORY
 218 EXPORT_SYMBOL(fsm_print_history);
 219 EXPORT_SYMBOL(fsm_record_history);
 220 #endif