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20#include <linux/poll.h>
21#include <linux/vmalloc.h>
22#include <linux/slab.h>
23#include <linux/timer.h>
24#include <linux/miscdevice.h>
25#include <linux/module.h>
26#include <linux/mISDNif.h>
27#include <linux/mutex.h>
28#include <linux/sched/signal.h>
29
30#include "core.h"
31
32static DEFINE_MUTEX(mISDN_mutex);
33static u_int *debug;
34
35
36struct mISDNtimerdev {
37 int next_id;
38 struct list_head pending;
39 struct list_head expired;
40 wait_queue_head_t wait;
41 u_int work;
42 spinlock_t lock;
43};
44
45struct mISDNtimer {
46 struct list_head list;
47 struct mISDNtimerdev *dev;
48 struct timer_list tl;
49 int id;
50};
51
52static int
53mISDN_open(struct inode *ino, struct file *filep)
54{
55 struct mISDNtimerdev *dev;
56
57 if (*debug & DEBUG_TIMER)
58 printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
59 dev = kmalloc(sizeof(struct mISDNtimerdev) , GFP_KERNEL);
60 if (!dev)
61 return -ENOMEM;
62 dev->next_id = 1;
63 INIT_LIST_HEAD(&dev->pending);
64 INIT_LIST_HEAD(&dev->expired);
65 spin_lock_init(&dev->lock);
66 dev->work = 0;
67 init_waitqueue_head(&dev->wait);
68 filep->private_data = dev;
69 return nonseekable_open(ino, filep);
70}
71
72static int
73mISDN_close(struct inode *ino, struct file *filep)
74{
75 struct mISDNtimerdev *dev = filep->private_data;
76 struct list_head *list = &dev->pending;
77 struct mISDNtimer *timer, *next;
78
79 if (*debug & DEBUG_TIMER)
80 printk(KERN_DEBUG "%s(%p,%p)\n", __func__, ino, filep);
81
82 spin_lock_irq(&dev->lock);
83 while (!list_empty(list)) {
84 timer = list_first_entry(list, struct mISDNtimer, list);
85 spin_unlock_irq(&dev->lock);
86 del_timer_sync(&timer->tl);
87 spin_lock_irq(&dev->lock);
88
89 list_del(&timer->list);
90 kfree(timer);
91 }
92 spin_unlock_irq(&dev->lock);
93
94 list_for_each_entry_safe(timer, next, &dev->expired, list) {
95 kfree(timer);
96 }
97 kfree(dev);
98 return 0;
99}
100
101static ssize_t
102mISDN_read(struct file *filep, char __user *buf, size_t count, loff_t *off)
103{
104 struct mISDNtimerdev *dev = filep->private_data;
105 struct list_head *list = &dev->expired;
106 struct mISDNtimer *timer;
107 int ret = 0;
108
109 if (*debug & DEBUG_TIMER)
110 printk(KERN_DEBUG "%s(%p, %p, %d, %p)\n", __func__,
111 filep, buf, (int)count, off);
112
113 if (count < sizeof(int))
114 return -ENOSPC;
115
116 spin_lock_irq(&dev->lock);
117 while (list_empty(list) && (dev->work == 0)) {
118 spin_unlock_irq(&dev->lock);
119 if (filep->f_flags & O_NONBLOCK)
120 return -EAGAIN;
121 wait_event_interruptible(dev->wait, (dev->work ||
122 !list_empty(list)));
123 if (signal_pending(current))
124 return -ERESTARTSYS;
125 spin_lock_irq(&dev->lock);
126 }
127 if (dev->work)
128 dev->work = 0;
129 if (!list_empty(list)) {
130 timer = list_first_entry(list, struct mISDNtimer, list);
131 list_del(&timer->list);
132 spin_unlock_irq(&dev->lock);
133 if (put_user(timer->id, (int __user *)buf))
134 ret = -EFAULT;
135 else
136 ret = sizeof(int);
137 kfree(timer);
138 } else {
139 spin_unlock_irq(&dev->lock);
140 }
141 return ret;
142}
143
144static __poll_t
145mISDN_poll(struct file *filep, poll_table *wait)
146{
147 struct mISDNtimerdev *dev = filep->private_data;
148 __poll_t mask = EPOLLERR;
149
150 if (*debug & DEBUG_TIMER)
151 printk(KERN_DEBUG "%s(%p, %p)\n", __func__, filep, wait);
152 if (dev) {
153 poll_wait(filep, &dev->wait, wait);
154 mask = 0;
155 if (dev->work || !list_empty(&dev->expired))
156 mask |= (EPOLLIN | EPOLLRDNORM);
157 if (*debug & DEBUG_TIMER)
158 printk(KERN_DEBUG "%s work(%d) empty(%d)\n", __func__,
159 dev->work, list_empty(&dev->expired));
160 }
161 return mask;
162}
163
164static void
165dev_expire_timer(struct timer_list *t)
166{
167 struct mISDNtimer *timer = from_timer(timer, t, tl);
168 u_long flags;
169
170 spin_lock_irqsave(&timer->dev->lock, flags);
171 if (timer->id >= 0)
172 list_move_tail(&timer->list, &timer->dev->expired);
173 spin_unlock_irqrestore(&timer->dev->lock, flags);
174 wake_up_interruptible(&timer->dev->wait);
175}
176
177static int
178misdn_add_timer(struct mISDNtimerdev *dev, int timeout)
179{
180 int id;
181 struct mISDNtimer *timer;
182
183 if (!timeout) {
184 dev->work = 1;
185 wake_up_interruptible(&dev->wait);
186 id = 0;
187 } else {
188 timer = kzalloc(sizeof(struct mISDNtimer), GFP_KERNEL);
189 if (!timer)
190 return -ENOMEM;
191 timer->dev = dev;
192 timer_setup(&timer->tl, dev_expire_timer, 0);
193 spin_lock_irq(&dev->lock);
194 id = timer->id = dev->next_id++;
195 if (dev->next_id < 0)
196 dev->next_id = 1;
197 list_add_tail(&timer->list, &dev->pending);
198 timer->tl.expires = jiffies + ((HZ * (u_long)timeout) / 1000);
199 add_timer(&timer->tl);
200 spin_unlock_irq(&dev->lock);
201 }
202 return id;
203}
204
205static int
206misdn_del_timer(struct mISDNtimerdev *dev, int id)
207{
208 struct mISDNtimer *timer;
209
210 spin_lock_irq(&dev->lock);
211 list_for_each_entry(timer, &dev->pending, list) {
212 if (timer->id == id) {
213 list_del_init(&timer->list);
214 timer->id = -1;
215 spin_unlock_irq(&dev->lock);
216 del_timer_sync(&timer->tl);
217 kfree(timer);
218 return id;
219 }
220 }
221 spin_unlock_irq(&dev->lock);
222 return 0;
223}
224
225static long
226mISDN_ioctl(struct file *filep, unsigned int cmd, unsigned long arg)
227{
228 struct mISDNtimerdev *dev = filep->private_data;
229 int id, tout, ret = 0;
230
231
232 if (*debug & DEBUG_TIMER)
233 printk(KERN_DEBUG "%s(%p, %x, %lx)\n", __func__,
234 filep, cmd, arg);
235 mutex_lock(&mISDN_mutex);
236 switch (cmd) {
237 case IMADDTIMER:
238 if (get_user(tout, (int __user *)arg)) {
239 ret = -EFAULT;
240 break;
241 }
242 id = misdn_add_timer(dev, tout);
243 if (*debug & DEBUG_TIMER)
244 printk(KERN_DEBUG "%s add %d id %d\n", __func__,
245 tout, id);
246 if (id < 0) {
247 ret = id;
248 break;
249 }
250 if (put_user(id, (int __user *)arg))
251 ret = -EFAULT;
252 break;
253 case IMDELTIMER:
254 if (get_user(id, (int __user *)arg)) {
255 ret = -EFAULT;
256 break;
257 }
258 if (*debug & DEBUG_TIMER)
259 printk(KERN_DEBUG "%s del id %d\n", __func__, id);
260 id = misdn_del_timer(dev, id);
261 if (put_user(id, (int __user *)arg))
262 ret = -EFAULT;
263 break;
264 default:
265 ret = -EINVAL;
266 }
267 mutex_unlock(&mISDN_mutex);
268 return ret;
269}
270
271static const struct file_operations mISDN_fops = {
272 .owner = THIS_MODULE,
273 .read = mISDN_read,
274 .poll = mISDN_poll,
275 .unlocked_ioctl = mISDN_ioctl,
276 .open = mISDN_open,
277 .release = mISDN_close,
278 .llseek = no_llseek,
279};
280
281static struct miscdevice mISDNtimer = {
282 .minor = MISC_DYNAMIC_MINOR,
283 .name = "mISDNtimer",
284 .fops = &mISDN_fops,
285};
286
287int
288mISDN_inittimer(u_int *deb)
289{
290 int err;
291
292 debug = deb;
293 err = misc_register(&mISDNtimer);
294 if (err)
295 printk(KERN_WARNING "mISDN: Could not register timer device\n");
296 return err;
297}
298
299void mISDN_timer_cleanup(void)
300{
301 misc_deregister(&mISDNtimer);
302}
303
