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12#include <linux/cdev.h>
13#include <linux/device.h>
14#include <linux/fs.h>
15#include <linux/idr.h>
16#include <linux/kernel.h>
17#include <linux/module.h>
18#include <linux/poll.h>
19#include <linux/rpmsg.h>
20#include <linux/skbuff.h>
21#include <linux/slab.h>
22#include <linux/uaccess.h>
23#include <uapi/linux/rpmsg.h>
24
25#include "rpmsg_internal.h"
26
27#define RPMSG_DEV_MAX (MINORMASK + 1)
28
29static dev_t rpmsg_major;
30static struct class *rpmsg_class;
31
32static DEFINE_IDA(rpmsg_ctrl_ida);
33static DEFINE_IDA(rpmsg_ept_ida);
34static DEFINE_IDA(rpmsg_minor_ida);
35
36#define dev_to_eptdev(dev) container_of(dev, struct rpmsg_eptdev, dev)
37#define cdev_to_eptdev(i_cdev) container_of(i_cdev, struct rpmsg_eptdev, cdev)
38
39#define dev_to_ctrldev(dev) container_of(dev, struct rpmsg_ctrldev, dev)
40#define cdev_to_ctrldev(i_cdev) container_of(i_cdev, struct rpmsg_ctrldev, cdev)
41
42
43
44
45
46
47
48struct rpmsg_ctrldev {
49 struct rpmsg_device *rpdev;
50 struct cdev cdev;
51 struct device dev;
52};
53
54
55
56
57
58
59
60
61
62
63
64
65
66struct rpmsg_eptdev {
67 struct device dev;
68 struct cdev cdev;
69
70 struct rpmsg_device *rpdev;
71 struct rpmsg_channel_info chinfo;
72
73 struct mutex ept_lock;
74 struct rpmsg_endpoint *ept;
75
76 spinlock_t queue_lock;
77 struct sk_buff_head queue;
78 wait_queue_head_t readq;
79};
80
81static int rpmsg_eptdev_destroy(struct device *dev, void *data)
82{
83 struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
84
85 mutex_lock(&eptdev->ept_lock);
86 if (eptdev->ept) {
87 rpmsg_destroy_ept(eptdev->ept);
88 eptdev->ept = NULL;
89 }
90 mutex_unlock(&eptdev->ept_lock);
91
92
93 wake_up_interruptible(&eptdev->readq);
94
95 device_del(&eptdev->dev);
96 put_device(&eptdev->dev);
97
98 return 0;
99}
100
101static int rpmsg_ept_cb(struct rpmsg_device *rpdev, void *buf, int len,
102 void *priv, u32 addr)
103{
104 struct rpmsg_eptdev *eptdev = priv;
105 struct sk_buff *skb;
106
107 skb = alloc_skb(len, GFP_ATOMIC);
108 if (!skb)
109 return -ENOMEM;
110
111 skb_put_data(skb, buf, len);
112
113 spin_lock(&eptdev->queue_lock);
114 skb_queue_tail(&eptdev->queue, skb);
115 spin_unlock(&eptdev->queue_lock);
116
117
118 wake_up_interruptible(&eptdev->readq);
119
120 return 0;
121}
122
123static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
124{
125 struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
126 struct rpmsg_endpoint *ept;
127 struct rpmsg_device *rpdev = eptdev->rpdev;
128 struct device *dev = &eptdev->dev;
129
130 if (eptdev->ept)
131 return -EBUSY;
132
133 get_device(dev);
134
135 ept = rpmsg_create_ept(rpdev, rpmsg_ept_cb, eptdev, eptdev->chinfo);
136 if (!ept) {
137 dev_err(dev, "failed to open %s\n", eptdev->chinfo.name);
138 put_device(dev);
139 return -EINVAL;
140 }
141
142 eptdev->ept = ept;
143 filp->private_data = eptdev;
144
145 return 0;
146}
147
148static int rpmsg_eptdev_release(struct inode *inode, struct file *filp)
149{
150 struct rpmsg_eptdev *eptdev = cdev_to_eptdev(inode->i_cdev);
151 struct device *dev = &eptdev->dev;
152
153
154 mutex_lock(&eptdev->ept_lock);
155 if (eptdev->ept) {
156 rpmsg_destroy_ept(eptdev->ept);
157 eptdev->ept = NULL;
158 }
159 mutex_unlock(&eptdev->ept_lock);
160
161
162 skb_queue_purge(&eptdev->queue);
163
164 put_device(dev);
165
166 return 0;
167}
168
169static ssize_t rpmsg_eptdev_read_iter(struct kiocb *iocb, struct iov_iter *to)
170{
171 struct file *filp = iocb->ki_filp;
172 struct rpmsg_eptdev *eptdev = filp->private_data;
173 unsigned long flags;
174 struct sk_buff *skb;
175 int use;
176
177 if (!eptdev->ept)
178 return -EPIPE;
179
180 spin_lock_irqsave(&eptdev->queue_lock, flags);
181
182
183 if (skb_queue_empty(&eptdev->queue)) {
184 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
185
186 if (filp->f_flags & O_NONBLOCK)
187 return -EAGAIN;
188
189
190 if (wait_event_interruptible(eptdev->readq,
191 !skb_queue_empty(&eptdev->queue) ||
192 !eptdev->ept))
193 return -ERESTARTSYS;
194
195
196 if (!eptdev->ept)
197 return -EPIPE;
198
199 spin_lock_irqsave(&eptdev->queue_lock, flags);
200 }
201
202 skb = skb_dequeue(&eptdev->queue);
203 spin_unlock_irqrestore(&eptdev->queue_lock, flags);
204 if (!skb)
205 return -EFAULT;
206
207 use = min_t(size_t, iov_iter_count(to), skb->len);
208 if (copy_to_iter(skb->data, use, to) != use)
209 use = -EFAULT;
210
211 kfree_skb(skb);
212
213 return use;
214}
215
216static ssize_t rpmsg_eptdev_write_iter(struct kiocb *iocb,
217 struct iov_iter *from)
218{
219 struct file *filp = iocb->ki_filp;
220 struct rpmsg_eptdev *eptdev = filp->private_data;
221 size_t len = iov_iter_count(from);
222 void *kbuf;
223 int ret;
224
225 kbuf = kzalloc(len, GFP_KERNEL);
226 if (!kbuf)
227 return -ENOMEM;
228
229 if (!copy_from_iter_full(kbuf, len, from)) {
230 ret = -EFAULT;
231 goto free_kbuf;
232 }
233
234 if (mutex_lock_interruptible(&eptdev->ept_lock)) {
235 ret = -ERESTARTSYS;
236 goto free_kbuf;
237 }
238
239 if (!eptdev->ept) {
240 ret = -EPIPE;
241 goto unlock_eptdev;
242 }
243
244 if (filp->f_flags & O_NONBLOCK)
245 ret = rpmsg_trysendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
246 else
247 ret = rpmsg_sendto(eptdev->ept, kbuf, len, eptdev->chinfo.dst);
248
249unlock_eptdev:
250 mutex_unlock(&eptdev->ept_lock);
251
252free_kbuf:
253 kfree(kbuf);
254 return ret < 0 ? ret : len;
255}
256
257static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
258{
259 struct rpmsg_eptdev *eptdev = filp->private_data;
260 __poll_t mask = 0;
261
262 if (!eptdev->ept)
263 return EPOLLERR;
264
265 poll_wait(filp, &eptdev->readq, wait);
266
267 if (!skb_queue_empty(&eptdev->queue))
268 mask |= EPOLLIN | EPOLLRDNORM;
269
270 mask |= rpmsg_poll(eptdev->ept, filp, wait);
271
272 return mask;
273}
274
275static long rpmsg_eptdev_ioctl(struct file *fp, unsigned int cmd,
276 unsigned long arg)
277{
278 struct rpmsg_eptdev *eptdev = fp->private_data;
279
280 if (cmd != RPMSG_DESTROY_EPT_IOCTL)
281 return -EINVAL;
282
283 return rpmsg_eptdev_destroy(&eptdev->dev, NULL);
284}
285
286static const struct file_operations rpmsg_eptdev_fops = {
287 .owner = THIS_MODULE,
288 .open = rpmsg_eptdev_open,
289 .release = rpmsg_eptdev_release,
290 .read_iter = rpmsg_eptdev_read_iter,
291 .write_iter = rpmsg_eptdev_write_iter,
292 .poll = rpmsg_eptdev_poll,
293 .unlocked_ioctl = rpmsg_eptdev_ioctl,
294 .compat_ioctl = compat_ptr_ioctl,
295};
296
297static ssize_t name_show(struct device *dev, struct device_attribute *attr,
298 char *buf)
299{
300 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
301
302 return sprintf(buf, "%s\n", eptdev->chinfo.name);
303}
304static DEVICE_ATTR_RO(name);
305
306static ssize_t src_show(struct device *dev, struct device_attribute *attr,
307 char *buf)
308{
309 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
310
311 return sprintf(buf, "%d\n", eptdev->chinfo.src);
312}
313static DEVICE_ATTR_RO(src);
314
315static ssize_t dst_show(struct device *dev, struct device_attribute *attr,
316 char *buf)
317{
318 struct rpmsg_eptdev *eptdev = dev_get_drvdata(dev);
319
320 return sprintf(buf, "%d\n", eptdev->chinfo.dst);
321}
322static DEVICE_ATTR_RO(dst);
323
324static struct attribute *rpmsg_eptdev_attrs[] = {
325 &dev_attr_name.attr,
326 &dev_attr_src.attr,
327 &dev_attr_dst.attr,
328 NULL
329};
330ATTRIBUTE_GROUPS(rpmsg_eptdev);
331
332static void rpmsg_eptdev_release_device(struct device *dev)
333{
334 struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
335
336 ida_simple_remove(&rpmsg_ept_ida, dev->id);
337 ida_simple_remove(&rpmsg_minor_ida, MINOR(eptdev->dev.devt));
338 cdev_del(&eptdev->cdev);
339 kfree(eptdev);
340}
341
342static int rpmsg_eptdev_create(struct rpmsg_ctrldev *ctrldev,
343 struct rpmsg_channel_info chinfo)
344{
345 struct rpmsg_device *rpdev = ctrldev->rpdev;
346 struct rpmsg_eptdev *eptdev;
347 struct device *dev;
348 int ret;
349
350 eptdev = kzalloc(sizeof(*eptdev), GFP_KERNEL);
351 if (!eptdev)
352 return -ENOMEM;
353
354 dev = &eptdev->dev;
355 eptdev->rpdev = rpdev;
356 eptdev->chinfo = chinfo;
357
358 mutex_init(&eptdev->ept_lock);
359 spin_lock_init(&eptdev->queue_lock);
360 skb_queue_head_init(&eptdev->queue);
361 init_waitqueue_head(&eptdev->readq);
362
363 device_initialize(dev);
364 dev->class = rpmsg_class;
365 dev->parent = &ctrldev->dev;
366 dev->groups = rpmsg_eptdev_groups;
367 dev_set_drvdata(dev, eptdev);
368
369 cdev_init(&eptdev->cdev, &rpmsg_eptdev_fops);
370 eptdev->cdev.owner = THIS_MODULE;
371
372 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
373 if (ret < 0)
374 goto free_eptdev;
375 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
376
377 ret = ida_simple_get(&rpmsg_ept_ida, 0, 0, GFP_KERNEL);
378 if (ret < 0)
379 goto free_minor_ida;
380 dev->id = ret;
381 dev_set_name(dev, "rpmsg%d", ret);
382
383 ret = cdev_add(&eptdev->cdev, dev->devt, 1);
384 if (ret)
385 goto free_ept_ida;
386
387
388 dev->release = rpmsg_eptdev_release_device;
389
390 ret = device_add(dev);
391 if (ret) {
392 dev_err(dev, "device_add failed: %d\n", ret);
393 put_device(dev);
394 }
395
396 return ret;
397
398free_ept_ida:
399 ida_simple_remove(&rpmsg_ept_ida, dev->id);
400free_minor_ida:
401 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
402free_eptdev:
403 put_device(dev);
404 kfree(eptdev);
405
406 return ret;
407}
408
409static int rpmsg_ctrldev_open(struct inode *inode, struct file *filp)
410{
411 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
412
413 get_device(&ctrldev->dev);
414 filp->private_data = ctrldev;
415
416 return 0;
417}
418
419static int rpmsg_ctrldev_release(struct inode *inode, struct file *filp)
420{
421 struct rpmsg_ctrldev *ctrldev = cdev_to_ctrldev(inode->i_cdev);
422
423 put_device(&ctrldev->dev);
424
425 return 0;
426}
427
428static long rpmsg_ctrldev_ioctl(struct file *fp, unsigned int cmd,
429 unsigned long arg)
430{
431 struct rpmsg_ctrldev *ctrldev = fp->private_data;
432 void __user *argp = (void __user *)arg;
433 struct rpmsg_endpoint_info eptinfo;
434 struct rpmsg_channel_info chinfo;
435
436 if (cmd != RPMSG_CREATE_EPT_IOCTL)
437 return -EINVAL;
438
439 if (copy_from_user(&eptinfo, argp, sizeof(eptinfo)))
440 return -EFAULT;
441
442 memcpy(chinfo.name, eptinfo.name, RPMSG_NAME_SIZE);
443 chinfo.name[RPMSG_NAME_SIZE-1] = '\0';
444 chinfo.src = eptinfo.src;
445 chinfo.dst = eptinfo.dst;
446
447 return rpmsg_eptdev_create(ctrldev, chinfo);
448};
449
450static const struct file_operations rpmsg_ctrldev_fops = {
451 .owner = THIS_MODULE,
452 .open = rpmsg_ctrldev_open,
453 .release = rpmsg_ctrldev_release,
454 .unlocked_ioctl = rpmsg_ctrldev_ioctl,
455 .compat_ioctl = compat_ptr_ioctl,
456};
457
458static void rpmsg_ctrldev_release_device(struct device *dev)
459{
460 struct rpmsg_ctrldev *ctrldev = dev_to_ctrldev(dev);
461
462 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
463 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
464 cdev_del(&ctrldev->cdev);
465 kfree(ctrldev);
466}
467
468static int rpmsg_chrdev_probe(struct rpmsg_device *rpdev)
469{
470 struct rpmsg_ctrldev *ctrldev;
471 struct device *dev;
472 int ret;
473
474 ctrldev = kzalloc(sizeof(*ctrldev), GFP_KERNEL);
475 if (!ctrldev)
476 return -ENOMEM;
477
478 ctrldev->rpdev = rpdev;
479
480 dev = &ctrldev->dev;
481 device_initialize(dev);
482 dev->parent = &rpdev->dev;
483 dev->class = rpmsg_class;
484
485 cdev_init(&ctrldev->cdev, &rpmsg_ctrldev_fops);
486 ctrldev->cdev.owner = THIS_MODULE;
487
488 ret = ida_simple_get(&rpmsg_minor_ida, 0, RPMSG_DEV_MAX, GFP_KERNEL);
489 if (ret < 0)
490 goto free_ctrldev;
491 dev->devt = MKDEV(MAJOR(rpmsg_major), ret);
492
493 ret = ida_simple_get(&rpmsg_ctrl_ida, 0, 0, GFP_KERNEL);
494 if (ret < 0)
495 goto free_minor_ida;
496 dev->id = ret;
497 dev_set_name(&ctrldev->dev, "rpmsg_ctrl%d", ret);
498
499 ret = cdev_add(&ctrldev->cdev, dev->devt, 1);
500 if (ret)
501 goto free_ctrl_ida;
502
503
504 dev->release = rpmsg_ctrldev_release_device;
505
506 ret = device_add(dev);
507 if (ret) {
508 dev_err(&rpdev->dev, "device_add failed: %d\n", ret);
509 put_device(dev);
510 }
511
512 dev_set_drvdata(&rpdev->dev, ctrldev);
513
514 return ret;
515
516free_ctrl_ida:
517 ida_simple_remove(&rpmsg_ctrl_ida, dev->id);
518free_minor_ida:
519 ida_simple_remove(&rpmsg_minor_ida, MINOR(dev->devt));
520free_ctrldev:
521 put_device(dev);
522 kfree(ctrldev);
523
524 return ret;
525}
526
527static void rpmsg_chrdev_remove(struct rpmsg_device *rpdev)
528{
529 struct rpmsg_ctrldev *ctrldev = dev_get_drvdata(&rpdev->dev);
530 int ret;
531
532
533 ret = device_for_each_child(&ctrldev->dev, NULL, rpmsg_eptdev_destroy);
534 if (ret)
535 dev_warn(&rpdev->dev, "failed to nuke endpoints: %d\n", ret);
536
537 device_del(&ctrldev->dev);
538 put_device(&ctrldev->dev);
539}
540
541static struct rpmsg_driver rpmsg_chrdev_driver = {
542 .probe = rpmsg_chrdev_probe,
543 .remove = rpmsg_chrdev_remove,
544 .drv = {
545 .name = "rpmsg_chrdev",
546 },
547};
548
549static int rpmsg_chrdev_init(void)
550{
551 int ret;
552
553 ret = alloc_chrdev_region(&rpmsg_major, 0, RPMSG_DEV_MAX, "rpmsg");
554 if (ret < 0) {
555 pr_err("rpmsg: failed to allocate char dev region\n");
556 return ret;
557 }
558
559 rpmsg_class = class_create(THIS_MODULE, "rpmsg");
560 if (IS_ERR(rpmsg_class)) {
561 pr_err("failed to create rpmsg class\n");
562 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
563 return PTR_ERR(rpmsg_class);
564 }
565
566 ret = register_rpmsg_driver(&rpmsg_chrdev_driver);
567 if (ret < 0) {
568 pr_err("rpmsgchr: failed to register rpmsg driver\n");
569 class_destroy(rpmsg_class);
570 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
571 }
572
573 return ret;
574}
575postcore_initcall(rpmsg_chrdev_init);
576
577static void rpmsg_chrdev_exit(void)
578{
579 unregister_rpmsg_driver(&rpmsg_chrdev_driver);
580 class_destroy(rpmsg_class);
581 unregister_chrdev_region(rpmsg_major, RPMSG_DEV_MAX);
582}
583module_exit(rpmsg_chrdev_exit);
584
585MODULE_ALIAS("rpmsg:rpmsg_chrdev");
586MODULE_LICENSE("GPL v2");
587
