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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *
  4 *  Bluetooth virtual HCI driver
  5 *
  6 *  Copyright (C) 2000-2001  Qualcomm Incorporated
  7 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
  8 *  Copyright (C) 2004-2006  Marcel Holtmann <marcel@holtmann.org>
  9 */
 10
 11#include <linux/module.h>
 12#include <linux/unaligned.h>
 13
 14#include <linux/atomic.h>
 15#include <linux/kernel.h>
 16#include <linux/init.h>
 17#include <linux/slab.h>
 18#include <linux/types.h>
 19#include <linux/errno.h>
 20#include <linux/sched.h>
 21#include <linux/poll.h>
 22
 23#include <linux/skbuff.h>
 24#include <linux/miscdevice.h>
 25#include <linux/debugfs.h>
 26
 27#include <net/bluetooth/bluetooth.h>
 28#include <net/bluetooth/hci_core.h>
 29
 30#define VERSION "1.5"
 31
 32static bool amp;
 33
 34struct vhci_data {
 35	struct hci_dev *hdev;
 36
 37	wait_queue_head_t read_wait;
 38	struct sk_buff_head readq;
 39
 40	struct mutex open_mutex;
 41	struct delayed_work open_timeout;
 42	struct work_struct suspend_work;
 43
 44	bool suspended;
 45	bool wakeup;
 46	__u16 msft_opcode;
 47	bool aosp_capable;
 48	atomic_t initialized;
 49};
 50
 51static int vhci_open_dev(struct hci_dev *hdev)
 52{
 53	return 0;
 54}
 55
 56static int vhci_close_dev(struct hci_dev *hdev)
 57{
 58	struct vhci_data *data = hci_get_drvdata(hdev);
 59
 60	skb_queue_purge(&data->readq);
 61
 62	return 0;
 63}
 64
 65static int vhci_flush(struct hci_dev *hdev)
 66{
 67	struct vhci_data *data = hci_get_drvdata(hdev);
 68
 69	skb_queue_purge(&data->readq);
 70
 71	return 0;
 72}
 73
 74static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 75{
 76	struct vhci_data *data = hci_get_drvdata(hdev);
 77
 78	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 79
 80	skb_queue_tail(&data->readq, skb);
 81
 82	if (atomic_read(&data->initialized))
 83		wake_up_interruptible(&data->read_wait);
 84	return 0;
 85}
 86
 87static int vhci_get_data_path_id(struct hci_dev *hdev, u8 *data_path_id)
 88{
 89	*data_path_id = 0;
 90	return 0;
 91}
 92
 93static int vhci_get_codec_config_data(struct hci_dev *hdev, __u8 type,
 94				      struct bt_codec *codec, __u8 *vnd_len,
 95				      __u8 **vnd_data)
 96{
 97	if (type != ESCO_LINK)
 98		return -EINVAL;
 99
100	*vnd_len = 0;
101	*vnd_data = NULL;
102	return 0;
103}
104
105static bool vhci_wakeup(struct hci_dev *hdev)
106{
107	struct vhci_data *data = hci_get_drvdata(hdev);
108
109	return data->wakeup;
110}
111
112static ssize_t force_suspend_read(struct file *file, char __user *user_buf,
113				  size_t count, loff_t *ppos)
114{
115	struct vhci_data *data = file->private_data;
116	char buf[3];
117
118	buf[0] = data->suspended ? 'Y' : 'N';
119	buf[1] = '\n';
120	buf[2] = '\0';
121	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
122}
123
124static void vhci_suspend_work(struct work_struct *work)
125{
126	struct vhci_data *data = container_of(work, struct vhci_data,
127					      suspend_work);
128
129	if (data->suspended)
130		hci_suspend_dev(data->hdev);
131	else
132		hci_resume_dev(data->hdev);
133}
134
135static ssize_t force_suspend_write(struct file *file,
136				   const char __user *user_buf,
137				   size_t count, loff_t *ppos)
138{
139	struct vhci_data *data = file->private_data;
140	bool enable;
141	int err;
142
143	err = kstrtobool_from_user(user_buf, count, &enable);
144	if (err)
145		return err;
146
147	if (data->suspended == enable)
148		return -EALREADY;
149
150	data->suspended = enable;
151
152	schedule_work(&data->suspend_work);
153
154	return count;
155}
156
157static const struct file_operations force_suspend_fops = {
158	.open		= simple_open,
159	.read		= force_suspend_read,
160	.write		= force_suspend_write,
161	.llseek		= default_llseek,
162};
163
164static ssize_t force_wakeup_read(struct file *file, char __user *user_buf,
165				 size_t count, loff_t *ppos)
166{
167	struct vhci_data *data = file->private_data;
168	char buf[3];
169
170	buf[0] = data->wakeup ? 'Y' : 'N';
171	buf[1] = '\n';
172	buf[2] = '\0';
173	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
174}
175
176static ssize_t force_wakeup_write(struct file *file,
177				  const char __user *user_buf, size_t count,
178				  loff_t *ppos)
179{
180	struct vhci_data *data = file->private_data;
181	bool enable;
182	int err;
183
184	err = kstrtobool_from_user(user_buf, count, &enable);
185	if (err)
186		return err;
187
188	if (data->wakeup == enable)
189		return -EALREADY;
190
191	data->wakeup = enable;
192
193	return count;
194}
195
196static const struct file_operations force_wakeup_fops = {
197	.open		= simple_open,
198	.read		= force_wakeup_read,
199	.write		= force_wakeup_write,
200	.llseek		= default_llseek,
201};
202
203static int msft_opcode_set(void *data, u64 val)
204{
205	struct vhci_data *vhci = data;
206
207	if (val > 0xffff || hci_opcode_ogf(val) != 0x3f)
208		return -EINVAL;
209
210	if (vhci->msft_opcode)
211		return -EALREADY;
212
213	vhci->msft_opcode = val;
214
215	return 0;
216}
217
218static int msft_opcode_get(void *data, u64 *val)
219{
220	struct vhci_data *vhci = data;
221
222	*val = vhci->msft_opcode;
223
224	return 0;
225}
226
227DEFINE_DEBUGFS_ATTRIBUTE(msft_opcode_fops, msft_opcode_get, msft_opcode_set,
228			 "%llu\n");
229
230static ssize_t aosp_capable_read(struct file *file, char __user *user_buf,
231				 size_t count, loff_t *ppos)
232{
233	struct vhci_data *vhci = file->private_data;
234	char buf[3];
235
236	buf[0] = vhci->aosp_capable ? 'Y' : 'N';
237	buf[1] = '\n';
238	buf[2] = '\0';
239	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
240}
241
242static ssize_t aosp_capable_write(struct file *file,
243				  const char __user *user_buf, size_t count,
244				  loff_t *ppos)
245{
246	struct vhci_data *vhci = file->private_data;
247	bool enable;
248	int err;
249
250	err = kstrtobool_from_user(user_buf, count, &enable);
251	if (err)
252		return err;
253
254	if (!enable)
255		return -EINVAL;
256
257	if (vhci->aosp_capable)
258		return -EALREADY;
259
260	vhci->aosp_capable = enable;
261
262	return count;
263}
264
265static const struct file_operations aosp_capable_fops = {
266	.open		= simple_open,
267	.read		= aosp_capable_read,
268	.write		= aosp_capable_write,
269	.llseek		= default_llseek,
270};
271
272static int vhci_setup(struct hci_dev *hdev)
273{
274	struct vhci_data *vhci = hci_get_drvdata(hdev);
275
276	if (vhci->msft_opcode)
277		hci_set_msft_opcode(hdev, vhci->msft_opcode);
278
279	if (vhci->aosp_capable)
280		hci_set_aosp_capable(hdev);
281
282	return 0;
283}
284
285static void vhci_coredump(struct hci_dev *hdev)
286{
287	/* No need to do anything */
288}
289
290static void vhci_coredump_hdr(struct hci_dev *hdev, struct sk_buff *skb)
291{
292	char buf[80];
293
294	snprintf(buf, sizeof(buf), "Controller Name: vhci_ctrl\n");
295	skb_put_data(skb, buf, strlen(buf));
296
297	snprintf(buf, sizeof(buf), "Firmware Version: vhci_fw\n");
298	skb_put_data(skb, buf, strlen(buf));
299
300	snprintf(buf, sizeof(buf), "Driver: vhci_drv\n");
301	skb_put_data(skb, buf, strlen(buf));
302
303	snprintf(buf, sizeof(buf), "Vendor: vhci\n");
304	skb_put_data(skb, buf, strlen(buf));
305}
306
307#define MAX_COREDUMP_LINE_LEN	40
308
309struct devcoredump_test_data {
310	enum devcoredump_state state;
311	unsigned int timeout;
312	char data[MAX_COREDUMP_LINE_LEN];
313};
314
315static inline void force_devcd_timeout(struct hci_dev *hdev,
316				       unsigned int timeout)
317{
318#ifdef CONFIG_DEV_COREDUMP
319	hdev->dump.timeout = msecs_to_jiffies(timeout * 1000);
320#endif
321}
322
323static ssize_t force_devcd_write(struct file *file, const char __user *user_buf,
324				 size_t count, loff_t *ppos)
325{
326	struct vhci_data *data = file->private_data;
327	struct hci_dev *hdev = data->hdev;
328	struct sk_buff *skb = NULL;
329	struct devcoredump_test_data dump_data;
330	size_t data_size;
331	int ret;
332
333	if (count < offsetof(struct devcoredump_test_data, data) ||
334	    count > sizeof(dump_data))
335		return -EINVAL;
336
337	if (copy_from_user(&dump_data, user_buf, count))
338		return -EFAULT;
339
340	data_size = count - offsetof(struct devcoredump_test_data, data);
341	skb = alloc_skb(data_size, GFP_ATOMIC);
342	if (!skb)
343		return -ENOMEM;
344	skb_put_data(skb, &dump_data.data, data_size);
345
346	hci_devcd_register(hdev, vhci_coredump, vhci_coredump_hdr, NULL);
347
348	/* Force the devcoredump timeout */
349	if (dump_data.timeout)
350		force_devcd_timeout(hdev, dump_data.timeout);
351
352	ret = hci_devcd_init(hdev, skb->len);
353	if (ret) {
354		BT_ERR("Failed to generate devcoredump");
355		kfree_skb(skb);
356		return ret;
357	}
358
359	hci_devcd_append(hdev, skb);
360
361	switch (dump_data.state) {
362	case HCI_DEVCOREDUMP_DONE:
363		hci_devcd_complete(hdev);
364		break;
365	case HCI_DEVCOREDUMP_ABORT:
366		hci_devcd_abort(hdev);
367		break;
368	case HCI_DEVCOREDUMP_TIMEOUT:
369		/* Do nothing */
370		break;
371	default:
372		return -EINVAL;
373	}
374
375	return count;
376}
377
378static const struct file_operations force_devcoredump_fops = {
379	.open		= simple_open,
380	.write		= force_devcd_write,
381};
382
383static int __vhci_create_device(struct vhci_data *data, __u8 opcode)
384{
385	struct hci_dev *hdev;
386	struct sk_buff *skb;
 
387
388	if (data->hdev)
389		return -EBADFD;
390
 
 
 
 
 
 
391	/* bits 2-5 are reserved (must be zero) */
392	if (opcode & 0x3c)
393		return -EINVAL;
394
395	skb = bt_skb_alloc(4, GFP_KERNEL);
396	if (!skb)
397		return -ENOMEM;
398
399	hdev = hci_alloc_dev();
400	if (!hdev) {
401		kfree_skb(skb);
402		return -ENOMEM;
403	}
404
405	data->hdev = hdev;
406
407	hdev->bus = HCI_VIRTUAL;
 
408	hci_set_drvdata(hdev, data);
409
410	hdev->open  = vhci_open_dev;
411	hdev->close = vhci_close_dev;
412	hdev->flush = vhci_flush;
413	hdev->send  = vhci_send_frame;
414	hdev->get_data_path_id = vhci_get_data_path_id;
415	hdev->get_codec_config_data = vhci_get_codec_config_data;
416	hdev->wakeup = vhci_wakeup;
417	hdev->setup = vhci_setup;
418	set_bit(HCI_QUIRK_NON_PERSISTENT_SETUP, &hdev->quirks);
419
420	/* bit 6 is for external configuration */
421	if (opcode & 0x40)
422		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
423
424	/* bit 7 is for raw device */
425	if (opcode & 0x80)
426		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
427
428	if (hci_register_dev(hdev) < 0) {
429		BT_ERR("Can't register HCI device");
430		hci_free_dev(hdev);
431		data->hdev = NULL;
432		kfree_skb(skb);
433		return -EBUSY;
434	}
435
436	debugfs_create_file("force_suspend", 0644, hdev->debugfs, data,
437			    &force_suspend_fops);
438
439	debugfs_create_file("force_wakeup", 0644, hdev->debugfs, data,
440			    &force_wakeup_fops);
441
442	if (IS_ENABLED(CONFIG_BT_MSFTEXT))
443		debugfs_create_file("msft_opcode", 0644, hdev->debugfs, data,
444				    &msft_opcode_fops);
445
446	if (IS_ENABLED(CONFIG_BT_AOSPEXT))
447		debugfs_create_file("aosp_capable", 0644, hdev->debugfs, data,
448				    &aosp_capable_fops);
449
450	debugfs_create_file("force_devcoredump", 0644, hdev->debugfs, data,
451			    &force_devcoredump_fops);
452
453	hci_skb_pkt_type(skb) = HCI_VENDOR_PKT;
454
455	skb_put_u8(skb, 0xff);
456	skb_put_u8(skb, opcode);
457	put_unaligned_le16(hdev->id, skb_put(skb, 2));
458	skb_queue_head(&data->readq, skb);
459	atomic_inc(&data->initialized);
460
461	wake_up_interruptible(&data->read_wait);
462	return 0;
463}
464
465static int vhci_create_device(struct vhci_data *data, __u8 opcode)
466{
467	int err;
468
469	mutex_lock(&data->open_mutex);
470	err = __vhci_create_device(data, opcode);
471	mutex_unlock(&data->open_mutex);
472
473	return err;
474}
475
476static inline ssize_t vhci_get_user(struct vhci_data *data,
477				    struct iov_iter *from)
478{
479	size_t len = iov_iter_count(from);
480	struct sk_buff *skb;
481	__u8 pkt_type, opcode;
482	int ret;
483
484	if (len < 2 || len > HCI_MAX_FRAME_SIZE)
485		return -EINVAL;
486
487	skb = bt_skb_alloc(len, GFP_KERNEL);
488	if (!skb)
489		return -ENOMEM;
490
491	if (!copy_from_iter_full(skb_put(skb, len), len, from)) {
492		kfree_skb(skb);
493		return -EFAULT;
494	}
495
496	pkt_type = *((__u8 *) skb->data);
497	skb_pull(skb, 1);
498
499	switch (pkt_type) {
500	case HCI_EVENT_PKT:
501	case HCI_ACLDATA_PKT:
502	case HCI_SCODATA_PKT:
503	case HCI_ISODATA_PKT:
504		if (!data->hdev) {
505			kfree_skb(skb);
506			return -ENODEV;
507		}
508
509		hci_skb_pkt_type(skb) = pkt_type;
510
511		ret = hci_recv_frame(data->hdev, skb);
512		break;
513
514	case HCI_VENDOR_PKT:
515		cancel_delayed_work_sync(&data->open_timeout);
516
517		opcode = *((__u8 *) skb->data);
518		skb_pull(skb, 1);
519
520		if (skb->len > 0) {
521			kfree_skb(skb);
522			return -EINVAL;
523		}
524
525		kfree_skb(skb);
526
527		ret = vhci_create_device(data, opcode);
528		break;
529
530	default:
531		kfree_skb(skb);
532		return -EINVAL;
533	}
534
535	return (ret < 0) ? ret : len;
536}
537
538static inline ssize_t vhci_put_user(struct vhci_data *data,
539				    struct sk_buff *skb,
540				    char __user *buf, int count)
541{
542	char __user *ptr = buf;
543	int len;
544
545	len = min_t(unsigned int, skb->len, count);
546
547	if (copy_to_user(ptr, skb->data, len))
548		return -EFAULT;
549
550	if (!data->hdev)
551		return len;
552
553	data->hdev->stat.byte_tx += len;
554
555	switch (hci_skb_pkt_type(skb)) {
556	case HCI_COMMAND_PKT:
557		data->hdev->stat.cmd_tx++;
558		break;
559	case HCI_ACLDATA_PKT:
560		data->hdev->stat.acl_tx++;
561		break;
562	case HCI_SCODATA_PKT:
563		data->hdev->stat.sco_tx++;
564		break;
565	}
566
567	return len;
568}
569
570static ssize_t vhci_read(struct file *file,
571			 char __user *buf, size_t count, loff_t *pos)
572{
573	struct vhci_data *data = file->private_data;
574	struct sk_buff *skb;
575	ssize_t ret = 0;
576
577	while (count) {
578		skb = skb_dequeue(&data->readq);
579		if (skb) {
580			ret = vhci_put_user(data, skb, buf, count);
581			if (ret < 0)
582				skb_queue_head(&data->readq, skb);
583			else
584				kfree_skb(skb);
585			break;
586		}
587
588		if (file->f_flags & O_NONBLOCK) {
589			ret = -EAGAIN;
590			break;
591		}
592
593		ret = wait_event_interruptible(data->read_wait,
594					       !skb_queue_empty(&data->readq));
595		if (ret < 0)
596			break;
597	}
598
599	return ret;
600}
601
602static ssize_t vhci_write(struct kiocb *iocb, struct iov_iter *from)
603{
604	struct file *file = iocb->ki_filp;
605	struct vhci_data *data = file->private_data;
606
607	return vhci_get_user(data, from);
608}
609
610static __poll_t vhci_poll(struct file *file, poll_table *wait)
611{
612	struct vhci_data *data = file->private_data;
613
614	poll_wait(file, &data->read_wait, wait);
615
616	if (!skb_queue_empty(&data->readq))
617		return EPOLLIN | EPOLLRDNORM;
618
619	return EPOLLOUT | EPOLLWRNORM;
620}
621
622static void vhci_open_timeout(struct work_struct *work)
623{
624	struct vhci_data *data = container_of(work, struct vhci_data,
625					      open_timeout.work);
626
627	vhci_create_device(data, 0x00);
628}
629
630static int vhci_open(struct inode *inode, struct file *file)
631{
632	struct vhci_data *data;
633
634	data = kzalloc(sizeof(*data), GFP_KERNEL);
635	if (!data)
636		return -ENOMEM;
637
638	skb_queue_head_init(&data->readq);
639	init_waitqueue_head(&data->read_wait);
640
641	mutex_init(&data->open_mutex);
642	INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout);
643	INIT_WORK(&data->suspend_work, vhci_suspend_work);
644
645	file->private_data = data;
646	nonseekable_open(inode, file);
647
648	schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000));
649
650	return 0;
651}
652
653static int vhci_release(struct inode *inode, struct file *file)
654{
655	struct vhci_data *data = file->private_data;
656	struct hci_dev *hdev;
657
658	cancel_delayed_work_sync(&data->open_timeout);
659	flush_work(&data->suspend_work);
660
661	hdev = data->hdev;
662
663	if (hdev) {
664		hci_unregister_dev(hdev);
665		hci_free_dev(hdev);
666	}
667
668	skb_queue_purge(&data->readq);
669	file->private_data = NULL;
670	kfree(data);
671
672	return 0;
673}
674
675static const struct file_operations vhci_fops = {
676	.owner		= THIS_MODULE,
677	.read		= vhci_read,
678	.write_iter	= vhci_write,
679	.poll		= vhci_poll,
680	.open		= vhci_open,
681	.release	= vhci_release,
 
682};
683
684static struct miscdevice vhci_miscdev = {
685	.name	= "vhci",
686	.fops	= &vhci_fops,
687	.minor	= VHCI_MINOR,
688};
689module_misc_device(vhci_miscdev);
690
691module_param(amp, bool, 0644);
692MODULE_PARM_DESC(amp, "Create AMP controller device");
693
694MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
695MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
696MODULE_VERSION(VERSION);
697MODULE_LICENSE("GPL");
698MODULE_ALIAS("devname:vhci");
699MODULE_ALIAS_MISCDEV(VHCI_MINOR);
v5.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *
  4 *  Bluetooth virtual HCI driver
  5 *
  6 *  Copyright (C) 2000-2001  Qualcomm Incorporated
  7 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
  8 *  Copyright (C) 2004-2006  Marcel Holtmann <marcel@holtmann.org>
  9 */
 10
 11#include <linux/module.h>
 12#include <asm/unaligned.h>
 13
 
 14#include <linux/kernel.h>
 15#include <linux/init.h>
 16#include <linux/slab.h>
 17#include <linux/types.h>
 18#include <linux/errno.h>
 19#include <linux/sched.h>
 20#include <linux/poll.h>
 21
 22#include <linux/skbuff.h>
 23#include <linux/miscdevice.h>
 
 24
 25#include <net/bluetooth/bluetooth.h>
 26#include <net/bluetooth/hci_core.h>
 27
 28#define VERSION "1.5"
 29
 30static bool amp;
 31
 32struct vhci_data {
 33	struct hci_dev *hdev;
 34
 35	wait_queue_head_t read_wait;
 36	struct sk_buff_head readq;
 37
 38	struct mutex open_mutex;
 39	struct delayed_work open_timeout;
 
 
 
 
 
 
 
 40};
 41
 42static int vhci_open_dev(struct hci_dev *hdev)
 43{
 44	return 0;
 45}
 46
 47static int vhci_close_dev(struct hci_dev *hdev)
 48{
 49	struct vhci_data *data = hci_get_drvdata(hdev);
 50
 51	skb_queue_purge(&data->readq);
 52
 53	return 0;
 54}
 55
 56static int vhci_flush(struct hci_dev *hdev)
 57{
 58	struct vhci_data *data = hci_get_drvdata(hdev);
 59
 60	skb_queue_purge(&data->readq);
 61
 62	return 0;
 63}
 64
 65static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 66{
 67	struct vhci_data *data = hci_get_drvdata(hdev);
 68
 69	memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
 
 70	skb_queue_tail(&data->readq, skb);
 71
 72	wake_up_interruptible(&data->read_wait);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 73	return 0;
 74}
 75
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 76static int __vhci_create_device(struct vhci_data *data, __u8 opcode)
 77{
 78	struct hci_dev *hdev;
 79	struct sk_buff *skb;
 80	__u8 dev_type;
 81
 82	if (data->hdev)
 83		return -EBADFD;
 84
 85	/* bits 0-1 are dev_type (Primary or AMP) */
 86	dev_type = opcode & 0x03;
 87
 88	if (dev_type != HCI_PRIMARY && dev_type != HCI_AMP)
 89		return -EINVAL;
 90
 91	/* bits 2-5 are reserved (must be zero) */
 92	if (opcode & 0x3c)
 93		return -EINVAL;
 94
 95	skb = bt_skb_alloc(4, GFP_KERNEL);
 96	if (!skb)
 97		return -ENOMEM;
 98
 99	hdev = hci_alloc_dev();
100	if (!hdev) {
101		kfree_skb(skb);
102		return -ENOMEM;
103	}
104
105	data->hdev = hdev;
106
107	hdev->bus = HCI_VIRTUAL;
108	hdev->dev_type = dev_type;
109	hci_set_drvdata(hdev, data);
110
111	hdev->open  = vhci_open_dev;
112	hdev->close = vhci_close_dev;
113	hdev->flush = vhci_flush;
114	hdev->send  = vhci_send_frame;
 
 
 
 
 
115
116	/* bit 6 is for external configuration */
117	if (opcode & 0x40)
118		set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks);
119
120	/* bit 7 is for raw device */
121	if (opcode & 0x80)
122		set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks);
123
124	if (hci_register_dev(hdev) < 0) {
125		BT_ERR("Can't register HCI device");
126		hci_free_dev(hdev);
127		data->hdev = NULL;
128		kfree_skb(skb);
129		return -EBUSY;
130	}
131
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
132	hci_skb_pkt_type(skb) = HCI_VENDOR_PKT;
133
134	skb_put_u8(skb, 0xff);
135	skb_put_u8(skb, opcode);
136	put_unaligned_le16(hdev->id, skb_put(skb, 2));
137	skb_queue_tail(&data->readq, skb);
 
138
139	wake_up_interruptible(&data->read_wait);
140	return 0;
141}
142
143static int vhci_create_device(struct vhci_data *data, __u8 opcode)
144{
145	int err;
146
147	mutex_lock(&data->open_mutex);
148	err = __vhci_create_device(data, opcode);
149	mutex_unlock(&data->open_mutex);
150
151	return err;
152}
153
154static inline ssize_t vhci_get_user(struct vhci_data *data,
155				    struct iov_iter *from)
156{
157	size_t len = iov_iter_count(from);
158	struct sk_buff *skb;
159	__u8 pkt_type, opcode;
160	int ret;
161
162	if (len < 2 || len > HCI_MAX_FRAME_SIZE)
163		return -EINVAL;
164
165	skb = bt_skb_alloc(len, GFP_KERNEL);
166	if (!skb)
167		return -ENOMEM;
168
169	if (!copy_from_iter_full(skb_put(skb, len), len, from)) {
170		kfree_skb(skb);
171		return -EFAULT;
172	}
173
174	pkt_type = *((__u8 *) skb->data);
175	skb_pull(skb, 1);
176
177	switch (pkt_type) {
178	case HCI_EVENT_PKT:
179	case HCI_ACLDATA_PKT:
180	case HCI_SCODATA_PKT:
 
181		if (!data->hdev) {
182			kfree_skb(skb);
183			return -ENODEV;
184		}
185
186		hci_skb_pkt_type(skb) = pkt_type;
187
188		ret = hci_recv_frame(data->hdev, skb);
189		break;
190
191	case HCI_VENDOR_PKT:
192		cancel_delayed_work_sync(&data->open_timeout);
193
194		opcode = *((__u8 *) skb->data);
195		skb_pull(skb, 1);
196
197		if (skb->len > 0) {
198			kfree_skb(skb);
199			return -EINVAL;
200		}
201
202		kfree_skb(skb);
203
204		ret = vhci_create_device(data, opcode);
205		break;
206
207	default:
208		kfree_skb(skb);
209		return -EINVAL;
210	}
211
212	return (ret < 0) ? ret : len;
213}
214
215static inline ssize_t vhci_put_user(struct vhci_data *data,
216				    struct sk_buff *skb,
217				    char __user *buf, int count)
218{
219	char __user *ptr = buf;
220	int len;
221
222	len = min_t(unsigned int, skb->len, count);
223
224	if (copy_to_user(ptr, skb->data, len))
225		return -EFAULT;
226
227	if (!data->hdev)
228		return len;
229
230	data->hdev->stat.byte_tx += len;
231
232	switch (hci_skb_pkt_type(skb)) {
233	case HCI_COMMAND_PKT:
234		data->hdev->stat.cmd_tx++;
235		break;
236	case HCI_ACLDATA_PKT:
237		data->hdev->stat.acl_tx++;
238		break;
239	case HCI_SCODATA_PKT:
240		data->hdev->stat.sco_tx++;
241		break;
242	}
243
244	return len;
245}
246
247static ssize_t vhci_read(struct file *file,
248			 char __user *buf, size_t count, loff_t *pos)
249{
250	struct vhci_data *data = file->private_data;
251	struct sk_buff *skb;
252	ssize_t ret = 0;
253
254	while (count) {
255		skb = skb_dequeue(&data->readq);
256		if (skb) {
257			ret = vhci_put_user(data, skb, buf, count);
258			if (ret < 0)
259				skb_queue_head(&data->readq, skb);
260			else
261				kfree_skb(skb);
262			break;
263		}
264
265		if (file->f_flags & O_NONBLOCK) {
266			ret = -EAGAIN;
267			break;
268		}
269
270		ret = wait_event_interruptible(data->read_wait,
271					       !skb_queue_empty(&data->readq));
272		if (ret < 0)
273			break;
274	}
275
276	return ret;
277}
278
279static ssize_t vhci_write(struct kiocb *iocb, struct iov_iter *from)
280{
281	struct file *file = iocb->ki_filp;
282	struct vhci_data *data = file->private_data;
283
284	return vhci_get_user(data, from);
285}
286
287static __poll_t vhci_poll(struct file *file, poll_table *wait)
288{
289	struct vhci_data *data = file->private_data;
290
291	poll_wait(file, &data->read_wait, wait);
292
293	if (!skb_queue_empty(&data->readq))
294		return EPOLLIN | EPOLLRDNORM;
295
296	return EPOLLOUT | EPOLLWRNORM;
297}
298
299static void vhci_open_timeout(struct work_struct *work)
300{
301	struct vhci_data *data = container_of(work, struct vhci_data,
302					      open_timeout.work);
303
304	vhci_create_device(data, amp ? HCI_AMP : HCI_PRIMARY);
305}
306
307static int vhci_open(struct inode *inode, struct file *file)
308{
309	struct vhci_data *data;
310
311	data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
312	if (!data)
313		return -ENOMEM;
314
315	skb_queue_head_init(&data->readq);
316	init_waitqueue_head(&data->read_wait);
317
318	mutex_init(&data->open_mutex);
319	INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout);
 
320
321	file->private_data = data;
322	nonseekable_open(inode, file);
323
324	schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000));
325
326	return 0;
327}
328
329static int vhci_release(struct inode *inode, struct file *file)
330{
331	struct vhci_data *data = file->private_data;
332	struct hci_dev *hdev;
333
334	cancel_delayed_work_sync(&data->open_timeout);
 
335
336	hdev = data->hdev;
337
338	if (hdev) {
339		hci_unregister_dev(hdev);
340		hci_free_dev(hdev);
341	}
342
343	skb_queue_purge(&data->readq);
344	file->private_data = NULL;
345	kfree(data);
346
347	return 0;
348}
349
350static const struct file_operations vhci_fops = {
351	.owner		= THIS_MODULE,
352	.read		= vhci_read,
353	.write_iter	= vhci_write,
354	.poll		= vhci_poll,
355	.open		= vhci_open,
356	.release	= vhci_release,
357	.llseek		= no_llseek,
358};
359
360static struct miscdevice vhci_miscdev = {
361	.name	= "vhci",
362	.fops	= &vhci_fops,
363	.minor	= VHCI_MINOR,
364};
365module_misc_device(vhci_miscdev);
366
367module_param(amp, bool, 0644);
368MODULE_PARM_DESC(amp, "Create AMP controller device");
369
370MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
371MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
372MODULE_VERSION(VERSION);
373MODULE_LICENSE("GPL");
374MODULE_ALIAS("devname:vhci");
375MODULE_ALIAS_MISCDEV(VHCI_MINOR);