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v3.1
  1/*
  2 *
  3 *  Bluetooth virtual HCI driver
  4 *
  5 *  Copyright (C) 2000-2001  Qualcomm Incorporated
  6 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
  7 *  Copyright (C) 2004-2006  Marcel Holtmann <marcel@holtmann.org>
  8 *
  9 *
 10 *  This program is free software; you can redistribute it and/or modify
 11 *  it under the terms of the GNU General Public License as published by
 12 *  the Free Software Foundation; either version 2 of the License, or
 13 *  (at your option) any later version.
 14 *
 15 *  This program is distributed in the hope that it will be useful,
 16 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 17 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 18 *  GNU General Public License for more details.
 19 *
 20 *  You should have received a copy of the GNU General Public License
 21 *  along with this program; if not, write to the Free Software
 22 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 23 *
 24 */
 25
 26#include <linux/module.h>
 
 27
 28#include <linux/kernel.h>
 29#include <linux/init.h>
 30#include <linux/slab.h>
 31#include <linux/types.h>
 32#include <linux/errno.h>
 33#include <linux/sched.h>
 34#include <linux/poll.h>
 35
 36#include <linux/skbuff.h>
 37#include <linux/miscdevice.h>
 38
 39#include <net/bluetooth/bluetooth.h>
 40#include <net/bluetooth/hci_core.h>
 41
 42#define VERSION "1.3"
 
 
 43
 44struct vhci_data {
 45	struct hci_dev *hdev;
 46
 47	unsigned long flags;
 48
 49	wait_queue_head_t read_wait;
 50	struct sk_buff_head readq;
 
 
 51};
 52
 53static int vhci_open_dev(struct hci_dev *hdev)
 54{
 55	set_bit(HCI_RUNNING, &hdev->flags);
 56
 57	return 0;
 58}
 59
 60static int vhci_close_dev(struct hci_dev *hdev)
 61{
 62	struct vhci_data *data = hdev->driver_data;
 63
 64	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
 65		return 0;
 66
 67	skb_queue_purge(&data->readq);
 68
 69	return 0;
 70}
 71
 72static int vhci_flush(struct hci_dev *hdev)
 73{
 74	struct vhci_data *data = hdev->driver_data;
 75
 76	skb_queue_purge(&data->readq);
 77
 78	return 0;
 79}
 80
 81static int vhci_send_frame(struct sk_buff *skb)
 82{
 83	struct hci_dev* hdev = (struct hci_dev *) skb->dev;
 84	struct vhci_data *data;
 85
 86	if (!hdev) {
 87		BT_ERR("Frame for unknown HCI device (hdev=NULL)");
 88		return -ENODEV;
 89	}
 90
 91	if (!test_bit(HCI_RUNNING, &hdev->flags))
 92		return -EBUSY;
 93
 94	data = hdev->driver_data;
 95
 96	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
 97	skb_queue_tail(&data->readq, skb);
 98
 99	wake_up_interruptible(&data->read_wait);
100
101	return 0;
102}
103
104static void vhci_destruct(struct hci_dev *hdev)
105{
106	kfree(hdev->driver_data);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
107}
108
109static inline ssize_t vhci_get_user(struct vhci_data *data,
110					const char __user *buf, size_t count)
 
111{
 
112	struct sk_buff *skb;
 
 
 
113
114	if (count > HCI_MAX_FRAME_SIZE)
115		return -EINVAL;
116
117	skb = bt_skb_alloc(count, GFP_KERNEL);
118	if (!skb)
119		return -ENOMEM;
120
121	if (copy_from_user(skb_put(skb, count), buf, count)) {
122		kfree_skb(skb);
123		return -EFAULT;
 
 
 
124	}
125
126	skb->dev = (void *) data->hdev;
127	bt_cb(skb)->pkt_type = *((__u8 *) skb->data);
128	skb_pull(skb, 1);
129
130	hci_recv_frame(skb);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
131
132	return count;
 
 
 
 
 
133}
134
135static inline ssize_t vhci_put_user(struct vhci_data *data,
136			struct sk_buff *skb, char __user *buf, int count)
 
137{
138	char __user *ptr = buf;
139	int len, total = 0;
140
141	len = min_t(unsigned int, skb->len, count);
142
143	if (copy_to_user(ptr, skb->data, len))
144		return -EFAULT;
145
146	total += len;
 
147
148	data->hdev->stat.byte_tx += len;
149
150	switch (bt_cb(skb)->pkt_type) {
151	case HCI_COMMAND_PKT:
152		data->hdev->stat.cmd_tx++;
153		break;
154
155	case HCI_ACLDATA_PKT:
156		data->hdev->stat.acl_tx++;
157		break;
158
159	case HCI_SCODATA_PKT:
160		data->hdev->stat.sco_tx++;
161		break;
162	};
163
164	return total;
165}
166
167static ssize_t vhci_read(struct file *file,
168				char __user *buf, size_t count, loff_t *pos)
169{
170	struct vhci_data *data = file->private_data;
171	struct sk_buff *skb;
172	ssize_t ret = 0;
173
174	while (count) {
175		skb = skb_dequeue(&data->readq);
176		if (skb) {
177			ret = vhci_put_user(data, skb, buf, count);
178			if (ret < 0)
179				skb_queue_head(&data->readq, skb);
180			else
181				kfree_skb(skb);
182			break;
183		}
184
185		if (file->f_flags & O_NONBLOCK) {
186			ret = -EAGAIN;
187			break;
188		}
189
190		ret = wait_event_interruptible(data->read_wait,
191					!skb_queue_empty(&data->readq));
192		if (ret < 0)
193			break;
194	}
195
196	return ret;
197}
198
199static ssize_t vhci_write(struct file *file,
200			const char __user *buf, size_t count, loff_t *pos)
201{
 
202	struct vhci_data *data = file->private_data;
203
204	return vhci_get_user(data, buf, count);
205}
206
207static unsigned int vhci_poll(struct file *file, poll_table *wait)
208{
209	struct vhci_data *data = file->private_data;
210
211	poll_wait(file, &data->read_wait, wait);
212
213	if (!skb_queue_empty(&data->readq))
214		return POLLIN | POLLRDNORM;
215
216	return POLLOUT | POLLWRNORM;
217}
218
 
 
 
 
 
 
 
 
219static int vhci_open(struct inode *inode, struct file *file)
220{
221	struct vhci_data *data;
222	struct hci_dev *hdev;
223
224	data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
225	if (!data)
226		return -ENOMEM;
227
228	skb_queue_head_init(&data->readq);
229	init_waitqueue_head(&data->read_wait);
230
231	hdev = hci_alloc_dev();
232	if (!hdev) {
233		kfree(data);
234		return -ENOMEM;
235	}
236
237	data->hdev = hdev;
238
239	hdev->bus = HCI_VIRTUAL;
240	hdev->driver_data = data;
241
242	hdev->open     = vhci_open_dev;
243	hdev->close    = vhci_close_dev;
244	hdev->flush    = vhci_flush;
245	hdev->send     = vhci_send_frame;
246	hdev->destruct = vhci_destruct;
247
248	hdev->owner = THIS_MODULE;
249
250	if (hci_register_dev(hdev) < 0) {
251		BT_ERR("Can't register HCI device");
252		kfree(data);
253		hci_free_dev(hdev);
254		return -EBUSY;
255	}
256
257	file->private_data = data;
 
 
 
258
259	return nonseekable_open(inode, file);
260}
261
262static int vhci_release(struct inode *inode, struct file *file)
263{
264	struct vhci_data *data = file->private_data;
265	struct hci_dev *hdev = data->hdev;
266
267	if (hci_unregister_dev(hdev) < 0) {
268		BT_ERR("Can't unregister HCI device %s", hdev->name);
269	}
270
271	hci_free_dev(hdev);
 
 
 
272
273	file->private_data = NULL;
 
274
275	return 0;
276}
277
278static const struct file_operations vhci_fops = {
279	.owner		= THIS_MODULE,
280	.read		= vhci_read,
281	.write		= vhci_write,
282	.poll		= vhci_poll,
283	.open		= vhci_open,
284	.release	= vhci_release,
285	.llseek		= no_llseek,
286};
287
288static struct miscdevice vhci_miscdev= {
289	.name	= "vhci",
290	.fops	= &vhci_fops,
291	.minor	= MISC_DYNAMIC_MINOR,
292};
293
294static int __init vhci_init(void)
295{
296	BT_INFO("Virtual HCI driver ver %s", VERSION);
297
298	return misc_register(&vhci_miscdev);
299}
300
301static void __exit vhci_exit(void)
302{
303	misc_deregister(&vhci_miscdev);
304}
305
306module_init(vhci_init);
307module_exit(vhci_exit);
308
 
 
 
309MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
310MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
311MODULE_VERSION(VERSION);
312MODULE_LICENSE("GPL");
v3.15
  1/*
  2 *
  3 *  Bluetooth virtual HCI driver
  4 *
  5 *  Copyright (C) 2000-2001  Qualcomm Incorporated
  6 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
  7 *  Copyright (C) 2004-2006  Marcel Holtmann <marcel@holtmann.org>
  8 *
  9 *
 10 *  This program is free software; you can redistribute it and/or modify
 11 *  it under the terms of the GNU General Public License as published by
 12 *  the Free Software Foundation; either version 2 of the License, or
 13 *  (at your option) any later version.
 14 *
 15 *  This program is distributed in the hope that it will be useful,
 16 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 17 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 18 *  GNU General Public License for more details.
 19 *
 20 *  You should have received a copy of the GNU General Public License
 21 *  along with this program; if not, write to the Free Software
 22 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 23 *
 24 */
 25
 26#include <linux/module.h>
 27#include <asm/unaligned.h>
 28
 29#include <linux/kernel.h>
 30#include <linux/init.h>
 31#include <linux/slab.h>
 32#include <linux/types.h>
 33#include <linux/errno.h>
 34#include <linux/sched.h>
 35#include <linux/poll.h>
 36
 37#include <linux/skbuff.h>
 38#include <linux/miscdevice.h>
 39
 40#include <net/bluetooth/bluetooth.h>
 41#include <net/bluetooth/hci_core.h>
 42
 43#define VERSION "1.4"
 44
 45static bool amp;
 46
 47struct vhci_data {
 48	struct hci_dev *hdev;
 49
 
 
 50	wait_queue_head_t read_wait;
 51	struct sk_buff_head readq;
 52
 53	struct delayed_work open_timeout;
 54};
 55
 56static int vhci_open_dev(struct hci_dev *hdev)
 57{
 58	set_bit(HCI_RUNNING, &hdev->flags);
 59
 60	return 0;
 61}
 62
 63static int vhci_close_dev(struct hci_dev *hdev)
 64{
 65	struct vhci_data *data = hci_get_drvdata(hdev);
 66
 67	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
 68		return 0;
 69
 70	skb_queue_purge(&data->readq);
 71
 72	return 0;
 73}
 74
 75static int vhci_flush(struct hci_dev *hdev)
 76{
 77	struct vhci_data *data = hci_get_drvdata(hdev);
 78
 79	skb_queue_purge(&data->readq);
 80
 81	return 0;
 82}
 83
 84static int vhci_send_frame(struct hci_dev *hdev, struct sk_buff *skb)
 85{
 86	struct vhci_data *data = hci_get_drvdata(hdev);
 
 
 
 
 
 
 87
 88	if (!test_bit(HCI_RUNNING, &hdev->flags))
 89		return -EBUSY;
 90
 
 
 91	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
 92	skb_queue_tail(&data->readq, skb);
 93
 94	wake_up_interruptible(&data->read_wait);
 
 95	return 0;
 96}
 97
 98static int vhci_create_device(struct vhci_data *data, __u8 dev_type)
 99{
100	struct hci_dev *hdev;
101	struct sk_buff *skb;
102
103	skb = bt_skb_alloc(4, GFP_KERNEL);
104	if (!skb)
105		return -ENOMEM;
106
107	hdev = hci_alloc_dev();
108	if (!hdev) {
109		kfree_skb(skb);
110		return -ENOMEM;
111	}
112
113	data->hdev = hdev;
114
115	hdev->bus = HCI_VIRTUAL;
116	hdev->dev_type = dev_type;
117	hci_set_drvdata(hdev, data);
118
119	hdev->open  = vhci_open_dev;
120	hdev->close = vhci_close_dev;
121	hdev->flush = vhci_flush;
122	hdev->send  = vhci_send_frame;
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	bt_cb(skb)->pkt_type = HCI_VENDOR_PKT;
133
134	*skb_put(skb, 1) = 0xff;
135	*skb_put(skb, 1) = dev_type;
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 inline ssize_t vhci_get_user(struct vhci_data *data,
144				    const struct iovec *iov,
145				    unsigned long count)
146{
147	size_t len = iov_length(iov, count);
148	struct sk_buff *skb;
149	__u8 pkt_type, dev_type;
150	unsigned long i;
151	int ret;
152
153	if (len < 2 || len > HCI_MAX_FRAME_SIZE)
154		return -EINVAL;
155
156	skb = bt_skb_alloc(len, GFP_KERNEL);
157	if (!skb)
158		return -ENOMEM;
159
160	for (i = 0; i < count; i++) {
161		if (copy_from_user(skb_put(skb, iov[i].iov_len),
162				   iov[i].iov_base, iov[i].iov_len)) {
163			kfree_skb(skb);
164			return -EFAULT;
165		}
166	}
167
168	pkt_type = *((__u8 *) skb->data);
 
169	skb_pull(skb, 1);
170
171	switch (pkt_type) {
172	case HCI_EVENT_PKT:
173	case HCI_ACLDATA_PKT:
174	case HCI_SCODATA_PKT:
175		if (!data->hdev) {
176			kfree_skb(skb);
177			return -ENODEV;
178		}
179
180		bt_cb(skb)->pkt_type = pkt_type;
181
182		ret = hci_recv_frame(data->hdev, skb);
183		break;
184
185	case HCI_VENDOR_PKT:
186		if (data->hdev) {
187			kfree_skb(skb);
188			return -EBADFD;
189		}
190
191		cancel_delayed_work_sync(&data->open_timeout);
192
193		dev_type = *((__u8 *) skb->data);
194		skb_pull(skb, 1);
195
196		if (skb->len > 0) {
197			kfree_skb(skb);
198			return -EINVAL;
199		}
200
201		kfree_skb(skb);
202
203		if (dev_type != HCI_BREDR && dev_type != HCI_AMP)
204			return -EINVAL;
205
206		ret = vhci_create_device(data, dev_type);
207		break;
208
209	default:
210		kfree_skb(skb);
211		return -EINVAL;
212	}
213
214	return (ret < 0) ? ret : len;
215}
216
217static inline ssize_t vhci_put_user(struct vhci_data *data,
218				    struct sk_buff *skb,
219				    char __user *buf, int count)
220{
221	char __user *ptr = buf;
222	int len;
223
224	len = min_t(unsigned int, skb->len, count);
225
226	if (copy_to_user(ptr, skb->data, len))
227		return -EFAULT;
228
229	if (!data->hdev)
230		return len;
231
232	data->hdev->stat.byte_tx += len;
233
234	switch (bt_cb(skb)->pkt_type) {
235	case HCI_COMMAND_PKT:
236		data->hdev->stat.cmd_tx++;
237		break;
 
238	case HCI_ACLDATA_PKT:
239		data->hdev->stat.acl_tx++;
240		break;
 
241	case HCI_SCODATA_PKT:
242		data->hdev->stat.sco_tx++;
243		break;
244	}
245
246	return len;
247}
248
249static ssize_t vhci_read(struct file *file,
250			 char __user *buf, size_t count, loff_t *pos)
251{
252	struct vhci_data *data = file->private_data;
253	struct sk_buff *skb;
254	ssize_t ret = 0;
255
256	while (count) {
257		skb = skb_dequeue(&data->readq);
258		if (skb) {
259			ret = vhci_put_user(data, skb, buf, count);
260			if (ret < 0)
261				skb_queue_head(&data->readq, skb);
262			else
263				kfree_skb(skb);
264			break;
265		}
266
267		if (file->f_flags & O_NONBLOCK) {
268			ret = -EAGAIN;
269			break;
270		}
271
272		ret = wait_event_interruptible(data->read_wait,
273					       !skb_queue_empty(&data->readq));
274		if (ret < 0)
275			break;
276	}
277
278	return ret;
279}
280
281static ssize_t vhci_write(struct kiocb *iocb, const struct iovec *iov,
282			  unsigned long count, loff_t pos)
283{
284	struct file *file = iocb->ki_filp;
285	struct vhci_data *data = file->private_data;
286
287	return vhci_get_user(data, iov, count);
288}
289
290static unsigned int vhci_poll(struct file *file, poll_table *wait)
291{
292	struct vhci_data *data = file->private_data;
293
294	poll_wait(file, &data->read_wait, wait);
295
296	if (!skb_queue_empty(&data->readq))
297		return POLLIN | POLLRDNORM;
298
299	return POLLOUT | POLLWRNORM;
300}
301
302static void vhci_open_timeout(struct work_struct *work)
303{
304	struct vhci_data *data = container_of(work, struct vhci_data,
305					      open_timeout.work);
306
307	vhci_create_device(data, amp ? HCI_AMP : HCI_BREDR);
308}
309
310static int vhci_open(struct inode *inode, struct file *file)
311{
312	struct vhci_data *data;
 
313
314	data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
315	if (!data)
316		return -ENOMEM;
317
318	skb_queue_head_init(&data->readq);
319	init_waitqueue_head(&data->read_wait);
320
321	INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
322
323	file->private_data = data;
324	nonseekable_open(inode, file);
325
326	schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000));
327
328	return 0;
329}
330
331static int vhci_release(struct inode *inode, struct file *file)
332{
333	struct vhci_data *data = file->private_data;
334	struct hci_dev *hdev = data->hdev;
335
336	cancel_delayed_work_sync(&data->open_timeout);
 
 
337
338	if (hdev) {
339		hci_unregister_dev(hdev);
340		hci_free_dev(hdev);
341	}
342
343	file->private_data = NULL;
344	kfree(data);
345
346	return 0;
347}
348
349static const struct file_operations vhci_fops = {
350	.owner		= THIS_MODULE,
351	.read		= vhci_read,
352	.aio_write	= vhci_write,
353	.poll		= vhci_poll,
354	.open		= vhci_open,
355	.release	= vhci_release,
356	.llseek		= no_llseek,
357};
358
359static struct miscdevice vhci_miscdev= {
360	.name	= "vhci",
361	.fops	= &vhci_fops,
362	.minor	= VHCI_MINOR,
363};
364
365static int __init vhci_init(void)
366{
367	BT_INFO("Virtual HCI driver ver %s", VERSION);
368
369	return misc_register(&vhci_miscdev);
370}
371
372static void __exit vhci_exit(void)
373{
374	misc_deregister(&vhci_miscdev);
375}
376
377module_init(vhci_init);
378module_exit(vhci_exit);
379
380module_param(amp, bool, 0644);
381MODULE_PARM_DESC(amp, "Create AMP controller device");
382
383MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
384MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
385MODULE_VERSION(VERSION);
386MODULE_LICENSE("GPL");
387MODULE_ALIAS("devname:vhci");
388MODULE_ALIAS_MISCDEV(VHCI_MINOR);