summaryrefslogtreecommitdiffstats
path: root/drivers/bluetooth/hci_vhci.c
blob: 379d3025cf33c6e25de99cd01ce38334ac589612 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
/*
 *
 *  Bluetooth virtual HCI driver
 *
 *  Copyright (C) 2000-2001  Qualcomm Incorporated
 *  Copyright (C) 2002-2003  Maxim Krasnyansky <maxk@qualcomm.com>
 *  Copyright (C) 2004-2006  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/poll.h>

#include <linux/skbuff.h>
#include <linux/miscdevice.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#define VERSION "1.3"

static int minor = MISC_DYNAMIC_MINOR;

struct vhci_data {
	struct hci_dev *hdev;

	unsigned long flags;

	wait_queue_head_t read_wait;
	struct sk_buff_head readq;

	struct fasync_struct *fasync;
};

#define VHCI_FASYNC	0x0010

static struct miscdevice vhci_miscdev;

static int vhci_open_dev(struct hci_dev *hdev)
{
	set_bit(HCI_RUNNING, &hdev->flags);

	return 0;
}

static int vhci_close_dev(struct hci_dev *hdev)
{
	struct vhci_data *data = hdev->driver_data;

	if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
		return 0;

	skb_queue_purge(&data->readq);

	return 0;
}

static int vhci_flush(struct hci_dev *hdev)
{
	struct vhci_data *data = hdev->driver_data;

	skb_queue_purge(&data->readq);

	return 0;
}

static int vhci_send_frame(struct sk_buff *skb)
{
	struct hci_dev* hdev = (struct hci_dev *) skb->dev;
	struct vhci_data *data;

	if (!hdev) {
		BT_ERR("Frame for unknown HCI device (hdev=NULL)");
		return -ENODEV;
	}

	if (!test_bit(HCI_RUNNING, &hdev->flags))
		return -EBUSY;

	data = hdev->driver_data;

	memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
	skb_queue_tail(&data->readq, skb);

	if (data->flags & VHCI_FASYNC)
		kill_fasync(&data->fasync, SIGIO, POLL_IN);

	wake_up_interruptible(&data->read_wait);

	return 0;
}

static void vhci_destruct(struct hci_dev *hdev)
{
	kfree(hdev->driver_data);
}

static inline ssize_t vhci_get_user(struct vhci_data *data,
					const char __user *buf, size_t count)
{
	struct sk_buff *skb;

	if (count > HCI_MAX_FRAME_SIZE)
		return -EINVAL;

	skb = bt_skb_alloc(count, GFP_KERNEL);
	if (!skb)
		return -ENOMEM;

	if (copy_from_user(skb_put(skb, count), buf, count)) {
		kfree_skb(skb);
		return -EFAULT;
	}

	skb->dev = (void *) data->hdev;
	bt_cb(skb)->pkt_type = *((__u8 *) skb->data);
	skb_pull(skb, 1);

	hci_recv_frame(skb);

	return count;
}

static inline ssize_t vhci_put_user(struct vhci_data *data,
			struct sk_buff *skb, char __user *buf, int count)
{
	char __user *ptr = buf;
	int len, total = 0;

	len = min_t(unsigned int, skb->len, count);

	if (copy_to_user(ptr, skb->data, len))
		return -EFAULT;

	total += len;

	data->hdev->stat.byte_tx += len;

	switch (bt_cb(skb)->pkt_type) {
	case HCI_COMMAND_PKT:
		data->hdev->stat.cmd_tx++;
		break;

	case HCI_ACLDATA_PKT:
		data->hdev->stat.acl_tx++;
		break;

	case HCI_SCODATA_PKT:
		data->hdev->stat.cmd_tx++;
		break;
	};

	return total;
}

static ssize_t vhci_read(struct file *file,
				char __user *buf, size_t count, loff_t *pos)
{
	DECLARE_WAITQUEUE(wait, current);
	struct vhci_data *data = file->private_data;
	struct sk_buff *skb;
	ssize_t ret = 0;

	add_wait_queue(&data->read_wait, &wait);
	while (count) {
		set_current_state(TASK_INTERRUPTIBLE);

		skb = skb_dequeue(&data->readq);
		if (!skb) {
			if (file->f_flags & O_NONBLOCK) {
				ret = -EAGAIN;
				break;
			}

			if (signal_pending(current)) {
				ret = -ERESTARTSYS;
				break;
			}

			schedule();
			continue;
		}

		if (access_ok(VERIFY_WRITE, buf, count))
			ret = vhci_put_user(data, skb, buf, count);
		else
			ret = -EFAULT;

		kfree_skb(skb);
		break;
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&data->read_wait, &wait);

	return ret;
}

static ssize_t vhci_write(struct file *file,
			const char __user *buf, size_t count, loff_t *pos)
{
	struct vhci_data *data = file->private_data;

	if (!access_ok(VERIFY_READ, buf, count))
		return -EFAULT;

	return vhci_get_user(data, buf, count);
}

static unsigned int vhci_poll(struct file *file, poll_table *wait)
{
	struct vhci_data *data = file->private_data;

	poll_wait(file, &data->read_wait, wait);

	if (!skb_queue_empty(&data->readq))
		return POLLIN | POLLRDNORM;

	return POLLOUT | POLLWRNORM;
}

static int vhci_ioctl(struct inode *inode, struct file *file,
					unsigned int cmd, unsigned long arg)
{
	return -EINVAL;
}

static int vhci_open(struct inode *inode, struct file *file)
{
	struct vhci_data *data;
	struct hci_dev *hdev;

	data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	skb_queue_head_init(&data->readq);
	init_waitqueue_head(&data->read_wait);

	lock_kernel();
	hdev = hci_alloc_dev();
	if (!hdev) {
		kfree(data);
		unlock_kernel();
		return -ENOMEM;
	}

	data->hdev = hdev;

	hdev->type = HCI_VIRTUAL;
	hdev->driver_data = data;

	hdev->open     = vhci_open_dev;
	hdev->close    = vhci_close_dev;
	hdev->flush    = vhci_flush;
	hdev->send     = vhci_send_frame;
	hdev->destruct = vhci_destruct;

	hdev->owner = THIS_MODULE;

	if (hci_register_dev(hdev) < 0) {
		BT_ERR("Can't register HCI device");
		kfree(data);
		hci_free_dev(hdev);
		unlock_kernel();
		return -EBUSY;
	}

	file->private_data = data;
	unlock_kernel();

	return nonseekable_open(inode, file);
}

static int vhci_release(struct inode *inode, struct file *file)
{
	struct vhci_data *data = file->private_data;
	struct hci_dev *hdev = data->hdev;

	if (hci_unregister_dev(hdev) < 0) {
		BT_ERR("Can't unregister HCI device %s", hdev->name);
	}

	hci_free_dev(hdev);

	file->private_data = NULL;

	return 0;
}

static int vhci_fasync(int fd, struct file *file, int on)
{
	struct vhci_data *data = file->private_data;
	int err = 0;

	lock_kernel();
	err = fasync_helper(fd, file, on, &data->fasync);
	if (err < 0)
		goto out;

	if (on)
		data->flags |= VHCI_FASYNC;
	else
		data->flags &= ~VHCI_FASYNC;

out:
	unlock_kernel();
	return err;
}

static const struct file_operations vhci_fops = {
	.owner		= THIS_MODULE,
	.read		= vhci_read,
	.write		= vhci_write,
	.poll		= vhci_poll,
	.ioctl		= vhci_ioctl,
	.open		= vhci_open,
	.release	= vhci_release,
	.fasync		= vhci_fasync,
};

static struct miscdevice vhci_miscdev= {
	.name	= "vhci",
	.fops	= &vhci_fops,
	.minor	= MISC_DYNAMIC_MINOR,
};

static int __init vhci_init(void)
{
	BT_INFO("Virtual HCI driver ver %s", VERSION);

	if (misc_register(&vhci_miscdev) < 0) {
		BT_ERR("Can't register misc device with minor %d", minor);
		return -EIO;
	}

	return 0;
}

static void __exit vhci_exit(void)
{
	if (misc_deregister(&vhci_miscdev) < 0)
		BT_ERR("Can't unregister misc device with minor %d", minor);
}

module_init(vhci_init);
module_exit(vhci_exit);

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");