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
44 static bool amp;
45
46 struct vhci_data {
47 struct hci_dev *hdev;
48
49 unsigned long flags;
50
51 wait_queue_head_t read_wait;
52 struct sk_buff_head readq;
53 };
54
vhci_open_dev(struct hci_dev * hdev)55 static int vhci_open_dev(struct hci_dev *hdev)
56 {
57 set_bit(HCI_RUNNING, &hdev->flags);
58
59 return 0;
60 }
61
vhci_close_dev(struct hci_dev * hdev)62 static int vhci_close_dev(struct hci_dev *hdev)
63 {
64 struct vhci_data *data = hdev->driver_data;
65
66 if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
67 return 0;
68
69 skb_queue_purge(&data->readq);
70
71 return 0;
72 }
73
vhci_flush(struct hci_dev * hdev)74 static int vhci_flush(struct hci_dev *hdev)
75 {
76 struct vhci_data *data = hdev->driver_data;
77
78 skb_queue_purge(&data->readq);
79
80 return 0;
81 }
82
vhci_send_frame(struct sk_buff * skb)83 static int vhci_send_frame(struct sk_buff *skb)
84 {
85 struct hci_dev* hdev = (struct hci_dev *) skb->dev;
86 struct vhci_data *data;
87
88 if (!hdev) {
89 BT_ERR("Frame for unknown HCI device (hdev=NULL)");
90 return -ENODEV;
91 }
92
93 if (!test_bit(HCI_RUNNING, &hdev->flags))
94 return -EBUSY;
95
96 data = hdev->driver_data;
97
98 memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
99 skb_queue_tail(&data->readq, skb);
100
101 wake_up_interruptible(&data->read_wait);
102
103 return 0;
104 }
105
vhci_destruct(struct hci_dev * hdev)106 static void vhci_destruct(struct hci_dev *hdev)
107 {
108 kfree(hdev->driver_data);
109 }
110
vhci_get_user(struct vhci_data * data,const char __user * buf,size_t count)111 static inline ssize_t vhci_get_user(struct vhci_data *data,
112 const char __user *buf, size_t count)
113 {
114 struct sk_buff *skb;
115
116 if (count > HCI_MAX_FRAME_SIZE)
117 return -EINVAL;
118
119 skb = bt_skb_alloc(count, GFP_KERNEL);
120 if (!skb)
121 return -ENOMEM;
122
123 if (copy_from_user(skb_put(skb, count), buf, count)) {
124 kfree_skb(skb);
125 return -EFAULT;
126 }
127
128 skb->dev = (void *) data->hdev;
129 bt_cb(skb)->pkt_type = *((__u8 *) skb->data);
130 skb_pull(skb, 1);
131
132 hci_recv_frame(skb);
133
134 return count;
135 }
136
vhci_put_user(struct vhci_data * data,struct sk_buff * skb,char __user * buf,int count)137 static inline ssize_t vhci_put_user(struct vhci_data *data,
138 struct sk_buff *skb, char __user *buf, int count)
139 {
140 char __user *ptr = buf;
141 int len, total = 0;
142
143 len = min_t(unsigned int, skb->len, count);
144
145 if (copy_to_user(ptr, skb->data, len))
146 return -EFAULT;
147
148 total += len;
149
150 data->hdev->stat.byte_tx += len;
151
152 switch (bt_cb(skb)->pkt_type) {
153 case HCI_COMMAND_PKT:
154 data->hdev->stat.cmd_tx++;
155 break;
156
157 case HCI_ACLDATA_PKT:
158 data->hdev->stat.acl_tx++;
159 break;
160
161 case HCI_SCODATA_PKT:
162 data->hdev->stat.sco_tx++;
163 break;
164 };
165
166 return total;
167 }
168
vhci_read(struct file * file,char __user * buf,size_t count,loff_t * pos)169 static ssize_t vhci_read(struct file *file,
170 char __user *buf, size_t count, loff_t *pos)
171 {
172 struct vhci_data *data = file->private_data;
173 struct sk_buff *skb;
174 ssize_t ret = 0;
175
176 while (count) {
177 skb = skb_dequeue(&data->readq);
178 if (skb) {
179 ret = vhci_put_user(data, skb, buf, count);
180 if (ret < 0)
181 skb_queue_head(&data->readq, skb);
182 else
183 kfree_skb(skb);
184 break;
185 }
186
187 if (file->f_flags & O_NONBLOCK) {
188 ret = -EAGAIN;
189 break;
190 }
191
192 ret = wait_event_interruptible(data->read_wait,
193 !skb_queue_empty(&data->readq));
194 if (ret < 0)
195 break;
196 }
197
198 return ret;
199 }
200
vhci_write(struct file * file,const char __user * buf,size_t count,loff_t * pos)201 static ssize_t vhci_write(struct file *file,
202 const char __user *buf, size_t count, loff_t *pos)
203 {
204 struct vhci_data *data = file->private_data;
205
206 return vhci_get_user(data, buf, count);
207 }
208
vhci_poll(struct file * file,poll_table * wait)209 static unsigned int vhci_poll(struct file *file, poll_table *wait)
210 {
211 struct vhci_data *data = file->private_data;
212
213 poll_wait(file, &data->read_wait, wait);
214
215 if (!skb_queue_empty(&data->readq))
216 return POLLIN | POLLRDNORM;
217
218 return POLLOUT | POLLWRNORM;
219 }
220
vhci_open(struct inode * inode,struct file * file)221 static int vhci_open(struct inode *inode, struct file *file)
222 {
223 struct vhci_data *data;
224 struct hci_dev *hdev;
225
226 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
227 if (!data)
228 return -ENOMEM;
229
230 skb_queue_head_init(&data->readq);
231 init_waitqueue_head(&data->read_wait);
232
233 hdev = hci_alloc_dev();
234 if (!hdev) {
235 kfree(data);
236 return -ENOMEM;
237 }
238
239 data->hdev = hdev;
240
241 hdev->bus = HCI_VIRTUAL;
242 hdev->driver_data = data;
243
244 if (amp)
245 hdev->dev_type = HCI_AMP;
246
247 hdev->open = vhci_open_dev;
248 hdev->close = vhci_close_dev;
249 hdev->flush = vhci_flush;
250 hdev->send = vhci_send_frame;
251 hdev->destruct = vhci_destruct;
252
253 hdev->owner = THIS_MODULE;
254
255 if (hci_register_dev(hdev) < 0) {
256 BT_ERR("Can't register HCI device");
257 kfree(data);
258 hci_free_dev(hdev);
259 return -EBUSY;
260 }
261
262 file->private_data = data;
263
264 return nonseekable_open(inode, file);
265 }
266
vhci_release(struct inode * inode,struct file * file)267 static int vhci_release(struct inode *inode, struct file *file)
268 {
269 struct vhci_data *data = file->private_data;
270 struct hci_dev *hdev = data->hdev;
271
272 hci_unregister_dev(hdev);
273 hci_free_dev(hdev);
274
275 file->private_data = NULL;
276
277 return 0;
278 }
279
280 static const struct file_operations vhci_fops = {
281 .owner = THIS_MODULE,
282 .read = vhci_read,
283 .write = vhci_write,
284 .poll = vhci_poll,
285 .open = vhci_open,
286 .release = vhci_release,
287 .llseek = no_llseek,
288 };
289
290 static struct miscdevice vhci_miscdev= {
291 .name = "vhci",
292 .fops = &vhci_fops,
293 .minor = MISC_DYNAMIC_MINOR,
294 };
295
vhci_init(void)296 static int __init vhci_init(void)
297 {
298 BT_INFO("Virtual HCI driver ver %s", VERSION);
299
300 return misc_register(&vhci_miscdev);
301 }
302
vhci_exit(void)303 static void __exit vhci_exit(void)
304 {
305 misc_deregister(&vhci_miscdev);
306 }
307
308 module_init(vhci_init);
309 module_exit(vhci_exit);
310
311 module_param(amp, bool, 0644);
312 MODULE_PARM_DESC(amp, "Create AMP controller device");
313
314 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
315 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
316 MODULE_VERSION(VERSION);
317 MODULE_LICENSE("GPL");
318