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 45 static bool amp; 46 47 struct 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 56 static int vhci_open_dev(struct hci_dev *hdev) 57 { 58 set_bit(HCI_RUNNING, &hdev->flags); 59 60 return 0; 61 } 62 63 static 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 75 static 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 84 static 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 98 static 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 } 142 143 static inline ssize_t vhci_get_user(struct vhci_data *data, 144 const char __user *buf, size_t count) 145 { 146 struct sk_buff *skb; 147 __u8 pkt_type, dev_type; 148 int ret; 149 150 if (count < 2 || count > HCI_MAX_FRAME_SIZE) 151 return -EINVAL; 152 153 skb = bt_skb_alloc(count, GFP_KERNEL); 154 if (!skb) 155 return -ENOMEM; 156 157 if (copy_from_user(skb_put(skb, count), buf, count)) { 158 kfree_skb(skb); 159 return -EFAULT; 160 } 161 162 pkt_type = *((__u8 *) skb->data); 163 skb_pull(skb, 1); 164 165 switch (pkt_type) { 166 case HCI_EVENT_PKT: 167 case HCI_ACLDATA_PKT: 168 case HCI_SCODATA_PKT: 169 if (!data->hdev) { 170 kfree_skb(skb); 171 return -ENODEV; 172 } 173 174 bt_cb(skb)->pkt_type = pkt_type; 175 176 ret = hci_recv_frame(data->hdev, skb); 177 break; 178 179 case HCI_VENDOR_PKT: 180 if (data->hdev) { 181 kfree_skb(skb); 182 return -EBADFD; 183 } 184 185 cancel_delayed_work_sync(&data->open_timeout); 186 187 dev_type = *((__u8 *) skb->data); 188 skb_pull(skb, 1); 189 190 if (skb->len > 0) { 191 kfree_skb(skb); 192 return -EINVAL; 193 } 194 195 kfree_skb(skb); 196 197 if (dev_type != HCI_BREDR && dev_type != HCI_AMP) 198 return -EINVAL; 199 200 ret = vhci_create_device(data, dev_type); 201 break; 202 203 default: 204 kfree_skb(skb); 205 return -EINVAL; 206 } 207 208 return (ret < 0) ? ret : count; 209 } 210 211 static inline ssize_t vhci_put_user(struct vhci_data *data, 212 struct sk_buff *skb, 213 char __user *buf, int count) 214 { 215 char __user *ptr = buf; 216 int len; 217 218 len = min_t(unsigned int, skb->len, count); 219 220 if (copy_to_user(ptr, skb->data, len)) 221 return -EFAULT; 222 223 if (!data->hdev) 224 return len; 225 226 data->hdev->stat.byte_tx += len; 227 228 switch (bt_cb(skb)->pkt_type) { 229 case HCI_COMMAND_PKT: 230 data->hdev->stat.cmd_tx++; 231 break; 232 case HCI_ACLDATA_PKT: 233 data->hdev->stat.acl_tx++; 234 break; 235 case HCI_SCODATA_PKT: 236 data->hdev->stat.sco_tx++; 237 break; 238 } 239 240 return len; 241 } 242 243 static ssize_t vhci_read(struct file *file, 244 char __user *buf, size_t count, loff_t *pos) 245 { 246 struct vhci_data *data = file->private_data; 247 struct sk_buff *skb; 248 ssize_t ret = 0; 249 250 while (count) { 251 skb = skb_dequeue(&data->readq); 252 if (skb) { 253 ret = vhci_put_user(data, skb, buf, count); 254 if (ret < 0) 255 skb_queue_head(&data->readq, skb); 256 else 257 kfree_skb(skb); 258 break; 259 } 260 261 if (file->f_flags & O_NONBLOCK) { 262 ret = -EAGAIN; 263 break; 264 } 265 266 ret = wait_event_interruptible(data->read_wait, 267 !skb_queue_empty(&data->readq)); 268 if (ret < 0) 269 break; 270 } 271 272 return ret; 273 } 274 275 static ssize_t vhci_write(struct file *file, 276 const char __user *buf, size_t count, loff_t *pos) 277 { 278 struct vhci_data *data = file->private_data; 279 280 return vhci_get_user(data, buf, count); 281 } 282 283 static unsigned int vhci_poll(struct file *file, poll_table *wait) 284 { 285 struct vhci_data *data = file->private_data; 286 287 poll_wait(file, &data->read_wait, wait); 288 289 if (!skb_queue_empty(&data->readq)) 290 return POLLIN | POLLRDNORM; 291 292 return POLLOUT | POLLWRNORM; 293 } 294 295 static void vhci_open_timeout(struct work_struct *work) 296 { 297 struct vhci_data *data = container_of(work, struct vhci_data, 298 open_timeout.work); 299 300 vhci_create_device(data, amp ? HCI_AMP : HCI_BREDR); 301 } 302 303 static int vhci_open(struct inode *inode, struct file *file) 304 { 305 struct vhci_data *data; 306 307 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL); 308 if (!data) 309 return -ENOMEM; 310 311 skb_queue_head_init(&data->readq); 312 init_waitqueue_head(&data->read_wait); 313 314 INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout); 315 316 file->private_data = data; 317 nonseekable_open(inode, file); 318 319 schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000)); 320 321 return 0; 322 } 323 324 static int vhci_release(struct inode *inode, struct file *file) 325 { 326 struct vhci_data *data = file->private_data; 327 struct hci_dev *hdev = data->hdev; 328 329 cancel_delayed_work_sync(&data->open_timeout); 330 331 if (hdev) { 332 hci_unregister_dev(hdev); 333 hci_free_dev(hdev); 334 } 335 336 file->private_data = NULL; 337 kfree(data); 338 339 return 0; 340 } 341 342 static const struct file_operations vhci_fops = { 343 .owner = THIS_MODULE, 344 .read = vhci_read, 345 .write = vhci_write, 346 .poll = vhci_poll, 347 .open = vhci_open, 348 .release = vhci_release, 349 .llseek = no_llseek, 350 }; 351 352 static struct miscdevice vhci_miscdev= { 353 .name = "vhci", 354 .fops = &vhci_fops, 355 .minor = MISC_DYNAMIC_MINOR, 356 }; 357 358 static int __init vhci_init(void) 359 { 360 BT_INFO("Virtual HCI driver ver %s", VERSION); 361 362 return misc_register(&vhci_miscdev); 363 } 364 365 static void __exit vhci_exit(void) 366 { 367 misc_deregister(&vhci_miscdev); 368 } 369 370 module_init(vhci_init); 371 module_exit(vhci_exit); 372 373 module_param(amp, bool, 0644); 374 MODULE_PARM_DESC(amp, "Create AMP controller device"); 375 376 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 377 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); 378 MODULE_VERSION(VERSION); 379 MODULE_LICENSE("GPL"); 380 MODULE_ALIAS("devname:vhci"); 381