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 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 } 216 217 static 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 } 248 249 static 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 } 280 281 static 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 } 289 290 static 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 } 301 302 static 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 } 309 310 static 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 } 330 331 static 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 } 348 349 static 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 }; 358 359 static struct miscdevice vhci_miscdev= { 360 .name = "vhci", 361 .fops = &vhci_fops, 362 .minor = MISC_DYNAMIC_MINOR, 363 }; 364 365 static int __init vhci_init(void) 366 { 367 BT_INFO("Virtual HCI driver ver %s", VERSION); 368 369 return misc_register(&vhci_miscdev); 370 } 371 372 static void __exit vhci_exit(void) 373 { 374 misc_deregister(&vhci_miscdev); 375 } 376 377 module_init(vhci_init); 378 module_exit(vhci_exit); 379 380 module_param(amp, bool, 0644); 381 MODULE_PARM_DESC(amp, "Create AMP controller device"); 382 383 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 384 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); 385 MODULE_VERSION(VERSION); 386 MODULE_LICENSE("GPL"); 387 MODULE_ALIAS("devname:vhci"); 388