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 "1.5" 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 opcode) 99 { 100 struct hci_dev *hdev; 101 struct sk_buff *skb; 102 __u8 dev_type; 103 104 /* bits 0-1 are dev_type (BR/EDR or AMP) */ 105 dev_type = opcode & 0x03; 106 107 if (dev_type != HCI_BREDR && dev_type != HCI_AMP) 108 return -EINVAL; 109 110 /* bits 2-5 are reserved (must be zero) */ 111 if (opcode & 0x3c) 112 return -EINVAL; 113 114 skb = bt_skb_alloc(4, GFP_KERNEL); 115 if (!skb) 116 return -ENOMEM; 117 118 hdev = hci_alloc_dev(); 119 if (!hdev) { 120 kfree_skb(skb); 121 return -ENOMEM; 122 } 123 124 data->hdev = hdev; 125 126 hdev->bus = HCI_VIRTUAL; 127 hdev->dev_type = dev_type; 128 hci_set_drvdata(hdev, data); 129 130 hdev->open = vhci_open_dev; 131 hdev->close = vhci_close_dev; 132 hdev->flush = vhci_flush; 133 hdev->send = vhci_send_frame; 134 135 /* bit 6 is for external configuration */ 136 if (opcode & 0x40) 137 set_bit(HCI_QUIRK_EXTERNAL_CONFIG, &hdev->quirks); 138 139 /* bit 7 is for raw device */ 140 if (opcode & 0x80) 141 set_bit(HCI_QUIRK_RAW_DEVICE, &hdev->quirks); 142 143 if (hci_register_dev(hdev) < 0) { 144 BT_ERR("Can't register HCI device"); 145 hci_free_dev(hdev); 146 data->hdev = NULL; 147 kfree_skb(skb); 148 return -EBUSY; 149 } 150 151 bt_cb(skb)->pkt_type = HCI_VENDOR_PKT; 152 153 *skb_put(skb, 1) = 0xff; 154 *skb_put(skb, 1) = opcode; 155 put_unaligned_le16(hdev->id, skb_put(skb, 2)); 156 skb_queue_tail(&data->readq, skb); 157 158 wake_up_interruptible(&data->read_wait); 159 return 0; 160 } 161 162 static inline ssize_t vhci_get_user(struct vhci_data *data, 163 const struct iovec *iov, 164 unsigned long count) 165 { 166 size_t len = iov_length(iov, count); 167 struct sk_buff *skb; 168 __u8 pkt_type, opcode; 169 unsigned long i; 170 int ret; 171 172 if (len < 2 || len > HCI_MAX_FRAME_SIZE) 173 return -EINVAL; 174 175 skb = bt_skb_alloc(len, GFP_KERNEL); 176 if (!skb) 177 return -ENOMEM; 178 179 for (i = 0; i < count; i++) { 180 if (copy_from_user(skb_put(skb, iov[i].iov_len), 181 iov[i].iov_base, iov[i].iov_len)) { 182 kfree_skb(skb); 183 return -EFAULT; 184 } 185 } 186 187 pkt_type = *((__u8 *) skb->data); 188 skb_pull(skb, 1); 189 190 switch (pkt_type) { 191 case HCI_EVENT_PKT: 192 case HCI_ACLDATA_PKT: 193 case HCI_SCODATA_PKT: 194 if (!data->hdev) { 195 kfree_skb(skb); 196 return -ENODEV; 197 } 198 199 bt_cb(skb)->pkt_type = pkt_type; 200 201 ret = hci_recv_frame(data->hdev, skb); 202 break; 203 204 case HCI_VENDOR_PKT: 205 if (data->hdev) { 206 kfree_skb(skb); 207 return -EBADFD; 208 } 209 210 cancel_delayed_work_sync(&data->open_timeout); 211 212 opcode = *((__u8 *) skb->data); 213 skb_pull(skb, 1); 214 215 if (skb->len > 0) { 216 kfree_skb(skb); 217 return -EINVAL; 218 } 219 220 kfree_skb(skb); 221 222 ret = vhci_create_device(data, opcode); 223 break; 224 225 default: 226 kfree_skb(skb); 227 return -EINVAL; 228 } 229 230 return (ret < 0) ? ret : len; 231 } 232 233 static inline ssize_t vhci_put_user(struct vhci_data *data, 234 struct sk_buff *skb, 235 char __user *buf, int count) 236 { 237 char __user *ptr = buf; 238 int len; 239 240 len = min_t(unsigned int, skb->len, count); 241 242 if (copy_to_user(ptr, skb->data, len)) 243 return -EFAULT; 244 245 if (!data->hdev) 246 return len; 247 248 data->hdev->stat.byte_tx += len; 249 250 switch (bt_cb(skb)->pkt_type) { 251 case HCI_COMMAND_PKT: 252 data->hdev->stat.cmd_tx++; 253 break; 254 case HCI_ACLDATA_PKT: 255 data->hdev->stat.acl_tx++; 256 break; 257 case HCI_SCODATA_PKT: 258 data->hdev->stat.sco_tx++; 259 break; 260 } 261 262 return len; 263 } 264 265 static ssize_t vhci_read(struct file *file, 266 char __user *buf, size_t count, loff_t *pos) 267 { 268 struct vhci_data *data = file->private_data; 269 struct sk_buff *skb; 270 ssize_t ret = 0; 271 272 while (count) { 273 skb = skb_dequeue(&data->readq); 274 if (skb) { 275 ret = vhci_put_user(data, skb, buf, count); 276 if (ret < 0) 277 skb_queue_head(&data->readq, skb); 278 else 279 kfree_skb(skb); 280 break; 281 } 282 283 if (file->f_flags & O_NONBLOCK) { 284 ret = -EAGAIN; 285 break; 286 } 287 288 ret = wait_event_interruptible(data->read_wait, 289 !skb_queue_empty(&data->readq)); 290 if (ret < 0) 291 break; 292 } 293 294 return ret; 295 } 296 297 static ssize_t vhci_write(struct kiocb *iocb, const struct iovec *iov, 298 unsigned long count, loff_t pos) 299 { 300 struct file *file = iocb->ki_filp; 301 struct vhci_data *data = file->private_data; 302 303 return vhci_get_user(data, iov, count); 304 } 305 306 static unsigned int vhci_poll(struct file *file, poll_table *wait) 307 { 308 struct vhci_data *data = file->private_data; 309 310 poll_wait(file, &data->read_wait, wait); 311 312 if (!skb_queue_empty(&data->readq)) 313 return POLLIN | POLLRDNORM; 314 315 return POLLOUT | POLLWRNORM; 316 } 317 318 static void vhci_open_timeout(struct work_struct *work) 319 { 320 struct vhci_data *data = container_of(work, struct vhci_data, 321 open_timeout.work); 322 323 vhci_create_device(data, amp ? HCI_AMP : HCI_BREDR); 324 } 325 326 static int vhci_open(struct inode *inode, struct file *file) 327 { 328 struct vhci_data *data; 329 330 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL); 331 if (!data) 332 return -ENOMEM; 333 334 skb_queue_head_init(&data->readq); 335 init_waitqueue_head(&data->read_wait); 336 337 INIT_DELAYED_WORK(&data->open_timeout, vhci_open_timeout); 338 339 file->private_data = data; 340 nonseekable_open(inode, file); 341 342 schedule_delayed_work(&data->open_timeout, msecs_to_jiffies(1000)); 343 344 return 0; 345 } 346 347 static int vhci_release(struct inode *inode, struct file *file) 348 { 349 struct vhci_data *data = file->private_data; 350 struct hci_dev *hdev = data->hdev; 351 352 cancel_delayed_work_sync(&data->open_timeout); 353 354 if (hdev) { 355 hci_unregister_dev(hdev); 356 hci_free_dev(hdev); 357 } 358 359 file->private_data = NULL; 360 kfree(data); 361 362 return 0; 363 } 364 365 static const struct file_operations vhci_fops = { 366 .owner = THIS_MODULE, 367 .read = vhci_read, 368 .aio_write = vhci_write, 369 .poll = vhci_poll, 370 .open = vhci_open, 371 .release = vhci_release, 372 .llseek = no_llseek, 373 }; 374 375 static struct miscdevice vhci_miscdev= { 376 .name = "vhci", 377 .fops = &vhci_fops, 378 .minor = VHCI_MINOR, 379 }; 380 381 static int __init vhci_init(void) 382 { 383 BT_INFO("Virtual HCI driver ver %s", VERSION); 384 385 return misc_register(&vhci_miscdev); 386 } 387 388 static void __exit vhci_exit(void) 389 { 390 misc_deregister(&vhci_miscdev); 391 } 392 393 module_init(vhci_init); 394 module_exit(vhci_exit); 395 396 module_param(amp, bool, 0644); 397 MODULE_PARM_DESC(amp, "Create AMP controller device"); 398 399 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 400 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); 401 MODULE_VERSION(VERSION); 402 MODULE_LICENSE("GPL"); 403 MODULE_ALIAS("devname:vhci"); 404 MODULE_ALIAS_MISCDEV(VHCI_MINOR); 405