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 int minor = MISC_DYNAMIC_MINOR; 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 55 static int vhci_open_dev(struct hci_dev *hdev) 56 { 57 set_bit(HCI_RUNNING, &hdev->flags); 58 59 return 0; 60 } 61 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 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 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 } 105 106 static void vhci_destruct(struct hci_dev *hdev) 107 { 108 kfree(hdev->driver_data); 109 } 110 111 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 } 136 137 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.cmd_tx++; 163 break; 164 }; 165 166 return total; 167 } 168 169 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 } 200 201 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 } 208 209 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 } 220 221 static int vhci_ioctl(struct inode *inode, struct file *file, 222 unsigned int cmd, unsigned long arg) 223 { 224 return -EINVAL; 225 } 226 227 static int vhci_open(struct inode *inode, struct file *file) 228 { 229 struct vhci_data *data; 230 struct hci_dev *hdev; 231 232 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL); 233 if (!data) 234 return -ENOMEM; 235 236 skb_queue_head_init(&data->readq); 237 init_waitqueue_head(&data->read_wait); 238 239 hdev = hci_alloc_dev(); 240 if (!hdev) { 241 kfree(data); 242 return -ENOMEM; 243 } 244 245 data->hdev = hdev; 246 247 hdev->type = HCI_VIRTUAL; 248 hdev->driver_data = data; 249 250 hdev->open = vhci_open_dev; 251 hdev->close = vhci_close_dev; 252 hdev->flush = vhci_flush; 253 hdev->send = vhci_send_frame; 254 hdev->destruct = vhci_destruct; 255 256 hdev->owner = THIS_MODULE; 257 258 if (hci_register_dev(hdev) < 0) { 259 BT_ERR("Can't register HCI device"); 260 kfree(data); 261 hci_free_dev(hdev); 262 return -EBUSY; 263 } 264 265 file->private_data = data; 266 267 return nonseekable_open(inode, file); 268 } 269 270 static int vhci_release(struct inode *inode, struct file *file) 271 { 272 struct vhci_data *data = file->private_data; 273 struct hci_dev *hdev = data->hdev; 274 275 if (hci_unregister_dev(hdev) < 0) { 276 BT_ERR("Can't unregister HCI device %s", hdev->name); 277 } 278 279 hci_free_dev(hdev); 280 281 file->private_data = NULL; 282 283 return 0; 284 } 285 286 static const struct file_operations vhci_fops = { 287 .read = vhci_read, 288 .write = vhci_write, 289 .poll = vhci_poll, 290 .ioctl = vhci_ioctl, 291 .open = vhci_open, 292 .release = vhci_release, 293 }; 294 295 static struct miscdevice vhci_miscdev= { 296 .name = "vhci", 297 .fops = &vhci_fops, 298 .minor = MISC_DYNAMIC_MINOR, 299 }; 300 301 static int __init vhci_init(void) 302 { 303 BT_INFO("Virtual HCI driver ver %s", VERSION); 304 305 if (misc_register(&vhci_miscdev) < 0) { 306 BT_ERR("Can't register misc device with minor %d", minor); 307 return -EIO; 308 } 309 310 return 0; 311 } 312 313 static void __exit vhci_exit(void) 314 { 315 if (misc_deregister(&vhci_miscdev) < 0) 316 BT_ERR("Can't unregister misc device with minor %d", minor); 317 } 318 319 module_init(vhci_init); 320 module_exit(vhci_exit); 321 322 MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>"); 323 MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION); 324 MODULE_VERSION(VERSION); 325 MODULE_LICENSE("GPL"); 326