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