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 bool amp; 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 = hci_get_drvdata(hdev); 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 = hci_get_drvdata(hdev); 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 = hci_get_drvdata(hdev); 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 inline ssize_t vhci_get_user(struct vhci_data *data, 107 const char __user *buf, size_t count) 108 { 109 struct sk_buff *skb; 110 111 if (count > HCI_MAX_FRAME_SIZE) 112 return -EINVAL; 113 114 skb = bt_skb_alloc(count, GFP_KERNEL); 115 if (!skb) 116 return -ENOMEM; 117 118 if (copy_from_user(skb_put(skb, count), buf, count)) { 119 kfree_skb(skb); 120 return -EFAULT; 121 } 122 123 skb->dev = (void *) data->hdev; 124 bt_cb(skb)->pkt_type = *((__u8 *) skb->data); 125 skb_pull(skb, 1); 126 127 hci_recv_frame(skb); 128 129 return count; 130 } 131 132 static inline ssize_t vhci_put_user(struct vhci_data *data, 133 struct sk_buff *skb, char __user *buf, int count) 134 { 135 char __user *ptr = buf; 136 int len, total = 0; 137 138 len = min_t(unsigned int, skb->len, count); 139 140 if (copy_to_user(ptr, skb->data, len)) 141 return -EFAULT; 142 143 total += len; 144 145 data->hdev->stat.byte_tx += len; 146 147 switch (bt_cb(skb)->pkt_type) { 148 case HCI_COMMAND_PKT: 149 data->hdev->stat.cmd_tx++; 150 break; 151 152 case HCI_ACLDATA_PKT: 153 data->hdev->stat.acl_tx++; 154 break; 155 156 case HCI_SCODATA_PKT: 157 data->hdev->stat.sco_tx++; 158 break; 159 } 160 161 return total; 162 } 163 164 static ssize_t vhci_read(struct file *file, 165 char __user *buf, size_t count, loff_t *pos) 166 { 167 struct vhci_data *data = file->private_data; 168 struct sk_buff *skb; 169 ssize_t ret = 0; 170 171 while (count) { 172 skb = skb_dequeue(&data->readq); 173 if (skb) { 174 ret = vhci_put_user(data, skb, buf, count); 175 if (ret < 0) 176 skb_queue_head(&data->readq, skb); 177 else 178 kfree_skb(skb); 179 break; 180 } 181 182 if (file->f_flags & O_NONBLOCK) { 183 ret = -EAGAIN; 184 break; 185 } 186 187 ret = wait_event_interruptible(data->read_wait, 188 !skb_queue_empty(&data->readq)); 189 if (ret < 0) 190 break; 191 } 192 193 return ret; 194 } 195 196 static ssize_t vhci_write(struct file *file, 197 const char __user *buf, size_t count, loff_t *pos) 198 { 199 struct vhci_data *data = file->private_data; 200 201 return vhci_get_user(data, buf, count); 202 } 203 204 static unsigned int vhci_poll(struct file *file, poll_table *wait) 205 { 206 struct vhci_data *data = file->private_data; 207 208 poll_wait(file, &data->read_wait, wait); 209 210 if (!skb_queue_empty(&data->readq)) 211 return POLLIN | POLLRDNORM; 212 213 return POLLOUT | POLLWRNORM; 214 } 215 216 static int vhci_open(struct inode *inode, struct file *file) 217 { 218 struct vhci_data *data; 219 struct hci_dev *hdev; 220 221 data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL); 222 if (!data) 223 return -ENOMEM; 224 225 skb_queue_head_init(&data->readq); 226 init_waitqueue_head(&data->read_wait); 227 228 hdev = hci_alloc_dev(); 229 if (!hdev) { 230 kfree(data); 231 return -ENOMEM; 232 } 233 234 data->hdev = hdev; 235 236 hdev->bus = HCI_VIRTUAL; 237 hci_set_drvdata(hdev, data); 238 239 if (amp) 240 hdev->dev_type = HCI_AMP; 241 242 hdev->open = vhci_open_dev; 243 hdev->close = vhci_close_dev; 244 hdev->flush = vhci_flush; 245 hdev->send = vhci_send_frame; 246 247 if (hci_register_dev(hdev) < 0) { 248 BT_ERR("Can't register HCI device"); 249 kfree(data); 250 hci_free_dev(hdev); 251 return -EBUSY; 252 } 253 254 file->private_data = data; 255 nonseekable_open(inode, file); 256 257 return 0; 258 } 259 260 static int vhci_release(struct inode *inode, struct file *file) 261 { 262 struct vhci_data *data = file->private_data; 263 struct hci_dev *hdev = data->hdev; 264 265 hci_unregister_dev(hdev); 266 hci_free_dev(hdev); 267 268 file->private_data = NULL; 269 kfree(data); 270 271 return 0; 272 } 273 274 static const struct file_operations vhci_fops = { 275 .owner = THIS_MODULE, 276 .read = vhci_read, 277 .write = vhci_write, 278 .poll = vhci_poll, 279 .open = vhci_open, 280 .release = vhci_release, 281 .llseek = no_llseek, 282 }; 283 284 static struct miscdevice vhci_miscdev= { 285 .name = "vhci", 286 .fops = &vhci_fops, 287 .minor = MISC_DYNAMIC_MINOR, 288 }; 289 290 static int __init vhci_init(void) 291 { 292 BT_INFO("Virtual HCI driver ver %s", VERSION); 293 294 return misc_register(&vhci_miscdev); 295 } 296 297 static void __exit vhci_exit(void) 298 { 299 misc_deregister(&vhci_miscdev); 300 } 301 302 module_init(vhci_init); 303 module_exit(vhci_exit); 304 305 module_param(amp, bool, 0644); 306 MODULE_PARM_DESC(amp, "Create AMP controller device"); 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