linux/drivers/bluetooth/hci_vhci.c
Jonathan Corbet dbfb2df7e9 Bluetooth VHCI: fasync BKL pushdown
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2008-07-02 15:06:28 -06:00

383 lines
7.7 KiB
C

/*
*
* Bluetooth virtual HCI driver
*
* Copyright (C) 2000-2001 Qualcomm Incorporated
* Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
* Copyright (C) 2004-2006 Marcel Holtmann <marcel@holtmann.org>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/poll.h>
#include <linux/skbuff.h>
#include <linux/miscdevice.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
#ifndef CONFIG_BT_HCIVHCI_DEBUG
#undef BT_DBG
#define BT_DBG(D...)
#endif
#define VERSION "1.2"
static int minor = MISC_DYNAMIC_MINOR;
struct vhci_data {
struct hci_dev *hdev;
unsigned long flags;
wait_queue_head_t read_wait;
struct sk_buff_head readq;
struct fasync_struct *fasync;
};
#define VHCI_FASYNC 0x0010
static struct miscdevice vhci_miscdev;
static int vhci_open_dev(struct hci_dev *hdev)
{
set_bit(HCI_RUNNING, &hdev->flags);
return 0;
}
static int vhci_close_dev(struct hci_dev *hdev)
{
struct vhci_data *data = hdev->driver_data;
if (!test_and_clear_bit(HCI_RUNNING, &hdev->flags))
return 0;
skb_queue_purge(&data->readq);
return 0;
}
static int vhci_flush(struct hci_dev *hdev)
{
struct vhci_data *data = hdev->driver_data;
skb_queue_purge(&data->readq);
return 0;
}
static int vhci_send_frame(struct sk_buff *skb)
{
struct hci_dev* hdev = (struct hci_dev *) skb->dev;
struct vhci_data *data;
if (!hdev) {
BT_ERR("Frame for unknown HCI device (hdev=NULL)");
return -ENODEV;
}
if (!test_bit(HCI_RUNNING, &hdev->flags))
return -EBUSY;
data = hdev->driver_data;
memcpy(skb_push(skb, 1), &bt_cb(skb)->pkt_type, 1);
skb_queue_tail(&data->readq, skb);
if (data->flags & VHCI_FASYNC)
kill_fasync(&data->fasync, SIGIO, POLL_IN);
wake_up_interruptible(&data->read_wait);
return 0;
}
static void vhci_destruct(struct hci_dev *hdev)
{
kfree(hdev->driver_data);
}
static inline ssize_t vhci_get_user(struct vhci_data *data,
const char __user *buf, size_t count)
{
struct sk_buff *skb;
if (count > HCI_MAX_FRAME_SIZE)
return -EINVAL;
skb = bt_skb_alloc(count, GFP_KERNEL);
if (!skb)
return -ENOMEM;
if (copy_from_user(skb_put(skb, count), buf, count)) {
kfree_skb(skb);
return -EFAULT;
}
skb->dev = (void *) data->hdev;
bt_cb(skb)->pkt_type = *((__u8 *) skb->data);
skb_pull(skb, 1);
hci_recv_frame(skb);
return count;
}
static inline ssize_t vhci_put_user(struct vhci_data *data,
struct sk_buff *skb, char __user *buf, int count)
{
char __user *ptr = buf;
int len, total = 0;
len = min_t(unsigned int, skb->len, count);
if (copy_to_user(ptr, skb->data, len))
return -EFAULT;
total += len;
data->hdev->stat.byte_tx += len;
switch (bt_cb(skb)->pkt_type) {
case HCI_COMMAND_PKT:
data->hdev->stat.cmd_tx++;
break;
case HCI_ACLDATA_PKT:
data->hdev->stat.acl_tx++;
break;
case HCI_SCODATA_PKT:
data->hdev->stat.cmd_tx++;
break;
};
return total;
}
static ssize_t vhci_read(struct file *file,
char __user *buf, size_t count, loff_t *pos)
{
DECLARE_WAITQUEUE(wait, current);
struct vhci_data *data = file->private_data;
struct sk_buff *skb;
ssize_t ret = 0;
add_wait_queue(&data->read_wait, &wait);
while (count) {
set_current_state(TASK_INTERRUPTIBLE);
skb = skb_dequeue(&data->readq);
if (!skb) {
if (file->f_flags & O_NONBLOCK) {
ret = -EAGAIN;
break;
}
if (signal_pending(current)) {
ret = -ERESTARTSYS;
break;
}
schedule();
continue;
}
if (access_ok(VERIFY_WRITE, buf, count))
ret = vhci_put_user(data, skb, buf, count);
else
ret = -EFAULT;
kfree_skb(skb);
break;
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&data->read_wait, &wait);
return ret;
}
static ssize_t vhci_write(struct file *file,
const char __user *buf, size_t count, loff_t *pos)
{
struct vhci_data *data = file->private_data;
if (!access_ok(VERIFY_READ, buf, count))
return -EFAULT;
return vhci_get_user(data, buf, count);
}
static unsigned int vhci_poll(struct file *file, poll_table *wait)
{
struct vhci_data *data = file->private_data;
poll_wait(file, &data->read_wait, wait);
if (!skb_queue_empty(&data->readq))
return POLLIN | POLLRDNORM;
return POLLOUT | POLLWRNORM;
}
static int vhci_ioctl(struct inode *inode, struct file *file,
unsigned int cmd, unsigned long arg)
{
return -EINVAL;
}
static int vhci_open(struct inode *inode, struct file *file)
{
struct vhci_data *data;
struct hci_dev *hdev;
data = kzalloc(sizeof(struct vhci_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
skb_queue_head_init(&data->readq);
init_waitqueue_head(&data->read_wait);
lock_kernel();
hdev = hci_alloc_dev();
if (!hdev) {
kfree(data);
unlock_kernel();
return -ENOMEM;
}
data->hdev = hdev;
hdev->type = HCI_VIRTUAL;
hdev->driver_data = data;
hdev->open = vhci_open_dev;
hdev->close = vhci_close_dev;
hdev->flush = vhci_flush;
hdev->send = vhci_send_frame;
hdev->destruct = vhci_destruct;
hdev->owner = THIS_MODULE;
if (hci_register_dev(hdev) < 0) {
BT_ERR("Can't register HCI device");
kfree(data);
hci_free_dev(hdev);
unlock_kernel();
return -EBUSY;
}
file->private_data = data;
unlock_kernel();
return nonseekable_open(inode, file);
}
static int vhci_release(struct inode *inode, struct file *file)
{
struct vhci_data *data = file->private_data;
struct hci_dev *hdev = data->hdev;
if (hci_unregister_dev(hdev) < 0) {
BT_ERR("Can't unregister HCI device %s", hdev->name);
}
hci_free_dev(hdev);
file->private_data = NULL;
return 0;
}
static int vhci_fasync(int fd, struct file *file, int on)
{
struct vhci_data *data = file->private_data;
int err = 0;
lock_kernel();
err = fasync_helper(fd, file, on, &data->fasync);
if (err < 0)
goto out;
if (on)
data->flags |= VHCI_FASYNC;
else
data->flags &= ~VHCI_FASYNC;
out:
unlock_kernel();
return err;
}
static const struct file_operations vhci_fops = {
.owner = THIS_MODULE,
.read = vhci_read,
.write = vhci_write,
.poll = vhci_poll,
.ioctl = vhci_ioctl,
.open = vhci_open,
.release = vhci_release,
.fasync = vhci_fasync,
};
static struct miscdevice vhci_miscdev= {
.name = "vhci",
.fops = &vhci_fops,
};
static int __init vhci_init(void)
{
BT_INFO("Virtual HCI driver ver %s", VERSION);
vhci_miscdev.minor = minor;
if (misc_register(&vhci_miscdev) < 0) {
BT_ERR("Can't register misc device with minor %d", minor);
return -EIO;
}
return 0;
}
static void __exit vhci_exit(void)
{
if (misc_deregister(&vhci_miscdev) < 0)
BT_ERR("Can't unregister misc device with minor %d", minor);
}
module_init(vhci_init);
module_exit(vhci_exit);
module_param(minor, int, 0444);
MODULE_PARM_DESC(minor, "Miscellaneous minor device number");
MODULE_AUTHOR("Maxim Krasnyansky <maxk@qualcomm.com>, Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth virtual HCI driver ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");