linux/drivers/bluetooth/hci_vhci.c
Arjan van de Ven 2b8693c061 [PATCH] mark struct file_operations const 3
Many struct file_operations in the kernel can be "const".  Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data.  In addition it'll catch accidental writes at compile time to
these shared resources.

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12 09:48:45 -08:00

381 lines
7.6 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/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 loff_t vhci_llseek(struct file *file, loff_t offset, int origin)
{
return -ESPIPE;
}
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);
hdev = hci_alloc_dev();
if (!hdev) {
kfree(data);
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);
return -EBUSY;
}
file->private_data = data;
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;
err = fasync_helper(fd, file, on, &data->fasync);
if (err < 0)
return err;
if (on)
data->flags |= VHCI_FASYNC;
else
data->flags &= ~VHCI_FASYNC;
return 0;
}
static const struct file_operations vhci_fops = {
.owner = THIS_MODULE,
.llseek = vhci_llseek,
.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");