From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Add proper locking to the file operations, allowing for the removal
of the V4L2_FL_LOCK_ALL_FOPS flag.
Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
---
drivers/media/video/s2255drv.c | 42 ++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 21 deletions(-)
diff --git a/drivers/media/video/s2255drv.c b/drivers/media/video/s2255drv.c
index 01c2179..0001f1d 100644
--- a/drivers/media/video/s2255drv.c
+++ b/drivers/media/video/s2255drv.c
@@ -258,7 +258,6 @@ struct s2255_dev {
atomic_t num_channels;
int frames;
struct mutex lock; /* channels[].vdev.lock */
- struct mutex open_lock;
struct usb_device *udev;
struct usb_interface *interface;
u8 read_endpoint;
@@ -1684,7 +1683,7 @@ static int vidioc_enum_frameintervals(struct file *file, void *priv,
return 0;
}
-static int s2255_open(struct file *file)
+static int __s2255_open(struct file *file)
{
struct video_device *vdev = video_devdata(file);
struct s2255_channel *channel = video_drvdata(file);
@@ -1694,16 +1693,9 @@ static int s2255_open(struct file *file)
int state;
dprintk(1, "s2255: open called (dev=%s)\n",
video_device_node_name(vdev));
- /*
- * open lock necessary to prevent multiple instances
- * of v4l-conf (or other programs) from simultaneously
- * reloading firmware.
- */
- mutex_lock(&dev->open_lock);
state = atomic_read(&dev->fw_data->fw_state);
switch (state) {
case S2255_FW_DISCONNECTING:
- mutex_unlock(&dev->open_lock);
return -ENODEV;
case S2255_FW_FAILED:
s2255_dev_err(&dev->udev->dev,
@@ -1742,11 +1734,9 @@ static int s2255_open(struct file *file)
break;
case S2255_FW_FAILED:
printk(KERN_INFO "2255 firmware load failed.\n");
- mutex_unlock(&dev->open_lock);
return -ENODEV;
case S2255_FW_DISCONNECTING:
printk(KERN_INFO "%s: disconnecting\n", __func__);
- mutex_unlock(&dev->open_lock);
return -ENODEV;
case S2255_FW_LOADED_DSPWAIT:
case S2255_FW_NOTLOADED:
@@ -1760,14 +1750,11 @@ static int s2255_open(struct file *file)
*/
atomic_set(&dev->fw_data->fw_state,
S2255_FW_FAILED);
- mutex_unlock(&dev->open_lock);
return -EAGAIN;
default:
printk(KERN_INFO "%s: unknown state\n", __func__);
- mutex_unlock(&dev->open_lock);
return -EFAULT;
}
- mutex_unlock(&dev->open_lock);
/* allocate + initialize per filehandle data */
fh = kzalloc(sizeof(*fh), GFP_KERNEL);
if (NULL == fh)
@@ -1798,16 +1785,30 @@ static int s2255_open(struct file *file)
return 0;
}
+static int s2255_open(struct file *file)
+{
+ struct video_device *vdev = video_devdata(file);
+ int ret;
+
+ if (mutex_lock_interruptible(vdev->lock))
+ return -ERESTARTSYS;
+ ret = __s2255_open(file);
+ mutex_unlock(vdev->lock);
+ return ret;
+}
static unsigned int s2255_poll(struct file *file,
struct poll_table_struct *wait)
{
struct s2255_fh *fh = file->private_data;
+ struct s2255_dev *dev = fh->dev;
int rc;
dprintk(100, "%s\n", __func__);
if (V4L2_BUF_TYPE_VIDEO_CAPTURE != fh->type)
return POLLERR;
+ mutex_lock(&dev->lock);
rc = videobuf_poll_stream(file, &fh->vb_vidq, wait);
+ mutex_unlock(&dev->lock);
return rc;
}
@@ -1827,7 +1828,6 @@ static void s2255_destroy(struct s2255_dev *dev)
kfree(dev->fw_data);
/* reset the DSP so firmware can be reloaded next time */
s2255_reset_dsppower(dev);
- mutex_destroy(&dev->open_lock);
mutex_destroy(&dev->lock);
usb_put_dev(dev->udev);
v4l2_device_unregister(&dev->v4l2_dev);
@@ -1843,6 +1843,7 @@ static int s2255_release(struct file *file)
struct s2255_channel *channel = fh->channel;
if (!dev)
return -ENODEV;
+ mutex_lock(&dev->lock);
/* turn off stream */
if (res_check(fh)) {
if (channel->b_acquire)
@@ -1851,6 +1852,7 @@ static int s2255_release(struct file *file)
res_free(fh);
}
videobuf_mmap_free(&fh->vb_vidq);
+ mutex_unlock(&dev->lock);
dprintk(1, "%s (dev=%s)\n", __func__, video_device_node_name(vdev));
kfree(fh);
return 0;
@@ -1859,12 +1861,16 @@ static int s2255_release(struct file *file)
static int s2255_mmap_v4l(struct file *file, struct vm_area_struct *vma)
{
struct s2255_fh *fh = file->private_data;
+ struct s2255_dev *dev = fh->dev;
int ret;
if (!fh)
return -ENODEV;
dprintk(4, "%s, vma=0x%08lx\n", __func__, (unsigned long)vma);
+ if (mutex_lock_interruptible(&dev->lock))
+ return -ERESTARTSYS;
ret = videobuf_mmap_mapper(&fh->vb_vidq, vma);
+ mutex_unlock(&dev->lock);
dprintk(4, "%s vma start=0x%08lx, size=%ld, ret=%d\n", __func__,
(unsigned long)vma->vm_start,
(unsigned long)vma->vm_end - (unsigned long)vma->vm_start, ret);
@@ -1944,10 +1950,6 @@ static int s2255_probe_v4l(struct s2255_dev *dev)
/* register 4 video devices */
channel->vdev = template;
channel->vdev.lock = &dev->lock;
- /* Locking in file operations other than ioctl should be done
- by the driver, not the V4L2 core.
- This driver needs auditing so that this flag can be removed. */
- set_bit(V4L2_FL_LOCK_ALL_FOPS, &channel->vdev.flags);
channel->vdev.v4l2_dev = &dev->v4l2_dev;
video_set_drvdata(&channel->vdev, channel);
if (video_nr == -1)
@@ -2535,7 +2537,6 @@ static int s2255_probe(struct usb_interface *interface,
if (!dev->fw_data)
goto errorFWDATA1;
mutex_init(&dev->lock);
- mutex_init(&dev->open_lock);
/* grab usb_device and save it */
dev->udev = usb_get_dev(interface_to_usbdev(interface));
if (dev->udev == NULL) {
@@ -2637,7 +2638,6 @@ errorEP:
usb_put_dev(dev->udev);
errorUDEV:
kfree(dev->fw_data);
- mutex_destroy(&dev->open_lock);
mutex_destroy(&dev->lock);
errorFWDATA1:
kfree(dev);
--
1.7.10
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