[media] cx231xx: remove V4L2_FL_LOCK_ALL_FOPS

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@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 36 insertions, 11 deletions

diff --git a/drivers/media/video/cx231xx/cx231xx-video.c b/drivers/media/video/cx231xx/cx231xx-video.c
index 523aa49d6b86..790b28d7f764 100644
--- a/drivers/media/video/cx231xx/cx231xx-video.c
+++ b/drivers/media/video/cx231xx/cx231xx-video.c
@@ -2168,6 +2168,10 @@ static int cx231xx_v4l2_open(struct file *filp)
                 cx231xx_errdev("cx231xx-video.c: Out of memory?!\n");
                 return -ENOMEM;
         }
+        if (mutex_lock_interruptible(&dev->lock)) {
+                kfree(fh);
+                return -ERESTARTSYS;
+        }
         fh->dev = dev;
         fh->radio = radio;
         fh->type = fh_type;
@@ -2226,6 +2230,7 @@ static int cx231xx_v4l2_open(struct file *filp)
                                             sizeof(struct cx231xx_buffer),
                                             fh, &dev->lock);
         }
+        mutex_unlock(&dev->lock);
 
         return errCode;
 }
@@ -2272,11 +2277,11 @@ void cx231xx_release_analog_resources(struct cx231xx *dev)
 }
 
 /*
- * cx231xx_v4l2_close()
+ * cx231xx_close()
  * stops streaming and deallocates all resources allocated by the v4l2
  * calls and ioctls
  */
-static int cx231xx_v4l2_close(struct file *filp)
+static int cx231xx_close(struct file *filp)
 {
         struct cx231xx_fh *fh = filp->private_data;
         struct cx231xx *dev = fh->dev;
@@ -2355,6 +2360,18 @@ static int cx231xx_v4l2_close(struct file *filp)
         return 0;
 }
 
+static int cx231xx_v4l2_close(struct file *filp)
+{
+        struct cx231xx_fh *fh = filp->private_data;
+        struct cx231xx *dev = fh->dev;
+        int rc;
+
+        mutex_lock(&dev->lock);
+        rc = cx231xx_close(filp);
+        mutex_unlock(&dev->lock);
+        return rc;
+}
+
 /*
  * cx231xx_v4l2_read()
  * will allocate buffers when called for the first time
@@ -2378,8 +2395,12 @@ cx231xx_v4l2_read(struct file *filp, char __user *buf, size_t count,
                 if (unlikely(rc < 0))
                         return rc;
 
-                return videobuf_read_stream(&fh->vb_vidq, buf, count, pos, 0,
+                if (mutex_lock_interruptible(&dev->lock))
+                        return -ERESTARTSYS;
+                rc = videobuf_read_stream(&fh->vb_vidq, buf, count, pos, 0,
                                             filp->f_flags & O_NONBLOCK);
+                mutex_unlock(&dev->lock);
+                return rc;
         }
         return 0;
 }
@@ -2404,10 +2425,15 @@ static unsigned int cx231xx_v4l2_poll(struct file *filp, poll_table *wait)
                 return POLLERR;
 
         if ((V4L2_BUF_TYPE_VIDEO_CAPTURE == fh->type) ||
-            (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type))
-                return videobuf_poll_stream(filp, &fh->vb_vidq, wait);
-        else
-                return POLLERR;
+            (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type)) {
+                unsigned int res;
+
+                mutex_lock(&dev->lock);
+                res = videobuf_poll_stream(filp, &fh->vb_vidq, wait);
+                mutex_unlock(&dev->lock);
+                return res;
+        }
+        return POLLERR;
 }
 
 /*
@@ -2428,7 +2454,10 @@ static int cx231xx_v4l2_mmap(struct file *filp, struct vm_area_struct *vma)
         if (unlikely(rc < 0))
                 return rc;
 
+        if (mutex_lock_interruptible(&dev->lock))
+                return -ERESTARTSYS;
         rc = videobuf_mmap_mapper(&fh->vb_vidq, vma);
+        mutex_unlock(&dev->lock);
 
         cx231xx_videodbg("vma start=0x%08lx, size=%ld, ret=%d\n",
                          (unsigned long)vma->vm_start,
@@ -2545,10 +2574,6 @@ static struct video_device *cx231xx_vdev_init(struct cx231xx *dev,
         vfd->release = video_device_release;
         vfd->debug = video_debug;
         vfd->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, &vfd->flags);
 
         snprintf(vfd->name, sizeof(vfd->name), "%s %s", dev->name, type_name);