[media] fsl-viu: 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>

diff --git a/drivers/media/video/fsl-viu.c b/drivers/media/video/fsl-viu.c
index 777486f7cadb65761e25d393e1c16f043426eaea..20f981008fafccf7cfd53f82dbe1176da6b4178d 100644 (file)
--- a/drivers/media/video/fsl-viu.c
+++ b/drivers/media/video/fsl-viu.c
@@ -1279,10 +1279,16 @@ static int viu_open(struct file *file)
        dprintk(1, "open minor=%d type=%s users=%d\n", minor,
                v4l2_type_names[V4L2_BUF_TYPE_VIDEO_CAPTURE], dev->users);
 
+       if (mutex_lock_interruptible(&dev->lock)) {
+               dev->users--;
+               return -ERESTARTSYS;
+       }
+
        /* allocate and initialize per filehandle data */
        fh = kzalloc(sizeof(*fh), GFP_KERNEL);
        if (!fh) {
                dev->users--;
+               mutex_unlock(&dev->lock);
                return -ENOMEM;
        }
 
@@ -1325,6 +1331,7 @@ static int viu_open(struct file *file)
                                       fh->type, V4L2_FIELD_INTERLACED,
                                       sizeof(struct viu_buf), fh,
                                       &fh->dev->lock);
+       mutex_unlock(&dev->lock);
        return 0;
 }
 
@@ -1340,9 +1347,12 @@ static ssize_t viu_read(struct file *file, char __user *data, size_t count,
                dev->ovenable = 0;
 
        if (fh->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+               if (mutex_lock_interruptible(&dev->lock))
+                       return -ERESTARTSYS;
                viu_start_dma(dev);
                ret = videobuf_read_stream(&fh->vb_vidq, data, count,
                                ppos, 0, file->f_flags & O_NONBLOCK);
+               mutex_unlock(&dev->lock);
                return ret;
        }
        return 0;
@@ -1352,11 +1362,16 @@ static unsigned int viu_poll(struct file *file, struct poll_table_struct *wait)
 {
        struct viu_fh *fh = file->private_data;
        struct videobuf_queue *q = &fh->vb_vidq;
+       struct viu_dev *dev = fh->dev;
+       unsigned int res;
 
        if (V4L2_BUF_TYPE_VIDEO_CAPTURE != fh->type)
                return POLLERR;
 
-       return videobuf_poll_stream(file, q, wait);
+       mutex_lock(&dev->lock);
+       res = videobuf_poll_stream(file, q, wait);
+       mutex_unlock(&dev->lock);
+       return res;
 }
 
 static int viu_release(struct file *file)
@@ -1365,9 +1380,11 @@ static int viu_release(struct file *file)
        struct viu_dev *dev = fh->dev;
        int minor = video_devdata(file)->minor;
 
+       mutex_lock(&dev->lock);
        viu_stop_dma(dev);
        videobuf_stop(&fh->vb_vidq);
        videobuf_mmap_free(&fh->vb_vidq);
+       mutex_unlock(&dev->lock);
 
        kfree(fh);
 
@@ -1394,11 +1411,15 @@ void viu_reset(struct viu_reg *reg)
 static int viu_mmap(struct file *file, struct vm_area_struct *vma)
 {
        struct viu_fh *fh = file->private_data;
+       struct viu_dev *dev = fh->dev;
        int ret;
 
        dprintk(1, "mmap called, vma=0x%08lx\n", (unsigned long)vma);
 
+       if (mutex_lock_interruptible(&dev->lock))
+               return -ERESTARTSYS;
        ret = videobuf_mmap_mapper(&fh->vb_vidq, vma);
+       mutex_unlock(&dev->lock);
 
        dprintk(1, "vma start=0x%08lx, size=%ld, ret=%d\n",
                (unsigned long)vma->vm_start,
@@ -1544,10 +1565,6 @@ static int __devinit viu_of_probe(struct platform_device *op)
 
        /* initialize locks */
        mutex_init(&viu_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, &viu_dev->vdev->flags);
        viu_dev->vdev->lock = &viu_dev->lock;
        spin_lock_init(&viu_dev->slock);