[media] vpbe_display: 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, 15 insertions, 7 deletions

diff --git a/drivers/media/video/davinci/vpbe_display.c b/drivers/media/video/davinci/vpbe_display.c
index 6fe7034bea7c..9a05c817462c 100644
--- a/drivers/media/video/davinci/vpbe_display.c
+++ b/drivers/media/video/davinci/vpbe_display.c
@@ -1376,10 +1376,15 @@ static int vpbe_display_mmap(struct file *filep, struct vm_area_struct *vma)
         struct vpbe_fh *fh = filep->private_data;
         struct vpbe_layer *layer = fh->layer;
         struct vpbe_device *vpbe_dev = fh->disp_dev->vpbe_dev;
+        int ret;
 
         v4l2_dbg(1, debug, &vpbe_dev->v4l2_dev, "vpbe_display_mmap\n");
 
-        return videobuf_mmap_mapper(&layer->buffer_queue, vma);
+        if (mutex_lock_interruptible(&layer->opslock))
+                return -ERESTARTSYS;
+        ret = videobuf_mmap_mapper(&layer->buffer_queue, vma);
+        mutex_unlock(&layer->opslock);
+        return ret;
 }
 
 /* vpbe_display_poll(): It is used for select/poll system call
@@ -1392,8 +1397,11 @@ static unsigned int vpbe_display_poll(struct file *filep, poll_table *wait)
         unsigned int err = 0;
 
         v4l2_dbg(1, debug, &vpbe_dev->v4l2_dev, "vpbe_display_poll\n");
-        if (layer->started)
+        if (layer->started) {
+                mutex_lock(&layer->opslock);
                 err = videobuf_poll_stream(filep, &layer->buffer_queue, wait);
+                mutex_unlock(&layer->opslock);
+        }
         return err;
 }
 
@@ -1428,10 +1436,12 @@ static int vpbe_display_open(struct file *file)
         fh->disp_dev = disp_dev;
 
         if (!layer->usrs) {
-
+                if (mutex_lock_interruptible(&layer->opslock))
+                        return -ERESTARTSYS;
                 /* First claim the layer for this device */
                 err = osd_device->ops.request_layer(osd_device,
                                                 layer->layer_info.id);
+                mutex_unlock(&layer->opslock);
                 if (err < 0) {
                         /* Couldn't get layer */
                         v4l2_err(&vpbe_dev->v4l2_dev,
@@ -1469,6 +1479,7 @@ static int vpbe_display_release(struct file *file)
 
         v4l2_dbg(1, debug, &vpbe_dev->v4l2_dev, "vpbe_display_release\n");
 
+        mutex_lock(&layer->opslock);
         /* if this instance is doing IO */
         if (fh->io_allowed) {
                 /* Reset io_usrs member of layer object */
@@ -1503,6 +1514,7 @@ static int vpbe_display_release(struct file *file)
         /* Close the priority */
         v4l2_prio_close(&layer->prio, fh->prio);
         file->private_data = NULL;
+        mutex_unlock(&layer->opslock);
 
         /* Free memory allocated to file handle object */
         kfree(fh);
@@ -1620,10 +1632,6 @@ static __devinit int init_vpbe_layer(int i, struct vpbe_display *disp_dev,
         vbd->ioctl_ops  = &vpbe_ioctl_ops;
         vbd->minor      = -1;
         vbd->v4l2_dev   = &disp_dev->vpbe_dev->v4l2_dev;
-        /* 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, &vbd->flags);
         vbd->lock       = &vpbe_display_layer->opslock;
 
         if (disp_dev->vpbe_dev->current_timings.timings_type &