[media] vpif_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>

diff --git a/drivers/media/video/davinci/vpif_display.c b/drivers/media/video/davinci/vpif_display.c
index e129c98921ad493b0b8ea90562d2878325218fc5..4a24848c1a665df0df0e05eb610550e49231fb6f 100644 (file)
--- a/drivers/media/video/davinci/vpif_display.c
+++ b/drivers/media/video/davinci/vpif_display.c
@@ -695,10 +695,15 @@ static int vpif_mmap(struct file *filep, struct vm_area_struct *vma)
        struct vpif_fh *fh = filep->private_data;
        struct channel_obj *ch = fh->channel;
        struct common_obj *common = &(ch->common[VPIF_VIDEO_INDEX]);
+       int ret;
 
        vpif_dbg(2, debug, "vpif_mmap\n");
 
-       return vb2_mmap(&common->buffer_queue, vma);
+       if (mutex_lock_interruptible(&common->lock))
+               return -ERESTARTSYS;
+       ret = vb2_mmap(&common->buffer_queue, vma);
+       mutex_unlock(&common->lock);
+       return ret;
 }
 
 /*
@@ -709,11 +714,15 @@ static unsigned int vpif_poll(struct file *filep, poll_table *wait)
        struct vpif_fh *fh = filep->private_data;
        struct channel_obj *ch = fh->channel;
        struct common_obj *common = &ch->common[VPIF_VIDEO_INDEX];
+       unsigned int res = 0;
 
-       if (common->started)
-               return vb2_poll(&common->buffer_queue, filep, wait);
+       if (common->started) {
+               mutex_lock(&common->lock);
+               res = vb2_poll(&common->buffer_queue, filep, wait);
+               mutex_unlock(&common->lock);
+       }
 
-       return 0;
+       return res;
 }
 
 /*
@@ -723,10 +732,10 @@ static unsigned int vpif_poll(struct file *filep, poll_table *wait)
 static int vpif_open(struct file *filep)
 {
        struct video_device *vdev = video_devdata(filep);
-       struct channel_obj *ch = NULL;
-       struct vpif_fh *fh = NULL;
+       struct channel_obj *ch = video_get_drvdata(vdev);
+       struct common_obj *common = &ch->common[VPIF_VIDEO_INDEX];
+       struct vpif_fh *fh;
 
-       ch = video_get_drvdata(vdev);
        /* Allocate memory for the file handle object */
        fh = kzalloc(sizeof(struct vpif_fh), GFP_KERNEL);
        if (fh == NULL) {
@@ -734,6 +743,10 @@ static int vpif_open(struct file *filep)
                return -ENOMEM;
        }
 
+       if (mutex_lock_interruptible(&common->lock)) {
+               kfree(fh);
+               return -ERESTARTSYS;
+       }
        /* store pointer to fh in private_data member of filep */
        filep->private_data = fh;
        fh->channel = ch;
@@ -751,6 +764,7 @@ static int vpif_open(struct file *filep)
        /* Initialize priority of this instance to default priority */
        fh->prio = V4L2_PRIORITY_UNSET;
        v4l2_prio_open(&ch->prio, &fh->prio);
+       mutex_unlock(&common->lock);
 
        return 0;
 }
@@ -765,6 +779,7 @@ static int vpif_release(struct file *filep)
        struct channel_obj *ch = fh->channel;
        struct common_obj *common = &ch->common[VPIF_VIDEO_INDEX];
 
+       mutex_lock(&common->lock);
        /* if this instance is doing IO */
        if (fh->io_allowed[VPIF_VIDEO_INDEX]) {
                /* Reset io_usrs member of channel object */
@@ -799,6 +814,7 @@ static int vpif_release(struct file *filep)
        v4l2_prio_close(&ch->prio, fh->prio);
        filep->private_data = NULL;
        fh->initialized = 0;
+       mutex_unlock(&common->lock);
        kfree(fh);
 
        return 0;
@@ -1789,10 +1805,6 @@ static __init int vpif_probe(struct platform_device *pdev)
                v4l2_prio_init(&ch->prio);
                ch->common[VPIF_VIDEO_INDEX].fmt.type =
                                                V4L2_BUF_TYPE_VIDEO_OUTPUT;
-               /* 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, &ch->video_dev->flags);
                ch->video_dev->lock = &common->lock;
 
                /* register video device */