[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>

1 files changed, 23 insertions, 11 deletions

diff --git a/drivers/media/video/davinci/vpif_display.c b/drivers/media/video/davinci/vpif_display.c
index e129c98921ad..4a24848c1a66 100644
--- 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 */