[media] sh_vou: 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, 19 insertions, 6 deletions

diff --git a/drivers/media/video/sh_vou.c b/drivers/media/video/sh_vou.c
index 8fd1874382c6..9f62fd89ab57 100644
--- a/drivers/media/video/sh_vou.c
+++ b/drivers/media/video/sh_vou.c
@@ -1171,6 +1171,8 @@ static int sh_vou_open(struct file *file)
 
         file->private_data = vou_file;
 
+        if (mutex_lock_interruptible(&vou_dev->fop_lock))
+                return -ERESTARTSYS;
         if (atomic_inc_return(&vou_dev->use_count) == 1) {
                 int ret;
                 /* First open */
@@ -1181,6 +1183,7 @@ static int sh_vou_open(struct file *file)
                         atomic_dec(&vou_dev->use_count);
                         pm_runtime_put(vdev->v4l2_dev->dev);
                         vou_dev->status = SH_VOU_IDLE;
+                        mutex_unlock(&vou_dev->fop_lock);
                         return ret;
                 }
         }
@@ -1191,6 +1194,7 @@ static int sh_vou_open(struct file *file)
                                        V4L2_FIELD_NONE,
                                        sizeof(struct videobuf_buffer), vdev,
                                        &vou_dev->fop_lock);
+        mutex_unlock(&vou_dev->fop_lock);
 
         return 0;
 }
@@ -1204,10 +1208,12 @@ static int sh_vou_release(struct file *file)
         dev_dbg(vou_file->vbq.dev, "%s()\n", __func__);
 
         if (!atomic_dec_return(&vou_dev->use_count)) {
+                mutex_lock(&vou_dev->fop_lock);
                 /* Last close */
                 vou_dev->status = SH_VOU_IDLE;
                 sh_vou_reg_a_set(vou_dev, VOUER, 0, 0x101);
                 pm_runtime_put(vdev->v4l2_dev->dev);
+                mutex_unlock(&vou_dev->fop_lock);
         }
 
         file->private_data = NULL;
@@ -1218,20 +1224,31 @@ static int sh_vou_release(struct file *file)
 
 static int sh_vou_mmap(struct file *file, struct vm_area_struct *vma)
 {
+        struct sh_vou_device *vou_dev = video_get_drvdata(vdev);
         struct sh_vou_file *vou_file = file->private_data;
+        int ret;
 
         dev_dbg(vou_file->vbq.dev, "%s()\n", __func__);
 
-        return videobuf_mmap_mapper(&vou_file->vbq, vma);
+        if (mutex_lock_interruptible(&vou_dev->fop_lock))
+                return -ERESTARTSYS;
+        ret = videobuf_mmap_mapper(&vou_file->vbq, vma);
+        mutex_unlock(&vou_dev->fop_lock);
+        return ret;
 }
 
 static unsigned int sh_vou_poll(struct file *file, poll_table *wait)
 {
+        struct sh_vou_device *vou_dev = video_get_drvdata(vdev);
         struct sh_vou_file *vou_file = file->private_data;
+        unsigned int res;
 
         dev_dbg(vou_file->vbq.dev, "%s()\n", __func__);
 
-        return videobuf_poll_stream(file, &vou_file->vbq, wait);
+        mutex_lock(&vou_dev->fop_lock);
+        res = videobuf_poll_stream(file, &vou_file->vbq, wait);
+        mutex_unlock(&vou_dev->fop_lock);
+        return res;
 }
 
 static int sh_vou_g_chip_ident(struct file *file, void *fh,
@@ -1390,10 +1407,6 @@ static int __devinit sh_vou_probe(struct platform_device *pdev)
         vdev->v4l2_dev = &vou_dev->v4l2_dev;
         vdev->release = video_device_release;
         vdev->lock = &vou_dev->fop_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, &vdev->flags);
 
         vou_dev->vdev = vdev;
         video_set_drvdata(vdev, vou_dev);