[media] dt3155v4l: 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/staging/media/dt3155v4l/dt3155v4l.c b/drivers/staging/media/dt3155v4l/dt3155v4l.c
index ebe5a27c06f5b97219f3f306f9f6d16744b402e4..2e7b711c850135053c14a1ff3291ba9d8bac8649 100644 (file)
--- a/drivers/staging/media/dt3155v4l/dt3155v4l.c
+++ b/drivers/staging/media/dt3155v4l/dt3155v4l.c
@@ -381,6 +381,8 @@ dt3155_open(struct file *filp)
        int ret = 0;
        struct dt3155_priv *pd = video_drvdata(filp);
 
+       if (mutex_lock_interruptible(&pd->mux))
+               return -ERESTARTSYS;
        if (!pd->users) {
                pd->q = kzalloc(sizeof(*pd->q), GFP_KERNEL);
                if (!pd->q) {
@@ -411,6 +413,7 @@ err_request_irq:
        kfree(pd->q);
        pd->q = NULL;
 err_alloc_queue:
+       mutex_unlock(&pd->mux);
        return ret;
 }
 
@@ -419,6 +422,7 @@ dt3155_release(struct file *filp)
 {
        struct dt3155_priv *pd = video_drvdata(filp);
 
+       mutex_lock(&pd->mux);
        pd->users--;
        BUG_ON(pd->users < 0);
        if (!pd->users) {
@@ -429,6 +433,7 @@ dt3155_release(struct file *filp)
                kfree(pd->q);
                pd->q = NULL;
        }
+       mutex_unlock(&pd->mux);
        return 0;
 }
 
@@ -436,24 +441,38 @@ static ssize_t
 dt3155_read(struct file *filp, char __user *user, size_t size, loff_t *loff)
 {
        struct dt3155_priv *pd = video_drvdata(filp);
+       ssize_t res;
 
-       return vb2_read(pd->q, user, size, loff, filp->f_flags & O_NONBLOCK);
+       if (mutex_lock_interruptible(&pd->mux))
+               return -ERESTARTSYS;
+       res = vb2_read(pd->q, user, size, loff, filp->f_flags & O_NONBLOCK);
+       mutex_unlock(&pd->mux);
+       return res;
 }
 
 static unsigned int
 dt3155_poll(struct file *filp, struct poll_table_struct *polltbl)
 {
        struct dt3155_priv *pd = video_drvdata(filp);
+       unsigned int res;
 
-       return vb2_poll(pd->q, filp, polltbl);
+       mutex_lock(&pd->mux);
+       res = vb2_poll(pd->q, filp, polltbl);
+       mutex_unlock(&pd->mux);
+       return res;
 }
 
 static int
 dt3155_mmap(struct file *filp, struct vm_area_struct *vma)
 {
        struct dt3155_priv *pd = video_drvdata(filp);
+       int res;
 
-       return vb2_mmap(pd->q, vma);
+       if (mutex_lock_interruptible(&pd->mux))
+               return -ERESTARTSYS;
+       res = vb2_mmap(pd->q, vma);
+       mutex_unlock(&pd->mux);
+       return res;
 }
 
 static const struct v4l2_file_operations dt3155_fops = {
@@ -898,10 +917,6 @@ dt3155_probe(struct pci_dev *pdev, const struct pci_device_id *id)
        INIT_LIST_HEAD(&pd->dmaq);
        mutex_init(&pd->mux);
        pd->vdev->lock = &pd->mux; /* for locking v4l2_file_operations */
-       /* 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, &pd->vdev->flags);
        spin_lock_init(&pd->lock);
        pd->csr2 = csr2_init;
        pd->config = config_init;