V4L/DVB: videobuf: prepare to make locking optional in videobuf

Currently videobuf uses the vb_lock mutex to lock its data structures.
But this locking will (optionally) move into the v4l2 core, which means
that in that case vb_lock shouldn't be used since the external lock is already
held.

Prepare for this by adding a pointer to such an external mutex and
don't lock if that pointer is set.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/media/video/videobuf-vmalloc.c b/drivers/media/video/videobuf-vmalloc.c
index e7fe31d54f0..91348b3170f 100644
--- a/drivers/media/video/videobuf-vmalloc.c
+++ b/drivers/media/video/videobuf-vmalloc.c
@@ -75,7 +75,7 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
                 struct videobuf_vmalloc_memory *mem;
 
                 dprintk(1, "munmap %p q=%p\n", map, q);
-                mutex_lock(&q->vb_lock);
+                videobuf_queue_lock(q);
 
                 /* We need first to cancel streams, before unmapping */
                 if (q->streaming)
@@ -114,7 +114,7 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
 
                 kfree(map);
 
-                mutex_unlock(&q->vb_lock);
+                videobuf_queue_unlock(q);
         }
 
         return;