media: sta2x11: Add video_device and vb2_queue locks

Currently, this driver does not serialize its video4linux
ioctls, which is a bug, as race conditions might appear.

In addition, video_device and vb2_queue locks are now both
mandatory. Add them, and implement wait_prepare and
wait_finish.

To stay on the safe side, this commit uses a single mutex
for both locks. Better latency can be obtained by separating
these if needed.

Signed-off-by: Ezequiel Garcia <ezequiel@collabora.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>

diff --git a/drivers/media/pci/sta2x11/sta2x11_vip.c b/drivers/media/pci/sta2x11/sta2x11_vip.c
index 069c4a853346275309ee9f46d4119c10a5d7ee3f..da2b2a2292d043f887606a90f309088482504dec 100644 (file)
--- a/drivers/media/pci/sta2x11/sta2x11_vip.c
+++ b/drivers/media/pci/sta2x11/sta2x11_vip.c
@@ -145,6 +145,7 @@ struct sta2x11_vip {
        unsigned int sequence;
        struct vip_buffer *active; /* current active buffer */
        spinlock_t lock; /* Used in videobuf2 callback */
+       struct mutex v4l_lock;
 
        /* Interrupt counters */
        int tcount, bcount;
@@ -385,6 +386,8 @@ static const struct vb2_ops vip_video_qops = {
        .buf_queue              = buffer_queue,
        .start_streaming        = start_streaming,
        .stop_streaming         = stop_streaming,
+       .wait_prepare           = vb2_ops_wait_prepare,
+       .wait_finish            = vb2_ops_wait_finish,
 };
 
 
@@ -870,6 +873,7 @@ static int sta2x11_vip_init_buffer(struct sta2x11_vip *vip)
        vip->vb_vidq.mem_ops = &vb2_dma_contig_memops;
        vip->vb_vidq.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
        vip->vb_vidq.dev = &vip->pdev->dev;
+       vip->vb_vidq.lock = &vip->v4l_lock;
        err = vb2_queue_init(&vip->vb_vidq);
        if (err)
                return err;
@@ -1034,6 +1038,7 @@ static int sta2x11_vip_init_one(struct pci_dev *pdev,
        vip->std = V4L2_STD_PAL;
        vip->format = formats_50[0];
        vip->config = config;
+       mutex_init(&vip->v4l_lock);
 
        ret = sta2x11_vip_init_controls(vip);
        if (ret)
@@ -1080,6 +1085,7 @@ static int sta2x11_vip_init_one(struct pci_dev *pdev,
        vip->video_dev = video_dev_template;
        vip->video_dev.v4l2_dev = &vip->v4l2_dev;
        vip->video_dev.queue = &vip->vb_vidq;
+       vip->video_dev.lock = &vip->v4l_lock;
        video_set_drvdata(&vip->video_dev, vip);
 
        ret = video_register_device(&vip->video_dev, VFL_TYPE_GRABBER, -1);