openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

media: davinci_vpfe: 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>
This commit is contained in:
Ezequiel Garcia 2018-06-15 15:07:29 -04:00 committed by Mauro Carvalho Chehab
parent e5e4c9c962
commit 4e55969f23
2 changed files with 6 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/staging/media/davinci_vpfe/vpfe_video.c
View File

@ -1312,6 +1312,8 @@ static const struct vb2_ops video_qops = {
.stop_streaming = vpfe_stop_streaming,
.buf_cleanup = vpfe_buf_cleanup,
.buf_queue = vpfe_buffer_queue,
.wait_prepare = vb2_ops_wait_prepare,
.wait_finish = vb2_ops_wait_finish,
};
/*
@ -1357,6 +1359,7 @@ static int vpfe_reqbufs(struct file *file, void *priv,
q->buf_struct_size = sizeof(struct vpfe_cap_buffer);
q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
q->dev = vpfe_dev->pdev;
q->lock = &video->lock;
ret = vb2_queue_init(q);
if (ret) {
@ -1598,17 +1601,18 @@ int vpfe_video_init(struct vpfe_video_device *video, const char *name)
return -EINVAL;
}
/* Initialize field of video device */
mutex_init(&video->lock);
video->video_dev.release = video_device_release;
video->video_dev.fops = &vpfe_fops;
video->video_dev.ioctl_ops = &vpfe_ioctl_ops;
video->video_dev.minor = -1;
video->video_dev.tvnorms = 0;
video->video_dev.lock = &video->lock;
snprintf(video->video_dev.name, sizeof(video->video_dev.name),
"DAVINCI VIDEO %s %s", name, direction);
spin_lock_init(&video->irqlock);
spin_lock_init(&video->dma_queue_lock);
mutex_init(&video->lock);
ret = media_entity_pads_init(&video->video_dev.entity,
1, &video->pad);
if (ret < 0)

2
drivers/staging/media/davinci_vpfe/vpfe_video.h
View File

@ -128,7 +128,7 @@ struct vpfe_video_device {
spinlock_t irqlock;
/* IRQ lock for DMA queue */
spinlock_t dma_queue_lock;
/* lock used to access this structure */
/* lock used to serialize all video4linux ioctls */
struct mutex lock;
/* number of users performing IO */
u32 io_usrs;