From: Laurent Pinchart Date: Fri, 18 Mar 2022 17:44:35 +0000 (+0100) Subject: media: videobuf2-v4l2: Expose vb2_queue_is_busy() to drivers X-Git-Tag: v5.19-rc1~179^2~119 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=7101d1279917e5c7fe897c275c5a0727fe90f3e3;p=tomoyo%2Ftomoyo-test1.git media: videobuf2-v4l2: Expose vb2_queue_is_busy() to drivers vb2 queue ownership is managed by the ioctl handler helpers (vb2_ioctl_*). There are however use cases where drivers can benefit from checking queue ownership, for instance when open-coding an ioctl handler that needs to perform additional checks before calling the corresponding vb2 operation. Expose the vb2_queue_is_busy() function in the videobuf2-v4l2.h header, and change its first argument to a struct vb2_queue pointer as the function name implies it operates on a queue, not a video_device. Signed-off-by: Laurent Pinchart Reviewed-by: Kieran Bingham Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/common/videobuf2/videobuf2-v4l2.c b/drivers/media/common/videobuf2/videobuf2-v4l2.c index 6edf4508c636..075d24ebf44c 100644 --- a/drivers/media/common/videobuf2/videobuf2-v4l2.c +++ b/drivers/media/common/videobuf2/videobuf2-v4l2.c @@ -977,12 +977,6 @@ EXPORT_SYMBOL_GPL(vb2_poll); * and so they simplify the driver code. */ -/* The queue is busy if there is a owner and you are not that owner. */ -static inline bool vb2_queue_is_busy(struct video_device *vdev, struct file *file) -{ - return vdev->queue->owner && vdev->queue->owner != file->private_data; -} - /* vb2 ioctl helpers */ int vb2_ioctl_reqbufs(struct file *file, void *priv, @@ -997,7 +991,7 @@ int vb2_ioctl_reqbufs(struct file *file, void *priv, p->flags = flags; if (res) return res; - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; res = vb2_core_reqbufs(vdev->queue, p->memory, p->flags, &p->count); /* If count == 0, then the owner has released all buffers and he @@ -1026,7 +1020,7 @@ int vb2_ioctl_create_bufs(struct file *file, void *priv, return res != -EBUSY ? res : 0; if (res) return res; - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; res = vb2_create_bufs(vdev->queue, p); @@ -1041,7 +1035,7 @@ int vb2_ioctl_prepare_buf(struct file *file, void *priv, { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_prepare_buf(vdev->queue, vdev->v4l2_dev->mdev, p); } @@ -1060,7 +1054,7 @@ int vb2_ioctl_qbuf(struct file *file, void *priv, struct v4l2_buffer *p) { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_qbuf(vdev->queue, vdev->v4l2_dev->mdev, p); } @@ -1070,7 +1064,7 @@ int vb2_ioctl_dqbuf(struct file *file, void *priv, struct v4l2_buffer *p) { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_dqbuf(vdev->queue, p, file->f_flags & O_NONBLOCK); } @@ -1080,7 +1074,7 @@ int vb2_ioctl_streamon(struct file *file, void *priv, enum v4l2_buf_type i) { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_streamon(vdev->queue, i); } @@ -1090,7 +1084,7 @@ int vb2_ioctl_streamoff(struct file *file, void *priv, enum v4l2_buf_type i) { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_streamoff(vdev->queue, i); } @@ -1100,7 +1094,7 @@ int vb2_ioctl_expbuf(struct file *file, void *priv, struct v4l2_exportbuffer *p) { struct video_device *vdev = video_devdata(file); - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) return -EBUSY; return vb2_expbuf(vdev->queue, p); } @@ -1152,7 +1146,7 @@ ssize_t vb2_fop_write(struct file *file, const char __user *buf, return -EINVAL; if (lock && mutex_lock_interruptible(lock)) return -ERESTARTSYS; - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) goto exit; err = vb2_write(vdev->queue, buf, count, ppos, file->f_flags & O_NONBLOCK); @@ -1176,7 +1170,7 @@ ssize_t vb2_fop_read(struct file *file, char __user *buf, return -EINVAL; if (lock && mutex_lock_interruptible(lock)) return -ERESTARTSYS; - if (vb2_queue_is_busy(vdev, file)) + if (vb2_queue_is_busy(vdev->queue, file)) goto exit; err = vb2_read(vdev->queue, buf, count, ppos, file->f_flags & O_NONBLOCK); diff --git a/include/media/videobuf2-v4l2.h b/include/media/videobuf2-v4l2.h index b66585e304e2..d818d9707695 100644 --- a/include/media/videobuf2-v4l2.h +++ b/include/media/videobuf2-v4l2.h @@ -302,10 +302,29 @@ __poll_t vb2_poll(struct vb2_queue *q, struct file *file, poll_table *wait); * The following functions are not part of the vb2 core API, but are simple * helper functions that you can use in your struct v4l2_file_operations, * struct v4l2_ioctl_ops and struct vb2_ops. They will serialize if vb2_queue->lock - * or video_device->lock is set, and they will set and test vb2_queue->owner - * to check if the calling filehandle is permitted to do the queuing operation. + * or video_device->lock is set, and they will set and test the queue owner + * (vb2_queue->owner) to check if the calling filehandle is permitted to do the + * queuing operation. */ +/** + * vb2_queue_is_busy() - check if the queue is busy + * @q: pointer to &struct vb2_queue with videobuf2 queue. + * @file: file through which the vb2 queue access is performed + * + * The queue is considered busy if it has an owner and the owner is not the + * @file. + * + * Queue ownership is acquired and checked by some of the v4l2_ioctl_ops helpers + * below. Drivers can also use this function directly when they need to + * open-code ioctl handlers, for instance to add additional checks between the + * queue ownership test and the call to the corresponding vb2 operation. + */ +static inline bool vb2_queue_is_busy(struct vb2_queue *q, struct file *file) +{ + return q->owner && q->owner != file->private_data; +} + /* struct v4l2_ioctl_ops helpers */ int vb2_ioctl_reqbufs(struct file *file, void *priv,