On 03/05/18 00:06, Sakari Ailus wrote:
> Hi Hans,
>
> Thanks for the update.
>
> On Tue, May 01, 2018 at 11:00:27AM +0200, Hans Verkuil wrote:
>> From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>>
>> Add media_request_find() to find a request based on the file
>> descriptor.
>
> What would you think of calling this media_request_get_by_fd() instead?
>
> I think what the function does has changed over the time a bit but the name
> has stayed.
Good idea, done.
Regards,
Hans
>
>>
>> The caller has to call media_request_put() for the returned
>> request since this function increments the refcount.
>>
>> Signed-off-by: Hans Verkuil <hans.verkuil@xxxxxxxxx>
>> ---
>> drivers/media/media-request.c | 44 +++++++++++++++++++++++++++++++++++
>> include/media/media-request.h | 10 ++++++++
>> 2 files changed, 54 insertions(+)
>>
>> diff --git a/drivers/media/media-request.c b/drivers/media/media-request.c
>> index 22881d5700c8..a186db290d51 100644
>> --- a/drivers/media/media-request.c
>> +++ b/drivers/media/media-request.c
>> @@ -234,6 +234,50 @@ static const struct file_operations request_fops = {
>> .release = media_request_close,
>> };
>>
>> +/**
>> + * media_request_find - Find a request based on the file descriptor
>> + * @mdev: The media device
>> + * @request_fd: The request file handle
>> + *
>> + * Find and return the request associated with the given file descriptor, or
>> + * an error if no such request exists.
>> + *
>> + * When the function returns a request it increases its reference count. The
>> + * caller is responsible for releasing the reference by calling
>> + * media_request_put() on the request.
>> + */
>> +struct media_request *
>> +media_request_find(struct media_device *mdev, int request_fd)
>> +{
>> + struct file *filp;
>> + struct media_request *req;
>> +
>> + if (!mdev || !mdev->ops ||
>> + !mdev->ops->req_validate || !mdev->ops->req_queue)
>> + return ERR_PTR(-EPERM);
>> +
>> + filp = fget(request_fd);
>> + if (!filp)
>> + return ERR_PTR(-ENOENT);
>> +
>> + if (filp->f_op != &request_fops)
>> + goto err_fput;
>> + req = filp->private_data;
>> + if (req->mdev != mdev)
>> + goto err_fput;
>> +
>> + media_request_get(req);
>> + fput(filp);
>> +
>> + return req;
>> +
>> +err_fput:
>> + fput(filp);
>> +
>> + return ERR_PTR(-ENOENT);
>> +}
>> +EXPORT_SYMBOL_GPL(media_request_find);
>> +
>> int media_request_alloc(struct media_device *mdev,
>> struct media_request_alloc *alloc)
>> {
>> diff --git a/include/media/media-request.h b/include/media/media-request.h
>> index 9051dfbc7d30..ce62fe74ebd6 100644
>> --- a/include/media/media-request.h
>> +++ b/include/media/media-request.h
>> @@ -70,6 +70,9 @@ static inline void media_request_get(struct media_request *req)
>> void media_request_put(struct media_request *req);
>> void media_request_cancel(struct media_request *req);
>>
>> +struct media_request *
>> +media_request_find(struct media_device *mdev, int request_fd);
>> +
>> int media_request_alloc(struct media_device *mdev,
>> struct media_request_alloc *alloc);
>> #else
>> @@ -85,6 +88,12 @@ static inline void media_request_cancel(struct media_request *req)
>> {
>> }
>>
>> +static inline struct media_request *
>> +media_request_find(struct media_device *mdev, int request_fd)
>> +{
>> + return ERR_PTR(-ENOENT);
>> +}
>> +
>> #endif
>>
>> struct media_request_object_ops {
>> @@ -188,6 +197,7 @@ static inline void media_request_object_unbind(struct media_request_object *obj)
>> static inline void media_request_object_complete(struct media_request_object *obj)
>> {
>> }
>> +
>> #endif
>>
>> #endif
>> --
>> 2.17.0
>>
>
