From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from lb1-smtp-cloud8.xs4all.net ([194.109.24.21]:59852 "EHLO lb1-smtp-cloud8.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751455AbeECOxZ (ORCPT ); Thu, 3 May 2018 10:53:25 -0400 From: Hans Verkuil To: linux-media@vger.kernel.org Cc: Hans Verkuil Subject: [PATCHv13 04/28] media-request: add media_request_get_by_fd Date: Thu, 3 May 2018 16:52:54 +0200 Message-Id: <20180503145318.128315-5-hverkuil@xs4all.nl> In-Reply-To: <20180503145318.128315-1-hverkuil@xs4all.nl> References: <20180503145318.128315-1-hverkuil@xs4all.nl> Sender: linux-media-owner@vger.kernel.org List-ID: From: Hans Verkuil Add media_request_get_by_fd() to find a request based on the file descriptor. The caller has to call media_request_put() for the returned request since this function increments the refcount. Signed-off-by: Hans Verkuil --- drivers/media/media-request.c | 32 ++++++++++++++++++++++++++++++++ include/media/media-request.h | 24 ++++++++++++++++++++++++ 2 files changed, 56 insertions(+) diff --git a/drivers/media/media-request.c b/drivers/media/media-request.c index c216c4ab628b..edc1c3af1959 100644 --- a/drivers/media/media-request.c +++ b/drivers/media/media-request.c @@ -218,6 +218,38 @@ static const struct file_operations request_fops = { .release = media_request_close, }; +struct media_request * +media_request_get_by_fd(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_get_by_fd); + 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 e39122dfd717..997e096d7128 100644 --- a/include/media/media-request.h +++ b/include/media/media-request.h @@ -86,6 +86,24 @@ static inline void media_request_get(struct media_request *req) */ void media_request_put(struct media_request *req); +/** + * media_request_get_by_fd - Get a media request by fd + * + * @mdev: Media device this request belongs to + * @request_fd: The file descriptor of the request + * + * Get the request represented by @request_fd that is owned + * by the media device. + * + * Return a -EPERM error pointer if requests are not supported + * by this driver. Return -ENOENT if the request was not found. + * Return the pointer to the request if found: the caller will + * have to call @media_request_put when it finished using the + * request. + */ +struct media_request * +media_request_get_by_fd(struct media_device *mdev, int request_fd); + /** * media_request_alloc - Allocate the media request * @@ -107,6 +125,12 @@ static inline void media_request_put(struct media_request *req) { } +static inline struct media_request * +media_request_get_by_fd(struct media_device *mdev, int request_fd) +{ + return ERR_PTR(-EPERM); +} + #endif /** -- 2.17.0