From: Hans Verkuil <hans.verkuil@xxxxxxxxx>
Add media_request_find() 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 <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
