From: Rob Clark rob@ti.com
Works in a similar way to get_file(), and is needed in cases such as when the exporter needs to also keep a reference to the dmabuf (that is later released with a dma_buf_put()), and possibly other similar cases.
Signed-off-by: Rob Clark rob@ti.com --- Minor update on original to add a missing #include
include/linux/dma-buf.h | 15 +++++++++++++++ 1 files changed, 15 insertions(+), 0 deletions(-)
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index 891457a..bc4203dc 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -30,6 +30,7 @@ #include <linux/scatterlist.h> #include <linux/list.h> #include <linux/dma-mapping.h> +#include <linux/fs.h>
struct dma_buf; struct dma_buf_attachment; @@ -110,6 +111,20 @@ struct dma_buf_attachment { void *priv; };
+/** + * get_dma_buf - convenience wrapper for get_file. + * @dmabuf: [in] pointer to dma_buf + * + * Increments the reference count on the dma-buf, needed in case of drivers + * that either need to create additional references to the dmabuf on the + * kernel side. For example, an exporter that needs to keep a dmabuf ptr + * so that subsequent exports don't create a new dmabuf. + */ +static inline void get_dma_buf(struct dma_buf *dmabuf) +{ + get_file(dmabuf->file); +} + #ifdef CONFIG_DMA_SHARED_BUFFER struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, struct device *dev);