Re: [PATCH v3 9/9] xen/gntdev: Implement dma-buf import functionality

Boris Ostrovsky
2018-06-13T03:15:01Z

On 06/12/2018 09:42 AM, Oleksandr Andrushchenko wrote:

> int gntdev_dmabuf_imp_release(struct gntdev_dmabuf_priv *priv, u32 fd)
> {
> - return -EINVAL;
> + struct gntdev_dmabuf *gntdev_dmabuf;
> + struct dma_buf_attachment *attach;
> + struct dma_buf *dma_buf;
> +
> + gntdev_dmabuf = dmabuf_imp_find_unlink(priv, fd);
> + if (IS_ERR(gntdev_dmabuf))
> + return PTR_ERR(gntdev_dmabuf);
> +
> + pr_debug("Releasing DMA buffer with fd %d\n", fd);
> +
> + attach = gntdev_dmabuf->u.imp.attach;
> +
> + if (gntdev_dmabuf->u.imp.sgt)
> + dma_buf_unmap_attachment(attach, gntdev_dmabuf->u.imp.sgt,
> + DMA_BIDIRECTIONAL);
> + dma_buf = attach->dmabuf;
> + dma_buf_detach(attach->dmabuf, attach);
> + dma_buf_put(dma_buf);
> +
> + dmabuf_imp_end_foreign_access(gntdev_dmabuf->u.imp.refs,
> + gntdev_dmabuf->nr_pages);

Should you first end foreign access, before doing anything?

-boris

> + dmabuf_imp_free_storage(gntdev_dmabuf);
> + return 0;
> }
>