From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752509AbcAFS1A (ORCPT ); Wed, 6 Jan 2016 13:27:00 -0500 Received: from mx1.redhat.com ([209.132.183.28]:49618 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751998AbcAFS05 (ORCPT ); Wed, 6 Jan 2016 13:26:57 -0500 Subject: Re: [PATCHv2 1/1] staging/ion: Add support to get ion handle from dma buf To: Rohit kumar , gregkh@linuxfoundation.org, arve@android.com, riandrews@android.com, dan.carpenter@oracle.com, gioh.kim@lge.com, sumit.semwal@linaro.org, mitchelh@codeaurora.org, paul.gortmaker@windriver.com, linux@rasmusvillemoes.dk, shawn.lin@rock-chips.com, sriram@marirs.net.in, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org, pintu.k@samsung.com, vishnu.ps@samsung.com References: <1451998982-15654-1-git-send-email-rohit.kr@samsung.com> <1452064269-18601-1-git-send-email-rohit.kr@samsung.com> Cc: sreenathd@samsung.com, pintu_agarwal@yahoo.com, me.rohit@live.com, cpgs@samsung.com From: Laura Abbott Message-ID: <568D5C6C.1060807@redhat.com> Date: Wed, 6 Jan 2016 10:26:52 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <1452064269-18601-1-git-send-email-rohit.kr@samsung.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/05/2016 11:11 PM, Rohit kumar wrote: > Currently we can only import dma buf fd's to get ion_handle. > Adding support to import dma buf handles to support kernel > specific use cases. > > An example use case is in linux platforms such as Tizen, in which > DRM-GEM is used for buffer management for graphics. It has gem_handle > corresponding to a buffer and uses gem_name for sharing the buffer > with other processes. However,it also uses dma_buf fd for 3d operations. > For wayland, there are multiple calls for gem_handle to dma_buf fd > conversion. So, we store dma_buf associated with buffer. But, there is > no api for getting ion_handle from dma_buf. This patch exposes api to > retrieve the ion handle from dma_buf for similar use cases. With this > patch, we can integrate ION within DRM-GEM for buffer management and > dma_buf sharing. > > Signed-off-by: Rohit kumar Reviewed-by: Laura Abbott > --- > v2: Updated commit message with use case explanation, as suggested by > Laura Abbott > > drivers/staging/android/ion/ion.c | 21 +++++++++++++++------ > drivers/staging/android/ion/ion.h | 20 ++++++++++++++++---- > 2 files changed, 31 insertions(+), 10 deletions(-) > > diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c > index e237e9f..5509716 100644 > --- a/drivers/staging/android/ion/ion.c > +++ b/drivers/staging/android/ion/ion.c > @@ -1151,16 +1151,13 @@ int ion_share_dma_buf_fd(struct ion_client *client, struct ion_handle *handle) > } > EXPORT_SYMBOL(ion_share_dma_buf_fd); > > -struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd) > +struct ion_handle *ion_import_dma_buf(struct ion_client *client, > + struct dma_buf *dmabuf) > { > - struct dma_buf *dmabuf; > struct ion_buffer *buffer; > struct ion_handle *handle; > int ret; > > - dmabuf = dma_buf_get(fd); > - if (IS_ERR(dmabuf)) > - return ERR_CAST(dmabuf); > /* if this memory came from ion */ > > if (dmabuf->ops != &dma_buf_ops) { > @@ -1199,6 +1196,18 @@ end: > } > EXPORT_SYMBOL(ion_import_dma_buf); > > +struct ion_handle *ion_import_dma_buf_fd(struct ion_client *client, int fd) > +{ > + struct dma_buf *dmabuf; > + > + dmabuf = dma_buf_get(fd); > + if (IS_ERR(dmabuf)) > + return ERR_CAST(dmabuf); > + > + return ion_import_dma_buf(client, dmabuf); > +} > +EXPORT_SYMBOL(ion_import_dma_buf_fd); > + > static int ion_sync_for_device(struct ion_client *client, int fd) > { > struct dma_buf *dmabuf; > @@ -1306,7 +1315,7 @@ static long ion_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) > { > struct ion_handle *handle; > > - handle = ion_import_dma_buf(client, data.fd.fd); > + handle = ion_import_dma_buf_fd(client, data.fd.fd); > if (IS_ERR(handle)) > ret = PTR_ERR(handle); > else > diff --git a/drivers/staging/android/ion/ion.h b/drivers/staging/android/ion/ion.h > index b860c5f..a1331fc 100644 > --- a/drivers/staging/android/ion/ion.h > +++ b/drivers/staging/android/ion/ion.h > @@ -192,14 +192,26 @@ struct dma_buf *ion_share_dma_buf(struct ion_client *client, > int ion_share_dma_buf_fd(struct ion_client *client, struct ion_handle *handle); > > /** > - * ion_import_dma_buf() - given an dma-buf fd from the ion exporter get handle > + * ion_import_dma_buf() - get ion_handle from dma-buf > + * @client: the client > + * @dmabuf: the dma-buf > + * > + * Get the ion_buffer associated with the dma-buf and return the ion_handle. > + * If no ion_handle exists for this buffer, return newly created ion_handle. > + * If dma-buf from another exporter is passed, return ERR_PTR(-EINVAL) > + */ > +struct ion_handle *ion_import_dma_buf(struct ion_client *client, > + struct dma_buf *dmabuf); > + > +/** > + * ion_import_dma_buf_fd() - given a dma-buf fd from the ion exporter get handle > * @client: the client > * @fd: the dma-buf fd > * > - * Given an dma-buf fd that was allocated through ion via ion_share_dma_buf, > - * import that fd and return a handle representing it. If a dma-buf from > + * Given an dma-buf fd that was allocated through ion via ion_share_dma_buf_fd, > + * import that fd and return a handle representing it. If a dma-buf from > * another exporter is passed in this function will return ERR_PTR(-EINVAL) > */ > -struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd); > +struct ion_handle *ion_import_dma_buf_fd(struct ion_client *client, int fd); > > #endif /* _LINUX_ION_H */ >