From 9f90381b3ec8ad5056348642333f0220c95def27 Mon Sep 17 00:00:00 2001 From: Rohit kumar Date: Tue, 12 Jan 2016 09:31:46 +0530 Subject: [PATCH] staging/ion: Add support to get ion handle from dma buf 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 Reviewed-by: Sumit Semwal Signed-off-by: Greg Kroah-Hartman --- drivers/staging/android/ion/ion.c | 26 ++++++++++++++++++-------- drivers/staging/android/ion/ion.h | 20 ++++++++++++++++---- 2 files changed, 34 insertions(+), 12 deletions(-) diff --git a/drivers/staging/android/ion/ion.c b/drivers/staging/android/ion/ion.c index df560216d702..d6698483e152 100644 --- a/drivers/staging/android/ion/ion.c +++ b/drivers/staging/android/ion/ion.c @@ -1153,22 +1153,18 @@ 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) { pr_err("%s: can not import dmabuf from another exporter\n", __func__); - dma_buf_put(dmabuf); return ERR_PTR(-EINVAL); } buffer = dmabuf->priv; @@ -1196,11 +1192,25 @@ struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd) } end: - dma_buf_put(dmabuf); return handle; } EXPORT_SYMBOL(ion_import_dma_buf); +struct ion_handle *ion_import_dma_buf_fd(struct ion_client *client, int fd) +{ + struct dma_buf *dmabuf; + struct ion_handle *handle; + + dmabuf = dma_buf_get(fd); + if (IS_ERR(dmabuf)) + return ERR_CAST(dmabuf); + + handle = ion_import_dma_buf(client, dmabuf); + dma_buf_put(dmabuf); + return handle; +} +EXPORT_SYMBOL(ion_import_dma_buf_fd); + static int ion_sync_for_device(struct ion_client *client, int fd) { struct dma_buf *dmabuf; @@ -1308,7 +1318,7 @@ 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 b860c5f579f5..a1331fc169a1 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 */ -- 2.20.1