diff options
| author | Arto Merilainen <amerilainen@nvidia.com> | 2014-02-16 15:22:50 +0200 |
|---|---|---|
| committer | Terje Bergstrom <tbergstrom@nvidia.com> | 2014-02-26 22:35:21 -0800 |
| commit | a5757cc67b0e151475101bf451df9fc092816a46 (patch) | |
| tree | d7033827c82471e34df67d1ef447a1e0c47d846d | |
| parent | b9de88f6b2362532edbab617fd2d824b83fcf059 (diff) | |
dmabuf: Support driver data
Occassionally we need to store driver/device specific data of a device
that survives over attach/detach sequence. This patch adds support for
defining drvdata inside dmabuf.
Bug 1450489
Change-Id: I840d415657a07ef86476e32bcac4e13a8706ece4
Signed-off-by: Arto Merilainen <amerilainen@nvidia.com>
Reviewed-on: http://git-master/r/368139
Reviewed-by: Krishna Reddy <vdumpa@nvidia.com>
Reviewed-by: Terje Bergstrom <tbergstrom@nvidia.com>
| -rw-r--r-- | drivers/base/dma-buf.c | 50 | ||||
| -rw-r--r-- | include/linux/dma-buf.h | 8 |
2 files changed, 58 insertions, 0 deletions
diff --git a/drivers/base/dma-buf.c b/drivers/base/dma-buf.c index 08fe897c0b4c..f98d1ad2ded7 100644 --- a/drivers/base/dma-buf.c +++ b/drivers/base/dma-buf.c @@ -39,6 +39,56 @@ struct dma_buf_list { static struct dma_buf_list db_list; +/** + * dma_buf_set_drvdata - Set driver specific data to dmabuf. The data + * will remain even if the device is detached from the device. This is useful + * if the device requires some buffer specific parameters that should be + * available when the buffer is accessed next time. + * + * The exporter calls the destroy callback: + * - the buffer is freed + * - the device/driver is removed + * - new device private data is set + * + * @dmabuf [in] Buffer object + * @device [in] Device to which the data is related to. + * @priv [in] Private data + * @destroy [in] Function callback to destroy function. Called when the + * data is not needed anymore (device or dmabuf is + * removed) + * + * The function returns 0 on success. Otherwise the function returns a negative + * errorcode + */ +int dma_buf_set_drvdata(struct dma_buf * dmabuf, struct device *device, + void *priv, void (*destroy)(void *)) +{ + if (!(dmabuf && dmabuf->ops && dmabuf->ops->set_drvdata)) + return -ENOSYS; + + return dmabuf->ops->set_drvdata(dmabuf, device, priv, destroy); +} +EXPORT_SYMBOL(dma_buf_set_drvdata); + +/** + * dma_buf_get_drvdata - Get driver specific data to dmabuf. + * + * @dmabuf [in] Buffer object + * @device [in] Device to which the data is related to. + * + * The function returns the user data structure on success. Otherwise NULL + * is returned. + */ +void *dma_buf_get_drvdata(struct dma_buf *dmabuf, struct device *device) +{ + if (!(dmabuf && dmabuf->ops && dmabuf->ops->get_drvdata)) + return ERR_PTR(-ENOSYS); + + return dmabuf->ops->get_drvdata(dmabuf, device); +} +EXPORT_SYMBOL(dma_buf_get_drvdata); + + static int dma_buf_release(struct inode *inode, struct file *file) { struct dma_buf *dmabuf; diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index dfac5ed31120..cf1f03f69a47 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -104,6 +104,10 @@ struct dma_buf_ops { void *(*vmap)(struct dma_buf *); void (*vunmap)(struct dma_buf *, void *vaddr); + + void *(*get_drvdata)(struct dma_buf *, struct device *); + int (*set_drvdata)(struct dma_buf *, struct device *, void *priv, + void (*)(void *)); }; /** @@ -177,6 +181,10 @@ int dma_buf_fd(struct dma_buf *dmabuf, int flags); struct dma_buf *dma_buf_get(int fd); void dma_buf_put(struct dma_buf *dmabuf); +int dma_buf_set_drvdata(struct dma_buf *, struct device *, + void *, void (*destroy)(void *)); +void *dma_buf_get_drvdata(struct dma_buf *, struct device *); + struct sg_table *dma_buf_map_attachment(struct dma_buf_attachment *, enum dma_data_direction); void dma_buf_unmap_attachment(struct dma_buf_attachment *, struct sg_table *, |