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/*
* Header file for dma buffer sharing framework.
*
* Copyright(C) 2011 Linaro Limited. All rights reserved.
* Author: Sumit Semwal <sumit.semwal@ti.com>
*
* Many thanks to linaro-mm-sig list, and specially
* Arnd Bergmann <arnd@arndb.de>, Rob Clark <rob@ti.com> and
* Daniel Vetter <daniel@ffwll.ch> for their support in creation and
* refining of this idea.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along with
* this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __DMA_BUF_H__
#define __DMA_BUF_H__
#include <linux/file.h>
#include <linux/err.h>
#include <linux/scatterlist.h>
#include <linux/list.h>
#include <linux/dma-mapping.h>
#include <linux/fs.h>
struct device;
struct dma_buf;
struct dma_buf_attachment;
struct dma_buf_ops {
int (*attach)(struct dma_buf *, struct device *,
struct dma_buf_attachment *);
void (*detach)(struct dma_buf *, struct dma_buf_attachment *);
struct sg_table * (*map_dma_buf)(struct dma_buf_attachment *,
enum dma_data_direction);
void (*unmap_dma_buf)(struct dma_buf_attachment *,
struct sg_table *,
enum dma_data_direction);
void (*release)(struct dma_buf *);
int (*begin_cpu_access)(struct dma_buf *, size_t, size_t,
enum dma_data_direction);
void (*end_cpu_access)(struct dma_buf *, size_t, size_t,
enum dma_data_direction);
void *(*kmap_atomic)(struct dma_buf *, unsigned long);
void (*kunmap_atomic)(struct dma_buf *, unsigned long, void *);
void *(*kmap)(struct dma_buf *, unsigned long);
void (*kunmap)(struct dma_buf *, unsigned long, void *);
int (*mmap)(struct dma_buf *, struct vm_area_struct *vma);
};
struct dma_buf {
size_t size;
struct file *file;
struct list_head attachments;
const struct dma_buf_ops *ops;
struct mutex lock;
void *priv;
};
struct dma_buf_attachment {
struct dma_buf *dmabuf;
struct device *dev;
struct list_head node;
void *priv;
};
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);
void dma_buf_detach(struct dma_buf *dmabuf,
struct dma_buf_attachment *dmabuf_attach);
struct dma_buf *dma_buf_export(void *priv, const struct dma_buf_ops *ops,
size_t size, int flags);
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);
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 *,
enum dma_data_direction);
int dma_buf_begin_cpu_access(struct dma_buf *dma_buf, size_t start, size_t len,
enum dma_data_direction dir);
void dma_buf_end_cpu_access(struct dma_buf *dma_buf, size_t start, size_t len,
enum dma_data_direction dir);
void *dma_buf_kmap_atomic(struct dma_buf *, unsigned long);
void dma_buf_kunmap_atomic(struct dma_buf *, unsigned long, void *);
void *dma_buf_kmap(struct dma_buf *, unsigned long);
void dma_buf_kunmap(struct dma_buf *, unsigned long, void *);
int dma_buf_mmap(struct dma_buf *, struct vm_area_struct *,
unsigned long);
#else
static inline struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf,
struct device *dev)
{
return ERR_PTR(-ENODEV);
}
static inline void dma_buf_detach(struct dma_buf *dmabuf,
struct dma_buf_attachment *dmabuf_attach)
{
return;
}
static inline struct dma_buf *dma_buf_export(void *priv,
const struct dma_buf_ops *ops,
size_t size, int flags)
{
return ERR_PTR(-ENODEV);
}
static inline int dma_buf_fd(struct dma_buf *dmabuf, int flags)
{
return -ENODEV;
}
static inline struct dma_buf *dma_buf_get(int fd)
{
return ERR_PTR(-ENODEV);
}
static inline void dma_buf_put(struct dma_buf *dmabuf)
{
return;
}
static inline struct sg_table *dma_buf_map_attachment(
struct dma_buf_attachment *attach, enum dma_data_direction write)
{
return ERR_PTR(-ENODEV);
}
static inline void dma_buf_unmap_attachment(struct dma_buf_attachment *attach,
struct sg_table *sg, enum dma_data_direction dir)
{
return;
}
static inline int dma_buf_begin_cpu_access(struct dma_buf *dmabuf,
size_t start, size_t len,
enum dma_data_direction dir)
{
return -ENODEV;
}
static inline void dma_buf_end_cpu_access(struct dma_buf *dmabuf,
size_t start, size_t len,
enum dma_data_direction dir)
{
}
static inline void *dma_buf_kmap_atomic(struct dma_buf *dmabuf,
unsigned long pnum)
{
return NULL;
}
static inline void dma_buf_kunmap_atomic(struct dma_buf *dmabuf,
unsigned long pnum, void *vaddr)
{
}
static inline void *dma_buf_kmap(struct dma_buf *dmabuf, unsigned long pnum)
{
return NULL;
}
static inline void dma_buf_kunmap(struct dma_buf *dmabuf,
unsigned long pnum, void *vaddr)
{
}
static inline int dma_buf_mmap(struct dma_buf *dmabuf,
struct vm_area_struct *vma,
unsigned long pgoff)
{
return -ENODEV;
}
#endif
#endif
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