diff options
Diffstat (limited to 'include/linux/dma-buf.h')
| -rw-r--r-- | include/linux/dma-buf.h | 99 |
1 files changed, 88 insertions, 11 deletions
diff --git a/include/linux/dma-buf.h b/include/linux/dma-buf.h index f8ac076afa52..3efbfc2145c3 100644 --- a/include/linux/dma-buf.h +++ b/include/linux/dma-buf.h @@ -26,11 +26,12 @@ #include <linux/file.h> #include <linux/err.h> -#include <linux/device.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; @@ -49,6 +50,17 @@ struct dma_buf_attachment; * @unmap_dma_buf: decreases usecount of buffer, might deallocate scatter * pages. * @release: release this buffer; to be called after the last dma_buf_put. + * @begin_cpu_access: [optional] called before cpu access to invalidate cpu + * caches and allocate backing storage (if not yet done) + * respectively pin the objet into memory. + * @end_cpu_access: [optional] called after cpu access to flush cashes. + * @kmap_atomic: maps a page from the buffer into kernel address + * space, users may not block until the subsequent unmap call. + * This callback must not sleep. + * @kunmap_atomic: [optional] unmaps a atomically mapped page from the buffer. + * This Callback must not sleep. + * @kmap: maps a page from the buffer into kernel address space. + * @kunmap: [optional] unmaps a page from the buffer. */ struct dma_buf_ops { int (*attach)(struct dma_buf *, struct device *, @@ -63,7 +75,8 @@ struct dma_buf_ops { 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 *); + struct sg_table *, + enum dma_data_direction); /* TODO: Add try_map_dma_buf version, to return immed with -EBUSY * if the call would block. */ @@ -71,6 +84,14 @@ struct dma_buf_ops { /* after final dma_buf_put() */ 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 *); }; /** @@ -86,7 +107,7 @@ struct dma_buf { struct file *file; struct list_head attachments; const struct dma_buf_ops *ops; - /* mutex to serialize list manipulation and other ops */ + /* mutex to serialize list manipulation and attach/detach */ struct mutex lock; void *priv; }; @@ -109,20 +130,43 @@ struct dma_buf_attachment { void *priv; }; +/** + * get_dma_buf - convenience wrapper for get_file. + * @dmabuf: [in] pointer to dma_buf + * + * Increments the reference count on the dma-buf, needed in case of drivers + * that either need to create additional references to the dmabuf on the + * kernel side. For example, an exporter that needs to keep a dmabuf ptr + * so that subsequent exports don't create a new dmabuf. + */ +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, struct dma_buf_ops *ops, - size_t size, int flags); -int dma_buf_fd(struct dma_buf *dmabuf); +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 *); +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 *); #else static inline struct dma_buf_attachment *dma_buf_attach(struct dma_buf *dmabuf, @@ -138,13 +182,13 @@ static inline void dma_buf_detach(struct dma_buf *dmabuf, } static inline struct dma_buf *dma_buf_export(void *priv, - struct dma_buf_ops *ops, - size_t size, int flags) + 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) +static inline int dma_buf_fd(struct dma_buf *dmabuf, int flags) { return -ENODEV; } @@ -166,11 +210,44 @@ static inline struct sg_table *dma_buf_map_attachment( } static inline void dma_buf_unmap_attachment(struct dma_buf_attachment *attach, - struct sg_table *sg) + 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) +{ +} #endif /* CONFIG_DMA_SHARED_BUFFER */ #endif /* __DMA_BUF_H__ */ |