diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/pipe_fs_i.h | 29 |
1 files changed, 25 insertions, 4 deletions
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h index 0008d4bd405..df4d3fa7d3d 100644 --- a/include/linux/pipe_fs_i.h +++ b/include/linux/pipe_fs_i.h @@ -5,8 +5,9 @@ #define PIPE_BUFFERS (16) -#define PIPE_BUF_FLAG_STOLEN 0x01 -#define PIPE_BUF_FLAG_LRU 0x02 +#define PIPE_BUF_FLAG_LRU 0x01 /* page is on the LRU */ +#define PIPE_BUF_FLAG_ATOMIC 0x02 /* was atomically mapped */ +#define PIPE_BUF_FLAG_GIFT 0x04 /* page is a gift */ struct pipe_buffer { struct page *page; @@ -15,10 +16,23 @@ struct pipe_buffer { unsigned int flags; }; +/* + * Note on the nesting of these functions: + * + * ->pin() + * ->steal() + * ... + * ->map() + * ... + * ->unmap() + * + * That is, ->map() must be called on a pinned buffer, same goes for ->steal(). + */ struct pipe_buf_operations { int can_merge; - void * (*map)(struct file *, struct pipe_inode_info *, struct pipe_buffer *); - void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *); + void * (*map)(struct pipe_inode_info *, struct pipe_buffer *, int); + void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *, void *); + int (*pin)(struct pipe_inode_info *, struct pipe_buffer *); void (*release)(struct pipe_inode_info *, struct pipe_buffer *); int (*steal)(struct pipe_inode_info *, struct pipe_buffer *); void (*get)(struct pipe_inode_info *, struct pipe_buffer *); @@ -51,6 +65,12 @@ struct pipe_inode_info * alloc_pipe_info(struct inode * inode); void free_pipe_info(struct inode * inode); void __free_pipe_info(struct pipe_inode_info *); +/* Generic pipe buffer ops functions */ +void *generic_pipe_buf_map(struct pipe_inode_info *, struct pipe_buffer *, int); +void generic_pipe_buf_unmap(struct pipe_inode_info *, struct pipe_buffer *, void *); +void generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *); +int generic_pipe_buf_pin(struct pipe_inode_info *, struct pipe_buffer *); + /* * splice is tied to pipes as a transport (at least for now), so we'll just * add the splice flags here. @@ -60,6 +80,7 @@ void __free_pipe_info(struct pipe_inode_info *); /* we may still block on the fd we splice */ /* from/to, of course */ #define SPLICE_F_MORE (0x04) /* expect more data */ +#define SPLICE_F_GIFT (0x08) /* pages passed in are a gift */ /* * Passed to the actors |