#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;
unsigned int offset, len;
- struct pipe_buf_operations *ops;
+ const struct pipe_buf_operations *ops;
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 *);
struct pipe_inode_info {
wait_queue_head_t wait;
unsigned int nrbufs, curbuf;
- struct pipe_buffer bufs[PIPE_BUFFERS];
struct page *tmp_page;
- unsigned int start;
unsigned int readers;
unsigned int writers;
unsigned int waiting_writers;
struct fasync_struct *fasync_readers;
struct fasync_struct *fasync_writers;
struct inode *inode;
+ struct pipe_buffer bufs[PIPE_BUFFERS];
};
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
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 *);
+int generic_pipe_buf_steal(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.
/* 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
loff_t *, size_t, unsigned int,
splice_actor *);
+extern ssize_t __splice_from_pipe(struct pipe_inode_info *, struct file *,
+ loff_t *, size_t, unsigned int,
+ splice_actor *);
+
#endif