fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / include / linux / pipe_fs_i.h

diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 407c0e0..2e19478 100644 (file)
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -2,11 +2,46 @@
 #define _LINUX_PIPE_FS_I_H
 
 #define PIPEFS_MAGIC 0x50495045
+
+#define PIPE_BUFFERS (16)
+
+#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;
+       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 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;
-       char *base;
-       unsigned int len;
-       unsigned int start;
+       unsigned int nrbufs, curbuf;
+       struct page *tmp_page;
        unsigned int readers;
        unsigned int writers;
        unsigned int waiting_writers;
@@ -14,35 +49,54 @@ struct pipe_inode_info {
        unsigned int w_counter;
        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
    memory allocation, whereas PIPE_BUF makes atomicity guarantees.  */
 #define PIPE_SIZE              PAGE_SIZE
 
-#define PIPE_SEM(inode)                (&(inode).i_sem)
-#define PIPE_WAIT(inode)       (&(inode).i_pipe->wait)
-#define PIPE_BASE(inode)       ((inode).i_pipe->base)
-#define PIPE_START(inode)      ((inode).i_pipe->start)
-#define PIPE_LEN(inode)                ((inode).i_pipe->len)
-#define PIPE_READERS(inode)    ((inode).i_pipe->readers)
-#define PIPE_WRITERS(inode)    ((inode).i_pipe->writers)
-#define PIPE_WAITING_WRITERS(inode)    ((inode).i_pipe->waiting_writers)
-#define PIPE_RCOUNTER(inode)   ((inode).i_pipe->r_counter)
-#define PIPE_WCOUNTER(inode)   ((inode).i_pipe->w_counter)
-#define PIPE_FASYNC_READERS(inode)     (&((inode).i_pipe->fasync_readers))
-#define PIPE_FASYNC_WRITERS(inode)     (&((inode).i_pipe->fasync_writers))
-
-#define PIPE_EMPTY(inode)      (PIPE_LEN(inode) == 0)
-#define PIPE_FULL(inode)       (PIPE_LEN(inode) == PIPE_SIZE)
-#define PIPE_FREE(inode)       (PIPE_SIZE - PIPE_LEN(inode))
-#define PIPE_END(inode)        ((PIPE_START(inode) + PIPE_LEN(inode)) & (PIPE_SIZE-1))
-#define PIPE_MAX_RCHUNK(inode) (PIPE_SIZE - PIPE_START(inode))
-#define PIPE_MAX_WCHUNK(inode) (PIPE_SIZE - PIPE_END(inode))
-
 /* Drop the inode semaphore and wait for a pipe event, atomically */
-void pipe_wait(struct inode * inode);
+void pipe_wait(struct pipe_inode_info *pipe);
+
+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 *);
+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.
+ */
+#define SPLICE_F_MOVE  (0x01)  /* move pages instead of copying */
+#define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */
+                                /* 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
+ */
+struct splice_desc {
+       unsigned int len, total_len;    /* current and remaining length */
+       unsigned int flags;             /* splice flags */
+       struct file *file;              /* file to read/write */
+       loff_t pos;                     /* file position */
+};
+
+typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
+                          struct splice_desc *);
 
-struct inode* pipe_new(struct inode* inode);
+extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
+                               loff_t *, size_t, unsigned int,
+                               splice_actor *);
 
 #endif