splice: divorce the splice structure/function definitions from the pipe header

We need to move even more stuff into the header so that folks can use
the splice_to_pipe() implementation instead of open-coding a lot of
pipe knowledge (see relay implementation), so move to our own header
file finally.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

9 files changed, 83 insertions, 68 deletions

diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 87d84e7d5432..08f53df03e8c 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -74,7 +74,7 @@
 #include <linux/highmem.h>
 #include <linux/gfp.h>
 #include <linux/kthread.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 
 #include <asm/uaccess.h>
 
diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index cc9a9d0df979..d2e4cfd79f27 100644
--- a/drivers/char/mem.c
+++ b/drivers/char/mem.c
@@ -24,7 +24,7 @@
 #include <linux/crash_dump.h>
 #include <linux/backing-dev.h>
 #include <linux/bootmem.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 #include <linux/pfn.h>
 
 #include <asm/uaccess.h>
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 15471a9efe0e..8176fbf5c006 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -23,7 +23,7 @@
 #include <linux/file.h>
 #include <linux/mount.h>
 #include <linux/major.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 #include <linux/proc_fs.h>
 #include <linux/stat.h>
 #include <linux/fcntl.h>
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index ed1ffa70cc38..44c2e2afa465 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -31,7 +31,7 @@
 #include <linux/pagemap.h>
 #include <linux/uio.h>
 #include <linux/sched.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 #include <linux/mount.h>
 #include <linux/writeback.h>
 
diff --git a/fs/read_write.c b/fs/read_write.c
index 47da8a4a0fbe..2527cf035b0e 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -15,7 +15,7 @@
 #include <linux/module.h>
 #include <linux/syscalls.h>
 #include <linux/pagemap.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 #include "read_write.h"
 
 #include <asm/uaccess.h>
diff --git a/fs/splice.c b/fs/splice.c
index 13846f723d72..bea9f1581ca0 100644
--- a/fs/splice.c
+++ b/fs/splice.c
@@ -20,7 +20,7 @@
 #include <linux/fs.h>
 #include <linux/file.h>
 #include <linux/pagemap.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 #include <linux/mm_inline.h>
 #include <linux/swap.h>
 #include <linux/writeback.h>
@@ -29,22 +29,6 @@
 #include <linux/syscalls.h>
 #include <linux/uio.h>
 
-struct partial_page {
-        unsigned int offset;
-        unsigned int len;
-};
-
-/*
- * Passed to splice_to_pipe
- */
-struct splice_pipe_desc {
-        struct page **pages;            /* page map */
-        struct partial_page *partial;   /* pages[] may not be contig */
-        int nr_pages;                   /* number of pages in map */
-        unsigned int flags;             /* splice flags */
-        const struct pipe_buf_operations *ops;/* ops associated with output pipe */
-};
-
 /*
  * Attempt to steal a page from a pipe buffer. This should perhaps go into
  * a vm helper function, it's already simplified quite a bit by the
@@ -170,11 +154,11 @@ static const struct pipe_buf_operations user_page_pipe_buf_ops = {
 };
 
 /*
- * Pipe output worker. This sets up our pipe format with the page cache
- * pipe buffer operations. Otherwise very similar to the regular pipe_writev().
+ * Pipe output worker. This fills a pipe with the information contained
+ * from splice_pipe_desc().
  */
-static ssize_t splice_to_pipe(struct pipe_inode_info *pipe,
-                              struct splice_pipe_desc *spd)
+ssize_t splice_to_pipe(struct pipe_inode_info *pipe,
+                       struct splice_pipe_desc *spd)
 {
         unsigned int spd_pages = spd->nr_pages;
         int ret, do_wakeup, page_nr;
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index f277a9cdb50d..7ba228d52f58 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -71,45 +71,4 @@ 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 */
-        /*
-         * actor() private data
-         */
-        union {
-                void __user *userptr;   /* memory to write to */
-                struct file *file;      /* file to read/write */
-                void *data;             /* cookie */
-        } u;
-        loff_t pos;                     /* file position */
-};
-
-typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
-                           struct splice_desc *);
-typedef int (splice_direct_actor)(struct pipe_inode_info *,
-                                  struct splice_desc *);
-
-extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
-                                loff_t *, size_t, unsigned int,
-                                splice_actor *);
-extern ssize_t __splice_from_pipe(struct pipe_inode_info *,
-                                  struct splice_desc *, splice_actor *);
-extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
-                                      splice_direct_actor *);
-
 #endif
diff --git a/include/linux/splice.h b/include/linux/splice.h
new file mode 100644
index 000000000000..f8cc97f71cd0
--- /dev/null
+++ b/include/linux/splice.h
@@ -0,0 +1,72 @@
+/*
+ * Function declerations and data structures related to the splice
+ * implementation.
+ *
+ * Copyright (C) 2007 Jens Axboe <jens.axboe@oracle.com>
+ *
+ */
+#ifndef SPLICE_H
+#define SPLICE_H
+
+#include <linux/pipe_fs_i.h>
+
+/*
+ * 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 */
+        /*
+         * actor() private data
+         */
+        union {
+                void __user *userptr;   /* memory to write to */
+                struct file *file;      /* file to read/write */
+                void *data;             /* cookie */
+        } u;
+        loff_t pos;                     /* file position */
+};
+
+struct partial_page {
+        unsigned int offset;
+        unsigned int len;
+};
+
+/*
+ * Passed to splice_to_pipe
+ */
+struct splice_pipe_desc {
+        struct page **pages;            /* page map */
+        struct partial_page *partial;   /* pages[] may not be contig */
+        int nr_pages;                   /* number of pages in map */
+        unsigned int flags;             /* splice flags */
+        const struct pipe_buf_operations *ops;/* ops associated with output pipe */
+};
+
+typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
+                           struct splice_desc *);
+typedef int (splice_direct_actor)(struct pipe_inode_info *,
+                                  struct splice_desc *);
+
+extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
+                                loff_t *, size_t, unsigned int,
+                                splice_actor *);
+extern ssize_t __splice_from_pipe(struct pipe_inode_info *,
+                                  struct splice_desc *, splice_actor *);
+extern ssize_t splice_to_pipe(struct pipe_inode_info *,
+                              struct splice_pipe_desc *);
+extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *,
+                                      splice_direct_actor *);
+
+#endif
diff --git a/kernel/relay.c b/kernel/relay.c
index d1d1920f2800..951f29b24e58 100644
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -21,7 +21,7 @@
 #include <linux/vmalloc.h>
 #include <linux/mm.h>
 #include <linux/cpu.h>
-#include <linux/pipe_fs_i.h>
+#include <linux/splice.h>
 
 /* list of open channels, for cpu hotplug */
 static DEFINE_MUTEX(relay_channels_mutex);