splice: abstract out actor data

For direct splicing (or private splicing), the output may not be a file.
So abstract out the handling into a specified actor function and put
the data in the splice_desc structure earlier, so we can build on top
of that.

This is the first step in better splice handling for drivers, and also
for implementing vmsplice _to_ user memory.

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

1 files changed, 8 insertions, 3 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index ac6c964..93565c0 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1636,9 +1636,14 @@ static ssize_t __ocfs2_file_splice_write(struct pipe_inode_info *pipe,
 	int ret, err;
 	struct address_space *mapping = out->f_mapping;
 	struct inode *inode = mapping->host;
-
-	ret = __splice_from_pipe(pipe, out, ppos, len, flags,
-				 ocfs2_splice_write_actor);
+	struct splice_desc sd = {
+		.total_len = len,
+		.flags = flags,
+		.pos = *ppos,
+		.file = out,
+	};
+
+	ret = __splice_from_pipe(pipe, &sd, ocfs2_splice_write_actor);
 	if (ret > 0) {
 		*ppos += ret;