pnfs: pass ds_commit_idx through the commit path

Pass ds_commit_idx through the nfs commit path. It's used to select
the commit bucket when using pnfs and is ignored when not using pnfs.
Several functions had to be changed: nfs_retry_commit,
nfs_mark_request_commit, pnfs_mark_request_commit and the pnfs layout
driver .mark_request_commit functions.

Signed-off-by: Tom Haynes <loghyr@primarydata.com>
diff --git a/fs/nfs/filelayout/filelayout.c b/fs/nfs/filelayout/filelayout.c
index 520cbc5..3c97694 100644
--- a/fs/nfs/filelayout/filelayout.c
+++ b/fs/nfs/filelayout/filelayout.c
@@ -954,7 +954,8 @@
 static void
 filelayout_mark_request_commit(struct nfs_page *req,
 			       struct pnfs_layout_segment *lseg,
-			       struct nfs_commit_info *cinfo)
+			       struct nfs_commit_info *cinfo,
+			       u32 ds_commit_idx)
 
 {
 	struct nfs4_filelayout_segment *fl = FILELAYOUT_LSEG(lseg);