NFS: remove nfs_inode radix tree

The radix tree is only being used to compile lists of reqs needing commit.
It is simpler to just put the reqs directly into a list.

Signed-off-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_fs.h b/include/linux/nfs_fs.h
index ce8e436..0a63ab2 100644
--- a/include/linux/nfs_fs.h
+++ b/include/linux/nfs_fs.h
@@ -171,13 +171,9 @@
 	 */
 	__be32			cookieverf[2];
 
-	/*
-	 * This is the list of dirty unwritten pages.
-	 */
-	struct radix_tree_root	nfs_page_tree;
-
 	unsigned long		npages;
 	unsigned long		ncommit;
+	struct list_head	commit_list;
 
 	/* Open contexts for shared mmap writes */
 	struct list_head	open_files;