NFSv4.1: file layout must consider pg_bsize for coalescing

Otherwise we end up overflowing the rpc buffer size on the receive end.

Signed-off-by: Benny Halevy <benny@tonian.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 5d6f369..0bafcc9 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -30,6 +30,7 @@
  */
 
 #include <linux/nfs_fs.h>
+#include <linux/nfs_page.h>
 
 #include "internal.h"
 #include "nfs4filelayout.h"
@@ -666,8 +667,9 @@
 	u64 p_stripe, r_stripe;
 	u32 stripe_unit;
 
-	if (!pnfs_generic_pg_test(pgio, prev, req))
-		return 0;
+	if (!pnfs_generic_pg_test(pgio, prev, req) ||
+	    !nfs_generic_pg_test(pgio, prev, req))
+		return false;
 
 	if (!pgio->pg_lseg)
 		return 1;
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 7913961..0098557 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -204,7 +204,7 @@
 			TASK_UNINTERRUPTIBLE);
 }
 
-static bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req)
+bool nfs_generic_pg_test(struct nfs_pageio_descriptor *desc, struct nfs_page *prev, struct nfs_page *req)
 {
 	/*
 	 * FIXME: ideally we should be able to coalesce all requests
@@ -218,6 +218,7 @@
 
 	return desc->pg_count + req->wb_bytes <= desc->pg_bsize;
 }
+EXPORT_SYMBOL_GPL(nfs_generic_pg_test);
 
 /**
  * nfs_pageio_init - initialise a page io descriptor