truncate: drop 'oldsize' truncate_pagecache() parameter

truncate_pagecache() doesn't care about old size since commit
cedabed49b39 ("vfs: Fix vmtruncate() regression").  Let's drop it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/nfs/inode.c b/fs/nfs/inode.c
index 87e7976..eda8879 100644
--- a/fs/nfs/inode.c
+++ b/fs/nfs/inode.c
@@ -541,7 +541,6 @@
  */
 static int nfs_vmtruncate(struct inode * inode, loff_t offset)
 {
-	loff_t oldsize;
 	int err;
 
 	err = inode_newsize_ok(inode, offset);
@@ -549,11 +548,10 @@
 		goto out;
 
 	spin_lock(&inode->i_lock);
-	oldsize = inode->i_size;
 	i_size_write(inode, offset);
 	spin_unlock(&inode->i_lock);
 
-	truncate_pagecache(inode, oldsize, offset);
+	truncate_pagecache(inode, offset);
 out:
 	return err;
 }