new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ramfs/file-nommu.c b/fs/ramfs/file-nommu.c
index d5378d0..8d5b438 100644
--- a/fs/ramfs/file-nommu.c
+++ b/fs/ramfs/file-nommu.c
@@ -202,7 +202,7 @@
 					    unsigned long pgoff, unsigned long flags)
 {
 	unsigned long maxpages, lpages, nr, loop, ret;
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct page **pages = NULL, **ptr, *page;
 	loff_t isize;