new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c
index 7493428..2db7021 100644
--- a/fs/nfsd/nfsctl.c
+++ b/fs/nfsd/nfsctl.c
@@ -85,7 +85,7 @@
 
 static ssize_t nfsctl_transaction_write(struct file *file, const char __user *buf, size_t size, loff_t *pos)
 {
-	ino_t ino =  file->f_path.dentry->d_inode->i_ino;
+	ino_t ino =  file_inode(file)->i_ino;
 	char *data;
 	ssize_t rv;