new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index a77c421..3799e8d 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -68,7 +68,7 @@
 static int sysv_readdir(struct file * filp, void * dirent, filldir_t filldir)
 {
 	unsigned long pos = filp->f_pos;
-	struct inode *inode = filp->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(filp);
 	struct super_block *sb = inode->i_sb;
 	unsigned offset = pos & ~PAGE_CACHE_MASK;
 	unsigned long n = pos >> PAGE_CACHE_SHIFT;