fs: ceph: new helper: file_inode(file)

Signed-off-by: Libo Chen <clbchenlibo.chen@huawei.com>
Signed-off-by: Sage Weil <sage@inktank.com>

fs/ceph/file.c

@@ -1201,7 +1201,7 @@ static long ceph_fallocate(struct file *file, int mode,
 				loff_t offset, loff_t length)
 {
 	struct ceph_file_info *fi = file->private_data;
-	struct inode *inode = file->f_dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct ceph_inode_info *ci = ceph_inode(inode);
 	struct ceph_osd_client *osdc =
 		&ceph_inode_to_client(inode)->client->osdc;