ocfs2: allow for more than one data extent when creating xattr

Orabug: 18108070

ocfs2_xattr_extend_allocation() hits panic when creating xattr during
data extent alloc phase.  The problem occurs if due to local alloc
fragmentation, clusters are spread over multiple extents.  In this case
ocfs2_add_clusters_in_btree() finds no space to store more than one
extent record and therefore fails returning RESTART_META.  The situation
is anticipated for xattr update case but not xattr create case.  This
fix simply ports that code to create case.
Signed-off-by: NTariq Saeed <tariq.x.saeed@oracle.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/ocfs2/xattr.c

@@ -3200,8 +3200,15 @@ static int ocfs2_calc_xattr_set_need(struct inode *inode,
 			clusters_add += 1;
 		}
 	} else {
-		meta_add += 1;
 		credits += OCFS2_XATTR_BLOCK_CREATE_CREDITS;
+		if (xi->xi_value_len > OCFS2_XATTR_INLINE_SIZE) {
+			struct ocfs2_extent_list *el = &def_xv.xv.xr_list;
+			meta_add += ocfs2_extend_meta_needed(el);
+			credits += ocfs2_calc_extend_credits(inode->i_sb,
+							     el);
+		} else {
+			meta_add += 1;
+		}
 	}
 out:
 	if (clusters_need)