+
+ /*
+ * We get PR data locks even for O_DIRECT. This allows
+ * concurrent O_DIRECT I/O but doesn't let O_DIRECT with
+ * extending and buffered zeroing writes race. If they did
+ * race then the buffered zeroing could be written back after
+ * the O_DIRECT I/O. It's one thing to tell people not to mix
+ * buffered and O_DIRECT writes, but expecting them to
+ * understand that file extension is also an implicit buffered
+ * write is too much. By getting the PR we force writeback of
+ * the buffered zeroing before proceeding.
+ */
+ ret = ocfs2_data_lock(inode, 0);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ ocfs2_data_unlock(inode, 0);
+