+ const enum fio_ddir ddir = acct_ddir(io_u);
+ unsigned long buflen = io_u->xfer_buflen;
+ int ret;
+
+ dprint_io_u(io_u, "queue");
+ fio_ro_check(td, io_u);
+
+ assert((io_u->flags & IO_U_F_FLIGHT) == 0);
+ io_u_set(td, io_u, IO_U_F_FLIGHT);
+
+ assert(fio_file_open(io_u->file));
+
+ /*
+ * If using a write iolog, store this entry.
+ */
+ log_io_u(td, io_u);
+
+ io_u->error = 0;
+ io_u->resid = 0;
+
+ if (td_ioengine_flagged(td, FIO_SYNCIO)) {
+ if (fio_fill_issue_time(td))
+ fio_gettime(&io_u->issue_time, NULL);
+
+ /*
+ * only used for iolog
+ */
+ if (td->o.read_iolog_file)
+ memcpy(&td->last_issue, &io_u->issue_time,
+ sizeof(io_u->issue_time));
+ }
+
+ if (ddir_rw(ddir)) {
+ td->io_issues[ddir]++;
+ td->io_issue_bytes[ddir] += buflen;
+ td->rate_io_issue_bytes[ddir] += buflen;
+ }
+
+ ret = td->io_ops->queue(td, io_u);
+
+ unlock_file(td, io_u->file);
+
+ if (ret == FIO_Q_BUSY && ddir_rw(ddir)) {
+ td->io_issues[ddir]--;
+ td->io_issue_bytes[ddir] -= buflen;
+ td->rate_io_issue_bytes[ddir] -= buflen;
+ io_u_clear(td, io_u, IO_U_F_FLIGHT);
+ }
+
+ /*
+ * If an error was seen and the io engine didn't propagate it
+ * back to 'td', do so.
+ */
+ if (io_u->error && !td->error)
+ td_verror(td, io_u->error, "td_io_queue");
+
+ /*
+ * Add warning for O_DIRECT so that users have an easier time
+ * spotting potentially bad alignment. If this triggers for the first
+ * IO, then it's likely an alignment problem or because the host fs
+ * does not support O_DIRECT
+ */
+ if (io_u->error == EINVAL && td->io_issues[io_u->ddir & 1] == 1 &&
+ td->o.odirect) {
+
+ log_info("fio: first direct IO errored. File system may not "
+ "support direct IO, or iomem_align= is bad. Try "
+ "setting direct=0.\n");
+ }
+
+ if (!td->io_ops->commit || io_u->ddir == DDIR_TRIM) {
+ io_u_mark_submit(td, 1);
+ io_u_mark_complete(td, 1);
+ }
+
+ if (ret == FIO_Q_COMPLETED) {
+ if (ddir_rw(io_u->ddir)) {
+ io_u_mark_depth(td, 1);
+ td->ts.total_io_u[io_u->ddir]++;
+ }
+ } else if (ret == FIO_Q_QUEUED) {
+ int r;
+
+ td->io_u_queued++;