set_host_byte(scmd, DID_OK);
ata_qc_for_each_raw(ap, qc, i) {
- if (qc->scsicmd != scmd)
- continue;
- if ((qc->flags & ATA_QCFLAG_ACTIVE) ||
- qc == qc->dev->link->deferred_qc)
+ if (qc->scsicmd == scmd &&
+ qc->flags & ATA_QCFLAG_ACTIVE)
break;
}
- if (i < ATA_MAX_QUEUE && qc == qc->dev->link->deferred_qc) {
- /*
- * This is a deferred command that timed out while
- * waiting for the command queue to drain. Since the qc
- * is not active yet (deferred_qc is still set, so the
- * deferred qc work has not issued the command yet),
- * simply signal the timeout by finishing the SCSI
- * command and clear the deferred qc to prevent the
- * deferred qc work from issuing this qc.
- */
- WARN_ON_ONCE(qc->flags & ATA_QCFLAG_ACTIVE);
- qc->dev->link->deferred_qc = NULL;
- cancel_work(&qc->dev->link->deferred_qc_work);
- set_host_byte(scmd, DID_TIME_OUT);
- scsi_eh_finish_cmd(scmd, &ap->eh_done_q);
- } else if (i < ATA_MAX_QUEUE) {
+ if (i < ATA_MAX_QUEUE) {
/* the scmd has an associated qc */
if (!(qc->flags & ATA_QCFLAG_EH)) {
/* which hasn't failed yet, timeout */
ap->pflags |= ATA_PFLAG_EH_PENDING;
/*
- * If we have a deferred qc, requeue it so that it is retried once EH
- * completes.
+ * If we have deferred QCs, requeue them so that the SCSI EH task can
+ * run.
*/
- ata_scsi_requeue_deferred_qc(ap);
+ ata_scsi_requeue_deferred_qc(ap, NULL);
if (!fastdrain)
return;
spin_unlock_irqrestore(ap->lock, flags);
}
-void ata_scsi_requeue_deferred_qc(struct ata_port *ap)
+enum scsi_timeout_action ata_scsi_requeue_deferred_qc(struct ata_port *ap,
+ struct scsi_cmnd *timedout_scmd)
{
+ enum scsi_timeout_action action = SCSI_EH_NOT_HANDLED;
+ struct ata_queued_cmd *qc;
struct ata_link *link;
+ u32 host_byte;
lockdep_assert_held(ap->lock);
/*
- * If we have a deferred qc when a reset occurs or NCQ commands fail,
- * do not try to be smart about what to do with this deferred command
- * and simply requeue it by completing it with DID_REQUEUE.
+ * If we have deferred QCs when a reset, a timeout or an NCQ command
+ * fails, do not try to be smart about what to do with the deferred
+ * commands and simply terminate them and let the SCSI layer decide
+ * what to do.
*/
ata_for_each_link(link, ap, PMP_FIRST) {
- struct ata_queued_cmd *qc = link->deferred_qc;
+ qc = link->deferred_qc;
+ if (!qc)
+ continue;
+
+ /*
+ * Clear the deferred QC so that the deferred work does not try
+ * to issue it.
+ */
+ link->deferred_qc = NULL;
+ cancel_work(&link->deferred_qc_work);
+
+ /*
+ * We are going to complete some scsi command, either with
+ * DID_TIME_OUT if the command timed out while waiting for being
+ * issued, or with DID_REQUEUE if another command timed out or
+ * we had a failed command. However, the block layer may re-issue
+ * these commands immediately, keeping the scsi host busy and
+ * thus preventing the SCSI EH task from running.
+ * So schedule EH on the port to prevent accepting new commands
+ * until everything is sorted out with the error or timeout that
+ * got us here in the first place. Note that we set EH pending
+ * on the port before calling ata_port_schedule_eh() so that we
+ * do not reenter this function from ata_eh_set_pending() with
+ * timedout_scmd being NULL and erroneously retry deferred QCs
+ * that have timed out on other links.
+ */
+ if (!ata_port_eh_scheduled(ap)) {
+ ap->pflags |= ATA_PFLAG_EH_PENDING;
+ ata_port_schedule_eh(ap);
+ }
- if (qc) {
- link->deferred_qc = NULL;
- cancel_work(&link->deferred_qc_work);
- ata_scsi_qc_done(qc, true, DID_REQUEUE << 16);
+ /*
+ * If we are being called from scsi_timeout(), then we have a
+ * non-NULL timedout_scmd. If the timed out command is for a
+ * deferred QC, terminate that deferred QC with DID_TIME_OUT and
+ * requeue all other deferred QCs. In this case we need to
+ * return SCSI_EH_DONE, because the timed out command was
+ * handled.
+ * If the timed out command is not for a deferred QC, we need to
+ * requeue all deferred QCs, and return SCSI_EH_NOT_HANDLED so
+ * that the timed out command gets added to the EH work queue
+ * with scsi_eh_scmd_add(), for later handling with libata EH
+ * ata_scsi_cmd_error_handler().
+ * If timedout_scmd is NULL, we simply need to requeue all
+ * deferred QCs and the return value does not matter as we were
+ * not called from scsi_timeout().
+ */
+ if (timedout_scmd && qc->scsicmd == timedout_scmd) {
+ host_byte = DID_TIME_OUT;
+ action = SCSI_EH_DONE;
+ } else {
+ host_byte = DID_REQUEUE;
}
+ ata_scsi_qc_done(qc, true, host_byte << 16);
}
+
+ return action;
}
static void ata_scsi_schedule_deferred_qc(struct ata_link *link)
return;
if (ata_port_eh_scheduled(ap)) {
- ata_scsi_requeue_deferred_qc(ap);
+ ata_scsi_requeue_deferred_qc(ap, NULL);
return;
}
if (!ap->ops->qc_defer(qc))
queue_work(system_highpri_wq, &link->deferred_qc_work);
}
+static enum scsi_timeout_action
+ata_scsi_retry_deferred_qc(struct ata_port *ap, struct scsi_cmnd *scmd)
+{
+ enum scsi_timeout_action action;
+ unsigned long flags;
+
+ spin_lock_irqsave(ap->lock, flags);
+ action = ata_scsi_requeue_deferred_qc(ap, scmd);
+ spin_unlock_irqrestore(ap->lock, flags);
+
+ return action;
+}
+
+enum scsi_timeout_action ata_scsi_eh_timed_out(struct scsi_cmnd *scmd)
+{
+ struct ata_port *ap = ata_shost_to_port(scmd->device->host);
+
+ /*
+ * ata_scsi_cmd_error_handler() takes care of commands that timed out
+ * while executing. However, if we have deferred QCs while a timeout
+ * triggers, we must requeue these commands for retry so that we do not
+ * unnecessarily delay starting the SCSI EH task until these deferred
+ * commands also time out.
+ */
+ return ata_scsi_retry_deferred_qc(ap, scmd);
+}
+EXPORT_SYMBOL_GPL(ata_scsi_eh_timed_out);
+
static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
{
struct ata_link *link = qc->dev->link;
if (qc->cdb[0] == ALLOW_MEDIUM_REMOVAL && qc->dev->sdev)
qc->dev->sdev->locked = 0;
- ata_scsi_qc_done(qc, true, SAM_STAT_CHECK_CONDITION);
+ if (cmd->result)
+ ata_scsi_qc_done(qc, false, 0);
+ else
+ ata_scsi_qc_done(qc, true, SAM_STAT_CHECK_CONDITION);
+ return;
+ }
+
+ if (cmd->result) {
+ ata_scsi_qc_done(qc, false, 0);
return;
}