diff options
| -rw-r--r-- | drivers/ata/libata-core.c | 5 | ||||
| -rw-r--r-- | drivers/ata/libata-eh.c | 6 | ||||
| -rw-r--r-- | drivers/ata/libata-scsi.c | 93 | ||||
| -rw-r--r-- | drivers/ata/libata.h | 2 | ||||
| -rw-r--r-- | include/linux/libata.h | 3 |
5 files changed, 109 insertions, 0 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index b96105481784..e888f2445692 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -5644,6 +5644,7 @@ struct ata_port *ata_port_alloc(struct ata_host *host) mutex_init(&ap->scsi_scan_mutex); INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug); INIT_DELAYED_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan); + INIT_WORK(&ap->deferred_qc_work, ata_scsi_deferred_qc_work); INIT_LIST_HEAD(&ap->eh_done_q); init_waitqueue_head(&ap->eh_wait_q); init_completion(&ap->park_req_pending); @@ -6256,6 +6257,10 @@ static void ata_port_detach(struct ata_port *ap) } } + /* Make sure the deferred qc work finished. */ + cancel_work_sync(&ap->deferred_qc_work); + WARN_ON(ap->deferred_qc); + /* Tell EH to disable all devices */ ap->pflags |= ATA_PFLAG_UNLOADING; ata_port_schedule_eh(ap); diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index f4c9541d1910..72a22b6c9682 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -918,6 +918,12 @@ static void ata_eh_set_pending(struct ata_port *ap, bool fastdrain) ap->pflags |= ATA_PFLAG_EH_PENDING; + /* + * If we have a deferred qc, requeue it so that it is retried once EH + * completes. + */ + ata_scsi_requeue_deferred_qc(ap); + if (!fastdrain) return; diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index be620bc04584..e7898bf56308 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1658,8 +1658,77 @@ static void ata_qc_done(struct ata_queued_cmd *qc) done(cmd); } +void ata_scsi_deferred_qc_work(struct work_struct *work) +{ + struct ata_port *ap = + container_of(work, struct ata_port, deferred_qc_work); + struct ata_queued_cmd *qc; + unsigned long flags; + + spin_lock_irqsave(ap->lock, flags); + + /* + * If we still have a deferred qc and we are not in EH, issue it. In + * such case, we should not need any more deferring the qc, so warn if + * qc_defer() says otherwise. + */ + qc = ap->deferred_qc; + if (qc && !ata_port_eh_scheduled(ap)) { + WARN_ON_ONCE(ap->ops->qc_defer(qc)); + ap->deferred_qc = NULL; + ata_qc_issue(qc); + } + + spin_unlock_irqrestore(ap->lock, flags); +} + +void ata_scsi_requeue_deferred_qc(struct ata_port *ap) +{ + struct ata_queued_cmd *qc = ap->deferred_qc; + struct scsi_cmnd *scmd; + + 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 retry it by completing it with DID_SOFT_ERROR. + */ + if (!qc) + return; + + scmd = qc->scsicmd; + ap->deferred_qc = NULL; + ata_qc_free(qc); + scmd->result = (DID_SOFT_ERROR << 16); + scsi_done(scmd); +} + +static void ata_scsi_schedule_deferred_qc(struct ata_port *ap) +{ + struct ata_queued_cmd *qc = ap->deferred_qc; + + lockdep_assert_held(ap->lock); + + /* + * If we have a deferred qc, then qc_defer() is defined and we can use + * this callback to determine if this qc is good to go, unless EH has + * been scheduled. + */ + if (!qc) + return; + + if (ata_port_eh_scheduled(ap)) { + ata_scsi_requeue_deferred_qc(ap); + return; + } + if (!ap->ops->qc_defer(qc)) + queue_work(system_highpri_wq, &ap->deferred_qc_work); +} + static void ata_scsi_qc_complete(struct ata_queued_cmd *qc) { + struct ata_port *ap = qc->ap; struct scsi_cmnd *cmd = qc->scsicmd; u8 *cdb = cmd->cmnd; bool have_sense = qc->flags & ATA_QCFLAG_SENSE_VALID; @@ -1689,6 +1758,8 @@ static void ata_scsi_qc_complete(struct ata_queued_cmd *qc) } ata_qc_done(qc); + + ata_scsi_schedule_deferred_qc(ap); } static int ata_scsi_qc_issue(struct ata_port *ap, struct ata_queued_cmd *qc) @@ -1698,6 +1769,16 @@ static int ata_scsi_qc_issue(struct ata_port *ap, struct ata_queued_cmd *qc) if (!ap->ops->qc_defer) goto issue; + /* + * If we already have a deferred qc, then rely on the SCSI layer to + * requeue and defer all incoming commands until the deferred qc is + * processed, once all on-going commands complete. + */ + if (ap->deferred_qc) { + ata_qc_free(qc); + return SCSI_MLQUEUE_DEVICE_BUSY; + } + /* Check if the command needs to be deferred. */ ret = ap->ops->qc_defer(qc); switch (ret) { @@ -1716,6 +1797,18 @@ static int ata_scsi_qc_issue(struct ata_port *ap, struct ata_queued_cmd *qc) } if (ret) { + /* + * We must defer this qc: if this is not an NCQ command, keep + * this qc as a deferred one and report to the SCSI layer that + * we issued it so that it is not requeued. The deferred qc will + * be issued with the port deferred_qc_work once all on-going + * commands complete. + */ + if (!ata_is_ncq(qc->tf.protocol)) { + ap->deferred_qc = qc; + return 0; + } + /* Force a requeue of the command to defer its execution. */ ata_qc_free(qc); return ret; diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h index 89dd0ae2b991..9b4e578ad07e 100644 --- a/drivers/ata/libata.h +++ b/drivers/ata/libata.h @@ -166,6 +166,8 @@ void ata_scsi_sdev_config(struct scsi_device *sdev); int ata_scsi_dev_config(struct scsi_device *sdev, struct queue_limits *lim, struct ata_device *dev); int __ata_scsi_queuecmd(struct scsi_cmnd *scmd, struct ata_device *dev); +void ata_scsi_deferred_qc_work(struct work_struct *work); +void ata_scsi_requeue_deferred_qc(struct ata_port *ap); /* libata-eh.c */ extern unsigned int ata_internal_cmd_timeout(struct ata_device *dev, u8 cmd); diff --git a/include/linux/libata.h b/include/linux/libata.h index aa88244f3d83..d612d4c1660a 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -899,6 +899,9 @@ struct ata_port { u64 qc_active; int nr_active_links; /* #links with active qcs */ + struct work_struct deferred_qc_work; + struct ata_queued_cmd *deferred_qc; + struct ata_link link; /* host default link */ struct ata_link *slave_link; /* see ata_slave_link_init() */ |