Ejemplo n.º 1
0
/**
 * srp_reconnect_rport() - reconnect to an SRP target port
 * @rport: SRP target port.
 *
 * Blocks SCSI command queueing before invoking reconnect() such that
 * queuecommand() won't be invoked concurrently with reconnect() from outside
 * the SCSI EH. This is important since a reconnect() implementation may
 * reallocate resources needed by queuecommand().
 *
 * Notes:
 * - This function neither waits until outstanding requests have finished nor
 *   tries to abort these. It is the responsibility of the reconnect()
 *   function to finish outstanding commands before reconnecting to the target
 *   port.
 * - It is the responsibility of the caller to ensure that the resources
 *   reallocated by the reconnect() function won't be used while this function
 *   is in progress. One possible strategy is to invoke this function from
 *   the context of the SCSI EH thread only. Another possible strategy is to
 *   lock the rport mutex inside each SCSI LLD callback that can be invoked by
 *   the SCSI EH (the scsi_host_template.eh_*() functions and also the
 *   scsi_host_template.queuecommand() function).
 */
int srp_reconnect_rport(struct srp_rport *rport)
{
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct srp_internal *i = to_srp_internal(shost->transportt);
	struct scsi_device *sdev;
	int res;

	pr_debug("SCSI host %s\n", dev_name(&shost->shost_gendev));

	res = mutex_lock_interruptible(&rport->mutex);
	if (res)
		goto out;
	scsi_target_block(&shost->shost_gendev);
	res = rport->state != SRP_RPORT_LOST ? i->f->reconnect(rport) : -ENODEV;
	pr_debug("%s (state %d): transport.reconnect() returned %d\n",
		 dev_name(&shost->shost_gendev), rport->state, res);
	if (res == 0) {
		cancel_delayed_work(&rport->fast_io_fail_work);
		cancel_delayed_work(&rport->dev_loss_work);

		rport->failed_reconnects = 0;
		srp_rport_set_state(rport, SRP_RPORT_RUNNING);
		scsi_target_unblock(&shost->shost_gendev, SDEV_RUNNING);
		/*
		 * If the SCSI error handler has offlined one or more devices,
		 * invoking scsi_target_unblock() won't change the state of
		 * these devices into running so do that explicitly.
		 */
		spin_lock_irq(shost->host_lock);
		__shost_for_each_device(sdev, shost)
			if (sdev->sdev_state == SDEV_OFFLINE)
				sdev->sdev_state = SDEV_RUNNING;
		spin_unlock_irq(shost->host_lock);
	} else if (rport->state == SRP_RPORT_RUNNING) {
Ejemplo n.º 2
0
static void __rport_fail_io_fast(struct srp_rport *rport)
{
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct srp_internal *i;

	lockdep_assert_held(&rport->mutex);

	if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST))
		return;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 6, 0) || defined(CONFIG_COMPAT_SCSI_TARGET_UNBLOCK)
	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);
#else
	scsi_target_unblock(rport->dev.parent);
#endif

	/* Involve the LLD if possible to terminate all I/O on the rport. */
	i = to_srp_internal(shost->transportt);
	if (i->f->terminate_rport_io)
		i->f->terminate_rport_io(rport);
}
Ejemplo n.º 3
0
/**
 * rport_dev_loss_timedout() - device loss timeout handler
 * @work: Work structure used for scheduling this operation.
 */
static void rport_dev_loss_timedout(struct work_struct *work)
{
	struct srp_rport *rport = container_of(to_delayed_work(work),
					struct srp_rport, dev_loss_work);
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct srp_internal *i = to_srp_internal(shost->transportt);

	pr_info("dev_loss_tmo expired for SRP %s / %s.\n",
		dev_name(&rport->dev), dev_name(&shost->shost_gendev));

	mutex_lock(&rport->mutex);
	WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(3, 6, 0) || defined(CONFIG_COMPAT_SCSI_TARGET_UNBLOCK)
	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);
#else
	scsi_target_unblock(rport->dev.parent);
#endif
	mutex_unlock(&rport->mutex);

	i->f->rport_delete(rport);
}
Ejemplo n.º 4
0
static void __rport_fail_io_fast(struct srp_rport *rport)
{
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct srp_internal *i;

	lockdep_assert_held(&rport->mutex);

	if (srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST))
		return;
	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);

	/* Involve the LLD if possible to terminate all I/O on the rport. */
	i = to_srp_internal(shost->transportt);
	if (i->f->terminate_rport_io)
		i->f->terminate_rport_io(rport);
}
Ejemplo n.º 5
0
/**
 * rport_dev_loss_timedout() - device loss timeout handler
 * @work: Work structure used for scheduling this operation.
 */
static void rport_dev_loss_timedout(struct work_struct *work)
{
	struct srp_rport *rport = container_of(to_delayed_work(work),
					struct srp_rport, dev_loss_work);
	struct Scsi_Host *shost = rport_to_shost(rport);
	struct srp_internal *i = to_srp_internal(shost->transportt);

	pr_info("dev_loss_tmo expired for SRP %s / %s.\n",
		dev_name(&rport->dev), dev_name(&shost->shost_gendev));

	mutex_lock(&rport->mutex);
	WARN_ON(srp_rport_set_state(rport, SRP_RPORT_LOST) != 0);
	scsi_target_unblock(rport->dev.parent, SDEV_TRANSPORT_OFFLINE);
	mutex_unlock(&rport->mutex);

	i->f->rport_delete(rport);
}