X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fscsi%2Fscsi_transport_srp.c;h=d47ffc8d3e431dc2524e30c378cd2fabb6406b74;hb=0c7f82189d2249153ee302fe4d02de15f165d220;hp=2700a5a09bd45a103b857b2f6a81da42834e4d28;hpb=62a3a12667ac551c0251d6437372c34a98dd991c;p=firefly-linux-kernel-4.4.55.git diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c index 2700a5a09bd4..d47ffc8d3e43 100644 --- a/drivers/scsi/scsi_transport_srp.c +++ b/drivers/scsi/scsi_transport_srp.c @@ -64,10 +64,14 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) /** * srp_tmo_valid() - check timeout combination validity + * @reconnect_delay: Reconnect delay in seconds. + * @fast_io_fail_tmo: Fast I/O fail timeout in seconds. + * @dev_loss_tmo: Device loss timeout in seconds. * * The combination of the timeout parameters must be such that SCSI commands * are finished in a reasonable time. Hence do not allow the fast I/O fail - * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT. Furthermore, these + * timeout to exceed SCSI_DEVICE_BLOCK_MAX_TIMEOUT nor allow dev_loss_tmo to + * exceed that limit if failing I/O fast has been disabled. Furthermore, these * parameters must be such that multipath can detect failed paths timely. * Hence do not allow all three parameters to be disabled simultaneously. */ @@ -79,6 +83,9 @@ int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, int dev_loss_tmo) return -EINVAL; if (fast_io_fail_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) return -EINVAL; + if (fast_io_fail_tmo < 0 && + dev_loss_tmo > SCSI_DEVICE_BLOCK_MAX_TIMEOUT) + return -EINVAL; if (dev_loss_tmo >= LONG_MAX / HZ) return -EINVAL; if (fast_io_fail_tmo >= 0 && dev_loss_tmo >= 0 && @@ -368,6 +375,7 @@ invalid: /** * srp_reconnect_work() - reconnect and schedule a new attempt if necessary + * @work: Work structure used for scheduling this operation. */ static void srp_reconnect_work(struct work_struct *work) { @@ -408,6 +416,7 @@ static void __rport_fail_io_fast(struct srp_rport *rport) /** * rport_fast_io_fail_timedout() - fast I/O failure timeout handler + * @work: Work structure used for scheduling this operation. */ static void rport_fast_io_fail_timedout(struct work_struct *work) { @@ -426,6 +435,7 @@ static void rport_fast_io_fail_timedout(struct work_struct *work) /** * 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) { @@ -452,42 +462,35 @@ static void __srp_start_tl_fail_timers(struct srp_rport *rport) lockdep_assert_held(&rport->mutex); - if (!rport->deleted) { - delay = rport->reconnect_delay; - fast_io_fail_tmo = rport->fast_io_fail_tmo; - dev_loss_tmo = rport->dev_loss_tmo; - pr_debug("%s current state: %d\n", - dev_name(&shost->shost_gendev), rport->state); + delay = rport->reconnect_delay; + fast_io_fail_tmo = rport->fast_io_fail_tmo; + dev_loss_tmo = rport->dev_loss_tmo; + pr_debug("%s current state: %d\n", dev_name(&shost->shost_gendev), + rport->state); - if (delay > 0) - queue_delayed_work(system_long_wq, - &rport->reconnect_work, - 1UL * delay * HZ); - if (fast_io_fail_tmo >= 0 && - srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { - pr_debug("%s new state: %d\n", - dev_name(&shost->shost_gendev), - rport->state); - scsi_target_block(&shost->shost_gendev); + if (rport->state == SRP_RPORT_LOST) + return; + if (delay > 0) + queue_delayed_work(system_long_wq, &rport->reconnect_work, + 1UL * delay * HZ); + if (srp_rport_set_state(rport, SRP_RPORT_BLOCKED) == 0) { + pr_debug("%s new state: %d\n", dev_name(&shost->shost_gendev), + rport->state); + scsi_target_block(&shost->shost_gendev); + if (fast_io_fail_tmo >= 0) queue_delayed_work(system_long_wq, &rport->fast_io_fail_work, 1UL * fast_io_fail_tmo * HZ); - } if (dev_loss_tmo >= 0) queue_delayed_work(system_long_wq, &rport->dev_loss_work, 1UL * dev_loss_tmo * HZ); - } else { - pr_debug("%s has already been deleted\n", - dev_name(&shost->shost_gendev)); - srp_rport_set_state(rport, SRP_RPORT_FAIL_FAST); - scsi_target_unblock(&shost->shost_gendev, - SDEV_TRANSPORT_OFFLINE); } } /** * srp_start_tl_fail_timers() - start the transport layer failure timers + * @rport: SRP target port. * * Start the transport layer fast I/O failure and device loss timers. Do not * modify a timer that was already started. @@ -502,6 +505,7 @@ EXPORT_SYMBOL(srp_start_tl_fail_timers); /** * scsi_request_fn_active() - number of kernel threads inside scsi_request_fn() + * @shost: SCSI host for which to count the number of scsi_request_fn() callers. */ static int scsi_request_fn_active(struct Scsi_Host *shost) { @@ -522,6 +526,7 @@ static int scsi_request_fn_active(struct Scsi_Host *shost) /** * 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 @@ -556,7 +561,7 @@ int srp_reconnect_rport(struct srp_rport *rport) scsi_target_block(&shost->shost_gendev); while (scsi_request_fn_active(shost)) msleep(20); - res = i->f->reconnect(rport); + 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) { @@ -578,9 +583,9 @@ int srp_reconnect_rport(struct srp_rport *rport) spin_unlock_irq(shost->host_lock); } else if (rport->state == SRP_RPORT_RUNNING) { /* - * srp_reconnect_rport() was invoked with fast_io_fail - * off. Mark the port as failed and start the TL failure - * timers if these had not yet been started. + * srp_reconnect_rport() has been invoked with fast_io_fail + * and dev_loss off. Mark the port as failed and start the TL + * failure timers if these had not yet been started. */ __rport_fail_io_fast(rport); scsi_target_unblock(&shost->shost_gendev, @@ -599,6 +604,7 @@ EXPORT_SYMBOL(srp_reconnect_rport); /** * srp_timed_out() - SRP transport intercept of the SCSI timeout EH + * @scmd: SCSI command. * * If a timeout occurs while an rport is in the blocked state, ask the SCSI * EH to continue waiting (BLK_EH_RESET_TIMER). Otherwise let the SCSI core @@ -622,10 +628,6 @@ static void srp_rport_release(struct device *dev) { struct srp_rport *rport = dev_to_rport(dev); - cancel_delayed_work_sync(&rport->reconnect_work); - cancel_delayed_work_sync(&rport->fast_io_fail_work); - cancel_delayed_work_sync(&rport->dev_loss_work); - put_device(dev->parent); kfree(rport); } @@ -674,6 +676,7 @@ static int srp_host_match(struct attribute_container *cont, struct device *dev) /** * srp_rport_get() - increment rport reference count + * @rport: SRP target port. */ void srp_rport_get(struct srp_rport *rport) { @@ -683,6 +686,7 @@ EXPORT_SYMBOL(srp_rport_get); /** * srp_rport_put() - decrement rport reference count + * @rport: SRP target port. */ void srp_rport_put(struct srp_rport *rport) { @@ -780,12 +784,6 @@ void srp_rport_del(struct srp_rport *rport) device_del(dev); transport_destroy_device(dev); - mutex_lock(&rport->mutex); - if (rport->state == SRP_RPORT_BLOCKED) - __rport_fail_io_fast(rport); - rport->deleted = true; - mutex_unlock(&rport->mutex); - put_device(dev); } EXPORT_SYMBOL_GPL(srp_rport_del); @@ -810,6 +808,27 @@ void srp_remove_host(struct Scsi_Host *shost) } EXPORT_SYMBOL_GPL(srp_remove_host); +/** + * srp_stop_rport_timers - stop the transport layer recovery timers + * + * Must be called after srp_remove_host() and scsi_remove_host(). The caller + * must hold a reference on the rport (rport->dev) and on the SCSI host + * (rport->dev.parent). + */ +void srp_stop_rport_timers(struct srp_rport *rport) +{ + mutex_lock(&rport->mutex); + if (rport->state == SRP_RPORT_BLOCKED) + __rport_fail_io_fast(rport); + srp_rport_set_state(rport, SRP_RPORT_LOST); + mutex_unlock(&rport->mutex); + + cancel_delayed_work_sync(&rport->reconnect_work); + cancel_delayed_work_sync(&rport->fast_io_fail_work); + cancel_delayed_work_sync(&rport->dev_loss_work); +} +EXPORT_SYMBOL_GPL(srp_stop_rport_timers); + static int srp_tsk_mgmt_response(struct Scsi_Host *shost, u64 nexus, u64 tm_id, int result) {