From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bart Van Assche Subject: [PATCH 1/3] scsi_transport_srp: Block rport upon TL error even with fast_io_fail_tmo = off Date: Wed, 11 Dec 2013 17:05:22 +0100 Message-ID: <52A88D42.9060201@acm.org> References: <52A88CF9.206@acm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp03.stone-is.org ([87.238.162.66]:60798 "EHLO smtpgw.stone-is.be" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751474Ab3LKQF0 (ORCPT ); Wed, 11 Dec 2013 11:05:26 -0500 In-Reply-To: <52A88CF9.206@acm.org> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: David Dillow Cc: Vu Pham , Sebastian Riemer , James Bottomley , linux-rdma , linux-scsi The current behavior of the SRP transport layer when a transport layer error is encountered is to block SCSI command processing only if fast_io_fail_tmo != off. The current behavior of the FC transport layer when a transport layer error is encountered is to block SCSI command processing no matter which value fast_io_fail_tmo has been set to. Make the behavior of the SRP transport layer consistent with that of the FC transport layer to avoid confusion. Signed-off-by: Bart Van Assche Cc: David Dillow Cc: Vu Pham Cc: Sebastian Riemer Cc: James Bottomley --- drivers/scsi/scsi_transport_srp.c | 30 +++++++++++++++++------------- 1 file changed, 17 insertions(+), 13 deletions(-) diff --git a/drivers/scsi/scsi_transport_srp.c b/drivers/scsi/scsi_transport_srp.c index 2700a5a..8b9cb22 100644 --- a/drivers/scsi/scsi_transport_srp.c +++ b/drivers/scsi/scsi_transport_srp.c @@ -67,7 +67,8 @@ static inline struct Scsi_Host *rport_to_shost(struct srp_rport *r) * * 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 +80,9 @@ 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 && @@ -463,20 +467,20 @@ static void __srp_start_tl_fail_timers(struct srp_rport *rport) 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) { + 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); - queue_delayed_work(system_long_wq, - &rport->fast_io_fail_work, - 1UL * fast_io_fail_tmo * HZ); + 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); } - 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)); @@ -578,9 +582,9 @@ 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, -- 1.8.1.4