On Mon, 2017-06-12 at 17:23 -0700, Long Li wrote: > From: Long Li <[email protected]> > > FC disks are usually setup in a multipath system, and they don't want to > unconditionaly reset I/O on timeout. I/O timeout is detected by multipath > as a good time to failover and recover. > > Signed-off-by: Long Li <[email protected]> > --- > drivers/scsi/storvsc_drv.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c > index 8d955db..d60b5ea 100644 > --- a/drivers/scsi/storvsc_drv.c > +++ b/drivers/scsi/storvsc_drv.c > @@ -486,6 +486,7 @@ struct hv_host_device { > unsigned int port; > unsigned char path; > unsigned char target; > + bool is_fc; > }; > > struct storvsc_scan_work { > @@ -1495,6 +1496,11 @@ static int storvsc_host_reset_handler(struct scsi_cmnd > *scmnd) > */ > static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd) > { > + struct hv_host_device *host_dev = shost_priv(scmnd->device->host); > + > + if (host_dev->is_fc) > + return BLK_EH_NOT_HANDLED; > + > return BLK_EH_RESET_TIMER; > } > > @@ -1738,6 +1744,7 @@ static int storvsc_probe(struct hv_device *device, > > host_dev->port = host->host_no; > host_dev->dev = device; > + host_dev->is_fc = is_fc; > > > stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
Hello Long, As far as I know there is no other SCSI driver nor block driver in the Linux kernel tree that returns BLK_EH_RESET_TIMER unconditionally. Would a valid alternative fix be to remove storvsc_eh_timed_out() entirely? If not, what would break if that function would be removed entirely? Additionally, for FC, shouldn't that timeout handler handle the "port blocked" state? Shouldn't fc_eh_timed_out() be used for FC instead of just returning BLK_EH_NOT_HANDLED? Thanks, Bart.
