[PATCH 0/8] nvme_fc: add dev_loss_tmo support

[James Smart]

On 5/13/2017 12:07 PM, James Smart wrote:
> FC, on the SCSI side, has long had a device loss timeout which governed
> how long it would hide connectivity loss to remote targets. The timeout
> value is maintained in the SCSI FC transport and admins are used to
> going there to maintain it.
>
> Eventually, the SCSI FC transport will be moved into something
> independent from and above SCSI so that SCSI and NVME protocols can
> be peers. That's fairly distant. In the meantime, to add the
> functionality now, and sync with the SCSI FC transport, the LLDD will
> be used as the conduit. The initial value for the timeout can be set
> by the LLDD when it creates the remoteport via
> nvme_fc_register_remoteport(). Later, if the value is updated via the
> SCSI transport, the LLDD can call a new nvme_fc routine to update
> the remoteport's dev_loss_tmo value, which can then be propagated to
> the controllers on the remoteport.
>
> As the fabrics implementation already has a similar behavior
> introduced on rdma, the ctrl_loss_tmo, which may be set on a
> controller basis (finer granularity than the FC port used for the
> connection), the nvme_fc transport will mediate and choose the lesser
> of the controllers value and the remoteports value.
>
> The patches were cut on nvme-4.12 after applying the patches in
> http://lists.infradead.org/pipermail/linux-nvme/2017-May/010156.html
> and
> http://lists.infradead.org/pipermail/linux-nvme/2017-May/010166.html
>
> James Smart (8):
>   nvme core: allow controller RESETTING to RECONNECTING transition
>   nvme_fc: change ctlr state assignments during reset/reconnect
>   nvme_fc: add a dev_loss_tmo field to the remoteport
>   nvme_fc: add dev_loss_tmo to controller
>   nvme_fc: check connectivity before initiating reconnects
>   nvme_fc: change failure code on remoteport connectivity loss
>   nvme_fc: move remote port get/put/free location
>   nvme_fc: add dev_loss_tmo timeout and remoteport resume support
>
>  drivers/nvme/host/core.c       |   1 +
>  drivers/nvme/host/fc.c         | 465 +++++++++++++++++++++++++++++++++++------
>  include/linux/nvme-fc-driver.h |  11 +-
>  3 files changed, 411 insertions(+), 66 deletions(-)
>


or comments on this series ?

-- james