Hi James & Co, Adding target-devel and Sebastian CC'
On Mon, 2017-02-27 at 15:28 -0800, James Smart wrote: > I'd like to announce the availability of the Broadcom (Emulex) FC Target > driver - efct. > This driver has been part of the Emulex OneCore Storage SDK tool kit for > Emulex > SLI-4 adapters. The SLI-4 adapters support 16Gb/s and higher adapters. > Although this > kit has supported FCoE in the past, it is currently limited to FC support. > > This driver provides the following: > - Target mode operation: > - Functional with LIO-based interfaces Glad to see the upstream push for this after all these years. :) > - Extensive use of hw offloads such as auto-xfer_rdy, auto-rsp, cmd > cpu spreading > - High login mode - thousands of logins > - T-10 DIF/PI support (inline and separate) > - NPIV support > - Concurrent Initiator support if needed > - Discovery engine has F_Port and fabric services emulation. > - Extended mgmt interfaces: > - firmware dump api, including dump to host memory for faster dumps > - Healthcheck operations and watchdogs > - Extended driver behaviors such as: > - polled mode operation > - multi-queue: cpu, roundrobin, or priority (but not tied to scsi-mq) > - long chained sgl's > - extensive internal logging and statistics > - Tuning parameters on modes and resource allocation to different > features > > Broadcom is looking to upstream this driver and would like review and > feedback. > The driver may be found at the following git repository: > g...@gitlab.com:jsmart/efct-Emulex_FC_Target.git > Can we get the patch series posted to linux-scsi and target-devel to start giving some initial feedback..? > > Some of the key questions we have are with lpfc : > 1) Coexistence vs integration > Currently, the efct driver maps to a different set of PCI ids than lpfc. > It's very clear there's an overlap with lpfc, both on SLI-4 hw as well > as initiator support. > Although target mode support can be simplistically added to lpfc, what > we've found is > that doing so means a lot of tradeoffs. Some of the target mode > features, when enabled, > impact the initiator support and how it would operate. > I don't really have much preference either way. > 2) SLI-3 support > lpfc provides SLI-3 support so that all FC adapters are supported, > including the older ones. > The form of the driver, based on its history, is SLI-3 with SLI-3 > adapted to SLI-4 at the point > it hits the hardware. efct does not support SLI-3. AFAIK I think Sebastian was using SLI-3, so he might have some comments here. Since he's been the main person using the original tcm_lpfc code from way back when, maybe it would be a good idea to send him a couple of SLI-4 HBAs to help with the upstreaming of efct..? > > 3) complexity of configuration knobs caused by the kitchen-sink of > features in lpfc ? > we are pushing the limit on needing per-instance attributes rather than > global module > parameters. This is exactly what /sys/kernel/config/target/efct/$WWPN/tpgt_1/attribute/ is intended for.
