Re: [PATCH 0/7] Enable iSCSI offload drivers to use information from iface.

[Hannes Reinecke <hare@suse.de>]

On 06/06/2017 08:07 PM, Robert LeBlanc wrote:
> This patchset enables iSCSI offload drivers to have access to the iface
> information provided by iscsid. This allows users to have more control
> of how the driver connects to the iSCSI target. iSER is updated to use
> iface.ipaddress to set the source IP address if configured. This allows
> iSER to use multiple ports on the same network or in more complicated
> routed configurations.
> 
> Since there is already a change to the function parameters, dst_addr
> is upgraded to sockaddr_storage so that it is more future proof and makes
> the size of the struct static and not dependent on checking the SA_FAMILY.
> 
> This is dependent on updates to Open-iSCSI.
> 
> Robert LeBlanc (7):
>   scsi/scsi_transport_iscsi: Add iface struct to kernel.
>   scsi/scsi_transport_iscsi: Update ep_connect to include iface.
>   ib/iSER: Add binding to source IP address.
>   scsi/be2iscsi: Update beiscsi_ep_connect to accept iface and
>     sockaddr_storage.
>   scsi/bnx2i: Update bnx2i_ep_connect to accept iface and
>     sockaddr_storage.
>   scsi/cxgbi: Update cxgbi_ep_connect to accept iface and
>     sockaddr_storage.
>   scsi/qla4xxx: Update qla4xxx_ep_connect to accept iface and
>     sockaddr_storage.
> 
>  drivers/infiniband/ulp/iser/iscsi_iser.c     |  33 +++++++--
>  drivers/infiniband/ulp/iser/iscsi_iser.h     |   4 +-
>  drivers/infiniband/ulp/iser/iser_initiator.c |   1 +
>  drivers/infiniband/ulp/iser/iser_memory.c    |   1 +
>  drivers/infiniband/ulp/iser/iser_verbs.c     |   8 ++-
>  drivers/scsi/be2iscsi/be_cmds.c              |   1 +
>  drivers/scsi/be2iscsi/be_iscsi.c             |   8 ++-
>  drivers/scsi/be2iscsi/be_iscsi.h             |   5 +-
>  drivers/scsi/be2iscsi/be_main.c              |   1 +
>  drivers/scsi/be2iscsi/be_mgmt.c              |   1 +
>  drivers/scsi/bnx2i/bnx2i_hwi.c               |   1 +
>  drivers/scsi/bnx2i/bnx2i_iscsi.c             |  13 ++--
>  drivers/scsi/cxgbi/libcxgbi.c                |  15 ++--
>  drivers/scsi/cxgbi/libcxgbi.h                |   2 +-
>  drivers/scsi/qla4xxx/ql4_os.c                |  15 ++--
>  drivers/scsi/scsi_transport_iscsi.c          |   9 ++-
>  include/scsi/scsi_transport_iscsi.h          | 100 ++++++++++++++++++++++++++-
>  17 files changed, 179 insertions(+), 39 deletions(-)
> 
Hmm.

That it rather large, just for passing information from userspace into
the kernel.
What is the actual benefit here?

Personally, I would rather see iscsid creating tap interfaces associated
with each iSCSI offload interface, and having the kernel accessing the
information from _that_.
Then each connection would have a network interface attached to it, and
could retrieve the information from there.
Plus we could use 'normal' userspace tools like 'ip' to configure the
iSCSI offload network.

Cheers,

Hannes
-- 
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare@suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg
GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG Nürnberg)