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

[Robert LeBlanc]

On Wed, Jun 7, 2017 at 12:30 PM, Robert LeBlanc <robert@xxxxxxxxxxxxx> wrote:
> On Wed, Jun 7, 2017 at 10:28 AM, Chris Leech <cleech@xxxxxxxxxx> wrote:
>> On Tue, Jun 06, 2017 at 12:07:10PM -0600, 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.
>>
>> Hi Robert,
>>
>> I don't think that passing the iface_rec structure directly from the
>> iscsid internals into a netlink message is a good way to go about this.
>> It's really big, there's an embedded list_head with user address
>> pointers that needs to be left out, and there are 32/64-bit layout
>> differences.
>>
>> Let me take a look at how you're proposing using this info for iSER, if
>> it makes sense I think we should come up with a better designed
>> structure for passing the information.
>>
>> Thanks,
>> Chris
>>
>
> Chris,
>
> Thank you for your feedback. I agree that the entire iface is probably
> overkill, it was more of a proof of concept. We are only using the
> ipaddress in the iface for iSER (in my patch), but I could see other
> drivers benefiting from some of the other data in the iface (mac,
> interface_name, vlan, etc) so I didn't want to be too restrictive so
> that it wouldn't have to be extended later. I've not worked on
> userspace/kernel interaction before so I need some guidance to make
> the transition between userspace and kernel versions smoother.
>
> This patchset works for what we need and it is very important for us
> (and I'm sure others once the feature is available) and I'm happy to
> put in the time to get it accepted upstream, I'm just new to kernel
> development and need some guidance.

Are there other comments/ideas/suggestions specifically from the
iSCSI/iSER guys? I'd like to keep this patch moving.

Thanks.

----------------
Robert LeBlanc
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