>On Mon, 12 Jun 2006, Mike Christie wrote: > Date: Mon, 12 Jun 2006 16:35:45 -0500 > From: Mike Christie <michaelc@xxxxxxxxxxx> > To: Ravi Anand <ravi.anand@xxxxxxxxxx> > CC: Doug Maxey <dwm@xxxxxxxxxxxxxxxx>, > David Somayajulu <davidcs2005@xxxxxxxxx>, > Duane Grigsby <duane.grigsby@xxxxxxxxxx>, > linux-scsi@xxxxxxxxxxxxxxx, dwm@xxxxxxxxxxxxxx > Subject: Re: [RFC] qla4xxx: TODO for re-submission > User-Agent: Thunderbird 1.5 (X11/20060313) > > Ravi Anand wrote: > >> On Mon, 12 Jun 2006, Mike Christie wrote: > >> Doug Maxey wrote: > >>> 5) add the block layer code. > >> Some related issues that we have discussed offlist about this and should > >> probably be discussed here are: > >> > >> - Are we supposed to follow FC's lead and remove the devices (rport, > >> session, target, scsi_device, etc) if the dev_loss_tmo fires. Currently > >> for software iscsi, we leave the devices/session. This was to reduce > >> memory allocations and because software iscsi has to basically poll the > >> connection during connect as part of the relogin process. So unlike FC > >> or hw iscsi, if we remove the devices/structs we have to end up > >> rebuilding some of them right away anyways. > >> > >> Removing the devices has the benefit of simplifying the scsi/iscsi code. > >> > >> - Scanning. We currently do scanning for open-iscsi in userspace. For > >> iscsi root this requires distro support. SUSE has it. Fedora is working > >> on it. There is also Debian and Gentoo users or maintainers posting > >> about working on it. For qla4xxx, we could stick the scanning in the > >> kernel like FC and distros would not have to worry about it, but since > >> they have to get this working for software iscsi do we just keep the > >> scanning in userspace? > > > > Our preference is also to have the scanning for all the HBA's which > > does the discovery of the tgt's in the kernel space. This way we are > > consistent with all the HBA's which does the port discovery like > > the FC HBA's. Our iSCSI HBA's is similar in that regard. > > Yeah, but your HBA can also function in connection mode and just use > open-iscsi's login code too. I am not saying that is that way to go. I > am just saying that there are alternatives. Agreed. But it was added later on. So the driver always used the session mode. > > > > > As you have already stated, it simplies support from distro perspective > > as well. > > > > It does for qla4xxx, but I think you then have to go and fix it so > iscsi_tcp and iscsi_iser sync up with userspace correctly if you convert > them. Either that or we maintain two ways of scanning for iscsi drivers. I like the later part. Keeping it seperate. Ravi - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
