----- Original Message ----- >> We will need James to chime in why your patch did not go in. My >> assumption is the lack of response to his question left it in limbo. > > That's a good assumption. A maintainers list folder is usually sorted > by thread and by activity. I mark patches for inclusion, but if a > thread is expecting a reply I don't do anything since it comes back to > the top again once there's activity on it. This kernel business shouldn't be about you. It should be about making the kernel better today than it is tomorrow, so that people can use it and can use it with more devices, without bugs. >> The likely modification to your patch would be to remove all the >> unused added flags rather than staking out the territory. > > Well, yes, but the question is broader than that. In theory we can't > support SAS2.0 expanders until we support all of their features. That's strictly _your_ theory and what it does, it excludes functionality from the kernel instead of enabling it. When two vendors send you a patch that enables the same functionality and ask for it to be included into the kernel, because people are using this functionality, you should listen and include it. > Table > to Table routing is one, but self configuration is another. That's a very uninformed statement. It shows your utter lack of familiarity of the SAS protocol. > If there > are no current self configuring expanders, I'm OK with just doing table > to table ... but the extra bits made me wonder. Yes, you should simply include the patch. > > James > > >> What kind of testing was involved in your patch? I have not merged >> yours in here to try it out on our enclosures. Either way, I want to >> see some movement; James any directions? >> >> Sincerely -- Mark Salyzyn >> >> -----Original Message----- >> From: Luben Tuikov [mailto:ltuikov@xxxxxxxxx] >> Sent: Wednesday, August 31, 2011 1:43 PM >> To: Mark Salyzyn; linux-scsi@xxxxxxxxxxxxxxx >> Cc: Darrick J Wong; James Bottomley >> Subject: Re: [PATCH] [SCSI]: Allow expander T-T attachments >> >> ----- Original Message ----- >> >> > From: Mark Salyzyn <mark_salyzyn@xxxxxxxxxxxxxx> >> > To: linux-scsi@xxxxxxxxxxxxxxx >> > Cc: Luben Tuikov <ltuikov@xxxxxxxxx>; Darrick J Wong > <djwong@xxxxxxxxxx>; James Bottomley <jbottomley@xxxxxxxxxxxxx> >> > Sent: Wednesday, August 31, 2011 6:44 AM >> > Subject: Re: [PATCH] [SCSI]: Allow expander T-T attachments >> > >> > Since Luben's patch on July 28th 2011 went nowhere, as there was > an >> > unanswered question regarding the future-proofing that Luben added in. >> >> Are you saying that the patch I posted, >> http://marc.info/?t=131182720200001&r=1&w=2, didn't go in >> because I didn't entertain Bottomley's unrelated question therein? >> Or are you saying that it did go in based on TECHNICAL CONTENT? I.e. it >> was buggy, or wrong, etc? >> >> > I decided to submit a simplified focussed patch we have been using for > the >> >> By "simplified, focused" you mean one which doesn't define 2 > out of 3 flags of >> REPORT GENERAL SMP response? >> >> > past year testing with the Xyratex enclosures (5U84, 2U24, chained > with >> > *many* peered expanders with Table to Table routing) that should >> > hopefully expedite things and will be on hot standby to refactor as >> > requested (including tossing this baby and refactoring Luben's > patch >> > should he be too busy, no hair off my back) >> >> Now onto technical matter: >> 1) I'd call the flag "t2t_supp" to a) fit in with the rest of > the spirit of the >> code as other fields are also called "_supp", and to b) actually > convey >> the meaning of "table-to-table supported. Your naming of this flag >> "table_to_table" implicitly means "table to table > supported". >> 2) Please also add the debug output as my patch did. People will >> be wondering what went wrong if their domain didn't work, and the >> debug print in my original patch would tell them that. >> 3) You don't check that the parent also supports T2T. That's a bug. >> 4) Your patch logically does this: P=T && C!=S && (C is T2T > || C!=T), >> which after expansion is equivalent to: >> (P==T) && ((C!=S && C!=T2T) || C==D) ==> fail >> where the outmost parens are an if (). Albeit from not being entirely > correct, >> it also obfuscates what is being sought after. I chose to use the negation > for >> successful check to make it more clear: >> (P==T) && (C==S || (C==T && P==T2T && C==T2T)) > ==> success, >> Translates to >> "If parent phy is T, and If child phy is S OR (child is T and child > and parent >> both support table to table) then we're okay, else report an > error." >> Which is: T<-S is okay, and T<-T is okay if both parent and child > support it. >> >> Alternatively, Bottomley could just add my patch upstream. >> >> > Please note, as I am *stuck* on Outlook as per company policy, the >> > following inline content will likely not patch clean even emailed as >> > 'Plain Text', the enclosed attached file should do the job. I > have >> > Cc'd >> > all the folks that originated the files in libsas, as there was no >> > listed MAINTAINERs. >> > >> > NB: this patch (and Luben's independent patch) results in an ABI > break >> > as the structures change 'shape' and thus result in a > different set of >> > libsas export signatures. I have an internal patch I use that > preserves >> > the structure shapes and thus the ABI; but would be considered >> > inappropriate for the pristine trees. Said alternate patch would work >> > fine for a Distribution tree where ABI concerns are an issue. >> > >> > Checkpatch.pl reports clean. >> > >> > Sincerely -- Mark Salyzyn >> > >> > Cc: Luben Tuikov <tuikov@xxxxxxxxx> >> > Cc: Darrick J Wong <djwong@xxxxxxxxxx> >> > Cc: James Bottomley <jbottomley@xxxxxxxxxxxxx> >> > >> > Signed-off-by: Mark Salyzyn <msalyzyn@xxxxxxxxxxxxxx> >> > >> > drivers/scsi/libsas/sas_expander.c | 6 +++++- >> > include/scsi/libsas.h | 1 + >> > include/scsi/sas.h | 6 ++++-- >> > 3 files changed, 10 insertions(+), 3 deletions(-) >> > >> > diff -ru scsi-misc-2.6/drivers/scsi/libsas/sas_expander.c >> > scsi-misc-2.6.new/drivers/scsi/libsas/sas_expander.c >> > --- scsi-misc-2.6/drivers/scsi/libsas/sas_expander.c 2011-08-31 >> > 08:32:21.000000000 -0400 >> > +++ scsi-misc-2.6.new/drivers/scsi/libsas/sas_expander.c >> > 2011-08-31 09:07:31.000000000 -0400 >> > @@ -331,6 +331,7 @@ >> > dev->ex_dev.num_phys = min(rg->num_phys, > (u8)MAX_EXPANDER_PHYS); >> > dev->ex_dev.conf_route_table = rg->conf_route_table; >> > dev->ex_dev.configuring = rg->configuring; >> > + dev->ex_dev.table_to_table = rg->table_to_table; >> > memcpy(dev->ex_dev.enclosure_logical_id, >> > rg->enclosure_logical_id, 8); >> > } >> > >> > @@ -1239,7 +1240,10 @@ >> > res = -ENODEV; >> > } >> > } else if (parent_phy->routing_attr == >> > TABLE_ROUTING && >> > - child_phy->routing_attr != >> > SUBTRACTIVE_ROUTING) { >> > + child_phy->routing_attr != >> > + SUBTRACTIVE_ROUTING && >> > + (child_ex->table_to_table == 0 || >> > + child_phy->routing_attr != >> > TABLE_ROUTING)) { >> > sas_print_parent_topology_bug(child, >> > parent_phy, child_phy); >> > res = -ENODEV; >> > } >> > diff -ru scsi-misc-2.6/include/scsi/libsas.h >> > scsi-misc-2.6.new/include/scsi/libsas.h >> > --- scsi-misc-2.6/include/scsi/libsas.h 2011-08-31 > 08:32:22.000000000 >> > -0400 >> > +++ scsi-misc-2.6.new/include/scsi/libsas.h 2011-08-31 >> > 09:07:31.000000000 -0400 >> > @@ -144,6 +144,7 @@ >> > u8 num_phys; >> > u8 configuring:1; >> > u8 conf_route_table:1; >> > + u8 table_to_table:1; >> > u8 enclosure_logical_id[8]; >> > >> > struct ex_phy *ex_phy; >> > diff -ru scsi-misc-2.6/include/scsi/sas.h >> > scsi-misc-2.6.new/include/scsi/sas.h >> > --- scsi-misc-2.6/include/scsi/sas.h 2011-08-31 08:32:22.000000000 >> > -0400 >> > +++ scsi-misc-2.6.new/include/scsi/sas.h 2011-08-31 >> > 09:07:31.000000000 -0400 >> > @@ -341,7 +341,8 @@ >> > >> > u8 conf_route_table:1; >> > u8 configuring:1; >> > - u8 _r_b:6; >> > + u8 _r_b:5; >> > + u8 table_to_table:1; >> > >> > u8 _r_c; >> > >> > @@ -528,7 +529,8 @@ >> > u8 _r_a; >> > u8 num_phys; >> > >> > - u8 _r_b:6; >> > + u8 table_to_table:1; >> > + u8 _r_b:5; >> > u8 configuring:1; >> > u8 conf_route_table:1; >> > >> ______________________________________________________________________ >> This email may contain privileged or confidential information, which should > only be used for the purpose for which it was sent by Xyratex. No further rights > or licenses are granted to use such information. If you are not the intended > recipient of this message, please notify the sender by return and delete it. You > may not use, copy, disclose or rely on the information contained in it. >> >> Internet email is susceptible to data corruption, interception and > unauthorised amendment for which Xyratex does not accept liability. While we > have taken reasonable precautions to ensure that this email is free of viruses, > Xyratex does not accept liability for the presence of any computer viruses in > this email, nor for any losses caused as a result of viruses. >> >> Xyratex Technology Limited (03134912), Registered in England & Wales, > Registered Office, Langstone Road, Havant, Hampshire, PO9 1SA. >> >> The Xyratex group of companies also includes, Xyratex Ltd, registered in > Bermuda, Xyratex International Inc, registered in California, Xyratex (Malaysia) > Sdn Bhd registered in Malaysia, Xyratex Technology (Wuxi) Co Ltd registered in > The People's Republic of China and Xyratex Japan Limited registered in > Japan. >> ______________________________________________________________________ >> >> >> -- >> To unsubscribe from this list: 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 > -- To unsubscribe from this list: 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
