scsi: lpfc: Restore clearing of NLP_UNREG_INP in ndlp->nlp_flag

Commit 32566a6 ("scsi: lpfc: Remove NLP_RELEASE_RPI flag from nodelist
structure") introduced a regression with SLI-3 adapters (e.g. LPe12000 8Gb)
where a Link Down / Link Up such as caused by disabling an host FC switch
port would result in the devices remaining in the transport-offline state
and multipath reporting them as failed.  This problem was not seen with
newer SLI-4 adapters.

The problem was caused by portions of the patch which removed the functions
__lpfc_sli_rpi_release() and lpfc_sli_rpi_release() and all their callers.
This was presumably because with the removal of the NLP_RELEASE_RPI flag
there was no need to free the rpi.

However, __lpfc_sli_rpi_release() and lpfc_sli_rpi_release() which calls it
reset the NLP_UNREG_INP flag. And, lpfc_sli_def_mbox_cmpl() has a path
where __lpfc_sli_rpi_release() was called in a particular case where
NLP_UNREG_INP was not otherwise cleared because of other conditions.

Restoring the else clause of this conditional and simply clearing the
NLP_UNREG_INP flag appears to resolve the problem with SLI-3 adapters.  It
should be noted that the code path in question is not specific to SLI-3,
but there are other SLI-4 code paths which may have masked the issue.

Fixes: 32566a6 ("scsi: lpfc: Remove NLP_RELEASE_RPI flag from nodelist structure")
Cc: [email protected]
Tested-by: Marco Patalano <[email protected]>
Signed-off-by: Ewan D. Milne <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Justin Tee <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

Author: Ewan D. Milne

drivers/scsi/lpfc/lpfc_sli.c

@@ -2921,6 +2921,8 @@ lpfc_sli_def_mbox_cmpl(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmb)
 				clear_bit(NLP_UNREG_INP, &ndlp->nlp_flag);
 				ndlp->nlp_defer_did = NLP_EVT_NOTHING_PENDING;
 				lpfc_issue_els_plogi(vport, ndlp->nlp_DID, 0);
+			} else {
+				clear_bit(NLP_UNREG_INP, &ndlp->nlp_flag);
 			}
 
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