From d5b45dd5ba6c944b17118530843e67bf9c096e49 Mon Sep 17 00:00:00 2001

From: Brian King <brking@linux.vnet.ibm.com>

Date: Tue, 11 May 2021 13:12:18 -0500

Subject: [PATCH] scsi: ibmvfc: Handle move login failure

References: bsc#1185938 ltc#192043

Patch-mainline: queued

Git-repo: git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi.git

Git-commit: d5b45dd5ba6c944b17118530843e67bf9c096e49

When service is being performed on an SVC with NPIV enabled, the WWPN of

the canister / node being serviced fails over to the another canister /

node. This looks to the ibmvfc driver as a WWPN moving from one SCSI ID to

another. The driver will first attempt to do an implicit logout of the old

SCSI ID. If this works, we simply delete the rport at the old location and

add an rport at the new location and the FC transport class handles

everything. However, if there is I/O outstanding, this implicit logout will

fail, in which case we will send a "move login" request to the VIOS. This

will cancel any outstanding I/O to that port, logout the port, and PLOGI

the new port. Recently we've encountered a scenario where the move login

fails. This was resulting in an attempted plogi to the new scsi id, without

the old scsi id getting logged out, which is a VIOS protocol violation. To

solve this, we want to keep tracking the old scsi id as the current scsi

id. That way, once terminate_rport_io cancels the outstanding i/o, it will

send us back through to do an implicit logout of the old scsi id, rather

than the new scsi id, and then we can plogi the new scsi id.

Link: https://lore.kernel.org/r/1620756740-7045-2-git-send-email-brking@linux.vnet.ibm.com

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Acked-by: Michal Suchanek <msuchanek@suse.de>

---

 drivers/scsi/ibmvscsi/ibmvfc.c | 16 ++++++++--------

 drivers/scsi/ibmvscsi/ibmvfc.h |  2 +-

 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.c b/drivers/scsi/ibmvscsi/ibmvfc.c

index 6540d48eb0e8..4ac5bff69305 100644

--- a/drivers/scsi/ibmvscsi/ibmvfc.c

+++ b/drivers/scsi/ibmvscsi/ibmvfc.c

@@ -4299,9 +4299,10 @@ static void ibmvfc_tgt_move_login_done(struct ibmvfc_event *evt)

 	ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_NONE);

 	switch (status) {

 	case IBMVFC_MAD_SUCCESS:

-		tgt_dbg(tgt, "Move Login succeeded for old scsi_id: %llX\n", tgt->old_scsi_id);

+		tgt_dbg(tgt, "Move Login succeeded for new scsi_id: %llX\n", tgt->new_scsi_id);

 		tgt->ids.node_name = wwn_to_u64(rsp->service_parms.node_name);

 		tgt->ids.port_name = wwn_to_u64(rsp->service_parms.port_name);

+		tgt->scsi_id = tgt->new_scsi_id;

 		tgt->ids.port_id = tgt->scsi_id;

 		memcpy(&tgt->service_parms, &rsp->service_parms,

 		       sizeof(tgt->service_parms));

@@ -4319,8 +4320,8 @@ static void ibmvfc_tgt_move_login_done(struct ibmvfc_event *evt)

 		level += ibmvfc_retry_tgt_init(tgt, ibmvfc_tgt_move_login);

 		tgt_log(tgt, level,

-			"Move Login failed: old scsi_id: %llX, flags:%x, vios_flags:%x, rc=0x%02X\n",

-			tgt->old_scsi_id, be32_to_cpu(rsp->flags), be16_to_cpu(rsp->vios_flags),

+			"Move Login failed: new scsi_id: %llX, flags:%x, vios_flags:%x, rc=0x%02X\n",

+			tgt->new_scsi_id, be32_to_cpu(rsp->flags), be16_to_cpu(rsp->vios_flags),

 			status);

 		break;

 	}

@@ -4357,8 +4358,8 @@ static void ibmvfc_tgt_move_login(struct ibmvfc_target *tgt)

 	move->common.opcode = cpu_to_be32(IBMVFC_MOVE_LOGIN);

 	move->common.length = cpu_to_be16(sizeof(*move));

-	move->old_scsi_id = cpu_to_be64(tgt->old_scsi_id);

-	move->new_scsi_id = cpu_to_be64(tgt->scsi_id);

+	move->old_scsi_id = cpu_to_be64(tgt->scsi_id);

+	move->new_scsi_id = cpu_to_be64(tgt->new_scsi_id);

 	move->wwpn = cpu_to_be64(tgt->wwpn);

 	move->node_name = cpu_to_be64(tgt->ids.node_name);

@@ -4367,7 +4368,7 @@ static void ibmvfc_tgt_move_login(struct ibmvfc_target *tgt)

 		ibmvfc_set_tgt_action(tgt, IBMVFC_TGT_ACTION_DEL_RPORT);

 		kref_put(&tgt->kref, ibmvfc_release_tgt);

 	} else

-		tgt_dbg(tgt, "Sent Move Login for old scsi_id: %llX\n", tgt->old_scsi_id);

+		tgt_dbg(tgt, "Sent Move Login for new scsi_id: %llX\n", tgt->new_scsi_id);

 }

 /**

@@ -4737,8 +4738,7 @@ static int ibmvfc_alloc_target(struct ibmvfc_host *vhost,

 			 * normal ibmvfc_set_tgt_action to set this, as we

 			 * don't normally want to allow this state change.

 			 */

-			wtgt->old_scsi_id = wtgt->scsi_id;

-			wtgt->scsi_id = scsi_id;

+			wtgt->new_scsi_id = scsi_id;

 			wtgt->action = IBMVFC_TGT_ACTION_INIT;

 			ibmvfc_init_tgt(wtgt, ibmvfc_tgt_move_login);

 			goto unlock_out;

diff --git a/drivers/scsi/ibmvscsi/ibmvfc.h b/drivers/scsi/ibmvscsi/ibmvfc.h

index 19dcec3ae9ba..4601bd21372d 100644

--- a/drivers/scsi/ibmvscsi/ibmvfc.h

+++ b/drivers/scsi/ibmvscsi/ibmvfc.h

@@ -718,7 +718,7 @@ struct ibmvfc_target {

 	struct ibmvfc_host *vhost;

 	u64 scsi_id;

 	u64 wwpn;

-	u64 old_scsi_id;

+	u64 new_scsi_id;

 	struct fc_rport *rport;

 	int target_id;

 	enum ibmvfc_target_action action;

-- 

2.26.2