[SCSI] zfcp: Decouple gid_pn requests from erp

Don't let the erp wait for gid_pn requests to complete. Instead, queue
the gid_pn work, exit erp and let the finished gid_pn work trigger a
new port reopen.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

6 files changed, 47 insertions, 56 deletions

diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index ed7211ef04eb..572dcd67e713 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -362,6 +362,11 @@ static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
         if (!adapter->pool.erp_req)
                 return -ENOMEM;
 
+        adapter->pool.gid_pn_req =
+                mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
+        if (!adapter->pool.gid_pn_req)
+                return -ENOMEM;
+
         adapter->pool.scsi_req =
                 mempool_create_kmalloc_pool(1, sizeof(struct zfcp_fsf_req));
         if (!adapter->pool.scsi_req)
@@ -379,7 +384,7 @@ static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
                 return -ENOMEM;
 
         adapter->pool.qtcb_pool =
-                mempool_create_slab_pool(3, zfcp_data.qtcb_cache);
+                mempool_create_slab_pool(4, zfcp_data.qtcb_cache);
         if (!adapter->pool.qtcb_pool)
                 return -ENOMEM;
 
@@ -652,7 +657,7 @@ struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
 
         init_waitqueue_head(&port->remove_wq);
         INIT_LIST_HEAD(&port->unit_list_head);
-        INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
+        INIT_WORK(&port->gid_pn_work, zfcp_fc_port_did_lookup);
         INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
         INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
 
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index bac5c497eab5..9a8ff0553421 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -265,6 +265,7 @@ struct zfcp_fsf_req;
 /* holds various memory pools of an adapter */
 struct zfcp_adapter_mempool {
         mempool_t *erp_req;
+        mempool_t *gid_pn_req;
         mempool_t *scsi_req;
         mempool_t *scsi_abort;
         mempool_t *status_read_req;
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index feda1db56b23..67297d2744fb 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -26,7 +26,6 @@ enum zfcp_erp_steps {
         ZFCP_ERP_STEP_FSF_XCONFIG       = 0x0001,
         ZFCP_ERP_STEP_PHYS_PORT_CLOSING = 0x0010,
         ZFCP_ERP_STEP_PORT_CLOSING      = 0x0100,
-        ZFCP_ERP_STEP_NAMESERVER_LOOKUP = 0x0400,
         ZFCP_ERP_STEP_PORT_OPENING      = 0x0800,
         ZFCP_ERP_STEP_UNIT_CLOSING      = 0x1000,
         ZFCP_ERP_STEP_UNIT_OPENING      = 0x2000,
@@ -842,27 +841,6 @@ static int zfcp_erp_open_ptp_port(struct zfcp_erp_action *act)
         return zfcp_erp_port_strategy_open_port(act);
 }
 
-void zfcp_erp_port_strategy_open_lookup(struct work_struct *work)
-{
-        int retval;
-        struct zfcp_port *port = container_of(work, struct zfcp_port,
-                                              gid_pn_work);
-
-        retval = zfcp_fc_ns_gid_pn(&port->erp_action);
-        if (!retval) {
-                port->erp_action.step = ZFCP_ERP_STEP_NAMESERVER_LOOKUP;
-                goto out;
-        }
-        if (retval == -ENOMEM) {
-                zfcp_erp_notify(&port->erp_action, ZFCP_STATUS_ERP_LOWMEM);
-                goto out;
-        }
-        /* all other error condtions */
-        zfcp_erp_notify(&port->erp_action, 0);
-out:
-        zfcp_port_put(port);
-}
-
 static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
 {
         struct zfcp_adapter *adapter = act->adapter;
@@ -880,12 +858,8 @@ static int zfcp_erp_port_strategy_open_common(struct zfcp_erp_action *act)
                         if (!queue_work(adapter->work_queue,
                                         &port->gid_pn_work))
                                 zfcp_port_put(port);
-                        return ZFCP_ERP_CONTINUES;
+                        return ZFCP_ERP_EXIT;
                 }
-                /* fall through */
-        case ZFCP_ERP_STEP_NAMESERVER_LOOKUP:
-                if (!port->d_id)
-                        return ZFCP_ERP_FAILED;
                 return zfcp_erp_port_strategy_open_port(act);
 
         case ZFCP_ERP_STEP_PORT_OPENING:
diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h
index e97947d2f2ed..7650cec7f71f 100644
--- a/drivers/s390/scsi/zfcp_ext.h
+++ b/drivers/s390/scsi/zfcp_ext.h
@@ -94,13 +94,12 @@ extern void zfcp_erp_unit_access_denied(struct zfcp_unit *, char *, void *);
 extern void zfcp_erp_adapter_access_changed(struct zfcp_adapter *, char *,
                                             void *);
 extern void zfcp_erp_timeout_handler(unsigned long);
-extern void zfcp_erp_port_strategy_open_lookup(struct work_struct *);
 
 /* zfcp_fc.c */
 extern int zfcp_scan_ports(struct zfcp_adapter *);
 extern void _zfcp_scan_ports_later(struct work_struct *);
 extern void zfcp_fc_incoming_els(struct zfcp_fsf_req *);
-extern int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *);
+extern void zfcp_fc_port_did_lookup(struct work_struct *);
 extern void zfcp_fc_plogi_evaluate(struct zfcp_port *, struct fsf_plogi *);
 extern void zfcp_test_link(struct zfcp_port *);
 extern void zfcp_fc_link_test_work(struct work_struct *);
@@ -128,8 +127,7 @@ extern struct zfcp_fsf_req *zfcp_fsf_control_file(struct zfcp_adapter *,
 extern void zfcp_fsf_req_dismiss_all(struct zfcp_adapter *);
 extern int zfcp_fsf_status_read(struct zfcp_qdio *);
 extern int zfcp_status_read_refill(struct zfcp_adapter *adapter);
-extern int zfcp_fsf_send_ct(struct zfcp_send_ct *, mempool_t *,
-                            struct zfcp_erp_action *);
+extern int zfcp_fsf_send_ct(struct zfcp_send_ct *, mempool_t *);
 extern int zfcp_fsf_send_els(struct zfcp_send_els *);
 extern int zfcp_fsf_send_fcp_command_task(struct zfcp_unit *,
                                           struct scsi_cmnd *);
diff --git a/drivers/s390/scsi/zfcp_fc.c b/drivers/s390/scsi/zfcp_fc.c
index 8921e16fdab7..bc0c9f54d0d8 100644
--- a/drivers/s390/scsi/zfcp_fc.c
+++ b/drivers/s390/scsi/zfcp_fc.c
@@ -282,15 +282,15 @@ static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
 }
 
-int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
+static int zfcp_fc_ns_gid_pn_request(struct zfcp_port *port,
                                      struct zfcp_gid_pn_data *gid_pn)
 {
-        struct zfcp_adapter *adapter = erp_action->adapter;
+        struct zfcp_adapter *adapter = port->adapter;
         struct zfcp_fc_ns_handler_data compl_rec;
         int ret;
 
         /* setup parameters for send generic command */
-        gid_pn->port = erp_action->port;
+        gid_pn->port = port;
         gid_pn->ct.wka_port = &adapter->gs->ds;
         gid_pn->ct.handler = zfcp_fc_ns_handler;
         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
@@ -309,12 +309,12 @@ int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
         gid_pn->ct_iu_req.header.options = ZFCP_CT_SYNCHRONOUS;
         gid_pn->ct_iu_req.header.cmd_rsp_code = ZFCP_CT_GID_PN;
         gid_pn->ct_iu_req.header.max_res_size = ZFCP_CT_SIZE_ONE_PAGE / 4;
-        gid_pn->ct_iu_req.wwpn = erp_action->port->wwpn;
+        gid_pn->ct_iu_req.wwpn = port->wwpn;
 
         init_completion(&compl_rec.done);
         compl_rec.handler = zfcp_fc_ns_gid_pn_eval;
         compl_rec.handler_data = (unsigned long) gid_pn;
-        ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.erp_req, erp_action);
+        ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.gid_pn_req);
         if (!ret)
                 wait_for_completion(&compl_rec.done);
         return ret;
@@ -322,14 +322,14 @@ int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
 
 /**
  * zfcp_fc_ns_gid_pn_request - initiate GID_PN nameserver request
- * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
+ * @port: port where GID_PN request is needed
  * return: -ENOMEM on error, 0 otherwise
  */
-int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
+static int zfcp_fc_ns_gid_pn(struct zfcp_port *port)
 {
         int ret;
         struct zfcp_gid_pn_data *gid_pn;
-        struct zfcp_adapter *adapter = erp_action->adapter;
+        struct zfcp_adapter *adapter = port->adapter;
 
         gid_pn = mempool_alloc(adapter->pool.gid_pn_data, GFP_ATOMIC);
         if (!gid_pn)
@@ -341,7 +341,7 @@ int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
         if (ret)
                 goto out;
 
-        ret = zfcp_fc_ns_gid_pn_request(erp_action, gid_pn);
+        ret = zfcp_fc_ns_gid_pn_request(port, gid_pn);
 
         zfcp_wka_port_put(&adapter->gs->ds);
 out:
@@ -349,6 +349,29 @@ out:
         return ret;
 }
 
+void zfcp_fc_port_did_lookup(struct work_struct *work)
+{
+        int ret;
+        struct zfcp_port *port = container_of(work, struct zfcp_port,
+                                              gid_pn_work);
+
+        ret = zfcp_fc_ns_gid_pn(port);
+        if (ret) {
+                /* could not issue gid_pn for some reason */
+                zfcp_erp_adapter_reopen(port->adapter, 0, "fcgpn_1", NULL);
+                goto out;
+        }
+
+        if (!port->d_id) {
+                zfcp_erp_port_failed(port, "fcgpn_2", NULL);
+                goto out;
+        }
+
+        zfcp_erp_port_reopen(port, 0, "fcgpn_3", NULL);
+out:
+        zfcp_port_put(port);
+}
+
 /**
  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
  * @port: zfcp_port structure
@@ -551,7 +574,7 @@ static int zfcp_scan_issue_gpn_ft(struct zfcp_gpn_ft *gpn_ft,
 
         init_completion(&compl_rec.done);
         compl_rec.handler = NULL;
-        ret = zfcp_fsf_send_ct(ct, NULL, NULL);
+        ret = zfcp_fsf_send_ct(ct, NULL);
         if (!ret)
                 wait_for_completion(&compl_rec.done);
         return ret;
@@ -840,7 +863,7 @@ int zfcp_fc_execute_ct_fc_job(struct fc_bsg_job *job)
         ct_fc_job->ct.completion = NULL;
         ct_fc_job->job = job;
 
-        ret = zfcp_fsf_send_ct(&ct_fc_job->ct, NULL, NULL);
+        ret = zfcp_fsf_send_ct(&ct_fc_job->ct, NULL);
         if (ret) {
                 kfree(ct_fc_job);
                 zfcp_wka_port_put(ct_fc_job->ct.wka_port);
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index b9a16e4b48b4..048f1a848f34 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -1069,10 +1069,8 @@ static int zfcp_fsf_setup_ct_els_sbals(struct zfcp_fsf_req *req,
  * zfcp_fsf_send_ct - initiate a Generic Service request (FC-GS)
  * @ct: pointer to struct zfcp_send_ct with data for request
  * @pool: if non-null this mempool is used to allocate struct zfcp_fsf_req
- * @erp_action: if non-null the Generic Service request sent within ERP
  */
-int zfcp_fsf_send_ct(struct zfcp_send_ct *ct, mempool_t *pool,
-                     struct zfcp_erp_action *erp_action)
+int zfcp_fsf_send_ct(struct zfcp_send_ct *ct, mempool_t *pool)
 {
         struct zfcp_wka_port *wka_port = ct->wka_port;
         struct zfcp_qdio *qdio = wka_port->adapter->qdio;
@@ -1103,13 +1101,7 @@ int zfcp_fsf_send_ct(struct zfcp_send_ct *ct, mempool_t *pool,
         req->data = ct;
 
         zfcp_san_dbf_event_ct_request(req);
-
-        if (erp_action) {
-                erp_action->fsf_req = req;
-                req->erp_action = erp_action;
-                zfcp_fsf_start_erp_timer(req);
-        } else
-                zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
+        zfcp_fsf_start_timer(req, ZFCP_FSF_REQUEST_TIMEOUT);
 
         ret = zfcp_fsf_req_send(req);
         if (ret)
@@ -1119,8 +1111,6 @@ int zfcp_fsf_send_ct(struct zfcp_send_ct *ct, mempool_t *pool,
 
 failed_send:
         zfcp_fsf_req_free(req);
-        if (erp_action)
-                erp_action->fsf_req = NULL;
 out:
         spin_unlock_bh(&qdio->req_q_lock);
         return ret;