6 files changed, 32 insertions, 35 deletions

diff --git a/drivers/s390/scsi/zfcp_aux.c b/drivers/s390/scsi/zfcp_aux.c
index d23027a2f2f..41635b13ccb 100644
--- a/drivers/s390/scsi/zfcp_aux.c
+++ b/drivers/s390/scsi/zfcp_aux.c
@@ -970,6 +970,27 @@ static void zfcp_dummy_release(struct device *dev)
         return;
 }
 
+int zfcp_status_read_refill(struct zfcp_adapter *adapter)
+{
+        while (atomic_read(&adapter->stat_miss) > 0)
+                if (zfcp_fsf_status_read(adapter, ZFCP_WAIT_FOR_SBAL))
+                        break;
+        else
+                atomic_dec(&adapter->stat_miss);
+
+        if (ZFCP_STATUS_READS_RECOM <= atomic_read(&adapter->stat_miss)) {
+                zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
+                return 1;
+        }
+        return 0;
+}
+
+static void _zfcp_status_read_scheduler(struct work_struct *work)
+{
+        zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
+                                             stat_work));
+}
+
 /*
  * Enqueues an adapter at the end of the adapter list in the driver data.
  * All adapter internal structures are set up.
@@ -1063,6 +1084,7 @@ zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 
         /* initialize lock of associated request queue */
         rwlock_init(&adapter->request_queue.queue_lock);
+        INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
 
         /* mark adapter unusable as long as sysfs registration is not complete */
         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
@@ -1123,6 +1145,7 @@ zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
         int retval = 0;
         unsigned long flags;
 
+        cancel_work_sync(&adapter->stat_work);
         zfcp_adapter_scsi_unregister(adapter);
         device_unregister(&adapter->generic_services);
         zfcp_sysfs_adapter_remove_files(&adapter->ccw_device->dev);
diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c
index c8bad675dbd..1710c12a32c 100644
--- a/drivers/s390/scsi/zfcp_dbf.c
+++ b/drivers/s390/scsi/zfcp_dbf.c
@@ -268,7 +268,7 @@ void zfcp_hba_dbf_event_fsf_unsol(const char *tag, struct zfcp_adapter *adapter,
         strncpy(rec->tag, "stat", ZFCP_DBF_TAG_SIZE);
         strncpy(rec->tag2, tag, ZFCP_DBF_TAG_SIZE);
 
-        rec->u.status.failed = adapter->status_read_failed;
+        rec->u.status.failed = atomic_read(&adapter->stat_miss);
         if (status_buffer != NULL) {
                 rec->u.status.status_type = status_buffer->status_type;
                 rec->u.status.status_subtype = status_buffer->status_subtype;
diff --git a/drivers/s390/scsi/zfcp_def.h b/drivers/s390/scsi/zfcp_def.h
index 306fcd0cae3..adfbbb07448 100644
--- a/drivers/s390/scsi/zfcp_def.h
+++ b/drivers/s390/scsi/zfcp_def.h
@@ -136,7 +136,6 @@ zfcp_address_to_sg(void *address, struct scatterlist *list, unsigned int size)
 #define ZFCP_QTCB_VERSION       FSF_QTCB_CURRENT_VERSION
 /* ATTENTION: value must not be used by hardware */
 #define FSF_QTCB_UNSOLICITED_STATUS             0x6305
-#define ZFCP_STATUS_READ_FAILED_THRESHOLD       3
 #define ZFCP_STATUS_READS_RECOM                 FSF_STATUS_READS_RECOM
 
 /* Do 1st retry in 1 second, then double the timeout for each following retry */
@@ -759,7 +758,8 @@ struct zfcp_adapter {
         rwlock_t                abort_lock;        /* Protects against SCSI
                                                       stack abort/command
                                                       completion races */
-        u16                     status_read_failed; /* # failed status reads */
+        atomic_t                stat_miss;         /* # missing status reads*/
+        struct work_struct      stat_work;
         atomic_t                status;            /* status of this adapter */
         struct list_head        erp_ready_head;    /* error recovery for this
                                                       adapter/devices */
diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c
index 805484658dd..55a4fdc4262 100644
--- a/drivers/s390/scsi/zfcp_erp.c
+++ b/drivers/s390/scsi/zfcp_erp.c
@@ -2139,25 +2139,10 @@ static int
 zfcp_erp_adapter_strategy_open_fsf_statusread(struct zfcp_erp_action
                                               *erp_action)
 {
-        int retval = ZFCP_ERP_SUCCEEDED;
-        int temp_ret;
         struct zfcp_adapter *adapter = erp_action->adapter;
-        int i;
 
-        adapter->status_read_failed = 0;
-        for (i = 0; i < ZFCP_STATUS_READS_RECOM; i++) {
-                temp_ret = zfcp_fsf_status_read(adapter, ZFCP_WAIT_FOR_SBAL);
-                if (temp_ret < 0) {
-                        ZFCP_LOG_INFO("error: set-up of unsolicited status "
-                                      "notification failed on adapter %s\n",
-                                      zfcp_get_busid_by_adapter(adapter));
-                        retval = ZFCP_ERP_FAILED;
-                        i--;
-                        break;
-                }
-        }
-
-        return retval;
+        atomic_set(&adapter->stat_miss, 16);
+        return zfcp_status_read_refill(adapter);
 }
 
 /*
diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h
index 6abf178fda5..250565794fa 100644
--- a/drivers/s390/scsi/zfcp_ext.h
+++ b/drivers/s390/scsi/zfcp_ext.h
@@ -92,6 +92,7 @@ extern void zfcp_fsf_start_timer(struct zfcp_fsf_req *, unsigned long);
 extern void zfcp_erp_start_timer(struct zfcp_fsf_req *);
 extern void zfcp_fsf_req_dismiss_all(struct zfcp_adapter *);
 extern int  zfcp_fsf_status_read(struct zfcp_adapter *, int);
+extern int zfcp_status_read_refill(struct zfcp_adapter *adapter);
 extern int zfcp_fsf_req_create(struct zfcp_adapter *, u32, int, mempool_t *,
                                unsigned long *, struct zfcp_fsf_req **);
 extern int zfcp_fsf_send_ct(struct zfcp_send_ct *, mempool_t *,
diff --git a/drivers/s390/scsi/zfcp_fsf.c b/drivers/s390/scsi/zfcp_fsf.c
index 1e7136483c1..b344e8a72f1 100644
--- a/drivers/s390/scsi/zfcp_fsf.c
+++ b/drivers/s390/scsi/zfcp_fsf.c
@@ -1029,21 +1029,9 @@ zfcp_fsf_status_read_handler(struct zfcp_fsf_req *fsf_req)
          * FIXME:
          * allocation failure possible? (Is this code needed?)
          */
-        retval = zfcp_fsf_status_read(adapter, 0);
-        if (retval < 0) {
-                ZFCP_LOG_INFO("Failed to create unsolicited status read "
-                              "request for the adapter %s.\n",
-                              zfcp_get_busid_by_adapter(adapter));
-                /* temporary fix to avoid status read buffer shortage */
-                adapter->status_read_failed++;
-                if ((ZFCP_STATUS_READS_RECOM - adapter->status_read_failed)
-                    < ZFCP_STATUS_READ_FAILED_THRESHOLD) {
-                        ZFCP_LOG_INFO("restart adapter %s due to status read "
-                                      "buffer shortage\n",
-                                      zfcp_get_busid_by_adapter(adapter));
-                        zfcp_erp_adapter_reopen(adapter, 0, 103, fsf_req);
-                }
-        }
+
+        atomic_inc(&adapter->stat_miss);
+        schedule_work(&adapter->stat_work);
  out:
         return retval;
 }