[patch 03/11] zfcp: Adapter reopen for large number of unsolicited status

Christof Schmitt
2008-07-02T09:00:05Z

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From: Swen Schillig <swen@vnet.ibm.com>

When zfcp receives 16 unsolicited status messages, this could trigger
an adapter reopen. In this case, first try to send a new status read,
and only if this fails, go through the recovery.

Signed-off-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
---
drivers/s390/scsi/zfcp_aux.c | 15 +++++++--------
drivers/s390/scsi/zfcp_def.h | 3 +--
2 files changed, 8 insertions(+), 10 deletions(-)

--- a/drivers/s390/scsi/zfcp_aux.c 2008-06-27 18:06:59.000000000 +0200
+++ b/drivers/s390/scsi/zfcp_aux.c 2008-06-27 18:07:57.000000000 +0200
@@ -550,15 +550,14 @@ static void zfcp_dummy_release(struct de
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))
+ if (zfcp_fsf_status_read(adapter, ZFCP_WAIT_FOR_SBAL)) {
+ if (atomic_read(&adapter->stat_miss) >= 16) {
+ zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
+ return 1;
+ }
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;
- }
+ } else
+ atomic_dec(&adapter->stat_miss);
return 0;
}

--- a/drivers/s390/scsi/zfcp_def.h 2008-06-27 18:06:59.000000000 +0200
+++ b/drivers/s390/scsi/zfcp_def.h 2008-06-27 18:07:57.000000000 +0200
@@ -108,7 +108,6 @@ zfcp_address_to_sg(void *address, struct
#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_READS_RECOM FSF_STATUS_READS_RECOM

/* Do 1st retry in 1 second, then double the timeout for each following retry */
#define ZFCP_EXCHANGE_CONFIG_DATA_FIRST_SLEEP 1
@@ -743,7 +742,7 @@ struct zfcp_data {
#define ZFCP_POOL_FSF_REQ_ERP_NR 1
#define ZFCP_POOL_FSF_REQ_SCSI_NR 1
#define ZFCP_POOL_FSF_REQ_ABORT_NR 1
-#define ZFCP_POOL_STATUS_READ_NR ZFCP_STATUS_READS_RECOM
+#define ZFCP_POOL_STATUS_READ_NR FSF_STATUS_READS_RECOM
#define ZFCP_POOL_DATA_GID_PN_NR 1

/* struct used by memory pools for fsf_requests */

--