[PATCH 1/6] mpt fusion - fibre channel target discovery prematurely terminates

[Michael Reed <mdr@xxxxxxx>]

mpt_config() can return EAGAIN.  When this happens, fibre channel target
discovery can prematurely terminate with fewer than the total number of
targets discovered.  This patch detects EAGAIN and reschedules the scan
work.

Generally, this situation only occurs when the lsiutil program is being
used to reset the board.

Signed-off-by: Michael Reed <mdr@xxxxxxx>



mpt_config() can return EAGAIN.  When this happens, fibre channel target
discovery can prematurely terminate with fewer than the total number of
targets discovered.  This patch detects EAGAIN and reschedules the scan
work.

Generally, this situation only occurs when the lsiutil program is being
used to reset the board.

Signed-off-by: Michael Reed <mdr@xxxxxxx>


--- rc3u/drivers/message/fusion/mptfc.c	2006-05-01 16:06:13.311966423 -0500
+++ rc3/drivers/message/fusion/mptfc.c	2006-05-03 14:16:47.669834844 -0500
@@ -634,6 +634,7 @@
 	MPT_ADAPTER		*ioc = (MPT_ADAPTER *)arg;
 	int			ii;
 	int			work_to_do;
+	int			rc=0;
 	u64			pn;
 	unsigned long		flags;
 	struct mptfc_rport_info *ri;
@@ -651,9 +652,13 @@
 		 * will reregister existing rports
 		 */
 		for (ii=0; ii < ioc->facts.NumberOfPorts; ii++) {
-			(void) mptbase_GetFcPortPage0(ioc, ii);
+			rc = mptbase_GetFcPortPage0(ioc, ii);
+			if (rc == -EAGAIN)
+				break;
 			mptfc_init_host_attr(ioc,ii);	/* refresh */
-			mptfc_GetFcDevPage0(ioc,ii,mptfc_register_dev);
+			rc = mptfc_GetFcDevPage0(ioc,ii,mptfc_register_dev);
+			if (rc == -EAGAIN)
+				break;
 		}
 
 		/* delete devices still missing */
@@ -686,6 +691,20 @@
 		work_to_do = --ioc->fc_rescan_work_count;
 		spin_unlock_irqrestore(&ioc->fc_rescan_work_lock, flags);
 	} while (work_to_do);
+
+	/* if last pass failed with EAGAIN, reschedule work for a later attempt */
+	if (rc == -EAGAIN) {
+		spin_lock_irqsave(&ioc->fc_rescan_work_lock, flags);
+		if (ioc->fc_rescan_work_q) {
+			queue_delayed_work(ioc->fc_rescan_work_q, &ioc->fc_rescan_work, HZ);
+			ioc->fc_rescan_work_count = 1;
+		}
+		spin_unlock_irqrestore(&ioc->fc_rescan_work_lock, flags);
+		dfcprintk ((MYIOC_s_INFO_FMT
+			"mptfc_rescan.%d: rescheduling work\n",
+			ioc->name,
+			ioc->sh->host_no));
+	}
 }
 
 static int
@@ -981,6 +1000,7 @@
 		spin_lock_irqsave(&ioc->fc_rescan_work_lock, flags);
 		ioc->fc_rescan_work_q = NULL;
 		spin_unlock_irqrestore(&ioc->fc_rescan_work_lock, flags);
+		cancel_delayed_work(&ioc->fc_rescan_work);
 		destroy_workqueue(work_q);
 	}