From: James Smart <jsmart2021@gmail.com>
Date: Mon, 5 Mar 2018 12:04:07 -0800
Subject: [PATCH] scsi: lpfc: Fix mailbox wait for POST_SGL mbox command
Patch-mainline: v4.17-rc1
Git-commit: e29d74f8eb1450b0b6c4736210d76cb56ef40e1d
References: bsc#1085387

POST_SGL_PAGES mailbox command failed with status (timeout).

wait_event_interruptible_timeout when called from mailbox wait interface,
gets interrupted, and will randomly fail. Behavior seems very specific to 1
particular server type.

Fix by changing from wait_event_interruptible_timeout to
wait_for_completion_timeout.

Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
---
 drivers/scsi/lpfc/lpfc_sli.c | 34 ++++++++++++----------------------
 drivers/scsi/lpfc/lpfc_sli.h |  1 +
 2 files changed, 13 insertions(+), 22 deletions(-)

diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c
index 7999a40e1370..1a9083adef1f 100644
--- a/drivers/scsi/lpfc/lpfc_sli.c
+++ b/drivers/scsi/lpfc/lpfc_sli.c
@@ -2388,18 +2388,18 @@ lpfc_sli_chk_mbx_command(uint8_t mbxCommand)
 void
 lpfc_sli_wake_mbox_wait(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmboxq)
 {
-	wait_queue_head_t *pdone_q;
 	unsigned long drvr_flag;
+	struct completion *pmbox_done;
 
 	/*
-	 * If pdone_q is empty, the driver thread gave up waiting and
+	 * If pmbox_done is empty, the driver thread gave up waiting and
 	 * continued running.
 	 */
 	pmboxq->mbox_flag |= LPFC_MBX_WAKE;
 	spin_lock_irqsave(&phba->hbalock, drvr_flag);
-	pdone_q = (wait_queue_head_t *) pmboxq->context1;
-	if (pdone_q)
-		wake_up_interruptible(pdone_q);
+	pmbox_done = (struct completion *)pmboxq->context3;
+	if (pmbox_done)
+		complete(pmbox_done);
 	spin_unlock_irqrestore(&phba->hbalock, drvr_flag);
 	return;
 }
@@ -11665,31 +11665,25 @@ int
 lpfc_sli_issue_mbox_wait(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmboxq,
 			 uint32_t timeout)
 {
-	DECLARE_WAIT_QUEUE_HEAD_ONSTACK(done_q);
-	MAILBOX_t *mb = NULL;
+	struct completion mbox_done;
 	int retval;
 	unsigned long flag;
 
-	/* The caller might set context1 for extended buffer */
-	if (pmboxq->context1)
-		mb = (MAILBOX_t *)pmboxq->context1;
-
 	pmboxq->mbox_flag &= ~LPFC_MBX_WAKE;
 	/* setup wake call as IOCB callback */
 	pmboxq->mbox_cmpl = lpfc_sli_wake_mbox_wait;
-	/* setup context field to pass wait_queue pointer to wake function  */
-	pmboxq->context1 = &done_q;
 
+	/* setup context3 field to pass wait_queue pointer to wake function  */
+	init_completion(&mbox_done);
+	pmboxq->context3 = &mbox_done;
 	/* now issue the command */
 	retval = lpfc_sli_issue_mbox(phba, pmboxq, MBX_NOWAIT);
 	if (retval == MBX_BUSY || retval == MBX_SUCCESS) {
-		wait_event_interruptible_timeout(done_q,
-				pmboxq->mbox_flag & LPFC_MBX_WAKE,
-				msecs_to_jiffies(timeout * 1000));
+		wait_for_completion_timeout(&mbox_done,
+					    msecs_to_jiffies(timeout * 1000));
 
 		spin_lock_irqsave(&phba->hbalock, flag);
-		/* restore the possible extended buffer for free resource */
-		pmboxq->context1 = (uint8_t *)mb;
+		pmboxq->context3 = NULL;
 		/*
 		 * if LPFC_MBX_WAKE flag is set the mailbox is completed
 		 * else do not free the resources.
@@ -11701,11 +11695,7 @@ lpfc_sli_issue_mbox_wait(struct lpfc_hba *phba, LPFC_MBOXQ_t *pmboxq,
 			pmboxq->mbox_cmpl = lpfc_sli_def_mbox_cmpl;
 		}
 		spin_unlock_irqrestore(&phba->hbalock, flag);
-	} else {
-		/* restore the possible extended buffer for free resource */
-		pmboxq->context1 = (uint8_t *)mb;
 	}
-
 	return retval;
 }
 
diff --git a/drivers/scsi/lpfc/lpfc_sli.h b/drivers/scsi/lpfc/lpfc_sli.h
index ad7b2e0a2018..431754195505 100644
--- a/drivers/scsi/lpfc/lpfc_sli.h
+++ b/drivers/scsi/lpfc/lpfc_sli.h
@@ -147,6 +147,7 @@ typedef struct lpfcMboxq {
 	struct lpfc_vport *vport;/* virtual port pointer */
 	void *context1;		/* caller context information */
 	void *context2;		/* caller context information */
+	void *context3;
 
 	void (*mbox_cmpl) (struct lpfc_hba *, struct lpfcMboxq *);
 	uint8_t mbox_flag;
-- 
2.12.3