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From:   Karan Tilak Kumar <kartilak@cisco.com>
To:     sebaddel@cisco.com
Cc:     arulponn@cisco.com, djhawar@cisco.com, gcboffa@cisco.com,
        mkai2@cisco.com, satishkh@cisco.com, jejb@linux.ibm.com,
        martin.petersen@oracle.com, linux-scsi@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Karan Tilak Kumar <kartilak@cisco.com>
Subject: [PATCH v2 11/13] scsi: fnic: Use fnic_lock to protect fnic structures in queuecommand
Date:   Fri, 27 Oct 2023 11:03:00 -0700
Message-Id: <20231027180302.418676-12-kartilak@cisco.com>
In-Reply-To: <20231027180302.418676-1-kartilak@cisco.com>
References: <20231027180302.418676-1-kartilak@cisco.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

fnic does not use host_lock. fnic uses fnic_lock.
Use fnic lock to protect fnic members in fnic_queuecommand.
Add log messages in error cases.

Reviewed-by: Sesidhar Baddela <sebaddel@cisco.com>
Reviewed-by: Arulprabhu Ponnusamy <arulponn@cisco.com>
Signed-off-by: Karan Tilak Kumar <kartilak@cisco.com>
---
 drivers/scsi/fnic/fnic_scsi.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c
index 9a1beb3e7269..ffdbdbfcdf57 100644
--- a/drivers/scsi/fnic/fnic_scsi.c
+++ b/drivers/scsi/fnic/fnic_scsi.c
@@ -424,14 +424,27 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc)
 	int io_lock_acquired = 0;
 	struct fc_rport_libfc_priv *rp;
 
-	if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_IO_BLOCKED)))
+	spin_lock_irqsave(&fnic->fnic_lock, flags);
+
+	if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_IO_BLOCKED))) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
+		FNIC_SCSI_DBG(KERN_ERR, fnic->lport->host,
+			"fnic<%d>: %s: %d: fnic IO blocked flags: 0x%lx. Returning SCSI_MLQUEUE_HOST_BUSY\n",
+			fnic->fnic_num, __func__, __LINE__, fnic->state_flags);
 		return SCSI_MLQUEUE_HOST_BUSY;
+	}
 
-	if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_FWRESET)))
+	if (unlikely(fnic_chk_state_flags_locked(fnic, FNIC_FLAGS_FWRESET))) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
+		FNIC_SCSI_DBG(KERN_ERR, fnic->lport->host,
+			"fnic<%d>: %s: %d: fnic flags: 0x%lx. Returning SCSI_MLQUEUE_HOST_BUSY\n",
+			fnic->fnic_num, __func__, __LINE__, fnic->state_flags);
 		return SCSI_MLQUEUE_HOST_BUSY;
+	}
 
 	rport = starget_to_rport(scsi_target(sc->device));
 	if (!rport) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
 		FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
 				"returning DID_NO_CONNECT for IO as rport is NULL\n");
 		sc->result = DID_NO_CONNECT << 16;
@@ -441,6 +454,7 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc)
 
 	ret = fc_remote_port_chkready(rport);
 	if (ret) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
 		FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
 				"rport is not ready\n");
 		atomic64_inc(&fnic_stats->misc_stats.rport_not_ready);
@@ -451,6 +465,7 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc)
 
 	rp = rport->dd_data;
 	if (!rp || rp->rp_state == RPORT_ST_DELETE) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
 		FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
 			"rport 0x%x removed, returning DID_NO_CONNECT\n",
 			rport->port_id);
@@ -462,6 +477,7 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc)
 	}
 
 	if (rp->rp_state != RPORT_ST_READY) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
 		FNIC_SCSI_DBG(KERN_DEBUG, fnic->lport->host,
 			"rport 0x%x in state 0x%x, returning DID_IMM_RETRY\n",
 			rport->port_id, rp->rp_state);
@@ -471,11 +487,17 @@ static int fnic_queuecommand_lck(struct scsi_cmnd *sc)
 		return 0;
 	}
 
-	if (lp->state != LPORT_ST_READY || !(lp->link_up))
+	if (lp->state != LPORT_ST_READY || !(lp->link_up)) {
+		spin_unlock_irqrestore(&fnic->fnic_lock, flags);
+		FNIC_SCSI_DBG(KERN_ERR, fnic->lport->host,
+			"fnic<%d>: %s: %d: state not ready: %d/link not up: %d Returning HOST_BUSY\n",
+			fnic->fnic_num, __func__, __LINE__, lp->state, lp->link_up);
 		return SCSI_MLQUEUE_HOST_BUSY;
+	}
 
 	atomic_inc(&fnic->in_flight);
 
+	spin_unlock_irqrestore(&fnic->fnic_lock, flags);
 	fnic_priv(sc)->state = FNIC_IOREQ_NOT_INITED;
 	fnic_priv(sc)->flags = FNIC_NO_FLAGS;
 
-- 
2.31.1