[SCSI] libfc: improve flogi retries to avoid lport stuck

Adds more cases to do flogi retry, now also retry
on getting bad response due to either no ELS response
or flogi response payload length not large enough.
In those cases flogi was not retried and that
was leaving lport offline.

Signed-off-by: Vasu Dev <vasu.dev@intel.com>
Tested-by: Bhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 49 insertions, 41 deletions

diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c
index e0fb8913356..2cb12b9cd3e 100644
--- a/drivers/scsi/libfc/fc_lport.c
+++ b/drivers/scsi/libfc/fc_lport.c
@@ -1473,6 +1473,7 @@ void fc_lport_flogi_resp(struct fc_seq *sp, struct fc_frame *fp,
 			 void *lp_arg)
 {
 	struct fc_lport *lport = lp_arg;
+	struct fc_frame_header *fh;
 	struct fc_els_flogi *flp;
 	u32 did;
 	u16 csp_flags;
@@ -1500,49 +1501,56 @@ void fc_lport_flogi_resp(struct fc_seq *sp, struct fc_frame *fp,
 		goto err;
 	}
 
+	fh = fc_frame_header_get(fp);
 	did = fc_frame_did(fp);
-	if (fc_frame_payload_op(fp) == ELS_LS_ACC && did) {
-		flp = fc_frame_payload_get(fp, sizeof(*flp));
-		if (flp) {
-			mfs = ntohs(flp->fl_csp.sp_bb_data) &
-				FC_SP_BB_DATA_MASK;
-			if (mfs >= FC_SP_MIN_MAX_PAYLOAD &&
-			    mfs < lport->mfs)
-				lport->mfs = mfs;
-			csp_flags = ntohs(flp->fl_csp.sp_features);
-			r_a_tov = ntohl(flp->fl_csp.sp_r_a_tov);
-			e_d_tov = ntohl(flp->fl_csp.sp_e_d_tov);
-			if (csp_flags & FC_SP_FT_EDTR)
-				e_d_tov /= 1000000;
-
-			lport->npiv_enabled = !!(csp_flags & FC_SP_FT_NPIV_ACC);
-
-			if ((csp_flags & FC_SP_FT_FPORT) == 0) {
-				if (e_d_tov > lport->e_d_tov)
-					lport->e_d_tov = e_d_tov;
-				lport->r_a_tov = 2 * e_d_tov;
-				fc_lport_set_port_id(lport, did, fp);
-				printk(KERN_INFO "host%d: libfc: "
-				       "Port (%6.6x) entered "
-				       "point-to-point mode\n",
-				       lport->host->host_no, did);
-				fc_lport_ptp_setup(lport, fc_frame_sid(fp),
-						   get_unaligned_be64(
-							   &flp->fl_wwpn),
-						   get_unaligned_be64(
-							   &flp->fl_wwnn));
-			} else {
-				lport->e_d_tov = e_d_tov;
-				lport->r_a_tov = r_a_tov;
-				fc_host_fabric_name(lport->host) =
-					get_unaligned_be64(&flp->fl_wwnn);
-				fc_lport_set_port_id(lport, did, fp);
-				fc_lport_enter_dns(lport);
-			}
-		}
-	} else {
-		FC_LPORT_DBG(lport, "FLOGI RJT or bad response\n");
+	if (fh->fh_r_ctl != FC_RCTL_ELS_REP || did == 0 ||
+	    fc_frame_payload_op(fp) != ELS_LS_ACC) {
+		FC_LPORT_DBG(lport, "FLOGI not accepted or bad response\n");
 		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	flp = fc_frame_payload_get(fp, sizeof(*flp));
+	if (!flp) {
+		FC_LPORT_DBG(lport, "FLOGI bad response\n");
+		fc_lport_error(lport, fp);
+		goto err;
+	}
+
+	mfs = ntohs(flp->fl_csp.sp_bb_data) &
+		FC_SP_BB_DATA_MASK;
+	if (mfs >= FC_SP_MIN_MAX_PAYLOAD &&
+	    mfs < lport->mfs)
+		lport->mfs = mfs;
+	csp_flags = ntohs(flp->fl_csp.sp_features);
+	r_a_tov = ntohl(flp->fl_csp.sp_r_a_tov);
+	e_d_tov = ntohl(flp->fl_csp.sp_e_d_tov);
+	if (csp_flags & FC_SP_FT_EDTR)
+		e_d_tov /= 1000000;
+
+	lport->npiv_enabled = !!(csp_flags & FC_SP_FT_NPIV_ACC);
+
+	if ((csp_flags & FC_SP_FT_FPORT) == 0) {
+		if (e_d_tov > lport->e_d_tov)
+			lport->e_d_tov = e_d_tov;
+		lport->r_a_tov = 2 * e_d_tov;
+		fc_lport_set_port_id(lport, did, fp);
+		printk(KERN_INFO "host%d: libfc: "
+		       "Port (%6.6x) entered "
+		       "point-to-point mode\n",
+		       lport->host->host_no, did);
+		fc_lport_ptp_setup(lport, fc_frame_sid(fp),
+				   get_unaligned_be64(
+					   &flp->fl_wwpn),
+				   get_unaligned_be64(
+					   &flp->fl_wwnn));
+	} else {
+		lport->e_d_tov = e_d_tov;
+		lport->r_a_tov = r_a_tov;
+		fc_host_fabric_name(lport->host) =
+			get_unaligned_be64(&flp->fl_wwnn);
+		fc_lport_set_port_id(lport, did, fp);
+		fc_lport_enter_dns(lport);
 	}
 
 out: