[SCSI] libfc: add support of receiving ELS_RLS

Upon receiving ELS_RLS, send the Link Error Status Block (LESB) back.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 76 insertions, 0 deletions

diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c
index 91e2ba27f7bd..35ca0e72df46 100644
--- a/drivers/scsi/libfc/fc_rport.c
+++ b/drivers/scsi/libfc/fc_rport.c
@@ -1098,6 +1098,78 @@ drop:
 }
 
 /**
+ * fc_rport_recv_rls_req() - Handle received Read Link Status request
+ * @rdata: The remote port that sent the RLS request
+ * @sp: The sequence that the RLS was on
+ * @rx_fp: The PRLI request frame
+ *
+ * Locking Note: The rport lock is expected to be held before calling
+ * this function.
+ */
+static void fc_rport_recv_rls_req(struct fc_rport_priv *rdata,
+                                  struct fc_seq *sp, struct fc_frame *rx_fp)
+
+{
+        struct fc_lport *lport = rdata->local_port;
+        struct fc_frame *fp;
+        struct fc_exch *ep = fc_seq_exch(sp);
+        struct fc_els_rls *rls;
+        struct fc_els_rls_resp *rsp;
+        struct fc_els_lesb *lesb;
+        struct fc_seq_els_data rjt_data;
+        struct fc_host_statistics *hst;
+        u32 f_ctl;
+
+        FC_RPORT_DBG(rdata, "Received RLS request while in state %s\n",
+                     fc_rport_state(rdata));
+
+        rls = fc_frame_payload_get(rx_fp, sizeof(*rls));
+        if (!rls) {
+                rjt_data.reason = ELS_RJT_PROT;
+                rjt_data.explan = ELS_EXPL_INV_LEN;
+                goto out_rjt;
+        }
+
+        fp = fc_frame_alloc(lport, sizeof(*rsp));
+        if (!fp) {
+                rjt_data.reason = ELS_RJT_UNAB;
+                rjt_data.explan = ELS_EXPL_INSUF_RES;
+                goto out_rjt;
+        }
+
+        rsp = fc_frame_payload_get(fp, sizeof(*rsp));
+        memset(rsp, 0, sizeof(*rsp));
+        rsp->rls_cmd = ELS_LS_ACC;
+        lesb = &rsp->rls_lesb;
+        if (lport->tt.get_lesb) {
+                /* get LESB from LLD if it supports it */
+                lport->tt.get_lesb(lport, lesb);
+        } else {
+                fc_get_host_stats(lport->host);
+                hst = &lport->host_stats;
+                lesb->lesb_link_fail = htonl(hst->link_failure_count);
+                lesb->lesb_sync_loss = htonl(hst->loss_of_sync_count);
+                lesb->lesb_sig_loss = htonl(hst->loss_of_signal_count);
+                lesb->lesb_prim_err = htonl(hst->prim_seq_protocol_err_count);
+                lesb->lesb_inv_word = htonl(hst->invalid_tx_word_count);
+                lesb->lesb_inv_crc = htonl(hst->invalid_crc_count);
+        }
+
+        sp = lport->tt.seq_start_next(sp);
+        f_ctl = FC_FC_EX_CTX | FC_FC_LAST_SEQ | FC_FC_END_SEQ;
+        fc_fill_fc_hdr(fp, FC_RCTL_ELS_REP, ep->did, ep->sid,
+                       FC_TYPE_ELS, f_ctl, 0);
+        lport->tt.seq_send(lport, sp, fp);
+        goto out;
+
+out_rjt:
+        rjt_data.fp = NULL;
+        lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data);
+out:
+        fc_frame_free(rx_fp);
+}
+
+/**
  * fc_rport_recv_els_req() - Handler for validated ELS requests
  * @lport: The local port that received the ELS request
  * @sp:    The sequence that the ELS request was on
@@ -1159,6 +1231,9 @@ static void fc_rport_recv_els_req(struct fc_lport *lport,
                 els_data.fp = fp;
                 lport->tt.seq_els_rsp_send(sp, ELS_REC, &els_data);
                 break;
+        case ELS_RLS:
+                fc_rport_recv_rls_req(rdata, sp, fp);
+                break;
         default:
                 fc_frame_free(fp);      /* can't happen */
                 break;
@@ -1203,6 +1278,7 @@ void fc_rport_recv_req(struct fc_seq *sp, struct fc_frame *fp,
         case ELS_ADISC:
         case ELS_RRQ:
         case ELS_REC:
+        case ELS_RLS:
                 fc_rport_recv_els_req(lport, sp, fp);
                 break;
         default: