net/smc: delete link processing as SMC server

Add smc_llc_process_srv_delete_link() to process a DELETE_LINK request
as SMC server. When the request is to delete ALL links then terminate
the whole link group. If not, find the link to delete by its link_id,
send the DELETE_LINK request LLC message and wait for the response.
No matter if a response was received, clear the deleted link and update
the link group state.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index cd57b4f..ac065f6 100644 (file)
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -1187,6 +1187,76 @@ out:
        kfree(qentry);
 }
 
+static void smc_llc_process_srv_delete_link(struct smc_link_group *lgr)
+{
+       struct smc_llc_msg_del_link *del_llc;
+       struct smc_link *lnk, *lnk_del;
+       struct smc_llc_qentry *qentry;
+       int active_links;
+       int i;
+
+       mutex_lock(&lgr->llc_conf_mutex);
+       qentry = smc_llc_flow_qentry_clr(&lgr->llc_flow_lcl);
+       lnk = qentry->link;
+       del_llc = &qentry->msg.delete_link;
+
+       if (qentry->msg.delete_link.hd.flags & SMC_LLC_FLAG_DEL_LINK_ALL) {
+               /* delete entire lgr */
+               smc_lgr_terminate_sched(lgr);
+               goto out;
+       }
+       /* delete single link */
+       lnk_del = NULL;
+       for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
+               if (lgr->lnk[i].link_id == del_llc->link_num) {
+                       lnk_del = &lgr->lnk[i];
+                       break;
+               }
+       }
+       if (!lnk_del)
+               goto out; /* asymmetric link already deleted */
+
+       if (smc_link_downing(&lnk_del->state)) {
+               /* tbd: call smc_switch_conns(lgr, lnk_del, false); */
+               smc_wr_tx_wait_no_pending_sends(lnk_del);
+       }
+       if (!list_empty(&lgr->list)) {
+               /* qentry is either a request from peer (send it back to
+                * initiate the DELETE_LINK processing), or a locally
+                * enqueued DELETE_LINK request (forward it)
+                */
+               if (!smc_llc_send_message(lnk, &qentry->msg)) {
+                       struct smc_llc_msg_del_link *del_llc_resp;
+                       struct smc_llc_qentry *qentry2;
+
+                       qentry2 = smc_llc_wait(lgr, lnk, SMC_LLC_WAIT_TIME,
+                                              SMC_LLC_DELETE_LINK);
+                       if (!qentry2) {
+                       } else {
+                               del_llc_resp = &qentry2->msg.delete_link;
+                               smc_llc_flow_qentry_del(&lgr->llc_flow_lcl);
+                       }
+               }
+       }
+       smcr_link_clear(lnk_del);
+
+       active_links = smc_llc_active_link_count(lgr);
+       if (active_links == 1) {
+               lgr->type = SMC_LGR_SINGLE;
+       } else if (!active_links) {
+               lgr->type = SMC_LGR_NONE;
+               smc_lgr_terminate_sched(lgr);
+       }
+
+       if (lgr->type == SMC_LGR_SINGLE && !list_empty(&lgr->list)) {
+               /* trigger setup of asymm alt link */
+               /* tbd: call smc_llc_srv_add_link_local(lnk); */
+       }
+out:
+       mutex_unlock(&lgr->llc_conf_mutex);
+       kfree(qentry);
+}
+
 static void smc_llc_delete_link_work(struct work_struct *work)
 {
        struct smc_link_group *lgr = container_of(work, struct smc_link_group,
@@ -1200,6 +1270,8 @@ static void smc_llc_delete_link_work(struct work_struct *work)
 
        if (lgr->role == SMC_CLNT)
                smc_llc_process_cli_delete_link(lgr);
+       else
+               smc_llc_process_srv_delete_link(lgr);
 out:
        smc_llc_flow_stop(lgr, &lgr->llc_flow_lcl);
 }