net/smc: add SMC-D shutdown signal

When a SMC-D link group is freed, a shutdown signal should be sent to
the peer to indicate that the link group is invalid. This patch adds the
shutdown signal to the SMC code.

Signed-off-by: Hans Wippel <hwippel@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 43 insertions, 14 deletions

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 3c023de58afd..1c9fa7f0261a 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -184,6 +184,8 @@ free:
 
                 if (!lgr->is_smcd && lnk->state != SMC_LNK_INACTIVE)
                         smc_llc_link_inactive(lnk);
+                if (lgr->is_smcd)
+                        smc_ism_signal_shutdown(lgr);
                 smc_lgr_free(lgr);
         }
 }
@@ -485,7 +487,7 @@ void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport)
 }
 
 /* Called when SMC-D device is terminated or peer is lost */
-void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid)
+void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
 {
         struct smc_link_group *lgr, *l;
         LIST_HEAD(lgr_free_list);
@@ -495,7 +497,7 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid)
         list_for_each_entry_safe(lgr, l, &smc_lgr_list.list, list) {
                 if (lgr->is_smcd && lgr->smcd == dev &&
                     (!peer_gid || lgr->peer_gid == peer_gid) &&
-                    !list_empty(&lgr->list)) {
+                    (vlan == VLAN_VID_MASK || lgr->vlan_id == vlan)) {
                         __smc_lgr_terminate(lgr);
                         list_move(&lgr->list, &lgr_free_list);
                 }
@@ -506,6 +508,8 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid)
         list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
                 list_del_init(&lgr->list);
                 cancel_delayed_work_sync(&lgr->free_work);
+                if (!peer_gid && vlan == VLAN_VID_MASK) /* dev terminated? */
+                        smc_ism_signal_shutdown(lgr);
                 smc_lgr_free(lgr);
         }
 }
@@ -1026,6 +1030,8 @@ void smc_core_exit(void)
                         smc_llc_link_inactive(lnk);
                 }
                 cancel_delayed_work_sync(&lgr->free_work);
+                if (lgr->is_smcd)
+                        smc_ism_signal_shutdown(lgr);
                 smc_lgr_free(lgr); /* free link group */
         }
 }
diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 5bc6cbaf0ed5..cf98f4d6093e 100644
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -247,7 +247,8 @@ void smc_lgr_free(struct smc_link_group *lgr);
 void smc_lgr_forget(struct smc_link_group *lgr);
 void smc_lgr_terminate(struct smc_link_group *lgr);
 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
-void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid);
+void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
+                        unsigned short vlan);
 int smc_buf_create(struct smc_sock *smc, bool is_smcd);
 int smc_uncompress_bufsize(u8 compressed);
 int smc_rmb_rtoken_handling(struct smc_connection *conn,
diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index e36f21ce7252..2fff79db1a59 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -187,22 +187,28 @@ struct smc_ism_event_work {
 #define ISM_EVENT_REQUEST               0x0001
 #define ISM_EVENT_RESPONSE              0x0002
 #define ISM_EVENT_REQUEST_IR            0x00000001
+#define ISM_EVENT_CODE_SHUTDOWN         0x80
 #define ISM_EVENT_CODE_TESTLINK         0x83
 
+union smcd_sw_event_info {
+        u64     info;
+        struct {
+                u8              uid[SMC_LGR_ID_SIZE];
+                unsigned short  vlan_id;
+                u16             code;
+        };
+};
+
 static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
 {
-        union {
-                u64     info;
-                struct {
-                        u32             uid;
-                        unsigned short  vlanid;
-                        u16             code;
-                };
-        } ev_info;
+        union smcd_sw_event_info ev_info;
 
+        ev_info.info = wrk->event.info;
         switch (wrk->event.code) {
+        case ISM_EVENT_CODE_SHUTDOWN:   /* Peer shut down DMBs */
+                smc_smcd_terminate(wrk->smcd, wrk->event.tok, ev_info.vlan_id);
+                break;
         case ISM_EVENT_CODE_TESTLINK:   /* Activity timer */
-                ev_info.info = wrk->event.info;
                 if (ev_info.code == ISM_EVENT_REQUEST) {
                         ev_info.code = ISM_EVENT_RESPONSE;
                         wrk->smcd->ops->signal_event(wrk->smcd,
@@ -215,6 +221,21 @@ static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
         }
 }
 
+int smc_ism_signal_shutdown(struct smc_link_group *lgr)
+{
+        int rc;
+        union smcd_sw_event_info ev_info;
+
+        memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
+        ev_info.vlan_id = lgr->vlan_id;
+        ev_info.code = ISM_EVENT_REQUEST;
+        rc = lgr->smcd->ops->signal_event(lgr->smcd, lgr->peer_gid,
+                                          ISM_EVENT_REQUEST_IR,
+                                          ISM_EVENT_CODE_SHUTDOWN,
+                                          ev_info.info);
+        return rc;
+}
+
 /* worker for SMC-D events */
 static void smc_ism_event_work(struct work_struct *work)
 {
@@ -223,7 +244,7 @@ static void smc_ism_event_work(struct work_struct *work)
 
         switch (wrk->event.type) {
         case ISM_EVENT_GID:     /* GID event, token is peer GID */
-                smc_smcd_terminate(wrk->smcd, wrk->event.tok);
+                smc_smcd_terminate(wrk->smcd, wrk->event.tok, VLAN_VID_MASK);
                 break;
         case ISM_EVENT_DMB:
                 break;
@@ -289,7 +310,7 @@ void smcd_unregister_dev(struct smcd_dev *smcd)
         spin_unlock(&smcd_dev_list.lock);
         flush_workqueue(smcd->event_wq);
         destroy_workqueue(smcd->event_wq);
-        smc_smcd_terminate(smcd, 0);
+        smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);
 
         device_del(&smcd->dev);
 }
diff --git a/net/smc/smc_ism.h b/net/smc/smc_ism.h
index aee45b860b79..4da946cbfa29 100644
--- a/net/smc/smc_ism.h
+++ b/net/smc/smc_ism.h
@@ -45,4 +45,5 @@ int smc_ism_register_dmb(struct smc_link_group *lgr, int buf_size,
 int smc_ism_unregister_dmb(struct smcd_dev *dev, struct smc_buf_desc *dmb_desc);
 int smc_ism_write(struct smcd_dev *dev, const struct smc_ism_position *pos,
                   void *data, size_t len);
+int smc_ism_signal_shutdown(struct smc_link_group *lgr);
 #endif