net/smc: abnormal termination of SMCD link groups

A final cleanup due to SMCD device removal means immediate freeing
of all link groups belonging to this device in interrupt context.

This patch introduces a separate SMCD link group termination routine,
which terminates all link groups of an SMCD device.

This new routine smcd_terminate_all ()is reused if the smc module is
unloaded.

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

diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c
index 49bcebf..0879f7b 100644 (file)
--- a/net/smc/smc_clc.c
+++ b/net/smc/smc_clc.c
@@ -349,7 +349,7 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen,
                smc->peer_diagnosis = ntohl(dclc->peer_diagnosis);
                if (((struct smc_clc_msg_decline *)buf)->hdr.flag) {
                        smc->conn.lgr->sync_err = 1;
-                       smc_lgr_terminate(smc->conn.lgr);
+                       smc_lgr_terminate(smc->conn.lgr, true);
                }
        }
 

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 9d6da2c..d79dd78 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -224,7 +224,7 @@ static void smc_lgr_terminate_work(struct work_struct *work)
        struct smc_link_group *lgr = container_of(work, struct smc_link_group,
                                                  terminate_work);
 
-       smc_lgr_terminate(lgr);
+       smc_lgr_terminate(lgr, true);
 }
 
 /* create a new SMC link group */
@@ -528,7 +528,7 @@ static void smc_sk_wake_ups(struct smc_sock *smc)
 }
 
 /* kill a connection */
-static void smc_conn_kill(struct smc_connection *conn)
+static void smc_conn_kill(struct smc_connection *conn, bool soft)
 {
        struct smc_sock *smc = container_of(conn, struct smc_sock, conn);
 
@@ -541,7 +541,10 @@ static void smc_conn_kill(struct smc_connection *conn)
        smc_sk_wake_ups(smc);
        if (conn->lgr->is_smcd) {
                smc_ism_unset_conn(conn);
-               tasklet_kill(&conn->rx_tsklet);
+               if (soft)
+                       tasklet_kill(&conn->rx_tsklet);
+               else
+                       tasklet_unlock_wait(&conn->rx_tsklet);
        }
        smc_lgr_unregister_conn(conn);
        smc_close_active_abort(smc);
@@ -562,7 +565,7 @@ static void smc_lgr_cleanup(struct smc_link_group *lgr)
 }
 
 /* terminate link group */
-static void __smc_lgr_terminate(struct smc_link_group *lgr)
+static void __smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
 {
        struct smc_connection *conn;
        struct smc_sock *smc;
@@ -570,6 +573,8 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr)
 
        if (lgr->terminating)
                return; /* lgr already terminating */
+       if (!soft)
+               cancel_delayed_work_sync(&lgr->free_work);
        lgr->terminating = 1;
        if (!lgr->is_smcd)
                smc_llc_link_inactive(&lgr->lnk[SMC_SINGLE_LINK]);
@@ -583,7 +588,7 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr)
                smc = container_of(conn, struct smc_sock, conn);
                sock_hold(&smc->sk); /* sock_put below */
                lock_sock(&smc->sk);
-               smc_conn_kill(conn);
+               smc_conn_kill(conn, soft);
                release_sock(&smc->sk);
                sock_put(&smc->sk); /* sock_hold above */
                read_lock_bh(&lgr->conns_lock);
@@ -591,11 +596,17 @@ static void __smc_lgr_terminate(struct smc_link_group *lgr)
        }
        read_unlock_bh(&lgr->conns_lock);
        smc_lgr_cleanup(lgr);
-       smc_lgr_schedule_free_work_fast(lgr);
+       if (soft)
+               smc_lgr_schedule_free_work_fast(lgr);
+       else
+               smc_lgr_free(lgr);
 }
 
-/* unlink and terminate link group */
-void smc_lgr_terminate(struct smc_link_group *lgr)
+/* unlink and terminate link group
+ * @soft: true if link group shutdown can take its time
+ *       false if immediate link group shutdown is required
+ */
+void smc_lgr_terminate(struct smc_link_group *lgr, bool soft)
 {
        spinlock_t *lgr_lock;
 
@@ -605,9 +616,11 @@ void smc_lgr_terminate(struct smc_link_group *lgr)
                spin_unlock_bh(lgr_lock);
                return; /* lgr already terminating */
        }
+       if (!soft)
+               lgr->freeing = 1;
        list_del_init(&lgr->list);
        spin_unlock_bh(lgr_lock);
-       __smc_lgr_terminate(lgr);
+       __smc_lgr_terminate(lgr, soft);
 }
 
 /* Called when IB port is terminated */
@@ -627,11 +640,11 @@ void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport)
 
        list_for_each_entry_safe(lgr, l, &lgr_free_list, list) {
                list_del_init(&lgr->list);
-               __smc_lgr_terminate(lgr);
+               __smc_lgr_terminate(lgr, true);
        }
 }
 
-/* Called when SMC-D device is terminated or peer is lost */
+/* Called when peer lgr shutdown (regularly or abnormally) is received */
 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
 {
        struct smc_link_group *lgr, *l;
@@ -656,6 +669,24 @@ void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid, unsigned short vlan)
        }
 }
 
+/* Called when an SMCD device is removed or the smc module is unloaded */
+void smc_smcd_terminate_all(struct smcd_dev *smcd)
+{
+       struct smc_link_group *lgr, *lg;
+       LIST_HEAD(lgr_free_list);
+
+       spin_lock_bh(&smcd->lgr_lock);
+       list_splice_init(&smcd->lgr_list, &lgr_free_list);
+       list_for_each_entry(lgr, &lgr_free_list, list)
+               lgr->freeing = 1;
+       spin_unlock_bh(&smcd->lgr_lock);
+
+       list_for_each_entry_safe(lgr, lg, &lgr_free_list, list) {
+               list_del_init(&lgr->list);
+               __smc_lgr_terminate(lgr, false);
+       }
+}
+
 /* Determine vlan of internal TCP socket.
  * @vlan_id: address to store the determined vlan id into
  */
@@ -1173,8 +1204,8 @@ static void smc_core_going_away(void)
        spin_unlock(&smcd_dev_list.lock);
 }
 
-/* Called (from smc_exit) when module is removed */
-void smc_core_exit(void)
+/* Clean up all SMC link groups */
+static void smc_lgrs_shutdown(void)
 {
        struct smc_link_group *lgr, *lg;
        LIST_HEAD(lgr_freeing_list);
@@ -1188,7 +1219,7 @@ void smc_core_exit(void)
 
        spin_lock(&smcd_dev_list.lock);
        list_for_each_entry(smcd, &smcd_dev_list.list, list)
-               list_splice_init(&smcd->lgr_list, &lgr_freeing_list);
+               smc_smcd_terminate_all(smcd);
        spin_unlock(&smcd_dev_list.lock);
 
        list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) {
@@ -1202,8 +1233,12 @@ 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 */
        }
 }
+
+/* Called (from smc_exit) when module is removed */
+void smc_core_exit(void)
+{
+       smc_lgrs_shutdown();
+}

diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h
index 097ceba..7f34f4d 100644 (file)
--- a/net/smc/smc_core.h
+++ b/net/smc/smc_core.h
@@ -296,10 +296,11 @@ struct smc_clc_msg_accept_confirm;
 struct smc_clc_msg_local;
 
 void smc_lgr_forget(struct smc_link_group *lgr);
-void smc_lgr_terminate(struct smc_link_group *lgr);
+void smc_lgr_terminate(struct smc_link_group *lgr, bool soft);
 void smc_port_terminate(struct smc_ib_device *smcibdev, u8 ibport);
 void smc_smcd_terminate(struct smcd_dev *dev, u64 peer_gid,
                        unsigned short vlan);
+void smc_smcd_terminate_all(struct smcd_dev *dev);
 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 903da94..56cdab8 100644 (file)
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -329,7 +329,7 @@ void smcd_unregister_dev(struct smcd_dev *smcd)
        list_del_init(&smcd->list);
        spin_unlock(&smcd_dev_list.lock);
        smcd->going_away = 1;
-       smc_smcd_terminate(smcd, 0, VLAN_VID_MASK);
+       smc_smcd_terminate_all(smcd);
        flush_workqueue(smcd->event_wq);
        destroy_workqueue(smcd->event_wq);
 

diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c
index e1918ff..26a18c8 100644 (file)
--- a/net/smc/smc_llc.c
+++ b/net/smc/smc_llc.c
@@ -614,7 +614,7 @@ static void smc_llc_testlink_work(struct work_struct *work)
        rc = wait_for_completion_interruptible_timeout(&link->llc_testlink_resp,
                                                       SMC_LLC_WAIT_TIME);
        if (rc <= 0) {
-               smc_lgr_terminate(smc_get_lgr(link));
+               smc_lgr_terminate(smc_get_lgr(link), true);
                return;
        }
        next_interval = link->llc_testlink_time;

diff --git a/net/smc/smc_tx.c b/net/smc/smc_tx.c
index 824f096..0d42e77 100644 (file)
--- a/net/smc/smc_tx.c
+++ b/net/smc/smc_tx.c
@@ -284,7 +284,7 @@ static int smc_tx_rdma_write(struct smc_connection *conn, int peer_rmbe_offset,
        rdma_wr->rkey = lgr->rtokens[conn->rtoken_idx][SMC_SINGLE_LINK].rkey;
        rc = ib_post_send(link->roce_qp, &rdma_wr->wr, NULL);
        if (rc)
-               smc_lgr_terminate(lgr);
+               smc_lgr_terminate(lgr, true);
        return rc;
 }