net/smc: introduce bookkeeping of SMCD link groups

If the ism module is unloaded return control from exit routine only,
if all link groups are freed.
If an IB device is thrown away return control from device removal only,
if all link groups belonging to this device are freed.
A counters for the total number of SMCD link groups per ISM device is
introduced. ism module unloading continues only if the total number of
SMCD link groups for all ISM devices is zero. ISM device
removal continues only it the total number of SMCD link groups per ISM
device has decreased to zero.

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/include/net/smc.h b/include/net/smc.h
index 7c2082341bb34fa13957a648f486b12ef11c575f..646feb4bc75f2bb0f38170104eda0ae52d56322a 100644 (file)
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -79,6 +79,8 @@ struct smcd_dev {
        bool pnetid_by_user;
        struct list_head lgr_list;
        spinlock_t lgr_lock;
+       atomic_t lgr_cnt;
+       wait_queue_head_t lgrs_deleted;
        u8 going_away : 1;
 };
 

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index d79dd78c1cd871c7b4229843c9e9966ee7f23fff..30854acb846c5031fe7041ff7240e48afc3388ac 100644 (file)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -276,6 +276,7 @@ static int smc_lgr_create(struct smc_sock *smc, struct smc_init_info *ini)
                lgr_list = &ini->ism_dev->lgr_list;
                lgr_lock = &lgr->smcd->lgr_lock;
                lgr->peer_shutdown = 0;
+               atomic_inc(&ini->ism_dev->lgr_cnt);
        } else {
                /* SMC-R specific settings */
                get_device(&ini->ib_dev->ibdev->dev);
@@ -486,6 +487,8 @@ static void smc_lgr_free(struct smc_link_group *lgr)
                        smc_ism_put_vlan(lgr->smcd, lgr->vlan_id);
                        put_device(&lgr->smcd->dev);
                }
+               if (!atomic_dec_return(&lgr->smcd->lgr_cnt))
+                       wake_up(&lgr->smcd->lgrs_deleted);
        } else {
                smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]);
                put_device(&lgr->lnk[SMC_SINGLE_LINK].smcibdev->ibdev->dev);
@@ -685,6 +688,9 @@ void smc_smcd_terminate_all(struct smcd_dev *smcd)
                list_del_init(&lgr->list);
                __smc_lgr_terminate(lgr, false);
        }
+
+       if (atomic_read(&smcd->lgr_cnt))
+               wait_event(smcd->lgrs_deleted, !atomic_read(&smcd->lgr_cnt));
 }
 
 /* Determine vlan of internal TCP socket.

diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index 56cdab8be1fa2e90b5a0b3152cf7ac96fb059203..5c4727d5066e82156651c6143601bbea0525015d 100644 (file)
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -302,6 +302,7 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
        spin_lock_init(&smcd->lgr_lock);
        INIT_LIST_HEAD(&smcd->vlan);
        INIT_LIST_HEAD(&smcd->lgr_list);
+       init_waitqueue_head(&smcd->lgrs_deleted);
        smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
                                                 WQ_MEM_RECLAIM, name);
        if (!smcd->event_wq) {