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 7c20823..646feb4 100644
--- a/include/net/smc.h
+++ b/include/net/smc.h
@@ -79,6 +79,8 @@
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 d79dd78..30854ac 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -276,6 +276,7 @@
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 @@
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 @@
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 56cdab8..5c4727d 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -302,6 +302,7 @@
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) {
