@@ -1338,7 +1338,6 @@ static int pass_accept_req(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
struct iwch_ep *child_ep, *parent_ep = ctx;
struct cpl_pass_accept_req *req = cplhdr(skb);
unsigned int hwtid = GET_TID(req);
- struct neighbour *neigh;
struct dst_entry *dst;
struct l2t_entry *l2t;
struct rtable *rt;
@@ -1375,10 +1374,7 @@ static int pass_accept_req(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
goto reject;
}
dst = &rt->dst;
- rcu_read_lock();
- neigh = dst_get_neighbour_noref(dst);
- l2t = t3_l2t_get(tdev, neigh, neigh->dev);
- rcu_read_unlock();
+ l2t = t3_l2t_get(tdev, dst, NULL);
if (!l2t) {
printk(KERN_ERR MOD "%s - failed to allocate l2t entry!\n",
__func__);
@@ -1889,7 +1885,6 @@ static int is_loopback_dst(struct iw_cm_id *cm_id)
int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
{
struct iwch_dev *h = to_iwch_dev(cm_id->device);
- struct neighbour *neigh;
struct iwch_ep *ep;
struct rtable *rt;
int err = 0;
@@ -1947,13 +1942,7 @@ int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
goto fail3;
}
ep->dst = &rt->dst;
-
- rcu_read_lock();
- neigh = dst_get_neighbour_noref(ep->dst);
-
- /* get a l2t entry */
- ep->l2t = t3_l2t_get(ep->com.tdev, neigh, neigh->dev);
- rcu_read_unlock();
+ ep->l2t = t3_l2t_get(ep->com.tdev, ep->dst, NULL);
if (!ep->l2t) {
printk(KERN_ERR MOD "%s - cannot alloc l2e.\n", __func__);
err = -ENOMEM;
@@ -1132,7 +1132,7 @@ static void cxgb_redirect(struct dst_entry *old, struct dst_entry *new)
}
/* Add new L2T entry */
- e = t3_l2t_get(tdev, dst_get_neighbour_noref(new), newdev);
+ e = t3_l2t_get(tdev, new, newdev);
if (!e) {
printk(KERN_ERR "%s: couldn't allocate new l2t entry!\n",
__func__);
@@ -298,18 +298,31 @@ static inline void reuse_entry(struct l2t_entry *e, struct neighbour *neigh)
spin_unlock(&e->lock);
}
-struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
+struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct dst_entry *dst,
struct net_device *dev)
{
struct l2t_entry *e = NULL;
+ struct neighbour *neigh;
+ struct port_info *p;
struct l2t_data *d;
int hash;
- u32 addr = *(u32 *) neigh->primary_key;
- int ifidx = neigh->dev->ifindex;
- struct port_info *p = netdev_priv(dev);
- int smt_idx = p->port_id;
+ u32 addr;
+ int ifidx;
+ int smt_idx;
rcu_read_lock();
+ neigh = dst_get_neighbour_noref(dst);
+ if (!neigh)
+ goto done_rcu;
+
+ addr = *(u32 *) neigh->primary_key;
+ ifidx = neigh->dev->ifindex;
+
+ if (!dev)
+ dev = neigh->dev;
+ p = netdev_priv(dev);
+ smt_idx = p->port_id;
+
d = L2DATA(cdev);
if (!d)
goto done_rcu;
@@ -323,7 +336,7 @@ struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
l2t_hold(d, e);
if (atomic_read(&e->refcnt) == 1)
reuse_entry(e, neigh);
- goto done;
+ goto done_unlock;
}
/* Need to allocate a new entry */
@@ -344,7 +357,7 @@ struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
e->vlan = VLAN_NONE;
spin_unlock(&e->lock);
}
-done:
+done_unlock:
write_unlock_bh(&d->lock);
done_rcu:
rcu_read_unlock();
@@ -109,7 +109,7 @@ static inline void set_arp_failure_handler(struct sk_buff *skb,
void t3_l2e_free(struct l2t_data *d, struct l2t_entry *e);
void t3_l2t_update(struct t3cdev *dev, struct neighbour *neigh);
-struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct neighbour *neigh,
+struct l2t_entry *t3_l2t_get(struct t3cdev *cdev, struct dst_entry *dst,
struct net_device *dev);
int t3_l2t_send_slow(struct t3cdev *dev, struct sk_buff *skb,
struct l2t_entry *e);
@@ -966,7 +966,7 @@ static int init_act_open(struct cxgbi_sock *csk)
csk->saddr.sin_addr.s_addr = chba->ipv4addr;
csk->rss_qid = 0;
- csk->l2t = t3_l2t_get(t3dev, dst_get_neighbour_noref(dst), ndev);
+ csk->l2t = t3_l2t_get(t3dev, dst, ndev);
if (!csk->l2t) {
pr_err("NO l2t available.\n");
return -EINVAL;
This way we consolidate the RCU locking down into the place where it actually matters, and also we can make the code handle dst_get_neighbour_noref() returning NULL properly. Signed-off-by: David S. Miller <davem@davemloft.net> --- drivers/infiniband/hw/cxgb3/iwch_cm.c | 15 +--------- drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c | 2 +- drivers/net/ethernet/chelsio/cxgb3/l2t.c | 27 ++++++++++++++----- drivers/net/ethernet/chelsio/cxgb3/l2t.h | 2 +- drivers/scsi/cxgbi/cxgb3i/cxgb3i.c | 2 +- 5 files changed, 25 insertions(+), 23 deletions(-)