From a4757123aeadf450b5b3c5f51f214660e20477f3 Mon Sep 17 00:00:00 2001 From: David Miller Date: Fri, 2 Dec 2011 16:52:18 +0000 Subject: [PATCH] cxgb3: Rework t3_l2t_get to take a dst_entry instead of a neighbour. 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 --- drivers/infiniband/hw/cxgb3/iwch_cm.c | 15 ++--------- .../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(-) diff --git a/drivers/infiniband/hw/cxgb3/iwch_cm.c b/drivers/infiniband/hw/cxgb3/iwch_cm.c index 23686df0517c..740dcc065cf2 100644 --- a/drivers/infiniband/hw/cxgb3/iwch_cm.c +++ b/drivers/infiniband/hw/cxgb3/iwch_cm.c @@ -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; diff --git a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c index 6ed9f87db8ea..596cfe32d79e 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c +++ b/drivers/net/ethernet/chelsio/cxgb3/cxgb3_offload.c @@ -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__); diff --git a/drivers/net/ethernet/chelsio/cxgb3/l2t.c b/drivers/net/ethernet/chelsio/cxgb3/l2t.c index 70fec8b1140f..3fa3c8833ed7 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/l2t.c +++ b/drivers/net/ethernet/chelsio/cxgb3/l2t.c @@ -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(); diff --git a/drivers/net/ethernet/chelsio/cxgb3/l2t.h b/drivers/net/ethernet/chelsio/cxgb3/l2t.h index c5f54796e2cb..c4e864369751 100644 --- a/drivers/net/ethernet/chelsio/cxgb3/l2t.h +++ b/drivers/net/ethernet/chelsio/cxgb3/l2t.h @@ -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); diff --git a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c index 88902d380f88..36739da8bc15 100644 --- a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c +++ b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c @@ -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;