1 files changed, 59 insertions, 31 deletions

diff --git a/drivers/infiniband/hw/qib/qib_qp.c b/drivers/infiniband/hw/qib/qib_qp.c
index e16751f8639..7e7e16fbee9 100644
--- a/drivers/infiniband/hw/qib/qib_qp.c
+++ b/drivers/infiniband/hw/qib/qib_qp.c
@@ -34,6 +34,7 @@
 
 #include <linux/err.h>
 #include <linux/vmalloc.h>
+#include <linux/jhash.h>
 
 #include "qib.h"
 
@@ -204,6 +205,13 @@ static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
 		clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
 }
 
+static inline unsigned qpn_hash(struct qib_ibdev *dev, u32 qpn)
+{
+	return jhash_1word(qpn, dev->qp_rnd) &
+		(dev->qp_table_size - 1);
+}
+
+
 /*
  * Put the QP into the hash table.
  * The hash table holds a reference to the QP.
@@ -211,22 +219,23 @@ static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
 static void insert_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 {
 	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
-	unsigned n = qp->ibqp.qp_num % dev->qp_table_size;
 	unsigned long flags;
+	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 
 	spin_lock_irqsave(&dev->qpt_lock, flags);
+	atomic_inc(&qp->refcount);
 
 	if (qp->ibqp.qp_num == 0)
-		ibp->qp0 = qp;
+		rcu_assign_pointer(ibp->qp0, qp);
 	else if (qp->ibqp.qp_num == 1)
-		ibp->qp1 = qp;
+		rcu_assign_pointer(ibp->qp1, qp);
 	else {
 		qp->next = dev->qp_table[n];
-		dev->qp_table[n] = qp;
+		rcu_assign_pointer(dev->qp_table[n], qp);
 	}
-	atomic_inc(&qp->refcount);
 
 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	synchronize_rcu();
 }
 
 /*
@@ -236,29 +245,32 @@ static void insert_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 static void remove_qp(struct qib_ibdev *dev, struct qib_qp *qp)
 {
 	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
-	struct qib_qp *q, **qpp;
+	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
 	unsigned long flags;
 
-	qpp = &dev->qp_table[qp->ibqp.qp_num % dev->qp_table_size];
-
 	spin_lock_irqsave(&dev->qpt_lock, flags);
 
 	if (ibp->qp0 == qp) {
-		ibp->qp0 = NULL;
 		atomic_dec(&qp->refcount);
+		rcu_assign_pointer(ibp->qp0, NULL);
 	} else if (ibp->qp1 == qp) {
-		ibp->qp1 = NULL;
 		atomic_dec(&qp->refcount);
-	} else
+		rcu_assign_pointer(ibp->qp1, NULL);
+	} else {
+		struct qib_qp *q, **qpp;
+
+		qpp = &dev->qp_table[n];
 		for (; (q = *qpp) != NULL; qpp = &q->next)
 			if (q == qp) {
-				*qpp = qp->next;
-				qp->next = NULL;
 				atomic_dec(&qp->refcount);
+				rcu_assign_pointer(*qpp, qp->next);
+				qp->next = NULL;
 				break;
 			}
+	}
 
 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	synchronize_rcu();
 }
 
 /**
@@ -280,21 +292,24 @@ unsigned qib_free_all_qps(struct qib_devdata *dd)
 
 		if (!qib_mcast_tree_empty(ibp))
 			qp_inuse++;
-		if (ibp->qp0)
+		rcu_read_lock();
+		if (rcu_dereference(ibp->qp0))
 			qp_inuse++;
-		if (ibp->qp1)
+		if (rcu_dereference(ibp->qp1))
 			qp_inuse++;
+		rcu_read_unlock();
 	}
 
 	spin_lock_irqsave(&dev->qpt_lock, flags);
 	for (n = 0; n < dev->qp_table_size; n++) {
 		qp = dev->qp_table[n];
-		dev->qp_table[n] = NULL;
+		rcu_assign_pointer(dev->qp_table[n], NULL);
 
 		for (; qp; qp = qp->next)
 			qp_inuse++;
 	}
 	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	synchronize_rcu();
 
 	return qp_inuse;
 }
@@ -309,25 +324,28 @@ unsigned qib_free_all_qps(struct qib_devdata *dd)
  */
 struct qib_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
 {
-	struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
-	unsigned long flags;
-	struct qib_qp *qp;
+	struct qib_qp *qp = NULL;
 
-	spin_lock_irqsave(&dev->qpt_lock, flags);
+	if (unlikely(qpn <= 1)) {
+		rcu_read_lock();
+		if (qpn == 0)
+			qp = rcu_dereference(ibp->qp0);
+		else
+			qp = rcu_dereference(ibp->qp1);
+	} else {
+		struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
+		unsigned n = qpn_hash(dev, qpn);
 
-	if (qpn == 0)
-		qp = ibp->qp0;
-	else if (qpn == 1)
-		qp = ibp->qp1;
-	else
-		for (qp = dev->qp_table[qpn % dev->qp_table_size]; qp;
-		     qp = qp->next)
+		rcu_read_lock();
+		for (qp = dev->qp_table[n]; rcu_dereference(qp); qp = qp->next)
 			if (qp->ibqp.qp_num == qpn)
 				break;
+	}
 	if (qp)
-		atomic_inc(&qp->refcount);
+		if (unlikely(!atomic_inc_not_zero(&qp->refcount)))
+			qp = NULL;
 
-	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	rcu_read_unlock();
 	return qp;
 }
 
@@ -765,8 +783,10 @@ int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 		}
 	}
 
-	if (attr_mask & IB_QP_PATH_MTU)
+	if (attr_mask & IB_QP_PATH_MTU) {
 		qp->path_mtu = pmtu;
+		qp->pmtu = ib_mtu_enum_to_int(pmtu);
+	}
 
 	if (attr_mask & IB_QP_RETRY_CNT) {
 		qp->s_retry_cnt = attr->retry_cnt;
@@ -781,8 +801,12 @@ int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
 	if (attr_mask & IB_QP_MIN_RNR_TIMER)
 		qp->r_min_rnr_timer = attr->min_rnr_timer;
 
-	if (attr_mask & IB_QP_TIMEOUT)
+	if (attr_mask & IB_QP_TIMEOUT) {
 		qp->timeout = attr->timeout;
+		qp->timeout_jiffies =
+			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
+				1000UL);
+	}
 
 	if (attr_mask & IB_QP_QKEY)
 		qp->qkey = attr->qkey;
@@ -1013,6 +1037,10 @@ struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
 			ret = ERR_PTR(-ENOMEM);
 			goto bail_swq;
 		}
+		RCU_INIT_POINTER(qp->next, NULL);
+		qp->timeout_jiffies =
+			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
+				1000UL);
 		if (init_attr->srq)
 			sz = 0;
 		else {