Cleanup rxe_mcast.c code by separating initialization and cleanup
of mca objects into subroutines. Added remaining documentation
comments.
Signed-off-by: Bob Pearson <rpearsonhpe@xxxxxxxxx>
---
drivers/infiniband/sw/rxe/rxe_mcast.c | 162 +++++++++++++++++++-------
drivers/infiniband/sw/rxe/rxe_verbs.h | 1 +
2 files changed, 121 insertions(+), 42 deletions(-)
diff --git a/drivers/infiniband/sw/rxe/rxe_mcast.c b/drivers/infiniband/sw/rxe/rxe_mcast.c
index 77f166a5d5c8..865e6e85084f 100644
--- a/drivers/infiniband/sw/rxe/rxe_mcast.c
+++ b/drivers/infiniband/sw/rxe/rxe_mcast.c
@@ -178,7 +178,7 @@ static int rxe_get_mcg(struct rxe_dev *rxe, union ib_gid *mgid,
struct rxe_mcg **mcgp)
{
struct rxe_mcg *mcg, *tmp;
- int ret;
+ int err;
if (rxe->attr.max_mcast_grp == 0)
return -EINVAL;
@@ -206,12 +206,12 @@ static int rxe_get_mcg(struct rxe_dev *rxe, union ib_gid *mgid,
}
if (atomic_inc_return(&rxe->mcg_num) > rxe->attr.max_mcast_grp) {
- ret = -ENOMEM;
+ err = -ENOMEM;
goto err_dec;
}
- ret = rxe_mcast_add(rxe, mgid);
- if (ret)
+ err = rxe_mcast_add(rxe, mgid);
+ if (err)
goto err_dec;
kref_init(&mcg->ref_cnt);
@@ -230,7 +230,7 @@ static int rxe_get_mcg(struct rxe_dev *rxe, union ib_gid *mgid,
atomic_dec(&rxe->mcg_num);
spin_unlock_bh(&rxe->mcg_lock);
kfree(mcg);
- return ret;
+ return err;
}
/**
@@ -269,11 +269,59 @@ void rxe_cleanup_mcg(struct kref *kref)
spin_unlock_bh(&rxe->mcg_lock);
}
-static int rxe_mcast_add_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
- struct rxe_mcg *mcg)
+/**
+ * __rxe_init_mca - initialize a new mca holding lock
+ * @qp: qp object
+ * @mcg: mcg object
+ * @mca: empty space for new mca
+ *
+ * Context: caller must hold references on qp and mcg, rxe->mcg_lock
+ * and pass memory for new mca
+ *
+ * Returns: 0 on success else an error
+ */
+static int __rxe_init_mca(struct rxe_qp *qp, struct rxe_mcg *mcg,
+ struct rxe_mca *mca)
{
- int err;
+ struct rxe_dev *rxe = to_rdev(qp->ibqp.device);
+ int n;
+
+ n = atomic_inc_return(&rxe->mcg_attach);
+ if (n > rxe->attr.max_total_mcast_qp_attach) {
+ atomic_dec(&rxe->mcg_attach);
+ return -ENOMEM;
+ }
+
+ n = atomic_inc_return(&mcg->qp_num);
+ if (n > rxe->attr.max_mcast_qp_attach) {
+ atomic_dec(&mcg->qp_num);
+ atomic_dec(&rxe->mcg_attach);
+ return -ENOMEM;
+ }
+
+ atomic_inc(&qp->mcg_num);
+
+ rxe_add_ref(qp);
+ mca->qp = qp;
+
+ list_add_tail(&mca->qp_list, &mcg->qp_list);
+
+ return 0;
+}
+
+/**
+ * rxe_attach_mcg - attach qp to mcg if not already attached
+ * @mcg: mcg object
+ * @qp: qp object
+ *
+ * Context: caller must hold reference on qp and mcg.
+ * Returns: 0 on success else an error
+ */
+static int rxe_attach_mcg(struct rxe_mcg *mcg, struct rxe_qp *qp)
+{
+ struct rxe_dev *rxe = mcg->rxe;
struct rxe_mca *mca, *new_mca;
+ int err;
/* check to see if the qp is already a member of the group */
spin_lock_bh(&rxe->mcg_lock);
@@ -296,61 +344,74 @@ static int rxe_mcast_add_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
if (mca->qp == qp) {
kfree(new_mca);
err = 0;
- goto out;
+ goto done;
}
}
- if (atomic_read(&mcg->qp_num) >= rxe->attr.max_mcast_qp_attach) {
- err = -ENOMEM;
- goto out;
- }
+ mca = new_mca;
+ err = __rxe_init_mca(qp, mcg, mca);
+ if (err)
+ kfree(mca);
+done:
+ spin_unlock_bh(&rxe->mcg_lock);
- atomic_inc(&mcg->qp_num);
- new_mca->qp = qp;
- atomic_inc(&qp->mcg_num);
+ return err;
+}
+
+/**
+ * __rxe_cleanup_mca - cleanup mca object holding lock
+ * @mca: mca object
+ * @mcg: mcg object
+ *
+ * Context: caller must hold a reference to mcg and rxe->mcg_lock
+ */
+static void __rxe_cleanup_mca(struct rxe_mca *mca, struct rxe_mcg *mcg)
+{
+ list_del(&mca->qp_list);
- list_add_tail(&new_mca->qp_list, &mcg->qp_list);
+ atomic_dec(&mcg->qp_num);
+ atomic_dec(&mcg->rxe->mcg_attach);
+ atomic_dec(&mca->qp->mcg_num);
- err = 0;
-out:
- spin_unlock_bh(&rxe->mcg_lock);
- return err;
+ rxe_drop_ref(mca->qp);
}
-static int rxe_mcast_drop_grp_elem(struct rxe_dev *rxe, struct rxe_qp *qp,
- union ib_gid *mgid)
+/**
+ * rxe_detach_mcg - detach qp from mcg
+ * @mcg: mcg object
+ * @qp: qp object
+ *
+ * Returns: 0 on success else an error if qp is not attached.
+ */
+static int rxe_detach_mcg(struct rxe_mcg *mcg, struct rxe_qp *qp)
{
- struct rxe_mcg *mcg;
+ struct rxe_dev *rxe = mcg->rxe;
struct rxe_mca *mca, *tmp;
- int n;
-
- mcg = rxe_lookup_mcg(rxe, mgid);
- if (!mcg)
- goto err1;
spin_lock_bh(&rxe->mcg_lock);
-
list_for_each_entry_safe(mca, tmp, &mcg->qp_list, qp_list) {
if (mca->qp == qp) {
- list_del(&mca->qp_list);
- n = atomic_dec_return(&mcg->qp_num);
- if (n <= 0)
+ __rxe_cleanup_mca(mca, mcg);
+ if (atomic_read(&mcg->qp_num) <= 0)
kref_put(&mcg->ref_cnt, __rxe_cleanup_mcg);
- atomic_dec(&qp->mcg_num);
-
spin_unlock_bh(&rxe->mcg_lock);
- kref_put(&mcg->ref_cnt, __rxe_cleanup_mcg);
kfree(mca);
return 0;
}
}
-
spin_unlock_bh(&rxe->mcg_lock);
- kref_put(&mcg->ref_cnt, rxe_cleanup_mcg);
-err1:
+
return -EINVAL;
}
+/**
+ * rxe_attach_mcast - attach qp to multicast group (see IBA-11.3.1)
+ * @ibqp: (IB) qp object
+ * @mgid: multicast IP address
+ * @mlid: multicast LID, ignored for RoCEv2 (see IBA-A17.5.6)
+ *
+ * Returns: 0 on success else an errno
+ */
int rxe_attach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid)
{
int err;
@@ -363,18 +424,35 @@ int rxe_attach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid)
if (err)
return err;
- err = rxe_mcast_add_grp_elem(rxe, qp, mcg);
-
+ err = rxe_attach_mcg(mcg, qp);
kref_put(&mcg->ref_cnt, rxe_cleanup_mcg);
+
return err;
}
+/**
+ * rxe_detach_mcast - detach qp from multicast group (see IBA-11.3.2)
+ * @ibqp: address of (IB) qp object
+ * @mgid: multicast IP address
+ * @mlid: multicast LID, ignored for RoCEv2 (see IBA-A17.5.6)
+ *
+ * Returns: 0 on success else an errno
+ */
int rxe_detach_mcast(struct ib_qp *ibqp, union ib_gid *mgid, u16 mlid)
{
struct rxe_dev *rxe = to_rdev(ibqp->device);
struct rxe_qp *qp = to_rqp(ibqp);
+ struct rxe_mcg *mcg;
+ int err;
+
+ mcg = rxe_lookup_mcg(rxe, mgid);
+ if (!mcg)
+ return -EINVAL;
- return rxe_mcast_drop_grp_elem(rxe, qp, mgid);
+ err = rxe_detach_mcg(mcg, qp);
+ kref_put(&mcg->ref_cnt, rxe_cleanup_mcg);
+
+ return err;
}
/**
diff --git a/drivers/infiniband/sw/rxe/rxe_verbs.h b/drivers/infiniband/sw/rxe/rxe_verbs.h
index dea24ebdb3d0..76350d43ce2a 100644
--- a/drivers/infiniband/sw/rxe/rxe_verbs.h
+++ b/drivers/infiniband/sw/rxe/rxe_verbs.h
@@ -400,6 +400,7 @@ struct rxe_dev {
spinlock_t mcg_lock; /* guard multicast groups */
struct rb_root mcg_tree;
atomic_t mcg_num;
+ atomic_t mcg_attach;
spinlock_t pending_lock; /* guard pending_mmaps */
struct list_head pending_mmaps;
--
2.32.0
