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Diffstat (limited to 'drivers/infiniband/sw/rdmavt/mcast.c')
-rw-r--r--drivers/infiniband/sw/rdmavt/mcast.c401
1 files changed, 401 insertions, 0 deletions
diff --git a/drivers/infiniband/sw/rdmavt/mcast.c b/drivers/infiniband/sw/rdmavt/mcast.c
new file mode 100644
index 000000000..a123874e1
--- /dev/null
+++ b/drivers/infiniband/sw/rdmavt/mcast.c
@@ -0,0 +1,401 @@
+// SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
+/*
+ * Copyright(c) 2016 Intel Corporation.
+ */
+
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/rculist.h>
+#include <rdma/rdma_vt.h>
+#include <rdma/rdmavt_qp.h>
+
+#include "mcast.h"
+
+/**
+ * rvt_driver_mcast_init - init resources for multicast
+ * @rdi: rvt dev struct
+ *
+ * This is per device that registers with rdmavt
+ */
+void rvt_driver_mcast_init(struct rvt_dev_info *rdi)
+{
+ /*
+ * Anything that needs setup for multicast on a per driver or per rdi
+ * basis should be done in here.
+ */
+ spin_lock_init(&rdi->n_mcast_grps_lock);
+}
+
+/**
+ * rvt_mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct
+ * @qp: the QP to link
+ */
+static struct rvt_mcast_qp *rvt_mcast_qp_alloc(struct rvt_qp *qp)
+{
+ struct rvt_mcast_qp *mqp;
+
+ mqp = kmalloc(sizeof(*mqp), GFP_KERNEL);
+ if (!mqp)
+ goto bail;
+
+ mqp->qp = qp;
+ rvt_get_qp(qp);
+
+bail:
+ return mqp;
+}
+
+static void rvt_mcast_qp_free(struct rvt_mcast_qp *mqp)
+{
+ struct rvt_qp *qp = mqp->qp;
+
+ /* Notify hfi1_destroy_qp() if it is waiting. */
+ rvt_put_qp(qp);
+
+ kfree(mqp);
+}
+
+/**
+ * rvt_mcast_alloc - allocate the multicast GID structure
+ * @mgid: the multicast GID
+ * @lid: the muilticast LID (host order)
+ *
+ * A list of QPs will be attached to this structure.
+ */
+static struct rvt_mcast *rvt_mcast_alloc(union ib_gid *mgid, u16 lid)
+{
+ struct rvt_mcast *mcast;
+
+ mcast = kzalloc(sizeof(*mcast), GFP_KERNEL);
+ if (!mcast)
+ goto bail;
+
+ mcast->mcast_addr.mgid = *mgid;
+ mcast->mcast_addr.lid = lid;
+
+ INIT_LIST_HEAD(&mcast->qp_list);
+ init_waitqueue_head(&mcast->wait);
+ atomic_set(&mcast->refcount, 0);
+
+bail:
+ return mcast;
+}
+
+static void rvt_mcast_free(struct rvt_mcast *mcast)
+{
+ struct rvt_mcast_qp *p, *tmp;
+
+ list_for_each_entry_safe(p, tmp, &mcast->qp_list, list)
+ rvt_mcast_qp_free(p);
+
+ kfree(mcast);
+}
+
+/**
+ * rvt_mcast_find - search the global table for the given multicast GID/LID
+ * NOTE: It is valid to have 1 MLID with multiple MGIDs. It is not valid
+ * to have 1 MGID with multiple MLIDs.
+ * @ibp: the IB port structure
+ * @mgid: the multicast GID to search for
+ * @lid: the multicast LID portion of the multicast address (host order)
+ *
+ * The caller is responsible for decrementing the reference count if found.
+ *
+ * Return: NULL if not found.
+ */
+struct rvt_mcast *rvt_mcast_find(struct rvt_ibport *ibp, union ib_gid *mgid,
+ u16 lid)
+{
+ struct rb_node *n;
+ unsigned long flags;
+ struct rvt_mcast *found = NULL;
+
+ spin_lock_irqsave(&ibp->lock, flags);
+ n = ibp->mcast_tree.rb_node;
+ while (n) {
+ int ret;
+ struct rvt_mcast *mcast;
+
+ mcast = rb_entry(n, struct rvt_mcast, rb_node);
+
+ ret = memcmp(mgid->raw, mcast->mcast_addr.mgid.raw,
+ sizeof(*mgid));
+ if (ret < 0) {
+ n = n->rb_left;
+ } else if (ret > 0) {
+ n = n->rb_right;
+ } else {
+ /* MGID/MLID must match */
+ if (mcast->mcast_addr.lid == lid) {
+ atomic_inc(&mcast->refcount);
+ found = mcast;
+ }
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&ibp->lock, flags);
+ return found;
+}
+EXPORT_SYMBOL(rvt_mcast_find);
+
+/*
+ * rvt_mcast_add - insert mcast GID into table and attach QP struct
+ * @mcast: the mcast GID table
+ * @mqp: the QP to attach
+ *
+ * Return: zero if both were added. Return EEXIST if the GID was already in
+ * the table but the QP was added. Return ESRCH if the QP was already
+ * attached and neither structure was added. Return EINVAL if the MGID was
+ * found, but the MLID did NOT match.
+ */
+static int rvt_mcast_add(struct rvt_dev_info *rdi, struct rvt_ibport *ibp,
+ struct rvt_mcast *mcast, struct rvt_mcast_qp *mqp)
+{
+ struct rb_node **n = &ibp->mcast_tree.rb_node;
+ struct rb_node *pn = NULL;
+ int ret;
+
+ spin_lock_irq(&ibp->lock);
+
+ while (*n) {
+ struct rvt_mcast *tmcast;
+ struct rvt_mcast_qp *p;
+
+ pn = *n;
+ tmcast = rb_entry(pn, struct rvt_mcast, rb_node);
+
+ ret = memcmp(mcast->mcast_addr.mgid.raw,
+ tmcast->mcast_addr.mgid.raw,
+ sizeof(mcast->mcast_addr.mgid));
+ if (ret < 0) {
+ n = &pn->rb_left;
+ continue;
+ }
+ if (ret > 0) {
+ n = &pn->rb_right;
+ continue;
+ }
+
+ if (tmcast->mcast_addr.lid != mcast->mcast_addr.lid) {
+ ret = EINVAL;
+ goto bail;
+ }
+
+ /* Search the QP list to see if this is already there. */
+ list_for_each_entry_rcu(p, &tmcast->qp_list, list) {
+ if (p->qp == mqp->qp) {
+ ret = ESRCH;
+ goto bail;
+ }
+ }
+ if (tmcast->n_attached ==
+ rdi->dparms.props.max_mcast_qp_attach) {
+ ret = ENOMEM;
+ goto bail;
+ }
+
+ tmcast->n_attached++;
+
+ list_add_tail_rcu(&mqp->list, &tmcast->qp_list);
+ ret = EEXIST;
+ goto bail;
+ }
+
+ spin_lock(&rdi->n_mcast_grps_lock);
+ if (rdi->n_mcast_grps_allocated == rdi->dparms.props.max_mcast_grp) {
+ spin_unlock(&rdi->n_mcast_grps_lock);
+ ret = ENOMEM;
+ goto bail;
+ }
+
+ rdi->n_mcast_grps_allocated++;
+ spin_unlock(&rdi->n_mcast_grps_lock);
+
+ mcast->n_attached++;
+
+ list_add_tail_rcu(&mqp->list, &mcast->qp_list);
+
+ atomic_inc(&mcast->refcount);
+ rb_link_node(&mcast->rb_node, pn, n);
+ rb_insert_color(&mcast->rb_node, &ibp->mcast_tree);
+
+ ret = 0;
+
+bail:
+ spin_unlock_irq(&ibp->lock);
+
+ return ret;
+}
+
+/**
+ * rvt_attach_mcast - attach a qp to a multicast group
+ * @ibqp: Infiniband qp
+ * @gid: multicast guid
+ * @lid: multicast lid
+ *
+ * Return: 0 on success
+ */
+int rvt_attach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
+{
+ struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
+ struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device);
+ struct rvt_ibport *ibp = rdi->ports[qp->port_num - 1];
+ struct rvt_mcast *mcast;
+ struct rvt_mcast_qp *mqp;
+ int ret = -ENOMEM;
+
+ if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET)
+ return -EINVAL;
+
+ /*
+ * Allocate data structures since its better to do this outside of
+ * spin locks and it will most likely be needed.
+ */
+ mcast = rvt_mcast_alloc(gid, lid);
+ if (!mcast)
+ return -ENOMEM;
+
+ mqp = rvt_mcast_qp_alloc(qp);
+ if (!mqp)
+ goto bail_mcast;
+
+ switch (rvt_mcast_add(rdi, ibp, mcast, mqp)) {
+ case ESRCH:
+ /* Neither was used: OK to attach the same QP twice. */
+ ret = 0;
+ goto bail_mqp;
+ case EEXIST: /* The mcast wasn't used */
+ ret = 0;
+ goto bail_mcast;
+ case ENOMEM:
+ /* Exceeded the maximum number of mcast groups. */
+ ret = -ENOMEM;
+ goto bail_mqp;
+ case EINVAL:
+ /* Invalid MGID/MLID pair */
+ ret = -EINVAL;
+ goto bail_mqp;
+ default:
+ break;
+ }
+
+ return 0;
+
+bail_mqp:
+ rvt_mcast_qp_free(mqp);
+
+bail_mcast:
+ rvt_mcast_free(mcast);
+
+ return ret;
+}
+
+/**
+ * rvt_detach_mcast - remove a qp from a multicast group
+ * @ibqp: Infiniband qp
+ * @gid: multicast guid
+ * @lid: multicast lid
+ *
+ * Return: 0 on success
+ */
+int rvt_detach_mcast(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
+{
+ struct rvt_qp *qp = ibqp_to_rvtqp(ibqp);
+ struct rvt_dev_info *rdi = ib_to_rvt(ibqp->device);
+ struct rvt_ibport *ibp = rdi->ports[qp->port_num - 1];
+ struct rvt_mcast *mcast = NULL;
+ struct rvt_mcast_qp *p, *tmp, *delp = NULL;
+ struct rb_node *n;
+ int last = 0;
+ int ret = 0;
+
+ if (ibqp->qp_num <= 1)
+ return -EINVAL;
+
+ spin_lock_irq(&ibp->lock);
+
+ /* Find the GID in the mcast table. */
+ n = ibp->mcast_tree.rb_node;
+ while (1) {
+ if (!n) {
+ spin_unlock_irq(&ibp->lock);
+ return -EINVAL;
+ }
+
+ mcast = rb_entry(n, struct rvt_mcast, rb_node);
+ ret = memcmp(gid->raw, mcast->mcast_addr.mgid.raw,
+ sizeof(*gid));
+ if (ret < 0) {
+ n = n->rb_left;
+ } else if (ret > 0) {
+ n = n->rb_right;
+ } else {
+ /* MGID/MLID must match */
+ if (mcast->mcast_addr.lid != lid) {
+ spin_unlock_irq(&ibp->lock);
+ return -EINVAL;
+ }
+ break;
+ }
+ }
+
+ /* Search the QP list. */
+ list_for_each_entry_safe(p, tmp, &mcast->qp_list, list) {
+ if (p->qp != qp)
+ continue;
+ /*
+ * We found it, so remove it, but don't poison the forward
+ * link until we are sure there are no list walkers.
+ */
+ list_del_rcu(&p->list);
+ mcast->n_attached--;
+ delp = p;
+
+ /* If this was the last attached QP, remove the GID too. */
+ if (list_empty(&mcast->qp_list)) {
+ rb_erase(&mcast->rb_node, &ibp->mcast_tree);
+ last = 1;
+ }
+ break;
+ }
+
+ spin_unlock_irq(&ibp->lock);
+ /* QP not attached */
+ if (!delp)
+ return -EINVAL;
+
+ /*
+ * Wait for any list walkers to finish before freeing the
+ * list element.
+ */
+ wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1);
+ rvt_mcast_qp_free(delp);
+
+ if (last) {
+ atomic_dec(&mcast->refcount);
+ wait_event(mcast->wait, !atomic_read(&mcast->refcount));
+ rvt_mcast_free(mcast);
+ spin_lock_irq(&rdi->n_mcast_grps_lock);
+ rdi->n_mcast_grps_allocated--;
+ spin_unlock_irq(&rdi->n_mcast_grps_lock);
+ }
+
+ return 0;
+}
+
+/**
+ * rvt_mcast_tree_empty - determine if any qps are attached to any mcast group
+ * @rdi: rvt dev struct
+ *
+ * Return: in use count
+ */
+int rvt_mcast_tree_empty(struct rvt_dev_info *rdi)
+{
+ int i;
+ int in_use = 0;
+
+ for (i = 0; i < rdi->dparms.nports; i++)
+ if (rdi->ports[i]->mcast_tree.rb_node)
+ in_use++;
+ return in_use;
+}