3 * This file is provided under a dual BSD/GPLv2 license. When using or
4 * redistributing this file, you may do so under either license.
8 * Copyright(c) 2015 Intel Corporation.
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of version 2 of the GNU General Public License as
12 * published by the Free Software Foundation.
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
21 * Copyright(c) 2015 Intel Corporation.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
27 * - Redistributions of source code must retain the above copyright
28 * notice, this list of conditions and the following disclaimer.
29 * - Redistributions in binary form must reproduce the above copyright
30 * notice, this list of conditions and the following disclaimer in
31 * the documentation and/or other materials provided with the
33 * - Neither the name of Intel Corporation nor the names of its
34 * contributors may be used to endorse or promote products derived
35 * from this software without specific prior written permission.
37 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
38 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
39 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
40 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
41 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
42 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
43 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
44 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
45 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
46 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
47 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
51 #include <linux/rculist.h>
56 * mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct
59 static struct hfi1_mcast_qp *mcast_qp_alloc(struct hfi1_qp *qp)
61 struct hfi1_mcast_qp *mqp;
63 mqp = kmalloc(sizeof(*mqp), GFP_KERNEL);
68 atomic_inc(&qp->refcount);
74 static void mcast_qp_free(struct hfi1_mcast_qp *mqp)
76 struct hfi1_qp *qp = mqp->qp;
78 /* Notify hfi1_destroy_qp() if it is waiting. */
79 if (atomic_dec_and_test(&qp->refcount))
86 * mcast_alloc - allocate the multicast GID structure
87 * @mgid: the multicast GID
89 * A list of QPs will be attached to this structure.
91 static struct hfi1_mcast *mcast_alloc(union ib_gid *mgid)
93 struct hfi1_mcast *mcast;
95 mcast = kmalloc(sizeof(*mcast), GFP_KERNEL);
100 INIT_LIST_HEAD(&mcast->qp_list);
101 init_waitqueue_head(&mcast->wait);
102 atomic_set(&mcast->refcount, 0);
103 mcast->n_attached = 0;
109 static void mcast_free(struct hfi1_mcast *mcast)
111 struct hfi1_mcast_qp *p, *tmp;
113 list_for_each_entry_safe(p, tmp, &mcast->qp_list, list)
120 * hfi1_mcast_find - search the global table for the given multicast GID
121 * @ibp: the IB port structure
122 * @mgid: the multicast GID to search for
124 * Returns NULL if not found.
126 * The caller is responsible for decrementing the reference count if found.
128 struct hfi1_mcast *hfi1_mcast_find(struct hfi1_ibport *ibp, union ib_gid *mgid)
132 struct hfi1_mcast *mcast;
134 spin_lock_irqsave(&ibp->lock, flags);
135 n = ibp->mcast_tree.rb_node;
139 mcast = rb_entry(n, struct hfi1_mcast, rb_node);
141 ret = memcmp(mgid->raw, mcast->mgid.raw,
142 sizeof(union ib_gid));
148 atomic_inc(&mcast->refcount);
149 spin_unlock_irqrestore(&ibp->lock, flags);
153 spin_unlock_irqrestore(&ibp->lock, flags);
162 * mcast_add - insert mcast GID into table and attach QP struct
163 * @mcast: the mcast GID table
164 * @mqp: the QP to attach
166 * Return zero if both were added. Return EEXIST if the GID was already in
167 * the table but the QP was added. Return ESRCH if the QP was already
168 * attached and neither structure was added.
170 static int mcast_add(struct hfi1_ibdev *dev, struct hfi1_ibport *ibp,
171 struct hfi1_mcast *mcast, struct hfi1_mcast_qp *mqp)
173 struct rb_node **n = &ibp->mcast_tree.rb_node;
174 struct rb_node *pn = NULL;
177 spin_lock_irq(&ibp->lock);
180 struct hfi1_mcast *tmcast;
181 struct hfi1_mcast_qp *p;
184 tmcast = rb_entry(pn, struct hfi1_mcast, rb_node);
186 ret = memcmp(mcast->mgid.raw, tmcast->mgid.raw,
187 sizeof(union ib_gid));
197 /* Search the QP list to see if this is already there. */
198 list_for_each_entry_rcu(p, &tmcast->qp_list, list) {
199 if (p->qp == mqp->qp) {
204 if (tmcast->n_attached == hfi1_max_mcast_qp_attached) {
209 tmcast->n_attached++;
211 list_add_tail_rcu(&mqp->list, &tmcast->qp_list);
216 spin_lock(&dev->n_mcast_grps_lock);
217 if (dev->n_mcast_grps_allocated == hfi1_max_mcast_grps) {
218 spin_unlock(&dev->n_mcast_grps_lock);
223 dev->n_mcast_grps_allocated++;
224 spin_unlock(&dev->n_mcast_grps_lock);
228 list_add_tail_rcu(&mqp->list, &mcast->qp_list);
230 atomic_inc(&mcast->refcount);
231 rb_link_node(&mcast->rb_node, pn, n);
232 rb_insert_color(&mcast->rb_node, &ibp->mcast_tree);
237 spin_unlock_irq(&ibp->lock);
242 int hfi1_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
244 struct hfi1_qp *qp = to_iqp(ibqp);
245 struct hfi1_ibdev *dev = to_idev(ibqp->device);
246 struct hfi1_ibport *ibp;
247 struct hfi1_mcast *mcast;
248 struct hfi1_mcast_qp *mqp;
251 if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
257 * Allocate data structures since its better to do this outside of
258 * spin locks and it will most likely be needed.
260 mcast = mcast_alloc(gid);
265 mqp = mcast_qp_alloc(qp);
271 ibp = to_iport(ibqp->device, qp->port_num);
272 switch (mcast_add(dev, ibp, mcast, mqp)) {
274 /* Neither was used: OK to attach the same QP twice. */
279 case EEXIST: /* The mcast wasn't used */
284 /* Exceeded the maximum number of mcast groups. */
300 int hfi1_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
302 struct hfi1_qp *qp = to_iqp(ibqp);
303 struct hfi1_ibdev *dev = to_idev(ibqp->device);
304 struct hfi1_ibport *ibp = to_iport(ibqp->device, qp->port_num);
305 struct hfi1_mcast *mcast = NULL;
306 struct hfi1_mcast_qp *p, *tmp;
311 if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
316 spin_lock_irq(&ibp->lock);
318 /* Find the GID in the mcast table. */
319 n = ibp->mcast_tree.rb_node;
322 spin_unlock_irq(&ibp->lock);
327 mcast = rb_entry(n, struct hfi1_mcast, rb_node);
328 ret = memcmp(gid->raw, mcast->mgid.raw,
329 sizeof(union ib_gid));
338 /* Search the QP list. */
339 list_for_each_entry_safe(p, tmp, &mcast->qp_list, list) {
343 * We found it, so remove it, but don't poison the forward
344 * link until we are sure there are no list walkers.
346 list_del_rcu(&p->list);
349 /* If this was the last attached QP, remove the GID too. */
350 if (list_empty(&mcast->qp_list)) {
351 rb_erase(&mcast->rb_node, &ibp->mcast_tree);
357 spin_unlock_irq(&ibp->lock);
361 * Wait for any list walkers to finish before freeing the
364 wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1);
368 atomic_dec(&mcast->refcount);
369 wait_event(mcast->wait, !atomic_read(&mcast->refcount));
371 spin_lock_irq(&dev->n_mcast_grps_lock);
372 dev->n_mcast_grps_allocated--;
373 spin_unlock_irq(&dev->n_mcast_grps_lock);
382 int hfi1_mcast_tree_empty(struct hfi1_ibport *ibp)
384 return ibp->mcast_tree.rb_node == NULL;