2 * Copyright (c) 2006, 2007, 2008, 2009 QLogic Corporation. All rights reserved.
3 * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
5 * This software is available to you under a choice of one of two
6 * licenses. You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
11 * Redistribution and use in source and binary forms, with or
12 * without modification, are permitted provided that the following
15 * - Redistributions of source code must retain the above
16 * copyright notice, this list of conditions and the following
19 * - Redistributions in binary form must reproduce the above
20 * copyright notice, this list of conditions and the following
21 * disclaimer in the documentation and/or other materials
22 * provided with the distribution.
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
34 #include <linux/rculist.h>
39 * qib_mcast_qp_alloc - alloc a struct to link a QP to mcast GID struct
42 static struct qib_mcast_qp *qib_mcast_qp_alloc(struct qib_qp *qp)
44 struct qib_mcast_qp *mqp;
46 mqp = kmalloc(sizeof *mqp, GFP_KERNEL);
51 atomic_inc(&qp->refcount);
57 static void qib_mcast_qp_free(struct qib_mcast_qp *mqp)
59 struct qib_qp *qp = mqp->qp;
61 /* Notify qib_destroy_qp() if it is waiting. */
62 if (atomic_dec_and_test(&qp->refcount))
69 * qib_mcast_alloc - allocate the multicast GID structure
70 * @mgid: the multicast GID
72 * A list of QPs will be attached to this structure.
74 static struct qib_mcast *qib_mcast_alloc(union ib_gid *mgid)
76 struct qib_mcast *mcast;
78 mcast = kmalloc(sizeof *mcast, GFP_KERNEL);
83 INIT_LIST_HEAD(&mcast->qp_list);
84 init_waitqueue_head(&mcast->wait);
85 atomic_set(&mcast->refcount, 0);
86 mcast->n_attached = 0;
92 static void qib_mcast_free(struct qib_mcast *mcast)
94 struct qib_mcast_qp *p, *tmp;
96 list_for_each_entry_safe(p, tmp, &mcast->qp_list, list)
103 * qib_mcast_find - search the global table for the given multicast GID
104 * @ibp: the IB port structure
105 * @mgid: the multicast GID to search for
107 * Returns NULL if not found.
109 * The caller is responsible for decrementing the reference count if found.
111 struct qib_mcast *qib_mcast_find(struct qib_ibport *ibp, union ib_gid *mgid)
115 struct qib_mcast *mcast;
117 spin_lock_irqsave(&ibp->lock, flags);
118 n = ibp->mcast_tree.rb_node;
122 mcast = rb_entry(n, struct qib_mcast, rb_node);
124 ret = memcmp(mgid->raw, mcast->mgid.raw,
125 sizeof(union ib_gid));
131 atomic_inc(&mcast->refcount);
132 spin_unlock_irqrestore(&ibp->lock, flags);
136 spin_unlock_irqrestore(&ibp->lock, flags);
145 * qib_mcast_add - insert mcast GID into table and attach QP struct
146 * @mcast: the mcast GID table
147 * @mqp: the QP to attach
149 * Return zero if both were added. Return EEXIST if the GID was already in
150 * the table but the QP was added. Return ESRCH if the QP was already
151 * attached and neither structure was added.
153 static int qib_mcast_add(struct qib_ibdev *dev, struct qib_ibport *ibp,
154 struct qib_mcast *mcast, struct qib_mcast_qp *mqp)
156 struct rb_node **n = &ibp->mcast_tree.rb_node;
157 struct rb_node *pn = NULL;
160 spin_lock_irq(&ibp->lock);
163 struct qib_mcast *tmcast;
164 struct qib_mcast_qp *p;
167 tmcast = rb_entry(pn, struct qib_mcast, rb_node);
169 ret = memcmp(mcast->mgid.raw, tmcast->mgid.raw,
170 sizeof(union ib_gid));
180 /* Search the QP list to see if this is already there. */
181 list_for_each_entry_rcu(p, &tmcast->qp_list, list) {
182 if (p->qp == mqp->qp) {
187 if (tmcast->n_attached == ib_qib_max_mcast_qp_attached) {
192 tmcast->n_attached++;
194 list_add_tail_rcu(&mqp->list, &tmcast->qp_list);
199 spin_lock(&dev->n_mcast_grps_lock);
200 if (dev->n_mcast_grps_allocated == ib_qib_max_mcast_grps) {
201 spin_unlock(&dev->n_mcast_grps_lock);
206 dev->n_mcast_grps_allocated++;
207 spin_unlock(&dev->n_mcast_grps_lock);
211 list_add_tail_rcu(&mqp->list, &mcast->qp_list);
213 atomic_inc(&mcast->refcount);
214 rb_link_node(&mcast->rb_node, pn, n);
215 rb_insert_color(&mcast->rb_node, &ibp->mcast_tree);
220 spin_unlock_irq(&ibp->lock);
225 int qib_multicast_attach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
227 struct qib_qp *qp = to_iqp(ibqp);
228 struct qib_ibdev *dev = to_idev(ibqp->device);
229 struct qib_ibport *ibp;
230 struct qib_mcast *mcast;
231 struct qib_mcast_qp *mqp;
234 if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
240 * Allocate data structures since its better to do this outside of
241 * spin locks and it will most likely be needed.
243 mcast = qib_mcast_alloc(gid);
248 mqp = qib_mcast_qp_alloc(qp);
250 qib_mcast_free(mcast);
254 ibp = to_iport(ibqp->device, qp->port_num);
255 switch (qib_mcast_add(dev, ibp, mcast, mqp)) {
257 /* Neither was used: OK to attach the same QP twice. */
258 qib_mcast_qp_free(mqp);
259 qib_mcast_free(mcast);
262 case EEXIST: /* The mcast wasn't used */
263 qib_mcast_free(mcast);
267 /* Exceeded the maximum number of mcast groups. */
268 qib_mcast_qp_free(mqp);
269 qib_mcast_free(mcast);
283 int qib_multicast_detach(struct ib_qp *ibqp, union ib_gid *gid, u16 lid)
285 struct qib_qp *qp = to_iqp(ibqp);
286 struct qib_ibdev *dev = to_idev(ibqp->device);
287 struct qib_ibport *ibp = to_iport(ibqp->device, qp->port_num);
288 struct qib_mcast *mcast = NULL;
289 struct qib_mcast_qp *p, *tmp;
294 if (ibqp->qp_num <= 1 || qp->state == IB_QPS_RESET) {
299 spin_lock_irq(&ibp->lock);
301 /* Find the GID in the mcast table. */
302 n = ibp->mcast_tree.rb_node;
305 spin_unlock_irq(&ibp->lock);
310 mcast = rb_entry(n, struct qib_mcast, rb_node);
311 ret = memcmp(gid->raw, mcast->mgid.raw,
312 sizeof(union ib_gid));
321 /* Search the QP list. */
322 list_for_each_entry_safe(p, tmp, &mcast->qp_list, list) {
326 * We found it, so remove it, but don't poison the forward
327 * link until we are sure there are no list walkers.
329 list_del_rcu(&p->list);
332 /* If this was the last attached QP, remove the GID too. */
333 if (list_empty(&mcast->qp_list)) {
334 rb_erase(&mcast->rb_node, &ibp->mcast_tree);
340 spin_unlock_irq(&ibp->lock);
344 * Wait for any list walkers to finish before freeing the
347 wait_event(mcast->wait, atomic_read(&mcast->refcount) <= 1);
348 qib_mcast_qp_free(p);
351 atomic_dec(&mcast->refcount);
352 wait_event(mcast->wait, !atomic_read(&mcast->refcount));
353 qib_mcast_free(mcast);
354 spin_lock_irq(&dev->n_mcast_grps_lock);
355 dev->n_mcast_grps_allocated--;
356 spin_unlock_irq(&dev->n_mcast_grps_lock);
365 int qib_mcast_tree_empty(struct qib_ibport *ibp)
367 return ibp->mcast_tree.rb_node == NULL;