1/*
2 * Copyright (c) 2012 Mellanox Technologies. All rights reserved.
3 *
4 * This software is available to you under a choice of one of two
5 * licenses.  You may choose to be licensed under the terms of the GNU
6 * General Public License (GPL) Version 2, available from the file
7 * COPYING in the main directory of this source tree, or the
8 * OpenIB.org BSD license below:
9 *
10 *     Redistribution and use in source and binary forms, with or
11 *     without modification, are permitted provided that the following
12 *     conditions are met:
13 *
14 *      - Redistributions of source code must retain the above
15 *        copyright notice, this list of conditions and the following
16 *        disclaimer.
17 *
18 *      - Redistributions in binary form must reproduce the above
19 *        copyright notice, this list of conditions and the following
20 *        disclaimer in the documentation and/or other materials
21 *        provided with the distribution.
22 *
23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 * SOFTWARE.
31 */
32
33#include <rdma/ib_mad.h>
34#include <rdma/ib_smi.h>
35#include <rdma/ib_cache.h>
36#include <rdma/ib_sa.h>
37
38#include <linux/mlx4/cmd.h>
39#include <linux/delay.h>
40
41#include "mlx4_ib.h"
42
43#define MAX_VFS		80
44#define MAX_PEND_REQS_PER_FUNC 4
45#define MAD_TIMEOUT_MS	2000
46
47#define mcg_warn(fmt, arg...)	pr_warn("MCG WARNING: " fmt, ##arg)
48#define mcg_error(fmt, arg...)	pr_err(fmt, ##arg)
49#define mcg_warn_group(group, format, arg...) \
50	pr_warn("%s-%d: %16s (port %d): WARNING: " format, __func__, __LINE__,\
51	(group)->name, group->demux->port, ## arg)
52
53#define mcg_error_group(group, format, arg...) \
54	pr_err("  %16s: " format, (group)->name, ## arg)
55
56static union ib_gid mgid0;
57
58static struct workqueue_struct *clean_wq;
59
60enum mcast_state {
61	MCAST_NOT_MEMBER = 0,
62	MCAST_MEMBER,
63};
64
65enum mcast_group_state {
66	MCAST_IDLE,
67	MCAST_JOIN_SENT,
68	MCAST_LEAVE_SENT,
69	MCAST_RESP_READY
70};
71
72struct mcast_member {
73	enum mcast_state state;
74	uint8_t			join_state;
75	int			num_pend_reqs;
76	struct list_head	pending;
77};
78
79struct ib_sa_mcmember_data {
80	union ib_gid	mgid;
81	union ib_gid	port_gid;
82	__be32		qkey;
83	__be16		mlid;
84	u8		mtusel_mtu;
85	u8		tclass;
86	__be16		pkey;
87	u8		ratesel_rate;
88	u8		lifetmsel_lifetm;
89	__be32		sl_flowlabel_hoplimit;
90	u8		scope_join_state;
91	u8		proxy_join;
92	u8		reserved[2];
93};
94
95struct mcast_group {
96	struct ib_sa_mcmember_data rec;
97	struct rb_node		node;
98	struct list_head	mgid0_list;
99	struct mlx4_ib_demux_ctx *demux;
100	struct mcast_member	func[MAX_VFS];
101	struct mutex		lock;
102	struct work_struct	work;
103	struct list_head	pending_list;
104	int			members[3];
105	enum mcast_group_state	state;
106	enum mcast_group_state	prev_state;
107	struct ib_sa_mad	response_sa_mad;
108	__be64			last_req_tid;
109
110	char			name[33]; /* MGID string */
111	struct device_attribute	dentry;
112
113	/* refcount is the reference count for the following:
114	   1. Each queued request
115	   2. Each invocation of the worker thread
116	   3. Membership of the port at the SA
117	*/
118	atomic_t		refcount;
119
120	/* delayed work to clean pending SM request */
121	struct delayed_work	timeout_work;
122	struct list_head	cleanup_list;
123};
124
125struct mcast_req {
126	int			func;
127	struct ib_sa_mad	sa_mad;
128	struct list_head	group_list;
129	struct list_head	func_list;
130	struct mcast_group	*group;
131	int			clean;
132};
133
134
135#define safe_atomic_dec(ref) \
136        do {\
137                if (atomic_dec_and_test(ref)) \
138			mcg_warn_group(group, "did not expect to reach zero\n"); \
139	} while (0)
140
141static const char *get_state_string(enum mcast_group_state state)
142{
143	switch (state) {
144	case MCAST_IDLE:
145		return "MCAST_IDLE";
146	case MCAST_JOIN_SENT:
147		return "MCAST_JOIN_SENT";
148	case MCAST_LEAVE_SENT:
149		return "MCAST_LEAVE_SENT";
150	case MCAST_RESP_READY:
151		return "MCAST_RESP_READY";
152	}
153	return "Invalid State";
154}
155
156static struct mcast_group *mcast_find(struct mlx4_ib_demux_ctx *ctx,
157				      union ib_gid *mgid)
158{
159	struct rb_node *node = ctx->mcg_table.rb_node;
160	struct mcast_group *group;
161	int ret;
162
163	while (node) {
164		group = rb_entry(node, struct mcast_group, node);
165		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
166		if (!ret)
167			return group;
168
169		if (ret < 0)
170			node = node->rb_left;
171		else
172			node = node->rb_right;
173	}
174	return NULL;
175}
176
177static struct mcast_group *mcast_insert(struct mlx4_ib_demux_ctx *ctx,
178					struct mcast_group *group)
179{
180	struct rb_node **link = &ctx->mcg_table.rb_node;
181	struct rb_node *parent = NULL;
182	struct mcast_group *cur_group;
183	int ret;
184
185	while (*link) {
186		parent = *link;
187		cur_group = rb_entry(parent, struct mcast_group, node);
188
189		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
190			     sizeof group->rec.mgid);
191		if (ret < 0)
192			link = &(*link)->rb_left;
193		else if (ret > 0)
194			link = &(*link)->rb_right;
195		else
196			return cur_group;
197	}
198	rb_link_node(&group->node, parent, link);
199	rb_insert_color(&group->node, &ctx->mcg_table);
200	return NULL;
201}
202
203static int send_mad_to_wire(struct mlx4_ib_demux_ctx *ctx, struct ib_mad *mad)
204{
205	struct mlx4_ib_dev *dev = ctx->dev;
206	struct ib_ah_attr	ah_attr;
207
208	spin_lock(&dev->sm_lock);
209	if (!dev->sm_ah[ctx->port - 1]) {
210		/* port is not yet Active, sm_ah not ready */
211		spin_unlock(&dev->sm_lock);
212		return -EAGAIN;
213	}
214	mlx4_ib_query_ah(dev->sm_ah[ctx->port - 1], &ah_attr);
215	spin_unlock(&dev->sm_lock);
216	return mlx4_ib_send_to_wire(dev, mlx4_master_func_num(dev->dev), ctx->port,
217				    IB_QPT_GSI, 0, 1, IB_QP1_QKEY, &ah_attr, mad);
218}
219
220static int send_mad_to_slave(int slave, struct mlx4_ib_demux_ctx *ctx,
221			     struct ib_mad *mad)
222{
223	struct mlx4_ib_dev *dev = ctx->dev;
224	struct ib_mad_agent *agent = dev->send_agent[ctx->port - 1][1];
225	struct ib_wc wc;
226	struct ib_ah_attr ah_attr;
227
228	/* Our agent might not yet be registered when mads start to arrive */
229	if (!agent)
230		return -EAGAIN;
231
232	ib_query_ah(dev->sm_ah[ctx->port - 1], &ah_attr);
233
234	if (ib_find_cached_pkey(&dev->ib_dev, ctx->port, IB_DEFAULT_PKEY_FULL, &wc.pkey_index))
235		return -EINVAL;
236	wc.sl = 0;
237	wc.dlid_path_bits = 0;
238	wc.port_num = ctx->port;
239	wc.slid = ah_attr.dlid;  /* opensm lid */
240	wc.src_qp = 1;
241	return mlx4_ib_send_to_slave(dev, slave, ctx->port, IB_QPT_GSI, &wc, NULL, mad);
242}
243
244static int send_join_to_wire(struct mcast_group *group, struct ib_sa_mad *sa_mad)
245{
246	struct ib_sa_mad mad;
247	struct ib_sa_mcmember_data *sa_mad_data = (struct ib_sa_mcmember_data *)&mad.data;
248	int ret;
249
250	/* we rely on a mad request as arrived from a VF */
251	memcpy(&mad, sa_mad, sizeof mad);
252
253	/* fix port GID to be the real one (slave 0) */
254	sa_mad_data->port_gid.global.interface_id = group->demux->guid_cache[0];
255
256	/* assign our own TID */
257	mad.mad_hdr.tid = mlx4_ib_get_new_demux_tid(group->demux);
258	group->last_req_tid = mad.mad_hdr.tid; /* keep it for later validation */
259
260	ret = send_mad_to_wire(group->demux, (struct ib_mad *)&mad);
261	/* set timeout handler */
262	if (!ret) {
263		/* calls mlx4_ib_mcg_timeout_handler */
264		queue_delayed_work(group->demux->mcg_wq, &group->timeout_work,
265				msecs_to_jiffies(MAD_TIMEOUT_MS));
266	}
267
268	return ret;
269}
270
271static int send_leave_to_wire(struct mcast_group *group, u8 join_state)
272{
273	struct ib_sa_mad mad;
274	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)&mad.data;
275	int ret;
276
277	memset(&mad, 0, sizeof mad);
278	mad.mad_hdr.base_version = 1;
279	mad.mad_hdr.mgmt_class = IB_MGMT_CLASS_SUBN_ADM;
280	mad.mad_hdr.class_version = 2;
281	mad.mad_hdr.method = IB_SA_METHOD_DELETE;
282	mad.mad_hdr.status = cpu_to_be16(0);
283	mad.mad_hdr.class_specific = cpu_to_be16(0);
284	mad.mad_hdr.tid = mlx4_ib_get_new_demux_tid(group->demux);
285	group->last_req_tid = mad.mad_hdr.tid; /* keep it for later validation */
286	mad.mad_hdr.attr_id = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
287	mad.mad_hdr.attr_mod = cpu_to_be32(0);
288	mad.sa_hdr.sm_key = 0x0;
289	mad.sa_hdr.attr_offset = cpu_to_be16(7);
290	mad.sa_hdr.comp_mask = IB_SA_MCMEMBER_REC_MGID |
291		IB_SA_MCMEMBER_REC_PORT_GID | IB_SA_MCMEMBER_REC_JOIN_STATE;
292
293	*sa_data = group->rec;
294	sa_data->scope_join_state = join_state;
295
296	ret = send_mad_to_wire(group->demux, (struct ib_mad *)&mad);
297	if (ret)
298		group->state = MCAST_IDLE;
299
300	/* set timeout handler */
301	if (!ret) {
302		/* calls mlx4_ib_mcg_timeout_handler */
303		queue_delayed_work(group->demux->mcg_wq, &group->timeout_work,
304				msecs_to_jiffies(MAD_TIMEOUT_MS));
305	}
306
307	return ret;
308}
309
310static int send_reply_to_slave(int slave, struct mcast_group *group,
311		struct ib_sa_mad *req_sa_mad, u16 status)
312{
313	struct ib_sa_mad mad;
314	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)&mad.data;
315	struct ib_sa_mcmember_data *req_sa_data = (struct ib_sa_mcmember_data *)&req_sa_mad->data;
316	int ret;
317
318	memset(&mad, 0, sizeof mad);
319	mad.mad_hdr.base_version = 1;
320	mad.mad_hdr.mgmt_class = IB_MGMT_CLASS_SUBN_ADM;
321	mad.mad_hdr.class_version = 2;
322	mad.mad_hdr.method = IB_MGMT_METHOD_GET_RESP;
323	mad.mad_hdr.status = cpu_to_be16(status);
324	mad.mad_hdr.class_specific = cpu_to_be16(0);
325	mad.mad_hdr.tid = req_sa_mad->mad_hdr.tid;
326	*(u8 *)&mad.mad_hdr.tid = 0; /* resetting tid to 0 */
327	mad.mad_hdr.attr_id = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
328	mad.mad_hdr.attr_mod = cpu_to_be32(0);
329	mad.sa_hdr.sm_key = req_sa_mad->sa_hdr.sm_key;
330	mad.sa_hdr.attr_offset = cpu_to_be16(7);
331	mad.sa_hdr.comp_mask = 0; /* ignored on responses, see IBTA spec */
332
333	*sa_data = group->rec;
334
335	/* reconstruct VF's requested join_state and port_gid */
336	sa_data->scope_join_state &= 0xf0;
337	sa_data->scope_join_state |= (group->func[slave].join_state & 0x0f);
338	memcpy(&sa_data->port_gid, &req_sa_data->port_gid, sizeof req_sa_data->port_gid);
339
340	ret = send_mad_to_slave(slave, group->demux, (struct ib_mad *)&mad);
341	return ret;
342}
343
344static int check_selector(ib_sa_comp_mask comp_mask,
345			  ib_sa_comp_mask selector_mask,
346			  ib_sa_comp_mask value_mask,
347			  u8 src_value, u8 dst_value)
348{
349	int err;
350	u8 selector = dst_value >> 6;
351	dst_value &= 0x3f;
352	src_value &= 0x3f;
353
354	if (!(comp_mask & selector_mask) || !(comp_mask & value_mask))
355		return 0;
356
357	switch (selector) {
358	case IB_SA_GT:
359		err = (src_value <= dst_value);
360		break;
361	case IB_SA_LT:
362		err = (src_value >= dst_value);
363		break;
364	case IB_SA_EQ:
365		err = (src_value != dst_value);
366		break;
367	default:
368		err = 0;
369		break;
370	}
371
372	return err;
373}
374
375static u16 cmp_rec(struct ib_sa_mcmember_data *src,
376		   struct ib_sa_mcmember_data *dst, ib_sa_comp_mask comp_mask)
377{
378	/* src is group record, dst is request record */
379	/* MGID must already match */
380	/* Port_GID we always replace to our Port_GID, so it is a match */
381
382#define MAD_STATUS_REQ_INVALID 0x0200
383	if (comp_mask & IB_SA_MCMEMBER_REC_QKEY && src->qkey != dst->qkey)
384		return MAD_STATUS_REQ_INVALID;
385	if (comp_mask & IB_SA_MCMEMBER_REC_MLID && src->mlid != dst->mlid)
386		return MAD_STATUS_REQ_INVALID;
387	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_MTU_SELECTOR,
388				 IB_SA_MCMEMBER_REC_MTU,
389				 src->mtusel_mtu, dst->mtusel_mtu))
390		return MAD_STATUS_REQ_INVALID;
391	if (comp_mask & IB_SA_MCMEMBER_REC_TRAFFIC_CLASS &&
392	    src->tclass != dst->tclass)
393		return MAD_STATUS_REQ_INVALID;
394	if (comp_mask & IB_SA_MCMEMBER_REC_PKEY && src->pkey != dst->pkey)
395		return MAD_STATUS_REQ_INVALID;
396	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_RATE_SELECTOR,
397				 IB_SA_MCMEMBER_REC_RATE,
398				 src->ratesel_rate, dst->ratesel_rate))
399		return MAD_STATUS_REQ_INVALID;
400	if (check_selector(comp_mask,
401				 IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME_SELECTOR,
402				 IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME,
403				 src->lifetmsel_lifetm, dst->lifetmsel_lifetm))
404		return MAD_STATUS_REQ_INVALID;
405	if (comp_mask & IB_SA_MCMEMBER_REC_SL &&
406			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0xf0000000) !=
407			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0xf0000000))
408		return MAD_STATUS_REQ_INVALID;
409	if (comp_mask & IB_SA_MCMEMBER_REC_FLOW_LABEL &&
410			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0x0fffff00) !=
411			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0x0fffff00))
412		return MAD_STATUS_REQ_INVALID;
413	if (comp_mask & IB_SA_MCMEMBER_REC_HOP_LIMIT &&
414			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0x000000ff) !=
415			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0x000000ff))
416		return MAD_STATUS_REQ_INVALID;
417	if (comp_mask & IB_SA_MCMEMBER_REC_SCOPE &&
418			(src->scope_join_state & 0xf0) !=
419			(dst->scope_join_state & 0xf0))
420		return MAD_STATUS_REQ_INVALID;
421
422	/* join_state checked separately, proxy_join ignored */
423
424	return 0;
425}
426
427/* release group, return 1 if this was last release and group is destroyed
428 * timout work is canceled sync */
429static int release_group(struct mcast_group *group, int from_timeout_handler)
430{
431	struct mlx4_ib_demux_ctx *ctx = group->demux;
432	int nzgroup;
433
434	mutex_lock(&ctx->mcg_table_lock);
435	mutex_lock(&group->lock);
436	if (atomic_dec_and_test(&group->refcount)) {
437		if (!from_timeout_handler) {
438			if (group->state != MCAST_IDLE &&
439			    !cancel_delayed_work(&group->timeout_work)) {
440				atomic_inc(&group->refcount);
441				mutex_unlock(&group->lock);
442				mutex_unlock(&ctx->mcg_table_lock);
443				return 0;
444			}
445		}
446
447		nzgroup = memcmp(&group->rec.mgid, &mgid0, sizeof mgid0);
448		if (nzgroup)
449			del_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
450		if (!list_empty(&group->pending_list))
451			mcg_warn_group(group, "releasing a group with non empty pending list\n");
452		if (nzgroup)
453			rb_erase(&group->node, &ctx->mcg_table);
454		list_del_init(&group->mgid0_list);
455		mutex_unlock(&group->lock);
456		mutex_unlock(&ctx->mcg_table_lock);
457		kfree(group);
458		return 1;
459	} else {
460		mutex_unlock(&group->lock);
461		mutex_unlock(&ctx->mcg_table_lock);
462	}
463	return 0;
464}
465
466static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
467{
468	int i;
469
470	for (i = 0; i < 3; i++, join_state >>= 1)
471		if (join_state & 0x1)
472			group->members[i] += inc;
473}
474
475static u8 get_leave_state(struct mcast_group *group)
476{
477	u8 leave_state = 0;
478	int i;
479
480	for (i = 0; i < 3; i++)
481		if (!group->members[i])
482			leave_state |= (1 << i);
483
484	return leave_state & (group->rec.scope_join_state & 7);
485}
486
487static int join_group(struct mcast_group *group, int slave, u8 join_mask)
488{
489	int ret = 0;
490	u8 join_state;
491
492	/* remove bits that slave is already member of, and adjust */
493	join_state = join_mask & (~group->func[slave].join_state);
494	adjust_membership(group, join_state, 1);
495	group->func[slave].join_state |= join_state;
496	if (group->func[slave].state != MCAST_MEMBER && join_state) {
497		group->func[slave].state = MCAST_MEMBER;
498		ret = 1;
499	}
500	return ret;
501}
502
503static int leave_group(struct mcast_group *group, int slave, u8 leave_state)
504{
505	int ret = 0;
506
507	adjust_membership(group, leave_state, -1);
508	group->func[slave].join_state &= ~leave_state;
509	if (!group->func[slave].join_state) {
510		group->func[slave].state = MCAST_NOT_MEMBER;
511		ret = 1;
512	}
513	return ret;
514}
515
516static int check_leave(struct mcast_group *group, int slave, u8 leave_mask)
517{
518	if (group->func[slave].state != MCAST_MEMBER)
519		return MAD_STATUS_REQ_INVALID;
520
521	/* make sure we're not deleting unset bits */
522	if (~group->func[slave].join_state & leave_mask)
523		return MAD_STATUS_REQ_INVALID;
524
525	if (!leave_mask)
526		return MAD_STATUS_REQ_INVALID;
527
528	return 0;
529}
530
531static void mlx4_ib_mcg_timeout_handler(struct work_struct *work)
532{
533	struct delayed_work *delay = to_delayed_work(work);
534	struct mcast_group *group;
535	struct mcast_req *req = NULL;
536
537	group = container_of(delay, typeof(*group), timeout_work);
538
539	mutex_lock(&group->lock);
540	if (group->state == MCAST_JOIN_SENT) {
541		if (!list_empty(&group->pending_list)) {
542			req = list_first_entry(&group->pending_list, struct mcast_req, group_list);
543			list_del(&req->group_list);
544			list_del(&req->func_list);
545			--group->func[req->func].num_pend_reqs;
546			mutex_unlock(&group->lock);
547			kfree(req);
548			if (memcmp(&group->rec.mgid, &mgid0, sizeof mgid0)) {
549				if (release_group(group, 1))
550					return;
551			} else {
552				kfree(group);
553				return;
554			}
555			mutex_lock(&group->lock);
556		} else
557			mcg_warn_group(group, "DRIVER BUG\n");
558	} else if (group->state == MCAST_LEAVE_SENT) {
559		if (group->rec.scope_join_state & 7)
560			group->rec.scope_join_state &= 0xf8;
561		group->state = MCAST_IDLE;
562		mutex_unlock(&group->lock);
563		if (release_group(group, 1))
564			return;
565		mutex_lock(&group->lock);
566	} else
567		mcg_warn_group(group, "invalid state %s\n", get_state_string(group->state));
568	group->state = MCAST_IDLE;
569	atomic_inc(&group->refcount);
570        queue_work(group->demux->mcg_wq, &group->work);
571        safe_atomic_dec(&group->refcount);
572
573	mutex_unlock(&group->lock);
574}
575
576static int handle_leave_req(struct mcast_group *group, u8 leave_mask,
577			    struct mcast_req *req)
578{
579	u16 status;
580
581	if (req->clean)
582		leave_mask = group->func[req->func].join_state;
583
584	status = check_leave(group, req->func, leave_mask);
585	if (!status)
586		leave_group(group, req->func, leave_mask);
587
588	if (!req->clean)
589		send_reply_to_slave(req->func, group, &req->sa_mad, status);
590	--group->func[req->func].num_pend_reqs;
591	list_del(&req->group_list);
592	list_del(&req->func_list);
593	kfree(req);
594	return 1;
595}
596
597static int handle_join_req(struct mcast_group *group, u8 join_mask,
598			   struct mcast_req *req)
599{
600	u8 group_join_state = group->rec.scope_join_state & 7;
601	int ref = 0;
602	u16 status;
603	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)req->sa_mad.data;
604
605	if (join_mask == (group_join_state & join_mask)) {
606		/* port's membership need not change */
607		status = cmp_rec(&group->rec, sa_data, req->sa_mad.sa_hdr.comp_mask);
608		if (!status)
609			join_group(group, req->func, join_mask);
610
611		--group->func[req->func].num_pend_reqs;
612		send_reply_to_slave(req->func, group, &req->sa_mad, status);
613		list_del(&req->group_list);
614		list_del(&req->func_list);
615		kfree(req);
616		++ref;
617	} else {
618		/* port's membership needs to be updated */
619		group->prev_state = group->state;
620		if (send_join_to_wire(group, &req->sa_mad)) {
621			--group->func[req->func].num_pend_reqs;
622			list_del(&req->group_list);
623			list_del(&req->func_list);
624			kfree(req);
625			ref = 1;
626			group->state = group->prev_state;
627		} else
628			group->state = MCAST_JOIN_SENT;
629	}
630
631	return ref;
632}
633
634static void mlx4_ib_mcg_work_handler(struct work_struct *work)
635{
636	struct mcast_group *group;
637	struct mcast_req *req = NULL;
638	struct ib_sa_mcmember_data *sa_data;
639	u8 req_join_state;
640	int rc = 1; /* release_count - this is for the scheduled work */
641	u16 status;
642	u8 method;
643
644	group = container_of(work, typeof(*group), work);
645
646	mutex_lock(&group->lock);
647
648	/* First, let's see if a response from SM is waiting regarding this group.
649	 * If so, we need to update the group's REC. If this is a bad response, we
650	 * may need to send a bad response to a VF waiting for it. If VF is waiting
651	 * and this is a good response, the VF will be answered later in this func. */
652	if (group->state == MCAST_RESP_READY) {
653		/* cancels mlx4_ib_mcg_timeout_handler */
654		cancel_delayed_work(&group->timeout_work);
655		status = be16_to_cpu(group->response_sa_mad.mad_hdr.status);
656		method = group->response_sa_mad.mad_hdr.method;
657		if (group->last_req_tid != group->response_sa_mad.mad_hdr.tid) {
658			mcg_warn_group(group, "Got MAD response to existing MGID but wrong TID, dropping. Resp TID=%llx, group TID=%llx\n",
659				(long long unsigned int)be64_to_cpu(group->response_sa_mad.mad_hdr.tid),
660				(long long unsigned int)be64_to_cpu(group->last_req_tid));
661			group->state = group->prev_state;
662			goto process_requests;
663		}
664		if (status) {
665			if (!list_empty(&group->pending_list))
666				req = list_first_entry(&group->pending_list,
667						struct mcast_req, group_list);
668			if (method == IB_MGMT_METHOD_GET_RESP) {
669					if (req) {
670						send_reply_to_slave(req->func, group, &req->sa_mad, status);
671						--group->func[req->func].num_pend_reqs;
672						list_del(&req->group_list);
673						list_del(&req->func_list);
674						kfree(req);
675						++rc;
676					} else
677						mcg_warn_group(group, "no request for failed join\n");
678			} else if (method == IB_SA_METHOD_DELETE_RESP && group->demux->flushing)
679				++rc;
680		} else {
681			u8 resp_join_state;
682			u8 cur_join_state;
683
684			resp_join_state = ((struct ib_sa_mcmember_data *)
685						group->response_sa_mad.data)->scope_join_state & 7;
686			cur_join_state = group->rec.scope_join_state & 7;
687
688			if (method == IB_MGMT_METHOD_GET_RESP) {
689				/* successfull join */
690				if (!cur_join_state && resp_join_state)
691					--rc;
692			} else if (!resp_join_state)
693					++rc;
694			memcpy(&group->rec, group->response_sa_mad.data, sizeof group->rec);
695		}
696		group->state = MCAST_IDLE;
697	}
698
699process_requests:
700	/* We should now go over pending join/leave requests, as long as we are idle. */
701	while (!list_empty(&group->pending_list) && group->state == MCAST_IDLE) {
702		req = list_first_entry(&group->pending_list, struct mcast_req,
703				       group_list);
704		sa_data = (struct ib_sa_mcmember_data *)req->sa_mad.data;
705		req_join_state = sa_data->scope_join_state & 0x7;
706
707		/* For a leave request, we will immediately answer the VF, and
708		 * update our internal counters. The actual leave will be sent
709		 * to SM later, if at all needed. We dequeue the request now. */
710		if (req->sa_mad.mad_hdr.method == IB_SA_METHOD_DELETE)
711			rc += handle_leave_req(group, req_join_state, req);
712		else
713			rc += handle_join_req(group, req_join_state, req);
714	}
715
716	/* Handle leaves */
717	if (group->state == MCAST_IDLE) {
718		req_join_state = get_leave_state(group);
719		if (req_join_state) {
720			group->rec.scope_join_state &= ~req_join_state;
721			group->prev_state = group->state;
722			if (send_leave_to_wire(group, req_join_state)) {
723				group->state = group->prev_state;
724				++rc;
725			} else
726				group->state = MCAST_LEAVE_SENT;
727		}
728	}
729
730	if (!list_empty(&group->pending_list) && group->state == MCAST_IDLE)
731		goto process_requests;
732	mutex_unlock(&group->lock);
733
734	while (rc--)
735		release_group(group, 0);
736}
737
738static struct mcast_group *search_relocate_mgid0_group(struct mlx4_ib_demux_ctx *ctx,
739						       __be64 tid,
740						       union ib_gid *new_mgid)
741{
742	struct mcast_group *group = NULL, *cur_group;
743	struct mcast_req *req;
744	struct list_head *pos;
745	struct list_head *n;
746
747	mutex_lock(&ctx->mcg_table_lock);
748	list_for_each_safe(pos, n, &ctx->mcg_mgid0_list) {
749		group = list_entry(pos, struct mcast_group, mgid0_list);
750		mutex_lock(&group->lock);
751		if (group->last_req_tid == tid) {
752			if (memcmp(new_mgid, &mgid0, sizeof mgid0)) {
753				group->rec.mgid = *new_mgid;
754				sprintf(group->name, "%016llx%016llx",
755						(long long unsigned int)be64_to_cpu(group->rec.mgid.global.subnet_prefix),
756						(long long unsigned int)be64_to_cpu(group->rec.mgid.global.interface_id));
757				list_del_init(&group->mgid0_list);
758				cur_group = mcast_insert(ctx, group);
759				if (cur_group) {
760					/* A race between our code and SM. Silently cleaning the new one */
761					req = list_first_entry(&group->pending_list,
762							       struct mcast_req, group_list);
763					--group->func[req->func].num_pend_reqs;
764					list_del(&req->group_list);
765					list_del(&req->func_list);
766					kfree(req);
767					mutex_unlock(&group->lock);
768					mutex_unlock(&ctx->mcg_table_lock);
769					release_group(group, 0);
770					return NULL;
771				}
772
773				atomic_inc(&group->refcount);
774				add_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
775				mutex_unlock(&group->lock);
776				mutex_unlock(&ctx->mcg_table_lock);
777				return group;
778			} else {
779				struct mcast_req *tmp1, *tmp2;
780
781				list_del(&group->mgid0_list);
782				if (!list_empty(&group->pending_list) && group->state != MCAST_IDLE)
783					cancel_delayed_work_sync(&group->timeout_work);
784
785				list_for_each_entry_safe(tmp1, tmp2, &group->pending_list, group_list) {
786					list_del(&tmp1->group_list);
787					kfree(tmp1);
788				}
789				mutex_unlock(&group->lock);
790				mutex_unlock(&ctx->mcg_table_lock);
791				kfree(group);
792				return NULL;
793			}
794		}
795		mutex_unlock(&group->lock);
796	}
797	mutex_unlock(&ctx->mcg_table_lock);
798
799	return NULL;
800}
801
802static ssize_t sysfs_show_group(struct device *dev,
803		struct device_attribute *attr, char *buf);
804
805static struct mcast_group *acquire_group(struct mlx4_ib_demux_ctx *ctx,
806					 union ib_gid *mgid, int create,
807					 gfp_t gfp_mask)
808{
809	struct mcast_group *group, *cur_group;
810	int is_mgid0;
811	int i;
812
813	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
814	if (!is_mgid0) {
815		group = mcast_find(ctx, mgid);
816		if (group)
817			goto found;
818	}
819
820	if (!create)
821		return ERR_PTR(-ENOENT);
822
823	group = kzalloc(sizeof *group, gfp_mask);
824	if (!group)
825		return ERR_PTR(-ENOMEM);
826
827	group->demux = ctx;
828	group->rec.mgid = *mgid;
829	INIT_LIST_HEAD(&group->pending_list);
830	INIT_LIST_HEAD(&group->mgid0_list);
831	for (i = 0; i < MAX_VFS; ++i)
832		INIT_LIST_HEAD(&group->func[i].pending);
833	INIT_WORK(&group->work, mlx4_ib_mcg_work_handler);
834	INIT_DELAYED_WORK(&group->timeout_work, mlx4_ib_mcg_timeout_handler);
835	mutex_init(&group->lock);
836	sprintf(group->name, "%016llx%016llx",
837			(long long unsigned int)be64_to_cpu(group->rec.mgid.global.subnet_prefix),
838			(long long unsigned int)be64_to_cpu(group->rec.mgid.global.interface_id));
839	sysfs_attr_init(&group->dentry.attr);
840	group->dentry.show = sysfs_show_group;
841	group->dentry.store = NULL;
842	group->dentry.attr.name = group->name;
843	group->dentry.attr.mode = 0400;
844	group->state = MCAST_IDLE;
845
846	if (is_mgid0) {
847		list_add(&group->mgid0_list, &ctx->mcg_mgid0_list);
848		goto found;
849	}
850
851	cur_group = mcast_insert(ctx, group);
852	if (cur_group) {
853		mcg_warn("group just showed up %s - confused\n", cur_group->name);
854		kfree(group);
855		return ERR_PTR(-EINVAL);
856	}
857
858	add_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
859
860found:
861	atomic_inc(&group->refcount);
862	return group;
863}
864
865static void queue_req(struct mcast_req *req)
866{
867	struct mcast_group *group = req->group;
868
869	atomic_inc(&group->refcount); /* for the request */
870	atomic_inc(&group->refcount); /* for scheduling the work */
871	list_add_tail(&req->group_list, &group->pending_list);
872	list_add_tail(&req->func_list, &group->func[req->func].pending);
873	/* calls mlx4_ib_mcg_work_handler */
874	queue_work(group->demux->mcg_wq, &group->work);
875        safe_atomic_dec(&group->refcount);
876}
877
878int mlx4_ib_mcg_demux_handler(struct ib_device *ibdev, int port, int slave,
879			      struct ib_sa_mad *mad)
880{
881	struct mlx4_ib_dev *dev = to_mdev(ibdev);
882	struct ib_sa_mcmember_data *rec = (struct ib_sa_mcmember_data *)mad->data;
883	struct mlx4_ib_demux_ctx *ctx = &dev->sriov.demux[port - 1];
884	struct mcast_group *group;
885
886	switch (mad->mad_hdr.method) {
887	case IB_MGMT_METHOD_GET_RESP:
888	case IB_SA_METHOD_DELETE_RESP:
889		mutex_lock(&ctx->mcg_table_lock);
890		group = acquire_group(ctx, &rec->mgid, 0, GFP_KERNEL);
891		mutex_unlock(&ctx->mcg_table_lock);
892		if (IS_ERR(group)) {
893			if (mad->mad_hdr.method == IB_MGMT_METHOD_GET_RESP) {
894				__be64 tid = mad->mad_hdr.tid;
895				*(u8 *)(&tid) = (u8)slave; /* in group we kept the modified TID */
896				group = search_relocate_mgid0_group(ctx, tid, &rec->mgid);
897			} else
898				group = NULL;
899		}
900
901		if (!group)
902			return 1;
903
904		mutex_lock(&group->lock);
905		group->response_sa_mad = *mad;
906		group->prev_state = group->state;
907		group->state = MCAST_RESP_READY;
908		/* calls mlx4_ib_mcg_work_handler */
909		atomic_inc(&group->refcount);
910                queue_work(ctx->mcg_wq, &group->work);
911                safe_atomic_dec(&group->refcount);
912		mutex_unlock(&group->lock);
913		release_group(group, 0);
914		return 1; /* consumed */
915	case IB_MGMT_METHOD_SET:
916	case IB_SA_METHOD_GET_TABLE:
917	case IB_SA_METHOD_GET_TABLE_RESP:
918	case IB_SA_METHOD_DELETE:
919		return 0; /* not consumed, pass-through to guest over tunnel */
920	default:
921		mcg_warn("In demux, port %d: unexpected MCMember method: 0x%x, dropping\n",
922			port, mad->mad_hdr.method);
923		return 1; /* consumed */
924	}
925}
926
927int mlx4_ib_mcg_multiplex_handler(struct ib_device *ibdev, int port,
928				  int slave, struct ib_sa_mad *sa_mad)
929{
930	struct mlx4_ib_dev *dev = to_mdev(ibdev);
931	struct ib_sa_mcmember_data *rec = (struct ib_sa_mcmember_data *)sa_mad->data;
932	struct mlx4_ib_demux_ctx *ctx = &dev->sriov.demux[port - 1];
933	struct mcast_group *group;
934	struct mcast_req *req;
935	int may_create = 0;
936
937	if (ctx->flushing)
938		return -EAGAIN;
939
940	switch (sa_mad->mad_hdr.method) {
941	case IB_MGMT_METHOD_SET:
942		may_create = 1;
943	case IB_SA_METHOD_DELETE:
944		req = kzalloc(sizeof *req, GFP_KERNEL);
945		if (!req)
946			return -ENOMEM;
947
948		req->func = slave;
949		req->sa_mad = *sa_mad;
950
951		mutex_lock(&ctx->mcg_table_lock);
952		group = acquire_group(ctx, &rec->mgid, may_create, GFP_KERNEL);
953		mutex_unlock(&ctx->mcg_table_lock);
954		if (IS_ERR(group)) {
955			kfree(req);
956			return PTR_ERR(group);
957		}
958		mutex_lock(&group->lock);
959		if (group->func[slave].num_pend_reqs > MAX_PEND_REQS_PER_FUNC) {
960			mutex_unlock(&group->lock);
961			mcg_warn_group(group, "Port %d, Func %d has too many pending requests (%d), dropping\n",
962				       port, slave, MAX_PEND_REQS_PER_FUNC);
963			release_group(group, 0);
964			kfree(req);
965			return -ENOMEM;
966		}
967		++group->func[slave].num_pend_reqs;
968		req->group = group;
969		queue_req(req);
970		mutex_unlock(&group->lock);
971		release_group(group, 0);
972		return 1; /* consumed */
973	case IB_SA_METHOD_GET_TABLE:
974	case IB_MGMT_METHOD_GET_RESP:
975	case IB_SA_METHOD_GET_TABLE_RESP:
976	case IB_SA_METHOD_DELETE_RESP:
977		return 0; /* not consumed, pass-through */
978	default:
979		mcg_warn("In multiplex, port %d, func %d: unexpected MCMember method: 0x%x, dropping\n",
980			port, slave, sa_mad->mad_hdr.method);
981		return 1; /* consumed */
982	}
983}
984
985static ssize_t sysfs_show_group(struct device *dev,
986		struct device_attribute *attr, char *buf)
987{
988	struct mcast_group *group =
989		container_of(attr, struct mcast_group, dentry);
990	struct mcast_req *req = NULL;
991	char pending_str[40];
992	char state_str[40];
993	ssize_t len = 0;
994	int f;
995
996	if (group->state == MCAST_IDLE)
997		sprintf(state_str, "%s", get_state_string(group->state));
998	else
999		sprintf(state_str, "%s(TID=0x%llx)",
1000				get_state_string(group->state),
1001				(long long unsigned int)be64_to_cpu(group->last_req_tid));
1002	if (list_empty(&group->pending_list)) {
1003		sprintf(pending_str, "No");
1004	} else {
1005		req = list_first_entry(&group->pending_list, struct mcast_req, group_list);
1006		sprintf(pending_str, "Yes(TID=0x%llx)",
1007				(long long unsigned int)be64_to_cpu(req->sa_mad.mad_hdr.tid));
1008	}
1009	len += sprintf(buf + len, "%1d [%02d,%02d,%02d] %4d %4s %5s     ",
1010			group->rec.scope_join_state & 0xf,
1011			group->members[2], group->members[1], group->members[0],
1012			atomic_read(&group->refcount),
1013			pending_str,
1014			state_str);
1015	for (f = 0; f < MAX_VFS; ++f)
1016		if (group->func[f].state == MCAST_MEMBER)
1017			len += sprintf(buf + len, "%d[%1x] ",
1018					f, group->func[f].join_state);
1019
1020	len += sprintf(buf + len, "\t\t(%4hx %4x %2x %2x %2x %2x %2x "
1021		"%4x %4x %2x %2x)\n",
1022		be16_to_cpu(group->rec.pkey),
1023		be32_to_cpu(group->rec.qkey),
1024		(group->rec.mtusel_mtu & 0xc0) >> 6,
1025		group->rec.mtusel_mtu & 0x3f,
1026		group->rec.tclass,
1027		(group->rec.ratesel_rate & 0xc0) >> 6,
1028		group->rec.ratesel_rate & 0x3f,
1029		(be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0xf0000000) >> 28,
1030		(be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0x0fffff00) >> 8,
1031		be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0x000000ff,
1032		group->rec.proxy_join);
1033
1034	return len;
1035}
1036
1037int mlx4_ib_mcg_port_init(struct mlx4_ib_demux_ctx *ctx)
1038{
1039	char name[20];
1040
1041	atomic_set(&ctx->tid, 0);
1042	sprintf(name, "mlx4_ib_mcg%d", ctx->port);
1043	ctx->mcg_wq = create_singlethread_workqueue(name);
1044	if (!ctx->mcg_wq)
1045		return -ENOMEM;
1046
1047	mutex_init(&ctx->mcg_table_lock);
1048	ctx->mcg_table = RB_ROOT;
1049	INIT_LIST_HEAD(&ctx->mcg_mgid0_list);
1050	ctx->flushing = 0;
1051
1052	return 0;
1053}
1054
1055static void force_clean_group(struct mcast_group *group)
1056{
1057	struct mcast_req *req, *tmp
1058		;
1059	list_for_each_entry_safe(req, tmp, &group->pending_list, group_list) {
1060		list_del(&req->group_list);
1061		kfree(req);
1062	}
1063	del_sysfs_port_mcg_attr(group->demux->dev, group->demux->port, &group->dentry.attr);
1064	rb_erase(&group->node, &group->demux->mcg_table);
1065	kfree(group);
1066}
1067
1068static void _mlx4_ib_mcg_port_cleanup(struct mlx4_ib_demux_ctx *ctx, int destroy_wq)
1069{
1070	int i;
1071	struct rb_node *p;
1072	struct mcast_group *group;
1073	unsigned long end;
1074	int count;
1075
1076	for (i = 0; i < MAX_VFS; ++i)
1077		clean_vf_mcast(ctx, i);
1078
1079	end = jiffies + msecs_to_jiffies(MAD_TIMEOUT_MS + 3000);
1080	do {
1081		count = 0;
1082		mutex_lock(&ctx->mcg_table_lock);
1083		for (p = rb_first(&ctx->mcg_table); p; p = rb_next(p))
1084			++count;
1085		mutex_unlock(&ctx->mcg_table_lock);
1086		if (!count)
1087			break;
1088
1089		msleep(1);
1090	} while (time_after(end, jiffies));
1091
1092	flush_workqueue(ctx->mcg_wq);
1093	if (destroy_wq)
1094		destroy_workqueue(ctx->mcg_wq);
1095
1096	mutex_lock(&ctx->mcg_table_lock);
1097	while ((p = rb_first(&ctx->mcg_table)) != NULL) {
1098		group = rb_entry(p, struct mcast_group, node);
1099		if (atomic_read(&group->refcount))
1100			mcg_warn_group(group, "group refcount %d!!! (pointer %p)\n", atomic_read(&group->refcount), group);
1101
1102		force_clean_group(group);
1103	}
1104	mutex_unlock(&ctx->mcg_table_lock);
1105}
1106
1107struct clean_work {
1108	struct work_struct work;
1109	struct mlx4_ib_demux_ctx *ctx;
1110	int destroy_wq;
1111};
1112
1113static void mcg_clean_task(struct work_struct *work)
1114{
1115	struct clean_work *cw = container_of(work, struct clean_work, work);
1116
1117	_mlx4_ib_mcg_port_cleanup(cw->ctx, cw->destroy_wq);
1118	cw->ctx->flushing = 0;
1119	kfree(cw);
1120}
1121
1122void mlx4_ib_mcg_port_cleanup(struct mlx4_ib_demux_ctx *ctx, int destroy_wq)
1123{
1124	struct clean_work *work;
1125
1126	if (ctx->flushing)
1127		return;
1128
1129	ctx->flushing = 1;
1130
1131	if (destroy_wq) {
1132		_mlx4_ib_mcg_port_cleanup(ctx, destroy_wq);
1133		ctx->flushing = 0;
1134		return;
1135	}
1136
1137	work = kmalloc(sizeof *work, GFP_KERNEL);
1138	if (!work) {
1139		ctx->flushing = 0;
1140		mcg_warn("failed allocating work for cleanup\n");
1141		return;
1142	}
1143
1144	work->ctx = ctx;
1145	work->destroy_wq = destroy_wq;
1146	INIT_WORK(&work->work, mcg_clean_task);
1147	queue_work(clean_wq, &work->work);
1148}
1149
1150static void build_leave_mad(struct mcast_req *req)
1151{
1152	struct ib_sa_mad *mad = &req->sa_mad;
1153
1154	mad->mad_hdr.method = IB_SA_METHOD_DELETE;
1155}
1156
1157
1158static void clear_pending_reqs(struct mcast_group *group, int vf)
1159{
1160	struct mcast_req *req, *tmp, *group_first = NULL;
1161	int clear;
1162	int pend = 0;
1163
1164	if (!list_empty(&group->pending_list))
1165		group_first = list_first_entry(&group->pending_list, struct mcast_req, group_list);
1166
1167	list_for_each_entry_safe(req, tmp, &group->func[vf].pending, func_list) {
1168		clear = 1;
1169		if (group_first == req &&
1170		    (group->state == MCAST_JOIN_SENT ||
1171		     group->state == MCAST_LEAVE_SENT)) {
1172			clear = cancel_delayed_work(&group->timeout_work);
1173			pend = !clear;
1174			group->state = MCAST_IDLE;
1175		}
1176		if (clear) {
1177			--group->func[vf].num_pend_reqs;
1178			list_del(&req->group_list);
1179			list_del(&req->func_list);
1180			kfree(req);
1181			atomic_dec(&group->refcount);
1182		}
1183	}
1184
1185	if (!pend && (!list_empty(&group->func[vf].pending) || group->func[vf].num_pend_reqs)) {
1186		mcg_warn_group(group, "DRIVER BUG: list_empty %d, num_pend_reqs %d\n",
1187			       list_empty(&group->func[vf].pending), group->func[vf].num_pend_reqs);
1188	}
1189}
1190
1191static int push_deleteing_req(struct mcast_group *group, int slave)
1192{
1193	struct mcast_req *req;
1194	struct mcast_req *pend_req;
1195
1196	if (!group->func[slave].join_state)
1197		return 0;
1198
1199	req = kzalloc(sizeof *req, GFP_KERNEL);
1200	if (!req) {
1201		mcg_warn_group(group, "failed allocation - may leave stall groups\n");
1202		return -ENOMEM;
1203	}
1204
1205	if (!list_empty(&group->func[slave].pending)) {
1206		pend_req = list_entry(group->func[slave].pending.prev, struct mcast_req, group_list);
1207		if (pend_req->clean) {
1208			kfree(req);
1209			return 0;
1210		}
1211	}
1212
1213	req->clean = 1;
1214	req->func = slave;
1215	req->group = group;
1216	++group->func[slave].num_pend_reqs;
1217	build_leave_mad(req);
1218	queue_req(req);
1219	return 0;
1220}
1221
1222void clean_vf_mcast(struct mlx4_ib_demux_ctx *ctx, int slave)
1223{
1224	struct mcast_group *group;
1225	struct rb_node *p;
1226
1227	mutex_lock(&ctx->mcg_table_lock);
1228	for (p = rb_first(&ctx->mcg_table); p; p = rb_next(p)) {
1229		group = rb_entry(p, struct mcast_group, node);
1230		mutex_lock(&group->lock);
1231		if (atomic_read(&group->refcount)) {
1232			/* clear pending requests of this VF */
1233			clear_pending_reqs(group, slave);
1234			push_deleteing_req(group, slave);
1235		}
1236		mutex_unlock(&group->lock);
1237	}
1238	mutex_unlock(&ctx->mcg_table_lock);
1239}
1240
1241
1242int mlx4_ib_mcg_init(void)
1243{
1244	clean_wq = create_singlethread_workqueue("mlx4_ib_mcg");
1245	if (!clean_wq)
1246		return -ENOMEM;
1247
1248	return 0;
1249}
1250
1251void mlx4_ib_mcg_destroy(void)
1252{
1253	destroy_workqueue(clean_wq);
1254}
1255