xref: /openbmc/linux/drivers/infiniband/hw/mlx4/mcg.c (revision 206204a1)
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/rbtree.h>
40 #include <linux/delay.h>
41 
42 #include "mlx4_ib.h"
43 
44 #define MAX_VFS		80
45 #define MAX_PEND_REQS_PER_FUNC 4
46 #define MAD_TIMEOUT_MS	2000
47 
48 #define mcg_warn(fmt, arg...)	pr_warn("MCG WARNING: " fmt, ##arg)
49 #define mcg_error(fmt, arg...)	pr_err(fmt, ##arg)
50 #define mcg_warn_group(group, format, arg...) \
51 	pr_warn("%s-%d: %16s (port %d): WARNING: " format, __func__, __LINE__,\
52 	(group)->name, group->demux->port, ## arg)
53 
54 #define mcg_error_group(group, format, arg...) \
55 	pr_err("  %16s: " format, (group)->name, ## arg)
56 
57 
58 static union ib_gid mgid0;
59 
60 static struct workqueue_struct *clean_wq;
61 
62 enum mcast_state {
63 	MCAST_NOT_MEMBER = 0,
64 	MCAST_MEMBER,
65 };
66 
67 enum mcast_group_state {
68 	MCAST_IDLE,
69 	MCAST_JOIN_SENT,
70 	MCAST_LEAVE_SENT,
71 	MCAST_RESP_READY
72 };
73 
74 struct mcast_member {
75 	enum mcast_state state;
76 	uint8_t			join_state;
77 	int			num_pend_reqs;
78 	struct list_head	pending;
79 };
80 
81 struct ib_sa_mcmember_data {
82 	union ib_gid	mgid;
83 	union ib_gid	port_gid;
84 	__be32		qkey;
85 	__be16		mlid;
86 	u8		mtusel_mtu;
87 	u8		tclass;
88 	__be16		pkey;
89 	u8		ratesel_rate;
90 	u8		lifetmsel_lifetm;
91 	__be32		sl_flowlabel_hoplimit;
92 	u8		scope_join_state;
93 	u8		proxy_join;
94 	u8		reserved[2];
95 };
96 
97 struct mcast_group {
98 	struct ib_sa_mcmember_data rec;
99 	struct rb_node		node;
100 	struct list_head	mgid0_list;
101 	struct mlx4_ib_demux_ctx *demux;
102 	struct mcast_member	func[MAX_VFS];
103 	struct mutex		lock;
104 	struct work_struct	work;
105 	struct list_head	pending_list;
106 	int			members[3];
107 	enum mcast_group_state	state;
108 	enum mcast_group_state	prev_state;
109 	struct ib_sa_mad	response_sa_mad;
110 	__be64			last_req_tid;
111 
112 	char			name[33]; /* MGID string */
113 	struct device_attribute	dentry;
114 
115 	/* refcount is the reference count for the following:
116 	   1. Each queued request
117 	   2. Each invocation of the worker thread
118 	   3. Membership of the port at the SA
119 	*/
120 	atomic_t		refcount;
121 
122 	/* delayed work to clean pending SM request */
123 	struct delayed_work	timeout_work;
124 	struct list_head	cleanup_list;
125 };
126 
127 struct mcast_req {
128 	int			func;
129 	struct ib_sa_mad	sa_mad;
130 	struct list_head	group_list;
131 	struct list_head	func_list;
132 	struct mcast_group	*group;
133 	int			clean;
134 };
135 
136 
137 #define safe_atomic_dec(ref) \
138 	do {\
139 		if (atomic_dec_and_test(ref)) \
140 			mcg_warn_group(group, "did not expect to reach zero\n"); \
141 	} while (0)
142 
143 static const char *get_state_string(enum mcast_group_state state)
144 {
145 	switch (state) {
146 	case MCAST_IDLE:
147 		return "MCAST_IDLE";
148 	case MCAST_JOIN_SENT:
149 		return "MCAST_JOIN_SENT";
150 	case MCAST_LEAVE_SENT:
151 		return "MCAST_LEAVE_SENT";
152 	case MCAST_RESP_READY:
153 		return "MCAST_RESP_READY";
154 	}
155 	return "Invalid State";
156 }
157 
158 static struct mcast_group *mcast_find(struct mlx4_ib_demux_ctx *ctx,
159 				      union ib_gid *mgid)
160 {
161 	struct rb_node *node = ctx->mcg_table.rb_node;
162 	struct mcast_group *group;
163 	int ret;
164 
165 	while (node) {
166 		group = rb_entry(node, struct mcast_group, node);
167 		ret = memcmp(mgid->raw, group->rec.mgid.raw, sizeof *mgid);
168 		if (!ret)
169 			return group;
170 
171 		if (ret < 0)
172 			node = node->rb_left;
173 		else
174 			node = node->rb_right;
175 	}
176 	return NULL;
177 }
178 
179 static struct mcast_group *mcast_insert(struct mlx4_ib_demux_ctx *ctx,
180 					struct mcast_group *group)
181 {
182 	struct rb_node **link = &ctx->mcg_table.rb_node;
183 	struct rb_node *parent = NULL;
184 	struct mcast_group *cur_group;
185 	int ret;
186 
187 	while (*link) {
188 		parent = *link;
189 		cur_group = rb_entry(parent, struct mcast_group, node);
190 
191 		ret = memcmp(group->rec.mgid.raw, cur_group->rec.mgid.raw,
192 			     sizeof group->rec.mgid);
193 		if (ret < 0)
194 			link = &(*link)->rb_left;
195 		else if (ret > 0)
196 			link = &(*link)->rb_right;
197 		else
198 			return cur_group;
199 	}
200 	rb_link_node(&group->node, parent, link);
201 	rb_insert_color(&group->node, &ctx->mcg_table);
202 	return NULL;
203 }
204 
205 static int send_mad_to_wire(struct mlx4_ib_demux_ctx *ctx, struct ib_mad *mad)
206 {
207 	struct mlx4_ib_dev *dev = ctx->dev;
208 	struct ib_ah_attr	ah_attr;
209 
210 	spin_lock(&dev->sm_lock);
211 	if (!dev->sm_ah[ctx->port - 1]) {
212 		/* port is not yet Active, sm_ah not ready */
213 		spin_unlock(&dev->sm_lock);
214 		return -EAGAIN;
215 	}
216 	mlx4_ib_query_ah(dev->sm_ah[ctx->port - 1], &ah_attr);
217 	spin_unlock(&dev->sm_lock);
218 	return mlx4_ib_send_to_wire(dev, mlx4_master_func_num(dev->dev),
219 				    ctx->port, IB_QPT_GSI, 0, 1, IB_QP1_QKEY,
220 				    &ah_attr, NULL, mad);
221 }
222 
223 static int send_mad_to_slave(int slave, struct mlx4_ib_demux_ctx *ctx,
224 			     struct ib_mad *mad)
225 {
226 	struct mlx4_ib_dev *dev = ctx->dev;
227 	struct ib_mad_agent *agent = dev->send_agent[ctx->port - 1][1];
228 	struct ib_wc wc;
229 	struct ib_ah_attr ah_attr;
230 
231 	/* Our agent might not yet be registered when mads start to arrive */
232 	if (!agent)
233 		return -EAGAIN;
234 
235 	ib_query_ah(dev->sm_ah[ctx->port - 1], &ah_attr);
236 
237 	if (ib_find_cached_pkey(&dev->ib_dev, ctx->port, IB_DEFAULT_PKEY_FULL, &wc.pkey_index))
238 		return -EINVAL;
239 	wc.sl = 0;
240 	wc.dlid_path_bits = 0;
241 	wc.port_num = ctx->port;
242 	wc.slid = ah_attr.dlid;  /* opensm lid */
243 	wc.src_qp = 1;
244 	return mlx4_ib_send_to_slave(dev, slave, ctx->port, IB_QPT_GSI, &wc, NULL, mad);
245 }
246 
247 static int send_join_to_wire(struct mcast_group *group, struct ib_sa_mad *sa_mad)
248 {
249 	struct ib_sa_mad mad;
250 	struct ib_sa_mcmember_data *sa_mad_data = (struct ib_sa_mcmember_data *)&mad.data;
251 	int ret;
252 
253 	/* we rely on a mad request as arrived from a VF */
254 	memcpy(&mad, sa_mad, sizeof mad);
255 
256 	/* fix port GID to be the real one (slave 0) */
257 	sa_mad_data->port_gid.global.interface_id = group->demux->guid_cache[0];
258 
259 	/* assign our own TID */
260 	mad.mad_hdr.tid = mlx4_ib_get_new_demux_tid(group->demux);
261 	group->last_req_tid = mad.mad_hdr.tid; /* keep it for later validation */
262 
263 	ret = send_mad_to_wire(group->demux, (struct ib_mad *)&mad);
264 	/* set timeout handler */
265 	if (!ret) {
266 		/* calls mlx4_ib_mcg_timeout_handler */
267 		queue_delayed_work(group->demux->mcg_wq, &group->timeout_work,
268 				msecs_to_jiffies(MAD_TIMEOUT_MS));
269 	}
270 
271 	return ret;
272 }
273 
274 static int send_leave_to_wire(struct mcast_group *group, u8 join_state)
275 {
276 	struct ib_sa_mad mad;
277 	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)&mad.data;
278 	int ret;
279 
280 	memset(&mad, 0, sizeof mad);
281 	mad.mad_hdr.base_version = 1;
282 	mad.mad_hdr.mgmt_class = IB_MGMT_CLASS_SUBN_ADM;
283 	mad.mad_hdr.class_version = 2;
284 	mad.mad_hdr.method = IB_SA_METHOD_DELETE;
285 	mad.mad_hdr.status = cpu_to_be16(0);
286 	mad.mad_hdr.class_specific = cpu_to_be16(0);
287 	mad.mad_hdr.tid = mlx4_ib_get_new_demux_tid(group->demux);
288 	group->last_req_tid = mad.mad_hdr.tid; /* keep it for later validation */
289 	mad.mad_hdr.attr_id = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
290 	mad.mad_hdr.attr_mod = cpu_to_be32(0);
291 	mad.sa_hdr.sm_key = 0x0;
292 	mad.sa_hdr.attr_offset = cpu_to_be16(7);
293 	mad.sa_hdr.comp_mask = IB_SA_MCMEMBER_REC_MGID |
294 		IB_SA_MCMEMBER_REC_PORT_GID | IB_SA_MCMEMBER_REC_JOIN_STATE;
295 
296 	*sa_data = group->rec;
297 	sa_data->scope_join_state = join_state;
298 
299 	ret = send_mad_to_wire(group->demux, (struct ib_mad *)&mad);
300 	if (ret)
301 		group->state = MCAST_IDLE;
302 
303 	/* set timeout handler */
304 	if (!ret) {
305 		/* calls mlx4_ib_mcg_timeout_handler */
306 		queue_delayed_work(group->demux->mcg_wq, &group->timeout_work,
307 				msecs_to_jiffies(MAD_TIMEOUT_MS));
308 	}
309 
310 	return ret;
311 }
312 
313 static int send_reply_to_slave(int slave, struct mcast_group *group,
314 		struct ib_sa_mad *req_sa_mad, u16 status)
315 {
316 	struct ib_sa_mad mad;
317 	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)&mad.data;
318 	struct ib_sa_mcmember_data *req_sa_data = (struct ib_sa_mcmember_data *)&req_sa_mad->data;
319 	int ret;
320 
321 	memset(&mad, 0, sizeof mad);
322 	mad.mad_hdr.base_version = 1;
323 	mad.mad_hdr.mgmt_class = IB_MGMT_CLASS_SUBN_ADM;
324 	mad.mad_hdr.class_version = 2;
325 	mad.mad_hdr.method = IB_MGMT_METHOD_GET_RESP;
326 	mad.mad_hdr.status = cpu_to_be16(status);
327 	mad.mad_hdr.class_specific = cpu_to_be16(0);
328 	mad.mad_hdr.tid = req_sa_mad->mad_hdr.tid;
329 	*(u8 *)&mad.mad_hdr.tid = 0; /* resetting tid to 0 */
330 	mad.mad_hdr.attr_id = cpu_to_be16(IB_SA_ATTR_MC_MEMBER_REC);
331 	mad.mad_hdr.attr_mod = cpu_to_be32(0);
332 	mad.sa_hdr.sm_key = req_sa_mad->sa_hdr.sm_key;
333 	mad.sa_hdr.attr_offset = cpu_to_be16(7);
334 	mad.sa_hdr.comp_mask = 0; /* ignored on responses, see IBTA spec */
335 
336 	*sa_data = group->rec;
337 
338 	/* reconstruct VF's requested join_state and port_gid */
339 	sa_data->scope_join_state &= 0xf0;
340 	sa_data->scope_join_state |= (group->func[slave].join_state & 0x0f);
341 	memcpy(&sa_data->port_gid, &req_sa_data->port_gid, sizeof req_sa_data->port_gid);
342 
343 	ret = send_mad_to_slave(slave, group->demux, (struct ib_mad *)&mad);
344 	return ret;
345 }
346 
347 static int check_selector(ib_sa_comp_mask comp_mask,
348 			  ib_sa_comp_mask selector_mask,
349 			  ib_sa_comp_mask value_mask,
350 			  u8 src_value, u8 dst_value)
351 {
352 	int err;
353 	u8 selector = dst_value >> 6;
354 	dst_value &= 0x3f;
355 	src_value &= 0x3f;
356 
357 	if (!(comp_mask & selector_mask) || !(comp_mask & value_mask))
358 		return 0;
359 
360 	switch (selector) {
361 	case IB_SA_GT:
362 		err = (src_value <= dst_value);
363 		break;
364 	case IB_SA_LT:
365 		err = (src_value >= dst_value);
366 		break;
367 	case IB_SA_EQ:
368 		err = (src_value != dst_value);
369 		break;
370 	default:
371 		err = 0;
372 		break;
373 	}
374 
375 	return err;
376 }
377 
378 static u16 cmp_rec(struct ib_sa_mcmember_data *src,
379 		   struct ib_sa_mcmember_data *dst, ib_sa_comp_mask comp_mask)
380 {
381 	/* src is group record, dst is request record */
382 	/* MGID must already match */
383 	/* Port_GID we always replace to our Port_GID, so it is a match */
384 
385 #define MAD_STATUS_REQ_INVALID 0x0200
386 	if (comp_mask & IB_SA_MCMEMBER_REC_QKEY && src->qkey != dst->qkey)
387 		return MAD_STATUS_REQ_INVALID;
388 	if (comp_mask & IB_SA_MCMEMBER_REC_MLID && src->mlid != dst->mlid)
389 		return MAD_STATUS_REQ_INVALID;
390 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_MTU_SELECTOR,
391 				 IB_SA_MCMEMBER_REC_MTU,
392 				 src->mtusel_mtu, dst->mtusel_mtu))
393 		return MAD_STATUS_REQ_INVALID;
394 	if (comp_mask & IB_SA_MCMEMBER_REC_TRAFFIC_CLASS &&
395 	    src->tclass != dst->tclass)
396 		return MAD_STATUS_REQ_INVALID;
397 	if (comp_mask & IB_SA_MCMEMBER_REC_PKEY && src->pkey != dst->pkey)
398 		return MAD_STATUS_REQ_INVALID;
399 	if (check_selector(comp_mask, IB_SA_MCMEMBER_REC_RATE_SELECTOR,
400 				 IB_SA_MCMEMBER_REC_RATE,
401 				 src->ratesel_rate, dst->ratesel_rate))
402 		return MAD_STATUS_REQ_INVALID;
403 	if (check_selector(comp_mask,
404 				 IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME_SELECTOR,
405 				 IB_SA_MCMEMBER_REC_PACKET_LIFE_TIME,
406 				 src->lifetmsel_lifetm, dst->lifetmsel_lifetm))
407 		return MAD_STATUS_REQ_INVALID;
408 	if (comp_mask & IB_SA_MCMEMBER_REC_SL &&
409 			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0xf0000000) !=
410 			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0xf0000000))
411 		return MAD_STATUS_REQ_INVALID;
412 	if (comp_mask & IB_SA_MCMEMBER_REC_FLOW_LABEL &&
413 			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0x0fffff00) !=
414 			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0x0fffff00))
415 		return MAD_STATUS_REQ_INVALID;
416 	if (comp_mask & IB_SA_MCMEMBER_REC_HOP_LIMIT &&
417 			(be32_to_cpu(src->sl_flowlabel_hoplimit) & 0x000000ff) !=
418 			(be32_to_cpu(dst->sl_flowlabel_hoplimit) & 0x000000ff))
419 		return MAD_STATUS_REQ_INVALID;
420 	if (comp_mask & IB_SA_MCMEMBER_REC_SCOPE &&
421 			(src->scope_join_state & 0xf0) !=
422 			(dst->scope_join_state & 0xf0))
423 		return MAD_STATUS_REQ_INVALID;
424 
425 	/* join_state checked separately, proxy_join ignored */
426 
427 	return 0;
428 }
429 
430 /* release group, return 1 if this was last release and group is destroyed
431  * timout work is canceled sync */
432 static int release_group(struct mcast_group *group, int from_timeout_handler)
433 {
434 	struct mlx4_ib_demux_ctx *ctx = group->demux;
435 	int nzgroup;
436 
437 	mutex_lock(&ctx->mcg_table_lock);
438 	mutex_lock(&group->lock);
439 	if (atomic_dec_and_test(&group->refcount)) {
440 		if (!from_timeout_handler) {
441 			if (group->state != MCAST_IDLE &&
442 			    !cancel_delayed_work(&group->timeout_work)) {
443 				atomic_inc(&group->refcount);
444 				mutex_unlock(&group->lock);
445 				mutex_unlock(&ctx->mcg_table_lock);
446 				return 0;
447 			}
448 		}
449 
450 		nzgroup = memcmp(&group->rec.mgid, &mgid0, sizeof mgid0);
451 		if (nzgroup)
452 			del_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
453 		if (!list_empty(&group->pending_list))
454 			mcg_warn_group(group, "releasing a group with non empty pending list\n");
455 		if (nzgroup)
456 			rb_erase(&group->node, &ctx->mcg_table);
457 		list_del_init(&group->mgid0_list);
458 		mutex_unlock(&group->lock);
459 		mutex_unlock(&ctx->mcg_table_lock);
460 		kfree(group);
461 		return 1;
462 	} else {
463 		mutex_unlock(&group->lock);
464 		mutex_unlock(&ctx->mcg_table_lock);
465 	}
466 	return 0;
467 }
468 
469 static void adjust_membership(struct mcast_group *group, u8 join_state, int inc)
470 {
471 	int i;
472 
473 	for (i = 0; i < 3; i++, join_state >>= 1)
474 		if (join_state & 0x1)
475 			group->members[i] += inc;
476 }
477 
478 static u8 get_leave_state(struct mcast_group *group)
479 {
480 	u8 leave_state = 0;
481 	int i;
482 
483 	for (i = 0; i < 3; i++)
484 		if (!group->members[i])
485 			leave_state |= (1 << i);
486 
487 	return leave_state & (group->rec.scope_join_state & 7);
488 }
489 
490 static int join_group(struct mcast_group *group, int slave, u8 join_mask)
491 {
492 	int ret = 0;
493 	u8 join_state;
494 
495 	/* remove bits that slave is already member of, and adjust */
496 	join_state = join_mask & (~group->func[slave].join_state);
497 	adjust_membership(group, join_state, 1);
498 	group->func[slave].join_state |= join_state;
499 	if (group->func[slave].state != MCAST_MEMBER && join_state) {
500 		group->func[slave].state = MCAST_MEMBER;
501 		ret = 1;
502 	}
503 	return ret;
504 }
505 
506 static int leave_group(struct mcast_group *group, int slave, u8 leave_state)
507 {
508 	int ret = 0;
509 
510 	adjust_membership(group, leave_state, -1);
511 	group->func[slave].join_state &= ~leave_state;
512 	if (!group->func[slave].join_state) {
513 		group->func[slave].state = MCAST_NOT_MEMBER;
514 		ret = 1;
515 	}
516 	return ret;
517 }
518 
519 static int check_leave(struct mcast_group *group, int slave, u8 leave_mask)
520 {
521 	if (group->func[slave].state != MCAST_MEMBER)
522 		return MAD_STATUS_REQ_INVALID;
523 
524 	/* make sure we're not deleting unset bits */
525 	if (~group->func[slave].join_state & leave_mask)
526 		return MAD_STATUS_REQ_INVALID;
527 
528 	if (!leave_mask)
529 		return MAD_STATUS_REQ_INVALID;
530 
531 	return 0;
532 }
533 
534 static void mlx4_ib_mcg_timeout_handler(struct work_struct *work)
535 {
536 	struct delayed_work *delay = to_delayed_work(work);
537 	struct mcast_group *group;
538 	struct mcast_req *req = NULL;
539 
540 	group = container_of(delay, typeof(*group), timeout_work);
541 
542 	mutex_lock(&group->lock);
543 	if (group->state == MCAST_JOIN_SENT) {
544 		if (!list_empty(&group->pending_list)) {
545 			req = list_first_entry(&group->pending_list, struct mcast_req, group_list);
546 			list_del(&req->group_list);
547 			list_del(&req->func_list);
548 			--group->func[req->func].num_pend_reqs;
549 			mutex_unlock(&group->lock);
550 			kfree(req);
551 			if (memcmp(&group->rec.mgid, &mgid0, sizeof mgid0)) {
552 				if (release_group(group, 1))
553 					return;
554 			} else {
555 				kfree(group);
556 				return;
557 			}
558 			mutex_lock(&group->lock);
559 		} else
560 			mcg_warn_group(group, "DRIVER BUG\n");
561 	} else if (group->state == MCAST_LEAVE_SENT) {
562 		if (group->rec.scope_join_state & 7)
563 			group->rec.scope_join_state &= 0xf8;
564 		group->state = MCAST_IDLE;
565 		mutex_unlock(&group->lock);
566 		if (release_group(group, 1))
567 			return;
568 		mutex_lock(&group->lock);
569 	} else
570 		mcg_warn_group(group, "invalid state %s\n", get_state_string(group->state));
571 	group->state = MCAST_IDLE;
572 	atomic_inc(&group->refcount);
573 	if (!queue_work(group->demux->mcg_wq, &group->work))
574 		safe_atomic_dec(&group->refcount);
575 
576 	mutex_unlock(&group->lock);
577 }
578 
579 static int handle_leave_req(struct mcast_group *group, u8 leave_mask,
580 			    struct mcast_req *req)
581 {
582 	u16 status;
583 
584 	if (req->clean)
585 		leave_mask = group->func[req->func].join_state;
586 
587 	status = check_leave(group, req->func, leave_mask);
588 	if (!status)
589 		leave_group(group, req->func, leave_mask);
590 
591 	if (!req->clean)
592 		send_reply_to_slave(req->func, group, &req->sa_mad, status);
593 	--group->func[req->func].num_pend_reqs;
594 	list_del(&req->group_list);
595 	list_del(&req->func_list);
596 	kfree(req);
597 	return 1;
598 }
599 
600 static int handle_join_req(struct mcast_group *group, u8 join_mask,
601 			   struct mcast_req *req)
602 {
603 	u8 group_join_state = group->rec.scope_join_state & 7;
604 	int ref = 0;
605 	u16 status;
606 	struct ib_sa_mcmember_data *sa_data = (struct ib_sa_mcmember_data *)req->sa_mad.data;
607 
608 	if (join_mask == (group_join_state & join_mask)) {
609 		/* port's membership need not change */
610 		status = cmp_rec(&group->rec, sa_data, req->sa_mad.sa_hdr.comp_mask);
611 		if (!status)
612 			join_group(group, req->func, join_mask);
613 
614 		--group->func[req->func].num_pend_reqs;
615 		send_reply_to_slave(req->func, group, &req->sa_mad, status);
616 		list_del(&req->group_list);
617 		list_del(&req->func_list);
618 		kfree(req);
619 		++ref;
620 	} else {
621 		/* port's membership needs to be updated */
622 		group->prev_state = group->state;
623 		if (send_join_to_wire(group, &req->sa_mad)) {
624 			--group->func[req->func].num_pend_reqs;
625 			list_del(&req->group_list);
626 			list_del(&req->func_list);
627 			kfree(req);
628 			ref = 1;
629 			group->state = group->prev_state;
630 		} else
631 			group->state = MCAST_JOIN_SENT;
632 	}
633 
634 	return ref;
635 }
636 
637 static void mlx4_ib_mcg_work_handler(struct work_struct *work)
638 {
639 	struct mcast_group *group;
640 	struct mcast_req *req = NULL;
641 	struct ib_sa_mcmember_data *sa_data;
642 	u8 req_join_state;
643 	int rc = 1; /* release_count - this is for the scheduled work */
644 	u16 status;
645 	u8 method;
646 
647 	group = container_of(work, typeof(*group), work);
648 
649 	mutex_lock(&group->lock);
650 
651 	/* First, let's see if a response from SM is waiting regarding this group.
652 	 * If so, we need to update the group's REC. If this is a bad response, we
653 	 * may need to send a bad response to a VF waiting for it. If VF is waiting
654 	 * and this is a good response, the VF will be answered later in this func. */
655 	if (group->state == MCAST_RESP_READY) {
656 		/* cancels mlx4_ib_mcg_timeout_handler */
657 		cancel_delayed_work(&group->timeout_work);
658 		status = be16_to_cpu(group->response_sa_mad.mad_hdr.status);
659 		method = group->response_sa_mad.mad_hdr.method;
660 		if (group->last_req_tid != group->response_sa_mad.mad_hdr.tid) {
661 			mcg_warn_group(group, "Got MAD response to existing MGID but wrong TID, dropping. Resp TID=%llx, group TID=%llx\n",
662 				be64_to_cpu(group->response_sa_mad.mad_hdr.tid),
663 				be64_to_cpu(group->last_req_tid));
664 			group->state = group->prev_state;
665 			goto process_requests;
666 		}
667 		if (status) {
668 			if (!list_empty(&group->pending_list))
669 				req = list_first_entry(&group->pending_list,
670 						struct mcast_req, group_list);
671 			if ((method == IB_MGMT_METHOD_GET_RESP)) {
672 					if (req) {
673 						send_reply_to_slave(req->func, group, &req->sa_mad, status);
674 						--group->func[req->func].num_pend_reqs;
675 						list_del(&req->group_list);
676 						list_del(&req->func_list);
677 						kfree(req);
678 						++rc;
679 					} else
680 						mcg_warn_group(group, "no request for failed join\n");
681 			} else if (method == IB_SA_METHOD_DELETE_RESP && group->demux->flushing)
682 				++rc;
683 		} else {
684 			u8 resp_join_state;
685 			u8 cur_join_state;
686 
687 			resp_join_state = ((struct ib_sa_mcmember_data *)
688 						group->response_sa_mad.data)->scope_join_state & 7;
689 			cur_join_state = group->rec.scope_join_state & 7;
690 
691 			if (method == IB_MGMT_METHOD_GET_RESP) {
692 				/* successfull join */
693 				if (!cur_join_state && resp_join_state)
694 					--rc;
695 			} else if (!resp_join_state)
696 					++rc;
697 			memcpy(&group->rec, group->response_sa_mad.data, sizeof group->rec);
698 		}
699 		group->state = MCAST_IDLE;
700 	}
701 
702 process_requests:
703 	/* We should now go over pending join/leave requests, as long as we are idle. */
704 	while (!list_empty(&group->pending_list) && group->state == MCAST_IDLE) {
705 		req = list_first_entry(&group->pending_list, struct mcast_req,
706 				       group_list);
707 		sa_data = (struct ib_sa_mcmember_data *)req->sa_mad.data;
708 		req_join_state = sa_data->scope_join_state & 0x7;
709 
710 		/* For a leave request, we will immediately answer the VF, and
711 		 * update our internal counters. The actual leave will be sent
712 		 * to SM later, if at all needed. We dequeue the request now. */
713 		if (req->sa_mad.mad_hdr.method == IB_SA_METHOD_DELETE)
714 			rc += handle_leave_req(group, req_join_state, req);
715 		else
716 			rc += handle_join_req(group, req_join_state, req);
717 	}
718 
719 	/* Handle leaves */
720 	if (group->state == MCAST_IDLE) {
721 		req_join_state = get_leave_state(group);
722 		if (req_join_state) {
723 			group->rec.scope_join_state &= ~req_join_state;
724 			group->prev_state = group->state;
725 			if (send_leave_to_wire(group, req_join_state)) {
726 				group->state = group->prev_state;
727 				++rc;
728 			} else
729 				group->state = MCAST_LEAVE_SENT;
730 		}
731 	}
732 
733 	if (!list_empty(&group->pending_list) && group->state == MCAST_IDLE)
734 		goto process_requests;
735 	mutex_unlock(&group->lock);
736 
737 	while (rc--)
738 		release_group(group, 0);
739 }
740 
741 static struct mcast_group *search_relocate_mgid0_group(struct mlx4_ib_demux_ctx *ctx,
742 						       __be64 tid,
743 						       union ib_gid *new_mgid)
744 {
745 	struct mcast_group *group = NULL, *cur_group;
746 	struct mcast_req *req;
747 	struct list_head *pos;
748 	struct list_head *n;
749 
750 	mutex_lock(&ctx->mcg_table_lock);
751 	list_for_each_safe(pos, n, &ctx->mcg_mgid0_list) {
752 		group = list_entry(pos, struct mcast_group, mgid0_list);
753 		mutex_lock(&group->lock);
754 		if (group->last_req_tid == tid) {
755 			if (memcmp(new_mgid, &mgid0, sizeof mgid0)) {
756 				group->rec.mgid = *new_mgid;
757 				sprintf(group->name, "%016llx%016llx",
758 						be64_to_cpu(group->rec.mgid.global.subnet_prefix),
759 						be64_to_cpu(group->rec.mgid.global.interface_id));
760 				list_del_init(&group->mgid0_list);
761 				cur_group = mcast_insert(ctx, group);
762 				if (cur_group) {
763 					/* A race between our code and SM. Silently cleaning the new one */
764 					req = list_first_entry(&group->pending_list,
765 							       struct mcast_req, group_list);
766 					--group->func[req->func].num_pend_reqs;
767 					list_del(&req->group_list);
768 					list_del(&req->func_list);
769 					kfree(req);
770 					mutex_unlock(&group->lock);
771 					mutex_unlock(&ctx->mcg_table_lock);
772 					release_group(group, 0);
773 					return NULL;
774 				}
775 
776 				atomic_inc(&group->refcount);
777 				add_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
778 				mutex_unlock(&group->lock);
779 				mutex_unlock(&ctx->mcg_table_lock);
780 				return group;
781 			} else {
782 				struct mcast_req *tmp1, *tmp2;
783 
784 				list_del(&group->mgid0_list);
785 				if (!list_empty(&group->pending_list) && group->state != MCAST_IDLE)
786 					cancel_delayed_work_sync(&group->timeout_work);
787 
788 				list_for_each_entry_safe(tmp1, tmp2, &group->pending_list, group_list) {
789 					list_del(&tmp1->group_list);
790 					kfree(tmp1);
791 				}
792 				mutex_unlock(&group->lock);
793 				mutex_unlock(&ctx->mcg_table_lock);
794 				kfree(group);
795 				return NULL;
796 			}
797 		}
798 		mutex_unlock(&group->lock);
799 	}
800 	mutex_unlock(&ctx->mcg_table_lock);
801 
802 	return NULL;
803 }
804 
805 static ssize_t sysfs_show_group(struct device *dev,
806 		struct device_attribute *attr, char *buf);
807 
808 static struct mcast_group *acquire_group(struct mlx4_ib_demux_ctx *ctx,
809 					 union ib_gid *mgid, int create,
810 					 gfp_t gfp_mask)
811 {
812 	struct mcast_group *group, *cur_group;
813 	int is_mgid0;
814 	int i;
815 
816 	is_mgid0 = !memcmp(&mgid0, mgid, sizeof mgid0);
817 	if (!is_mgid0) {
818 		group = mcast_find(ctx, mgid);
819 		if (group)
820 			goto found;
821 	}
822 
823 	if (!create)
824 		return ERR_PTR(-ENOENT);
825 
826 	group = kzalloc(sizeof *group, gfp_mask);
827 	if (!group)
828 		return ERR_PTR(-ENOMEM);
829 
830 	group->demux = ctx;
831 	group->rec.mgid = *mgid;
832 	INIT_LIST_HEAD(&group->pending_list);
833 	INIT_LIST_HEAD(&group->mgid0_list);
834 	for (i = 0; i < MAX_VFS; ++i)
835 		INIT_LIST_HEAD(&group->func[i].pending);
836 	INIT_WORK(&group->work, mlx4_ib_mcg_work_handler);
837 	INIT_DELAYED_WORK(&group->timeout_work, mlx4_ib_mcg_timeout_handler);
838 	mutex_init(&group->lock);
839 	sprintf(group->name, "%016llx%016llx",
840 			be64_to_cpu(group->rec.mgid.global.subnet_prefix),
841 			be64_to_cpu(group->rec.mgid.global.interface_id));
842 	sysfs_attr_init(&group->dentry.attr);
843 	group->dentry.show = sysfs_show_group;
844 	group->dentry.store = NULL;
845 	group->dentry.attr.name = group->name;
846 	group->dentry.attr.mode = 0400;
847 	group->state = MCAST_IDLE;
848 
849 	if (is_mgid0) {
850 		list_add(&group->mgid0_list, &ctx->mcg_mgid0_list);
851 		goto found;
852 	}
853 
854 	cur_group = mcast_insert(ctx, group);
855 	if (cur_group) {
856 		mcg_warn("group just showed up %s - confused\n", cur_group->name);
857 		kfree(group);
858 		return ERR_PTR(-EINVAL);
859 	}
860 
861 	add_sysfs_port_mcg_attr(ctx->dev, ctx->port, &group->dentry.attr);
862 
863 found:
864 	atomic_inc(&group->refcount);
865 	return group;
866 }
867 
868 static void queue_req(struct mcast_req *req)
869 {
870 	struct mcast_group *group = req->group;
871 
872 	atomic_inc(&group->refcount); /* for the request */
873 	atomic_inc(&group->refcount); /* for scheduling the work */
874 	list_add_tail(&req->group_list, &group->pending_list);
875 	list_add_tail(&req->func_list, &group->func[req->func].pending);
876 	/* calls mlx4_ib_mcg_work_handler */
877 	if (!queue_work(group->demux->mcg_wq, &group->work))
878 		safe_atomic_dec(&group->refcount);
879 }
880 
881 int mlx4_ib_mcg_demux_handler(struct ib_device *ibdev, int port, int slave,
882 			      struct ib_sa_mad *mad)
883 {
884 	struct mlx4_ib_dev *dev = to_mdev(ibdev);
885 	struct ib_sa_mcmember_data *rec = (struct ib_sa_mcmember_data *)mad->data;
886 	struct mlx4_ib_demux_ctx *ctx = &dev->sriov.demux[port - 1];
887 	struct mcast_group *group;
888 
889 	switch (mad->mad_hdr.method) {
890 	case IB_MGMT_METHOD_GET_RESP:
891 	case IB_SA_METHOD_DELETE_RESP:
892 		mutex_lock(&ctx->mcg_table_lock);
893 		group = acquire_group(ctx, &rec->mgid, 0, GFP_KERNEL);
894 		mutex_unlock(&ctx->mcg_table_lock);
895 		if (IS_ERR(group)) {
896 			if (mad->mad_hdr.method == IB_MGMT_METHOD_GET_RESP) {
897 				__be64 tid = mad->mad_hdr.tid;
898 				*(u8 *)(&tid) = (u8)slave; /* in group we kept the modified TID */
899 				group = search_relocate_mgid0_group(ctx, tid, &rec->mgid);
900 			} else
901 				group = NULL;
902 		}
903 
904 		if (!group)
905 			return 1;
906 
907 		mutex_lock(&group->lock);
908 		group->response_sa_mad = *mad;
909 		group->prev_state = group->state;
910 		group->state = MCAST_RESP_READY;
911 		/* calls mlx4_ib_mcg_work_handler */
912 		atomic_inc(&group->refcount);
913 		if (!queue_work(ctx->mcg_wq, &group->work))
914 			safe_atomic_dec(&group->refcount);
915 		mutex_unlock(&group->lock);
916 		release_group(group, 0);
917 		return 1; /* consumed */
918 	case IB_MGMT_METHOD_SET:
919 	case IB_SA_METHOD_GET_TABLE:
920 	case IB_SA_METHOD_GET_TABLE_RESP:
921 	case IB_SA_METHOD_DELETE:
922 		return 0; /* not consumed, pass-through to guest over tunnel */
923 	default:
924 		mcg_warn("In demux, port %d: unexpected MCMember method: 0x%x, dropping\n",
925 			port, mad->mad_hdr.method);
926 		return 1; /* consumed */
927 	}
928 }
929 
930 int mlx4_ib_mcg_multiplex_handler(struct ib_device *ibdev, int port,
931 				  int slave, struct ib_sa_mad *sa_mad)
932 {
933 	struct mlx4_ib_dev *dev = to_mdev(ibdev);
934 	struct ib_sa_mcmember_data *rec = (struct ib_sa_mcmember_data *)sa_mad->data;
935 	struct mlx4_ib_demux_ctx *ctx = &dev->sriov.demux[port - 1];
936 	struct mcast_group *group;
937 	struct mcast_req *req;
938 	int may_create = 0;
939 
940 	if (ctx->flushing)
941 		return -EAGAIN;
942 
943 	switch (sa_mad->mad_hdr.method) {
944 	case IB_MGMT_METHOD_SET:
945 		may_create = 1;
946 	case IB_SA_METHOD_DELETE:
947 		req = kzalloc(sizeof *req, GFP_KERNEL);
948 		if (!req)
949 			return -ENOMEM;
950 
951 		req->func = slave;
952 		req->sa_mad = *sa_mad;
953 
954 		mutex_lock(&ctx->mcg_table_lock);
955 		group = acquire_group(ctx, &rec->mgid, may_create, GFP_KERNEL);
956 		mutex_unlock(&ctx->mcg_table_lock);
957 		if (IS_ERR(group)) {
958 			kfree(req);
959 			return PTR_ERR(group);
960 		}
961 		mutex_lock(&group->lock);
962 		if (group->func[slave].num_pend_reqs > MAX_PEND_REQS_PER_FUNC) {
963 			mutex_unlock(&group->lock);
964 			mcg_warn_group(group, "Port %d, Func %d has too many pending requests (%d), dropping\n",
965 				       port, slave, MAX_PEND_REQS_PER_FUNC);
966 			release_group(group, 0);
967 			kfree(req);
968 			return -ENOMEM;
969 		}
970 		++group->func[slave].num_pend_reqs;
971 		req->group = group;
972 		queue_req(req);
973 		mutex_unlock(&group->lock);
974 		release_group(group, 0);
975 		return 1; /* consumed */
976 	case IB_SA_METHOD_GET_TABLE:
977 	case IB_MGMT_METHOD_GET_RESP:
978 	case IB_SA_METHOD_GET_TABLE_RESP:
979 	case IB_SA_METHOD_DELETE_RESP:
980 		return 0; /* not consumed, pass-through */
981 	default:
982 		mcg_warn("In multiplex, port %d, func %d: unexpected MCMember method: 0x%x, dropping\n",
983 			port, slave, sa_mad->mad_hdr.method);
984 		return 1; /* consumed */
985 	}
986 }
987 
988 static ssize_t sysfs_show_group(struct device *dev,
989 		struct device_attribute *attr, char *buf)
990 {
991 	struct mcast_group *group =
992 		container_of(attr, struct mcast_group, dentry);
993 	struct mcast_req *req = NULL;
994 	char pending_str[40];
995 	char state_str[40];
996 	ssize_t len = 0;
997 	int f;
998 
999 	if (group->state == MCAST_IDLE)
1000 		sprintf(state_str, "%s", get_state_string(group->state));
1001 	else
1002 		sprintf(state_str, "%s(TID=0x%llx)",
1003 				get_state_string(group->state),
1004 				be64_to_cpu(group->last_req_tid));
1005 	if (list_empty(&group->pending_list)) {
1006 		sprintf(pending_str, "No");
1007 	} else {
1008 		req = list_first_entry(&group->pending_list, struct mcast_req, group_list);
1009 		sprintf(pending_str, "Yes(TID=0x%llx)",
1010 				be64_to_cpu(req->sa_mad.mad_hdr.tid));
1011 	}
1012 	len += sprintf(buf + len, "%1d [%02d,%02d,%02d] %4d %4s %5s     ",
1013 			group->rec.scope_join_state & 0xf,
1014 			group->members[2], group->members[1], group->members[0],
1015 			atomic_read(&group->refcount),
1016 			pending_str,
1017 			state_str);
1018 	for (f = 0; f < MAX_VFS; ++f)
1019 		if (group->func[f].state == MCAST_MEMBER)
1020 			len += sprintf(buf + len, "%d[%1x] ",
1021 					f, group->func[f].join_state);
1022 
1023 	len += sprintf(buf + len, "\t\t(%4hx %4x %2x %2x %2x %2x %2x "
1024 		"%4x %4x %2x %2x)\n",
1025 		be16_to_cpu(group->rec.pkey),
1026 		be32_to_cpu(group->rec.qkey),
1027 		(group->rec.mtusel_mtu & 0xc0) >> 6,
1028 		group->rec.mtusel_mtu & 0x3f,
1029 		group->rec.tclass,
1030 		(group->rec.ratesel_rate & 0xc0) >> 6,
1031 		group->rec.ratesel_rate & 0x3f,
1032 		(be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0xf0000000) >> 28,
1033 		(be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0x0fffff00) >> 8,
1034 		be32_to_cpu(group->rec.sl_flowlabel_hoplimit) & 0x000000ff,
1035 		group->rec.proxy_join);
1036 
1037 	return len;
1038 }
1039 
1040 int mlx4_ib_mcg_port_init(struct mlx4_ib_demux_ctx *ctx)
1041 {
1042 	char name[20];
1043 
1044 	atomic_set(&ctx->tid, 0);
1045 	sprintf(name, "mlx4_ib_mcg%d", ctx->port);
1046 	ctx->mcg_wq = create_singlethread_workqueue(name);
1047 	if (!ctx->mcg_wq)
1048 		return -ENOMEM;
1049 
1050 	mutex_init(&ctx->mcg_table_lock);
1051 	ctx->mcg_table = RB_ROOT;
1052 	INIT_LIST_HEAD(&ctx->mcg_mgid0_list);
1053 	ctx->flushing = 0;
1054 
1055 	return 0;
1056 }
1057 
1058 static void force_clean_group(struct mcast_group *group)
1059 {
1060 	struct mcast_req *req, *tmp
1061 		;
1062 	list_for_each_entry_safe(req, tmp, &group->pending_list, group_list) {
1063 		list_del(&req->group_list);
1064 		kfree(req);
1065 	}
1066 	del_sysfs_port_mcg_attr(group->demux->dev, group->demux->port, &group->dentry.attr);
1067 	rb_erase(&group->node, &group->demux->mcg_table);
1068 	kfree(group);
1069 }
1070 
1071 static void _mlx4_ib_mcg_port_cleanup(struct mlx4_ib_demux_ctx *ctx, int destroy_wq)
1072 {
1073 	int i;
1074 	struct rb_node *p;
1075 	struct mcast_group *group;
1076 	unsigned long end;
1077 	int count;
1078 
1079 	for (i = 0; i < MAX_VFS; ++i)
1080 		clean_vf_mcast(ctx, i);
1081 
1082 	end = jiffies + msecs_to_jiffies(MAD_TIMEOUT_MS + 3000);
1083 	do {
1084 		count = 0;
1085 		mutex_lock(&ctx->mcg_table_lock);
1086 		for (p = rb_first(&ctx->mcg_table); p; p = rb_next(p))
1087 			++count;
1088 		mutex_unlock(&ctx->mcg_table_lock);
1089 		if (!count)
1090 			break;
1091 
1092 		msleep(1);
1093 	} while (time_after(end, jiffies));
1094 
1095 	flush_workqueue(ctx->mcg_wq);
1096 	if (destroy_wq)
1097 		destroy_workqueue(ctx->mcg_wq);
1098 
1099 	mutex_lock(&ctx->mcg_table_lock);
1100 	while ((p = rb_first(&ctx->mcg_table)) != NULL) {
1101 		group = rb_entry(p, struct mcast_group, node);
1102 		if (atomic_read(&group->refcount))
1103 			mcg_warn_group(group, "group refcount %d!!! (pointer %p)\n", atomic_read(&group->refcount), group);
1104 
1105 		force_clean_group(group);
1106 	}
1107 	mutex_unlock(&ctx->mcg_table_lock);
1108 }
1109 
1110 struct clean_work {
1111 	struct work_struct work;
1112 	struct mlx4_ib_demux_ctx *ctx;
1113 	int destroy_wq;
1114 };
1115 
1116 static void mcg_clean_task(struct work_struct *work)
1117 {
1118 	struct clean_work *cw = container_of(work, struct clean_work, work);
1119 
1120 	_mlx4_ib_mcg_port_cleanup(cw->ctx, cw->destroy_wq);
1121 	cw->ctx->flushing = 0;
1122 	kfree(cw);
1123 }
1124 
1125 void mlx4_ib_mcg_port_cleanup(struct mlx4_ib_demux_ctx *ctx, int destroy_wq)
1126 {
1127 	struct clean_work *work;
1128 
1129 	if (ctx->flushing)
1130 		return;
1131 
1132 	ctx->flushing = 1;
1133 
1134 	if (destroy_wq) {
1135 		_mlx4_ib_mcg_port_cleanup(ctx, destroy_wq);
1136 		ctx->flushing = 0;
1137 		return;
1138 	}
1139 
1140 	work = kmalloc(sizeof *work, GFP_KERNEL);
1141 	if (!work) {
1142 		ctx->flushing = 0;
1143 		mcg_warn("failed allocating work for cleanup\n");
1144 		return;
1145 	}
1146 
1147 	work->ctx = ctx;
1148 	work->destroy_wq = destroy_wq;
1149 	INIT_WORK(&work->work, mcg_clean_task);
1150 	queue_work(clean_wq, &work->work);
1151 }
1152 
1153 static void build_leave_mad(struct mcast_req *req)
1154 {
1155 	struct ib_sa_mad *mad = &req->sa_mad;
1156 
1157 	mad->mad_hdr.method = IB_SA_METHOD_DELETE;
1158 }
1159 
1160 
1161 static void clear_pending_reqs(struct mcast_group *group, int vf)
1162 {
1163 	struct mcast_req *req, *tmp, *group_first = NULL;
1164 	int clear;
1165 	int pend = 0;
1166 
1167 	if (!list_empty(&group->pending_list))
1168 		group_first = list_first_entry(&group->pending_list, struct mcast_req, group_list);
1169 
1170 	list_for_each_entry_safe(req, tmp, &group->func[vf].pending, func_list) {
1171 		clear = 1;
1172 		if (group_first == req &&
1173 		    (group->state == MCAST_JOIN_SENT ||
1174 		     group->state == MCAST_LEAVE_SENT)) {
1175 			clear = cancel_delayed_work(&group->timeout_work);
1176 			pend = !clear;
1177 			group->state = MCAST_IDLE;
1178 		}
1179 		if (clear) {
1180 			--group->func[vf].num_pend_reqs;
1181 			list_del(&req->group_list);
1182 			list_del(&req->func_list);
1183 			kfree(req);
1184 			atomic_dec(&group->refcount);
1185 		}
1186 	}
1187 
1188 	if (!pend && (!list_empty(&group->func[vf].pending) || group->func[vf].num_pend_reqs)) {
1189 		mcg_warn_group(group, "DRIVER BUG: list_empty %d, num_pend_reqs %d\n",
1190 			       list_empty(&group->func[vf].pending), group->func[vf].num_pend_reqs);
1191 	}
1192 }
1193 
1194 static int push_deleteing_req(struct mcast_group *group, int slave)
1195 {
1196 	struct mcast_req *req;
1197 	struct mcast_req *pend_req;
1198 
1199 	if (!group->func[slave].join_state)
1200 		return 0;
1201 
1202 	req = kzalloc(sizeof *req, GFP_KERNEL);
1203 	if (!req) {
1204 		mcg_warn_group(group, "failed allocation - may leave stall groups\n");
1205 		return -ENOMEM;
1206 	}
1207 
1208 	if (!list_empty(&group->func[slave].pending)) {
1209 		pend_req = list_entry(group->func[slave].pending.prev, struct mcast_req, group_list);
1210 		if (pend_req->clean) {
1211 			kfree(req);
1212 			return 0;
1213 		}
1214 	}
1215 
1216 	req->clean = 1;
1217 	req->func = slave;
1218 	req->group = group;
1219 	++group->func[slave].num_pend_reqs;
1220 	build_leave_mad(req);
1221 	queue_req(req);
1222 	return 0;
1223 }
1224 
1225 void clean_vf_mcast(struct mlx4_ib_demux_ctx *ctx, int slave)
1226 {
1227 	struct mcast_group *group;
1228 	struct rb_node *p;
1229 
1230 	mutex_lock(&ctx->mcg_table_lock);
1231 	for (p = rb_first(&ctx->mcg_table); p; p = rb_next(p)) {
1232 		group = rb_entry(p, struct mcast_group, node);
1233 		mutex_lock(&group->lock);
1234 		if (atomic_read(&group->refcount)) {
1235 			/* clear pending requests of this VF */
1236 			clear_pending_reqs(group, slave);
1237 			push_deleteing_req(group, slave);
1238 		}
1239 		mutex_unlock(&group->lock);
1240 	}
1241 	mutex_unlock(&ctx->mcg_table_lock);
1242 }
1243 
1244 
1245 int mlx4_ib_mcg_init(void)
1246 {
1247 	clean_wq = create_singlethread_workqueue("mlx4_ib_mcg");
1248 	if (!clean_wq)
1249 		return -ENOMEM;
1250 
1251 	return 0;
1252 }
1253 
1254 void mlx4_ib_mcg_destroy(void)
1255 {
1256 	destroy_workqueue(clean_wq);
1257 }
1258