xref: /linux/net/smc/smc_ism.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Shared Memory Communications Direct over ISM devices (SMC-D)
3  *
4  * Functions for ISM device.
5  *
6  * Copyright IBM Corp. 2018
7  */
8 
9 #include <linux/if_vlan.h>
10 #include <linux/spinlock.h>
11 #include <linux/mutex.h>
12 #include <linux/slab.h>
13 #include <asm/page.h>
14 
15 #include "smc.h"
16 #include "smc_core.h"
17 #include "smc_ism.h"
18 #include "smc_pnet.h"
19 #include "smc_netlink.h"
20 #include "linux/dibs.h"
21 
22 struct smcd_dev_list smcd_dev_list = {
23 	.list = LIST_HEAD_INIT(smcd_dev_list.list),
24 	.mutex = __MUTEX_INITIALIZER(smcd_dev_list.mutex)
25 };
26 
27 static bool smc_ism_v2_capable;
28 static u8 smc_ism_v2_system_eid[SMC_MAX_EID_LEN];
29 
30 static void smcd_register_dev(struct dibs_dev *dibs);
31 static void smcd_unregister_dev(struct dibs_dev *dibs);
32 static void smcd_handle_event(struct dibs_dev *dibs,
33 			      const struct dibs_event *event);
34 static void smcd_handle_irq(struct dibs_dev *dibs, unsigned int dmbno,
35 			    u16 dmbemask);
36 
37 static struct dibs_client_ops smc_client_ops = {
38 	.add_dev = smcd_register_dev,
39 	.del_dev = smcd_unregister_dev,
40 	.handle_event = smcd_handle_event,
41 	.handle_irq = smcd_handle_irq,
42 };
43 
44 static struct dibs_client smc_dibs_client = {
45 	.name = "SMC-D",
46 	.ops = &smc_client_ops,
47 };
48 
49 static void smc_ism_create_system_eid(void)
50 {
51 	struct smc_ism_seid *seid =
52 		(struct smc_ism_seid *)smc_ism_v2_system_eid;
53 #if IS_ENABLED(CONFIG_S390)
54 	struct cpuid id;
55 	u16 ident_tail;
56 	char tmp[5];
57 
58 	memcpy(seid->seid_string, "IBM-SYSZ-ISMSEID00000000", 24);
59 	get_cpu_id(&id);
60 	ident_tail = (u16)(id.ident & SMC_ISM_IDENT_MASK);
61 	snprintf(tmp, 5, "%04X", ident_tail);
62 	memcpy(seid->serial_number, tmp, 4);
63 	snprintf(tmp, 5, "%04X", id.machine);
64 	memcpy(seid->type, tmp, 4);
65 #else
66 	memset(seid, 0, SMC_MAX_EID_LEN);
67 #endif
68 }
69 
70 /* Test if an ISM communication is possible - same CPC */
71 int smc_ism_cantalk(struct smcd_gid *peer_gid, unsigned short vlan_id,
72 		    struct smcd_dev *smcd)
73 {
74 	struct dibs_dev *dibs = smcd->dibs;
75 	uuid_t ism_rgid;
76 
77 	copy_to_dibsgid(&ism_rgid, peer_gid);
78 	return dibs->ops->query_remote_gid(dibs, &ism_rgid, vlan_id ? 1 : 0,
79 					  vlan_id);
80 }
81 
82 void smc_ism_get_system_eid(u8 **eid)
83 {
84 	if (!smc_ism_v2_capable)
85 		*eid = NULL;
86 	else
87 		*eid = smc_ism_v2_system_eid;
88 }
89 
90 u16 smc_ism_get_chid(struct smcd_dev *smcd)
91 {
92 	return smcd->dibs->ops->get_fabric_id(smcd->dibs);
93 }
94 
95 /* HW supports ISM V2 and thus System EID is defined */
96 bool smc_ism_is_v2_capable(void)
97 {
98 	return smc_ism_v2_capable;
99 }
100 
101 void smc_ism_set_v2_capable(void)
102 {
103 	smc_ism_v2_capable = true;
104 }
105 
106 /* Set a connection using this DMBE. */
107 void smc_ism_set_conn(struct smc_connection *conn)
108 {
109 	unsigned long flags;
110 
111 	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
112 	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = conn;
113 	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
114 }
115 
116 /* Unset a connection using this DMBE. */
117 void smc_ism_unset_conn(struct smc_connection *conn)
118 {
119 	unsigned long flags;
120 
121 	if (!conn->rmb_desc)
122 		return;
123 
124 	spin_lock_irqsave(&conn->lgr->smcd->lock, flags);
125 	conn->lgr->smcd->conn[conn->rmb_desc->sba_idx] = NULL;
126 	spin_unlock_irqrestore(&conn->lgr->smcd->lock, flags);
127 }
128 
129 /* Register a VLAN identifier with the ISM device. Use a reference count
130  * and add a VLAN identifier only when the first DMB using this VLAN is
131  * registered.
132  */
133 int smc_ism_get_vlan(struct smcd_dev *smcd, unsigned short vlanid)
134 {
135 	struct smc_ism_vlanid *new_vlan, *vlan;
136 	unsigned long flags;
137 	int rc = 0;
138 
139 	if (!vlanid)			/* No valid vlan id */
140 		return -EINVAL;
141 	if (!smcd->dibs->ops->add_vlan_id)
142 		return -EOPNOTSUPP;
143 
144 	/* create new vlan entry, in case we need it */
145 	new_vlan = kzalloc(sizeof(*new_vlan), GFP_KERNEL);
146 	if (!new_vlan)
147 		return -ENOMEM;
148 	new_vlan->vlanid = vlanid;
149 	refcount_set(&new_vlan->refcnt, 1);
150 
151 	/* if there is an existing entry, increase count and return */
152 	spin_lock_irqsave(&smcd->lock, flags);
153 	list_for_each_entry(vlan, &smcd->vlan, list) {
154 		if (vlan->vlanid == vlanid) {
155 			refcount_inc(&vlan->refcnt);
156 			kfree(new_vlan);
157 			goto out;
158 		}
159 	}
160 
161 	/* no existing entry found.
162 	 * add new entry to device; might fail, e.g., if HW limit reached
163 	 */
164 	if (smcd->dibs->ops->add_vlan_id(smcd->dibs, vlanid)) {
165 		kfree(new_vlan);
166 		rc = -EIO;
167 		goto out;
168 	}
169 	list_add_tail(&new_vlan->list, &smcd->vlan);
170 out:
171 	spin_unlock_irqrestore(&smcd->lock, flags);
172 	return rc;
173 }
174 
175 /* Unregister a VLAN identifier with the ISM device. Use a reference count
176  * and remove a VLAN identifier only when the last DMB using this VLAN is
177  * unregistered.
178  */
179 int smc_ism_put_vlan(struct smcd_dev *smcd, unsigned short vlanid)
180 {
181 	struct smc_ism_vlanid *vlan;
182 	unsigned long flags;
183 	bool found = false;
184 	int rc = 0;
185 
186 	if (!vlanid)			/* No valid vlan id */
187 		return -EINVAL;
188 	if (!smcd->dibs->ops->del_vlan_id)
189 		return -EOPNOTSUPP;
190 
191 	spin_lock_irqsave(&smcd->lock, flags);
192 	list_for_each_entry(vlan, &smcd->vlan, list) {
193 		if (vlan->vlanid == vlanid) {
194 			if (!refcount_dec_and_test(&vlan->refcnt))
195 				goto out;
196 			found = true;
197 			break;
198 		}
199 	}
200 	if (!found) {
201 		rc = -ENOENT;
202 		goto out;		/* VLAN id not in table */
203 	}
204 
205 	/* Found and the last reference just gone */
206 	if (smcd->dibs->ops->del_vlan_id(smcd->dibs, vlanid))
207 		rc = -EIO;
208 	list_del(&vlan->list);
209 	kfree(vlan);
210 out:
211 	spin_unlock_irqrestore(&smcd->lock, flags);
212 	return rc;
213 }
214 
215 void smc_ism_unregister_dmb(struct smcd_dev *smcd,
216 			    struct smc_buf_desc *dmb_desc)
217 {
218 	struct dibs_dmb dmb;
219 
220 	if (!dmb_desc->dma_addr)
221 		return;
222 
223 	memset(&dmb, 0, sizeof(dmb));
224 	dmb.dmb_tok = dmb_desc->token;
225 	dmb.idx = dmb_desc->sba_idx;
226 	dmb.cpu_addr = dmb_desc->cpu_addr;
227 	dmb.dma_addr = dmb_desc->dma_addr;
228 	dmb.dmb_len = dmb_desc->len;
229 
230 	smcd->dibs->ops->unregister_dmb(smcd->dibs, &dmb);
231 
232 	return;
233 }
234 
235 int smc_ism_register_dmb(struct smc_link_group *lgr, int dmb_len,
236 			 struct smc_buf_desc *dmb_desc)
237 {
238 	struct dibs_dev *dibs;
239 	struct dibs_dmb dmb;
240 	int rc;
241 
242 	memset(&dmb, 0, sizeof(dmb));
243 	dmb.dmb_len = dmb_len;
244 	dmb.idx = dmb_desc->sba_idx;
245 	dmb.vlan_id = lgr->vlan_id;
246 	copy_to_dibsgid(&dmb.rgid, &lgr->peer_gid);
247 
248 	dibs = lgr->smcd->dibs;
249 	rc = dibs->ops->register_dmb(dibs, &dmb, &smc_dibs_client);
250 	if (!rc) {
251 		dmb_desc->sba_idx = dmb.idx;
252 		dmb_desc->token = dmb.dmb_tok;
253 		dmb_desc->cpu_addr = dmb.cpu_addr;
254 		dmb_desc->dma_addr = dmb.dma_addr;
255 		dmb_desc->len = dmb.dmb_len;
256 	}
257 	return rc;
258 }
259 
260 bool smc_ism_support_dmb_nocopy(struct smcd_dev *smcd)
261 {
262 	/* for now only loopback-ism supports
263 	 * merging sndbuf with peer DMB to avoid
264 	 * data copies between them.
265 	 */
266 	return (smcd->dibs->ops->support_mmapped_rdmb &&
267 		smcd->dibs->ops->support_mmapped_rdmb(smcd->dibs));
268 }
269 
270 int smc_ism_attach_dmb(struct smcd_dev *dev, u64 token,
271 		       struct smc_buf_desc *dmb_desc)
272 {
273 	struct dibs_dmb dmb;
274 	int rc = 0;
275 
276 	if (!dev->dibs->ops->attach_dmb)
277 		return -EINVAL;
278 
279 	memset(&dmb, 0, sizeof(dmb));
280 	dmb.dmb_tok = token;
281 	rc = dev->dibs->ops->attach_dmb(dev->dibs, &dmb);
282 	if (!rc) {
283 		dmb_desc->sba_idx = dmb.idx;
284 		dmb_desc->token = dmb.dmb_tok;
285 		dmb_desc->cpu_addr = dmb.cpu_addr;
286 		dmb_desc->dma_addr = dmb.dma_addr;
287 		dmb_desc->len = dmb.dmb_len;
288 		dmb_desc->is_attached = true;
289 	}
290 	return rc;
291 }
292 
293 int smc_ism_detach_dmb(struct smcd_dev *dev, u64 token)
294 {
295 	if (!dev->dibs->ops->detach_dmb)
296 		return -EINVAL;
297 
298 	return dev->dibs->ops->detach_dmb(dev->dibs, token);
299 }
300 
301 static int smc_nl_handle_smcd_dev(struct smcd_dev *smcd,
302 				  struct sk_buff *skb,
303 				  struct netlink_callback *cb)
304 {
305 	char smc_pnet[SMC_MAX_PNETID_LEN + 1];
306 	struct smc_pci_dev smc_pci_dev;
307 	struct nlattr *port_attrs;
308 	struct dibs_dev *dibs;
309 	struct nlattr *attrs;
310 	int use_cnt = 0;
311 	void *nlh;
312 
313 	dibs = smcd->dibs;
314 	nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
315 			  &smc_gen_nl_family, NLM_F_MULTI,
316 			  SMC_NETLINK_GET_DEV_SMCD);
317 	if (!nlh)
318 		goto errmsg;
319 	attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCD);
320 	if (!attrs)
321 		goto errout;
322 	use_cnt = atomic_read(&smcd->lgr_cnt);
323 	if (nla_put_u32(skb, SMC_NLA_DEV_USE_CNT, use_cnt))
324 		goto errattr;
325 	if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, use_cnt > 0))
326 		goto errattr;
327 	memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
328 	smc_set_pci_values(to_pci_dev(dibs->dev.parent), &smc_pci_dev);
329 	if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev.pci_fid))
330 		goto errattr;
331 	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev.pci_pchid))
332 		goto errattr;
333 	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev.pci_vendor))
334 		goto errattr;
335 	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev.pci_device))
336 		goto errattr;
337 	if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev.pci_id))
338 		goto errattr;
339 
340 	port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT);
341 	if (!port_attrs)
342 		goto errattr;
343 	if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR, smcd->pnetid_by_user))
344 		goto errportattr;
345 	memcpy(smc_pnet, smcd->pnetid, SMC_MAX_PNETID_LEN);
346 	smc_pnet[SMC_MAX_PNETID_LEN] = 0;
347 	if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
348 		goto errportattr;
349 
350 	nla_nest_end(skb, port_attrs);
351 	nla_nest_end(skb, attrs);
352 	genlmsg_end(skb, nlh);
353 	return 0;
354 
355 errportattr:
356 	nla_nest_cancel(skb, port_attrs);
357 errattr:
358 	nla_nest_cancel(skb, attrs);
359 errout:
360 	nlmsg_cancel(skb, nlh);
361 errmsg:
362 	return -EMSGSIZE;
363 }
364 
365 static void smc_nl_prep_smcd_dev(struct smcd_dev_list *dev_list,
366 				 struct sk_buff *skb,
367 				 struct netlink_callback *cb)
368 {
369 	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
370 	int snum = cb_ctx->pos[0];
371 	struct smcd_dev *smcd;
372 	int num = 0;
373 
374 	mutex_lock(&dev_list->mutex);
375 	list_for_each_entry(smcd, &dev_list->list, list) {
376 		if (num < snum)
377 			goto next;
378 		if (smc_ism_is_loopback(smcd->dibs))
379 			goto next;
380 		if (smc_nl_handle_smcd_dev(smcd, skb, cb))
381 			goto errout;
382 next:
383 		num++;
384 	}
385 errout:
386 	mutex_unlock(&dev_list->mutex);
387 	cb_ctx->pos[0] = num;
388 }
389 
390 int smcd_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
391 {
392 	smc_nl_prep_smcd_dev(&smcd_dev_list, skb, cb);
393 	return skb->len;
394 }
395 
396 struct smc_ism_event_work {
397 	struct work_struct work;
398 	struct smcd_dev *smcd;
399 	struct dibs_event event;
400 };
401 
402 #define ISM_EVENT_REQUEST		0x0001
403 #define ISM_EVENT_RESPONSE		0x0002
404 #define ISM_EVENT_REQUEST_IR		0x00000001
405 #define ISM_EVENT_CODE_SHUTDOWN		0x80
406 #define ISM_EVENT_CODE_TESTLINK		0x83
407 
408 union smcd_sw_event_info {
409 	u64	info;
410 	struct {
411 		u8		uid[SMC_LGR_ID_SIZE];
412 		unsigned short	vlan_id;
413 		u16		code;
414 	};
415 };
416 
417 static void smcd_handle_sw_event(struct smc_ism_event_work *wrk)
418 {
419 	struct dibs_dev *dibs = wrk->smcd->dibs;
420 	union smcd_sw_event_info ev_info;
421 	struct smcd_gid peer_gid;
422 	uuid_t ism_rgid;
423 
424 	copy_to_smcdgid(&peer_gid, &wrk->event.gid);
425 	ev_info.info = wrk->event.data;
426 	switch (wrk->event.subtype) {
427 	case ISM_EVENT_CODE_SHUTDOWN:	/* Peer shut down DMBs */
428 		smc_smcd_terminate(wrk->smcd, &peer_gid, ev_info.vlan_id);
429 		break;
430 	case ISM_EVENT_CODE_TESTLINK:	/* Activity timer */
431 		if (ev_info.code == ISM_EVENT_REQUEST &&
432 		    dibs->ops->signal_event) {
433 			ev_info.code = ISM_EVENT_RESPONSE;
434 			copy_to_dibsgid(&ism_rgid, &peer_gid);
435 			dibs->ops->signal_event(dibs, &ism_rgid,
436 					       ISM_EVENT_REQUEST_IR,
437 					       ISM_EVENT_CODE_TESTLINK,
438 					       ev_info.info);
439 		}
440 		break;
441 	}
442 }
443 
444 /* worker for SMC-D events */
445 static void smc_ism_event_work(struct work_struct *work)
446 {
447 	struct smc_ism_event_work *wrk =
448 		container_of(work, struct smc_ism_event_work, work);
449 	struct smcd_gid smcd_gid;
450 
451 	copy_to_smcdgid(&smcd_gid, &wrk->event.gid);
452 
453 	switch (wrk->event.type) {
454 	case DIBS_DEV_EVENT: /* GID event, token is peer GID */
455 		smc_smcd_terminate(wrk->smcd, &smcd_gid, VLAN_VID_MASK);
456 		break;
457 	case DIBS_BUF_EVENT:
458 		break;
459 	case DIBS_SW_EVENT: /* Software defined event */
460 		smcd_handle_sw_event(wrk);
461 		break;
462 	}
463 	kfree(wrk);
464 }
465 
466 static struct smcd_dev *smcd_alloc_dev(const char *name, int max_dmbs)
467 {
468 	struct smcd_dev *smcd;
469 
470 	smcd = kzalloc(sizeof(*smcd), GFP_KERNEL);
471 	if (!smcd)
472 		return NULL;
473 	smcd->conn = kcalloc(max_dmbs, sizeof(struct smc_connection *),
474 			     GFP_KERNEL);
475 	if (!smcd->conn)
476 		goto free_smcd;
477 
478 	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
479 						 WQ_MEM_RECLAIM, name);
480 	if (!smcd->event_wq)
481 		goto free_conn;
482 
483 	spin_lock_init(&smcd->lock);
484 	spin_lock_init(&smcd->lgr_lock);
485 	INIT_LIST_HEAD(&smcd->vlan);
486 	INIT_LIST_HEAD(&smcd->lgr_list);
487 	init_waitqueue_head(&smcd->lgrs_deleted);
488 	return smcd;
489 
490 free_conn:
491 	kfree(smcd->conn);
492 free_smcd:
493 	kfree(smcd);
494 	return NULL;
495 }
496 
497 static void smcd_register_dev(struct dibs_dev *dibs)
498 {
499 	struct smcd_dev *smcd, *fentry;
500 	int max_dmbs;
501 
502 	max_dmbs = dibs->ops->max_dmbs();
503 
504 	smcd = smcd_alloc_dev(dev_name(&dibs->dev), max_dmbs);
505 	if (!smcd)
506 		return;
507 
508 	smcd->dibs = dibs;
509 	dibs_set_priv(dibs, &smc_dibs_client, smcd);
510 
511 	if (smc_pnetid_by_dev_port(dibs->dev.parent, 0, smcd->pnetid))
512 		smc_pnetid_by_table_smcd(smcd);
513 
514 	if (smc_ism_is_loopback(dibs) ||
515 	    (dibs->ops->add_vlan_id &&
516 	     !dibs->ops->add_vlan_id(dibs, ISM_RESERVED_VLANID))) {
517 		smc_ism_set_v2_capable();
518 	}
519 
520 	mutex_lock(&smcd_dev_list.mutex);
521 	/* sort list:
522 	 * - devices without pnetid before devices with pnetid;
523 	 * - loopback-ism always at the very beginning;
524 	 */
525 	if (!smcd->pnetid[0]) {
526 		fentry = list_first_entry_or_null(&smcd_dev_list.list,
527 						  struct smcd_dev, list);
528 		if (fentry && smc_ism_is_loopback(fentry->dibs))
529 			list_add(&smcd->list, &fentry->list);
530 		else
531 			list_add(&smcd->list, &smcd_dev_list.list);
532 	} else {
533 		list_add_tail(&smcd->list, &smcd_dev_list.list);
534 	}
535 	mutex_unlock(&smcd_dev_list.mutex);
536 
537 	if (smc_pnet_is_pnetid_set(smcd->pnetid))
538 		pr_warn_ratelimited("smc: adding smcd device %s with pnetid %.16s%s\n",
539 				    dev_name(&dibs->dev), smcd->pnetid,
540 				    smcd->pnetid_by_user ?
541 					" (user defined)" :
542 					"");
543 	else
544 		pr_warn_ratelimited("smc: adding smcd device %s without pnetid\n",
545 				    dev_name(&dibs->dev));
546 	return;
547 }
548 
549 static void smcd_unregister_dev(struct dibs_dev *dibs)
550 {
551 	struct smcd_dev *smcd = dibs_get_priv(dibs, &smc_dibs_client);
552 
553 	pr_warn_ratelimited("smc: removing smcd device %s\n",
554 			    dev_name(&dibs->dev));
555 	smcd->going_away = 1;
556 	smc_smcd_terminate_all(smcd);
557 	mutex_lock(&smcd_dev_list.mutex);
558 	list_del_init(&smcd->list);
559 	mutex_unlock(&smcd_dev_list.mutex);
560 	destroy_workqueue(smcd->event_wq);
561 	kfree(smcd->conn);
562 	kfree(smcd);
563 }
564 
565 /* SMCD Device event handler. Called from ISM device interrupt handler.
566  * Parameters are ism device pointer,
567  * - event->type (0 --> DMB, 1 --> GID),
568  * - event->code (event code),
569  * - event->tok (either DMB token when event type 0, or GID when event type 1)
570  * - event->time (time of day)
571  * - event->info (debug info).
572  *
573  * Context:
574  * - Function called in IRQ context from ISM device driver event handler.
575  */
576 static void smcd_handle_event(struct dibs_dev *dibs,
577 			      const struct dibs_event *event)
578 {
579 	struct smcd_dev *smcd = dibs_get_priv(dibs, &smc_dibs_client);
580 	struct smc_ism_event_work *wrk;
581 
582 	if (smcd->going_away)
583 		return;
584 	/* copy event to event work queue, and let it be handled there */
585 	wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC);
586 	if (!wrk)
587 		return;
588 	INIT_WORK(&wrk->work, smc_ism_event_work);
589 	wrk->smcd = smcd;
590 	wrk->event = *event;
591 	queue_work(smcd->event_wq, &wrk->work);
592 }
593 
594 /* SMCD Device interrupt handler. Called from ISM device interrupt handler.
595  * Parameters are the ism device pointer, DMB number, and the DMBE bitmask.
596  * Find the connection and schedule the tasklet for this connection.
597  *
598  * Context:
599  * - Function called in IRQ context from ISM device driver IRQ handler.
600  */
601 static void smcd_handle_irq(struct dibs_dev *dibs, unsigned int dmbno,
602 			    u16 dmbemask)
603 {
604 	struct smcd_dev *smcd = dibs_get_priv(dibs, &smc_dibs_client);
605 	struct smc_connection *conn = NULL;
606 	unsigned long flags;
607 
608 	spin_lock_irqsave(&smcd->lock, flags);
609 	conn = smcd->conn[dmbno];
610 	if (conn && !conn->killed)
611 		tasklet_schedule(&conn->rx_tsklet);
612 	spin_unlock_irqrestore(&smcd->lock, flags);
613 }
614 
615 int smc_ism_signal_shutdown(struct smc_link_group *lgr)
616 {
617 	int rc = 0;
618 	union smcd_sw_event_info ev_info;
619 	uuid_t ism_rgid;
620 
621 	if (lgr->peer_shutdown)
622 		return 0;
623 	if (!lgr->smcd->dibs->ops->signal_event)
624 		return 0;
625 
626 	memcpy(ev_info.uid, lgr->id, SMC_LGR_ID_SIZE);
627 	ev_info.vlan_id = lgr->vlan_id;
628 	ev_info.code = ISM_EVENT_REQUEST;
629 	copy_to_dibsgid(&ism_rgid, &lgr->peer_gid);
630 	rc = lgr->smcd->dibs->ops->signal_event(lgr->smcd->dibs, &ism_rgid,
631 					  ISM_EVENT_REQUEST_IR,
632 					  ISM_EVENT_CODE_SHUTDOWN,
633 					  ev_info.info);
634 	return rc;
635 }
636 
637 int smc_ism_init(void)
638 {
639 	int rc = 0;
640 
641 	smc_ism_v2_capable = false;
642 	smc_ism_create_system_eid();
643 
644 	rc = dibs_register_client(&smc_dibs_client);
645 	return rc;
646 }
647 
648 void smc_ism_exit(void)
649 {
650 	dibs_unregister_client(&smc_dibs_client);
651 }
652