1 // SPDX-License-Identifier: GPL-2.0 or BSD-3-Clause
2 
3 /* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
4 /* Copyright (c) 2008-2019, IBM Corporation */
5 
6 #include <linux/init.h>
7 #include <linux/errno.h>
8 #include <linux/netdevice.h>
9 #include <linux/inetdevice.h>
10 #include <net/net_namespace.h>
11 #include <linux/rtnetlink.h>
12 #include <linux/if_arp.h>
13 #include <linux/list.h>
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/module.h>
17 #include <linux/dma-mapping.h>
18 
19 #include <rdma/ib_verbs.h>
20 #include <rdma/ib_user_verbs.h>
21 #include <rdma/rdma_netlink.h>
22 #include <linux/kthread.h>
23 
24 #include "siw.h"
25 #include "siw_verbs.h"
26 
27 MODULE_AUTHOR("Bernard Metzler");
28 MODULE_DESCRIPTION("Software iWARP Driver");
29 MODULE_LICENSE("Dual BSD/GPL");
30 
31 /* transmit from user buffer, if possible */
32 const bool zcopy_tx = true;
33 
34 /* Restrict usage of GSO, if hardware peer iwarp is unable to process
35  * large packets. try_gso = true lets siw try to use local GSO,
36  * if peer agrees.  Not using GSO severly limits siw maximum tx bandwidth.
37  */
38 const bool try_gso;
39 
40 /* Attach siw also with loopback devices */
41 const bool loopback_enabled = true;
42 
43 /* We try to negotiate CRC on, if true */
44 const bool mpa_crc_required;
45 
46 /* MPA CRC on/off enforced */
47 const bool mpa_crc_strict;
48 
49 /* Control TCP_NODELAY socket option */
50 const bool siw_tcp_nagle;
51 
52 /* Select MPA version to be used during connection setup */
53 u_char mpa_version = MPA_REVISION_2;
54 
55 /* Selects MPA P2P mode (additional handshake during connection
56  * setup, if true.
57  */
58 const bool peer_to_peer;
59 
60 struct task_struct *siw_tx_thread[NR_CPUS];
61 struct crypto_shash *siw_crypto_shash;
62 
63 static int siw_device_register(struct siw_device *sdev, const char *name)
64 {
65 	struct ib_device *base_dev = &sdev->base_dev;
66 	static int dev_id = 1;
67 	int rv;
68 
69 	rv = ib_register_device(base_dev, name);
70 	if (rv) {
71 		pr_warn("siw: device registration error %d\n", rv);
72 		return rv;
73 	}
74 	sdev->vendor_part_id = dev_id++;
75 
76 	siw_dbg(base_dev, "HWaddr=%pM\n", sdev->netdev->dev_addr);
77 
78 	return 0;
79 }
80 
81 static void siw_device_cleanup(struct ib_device *base_dev)
82 {
83 	struct siw_device *sdev = to_siw_dev(base_dev);
84 
85 	xa_destroy(&sdev->qp_xa);
86 	xa_destroy(&sdev->mem_xa);
87 }
88 
89 static int siw_create_tx_threads(void)
90 {
91 	int cpu, assigned = 0;
92 
93 	for_each_online_cpu(cpu) {
94 		/* Skip HT cores */
95 		if (cpu % cpumask_weight(topology_sibling_cpumask(cpu)))
96 			continue;
97 
98 		siw_tx_thread[cpu] =
99 			kthread_create(siw_run_sq, (unsigned long *)(long)cpu,
100 				       "siw_tx/%d", cpu);
101 		if (IS_ERR(siw_tx_thread[cpu])) {
102 			siw_tx_thread[cpu] = NULL;
103 			continue;
104 		}
105 		kthread_bind(siw_tx_thread[cpu], cpu);
106 
107 		wake_up_process(siw_tx_thread[cpu]);
108 		assigned++;
109 	}
110 	return assigned;
111 }
112 
113 static int siw_dev_qualified(struct net_device *netdev)
114 {
115 	/*
116 	 * Additional hardware support can be added here
117 	 * (e.g. ARPHRD_FDDI, ARPHRD_ATM, ...) - see
118 	 * <linux/if_arp.h> for type identifiers.
119 	 */
120 	if (netdev->type == ARPHRD_ETHER || netdev->type == ARPHRD_IEEE802 ||
121 	    (netdev->type == ARPHRD_LOOPBACK && loopback_enabled))
122 		return 1;
123 
124 	return 0;
125 }
126 
127 static DEFINE_PER_CPU(atomic_t, siw_use_cnt);
128 
129 static struct {
130 	struct cpumask **tx_valid_cpus;
131 	int num_nodes;
132 } siw_cpu_info;
133 
134 static int siw_init_cpulist(void)
135 {
136 	int i, num_nodes = num_possible_nodes();
137 
138 	memset(siw_tx_thread, 0, sizeof(siw_tx_thread));
139 
140 	siw_cpu_info.num_nodes = num_nodes;
141 
142 	siw_cpu_info.tx_valid_cpus =
143 		kcalloc(num_nodes, sizeof(struct cpumask *), GFP_KERNEL);
144 	if (!siw_cpu_info.tx_valid_cpus) {
145 		siw_cpu_info.num_nodes = 0;
146 		return -ENOMEM;
147 	}
148 	for (i = 0; i < siw_cpu_info.num_nodes; i++) {
149 		siw_cpu_info.tx_valid_cpus[i] =
150 			kzalloc(sizeof(struct cpumask), GFP_KERNEL);
151 		if (!siw_cpu_info.tx_valid_cpus[i])
152 			goto out_err;
153 
154 		cpumask_clear(siw_cpu_info.tx_valid_cpus[i]);
155 	}
156 	for_each_possible_cpu(i)
157 		cpumask_set_cpu(i, siw_cpu_info.tx_valid_cpus[cpu_to_node(i)]);
158 
159 	return 0;
160 
161 out_err:
162 	siw_cpu_info.num_nodes = 0;
163 	while (--i >= 0)
164 		kfree(siw_cpu_info.tx_valid_cpus[i]);
165 	kfree(siw_cpu_info.tx_valid_cpus);
166 	siw_cpu_info.tx_valid_cpus = NULL;
167 
168 	return -ENOMEM;
169 }
170 
171 static void siw_destroy_cpulist(void)
172 {
173 	int i = 0;
174 
175 	while (i < siw_cpu_info.num_nodes)
176 		kfree(siw_cpu_info.tx_valid_cpus[i++]);
177 
178 	kfree(siw_cpu_info.tx_valid_cpus);
179 }
180 
181 /*
182  * Choose CPU with least number of active QP's from NUMA node of
183  * TX interface.
184  */
185 int siw_get_tx_cpu(struct siw_device *sdev)
186 {
187 	const struct cpumask *tx_cpumask;
188 	int i, num_cpus, cpu, min_use, node = sdev->numa_node, tx_cpu = -1;
189 
190 	if (node < 0)
191 		tx_cpumask = cpu_online_mask;
192 	else
193 		tx_cpumask = siw_cpu_info.tx_valid_cpus[node];
194 
195 	num_cpus = cpumask_weight(tx_cpumask);
196 	if (!num_cpus) {
197 		/* no CPU on this NUMA node */
198 		tx_cpumask = cpu_online_mask;
199 		num_cpus = cpumask_weight(tx_cpumask);
200 	}
201 	if (!num_cpus)
202 		goto out;
203 
204 	cpu = cpumask_first(tx_cpumask);
205 
206 	for (i = 0, min_use = SIW_MAX_QP; i < num_cpus;
207 	     i++, cpu = cpumask_next(cpu, tx_cpumask)) {
208 		int usage;
209 
210 		/* Skip any cores which have no TX thread */
211 		if (!siw_tx_thread[cpu])
212 			continue;
213 
214 		usage = atomic_read(&per_cpu(siw_use_cnt, cpu));
215 		if (usage <= min_use) {
216 			tx_cpu = cpu;
217 			min_use = usage;
218 		}
219 	}
220 	siw_dbg(&sdev->base_dev,
221 		"tx cpu %d, node %d, %d qp's\n", tx_cpu, node, min_use);
222 
223 out:
224 	if (tx_cpu >= 0)
225 		atomic_inc(&per_cpu(siw_use_cnt, tx_cpu));
226 	else
227 		pr_warn("siw: no tx cpu found\n");
228 
229 	return tx_cpu;
230 }
231 
232 void siw_put_tx_cpu(int cpu)
233 {
234 	atomic_dec(&per_cpu(siw_use_cnt, cpu));
235 }
236 
237 static struct ib_qp *siw_get_base_qp(struct ib_device *base_dev, int id)
238 {
239 	struct siw_qp *qp = siw_qp_id2obj(to_siw_dev(base_dev), id);
240 
241 	if (qp) {
242 		/*
243 		 * siw_qp_id2obj() increments object reference count
244 		 */
245 		siw_qp_put(qp);
246 		return qp->ib_qp;
247 	}
248 	return NULL;
249 }
250 
251 static void siw_verbs_sq_flush(struct ib_qp *base_qp)
252 {
253 	struct siw_qp *qp = to_siw_qp(base_qp);
254 
255 	down_write(&qp->state_lock);
256 	siw_sq_flush(qp);
257 	up_write(&qp->state_lock);
258 }
259 
260 static void siw_verbs_rq_flush(struct ib_qp *base_qp)
261 {
262 	struct siw_qp *qp = to_siw_qp(base_qp);
263 
264 	down_write(&qp->state_lock);
265 	siw_rq_flush(qp);
266 	up_write(&qp->state_lock);
267 }
268 
269 static const struct ib_device_ops siw_device_ops = {
270 	.owner = THIS_MODULE,
271 	.uverbs_abi_ver = SIW_ABI_VERSION,
272 	.driver_id = RDMA_DRIVER_SIW,
273 
274 	.alloc_mr = siw_alloc_mr,
275 	.alloc_pd = siw_alloc_pd,
276 	.alloc_ucontext = siw_alloc_ucontext,
277 	.create_cq = siw_create_cq,
278 	.create_qp = siw_create_qp,
279 	.create_srq = siw_create_srq,
280 	.dealloc_driver = siw_device_cleanup,
281 	.dealloc_pd = siw_dealloc_pd,
282 	.dealloc_ucontext = siw_dealloc_ucontext,
283 	.dereg_mr = siw_dereg_mr,
284 	.destroy_cq = siw_destroy_cq,
285 	.destroy_qp = siw_destroy_qp,
286 	.destroy_srq = siw_destroy_srq,
287 	.drain_rq = siw_verbs_rq_flush,
288 	.drain_sq = siw_verbs_sq_flush,
289 	.get_dma_mr = siw_get_dma_mr,
290 	.get_port_immutable = siw_get_port_immutable,
291 	.iw_accept = siw_accept,
292 	.iw_add_ref = siw_qp_get_ref,
293 	.iw_connect = siw_connect,
294 	.iw_create_listen = siw_create_listen,
295 	.iw_destroy_listen = siw_destroy_listen,
296 	.iw_get_qp = siw_get_base_qp,
297 	.iw_reject = siw_reject,
298 	.iw_rem_ref = siw_qp_put_ref,
299 	.map_mr_sg = siw_map_mr_sg,
300 	.mmap = siw_mmap,
301 	.modify_qp = siw_verbs_modify_qp,
302 	.modify_srq = siw_modify_srq,
303 	.poll_cq = siw_poll_cq,
304 	.post_recv = siw_post_receive,
305 	.post_send = siw_post_send,
306 	.post_srq_recv = siw_post_srq_recv,
307 	.query_device = siw_query_device,
308 	.query_gid = siw_query_gid,
309 	.query_pkey = siw_query_pkey,
310 	.query_port = siw_query_port,
311 	.query_qp = siw_query_qp,
312 	.query_srq = siw_query_srq,
313 	.req_notify_cq = siw_req_notify_cq,
314 	.reg_user_mr = siw_reg_user_mr,
315 
316 	INIT_RDMA_OBJ_SIZE(ib_cq, siw_cq, base_cq),
317 	INIT_RDMA_OBJ_SIZE(ib_pd, siw_pd, base_pd),
318 	INIT_RDMA_OBJ_SIZE(ib_srq, siw_srq, base_srq),
319 	INIT_RDMA_OBJ_SIZE(ib_ucontext, siw_ucontext, base_ucontext),
320 };
321 
322 static struct siw_device *siw_device_create(struct net_device *netdev)
323 {
324 	struct siw_device *sdev = NULL;
325 	struct ib_device *base_dev;
326 	struct device *parent = netdev->dev.parent;
327 	int rv;
328 
329 	if (!parent) {
330 		/*
331 		 * The loopback device has no parent device,
332 		 * so it appears as a top-level device. To support
333 		 * loopback device connectivity, take this device
334 		 * as the parent device. Skip all other devices
335 		 * w/o parent device.
336 		 */
337 		if (netdev->type != ARPHRD_LOOPBACK) {
338 			pr_warn("siw: device %s error: no parent device\n",
339 				netdev->name);
340 			return NULL;
341 		}
342 		parent = &netdev->dev;
343 	}
344 	sdev = ib_alloc_device(siw_device, base_dev);
345 	if (!sdev)
346 		return NULL;
347 
348 	base_dev = &sdev->base_dev;
349 
350 	sdev->netdev = netdev;
351 
352 	if (netdev->type != ARPHRD_LOOPBACK) {
353 		memcpy(&base_dev->node_guid, netdev->dev_addr, 6);
354 	} else {
355 		/*
356 		 * The loopback device does not have a HW address,
357 		 * but connection mangagement lib expects gid != 0
358 		 */
359 		size_t gidlen = min_t(size_t, strlen(base_dev->name), 6);
360 
361 		memcpy(&base_dev->node_guid, base_dev->name, gidlen);
362 	}
363 	base_dev->uverbs_cmd_mask =
364 		(1ull << IB_USER_VERBS_CMD_QUERY_DEVICE) |
365 		(1ull << IB_USER_VERBS_CMD_QUERY_PORT) |
366 		(1ull << IB_USER_VERBS_CMD_GET_CONTEXT) |
367 		(1ull << IB_USER_VERBS_CMD_ALLOC_PD) |
368 		(1ull << IB_USER_VERBS_CMD_DEALLOC_PD) |
369 		(1ull << IB_USER_VERBS_CMD_REG_MR) |
370 		(1ull << IB_USER_VERBS_CMD_DEREG_MR) |
371 		(1ull << IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL) |
372 		(1ull << IB_USER_VERBS_CMD_CREATE_CQ) |
373 		(1ull << IB_USER_VERBS_CMD_POLL_CQ) |
374 		(1ull << IB_USER_VERBS_CMD_REQ_NOTIFY_CQ) |
375 		(1ull << IB_USER_VERBS_CMD_DESTROY_CQ) |
376 		(1ull << IB_USER_VERBS_CMD_CREATE_QP) |
377 		(1ull << IB_USER_VERBS_CMD_QUERY_QP) |
378 		(1ull << IB_USER_VERBS_CMD_MODIFY_QP) |
379 		(1ull << IB_USER_VERBS_CMD_DESTROY_QP) |
380 		(1ull << IB_USER_VERBS_CMD_POST_SEND) |
381 		(1ull << IB_USER_VERBS_CMD_POST_RECV) |
382 		(1ull << IB_USER_VERBS_CMD_CREATE_SRQ) |
383 		(1ull << IB_USER_VERBS_CMD_POST_SRQ_RECV) |
384 		(1ull << IB_USER_VERBS_CMD_MODIFY_SRQ) |
385 		(1ull << IB_USER_VERBS_CMD_QUERY_SRQ) |
386 		(1ull << IB_USER_VERBS_CMD_DESTROY_SRQ);
387 
388 	base_dev->node_type = RDMA_NODE_RNIC;
389 	memcpy(base_dev->node_desc, SIW_NODE_DESC_COMMON,
390 	       sizeof(SIW_NODE_DESC_COMMON));
391 
392 	/*
393 	 * Current model (one-to-one device association):
394 	 * One Softiwarp device per net_device or, equivalently,
395 	 * per physical port.
396 	 */
397 	base_dev->phys_port_cnt = 1;
398 	base_dev->dev.parent = parent;
399 	base_dev->dev.dma_ops = &dma_virt_ops;
400 	base_dev->num_comp_vectors = num_possible_cpus();
401 
402 	ib_set_device_ops(base_dev, &siw_device_ops);
403 	rv = ib_device_set_netdev(base_dev, netdev, 1);
404 	if (rv)
405 		goto error;
406 
407 	memcpy(base_dev->iw_ifname, netdev->name,
408 	       sizeof(base_dev->iw_ifname));
409 
410 	/* Disable TCP port mapping */
411 	base_dev->iw_driver_flags = IW_F_NO_PORT_MAP,
412 
413 	sdev->attrs.max_qp = SIW_MAX_QP;
414 	sdev->attrs.max_qp_wr = SIW_MAX_QP_WR;
415 	sdev->attrs.max_ord = SIW_MAX_ORD_QP;
416 	sdev->attrs.max_ird = SIW_MAX_IRD_QP;
417 	sdev->attrs.max_sge = SIW_MAX_SGE;
418 	sdev->attrs.max_sge_rd = SIW_MAX_SGE_RD;
419 	sdev->attrs.max_cq = SIW_MAX_CQ;
420 	sdev->attrs.max_cqe = SIW_MAX_CQE;
421 	sdev->attrs.max_mr = SIW_MAX_MR;
422 	sdev->attrs.max_pd = SIW_MAX_PD;
423 	sdev->attrs.max_mw = SIW_MAX_MW;
424 	sdev->attrs.max_fmr = SIW_MAX_FMR;
425 	sdev->attrs.max_srq = SIW_MAX_SRQ;
426 	sdev->attrs.max_srq_wr = SIW_MAX_SRQ_WR;
427 	sdev->attrs.max_srq_sge = SIW_MAX_SGE;
428 
429 	xa_init_flags(&sdev->qp_xa, XA_FLAGS_ALLOC1);
430 	xa_init_flags(&sdev->mem_xa, XA_FLAGS_ALLOC1);
431 
432 	INIT_LIST_HEAD(&sdev->cep_list);
433 	INIT_LIST_HEAD(&sdev->qp_list);
434 
435 	atomic_set(&sdev->num_ctx, 0);
436 	atomic_set(&sdev->num_srq, 0);
437 	atomic_set(&sdev->num_qp, 0);
438 	atomic_set(&sdev->num_cq, 0);
439 	atomic_set(&sdev->num_mr, 0);
440 	atomic_set(&sdev->num_pd, 0);
441 
442 	sdev->numa_node = dev_to_node(parent);
443 	spin_lock_init(&sdev->lock);
444 
445 	return sdev;
446 error:
447 	ib_dealloc_device(base_dev);
448 
449 	return NULL;
450 }
451 
452 /*
453  * Network link becomes unavailable. Mark all
454  * affected QP's accordingly.
455  */
456 static void siw_netdev_down(struct work_struct *work)
457 {
458 	struct siw_device *sdev =
459 		container_of(work, struct siw_device, netdev_down);
460 
461 	struct siw_qp_attrs qp_attrs;
462 	struct list_head *pos, *tmp;
463 
464 	memset(&qp_attrs, 0, sizeof(qp_attrs));
465 	qp_attrs.state = SIW_QP_STATE_ERROR;
466 
467 	list_for_each_safe(pos, tmp, &sdev->qp_list) {
468 		struct siw_qp *qp = list_entry(pos, struct siw_qp, devq);
469 
470 		down_write(&qp->state_lock);
471 		WARN_ON(siw_qp_modify(qp, &qp_attrs, SIW_QP_ATTR_STATE));
472 		up_write(&qp->state_lock);
473 	}
474 	ib_device_put(&sdev->base_dev);
475 }
476 
477 static void siw_device_goes_down(struct siw_device *sdev)
478 {
479 	if (ib_device_try_get(&sdev->base_dev)) {
480 		INIT_WORK(&sdev->netdev_down, siw_netdev_down);
481 		schedule_work(&sdev->netdev_down);
482 	}
483 }
484 
485 static int siw_netdev_event(struct notifier_block *nb, unsigned long event,
486 			    void *arg)
487 {
488 	struct net_device *netdev = netdev_notifier_info_to_dev(arg);
489 	struct ib_device *base_dev;
490 	struct siw_device *sdev;
491 
492 	dev_dbg(&netdev->dev, "siw: event %lu\n", event);
493 
494 	if (dev_net(netdev) != &init_net)
495 		return NOTIFY_OK;
496 
497 	base_dev = ib_device_get_by_netdev(netdev, RDMA_DRIVER_SIW);
498 	if (!base_dev)
499 		return NOTIFY_OK;
500 
501 	sdev = to_siw_dev(base_dev);
502 
503 	switch (event) {
504 	case NETDEV_UP:
505 		sdev->state = IB_PORT_ACTIVE;
506 		siw_port_event(sdev, 1, IB_EVENT_PORT_ACTIVE);
507 		break;
508 
509 	case NETDEV_GOING_DOWN:
510 		siw_device_goes_down(sdev);
511 		break;
512 
513 	case NETDEV_DOWN:
514 		sdev->state = IB_PORT_DOWN;
515 		siw_port_event(sdev, 1, IB_EVENT_PORT_ERR);
516 		break;
517 
518 	case NETDEV_REGISTER:
519 		/*
520 		 * Device registration now handled only by
521 		 * rdma netlink commands. So it shall be impossible
522 		 * to end up here with a valid siw device.
523 		 */
524 		siw_dbg(base_dev, "unexpected NETDEV_REGISTER event\n");
525 		break;
526 
527 	case NETDEV_UNREGISTER:
528 		ib_unregister_device_queued(&sdev->base_dev);
529 		break;
530 
531 	case NETDEV_CHANGEADDR:
532 		siw_port_event(sdev, 1, IB_EVENT_LID_CHANGE);
533 		break;
534 	/*
535 	 * Todo: Below netdev events are currently not handled.
536 	 */
537 	case NETDEV_CHANGEMTU:
538 	case NETDEV_CHANGE:
539 		break;
540 
541 	default:
542 		break;
543 	}
544 	ib_device_put(&sdev->base_dev);
545 
546 	return NOTIFY_OK;
547 }
548 
549 static struct notifier_block siw_netdev_nb = {
550 	.notifier_call = siw_netdev_event,
551 };
552 
553 static int siw_newlink(const char *basedev_name, struct net_device *netdev)
554 {
555 	struct ib_device *base_dev;
556 	struct siw_device *sdev = NULL;
557 	int rv = -ENOMEM;
558 
559 	if (!siw_dev_qualified(netdev))
560 		return -EINVAL;
561 
562 	base_dev = ib_device_get_by_netdev(netdev, RDMA_DRIVER_SIW);
563 	if (base_dev) {
564 		ib_device_put(base_dev);
565 		return -EEXIST;
566 	}
567 	sdev = siw_device_create(netdev);
568 	if (sdev) {
569 		dev_dbg(&netdev->dev, "siw: new device\n");
570 
571 		if (netif_running(netdev) && netif_carrier_ok(netdev))
572 			sdev->state = IB_PORT_ACTIVE;
573 		else
574 			sdev->state = IB_PORT_DOWN;
575 
576 		rv = siw_device_register(sdev, basedev_name);
577 		if (rv)
578 			ib_dealloc_device(&sdev->base_dev);
579 	}
580 	return rv;
581 }
582 
583 static struct rdma_link_ops siw_link_ops = {
584 	.type = "siw",
585 	.newlink = siw_newlink,
586 };
587 
588 /*
589  * siw_init_module - Initialize Softiwarp module and register with netdev
590  *                   subsystem.
591  */
592 static __init int siw_init_module(void)
593 {
594 	int rv;
595 	int nr_cpu;
596 
597 	if (SENDPAGE_THRESH < SIW_MAX_INLINE) {
598 		pr_info("siw: sendpage threshold too small: %u\n",
599 			(int)SENDPAGE_THRESH);
600 		rv = -EINVAL;
601 		goto out_error;
602 	}
603 	rv = siw_init_cpulist();
604 	if (rv)
605 		goto out_error;
606 
607 	rv = siw_cm_init();
608 	if (rv)
609 		goto out_error;
610 
611 	if (!siw_create_tx_threads()) {
612 		pr_info("siw: Could not start any TX thread\n");
613 		rv = -ENOMEM;
614 		goto out_error;
615 	}
616 	/*
617 	 * Locate CRC32 algorithm. If unsuccessful, fail
618 	 * loading siw only, if CRC is required.
619 	 */
620 	siw_crypto_shash = crypto_alloc_shash("crc32c", 0, 0);
621 	if (IS_ERR(siw_crypto_shash)) {
622 		pr_info("siw: Loading CRC32c failed: %ld\n",
623 			PTR_ERR(siw_crypto_shash));
624 		siw_crypto_shash = NULL;
625 		if (mpa_crc_required) {
626 			rv = -EOPNOTSUPP;
627 			goto out_error;
628 		}
629 	}
630 	rv = register_netdevice_notifier(&siw_netdev_nb);
631 	if (rv)
632 		goto out_error;
633 
634 	rdma_link_register(&siw_link_ops);
635 
636 	pr_info("SoftiWARP attached\n");
637 	return 0;
638 
639 out_error:
640 	for (nr_cpu = 0; nr_cpu < nr_cpu_ids; nr_cpu++) {
641 		if (siw_tx_thread[nr_cpu]) {
642 			siw_stop_tx_thread(nr_cpu);
643 			siw_tx_thread[nr_cpu] = NULL;
644 		}
645 	}
646 	if (siw_crypto_shash)
647 		crypto_free_shash(siw_crypto_shash);
648 
649 	pr_info("SoftIWARP attach failed. Error: %d\n", rv);
650 
651 	siw_cm_exit();
652 	siw_destroy_cpulist();
653 
654 	return rv;
655 }
656 
657 static void __exit siw_exit_module(void)
658 {
659 	int cpu;
660 
661 	for_each_possible_cpu(cpu) {
662 		if (siw_tx_thread[cpu]) {
663 			siw_stop_tx_thread(cpu);
664 			siw_tx_thread[cpu] = NULL;
665 		}
666 	}
667 	unregister_netdevice_notifier(&siw_netdev_nb);
668 	rdma_link_unregister(&siw_link_ops);
669 	ib_unregister_driver(RDMA_DRIVER_SIW);
670 
671 	siw_cm_exit();
672 
673 	siw_destroy_cpulist();
674 
675 	if (siw_crypto_shash)
676 		crypto_free_shash(siw_crypto_shash);
677 
678 	pr_info("SoftiWARP detached\n");
679 }
680 
681 module_init(siw_init_module);
682 module_exit(siw_exit_module);
683 
684 MODULE_ALIAS_RDMA_LINK("siw");
685