xref: /openbmc/linux/net/smc/smc_pnet.c (revision 3557b3fd)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4  *
5  *  Generic netlink support functions to configure an SMC-R PNET table
6  *
7  *  Copyright IBM Corp. 2016
8  *
9  *  Author(s):  Thomas Richter <tmricht@linux.vnet.ibm.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/list.h>
14 #include <linux/ctype.h>
15 #include <net/netlink.h>
16 #include <net/genetlink.h>
17 
18 #include <uapi/linux/if.h>
19 #include <uapi/linux/smc.h>
20 
21 #include <rdma/ib_verbs.h>
22 
23 #include <net/netns/generic.h>
24 #include "smc_netns.h"
25 
26 #include "smc_pnet.h"
27 #include "smc_ib.h"
28 #include "smc_ism.h"
29 #include "smc_core.h"
30 
31 #define SMC_ASCII_BLANK 32
32 
33 static struct net_device *pnet_find_base_ndev(struct net_device *ndev);
34 
35 static struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
36 	[SMC_PNETID_NAME] = {
37 		.type = NLA_NUL_STRING,
38 		.len = SMC_MAX_PNETID_LEN
39 	},
40 	[SMC_PNETID_ETHNAME] = {
41 		.type = NLA_NUL_STRING,
42 		.len = IFNAMSIZ - 1
43 	},
44 	[SMC_PNETID_IBNAME] = {
45 		.type = NLA_NUL_STRING,
46 		.len = IB_DEVICE_NAME_MAX - 1
47 	},
48 	[SMC_PNETID_IBPORT] = { .type = NLA_U8 }
49 };
50 
51 static struct genl_family smc_pnet_nl_family;
52 
53 /**
54  * struct smc_user_pnetentry - pnet identifier name entry for/from user
55  * @list: List node.
56  * @pnet_name: Pnet identifier name
57  * @ndev: pointer to network device.
58  * @smcibdev: Pointer to IB device.
59  * @ib_port: Port of IB device.
60  * @smcd_dev: Pointer to smcd device.
61  */
62 struct smc_user_pnetentry {
63 	struct list_head list;
64 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
65 	struct net_device *ndev;
66 	struct smc_ib_device *smcibdev;
67 	u8 ib_port;
68 	struct smcd_dev *smcd_dev;
69 };
70 
71 /* pnet entry stored in pnet table */
72 struct smc_pnetentry {
73 	struct list_head list;
74 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
75 	struct net_device *ndev;
76 };
77 
78 /* Check if two given pnetids match */
79 static bool smc_pnet_match(u8 *pnetid1, u8 *pnetid2)
80 {
81 	int i;
82 
83 	for (i = 0; i < SMC_MAX_PNETID_LEN; i++) {
84 		if ((pnetid1[i] == 0 || pnetid1[i] == SMC_ASCII_BLANK) &&
85 		    (pnetid2[i] == 0 || pnetid2[i] == SMC_ASCII_BLANK))
86 			break;
87 		if (pnetid1[i] != pnetid2[i])
88 			return false;
89 	}
90 	return true;
91 }
92 
93 /* Remove a pnetid from the pnet table.
94  */
95 static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
96 {
97 	struct smc_pnetentry *pnetelem, *tmp_pe;
98 	struct smc_pnettable *pnettable;
99 	struct smc_ib_device *ibdev;
100 	struct smcd_dev *smcd_dev;
101 	struct smc_net *sn;
102 	int rc = -ENOENT;
103 	int ibport;
104 
105 	/* get pnettable for namespace */
106 	sn = net_generic(net, smc_net_id);
107 	pnettable = &sn->pnettable;
108 
109 	/* remove netdevices */
110 	write_lock(&pnettable->lock);
111 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
112 				 list) {
113 		if (!pnet_name ||
114 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
115 			list_del(&pnetelem->list);
116 			dev_put(pnetelem->ndev);
117 			kfree(pnetelem);
118 			rc = 0;
119 		}
120 	}
121 	write_unlock(&pnettable->lock);
122 
123 	/* if this is not the initial namespace, stop here */
124 	if (net != &init_net)
125 		return rc;
126 
127 	/* remove ib devices */
128 	spin_lock(&smc_ib_devices.lock);
129 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
130 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
131 			if (ibdev->pnetid_by_user[ibport] &&
132 			    (!pnet_name ||
133 			     smc_pnet_match(pnet_name,
134 					    ibdev->pnetid[ibport]))) {
135 				memset(ibdev->pnetid[ibport], 0,
136 				       SMC_MAX_PNETID_LEN);
137 				ibdev->pnetid_by_user[ibport] = false;
138 				rc = 0;
139 			}
140 		}
141 	}
142 	spin_unlock(&smc_ib_devices.lock);
143 	/* remove smcd devices */
144 	spin_lock(&smcd_dev_list.lock);
145 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
146 		if (smcd_dev->pnetid_by_user &&
147 		    (!pnet_name ||
148 		     smc_pnet_match(pnet_name, smcd_dev->pnetid))) {
149 			memset(smcd_dev->pnetid, 0, SMC_MAX_PNETID_LEN);
150 			smcd_dev->pnetid_by_user = false;
151 			rc = 0;
152 		}
153 	}
154 	spin_unlock(&smcd_dev_list.lock);
155 	return rc;
156 }
157 
158 /* Remove a pnet entry mentioning a given network device from the pnet table.
159  */
160 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
161 {
162 	struct smc_pnetentry *pnetelem, *tmp_pe;
163 	struct smc_pnettable *pnettable;
164 	struct net *net = dev_net(ndev);
165 	struct smc_net *sn;
166 	int rc = -ENOENT;
167 
168 	/* get pnettable for namespace */
169 	sn = net_generic(net, smc_net_id);
170 	pnettable = &sn->pnettable;
171 
172 	write_lock(&pnettable->lock);
173 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
174 		if (pnetelem->ndev == ndev) {
175 			list_del(&pnetelem->list);
176 			dev_put(pnetelem->ndev);
177 			kfree(pnetelem);
178 			rc = 0;
179 			break;
180 		}
181 	}
182 	write_unlock(&pnettable->lock);
183 	return rc;
184 }
185 
186 /* Append a pnetid to the end of the pnet table if not already on this list.
187  */
188 static int smc_pnet_enter(struct smc_pnettable *pnettable,
189 			  struct smc_user_pnetentry *new_pnetelem)
190 {
191 	u8 pnet_null[SMC_MAX_PNETID_LEN] = {0};
192 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
193 	struct smc_pnetentry *tmp_pnetelem;
194 	struct smc_pnetentry *pnetelem;
195 	bool new_smcddev = false;
196 	struct net_device *ndev;
197 	bool new_netdev = true;
198 	bool new_ibdev = false;
199 
200 	if (new_pnetelem->smcibdev) {
201 		struct smc_ib_device *ib_dev = new_pnetelem->smcibdev;
202 		int ib_port = new_pnetelem->ib_port;
203 
204 		spin_lock(&smc_ib_devices.lock);
205 		if (smc_pnet_match(ib_dev->pnetid[ib_port - 1], pnet_null)) {
206 			memcpy(ib_dev->pnetid[ib_port - 1],
207 			       new_pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
208 			ib_dev->pnetid_by_user[ib_port - 1] = true;
209 			new_ibdev = true;
210 		}
211 		spin_unlock(&smc_ib_devices.lock);
212 	}
213 	if (new_pnetelem->smcd_dev) {
214 		struct smcd_dev *smcd_dev = new_pnetelem->smcd_dev;
215 
216 		spin_lock(&smcd_dev_list.lock);
217 		if (smc_pnet_match(smcd_dev->pnetid, pnet_null)) {
218 			memcpy(smcd_dev->pnetid, new_pnetelem->pnet_name,
219 			       SMC_MAX_PNETID_LEN);
220 			smcd_dev->pnetid_by_user = true;
221 			new_smcddev = true;
222 		}
223 		spin_unlock(&smcd_dev_list.lock);
224 	}
225 
226 	if (!new_pnetelem->ndev)
227 		return (new_ibdev || new_smcddev) ? 0 : -EEXIST;
228 
229 	/* check if (base) netdev already has a pnetid. If there is one, we do
230 	 * not want to add a pnet table entry
231 	 */
232 	ndev = pnet_find_base_ndev(new_pnetelem->ndev);
233 	if (!smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
234 				    ndev_pnetid))
235 		return (new_ibdev || new_smcddev) ? 0 : -EEXIST;
236 
237 	/* add a new netdev entry to the pnet table if there isn't one */
238 	tmp_pnetelem = kzalloc(sizeof(*pnetelem), GFP_KERNEL);
239 	if (!tmp_pnetelem)
240 		return -ENOMEM;
241 	memcpy(tmp_pnetelem->pnet_name, new_pnetelem->pnet_name,
242 	       SMC_MAX_PNETID_LEN);
243 	tmp_pnetelem->ndev = new_pnetelem->ndev;
244 
245 	write_lock(&pnettable->lock);
246 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
247 		if (pnetelem->ndev == new_pnetelem->ndev)
248 			new_netdev = false;
249 	}
250 	if (new_netdev) {
251 		dev_hold(tmp_pnetelem->ndev);
252 		list_add_tail(&tmp_pnetelem->list, &pnettable->pnetlist);
253 		write_unlock(&pnettable->lock);
254 	} else {
255 		write_unlock(&pnettable->lock);
256 		kfree(tmp_pnetelem);
257 	}
258 
259 	return (new_netdev || new_ibdev || new_smcddev) ? 0 : -EEXIST;
260 }
261 
262 /* The limit for pnetid is 16 characters.
263  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
264  * Lower case letters are converted to upper case.
265  * Interior blanks should not be used.
266  */
267 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
268 {
269 	char *bf = skip_spaces(pnet_name);
270 	size_t len = strlen(bf);
271 	char *end = bf + len;
272 
273 	if (!len)
274 		return false;
275 	while (--end >= bf && isspace(*end))
276 		;
277 	if (end - bf >= SMC_MAX_PNETID_LEN)
278 		return false;
279 	while (bf <= end) {
280 		if (!isalnum(*bf))
281 			return false;
282 		*pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
283 		bf++;
284 	}
285 	*pnetid = '\0';
286 	return true;
287 }
288 
289 /* Find an infiniband device by a given name. The device might not exist. */
290 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
291 {
292 	struct smc_ib_device *ibdev;
293 
294 	spin_lock(&smc_ib_devices.lock);
295 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
296 		if (!strncmp(ibdev->ibdev->name, ib_name,
297 			     sizeof(ibdev->ibdev->name)) ||
298 		    !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name,
299 			     IB_DEVICE_NAME_MAX - 1)) {
300 			goto out;
301 		}
302 	}
303 	ibdev = NULL;
304 out:
305 	spin_unlock(&smc_ib_devices.lock);
306 	return ibdev;
307 }
308 
309 /* Find an smcd device by a given name. The device might not exist. */
310 static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
311 {
312 	struct smcd_dev *smcd_dev;
313 
314 	spin_lock(&smcd_dev_list.lock);
315 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
316 		if (!strncmp(dev_name(&smcd_dev->dev), smcd_name,
317 			     IB_DEVICE_NAME_MAX - 1))
318 			goto out;
319 	}
320 	smcd_dev = NULL;
321 out:
322 	spin_unlock(&smcd_dev_list.lock);
323 	return smcd_dev;
324 }
325 
326 /* Parse the supplied netlink attributes and fill a pnetentry structure.
327  * For ethernet and infiniband device names verify that the devices exist.
328  */
329 static int smc_pnet_fill_entry(struct net *net,
330 			       struct smc_user_pnetentry *pnetelem,
331 			       struct nlattr *tb[])
332 {
333 	char *string, *ibname;
334 	int rc;
335 
336 	memset(pnetelem, 0, sizeof(*pnetelem));
337 	INIT_LIST_HEAD(&pnetelem->list);
338 
339 	rc = -EINVAL;
340 	if (!tb[SMC_PNETID_NAME])
341 		goto error;
342 	string = (char *)nla_data(tb[SMC_PNETID_NAME]);
343 	if (!smc_pnetid_valid(string, pnetelem->pnet_name))
344 		goto error;
345 
346 	rc = -EINVAL;
347 	if (tb[SMC_PNETID_ETHNAME]) {
348 		string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
349 		pnetelem->ndev = dev_get_by_name(net, string);
350 		if (!pnetelem->ndev)
351 			goto error;
352 	}
353 
354 	/* if this is not the initial namespace, stop here */
355 	if (net != &init_net)
356 		return 0;
357 
358 	rc = -EINVAL;
359 	if (tb[SMC_PNETID_IBNAME]) {
360 		ibname = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
361 		ibname = strim(ibname);
362 		pnetelem->smcibdev = smc_pnet_find_ib(ibname);
363 		pnetelem->smcd_dev = smc_pnet_find_smcd(ibname);
364 		if (!pnetelem->smcibdev && !pnetelem->smcd_dev)
365 			goto error;
366 		if (pnetelem->smcibdev) {
367 			if (!tb[SMC_PNETID_IBPORT])
368 				goto error;
369 			pnetelem->ib_port = nla_get_u8(tb[SMC_PNETID_IBPORT]);
370 			if (pnetelem->ib_port < 1 ||
371 			    pnetelem->ib_port > SMC_MAX_PORTS)
372 				goto error;
373 		}
374 	}
375 
376 	return 0;
377 
378 error:
379 	if (pnetelem->ndev)
380 		dev_put(pnetelem->ndev);
381 	return rc;
382 }
383 
384 /* Convert an smc_pnetentry to a netlink attribute sequence */
385 static int smc_pnet_set_nla(struct sk_buff *msg,
386 			    struct smc_user_pnetentry *pnetelem)
387 {
388 	if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name))
389 		return -1;
390 	if (pnetelem->ndev) {
391 		if (nla_put_string(msg, SMC_PNETID_ETHNAME,
392 				   pnetelem->ndev->name))
393 			return -1;
394 	} else {
395 		if (nla_put_string(msg, SMC_PNETID_ETHNAME, "n/a"))
396 			return -1;
397 	}
398 	if (pnetelem->smcibdev) {
399 		if (nla_put_string(msg, SMC_PNETID_IBNAME,
400 			dev_name(pnetelem->smcibdev->ibdev->dev.parent)) ||
401 		    nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
402 			return -1;
403 	} else if (pnetelem->smcd_dev) {
404 		if (nla_put_string(msg, SMC_PNETID_IBNAME,
405 				   dev_name(&pnetelem->smcd_dev->dev)) ||
406 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 1))
407 			return -1;
408 	} else {
409 		if (nla_put_string(msg, SMC_PNETID_IBNAME, "n/a") ||
410 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 0xff))
411 			return -1;
412 	}
413 
414 	return 0;
415 }
416 
417 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
418 {
419 	struct net *net = genl_info_net(info);
420 	struct smc_user_pnetentry pnetelem;
421 	struct smc_pnettable *pnettable;
422 	struct smc_net *sn;
423 	int rc;
424 
425 	/* get pnettable for namespace */
426 	sn = net_generic(net, smc_net_id);
427 	pnettable = &sn->pnettable;
428 
429 	rc = smc_pnet_fill_entry(net, &pnetelem, info->attrs);
430 	if (!rc)
431 		rc = smc_pnet_enter(pnettable, &pnetelem);
432 	if (pnetelem.ndev)
433 		dev_put(pnetelem.ndev);
434 	return rc;
435 }
436 
437 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
438 {
439 	struct net *net = genl_info_net(info);
440 
441 	if (!info->attrs[SMC_PNETID_NAME])
442 		return -EINVAL;
443 	return smc_pnet_remove_by_pnetid(net,
444 				(char *)nla_data(info->attrs[SMC_PNETID_NAME]));
445 }
446 
447 static int smc_pnet_dump_start(struct netlink_callback *cb)
448 {
449 	cb->args[0] = 0;
450 	return 0;
451 }
452 
453 static int smc_pnet_dumpinfo(struct sk_buff *skb,
454 			     u32 portid, u32 seq, u32 flags,
455 			     struct smc_user_pnetentry *pnetelem)
456 {
457 	void *hdr;
458 
459 	hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
460 			  flags, SMC_PNETID_GET);
461 	if (!hdr)
462 		return -ENOMEM;
463 	if (smc_pnet_set_nla(skb, pnetelem) < 0) {
464 		genlmsg_cancel(skb, hdr);
465 		return -EMSGSIZE;
466 	}
467 	genlmsg_end(skb, hdr);
468 	return 0;
469 }
470 
471 static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
472 			  u32 seq, u8 *pnetid, int start_idx)
473 {
474 	struct smc_user_pnetentry tmp_entry;
475 	struct smc_pnettable *pnettable;
476 	struct smc_pnetentry *pnetelem;
477 	struct smc_ib_device *ibdev;
478 	struct smcd_dev *smcd_dev;
479 	struct smc_net *sn;
480 	int idx = 0;
481 	int ibport;
482 
483 	/* get pnettable for namespace */
484 	sn = net_generic(net, smc_net_id);
485 	pnettable = &sn->pnettable;
486 
487 	/* dump netdevices */
488 	read_lock(&pnettable->lock);
489 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
490 		if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
491 			continue;
492 		if (idx++ < start_idx)
493 			continue;
494 		memset(&tmp_entry, 0, sizeof(tmp_entry));
495 		memcpy(&tmp_entry.pnet_name, pnetelem->pnet_name,
496 		       SMC_MAX_PNETID_LEN);
497 		tmp_entry.ndev = pnetelem->ndev;
498 		if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
499 				      &tmp_entry)) {
500 			--idx;
501 			break;
502 		}
503 	}
504 	read_unlock(&pnettable->lock);
505 
506 	/* if this is not the initial namespace, stop here */
507 	if (net != &init_net)
508 		return idx;
509 
510 	/* dump ib devices */
511 	spin_lock(&smc_ib_devices.lock);
512 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
513 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
514 			if (ibdev->pnetid_by_user[ibport]) {
515 				if (pnetid &&
516 				    !smc_pnet_match(ibdev->pnetid[ibport],
517 						    pnetid))
518 					continue;
519 				if (idx++ < start_idx)
520 					continue;
521 				memset(&tmp_entry, 0, sizeof(tmp_entry));
522 				memcpy(&tmp_entry.pnet_name,
523 				       ibdev->pnetid[ibport],
524 				       SMC_MAX_PNETID_LEN);
525 				tmp_entry.smcibdev = ibdev;
526 				tmp_entry.ib_port = ibport + 1;
527 				if (smc_pnet_dumpinfo(skb, portid, seq,
528 						      NLM_F_MULTI,
529 						      &tmp_entry)) {
530 					--idx;
531 					break;
532 				}
533 			}
534 		}
535 	}
536 	spin_unlock(&smc_ib_devices.lock);
537 
538 	/* dump smcd devices */
539 	spin_lock(&smcd_dev_list.lock);
540 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
541 		if (smcd_dev->pnetid_by_user) {
542 			if (pnetid && !smc_pnet_match(smcd_dev->pnetid, pnetid))
543 				continue;
544 			if (idx++ < start_idx)
545 				continue;
546 			memset(&tmp_entry, 0, sizeof(tmp_entry));
547 			memcpy(&tmp_entry.pnet_name, smcd_dev->pnetid,
548 			       SMC_MAX_PNETID_LEN);
549 			tmp_entry.smcd_dev = smcd_dev;
550 			if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
551 					      &tmp_entry)) {
552 				--idx;
553 				break;
554 			}
555 		}
556 	}
557 	spin_unlock(&smcd_dev_list.lock);
558 
559 	return idx;
560 }
561 
562 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
563 {
564 	struct net *net = sock_net(skb->sk);
565 	int idx;
566 
567 	idx = _smc_pnet_dump(net, skb, NETLINK_CB(cb->skb).portid,
568 			     cb->nlh->nlmsg_seq, NULL, cb->args[0]);
569 
570 	cb->args[0] = idx;
571 	return skb->len;
572 }
573 
574 /* Retrieve one PNETID entry */
575 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
576 {
577 	struct net *net = genl_info_net(info);
578 	struct sk_buff *msg;
579 	void *hdr;
580 
581 	if (!info->attrs[SMC_PNETID_NAME])
582 		return -EINVAL;
583 
584 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
585 	if (!msg)
586 		return -ENOMEM;
587 
588 	_smc_pnet_dump(net, msg, info->snd_portid, info->snd_seq,
589 		       nla_data(info->attrs[SMC_PNETID_NAME]), 0);
590 
591 	/* finish multi part message and send it */
592 	hdr = nlmsg_put(msg, info->snd_portid, info->snd_seq, NLMSG_DONE, 0,
593 			NLM_F_MULTI);
594 	if (!hdr) {
595 		nlmsg_free(msg);
596 		return -EMSGSIZE;
597 	}
598 	return genlmsg_reply(msg, info);
599 }
600 
601 /* Remove and delete all pnetids from pnet table.
602  */
603 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
604 {
605 	struct net *net = genl_info_net(info);
606 
607 	smc_pnet_remove_by_pnetid(net, NULL);
608 	return 0;
609 }
610 
611 /* SMC_PNETID generic netlink operation definition */
612 static const struct genl_ops smc_pnet_ops[] = {
613 	{
614 		.cmd = SMC_PNETID_GET,
615 		.flags = GENL_ADMIN_PERM,
616 		.doit = smc_pnet_get,
617 		.dumpit = smc_pnet_dump,
618 		.start = smc_pnet_dump_start
619 	},
620 	{
621 		.cmd = SMC_PNETID_ADD,
622 		.flags = GENL_ADMIN_PERM,
623 		.doit = smc_pnet_add
624 	},
625 	{
626 		.cmd = SMC_PNETID_DEL,
627 		.flags = GENL_ADMIN_PERM,
628 		.doit = smc_pnet_del
629 	},
630 	{
631 		.cmd = SMC_PNETID_FLUSH,
632 		.flags = GENL_ADMIN_PERM,
633 		.doit = smc_pnet_flush
634 	}
635 };
636 
637 /* SMC_PNETID family definition */
638 static struct genl_family smc_pnet_nl_family __ro_after_init = {
639 	.hdrsize = 0,
640 	.name = SMCR_GENL_FAMILY_NAME,
641 	.version = SMCR_GENL_FAMILY_VERSION,
642 	.maxattr = SMC_PNETID_MAX,
643 	.policy = smc_pnet_policy,
644 	.netnsok = true,
645 	.module = THIS_MODULE,
646 	.ops = smc_pnet_ops,
647 	.n_ops =  ARRAY_SIZE(smc_pnet_ops)
648 };
649 
650 static int smc_pnet_netdev_event(struct notifier_block *this,
651 				 unsigned long event, void *ptr)
652 {
653 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
654 
655 	switch (event) {
656 	case NETDEV_REBOOT:
657 	case NETDEV_UNREGISTER:
658 		smc_pnet_remove_by_ndev(event_dev);
659 		return NOTIFY_OK;
660 	default:
661 		return NOTIFY_DONE;
662 	}
663 }
664 
665 static struct notifier_block smc_netdev_notifier = {
666 	.notifier_call = smc_pnet_netdev_event
667 };
668 
669 /* init network namespace */
670 int smc_pnet_net_init(struct net *net)
671 {
672 	struct smc_net *sn = net_generic(net, smc_net_id);
673 	struct smc_pnettable *pnettable = &sn->pnettable;
674 
675 	INIT_LIST_HEAD(&pnettable->pnetlist);
676 	rwlock_init(&pnettable->lock);
677 
678 	return 0;
679 }
680 
681 int __init smc_pnet_init(void)
682 {
683 	int rc;
684 
685 	rc = genl_register_family(&smc_pnet_nl_family);
686 	if (rc)
687 		return rc;
688 	rc = register_netdevice_notifier(&smc_netdev_notifier);
689 	if (rc)
690 		genl_unregister_family(&smc_pnet_nl_family);
691 	return rc;
692 }
693 
694 /* exit network namespace */
695 void smc_pnet_net_exit(struct net *net)
696 {
697 	/* flush pnet table */
698 	smc_pnet_remove_by_pnetid(net, NULL);
699 }
700 
701 void smc_pnet_exit(void)
702 {
703 	unregister_netdevice_notifier(&smc_netdev_notifier);
704 	genl_unregister_family(&smc_pnet_nl_family);
705 }
706 
707 /* Determine one base device for stacked net devices.
708  * If the lower device level contains more than one devices
709  * (for instance with bonding slaves), just the first device
710  * is used to reach a base device.
711  */
712 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
713 {
714 	int i, nest_lvl;
715 
716 	rtnl_lock();
717 	nest_lvl = dev_get_nest_level(ndev);
718 	for (i = 0; i < nest_lvl; i++) {
719 		struct list_head *lower = &ndev->adj_list.lower;
720 
721 		if (list_empty(lower))
722 			break;
723 		lower = lower->next;
724 		ndev = netdev_lower_get_next(ndev, &lower);
725 	}
726 	rtnl_unlock();
727 	return ndev;
728 }
729 
730 static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
731 					      u8 *pnetid)
732 {
733 	struct smc_pnettable *pnettable;
734 	struct net *net = dev_net(ndev);
735 	struct smc_pnetentry *pnetelem;
736 	struct smc_net *sn;
737 	int rc = -ENOENT;
738 
739 	/* get pnettable for namespace */
740 	sn = net_generic(net, smc_net_id);
741 	pnettable = &sn->pnettable;
742 
743 	read_lock(&pnettable->lock);
744 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
745 		if (ndev == pnetelem->ndev) {
746 			/* get pnetid of netdev device */
747 			memcpy(pnetid, pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
748 			rc = 0;
749 			break;
750 		}
751 	}
752 	read_unlock(&pnettable->lock);
753 	return rc;
754 }
755 
756 /* if handshake network device belongs to a roce device, return its
757  * IB device and port
758  */
759 static void smc_pnet_find_rdma_dev(struct net_device *netdev,
760 				   struct smc_init_info *ini)
761 {
762 	struct smc_ib_device *ibdev;
763 
764 	spin_lock(&smc_ib_devices.lock);
765 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
766 		struct net_device *ndev;
767 		int i;
768 
769 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
770 			if (!rdma_is_port_valid(ibdev->ibdev, i))
771 				continue;
772 			if (!ibdev->ibdev->ops.get_netdev)
773 				continue;
774 			ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
775 			if (!ndev)
776 				continue;
777 			dev_put(ndev);
778 			if (netdev == ndev &&
779 			    smc_ib_port_active(ibdev, i) &&
780 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
781 						  ini->ib_gid, NULL)) {
782 				ini->ib_dev = ibdev;
783 				ini->ib_port = i;
784 				break;
785 			}
786 		}
787 	}
788 	spin_unlock(&smc_ib_devices.lock);
789 }
790 
791 /* Determine the corresponding IB device port based on the hardware PNETID.
792  * Searching stops at the first matching active IB device port with vlan_id
793  * configured.
794  * If nothing found, check pnetid table.
795  * If nothing found, try to use handshake device
796  */
797 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
798 					 struct smc_init_info *ini)
799 {
800 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
801 	struct smc_ib_device *ibdev;
802 	int i;
803 
804 	ndev = pnet_find_base_ndev(ndev);
805 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
806 				   ndev_pnetid) &&
807 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
808 		smc_pnet_find_rdma_dev(ndev, ini);
809 		return; /* pnetid could not be determined */
810 	}
811 
812 	spin_lock(&smc_ib_devices.lock);
813 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
814 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
815 			if (!rdma_is_port_valid(ibdev->ibdev, i))
816 				continue;
817 			if (smc_pnet_match(ibdev->pnetid[i - 1], ndev_pnetid) &&
818 			    smc_ib_port_active(ibdev, i) &&
819 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
820 						  ini->ib_gid, NULL)) {
821 				ini->ib_dev = ibdev;
822 				ini->ib_port = i;
823 				goto out;
824 			}
825 		}
826 	}
827 out:
828 	spin_unlock(&smc_ib_devices.lock);
829 }
830 
831 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
832 					struct smc_init_info *ini)
833 {
834 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
835 	struct smcd_dev *ismdev;
836 
837 	ndev = pnet_find_base_ndev(ndev);
838 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
839 				   ndev_pnetid) &&
840 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
841 		return; /* pnetid could not be determined */
842 
843 	spin_lock(&smcd_dev_list.lock);
844 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
845 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid)) {
846 			ini->ism_dev = ismdev;
847 			break;
848 		}
849 	}
850 	spin_unlock(&smcd_dev_list.lock);
851 }
852 
853 /* PNET table analysis for a given sock:
854  * determine ib_device and port belonging to used internal TCP socket
855  * ethernet interface.
856  */
857 void smc_pnet_find_roce_resource(struct sock *sk, struct smc_init_info *ini)
858 {
859 	struct dst_entry *dst = sk_dst_get(sk);
860 
861 	ini->ib_dev = NULL;
862 	ini->ib_port = 0;
863 	if (!dst)
864 		goto out;
865 	if (!dst->dev)
866 		goto out_rel;
867 
868 	smc_pnet_find_roce_by_pnetid(dst->dev, ini);
869 
870 out_rel:
871 	dst_release(dst);
872 out:
873 	return;
874 }
875 
876 void smc_pnet_find_ism_resource(struct sock *sk, struct smc_init_info *ini)
877 {
878 	struct dst_entry *dst = sk_dst_get(sk);
879 
880 	ini->ism_dev = NULL;
881 	if (!dst)
882 		goto out;
883 	if (!dst->dev)
884 		goto out_rel;
885 
886 	smc_pnet_find_ism_by_pnetid(dst->dev, ini);
887 
888 out_rel:
889 	dst_release(dst);
890 out:
891 	return;
892 }
893