xref: /openbmc/linux/net/smc/smc_pnet.c (revision f9a82c48)
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 
30 #define SMC_ASCII_BLANK 32
31 
32 static struct net_device *pnet_find_base_ndev(struct net_device *ndev);
33 
34 static struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
35 	[SMC_PNETID_NAME] = {
36 		.type = NLA_NUL_STRING,
37 		.len = SMC_MAX_PNETID_LEN
38 	},
39 	[SMC_PNETID_ETHNAME] = {
40 		.type = NLA_NUL_STRING,
41 		.len = IFNAMSIZ - 1
42 	},
43 	[SMC_PNETID_IBNAME] = {
44 		.type = NLA_NUL_STRING,
45 		.len = IB_DEVICE_NAME_MAX - 1
46 	},
47 	[SMC_PNETID_IBPORT] = { .type = NLA_U8 }
48 };
49 
50 static struct genl_family smc_pnet_nl_family;
51 
52 /**
53  * struct smc_user_pnetentry - pnet identifier name entry for/from user
54  * @list: List node.
55  * @pnet_name: Pnet identifier name
56  * @ndev: pointer to network device.
57  * @smcibdev: Pointer to IB device.
58  * @ib_port: Port of IB device.
59  * @smcd_dev: Pointer to smcd device.
60  */
61 struct smc_user_pnetentry {
62 	struct list_head list;
63 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
64 	struct net_device *ndev;
65 	struct smc_ib_device *smcibdev;
66 	u8 ib_port;
67 	struct smcd_dev *smcd_dev;
68 };
69 
70 /* pnet entry stored in pnet table */
71 struct smc_pnetentry {
72 	struct list_head list;
73 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
74 	struct net_device *ndev;
75 };
76 
77 /* Check if two given pnetids match */
78 static bool smc_pnet_match(u8 *pnetid1, u8 *pnetid2)
79 {
80 	int i;
81 
82 	for (i = 0; i < SMC_MAX_PNETID_LEN; i++) {
83 		if ((pnetid1[i] == 0 || pnetid1[i] == SMC_ASCII_BLANK) &&
84 		    (pnetid2[i] == 0 || pnetid2[i] == SMC_ASCII_BLANK))
85 			break;
86 		if (pnetid1[i] != pnetid2[i])
87 			return false;
88 	}
89 	return true;
90 }
91 
92 /* Remove a pnetid from the pnet table.
93  */
94 static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
95 {
96 	struct smc_pnetentry *pnetelem, *tmp_pe;
97 	struct smc_pnettable *pnettable;
98 	struct smc_ib_device *ibdev;
99 	struct smcd_dev *smcd_dev;
100 	struct smc_net *sn;
101 	int rc = -ENOENT;
102 	int ibport;
103 
104 	/* get pnettable for namespace */
105 	sn = net_generic(net, smc_net_id);
106 	pnettable = &sn->pnettable;
107 
108 	/* remove netdevices */
109 	write_lock(&pnettable->lock);
110 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
111 				 list) {
112 		if (!pnet_name ||
113 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
114 			list_del(&pnetelem->list);
115 			dev_put(pnetelem->ndev);
116 			kfree(pnetelem);
117 			rc = 0;
118 		}
119 	}
120 	write_unlock(&pnettable->lock);
121 
122 	/* if this is not the initial namespace, stop here */
123 	if (net != &init_net)
124 		return rc;
125 
126 	/* remove ib devices */
127 	spin_lock(&smc_ib_devices.lock);
128 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
129 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
130 			if (ibdev->pnetid_by_user[ibport] &&
131 			    (!pnet_name ||
132 			     smc_pnet_match(pnet_name,
133 					    ibdev->pnetid[ibport]))) {
134 				memset(ibdev->pnetid[ibport], 0,
135 				       SMC_MAX_PNETID_LEN);
136 				ibdev->pnetid_by_user[ibport] = false;
137 				rc = 0;
138 			}
139 		}
140 	}
141 	spin_unlock(&smc_ib_devices.lock);
142 	/* remove smcd devices */
143 	spin_lock(&smcd_dev_list.lock);
144 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
145 		if (smcd_dev->pnetid_by_user &&
146 		    (!pnet_name ||
147 		     smc_pnet_match(pnet_name, smcd_dev->pnetid))) {
148 			memset(smcd_dev->pnetid, 0, SMC_MAX_PNETID_LEN);
149 			smcd_dev->pnetid_by_user = false;
150 			rc = 0;
151 		}
152 	}
153 	spin_unlock(&smcd_dev_list.lock);
154 	return rc;
155 }
156 
157 /* Remove a pnet entry mentioning a given network device from the pnet table.
158  */
159 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
160 {
161 	struct smc_pnetentry *pnetelem, *tmp_pe;
162 	struct smc_pnettable *pnettable;
163 	struct net *net = dev_net(ndev);
164 	struct smc_net *sn;
165 	int rc = -ENOENT;
166 
167 	/* get pnettable for namespace */
168 	sn = net_generic(net, smc_net_id);
169 	pnettable = &sn->pnettable;
170 
171 	write_lock(&pnettable->lock);
172 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
173 		if (pnetelem->ndev == ndev) {
174 			list_del(&pnetelem->list);
175 			dev_put(pnetelem->ndev);
176 			kfree(pnetelem);
177 			rc = 0;
178 			break;
179 		}
180 	}
181 	write_unlock(&pnettable->lock);
182 	return rc;
183 }
184 
185 /* Append a pnetid to the end of the pnet table if not already on this list.
186  */
187 static int smc_pnet_enter(struct smc_pnettable *pnettable,
188 			  struct smc_user_pnetentry *new_pnetelem)
189 {
190 	u8 pnet_null[SMC_MAX_PNETID_LEN] = {0};
191 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
192 	struct smc_pnetentry *tmp_pnetelem;
193 	struct smc_pnetentry *pnetelem;
194 	bool new_smcddev = false;
195 	struct net_device *ndev;
196 	bool new_netdev = true;
197 	bool new_ibdev = false;
198 
199 	if (new_pnetelem->smcibdev) {
200 		struct smc_ib_device *ib_dev = new_pnetelem->smcibdev;
201 		int ib_port = new_pnetelem->ib_port;
202 
203 		spin_lock(&smc_ib_devices.lock);
204 		if (smc_pnet_match(ib_dev->pnetid[ib_port - 1], pnet_null)) {
205 			memcpy(ib_dev->pnetid[ib_port - 1],
206 			       new_pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
207 			ib_dev->pnetid_by_user[ib_port - 1] = true;
208 			new_ibdev = true;
209 		}
210 		spin_unlock(&smc_ib_devices.lock);
211 	}
212 	if (new_pnetelem->smcd_dev) {
213 		struct smcd_dev *smcd_dev = new_pnetelem->smcd_dev;
214 
215 		spin_lock(&smcd_dev_list.lock);
216 		if (smc_pnet_match(smcd_dev->pnetid, pnet_null)) {
217 			memcpy(smcd_dev->pnetid, new_pnetelem->pnet_name,
218 			       SMC_MAX_PNETID_LEN);
219 			smcd_dev->pnetid_by_user = true;
220 			new_smcddev = true;
221 		}
222 		spin_unlock(&smcd_dev_list.lock);
223 	}
224 
225 	if (!new_pnetelem->ndev)
226 		return (new_ibdev || new_smcddev) ? 0 : -EEXIST;
227 
228 	/* check if (base) netdev already has a pnetid. If there is one, we do
229 	 * not want to add a pnet table entry
230 	 */
231 	ndev = pnet_find_base_ndev(new_pnetelem->ndev);
232 	if (!smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
233 				    ndev_pnetid))
234 		return (new_ibdev || new_smcddev) ? 0 : -EEXIST;
235 
236 	/* add a new netdev entry to the pnet table if there isn't one */
237 	tmp_pnetelem = kzalloc(sizeof(*pnetelem), GFP_KERNEL);
238 	if (!tmp_pnetelem)
239 		return -ENOMEM;
240 	memcpy(tmp_pnetelem->pnet_name, new_pnetelem->pnet_name,
241 	       SMC_MAX_PNETID_LEN);
242 	tmp_pnetelem->ndev = new_pnetelem->ndev;
243 
244 	write_lock(&pnettable->lock);
245 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
246 		if (pnetelem->ndev == new_pnetelem->ndev)
247 			new_netdev = false;
248 	}
249 	if (new_netdev) {
250 		dev_hold(tmp_pnetelem->ndev);
251 		list_add_tail(&tmp_pnetelem->list, &pnettable->pnetlist);
252 		write_unlock(&pnettable->lock);
253 	} else {
254 		write_unlock(&pnettable->lock);
255 		kfree(tmp_pnetelem);
256 	}
257 
258 	return (new_netdev || new_ibdev || new_smcddev) ? 0 : -EEXIST;
259 }
260 
261 /* The limit for pnetid is 16 characters.
262  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
263  * Lower case letters are converted to upper case.
264  * Interior blanks should not be used.
265  */
266 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
267 {
268 	char *bf = skip_spaces(pnet_name);
269 	size_t len = strlen(bf);
270 	char *end = bf + len;
271 
272 	if (!len)
273 		return false;
274 	while (--end >= bf && isspace(*end))
275 		;
276 	if (end - bf >= SMC_MAX_PNETID_LEN)
277 		return false;
278 	while (bf <= end) {
279 		if (!isalnum(*bf))
280 			return false;
281 		*pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
282 		bf++;
283 	}
284 	*pnetid = '\0';
285 	return true;
286 }
287 
288 /* Find an infiniband device by a given name. The device might not exist. */
289 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
290 {
291 	struct smc_ib_device *ibdev;
292 
293 	spin_lock(&smc_ib_devices.lock);
294 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
295 		if (!strncmp(ibdev->ibdev->name, ib_name,
296 			     sizeof(ibdev->ibdev->name)) ||
297 		    !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name,
298 			     IB_DEVICE_NAME_MAX - 1)) {
299 			goto out;
300 		}
301 	}
302 	ibdev = NULL;
303 out:
304 	spin_unlock(&smc_ib_devices.lock);
305 	return ibdev;
306 }
307 
308 /* Find an smcd device by a given name. The device might not exist. */
309 static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
310 {
311 	struct smcd_dev *smcd_dev;
312 
313 	spin_lock(&smcd_dev_list.lock);
314 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
315 		if (!strncmp(dev_name(&smcd_dev->dev), smcd_name,
316 			     IB_DEVICE_NAME_MAX - 1))
317 			goto out;
318 	}
319 	smcd_dev = NULL;
320 out:
321 	spin_unlock(&smcd_dev_list.lock);
322 	return smcd_dev;
323 }
324 
325 /* Parse the supplied netlink attributes and fill a pnetentry structure.
326  * For ethernet and infiniband device names verify that the devices exist.
327  */
328 static int smc_pnet_fill_entry(struct net *net,
329 			       struct smc_user_pnetentry *pnetelem,
330 			       struct nlattr *tb[])
331 {
332 	char *string, *ibname;
333 	int rc;
334 
335 	memset(pnetelem, 0, sizeof(*pnetelem));
336 	INIT_LIST_HEAD(&pnetelem->list);
337 
338 	rc = -EINVAL;
339 	if (!tb[SMC_PNETID_NAME])
340 		goto error;
341 	string = (char *)nla_data(tb[SMC_PNETID_NAME]);
342 	if (!smc_pnetid_valid(string, pnetelem->pnet_name))
343 		goto error;
344 
345 	rc = -EINVAL;
346 	if (tb[SMC_PNETID_ETHNAME]) {
347 		string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
348 		pnetelem->ndev = dev_get_by_name(net, string);
349 		if (!pnetelem->ndev)
350 			goto error;
351 	}
352 
353 	/* if this is not the initial namespace, stop here */
354 	if (net != &init_net)
355 		return 0;
356 
357 	rc = -EINVAL;
358 	if (tb[SMC_PNETID_IBNAME]) {
359 		ibname = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
360 		ibname = strim(ibname);
361 		pnetelem->smcibdev = smc_pnet_find_ib(ibname);
362 		pnetelem->smcd_dev = smc_pnet_find_smcd(ibname);
363 		if (!pnetelem->smcibdev && !pnetelem->smcd_dev)
364 			goto error;
365 		if (pnetelem->smcibdev) {
366 			if (!tb[SMC_PNETID_IBPORT])
367 				goto error;
368 			pnetelem->ib_port = nla_get_u8(tb[SMC_PNETID_IBPORT]);
369 			if (pnetelem->ib_port < 1 ||
370 			    pnetelem->ib_port > SMC_MAX_PORTS)
371 				goto error;
372 		}
373 	}
374 
375 	return 0;
376 
377 error:
378 	if (pnetelem->ndev)
379 		dev_put(pnetelem->ndev);
380 	return rc;
381 }
382 
383 /* Convert an smc_pnetentry to a netlink attribute sequence */
384 static int smc_pnet_set_nla(struct sk_buff *msg,
385 			    struct smc_user_pnetentry *pnetelem)
386 {
387 	if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name))
388 		return -1;
389 	if (pnetelem->ndev) {
390 		if (nla_put_string(msg, SMC_PNETID_ETHNAME,
391 				   pnetelem->ndev->name))
392 			return -1;
393 	} else {
394 		if (nla_put_string(msg, SMC_PNETID_ETHNAME, "n/a"))
395 			return -1;
396 	}
397 	if (pnetelem->smcibdev) {
398 		if (nla_put_string(msg, SMC_PNETID_IBNAME,
399 			dev_name(pnetelem->smcibdev->ibdev->dev.parent)) ||
400 		    nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
401 			return -1;
402 	} else if (pnetelem->smcd_dev) {
403 		if (nla_put_string(msg, SMC_PNETID_IBNAME,
404 				   dev_name(&pnetelem->smcd_dev->dev)) ||
405 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 1))
406 			return -1;
407 	} else {
408 		if (nla_put_string(msg, SMC_PNETID_IBNAME, "n/a") ||
409 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 0xff))
410 			return -1;
411 	}
412 
413 	return 0;
414 }
415 
416 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
417 {
418 	struct net *net = genl_info_net(info);
419 	struct smc_user_pnetentry pnetelem;
420 	struct smc_pnettable *pnettable;
421 	struct smc_net *sn;
422 	int rc;
423 
424 	/* get pnettable for namespace */
425 	sn = net_generic(net, smc_net_id);
426 	pnettable = &sn->pnettable;
427 
428 	rc = smc_pnet_fill_entry(net, &pnetelem, info->attrs);
429 	if (!rc)
430 		rc = smc_pnet_enter(pnettable, &pnetelem);
431 	if (pnetelem.ndev)
432 		dev_put(pnetelem.ndev);
433 	return rc;
434 }
435 
436 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
437 {
438 	struct net *net = genl_info_net(info);
439 
440 	if (!info->attrs[SMC_PNETID_NAME])
441 		return -EINVAL;
442 	return smc_pnet_remove_by_pnetid(net,
443 				(char *)nla_data(info->attrs[SMC_PNETID_NAME]));
444 }
445 
446 static int smc_pnet_dump_start(struct netlink_callback *cb)
447 {
448 	cb->args[0] = 0;
449 	return 0;
450 }
451 
452 static int smc_pnet_dumpinfo(struct sk_buff *skb,
453 			     u32 portid, u32 seq, u32 flags,
454 			     struct smc_user_pnetentry *pnetelem)
455 {
456 	void *hdr;
457 
458 	hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
459 			  flags, SMC_PNETID_GET);
460 	if (!hdr)
461 		return -ENOMEM;
462 	if (smc_pnet_set_nla(skb, pnetelem) < 0) {
463 		genlmsg_cancel(skb, hdr);
464 		return -EMSGSIZE;
465 	}
466 	genlmsg_end(skb, hdr);
467 	return 0;
468 }
469 
470 static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
471 			  u32 seq, u8 *pnetid, int start_idx)
472 {
473 	struct smc_user_pnetentry tmp_entry;
474 	struct smc_pnettable *pnettable;
475 	struct smc_pnetentry *pnetelem;
476 	struct smc_ib_device *ibdev;
477 	struct smcd_dev *smcd_dev;
478 	struct smc_net *sn;
479 	int idx = 0;
480 	int ibport;
481 
482 	/* get pnettable for namespace */
483 	sn = net_generic(net, smc_net_id);
484 	pnettable = &sn->pnettable;
485 
486 	/* dump netdevices */
487 	read_lock(&pnettable->lock);
488 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
489 		if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
490 			continue;
491 		if (idx++ < start_idx)
492 			continue;
493 		memset(&tmp_entry, 0, sizeof(tmp_entry));
494 		memcpy(&tmp_entry.pnet_name, pnetelem->pnet_name,
495 		       SMC_MAX_PNETID_LEN);
496 		tmp_entry.ndev = pnetelem->ndev;
497 		if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
498 				      &tmp_entry)) {
499 			--idx;
500 			break;
501 		}
502 	}
503 	read_unlock(&pnettable->lock);
504 
505 	/* if this is not the initial namespace, stop here */
506 	if (net != &init_net)
507 		return idx;
508 
509 	/* dump ib devices */
510 	spin_lock(&smc_ib_devices.lock);
511 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
512 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
513 			if (ibdev->pnetid_by_user[ibport]) {
514 				if (pnetid &&
515 				    !smc_pnet_match(ibdev->pnetid[ibport],
516 						    pnetid))
517 					continue;
518 				if (idx++ < start_idx)
519 					continue;
520 				memset(&tmp_entry, 0, sizeof(tmp_entry));
521 				memcpy(&tmp_entry.pnet_name,
522 				       ibdev->pnetid[ibport],
523 				       SMC_MAX_PNETID_LEN);
524 				tmp_entry.smcibdev = ibdev;
525 				tmp_entry.ib_port = ibport + 1;
526 				if (smc_pnet_dumpinfo(skb, portid, seq,
527 						      NLM_F_MULTI,
528 						      &tmp_entry)) {
529 					--idx;
530 					break;
531 				}
532 			}
533 		}
534 	}
535 	spin_unlock(&smc_ib_devices.lock);
536 
537 	/* dump smcd devices */
538 	spin_lock(&smcd_dev_list.lock);
539 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
540 		if (smcd_dev->pnetid_by_user) {
541 			if (pnetid && !smc_pnet_match(smcd_dev->pnetid, pnetid))
542 				continue;
543 			if (idx++ < start_idx)
544 				continue;
545 			memset(&tmp_entry, 0, sizeof(tmp_entry));
546 			memcpy(&tmp_entry.pnet_name, smcd_dev->pnetid,
547 			       SMC_MAX_PNETID_LEN);
548 			tmp_entry.smcd_dev = smcd_dev;
549 			if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
550 					      &tmp_entry)) {
551 				--idx;
552 				break;
553 			}
554 		}
555 	}
556 	spin_unlock(&smcd_dev_list.lock);
557 
558 	return idx;
559 }
560 
561 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
562 {
563 	struct net *net = sock_net(skb->sk);
564 	int idx;
565 
566 	idx = _smc_pnet_dump(net, skb, NETLINK_CB(cb->skb).portid,
567 			     cb->nlh->nlmsg_seq, NULL, cb->args[0]);
568 
569 	cb->args[0] = idx;
570 	return skb->len;
571 }
572 
573 /* Retrieve one PNETID entry */
574 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
575 {
576 	struct net *net = genl_info_net(info);
577 	struct sk_buff *msg;
578 	void *hdr;
579 
580 	if (!info->attrs[SMC_PNETID_NAME])
581 		return -EINVAL;
582 
583 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
584 	if (!msg)
585 		return -ENOMEM;
586 
587 	_smc_pnet_dump(net, msg, info->snd_portid, info->snd_seq,
588 		       nla_data(info->attrs[SMC_PNETID_NAME]), 0);
589 
590 	/* finish multi part message and send it */
591 	hdr = nlmsg_put(msg, info->snd_portid, info->snd_seq, NLMSG_DONE, 0,
592 			NLM_F_MULTI);
593 	if (!hdr) {
594 		nlmsg_free(msg);
595 		return -EMSGSIZE;
596 	}
597 	return genlmsg_reply(msg, info);
598 }
599 
600 /* Remove and delete all pnetids from pnet table.
601  */
602 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
603 {
604 	struct net *net = genl_info_net(info);
605 
606 	return smc_pnet_remove_by_pnetid(net, NULL);
607 }
608 
609 /* SMC_PNETID generic netlink operation definition */
610 static const struct genl_ops smc_pnet_ops[] = {
611 	{
612 		.cmd = SMC_PNETID_GET,
613 		.flags = GENL_ADMIN_PERM,
614 		.policy = smc_pnet_policy,
615 		.doit = smc_pnet_get,
616 		.dumpit = smc_pnet_dump,
617 		.start = smc_pnet_dump_start
618 	},
619 	{
620 		.cmd = SMC_PNETID_ADD,
621 		.flags = GENL_ADMIN_PERM,
622 		.policy = smc_pnet_policy,
623 		.doit = smc_pnet_add
624 	},
625 	{
626 		.cmd = SMC_PNETID_DEL,
627 		.flags = GENL_ADMIN_PERM,
628 		.policy = smc_pnet_policy,
629 		.doit = smc_pnet_del
630 	},
631 	{
632 		.cmd = SMC_PNETID_FLUSH,
633 		.flags = GENL_ADMIN_PERM,
634 		.policy = smc_pnet_policy,
635 		.doit = smc_pnet_flush
636 	}
637 };
638 
639 /* SMC_PNETID family definition */
640 static struct genl_family smc_pnet_nl_family __ro_after_init = {
641 	.hdrsize = 0,
642 	.name = SMCR_GENL_FAMILY_NAME,
643 	.version = SMCR_GENL_FAMILY_VERSION,
644 	.maxattr = SMC_PNETID_MAX,
645 	.netnsok = true,
646 	.module = THIS_MODULE,
647 	.ops = smc_pnet_ops,
648 	.n_ops =  ARRAY_SIZE(smc_pnet_ops)
649 };
650 
651 static int smc_pnet_netdev_event(struct notifier_block *this,
652 				 unsigned long event, void *ptr)
653 {
654 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
655 
656 	switch (event) {
657 	case NETDEV_REBOOT:
658 	case NETDEV_UNREGISTER:
659 		smc_pnet_remove_by_ndev(event_dev);
660 		return NOTIFY_OK;
661 	default:
662 		return NOTIFY_DONE;
663 	}
664 }
665 
666 static struct notifier_block smc_netdev_notifier = {
667 	.notifier_call = smc_pnet_netdev_event
668 };
669 
670 /* init network namespace */
671 int smc_pnet_net_init(struct net *net)
672 {
673 	struct smc_net *sn = net_generic(net, smc_net_id);
674 	struct smc_pnettable *pnettable = &sn->pnettable;
675 
676 	INIT_LIST_HEAD(&pnettable->pnetlist);
677 	rwlock_init(&pnettable->lock);
678 
679 	return 0;
680 }
681 
682 int __init smc_pnet_init(void)
683 {
684 	int rc;
685 
686 	rc = genl_register_family(&smc_pnet_nl_family);
687 	if (rc)
688 		return rc;
689 	rc = register_netdevice_notifier(&smc_netdev_notifier);
690 	if (rc)
691 		genl_unregister_family(&smc_pnet_nl_family);
692 	return rc;
693 }
694 
695 /* exit network namespace */
696 void smc_pnet_net_exit(struct net *net)
697 {
698 	/* flush pnet table */
699 	smc_pnet_remove_by_pnetid(net, NULL);
700 }
701 
702 void smc_pnet_exit(void)
703 {
704 	unregister_netdevice_notifier(&smc_netdev_notifier);
705 	genl_unregister_family(&smc_pnet_nl_family);
706 }
707 
708 /* Determine one base device for stacked net devices.
709  * If the lower device level contains more than one devices
710  * (for instance with bonding slaves), just the first device
711  * is used to reach a base device.
712  */
713 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
714 {
715 	int i, nest_lvl;
716 
717 	rtnl_lock();
718 	nest_lvl = dev_get_nest_level(ndev);
719 	for (i = 0; i < nest_lvl; i++) {
720 		struct list_head *lower = &ndev->adj_list.lower;
721 
722 		if (list_empty(lower))
723 			break;
724 		lower = lower->next;
725 		ndev = netdev_lower_get_next(ndev, &lower);
726 	}
727 	rtnl_unlock();
728 	return ndev;
729 }
730 
731 static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
732 					      u8 *pnetid)
733 {
734 	struct smc_pnettable *pnettable;
735 	struct net *net = dev_net(ndev);
736 	struct smc_pnetentry *pnetelem;
737 	struct smc_net *sn;
738 	int rc = -ENOENT;
739 
740 	/* get pnettable for namespace */
741 	sn = net_generic(net, smc_net_id);
742 	pnettable = &sn->pnettable;
743 
744 	read_lock(&pnettable->lock);
745 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
746 		if (ndev == pnetelem->ndev) {
747 			/* get pnetid of netdev device */
748 			memcpy(pnetid, pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
749 			rc = 0;
750 			break;
751 		}
752 	}
753 	read_unlock(&pnettable->lock);
754 	return rc;
755 }
756 
757 /* if handshake network device belongs to a roce device, return its
758  * IB device and port
759  */
760 static void smc_pnet_find_rdma_dev(struct net_device *netdev,
761 				   struct smc_ib_device **smcibdev,
762 				   u8 *ibport, unsigned short vlan_id, u8 gid[])
763 {
764 	struct smc_ib_device *ibdev;
765 
766 	spin_lock(&smc_ib_devices.lock);
767 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
768 		struct net_device *ndev;
769 		int i;
770 
771 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
772 			if (!rdma_is_port_valid(ibdev->ibdev, i))
773 				continue;
774 			if (!ibdev->ibdev->ops.get_netdev)
775 				continue;
776 			ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
777 			if (!ndev)
778 				continue;
779 			dev_put(ndev);
780 			if (netdev == ndev &&
781 			    smc_ib_port_active(ibdev, i) &&
782 			    !smc_ib_determine_gid(ibdev, i, vlan_id, gid,
783 						  NULL)) {
784 				*smcibdev = ibdev;
785 				*ibport = i;
786 				break;
787 			}
788 		}
789 	}
790 	spin_unlock(&smc_ib_devices.lock);
791 }
792 
793 /* Determine the corresponding IB device port based on the hardware PNETID.
794  * Searching stops at the first matching active IB device port with vlan_id
795  * configured.
796  * If nothing found, check pnetid table.
797  * If nothing found, try to use handshake device
798  */
799 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
800 					 struct smc_ib_device **smcibdev,
801 					 u8 *ibport, unsigned short vlan_id,
802 					 u8 gid[])
803 {
804 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
805 	struct smc_ib_device *ibdev;
806 	int i;
807 
808 	ndev = pnet_find_base_ndev(ndev);
809 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
810 				   ndev_pnetid) &&
811 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
812 		smc_pnet_find_rdma_dev(ndev, smcibdev, ibport, vlan_id, gid);
813 		return; /* pnetid could not be determined */
814 	}
815 
816 	spin_lock(&smc_ib_devices.lock);
817 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
818 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
819 			if (!rdma_is_port_valid(ibdev->ibdev, i))
820 				continue;
821 			if (smc_pnet_match(ibdev->pnetid[i - 1], ndev_pnetid) &&
822 			    smc_ib_port_active(ibdev, i) &&
823 			    !smc_ib_determine_gid(ibdev, i, vlan_id, gid,
824 						  NULL))  {
825 				*smcibdev = ibdev;
826 				*ibport = i;
827 				goto out;
828 			}
829 		}
830 	}
831 out:
832 	spin_unlock(&smc_ib_devices.lock);
833 }
834 
835 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
836 					struct smcd_dev **smcismdev)
837 {
838 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
839 	struct smcd_dev *ismdev;
840 
841 	ndev = pnet_find_base_ndev(ndev);
842 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
843 				   ndev_pnetid) &&
844 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
845 		return; /* pnetid could not be determined */
846 
847 	spin_lock(&smcd_dev_list.lock);
848 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
849 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid)) {
850 			*smcismdev = ismdev;
851 			break;
852 		}
853 	}
854 	spin_unlock(&smcd_dev_list.lock);
855 }
856 
857 /* PNET table analysis for a given sock:
858  * determine ib_device and port belonging to used internal TCP socket
859  * ethernet interface.
860  */
861 void smc_pnet_find_roce_resource(struct sock *sk,
862 				 struct smc_ib_device **smcibdev, u8 *ibport,
863 				 unsigned short vlan_id, u8 gid[])
864 {
865 	struct dst_entry *dst = sk_dst_get(sk);
866 
867 	*smcibdev = NULL;
868 	*ibport = 0;
869 
870 	if (!dst)
871 		goto out;
872 	if (!dst->dev)
873 		goto out_rel;
874 
875 	smc_pnet_find_roce_by_pnetid(dst->dev, smcibdev, ibport, vlan_id, gid);
876 
877 out_rel:
878 	dst_release(dst);
879 out:
880 	return;
881 }
882 
883 void smc_pnet_find_ism_resource(struct sock *sk, struct smcd_dev **smcismdev)
884 {
885 	struct dst_entry *dst = sk_dst_get(sk);
886 
887 	*smcismdev = NULL;
888 	if (!dst)
889 		goto out;
890 	if (!dst->dev)
891 		goto out_rel;
892 
893 	smc_pnet_find_ism_by_pnetid(dst->dev, smcismdev);
894 
895 out_rel:
896 	dst_release(dst);
897 out:
898 	return;
899 }
900