xref: /linux/net/smc/smc_pnet.c (revision 4cf1bc1f10452065a29d576fc5693fc4fab5b919)
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 <linux/mutex.h>
16 #include <net/netlink.h>
17 #include <net/genetlink.h>
18 
19 #include <uapi/linux/if.h>
20 #include <uapi/linux/smc.h>
21 
22 #include <rdma/ib_verbs.h>
23 
24 #include <net/netns/generic.h>
25 #include "smc_netns.h"
26 
27 #include "smc_pnet.h"
28 #include "smc_ib.h"
29 #include "smc_ism.h"
30 #include "smc_core.h"
31 
32 static struct net_device *__pnet_find_base_ndev(struct net_device *ndev);
33 static struct net_device *pnet_find_base_ndev(struct net_device *ndev);
34 
35 static const 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 enum smc_pnet_nametype {
54 	SMC_PNET_ETH	= 1,
55 	SMC_PNET_IB	= 2,
56 };
57 
58 /* pnet entry stored in pnet table */
59 struct smc_pnetentry {
60 	struct list_head list;
61 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
62 	enum smc_pnet_nametype type;
63 	union {
64 		struct {
65 			char eth_name[IFNAMSIZ + 1];
66 			struct net_device *ndev;
67 		};
68 		struct {
69 			char ib_name[IB_DEVICE_NAME_MAX + 1];
70 			u8 ib_port;
71 		};
72 	};
73 };
74 
75 /* Check if the pnetid is set */
76 bool smc_pnet_is_pnetid_set(u8 *pnetid)
77 {
78 	if (pnetid[0] == 0 || pnetid[0] == _S)
79 		return false;
80 	return true;
81 }
82 
83 /* Check if two given pnetids match */
84 static bool smc_pnet_match(u8 *pnetid1, u8 *pnetid2)
85 {
86 	int i;
87 
88 	for (i = 0; i < SMC_MAX_PNETID_LEN; i++) {
89 		if ((pnetid1[i] == 0 || pnetid1[i] == _S) &&
90 		    (pnetid2[i] == 0 || pnetid2[i] == _S))
91 			break;
92 		if (pnetid1[i] != pnetid2[i])
93 			return false;
94 	}
95 	return true;
96 }
97 
98 /* Remove a pnetid from the pnet table.
99  */
100 static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
101 {
102 	struct smc_pnetentry *pnetelem, *tmp_pe;
103 	struct smc_pnettable *pnettable;
104 	struct smc_ib_device *ibdev;
105 	struct smcd_dev *smcd_dev;
106 	struct smc_net *sn;
107 	int rc = -ENOENT;
108 	int ibport;
109 
110 	/* get pnettable for namespace */
111 	sn = net_generic(net, smc_net_id);
112 	pnettable = &sn->pnettable;
113 
114 	/* remove table entry */
115 	write_lock(&pnettable->lock);
116 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
117 				 list) {
118 		if (!pnet_name ||
119 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
120 			list_del(&pnetelem->list);
121 			if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev) {
122 				dev_put(pnetelem->ndev);
123 				pr_warn_ratelimited("smc: net device %s "
124 						    "erased user defined "
125 						    "pnetid %.16s\n",
126 						    pnetelem->eth_name,
127 						    pnetelem->pnet_name);
128 			}
129 			kfree(pnetelem);
130 			rc = 0;
131 		}
132 	}
133 	write_unlock(&pnettable->lock);
134 
135 	/* if this is not the initial namespace, stop here */
136 	if (net != &init_net)
137 		return rc;
138 
139 	/* remove ib devices */
140 	mutex_lock(&smc_ib_devices.mutex);
141 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
142 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
143 			if (ibdev->pnetid_by_user[ibport] &&
144 			    (!pnet_name ||
145 			     smc_pnet_match(pnet_name,
146 					    ibdev->pnetid[ibport]))) {
147 				pr_warn_ratelimited("smc: ib device %s ibport "
148 						    "%d erased user defined "
149 						    "pnetid %.16s\n",
150 						    ibdev->ibdev->name,
151 						    ibport + 1,
152 						    ibdev->pnetid[ibport]);
153 				memset(ibdev->pnetid[ibport], 0,
154 				       SMC_MAX_PNETID_LEN);
155 				ibdev->pnetid_by_user[ibport] = false;
156 				rc = 0;
157 			}
158 		}
159 	}
160 	mutex_unlock(&smc_ib_devices.mutex);
161 	/* remove smcd devices */
162 	mutex_lock(&smcd_dev_list.mutex);
163 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
164 		if (smcd_dev->pnetid_by_user &&
165 		    (!pnet_name ||
166 		     smc_pnet_match(pnet_name, smcd_dev->pnetid))) {
167 			pr_warn_ratelimited("smc: smcd device %s "
168 					    "erased user defined pnetid "
169 					    "%.16s\n", dev_name(&smcd_dev->dev),
170 					    smcd_dev->pnetid);
171 			memset(smcd_dev->pnetid, 0, SMC_MAX_PNETID_LEN);
172 			smcd_dev->pnetid_by_user = false;
173 			rc = 0;
174 		}
175 	}
176 	mutex_unlock(&smcd_dev_list.mutex);
177 	return rc;
178 }
179 
180 /* Add the reference to a given network device to the pnet table.
181  */
182 static int smc_pnet_add_by_ndev(struct net_device *ndev)
183 {
184 	struct smc_pnetentry *pnetelem, *tmp_pe;
185 	struct smc_pnettable *pnettable;
186 	struct net *net = dev_net(ndev);
187 	struct smc_net *sn;
188 	int rc = -ENOENT;
189 
190 	/* get pnettable for namespace */
191 	sn = net_generic(net, smc_net_id);
192 	pnettable = &sn->pnettable;
193 
194 	write_lock(&pnettable->lock);
195 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
196 		if (pnetelem->type == SMC_PNET_ETH && !pnetelem->ndev &&
197 		    !strncmp(pnetelem->eth_name, ndev->name, IFNAMSIZ)) {
198 			dev_hold(ndev);
199 			pnetelem->ndev = ndev;
200 			rc = 0;
201 			pr_warn_ratelimited("smc: adding net device %s with "
202 					    "user defined pnetid %.16s\n",
203 					    pnetelem->eth_name,
204 					    pnetelem->pnet_name);
205 			break;
206 		}
207 	}
208 	write_unlock(&pnettable->lock);
209 	return rc;
210 }
211 
212 /* Remove the reference to a given network device from the pnet table.
213  */
214 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
215 {
216 	struct smc_pnetentry *pnetelem, *tmp_pe;
217 	struct smc_pnettable *pnettable;
218 	struct net *net = dev_net(ndev);
219 	struct smc_net *sn;
220 	int rc = -ENOENT;
221 
222 	/* get pnettable for namespace */
223 	sn = net_generic(net, smc_net_id);
224 	pnettable = &sn->pnettable;
225 
226 	write_lock(&pnettable->lock);
227 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
228 		if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev == ndev) {
229 			dev_put(pnetelem->ndev);
230 			pnetelem->ndev = NULL;
231 			rc = 0;
232 			pr_warn_ratelimited("smc: removing net device %s with "
233 					    "user defined pnetid %.16s\n",
234 					    pnetelem->eth_name,
235 					    pnetelem->pnet_name);
236 			break;
237 		}
238 	}
239 	write_unlock(&pnettable->lock);
240 	return rc;
241 }
242 
243 /* Apply pnetid to ib device when no pnetid is set.
244  */
245 static bool smc_pnet_apply_ib(struct smc_ib_device *ib_dev, u8 ib_port,
246 			      char *pnet_name)
247 {
248 	bool applied = false;
249 
250 	mutex_lock(&smc_ib_devices.mutex);
251 	if (!smc_pnet_is_pnetid_set(ib_dev->pnetid[ib_port - 1])) {
252 		memcpy(ib_dev->pnetid[ib_port - 1], pnet_name,
253 		       SMC_MAX_PNETID_LEN);
254 		ib_dev->pnetid_by_user[ib_port - 1] = true;
255 		applied = true;
256 	}
257 	mutex_unlock(&smc_ib_devices.mutex);
258 	return applied;
259 }
260 
261 /* Apply pnetid to smcd device when no pnetid is set.
262  */
263 static bool smc_pnet_apply_smcd(struct smcd_dev *smcd_dev, char *pnet_name)
264 {
265 	bool applied = false;
266 
267 	mutex_lock(&smcd_dev_list.mutex);
268 	if (!smc_pnet_is_pnetid_set(smcd_dev->pnetid)) {
269 		memcpy(smcd_dev->pnetid, pnet_name, SMC_MAX_PNETID_LEN);
270 		smcd_dev->pnetid_by_user = true;
271 		applied = true;
272 	}
273 	mutex_unlock(&smcd_dev_list.mutex);
274 	return applied;
275 }
276 
277 /* The limit for pnetid is 16 characters.
278  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
279  * Lower case letters are converted to upper case.
280  * Interior blanks should not be used.
281  */
282 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
283 {
284 	char *bf = skip_spaces(pnet_name);
285 	size_t len = strlen(bf);
286 	char *end = bf + len;
287 
288 	if (!len)
289 		return false;
290 	while (--end >= bf && isspace(*end))
291 		;
292 	if (end - bf >= SMC_MAX_PNETID_LEN)
293 		return false;
294 	while (bf <= end) {
295 		if (!isalnum(*bf))
296 			return false;
297 		*pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
298 		bf++;
299 	}
300 	*pnetid = '\0';
301 	return true;
302 }
303 
304 /* Find an infiniband device by a given name. The device might not exist. */
305 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
306 {
307 	struct smc_ib_device *ibdev;
308 
309 	mutex_lock(&smc_ib_devices.mutex);
310 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
311 		if (!strncmp(ibdev->ibdev->name, ib_name,
312 			     sizeof(ibdev->ibdev->name)) ||
313 		    !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name,
314 			     IB_DEVICE_NAME_MAX - 1)) {
315 			goto out;
316 		}
317 	}
318 	ibdev = NULL;
319 out:
320 	mutex_unlock(&smc_ib_devices.mutex);
321 	return ibdev;
322 }
323 
324 /* Find an smcd device by a given name. The device might not exist. */
325 static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
326 {
327 	struct smcd_dev *smcd_dev;
328 
329 	mutex_lock(&smcd_dev_list.mutex);
330 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
331 		if (!strncmp(dev_name(&smcd_dev->dev), smcd_name,
332 			     IB_DEVICE_NAME_MAX - 1))
333 			goto out;
334 	}
335 	smcd_dev = NULL;
336 out:
337 	mutex_unlock(&smcd_dev_list.mutex);
338 	return smcd_dev;
339 }
340 
341 static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
342 			    char *eth_name, char *pnet_name)
343 {
344 	struct smc_pnetentry *tmp_pe, *new_pe;
345 	struct net_device *ndev, *base_ndev;
346 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
347 	bool new_netdev;
348 	int rc;
349 
350 	/* check if (base) netdev already has a pnetid. If there is one, we do
351 	 * not want to add a pnet table entry
352 	 */
353 	rc = -EEXIST;
354 	ndev = dev_get_by_name(net, eth_name);	/* dev_hold() */
355 	if (ndev) {
356 		base_ndev = pnet_find_base_ndev(ndev);
357 		if (!smc_pnetid_by_dev_port(base_ndev->dev.parent,
358 					    base_ndev->dev_port, ndev_pnetid))
359 			goto out_put;
360 	}
361 
362 	/* add a new netdev entry to the pnet table if there isn't one */
363 	rc = -ENOMEM;
364 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
365 	if (!new_pe)
366 		goto out_put;
367 	new_pe->type = SMC_PNET_ETH;
368 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
369 	strncpy(new_pe->eth_name, eth_name, IFNAMSIZ);
370 	new_pe->ndev = ndev;
371 
372 	rc = -EEXIST;
373 	new_netdev = true;
374 	write_lock(&pnettable->lock);
375 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
376 		if (tmp_pe->type == SMC_PNET_ETH &&
377 		    !strncmp(tmp_pe->eth_name, eth_name, IFNAMSIZ)) {
378 			new_netdev = false;
379 			break;
380 		}
381 	}
382 	if (new_netdev) {
383 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
384 		write_unlock(&pnettable->lock);
385 	} else {
386 		write_unlock(&pnettable->lock);
387 		kfree(new_pe);
388 		goto out_put;
389 	}
390 	if (ndev)
391 		pr_warn_ratelimited("smc: net device %s "
392 				    "applied user defined pnetid %.16s\n",
393 				    new_pe->eth_name, new_pe->pnet_name);
394 	return 0;
395 
396 out_put:
397 	if (ndev)
398 		dev_put(ndev);
399 	return rc;
400 }
401 
402 static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
403 			   u8 ib_port, char *pnet_name)
404 {
405 	struct smc_pnetentry *tmp_pe, *new_pe;
406 	struct smc_ib_device *ib_dev;
407 	bool smcddev_applied = true;
408 	bool ibdev_applied = true;
409 	struct smcd_dev *smcd_dev;
410 	bool new_ibdev;
411 
412 	/* try to apply the pnetid to active devices */
413 	ib_dev = smc_pnet_find_ib(ib_name);
414 	if (ib_dev) {
415 		ibdev_applied = smc_pnet_apply_ib(ib_dev, ib_port, pnet_name);
416 		if (ibdev_applied)
417 			pr_warn_ratelimited("smc: ib device %s ibport %d "
418 					    "applied user defined pnetid "
419 					    "%.16s\n", ib_dev->ibdev->name,
420 					    ib_port,
421 					    ib_dev->pnetid[ib_port - 1]);
422 	}
423 	smcd_dev = smc_pnet_find_smcd(ib_name);
424 	if (smcd_dev) {
425 		smcddev_applied = smc_pnet_apply_smcd(smcd_dev, pnet_name);
426 		if (smcddev_applied)
427 			pr_warn_ratelimited("smc: smcd device %s "
428 					    "applied user defined pnetid "
429 					    "%.16s\n", dev_name(&smcd_dev->dev),
430 					    smcd_dev->pnetid);
431 	}
432 	/* Apply fails when a device has a hardware-defined pnetid set, do not
433 	 * add a pnet table entry in that case.
434 	 */
435 	if (!ibdev_applied || !smcddev_applied)
436 		return -EEXIST;
437 
438 	/* add a new ib entry to the pnet table if there isn't one */
439 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
440 	if (!new_pe)
441 		return -ENOMEM;
442 	new_pe->type = SMC_PNET_IB;
443 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
444 	strncpy(new_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX);
445 	new_pe->ib_port = ib_port;
446 
447 	new_ibdev = true;
448 	write_lock(&pnettable->lock);
449 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
450 		if (tmp_pe->type == SMC_PNET_IB &&
451 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
452 			new_ibdev = false;
453 			break;
454 		}
455 	}
456 	if (new_ibdev) {
457 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
458 		write_unlock(&pnettable->lock);
459 	} else {
460 		write_unlock(&pnettable->lock);
461 		kfree(new_pe);
462 	}
463 	return (new_ibdev) ? 0 : -EEXIST;
464 }
465 
466 /* Append a pnetid to the end of the pnet table if not already on this list.
467  */
468 static int smc_pnet_enter(struct net *net, struct nlattr *tb[])
469 {
470 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
471 	struct smc_pnettable *pnettable;
472 	bool new_netdev = false;
473 	bool new_ibdev = false;
474 	struct smc_net *sn;
475 	u8 ibport = 1;
476 	char *string;
477 	int rc;
478 
479 	/* get pnettable for namespace */
480 	sn = net_generic(net, smc_net_id);
481 	pnettable = &sn->pnettable;
482 
483 	rc = -EINVAL;
484 	if (!tb[SMC_PNETID_NAME])
485 		goto error;
486 	string = (char *)nla_data(tb[SMC_PNETID_NAME]);
487 	if (!smc_pnetid_valid(string, pnet_name))
488 		goto error;
489 
490 	if (tb[SMC_PNETID_ETHNAME]) {
491 		string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
492 		rc = smc_pnet_add_eth(pnettable, net, string, pnet_name);
493 		if (!rc)
494 			new_netdev = true;
495 		else if (rc != -EEXIST)
496 			goto error;
497 	}
498 
499 	/* if this is not the initial namespace, stop here */
500 	if (net != &init_net)
501 		return new_netdev ? 0 : -EEXIST;
502 
503 	rc = -EINVAL;
504 	if (tb[SMC_PNETID_IBNAME]) {
505 		string = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
506 		string = strim(string);
507 		if (tb[SMC_PNETID_IBPORT]) {
508 			ibport = nla_get_u8(tb[SMC_PNETID_IBPORT]);
509 			if (ibport < 1 || ibport > SMC_MAX_PORTS)
510 				goto error;
511 		}
512 		rc = smc_pnet_add_ib(pnettable, string, ibport, pnet_name);
513 		if (!rc)
514 			new_ibdev = true;
515 		else if (rc != -EEXIST)
516 			goto error;
517 	}
518 	return (new_netdev || new_ibdev) ? 0 : -EEXIST;
519 
520 error:
521 	return rc;
522 }
523 
524 /* Convert an smc_pnetentry to a netlink attribute sequence */
525 static int smc_pnet_set_nla(struct sk_buff *msg,
526 			    struct smc_pnetentry *pnetelem)
527 {
528 	if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name))
529 		return -1;
530 	if (pnetelem->type == SMC_PNET_ETH) {
531 		if (nla_put_string(msg, SMC_PNETID_ETHNAME,
532 				   pnetelem->eth_name))
533 			return -1;
534 	} else {
535 		if (nla_put_string(msg, SMC_PNETID_ETHNAME, "n/a"))
536 			return -1;
537 	}
538 	if (pnetelem->type == SMC_PNET_IB) {
539 		if (nla_put_string(msg, SMC_PNETID_IBNAME, pnetelem->ib_name) ||
540 		    nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
541 			return -1;
542 	} else {
543 		if (nla_put_string(msg, SMC_PNETID_IBNAME, "n/a") ||
544 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 0xff))
545 			return -1;
546 	}
547 
548 	return 0;
549 }
550 
551 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
552 {
553 	struct net *net = genl_info_net(info);
554 
555 	return smc_pnet_enter(net, info->attrs);
556 }
557 
558 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
559 {
560 	struct net *net = genl_info_net(info);
561 
562 	if (!info->attrs[SMC_PNETID_NAME])
563 		return -EINVAL;
564 	return smc_pnet_remove_by_pnetid(net,
565 				(char *)nla_data(info->attrs[SMC_PNETID_NAME]));
566 }
567 
568 static int smc_pnet_dump_start(struct netlink_callback *cb)
569 {
570 	cb->args[0] = 0;
571 	return 0;
572 }
573 
574 static int smc_pnet_dumpinfo(struct sk_buff *skb,
575 			     u32 portid, u32 seq, u32 flags,
576 			     struct smc_pnetentry *pnetelem)
577 {
578 	void *hdr;
579 
580 	hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
581 			  flags, SMC_PNETID_GET);
582 	if (!hdr)
583 		return -ENOMEM;
584 	if (smc_pnet_set_nla(skb, pnetelem) < 0) {
585 		genlmsg_cancel(skb, hdr);
586 		return -EMSGSIZE;
587 	}
588 	genlmsg_end(skb, hdr);
589 	return 0;
590 }
591 
592 static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
593 			  u32 seq, u8 *pnetid, int start_idx)
594 {
595 	struct smc_pnettable *pnettable;
596 	struct smc_pnetentry *pnetelem;
597 	struct smc_net *sn;
598 	int idx = 0;
599 
600 	/* get pnettable for namespace */
601 	sn = net_generic(net, smc_net_id);
602 	pnettable = &sn->pnettable;
603 
604 	/* dump pnettable entries */
605 	read_lock(&pnettable->lock);
606 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
607 		if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
608 			continue;
609 		if (idx++ < start_idx)
610 			continue;
611 		/* if this is not the initial namespace, dump only netdev */
612 		if (net != &init_net && pnetelem->type != SMC_PNET_ETH)
613 			continue;
614 		if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
615 				      pnetelem)) {
616 			--idx;
617 			break;
618 		}
619 	}
620 	read_unlock(&pnettable->lock);
621 	return idx;
622 }
623 
624 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
625 {
626 	struct net *net = sock_net(skb->sk);
627 	int idx;
628 
629 	idx = _smc_pnet_dump(net, skb, NETLINK_CB(cb->skb).portid,
630 			     cb->nlh->nlmsg_seq, NULL, cb->args[0]);
631 
632 	cb->args[0] = idx;
633 	return skb->len;
634 }
635 
636 /* Retrieve one PNETID entry */
637 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
638 {
639 	struct net *net = genl_info_net(info);
640 	struct sk_buff *msg;
641 	void *hdr;
642 
643 	if (!info->attrs[SMC_PNETID_NAME])
644 		return -EINVAL;
645 
646 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
647 	if (!msg)
648 		return -ENOMEM;
649 
650 	_smc_pnet_dump(net, msg, info->snd_portid, info->snd_seq,
651 		       nla_data(info->attrs[SMC_PNETID_NAME]), 0);
652 
653 	/* finish multi part message and send it */
654 	hdr = nlmsg_put(msg, info->snd_portid, info->snd_seq, NLMSG_DONE, 0,
655 			NLM_F_MULTI);
656 	if (!hdr) {
657 		nlmsg_free(msg);
658 		return -EMSGSIZE;
659 	}
660 	return genlmsg_reply(msg, info);
661 }
662 
663 /* Remove and delete all pnetids from pnet table.
664  */
665 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
666 {
667 	struct net *net = genl_info_net(info);
668 
669 	smc_pnet_remove_by_pnetid(net, NULL);
670 	return 0;
671 }
672 
673 /* SMC_PNETID generic netlink operation definition */
674 static const struct genl_ops smc_pnet_ops[] = {
675 	{
676 		.cmd = SMC_PNETID_GET,
677 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
678 		/* can be retrieved by unprivileged users */
679 		.doit = smc_pnet_get,
680 		.dumpit = smc_pnet_dump,
681 		.start = smc_pnet_dump_start
682 	},
683 	{
684 		.cmd = SMC_PNETID_ADD,
685 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
686 		.flags = GENL_ADMIN_PERM,
687 		.doit = smc_pnet_add
688 	},
689 	{
690 		.cmd = SMC_PNETID_DEL,
691 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
692 		.flags = GENL_ADMIN_PERM,
693 		.doit = smc_pnet_del
694 	},
695 	{
696 		.cmd = SMC_PNETID_FLUSH,
697 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
698 		.flags = GENL_ADMIN_PERM,
699 		.doit = smc_pnet_flush
700 	}
701 };
702 
703 /* SMC_PNETID family definition */
704 static struct genl_family smc_pnet_nl_family __ro_after_init = {
705 	.hdrsize = 0,
706 	.name = SMCR_GENL_FAMILY_NAME,
707 	.version = SMCR_GENL_FAMILY_VERSION,
708 	.maxattr = SMC_PNETID_MAX,
709 	.policy = smc_pnet_policy,
710 	.netnsok = true,
711 	.module = THIS_MODULE,
712 	.ops = smc_pnet_ops,
713 	.n_ops =  ARRAY_SIZE(smc_pnet_ops)
714 };
715 
716 bool smc_pnet_is_ndev_pnetid(struct net *net, u8 *pnetid)
717 {
718 	struct smc_net *sn = net_generic(net, smc_net_id);
719 	struct smc_pnetids_ndev_entry *pe;
720 	bool rc = false;
721 
722 	read_lock(&sn->pnetids_ndev.lock);
723 	list_for_each_entry(pe, &sn->pnetids_ndev.list, list) {
724 		if (smc_pnet_match(pnetid, pe->pnetid)) {
725 			rc = true;
726 			goto unlock;
727 		}
728 	}
729 
730 unlock:
731 	read_unlock(&sn->pnetids_ndev.lock);
732 	return rc;
733 }
734 
735 static int smc_pnet_add_pnetid(struct net *net, u8 *pnetid)
736 {
737 	struct smc_net *sn = net_generic(net, smc_net_id);
738 	struct smc_pnetids_ndev_entry *pe, *pi;
739 
740 	pe = kzalloc(sizeof(*pe), GFP_KERNEL);
741 	if (!pe)
742 		return -ENOMEM;
743 
744 	write_lock(&sn->pnetids_ndev.lock);
745 	list_for_each_entry(pi, &sn->pnetids_ndev.list, list) {
746 		if (smc_pnet_match(pnetid, pe->pnetid)) {
747 			refcount_inc(&pi->refcnt);
748 			kfree(pe);
749 			goto unlock;
750 		}
751 	}
752 	refcount_set(&pe->refcnt, 1);
753 	memcpy(pe->pnetid, pnetid, SMC_MAX_PNETID_LEN);
754 	list_add_tail(&pe->list, &sn->pnetids_ndev.list);
755 
756 unlock:
757 	write_unlock(&sn->pnetids_ndev.lock);
758 	return 0;
759 }
760 
761 static void smc_pnet_remove_pnetid(struct net *net, u8 *pnetid)
762 {
763 	struct smc_net *sn = net_generic(net, smc_net_id);
764 	struct smc_pnetids_ndev_entry *pe, *pe2;
765 
766 	write_lock(&sn->pnetids_ndev.lock);
767 	list_for_each_entry_safe(pe, pe2, &sn->pnetids_ndev.list, list) {
768 		if (smc_pnet_match(pnetid, pe->pnetid)) {
769 			if (refcount_dec_and_test(&pe->refcnt)) {
770 				list_del(&pe->list);
771 				kfree(pe);
772 			}
773 			break;
774 		}
775 	}
776 	write_unlock(&sn->pnetids_ndev.lock);
777 }
778 
779 static void smc_pnet_add_base_pnetid(struct net *net, struct net_device *dev,
780 				     u8 *ndev_pnetid)
781 {
782 	struct net_device *base_dev;
783 
784 	base_dev = __pnet_find_base_ndev(dev);
785 	if (base_dev->flags & IFF_UP &&
786 	    !smc_pnetid_by_dev_port(base_dev->dev.parent, base_dev->dev_port,
787 				    ndev_pnetid)) {
788 		/* add to PNETIDs list */
789 		smc_pnet_add_pnetid(net, ndev_pnetid);
790 	}
791 }
792 
793 /* create initial list of netdevice pnetids */
794 static void smc_pnet_create_pnetids_list(struct net *net)
795 {
796 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
797 	struct net_device *dev;
798 
799 	rtnl_lock();
800 	for_each_netdev(net, dev)
801 		smc_pnet_add_base_pnetid(net, dev, ndev_pnetid);
802 	rtnl_unlock();
803 }
804 
805 /* clean up list of netdevice pnetids */
806 static void smc_pnet_destroy_pnetids_list(struct net *net)
807 {
808 	struct smc_net *sn = net_generic(net, smc_net_id);
809 	struct smc_pnetids_ndev_entry *pe, *temp_pe;
810 
811 	write_lock(&sn->pnetids_ndev.lock);
812 	list_for_each_entry_safe(pe, temp_pe, &sn->pnetids_ndev.list, list) {
813 		list_del(&pe->list);
814 		kfree(pe);
815 	}
816 	write_unlock(&sn->pnetids_ndev.lock);
817 }
818 
819 static int smc_pnet_netdev_event(struct notifier_block *this,
820 				 unsigned long event, void *ptr)
821 {
822 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
823 	struct net *net = dev_net(event_dev);
824 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
825 
826 	switch (event) {
827 	case NETDEV_REBOOT:
828 	case NETDEV_UNREGISTER:
829 		smc_pnet_remove_by_ndev(event_dev);
830 		return NOTIFY_OK;
831 	case NETDEV_REGISTER:
832 		smc_pnet_add_by_ndev(event_dev);
833 		return NOTIFY_OK;
834 	case NETDEV_UP:
835 		smc_pnet_add_base_pnetid(net, event_dev, ndev_pnetid);
836 		return NOTIFY_OK;
837 	case NETDEV_DOWN:
838 		event_dev = __pnet_find_base_ndev(event_dev);
839 		if (!smc_pnetid_by_dev_port(event_dev->dev.parent,
840 					    event_dev->dev_port, ndev_pnetid)) {
841 			/* remove from PNETIDs list */
842 			smc_pnet_remove_pnetid(net, ndev_pnetid);
843 		}
844 		return NOTIFY_OK;
845 	default:
846 		return NOTIFY_DONE;
847 	}
848 }
849 
850 static struct notifier_block smc_netdev_notifier = {
851 	.notifier_call = smc_pnet_netdev_event
852 };
853 
854 /* init network namespace */
855 int smc_pnet_net_init(struct net *net)
856 {
857 	struct smc_net *sn = net_generic(net, smc_net_id);
858 	struct smc_pnettable *pnettable = &sn->pnettable;
859 	struct smc_pnetids_ndev *pnetids_ndev = &sn->pnetids_ndev;
860 
861 	INIT_LIST_HEAD(&pnettable->pnetlist);
862 	rwlock_init(&pnettable->lock);
863 	INIT_LIST_HEAD(&pnetids_ndev->list);
864 	rwlock_init(&pnetids_ndev->lock);
865 
866 	smc_pnet_create_pnetids_list(net);
867 
868 	return 0;
869 }
870 
871 int __init smc_pnet_init(void)
872 {
873 	int rc;
874 
875 	rc = genl_register_family(&smc_pnet_nl_family);
876 	if (rc)
877 		return rc;
878 	rc = register_netdevice_notifier(&smc_netdev_notifier);
879 	if (rc)
880 		genl_unregister_family(&smc_pnet_nl_family);
881 
882 	return rc;
883 }
884 
885 /* exit network namespace */
886 void smc_pnet_net_exit(struct net *net)
887 {
888 	/* flush pnet table */
889 	smc_pnet_remove_by_pnetid(net, NULL);
890 	smc_pnet_destroy_pnetids_list(net);
891 }
892 
893 void smc_pnet_exit(void)
894 {
895 	unregister_netdevice_notifier(&smc_netdev_notifier);
896 	genl_unregister_family(&smc_pnet_nl_family);
897 }
898 
899 static struct net_device *__pnet_find_base_ndev(struct net_device *ndev)
900 {
901 	int i, nest_lvl;
902 
903 	ASSERT_RTNL();
904 	nest_lvl = ndev->lower_level;
905 	for (i = 0; i < nest_lvl; i++) {
906 		struct list_head *lower = &ndev->adj_list.lower;
907 
908 		if (list_empty(lower))
909 			break;
910 		lower = lower->next;
911 		ndev = netdev_lower_get_next(ndev, &lower);
912 	}
913 	return ndev;
914 }
915 
916 /* Determine one base device for stacked net devices.
917  * If the lower device level contains more than one devices
918  * (for instance with bonding slaves), just the first device
919  * is used to reach a base device.
920  */
921 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
922 {
923 	rtnl_lock();
924 	ndev = __pnet_find_base_ndev(ndev);
925 	rtnl_unlock();
926 	return ndev;
927 }
928 
929 static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
930 					      u8 *pnetid)
931 {
932 	struct smc_pnettable *pnettable;
933 	struct net *net = dev_net(ndev);
934 	struct smc_pnetentry *pnetelem;
935 	struct smc_net *sn;
936 	int rc = -ENOENT;
937 
938 	/* get pnettable for namespace */
939 	sn = net_generic(net, smc_net_id);
940 	pnettable = &sn->pnettable;
941 
942 	read_lock(&pnettable->lock);
943 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
944 		if (pnetelem->type == SMC_PNET_ETH && ndev == pnetelem->ndev) {
945 			/* get pnetid of netdev device */
946 			memcpy(pnetid, pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
947 			rc = 0;
948 			break;
949 		}
950 	}
951 	read_unlock(&pnettable->lock);
952 	return rc;
953 }
954 
955 /* find a roce device for the given pnetid */
956 static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
957 					  struct smc_init_info *ini,
958 					  struct smc_ib_device *known_dev)
959 {
960 	struct smc_ib_device *ibdev;
961 	int i;
962 
963 	ini->ib_dev = NULL;
964 	mutex_lock(&smc_ib_devices.mutex);
965 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
966 		if (ibdev == known_dev)
967 			continue;
968 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
969 			if (!rdma_is_port_valid(ibdev->ibdev, i))
970 				continue;
971 			if (smc_pnet_match(ibdev->pnetid[i - 1], pnet_id) &&
972 			    smc_ib_port_active(ibdev, i) &&
973 			    !test_bit(i - 1, ibdev->ports_going_away) &&
974 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
975 						  ini->ib_gid, NULL)) {
976 				ini->ib_dev = ibdev;
977 				ini->ib_port = i;
978 				goto out;
979 			}
980 		}
981 	}
982 out:
983 	mutex_unlock(&smc_ib_devices.mutex);
984 }
985 
986 /* find alternate roce device with same pnet_id and vlan_id */
987 void smc_pnet_find_alt_roce(struct smc_link_group *lgr,
988 			    struct smc_init_info *ini,
989 			    struct smc_ib_device *known_dev)
990 {
991 	_smc_pnet_find_roce_by_pnetid(lgr->pnet_id, ini, known_dev);
992 }
993 
994 /* if handshake network device belongs to a roce device, return its
995  * IB device and port
996  */
997 static void smc_pnet_find_rdma_dev(struct net_device *netdev,
998 				   struct smc_init_info *ini)
999 {
1000 	struct smc_ib_device *ibdev;
1001 
1002 	mutex_lock(&smc_ib_devices.mutex);
1003 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
1004 		struct net_device *ndev;
1005 		int i;
1006 
1007 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
1008 			if (!rdma_is_port_valid(ibdev->ibdev, i))
1009 				continue;
1010 			if (!ibdev->ibdev->ops.get_netdev)
1011 				continue;
1012 			ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
1013 			if (!ndev)
1014 				continue;
1015 			dev_put(ndev);
1016 			if (netdev == ndev &&
1017 			    smc_ib_port_active(ibdev, i) &&
1018 			    !test_bit(i - 1, ibdev->ports_going_away) &&
1019 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
1020 						  ini->ib_gid, NULL)) {
1021 				ini->ib_dev = ibdev;
1022 				ini->ib_port = i;
1023 				break;
1024 			}
1025 		}
1026 	}
1027 	mutex_unlock(&smc_ib_devices.mutex);
1028 }
1029 
1030 /* Determine the corresponding IB device port based on the hardware PNETID.
1031  * Searching stops at the first matching active IB device port with vlan_id
1032  * configured.
1033  * If nothing found, check pnetid table.
1034  * If nothing found, try to use handshake device
1035  */
1036 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
1037 					 struct smc_init_info *ini)
1038 {
1039 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
1040 
1041 	ndev = pnet_find_base_ndev(ndev);
1042 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
1043 				   ndev_pnetid) &&
1044 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
1045 		smc_pnet_find_rdma_dev(ndev, ini);
1046 		return; /* pnetid could not be determined */
1047 	}
1048 	_smc_pnet_find_roce_by_pnetid(ndev_pnetid, ini, NULL);
1049 }
1050 
1051 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
1052 					struct smc_init_info *ini)
1053 {
1054 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
1055 	struct smcd_dev *ismdev;
1056 
1057 	ndev = pnet_find_base_ndev(ndev);
1058 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
1059 				   ndev_pnetid) &&
1060 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
1061 		return; /* pnetid could not be determined */
1062 
1063 	mutex_lock(&smcd_dev_list.mutex);
1064 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
1065 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid) &&
1066 		    !ismdev->going_away &&
1067 		    (!ini->ism_peer_gid[0] ||
1068 		     !smc_ism_cantalk(ini->ism_peer_gid[0], ini->vlan_id,
1069 				      ismdev))) {
1070 			ini->ism_dev[0] = ismdev;
1071 			break;
1072 		}
1073 	}
1074 	mutex_unlock(&smcd_dev_list.mutex);
1075 }
1076 
1077 /* PNET table analysis for a given sock:
1078  * determine ib_device and port belonging to used internal TCP socket
1079  * ethernet interface.
1080  */
1081 void smc_pnet_find_roce_resource(struct sock *sk, struct smc_init_info *ini)
1082 {
1083 	struct dst_entry *dst = sk_dst_get(sk);
1084 
1085 	ini->ib_dev = NULL;
1086 	ini->ib_port = 0;
1087 	if (!dst)
1088 		goto out;
1089 	if (!dst->dev)
1090 		goto out_rel;
1091 
1092 	smc_pnet_find_roce_by_pnetid(dst->dev, ini);
1093 
1094 out_rel:
1095 	dst_release(dst);
1096 out:
1097 	return;
1098 }
1099 
1100 void smc_pnet_find_ism_resource(struct sock *sk, struct smc_init_info *ini)
1101 {
1102 	struct dst_entry *dst = sk_dst_get(sk);
1103 
1104 	ini->ism_dev[0] = NULL;
1105 	if (!dst)
1106 		goto out;
1107 	if (!dst->dev)
1108 		goto out_rel;
1109 
1110 	smc_pnet_find_ism_by_pnetid(dst->dev, ini);
1111 
1112 out_rel:
1113 	dst_release(dst);
1114 out:
1115 	return;
1116 }
1117 
1118 /* Lookup and apply a pnet table entry to the given ib device.
1119  */
1120 int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
1121 {
1122 	char *ib_name = smcibdev->ibdev->name;
1123 	struct smc_pnettable *pnettable;
1124 	struct smc_pnetentry *tmp_pe;
1125 	struct smc_net *sn;
1126 	int rc = -ENOENT;
1127 
1128 	/* get pnettable for init namespace */
1129 	sn = net_generic(&init_net, smc_net_id);
1130 	pnettable = &sn->pnettable;
1131 
1132 	read_lock(&pnettable->lock);
1133 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
1134 		if (tmp_pe->type == SMC_PNET_IB &&
1135 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX) &&
1136 		    tmp_pe->ib_port == ib_port) {
1137 			smc_pnet_apply_ib(smcibdev, ib_port, tmp_pe->pnet_name);
1138 			rc = 0;
1139 			break;
1140 		}
1141 	}
1142 	read_unlock(&pnettable->lock);
1143 
1144 	return rc;
1145 }
1146 
1147 /* Lookup and apply a pnet table entry to the given smcd device.
1148  */
1149 int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
1150 {
1151 	const char *ib_name = dev_name(&smcddev->dev);
1152 	struct smc_pnettable *pnettable;
1153 	struct smc_pnetentry *tmp_pe;
1154 	struct smc_net *sn;
1155 	int rc = -ENOENT;
1156 
1157 	/* get pnettable for init namespace */
1158 	sn = net_generic(&init_net, smc_net_id);
1159 	pnettable = &sn->pnettable;
1160 
1161 	read_lock(&pnettable->lock);
1162 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
1163 		if (tmp_pe->type == SMC_PNET_IB &&
1164 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
1165 			smc_pnet_apply_smcd(smcddev, tmp_pe->pnet_name);
1166 			rc = 0;
1167 			break;
1168 		}
1169 	}
1170 	read_unlock(&pnettable->lock);
1171 
1172 	return rc;
1173 }
1174