xref: /linux/net/smc/smc_pnet.c (revision c7546e2c3cb739a3c1a2f5acaf9bb629d401afe5)
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 			netdevice_tracker dev_tracker;
68 		};
69 		struct {
70 			char ib_name[IB_DEVICE_NAME_MAX + 1];
71 			u8 ib_port;
72 		};
73 	};
74 };
75 
76 /* Check if the pnetid is set */
77 bool smc_pnet_is_pnetid_set(u8 *pnetid)
78 {
79 	if (pnetid[0] == 0 || pnetid[0] == _S)
80 		return false;
81 	return true;
82 }
83 
84 /* Check if two given pnetids match */
85 static bool smc_pnet_match(u8 *pnetid1, u8 *pnetid2)
86 {
87 	int i;
88 
89 	for (i = 0; i < SMC_MAX_PNETID_LEN; i++) {
90 		if ((pnetid1[i] == 0 || pnetid1[i] == _S) &&
91 		    (pnetid2[i] == 0 || pnetid2[i] == _S))
92 			break;
93 		if (pnetid1[i] != pnetid2[i])
94 			return false;
95 	}
96 	return true;
97 }
98 
99 /* Remove a pnetid from the pnet table.
100  */
101 static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
102 {
103 	struct smc_pnetentry *pnetelem, *tmp_pe;
104 	struct smc_pnettable *pnettable;
105 	struct smc_ib_device *ibdev;
106 	struct smcd_dev *smcd;
107 	struct smc_net *sn;
108 	int rc = -ENOENT;
109 	int ibport;
110 
111 	/* get pnettable for namespace */
112 	sn = net_generic(net, smc_net_id);
113 	pnettable = &sn->pnettable;
114 
115 	/* remove table entry */
116 	mutex_lock(&pnettable->lock);
117 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
118 				 list) {
119 		if (!pnet_name ||
120 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
121 			list_del(&pnetelem->list);
122 			if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev) {
123 				netdev_put(pnetelem->ndev,
124 					   &pnetelem->dev_tracker);
125 				pr_warn_ratelimited("smc: net device %s "
126 						    "erased user defined "
127 						    "pnetid %.16s\n",
128 						    pnetelem->eth_name,
129 						    pnetelem->pnet_name);
130 			}
131 			kfree(pnetelem);
132 			rc = 0;
133 		}
134 	}
135 	mutex_unlock(&pnettable->lock);
136 
137 	/* if this is not the initial namespace, stop here */
138 	if (net != &init_net)
139 		return rc;
140 
141 	/* remove ib devices */
142 	mutex_lock(&smc_ib_devices.mutex);
143 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
144 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
145 			if (ibdev->pnetid_by_user[ibport] &&
146 			    (!pnet_name ||
147 			     smc_pnet_match(pnet_name,
148 					    ibdev->pnetid[ibport]))) {
149 				pr_warn_ratelimited("smc: ib device %s ibport "
150 						    "%d erased user defined "
151 						    "pnetid %.16s\n",
152 						    ibdev->ibdev->name,
153 						    ibport + 1,
154 						    ibdev->pnetid[ibport]);
155 				memset(ibdev->pnetid[ibport], 0,
156 				       SMC_MAX_PNETID_LEN);
157 				ibdev->pnetid_by_user[ibport] = false;
158 				rc = 0;
159 			}
160 		}
161 	}
162 	mutex_unlock(&smc_ib_devices.mutex);
163 	/* remove smcd devices */
164 	mutex_lock(&smcd_dev_list.mutex);
165 	list_for_each_entry(smcd, &smcd_dev_list.list, list) {
166 		if (smcd->pnetid_by_user &&
167 		    (!pnet_name ||
168 		     smc_pnet_match(pnet_name, smcd->pnetid))) {
169 			pr_warn_ratelimited("smc: smcd device %s "
170 					    "erased user defined pnetid "
171 					    "%.16s\n",
172 					    dev_name(smcd->ops->get_dev(smcd)),
173 					    smcd->pnetid);
174 			memset(smcd->pnetid, 0, SMC_MAX_PNETID_LEN);
175 			smcd->pnetid_by_user = false;
176 			rc = 0;
177 		}
178 	}
179 	mutex_unlock(&smcd_dev_list.mutex);
180 	return rc;
181 }
182 
183 /* Add the reference to a given network device to the pnet table.
184  */
185 static int smc_pnet_add_by_ndev(struct net_device *ndev)
186 {
187 	struct smc_pnetentry *pnetelem, *tmp_pe;
188 	struct smc_pnettable *pnettable;
189 	struct net *net = dev_net(ndev);
190 	struct smc_net *sn;
191 	int rc = -ENOENT;
192 
193 	/* get pnettable for namespace */
194 	sn = net_generic(net, smc_net_id);
195 	pnettable = &sn->pnettable;
196 
197 	mutex_lock(&pnettable->lock);
198 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
199 		if (pnetelem->type == SMC_PNET_ETH && !pnetelem->ndev &&
200 		    !strncmp(pnetelem->eth_name, ndev->name, IFNAMSIZ)) {
201 			netdev_hold(ndev, &pnetelem->dev_tracker, GFP_ATOMIC);
202 			pnetelem->ndev = ndev;
203 			rc = 0;
204 			pr_warn_ratelimited("smc: adding net device %s with "
205 					    "user defined pnetid %.16s\n",
206 					    pnetelem->eth_name,
207 					    pnetelem->pnet_name);
208 			break;
209 		}
210 	}
211 	mutex_unlock(&pnettable->lock);
212 	return rc;
213 }
214 
215 /* Remove the reference to a given network device from the pnet table.
216  */
217 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
218 {
219 	struct smc_pnetentry *pnetelem, *tmp_pe;
220 	struct smc_pnettable *pnettable;
221 	struct net *net = dev_net(ndev);
222 	struct smc_net *sn;
223 	int rc = -ENOENT;
224 
225 	/* get pnettable for namespace */
226 	sn = net_generic(net, smc_net_id);
227 	pnettable = &sn->pnettable;
228 
229 	mutex_lock(&pnettable->lock);
230 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
231 		if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev == ndev) {
232 			netdev_put(pnetelem->ndev, &pnetelem->dev_tracker);
233 			pnetelem->ndev = NULL;
234 			rc = 0;
235 			pr_warn_ratelimited("smc: removing net device %s with "
236 					    "user defined pnetid %.16s\n",
237 					    pnetelem->eth_name,
238 					    pnetelem->pnet_name);
239 			break;
240 		}
241 	}
242 	mutex_unlock(&pnettable->lock);
243 	return rc;
244 }
245 
246 /* Apply pnetid to ib device when no pnetid is set.
247  */
248 static bool smc_pnet_apply_ib(struct smc_ib_device *ib_dev, u8 ib_port,
249 			      char *pnet_name)
250 {
251 	bool applied = false;
252 
253 	mutex_lock(&smc_ib_devices.mutex);
254 	if (!smc_pnet_is_pnetid_set(ib_dev->pnetid[ib_port - 1])) {
255 		memcpy(ib_dev->pnetid[ib_port - 1], pnet_name,
256 		       SMC_MAX_PNETID_LEN);
257 		ib_dev->pnetid_by_user[ib_port - 1] = true;
258 		applied = true;
259 	}
260 	mutex_unlock(&smc_ib_devices.mutex);
261 	return applied;
262 }
263 
264 /* Apply pnetid to smcd device when no pnetid is set.
265  */
266 static bool smc_pnet_apply_smcd(struct smcd_dev *smcd_dev, char *pnet_name)
267 {
268 	bool applied = false;
269 
270 	mutex_lock(&smcd_dev_list.mutex);
271 	if (!smc_pnet_is_pnetid_set(smcd_dev->pnetid)) {
272 		memcpy(smcd_dev->pnetid, pnet_name, SMC_MAX_PNETID_LEN);
273 		smcd_dev->pnetid_by_user = true;
274 		applied = true;
275 	}
276 	mutex_unlock(&smcd_dev_list.mutex);
277 	return applied;
278 }
279 
280 /* The limit for pnetid is 16 characters.
281  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
282  * Lower case letters are converted to upper case.
283  * Interior blanks should not be used.
284  */
285 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
286 {
287 	char *bf = skip_spaces(pnet_name);
288 	size_t len = strlen(bf);
289 	char *end = bf + len;
290 
291 	if (!len)
292 		return false;
293 	while (--end >= bf && isspace(*end))
294 		;
295 	if (end - bf >= SMC_MAX_PNETID_LEN)
296 		return false;
297 	while (bf <= end) {
298 		if (!isalnum(*bf))
299 			return false;
300 		*pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
301 		bf++;
302 	}
303 	*pnetid = '\0';
304 	return true;
305 }
306 
307 /* Find an infiniband device by a given name. The device might not exist. */
308 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
309 {
310 	struct smc_ib_device *ibdev;
311 
312 	mutex_lock(&smc_ib_devices.mutex);
313 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
314 		if (!strncmp(ibdev->ibdev->name, ib_name,
315 			     sizeof(ibdev->ibdev->name)) ||
316 		    (ibdev->ibdev->dev.parent &&
317 		     !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name,
318 			     IB_DEVICE_NAME_MAX - 1))) {
319 			goto out;
320 		}
321 	}
322 	ibdev = NULL;
323 out:
324 	mutex_unlock(&smc_ib_devices.mutex);
325 	return ibdev;
326 }
327 
328 /* Find an smcd device by a given name. The device might not exist. */
329 static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
330 {
331 	struct smcd_dev *smcd_dev;
332 
333 	mutex_lock(&smcd_dev_list.mutex);
334 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
335 		if (!strncmp(dev_name(smcd_dev->ops->get_dev(smcd_dev)),
336 			     smcd_name, IB_DEVICE_NAME_MAX - 1))
337 			goto out;
338 	}
339 	smcd_dev = NULL;
340 out:
341 	mutex_unlock(&smcd_dev_list.mutex);
342 	return smcd_dev;
343 }
344 
345 static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
346 			    char *eth_name, char *pnet_name)
347 {
348 	struct smc_pnetentry *tmp_pe, *new_pe;
349 	struct net_device *ndev, *base_ndev;
350 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
351 	bool new_netdev;
352 	int rc;
353 
354 	/* check if (base) netdev already has a pnetid. If there is one, we do
355 	 * not want to add a pnet table entry
356 	 */
357 	rc = -EEXIST;
358 	ndev = dev_get_by_name(net, eth_name);	/* dev_hold() */
359 	if (ndev) {
360 		base_ndev = pnet_find_base_ndev(ndev);
361 		if (!smc_pnetid_by_dev_port(base_ndev->dev.parent,
362 					    base_ndev->dev_port, ndev_pnetid))
363 			goto out_put;
364 	}
365 
366 	/* add a new netdev entry to the pnet table if there isn't one */
367 	rc = -ENOMEM;
368 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
369 	if (!new_pe)
370 		goto out_put;
371 	new_pe->type = SMC_PNET_ETH;
372 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
373 	strncpy(new_pe->eth_name, eth_name, IFNAMSIZ);
374 	rc = -EEXIST;
375 	new_netdev = true;
376 	mutex_lock(&pnettable->lock);
377 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
378 		if (tmp_pe->type == SMC_PNET_ETH &&
379 		    !strncmp(tmp_pe->eth_name, eth_name, IFNAMSIZ)) {
380 			new_netdev = false;
381 			break;
382 		}
383 	}
384 	if (new_netdev) {
385 		if (ndev) {
386 			new_pe->ndev = ndev;
387 			netdev_tracker_alloc(ndev, &new_pe->dev_tracker,
388 					     GFP_ATOMIC);
389 		}
390 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
391 		mutex_unlock(&pnettable->lock);
392 	} else {
393 		mutex_unlock(&pnettable->lock);
394 		kfree(new_pe);
395 		goto out_put;
396 	}
397 	if (ndev)
398 		pr_warn_ratelimited("smc: net device %s "
399 				    "applied user defined pnetid %.16s\n",
400 				    new_pe->eth_name, new_pe->pnet_name);
401 	return 0;
402 
403 out_put:
404 	dev_put(ndev);
405 	return rc;
406 }
407 
408 static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
409 			   u8 ib_port, char *pnet_name)
410 {
411 	struct smc_pnetentry *tmp_pe, *new_pe;
412 	struct smc_ib_device *ib_dev;
413 	bool smcddev_applied = true;
414 	bool ibdev_applied = true;
415 	struct smcd_dev *smcd;
416 	struct device *dev;
417 	bool new_ibdev;
418 
419 	/* try to apply the pnetid to active devices */
420 	ib_dev = smc_pnet_find_ib(ib_name);
421 	if (ib_dev) {
422 		ibdev_applied = smc_pnet_apply_ib(ib_dev, ib_port, pnet_name);
423 		if (ibdev_applied)
424 			pr_warn_ratelimited("smc: ib device %s ibport %d "
425 					    "applied user defined pnetid "
426 					    "%.16s\n", ib_dev->ibdev->name,
427 					    ib_port,
428 					    ib_dev->pnetid[ib_port - 1]);
429 	}
430 	smcd = smc_pnet_find_smcd(ib_name);
431 	if (smcd) {
432 		smcddev_applied = smc_pnet_apply_smcd(smcd, pnet_name);
433 		if (smcddev_applied) {
434 			dev = smcd->ops->get_dev(smcd);
435 			pr_warn_ratelimited("smc: smcd device %s "
436 					    "applied user defined pnetid "
437 					    "%.16s\n", dev_name(dev),
438 					    smcd->pnetid);
439 		}
440 	}
441 	/* Apply fails when a device has a hardware-defined pnetid set, do not
442 	 * add a pnet table entry in that case.
443 	 */
444 	if (!ibdev_applied || !smcddev_applied)
445 		return -EEXIST;
446 
447 	/* add a new ib entry to the pnet table if there isn't one */
448 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
449 	if (!new_pe)
450 		return -ENOMEM;
451 	new_pe->type = SMC_PNET_IB;
452 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
453 	strncpy(new_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX);
454 	new_pe->ib_port = ib_port;
455 
456 	new_ibdev = true;
457 	mutex_lock(&pnettable->lock);
458 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
459 		if (tmp_pe->type == SMC_PNET_IB &&
460 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
461 			new_ibdev = false;
462 			break;
463 		}
464 	}
465 	if (new_ibdev) {
466 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
467 		mutex_unlock(&pnettable->lock);
468 	} else {
469 		mutex_unlock(&pnettable->lock);
470 		kfree(new_pe);
471 	}
472 	return (new_ibdev) ? 0 : -EEXIST;
473 }
474 
475 /* Append a pnetid to the end of the pnet table if not already on this list.
476  */
477 static int smc_pnet_enter(struct net *net, struct nlattr *tb[])
478 {
479 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
480 	struct smc_pnettable *pnettable;
481 	bool new_netdev = false;
482 	bool new_ibdev = false;
483 	struct smc_net *sn;
484 	u8 ibport = 1;
485 	char *string;
486 	int rc;
487 
488 	/* get pnettable for namespace */
489 	sn = net_generic(net, smc_net_id);
490 	pnettable = &sn->pnettable;
491 
492 	rc = -EINVAL;
493 	if (!tb[SMC_PNETID_NAME])
494 		goto error;
495 	string = (char *)nla_data(tb[SMC_PNETID_NAME]);
496 	if (!smc_pnetid_valid(string, pnet_name))
497 		goto error;
498 
499 	if (tb[SMC_PNETID_ETHNAME]) {
500 		string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
501 		rc = smc_pnet_add_eth(pnettable, net, string, pnet_name);
502 		if (!rc)
503 			new_netdev = true;
504 		else if (rc != -EEXIST)
505 			goto error;
506 	}
507 
508 	/* if this is not the initial namespace, stop here */
509 	if (net != &init_net)
510 		return new_netdev ? 0 : -EEXIST;
511 
512 	rc = -EINVAL;
513 	if (tb[SMC_PNETID_IBNAME]) {
514 		string = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
515 		string = strim(string);
516 		if (tb[SMC_PNETID_IBPORT]) {
517 			ibport = nla_get_u8(tb[SMC_PNETID_IBPORT]);
518 			if (ibport < 1 || ibport > SMC_MAX_PORTS)
519 				goto error;
520 		}
521 		rc = smc_pnet_add_ib(pnettable, string, ibport, pnet_name);
522 		if (!rc)
523 			new_ibdev = true;
524 		else if (rc != -EEXIST)
525 			goto error;
526 	}
527 	return (new_netdev || new_ibdev) ? 0 : -EEXIST;
528 
529 error:
530 	return rc;
531 }
532 
533 /* Convert an smc_pnetentry to a netlink attribute sequence */
534 static int smc_pnet_set_nla(struct sk_buff *msg,
535 			    struct smc_pnetentry *pnetelem)
536 {
537 	if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name))
538 		return -1;
539 	if (pnetelem->type == SMC_PNET_ETH) {
540 		if (nla_put_string(msg, SMC_PNETID_ETHNAME,
541 				   pnetelem->eth_name))
542 			return -1;
543 	} else {
544 		if (nla_put_string(msg, SMC_PNETID_ETHNAME, "n/a"))
545 			return -1;
546 	}
547 	if (pnetelem->type == SMC_PNET_IB) {
548 		if (nla_put_string(msg, SMC_PNETID_IBNAME, pnetelem->ib_name) ||
549 		    nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
550 			return -1;
551 	} else {
552 		if (nla_put_string(msg, SMC_PNETID_IBNAME, "n/a") ||
553 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 0xff))
554 			return -1;
555 	}
556 
557 	return 0;
558 }
559 
560 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
561 {
562 	struct net *net = genl_info_net(info);
563 
564 	return smc_pnet_enter(net, info->attrs);
565 }
566 
567 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
568 {
569 	struct net *net = genl_info_net(info);
570 
571 	if (!info->attrs[SMC_PNETID_NAME])
572 		return -EINVAL;
573 	return smc_pnet_remove_by_pnetid(net,
574 				(char *)nla_data(info->attrs[SMC_PNETID_NAME]));
575 }
576 
577 static int smc_pnet_dump_start(struct netlink_callback *cb)
578 {
579 	cb->args[0] = 0;
580 	return 0;
581 }
582 
583 static int smc_pnet_dumpinfo(struct sk_buff *skb,
584 			     u32 portid, u32 seq, u32 flags,
585 			     struct smc_pnetentry *pnetelem)
586 {
587 	void *hdr;
588 
589 	hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
590 			  flags, SMC_PNETID_GET);
591 	if (!hdr)
592 		return -ENOMEM;
593 	if (smc_pnet_set_nla(skb, pnetelem) < 0) {
594 		genlmsg_cancel(skb, hdr);
595 		return -EMSGSIZE;
596 	}
597 	genlmsg_end(skb, hdr);
598 	return 0;
599 }
600 
601 static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
602 			  u32 seq, u8 *pnetid, int start_idx)
603 {
604 	struct smc_pnettable *pnettable;
605 	struct smc_pnetentry *pnetelem;
606 	struct smc_net *sn;
607 	int idx = 0;
608 
609 	/* get pnettable for namespace */
610 	sn = net_generic(net, smc_net_id);
611 	pnettable = &sn->pnettable;
612 
613 	/* dump pnettable entries */
614 	mutex_lock(&pnettable->lock);
615 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
616 		if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
617 			continue;
618 		if (idx++ < start_idx)
619 			continue;
620 		/* if this is not the initial namespace, dump only netdev */
621 		if (net != &init_net && pnetelem->type != SMC_PNET_ETH)
622 			continue;
623 		if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
624 				      pnetelem)) {
625 			--idx;
626 			break;
627 		}
628 	}
629 	mutex_unlock(&pnettable->lock);
630 	return idx;
631 }
632 
633 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
634 {
635 	struct net *net = sock_net(skb->sk);
636 	int idx;
637 
638 	idx = _smc_pnet_dump(net, skb, NETLINK_CB(cb->skb).portid,
639 			     cb->nlh->nlmsg_seq, NULL, cb->args[0]);
640 
641 	cb->args[0] = idx;
642 	return skb->len;
643 }
644 
645 /* Retrieve one PNETID entry */
646 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
647 {
648 	struct net *net = genl_info_net(info);
649 	struct sk_buff *msg;
650 	void *hdr;
651 
652 	if (!info->attrs[SMC_PNETID_NAME])
653 		return -EINVAL;
654 
655 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
656 	if (!msg)
657 		return -ENOMEM;
658 
659 	_smc_pnet_dump(net, msg, info->snd_portid, info->snd_seq,
660 		       nla_data(info->attrs[SMC_PNETID_NAME]), 0);
661 
662 	/* finish multi part message and send it */
663 	hdr = nlmsg_put(msg, info->snd_portid, info->snd_seq, NLMSG_DONE, 0,
664 			NLM_F_MULTI);
665 	if (!hdr) {
666 		nlmsg_free(msg);
667 		return -EMSGSIZE;
668 	}
669 	return genlmsg_reply(msg, info);
670 }
671 
672 /* Remove and delete all pnetids from pnet table.
673  */
674 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
675 {
676 	struct net *net = genl_info_net(info);
677 
678 	smc_pnet_remove_by_pnetid(net, NULL);
679 	return 0;
680 }
681 
682 /* SMC_PNETID generic netlink operation definition */
683 static const struct genl_ops smc_pnet_ops[] = {
684 	{
685 		.cmd = SMC_PNETID_GET,
686 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
687 		/* can be retrieved by unprivileged users */
688 		.doit = smc_pnet_get,
689 		.dumpit = smc_pnet_dump,
690 		.start = smc_pnet_dump_start
691 	},
692 	{
693 		.cmd = SMC_PNETID_ADD,
694 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
695 		.flags = GENL_ADMIN_PERM,
696 		.doit = smc_pnet_add
697 	},
698 	{
699 		.cmd = SMC_PNETID_DEL,
700 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
701 		.flags = GENL_ADMIN_PERM,
702 		.doit = smc_pnet_del
703 	},
704 	{
705 		.cmd = SMC_PNETID_FLUSH,
706 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
707 		.flags = GENL_ADMIN_PERM,
708 		.doit = smc_pnet_flush
709 	}
710 };
711 
712 /* SMC_PNETID family definition */
713 static struct genl_family smc_pnet_nl_family __ro_after_init = {
714 	.hdrsize = 0,
715 	.name = SMCR_GENL_FAMILY_NAME,
716 	.version = SMCR_GENL_FAMILY_VERSION,
717 	.maxattr = SMC_PNETID_MAX,
718 	.policy = smc_pnet_policy,
719 	.netnsok = true,
720 	.module = THIS_MODULE,
721 	.ops = smc_pnet_ops,
722 	.n_ops =  ARRAY_SIZE(smc_pnet_ops),
723 	.resv_start_op = SMC_PNETID_FLUSH + 1,
724 };
725 
726 bool smc_pnet_is_ndev_pnetid(struct net *net, u8 *pnetid)
727 {
728 	struct smc_net *sn = net_generic(net, smc_net_id);
729 	struct smc_pnetids_ndev_entry *pe;
730 	bool rc = false;
731 
732 	read_lock(&sn->pnetids_ndev.lock);
733 	list_for_each_entry(pe, &sn->pnetids_ndev.list, list) {
734 		if (smc_pnet_match(pnetid, pe->pnetid)) {
735 			rc = true;
736 			goto unlock;
737 		}
738 	}
739 
740 unlock:
741 	read_unlock(&sn->pnetids_ndev.lock);
742 	return rc;
743 }
744 
745 static int smc_pnet_add_pnetid(struct net *net, u8 *pnetid)
746 {
747 	struct smc_net *sn = net_generic(net, smc_net_id);
748 	struct smc_pnetids_ndev_entry *pe, *pi;
749 
750 	pe = kzalloc(sizeof(*pe), GFP_KERNEL);
751 	if (!pe)
752 		return -ENOMEM;
753 
754 	write_lock(&sn->pnetids_ndev.lock);
755 	list_for_each_entry(pi, &sn->pnetids_ndev.list, list) {
756 		if (smc_pnet_match(pnetid, pe->pnetid)) {
757 			refcount_inc(&pi->refcnt);
758 			kfree(pe);
759 			goto unlock;
760 		}
761 	}
762 	refcount_set(&pe->refcnt, 1);
763 	memcpy(pe->pnetid, pnetid, SMC_MAX_PNETID_LEN);
764 	list_add_tail(&pe->list, &sn->pnetids_ndev.list);
765 
766 unlock:
767 	write_unlock(&sn->pnetids_ndev.lock);
768 	return 0;
769 }
770 
771 static void smc_pnet_remove_pnetid(struct net *net, u8 *pnetid)
772 {
773 	struct smc_net *sn = net_generic(net, smc_net_id);
774 	struct smc_pnetids_ndev_entry *pe, *pe2;
775 
776 	write_lock(&sn->pnetids_ndev.lock);
777 	list_for_each_entry_safe(pe, pe2, &sn->pnetids_ndev.list, list) {
778 		if (smc_pnet_match(pnetid, pe->pnetid)) {
779 			if (refcount_dec_and_test(&pe->refcnt)) {
780 				list_del(&pe->list);
781 				kfree(pe);
782 			}
783 			break;
784 		}
785 	}
786 	write_unlock(&sn->pnetids_ndev.lock);
787 }
788 
789 static void smc_pnet_add_base_pnetid(struct net *net, struct net_device *dev,
790 				     u8 *ndev_pnetid)
791 {
792 	struct net_device *base_dev;
793 
794 	base_dev = __pnet_find_base_ndev(dev);
795 	if (base_dev->flags & IFF_UP &&
796 	    !smc_pnetid_by_dev_port(base_dev->dev.parent, base_dev->dev_port,
797 				    ndev_pnetid)) {
798 		/* add to PNETIDs list */
799 		smc_pnet_add_pnetid(net, ndev_pnetid);
800 	}
801 }
802 
803 /* create initial list of netdevice pnetids */
804 static void smc_pnet_create_pnetids_list(struct net *net)
805 {
806 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
807 	struct net_device *dev;
808 
809 	/* Newly created netns do not have devices.
810 	 * Do not even acquire rtnl.
811 	 */
812 	if (list_empty(&net->dev_base_head))
813 		return;
814 
815 	/* Note: This might not be needed, because smc_pnet_netdev_event()
816 	 * is also calling smc_pnet_add_base_pnetid() when handling
817 	 * NETDEV_UP event.
818 	 */
819 	rtnl_lock();
820 	for_each_netdev(net, dev)
821 		smc_pnet_add_base_pnetid(net, dev, ndev_pnetid);
822 	rtnl_unlock();
823 }
824 
825 /* clean up list of netdevice pnetids */
826 static void smc_pnet_destroy_pnetids_list(struct net *net)
827 {
828 	struct smc_net *sn = net_generic(net, smc_net_id);
829 	struct smc_pnetids_ndev_entry *pe, *temp_pe;
830 
831 	write_lock(&sn->pnetids_ndev.lock);
832 	list_for_each_entry_safe(pe, temp_pe, &sn->pnetids_ndev.list, list) {
833 		list_del(&pe->list);
834 		kfree(pe);
835 	}
836 	write_unlock(&sn->pnetids_ndev.lock);
837 }
838 
839 static int smc_pnet_netdev_event(struct notifier_block *this,
840 				 unsigned long event, void *ptr)
841 {
842 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
843 	struct net *net = dev_net(event_dev);
844 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
845 
846 	switch (event) {
847 	case NETDEV_REBOOT:
848 	case NETDEV_UNREGISTER:
849 		smc_pnet_remove_by_ndev(event_dev);
850 		smc_ib_ndev_change(event_dev, event);
851 		return NOTIFY_OK;
852 	case NETDEV_REGISTER:
853 		smc_pnet_add_by_ndev(event_dev);
854 		smc_ib_ndev_change(event_dev, event);
855 		return NOTIFY_OK;
856 	case NETDEV_UP:
857 		smc_pnet_add_base_pnetid(net, event_dev, ndev_pnetid);
858 		return NOTIFY_OK;
859 	case NETDEV_DOWN:
860 		event_dev = __pnet_find_base_ndev(event_dev);
861 		if (!smc_pnetid_by_dev_port(event_dev->dev.parent,
862 					    event_dev->dev_port, ndev_pnetid)) {
863 			/* remove from PNETIDs list */
864 			smc_pnet_remove_pnetid(net, ndev_pnetid);
865 		}
866 		return NOTIFY_OK;
867 	default:
868 		return NOTIFY_DONE;
869 	}
870 }
871 
872 static struct notifier_block smc_netdev_notifier = {
873 	.notifier_call = smc_pnet_netdev_event
874 };
875 
876 /* init network namespace */
877 int smc_pnet_net_init(struct net *net)
878 {
879 	struct smc_net *sn = net_generic(net, smc_net_id);
880 	struct smc_pnettable *pnettable = &sn->pnettable;
881 	struct smc_pnetids_ndev *pnetids_ndev = &sn->pnetids_ndev;
882 
883 	INIT_LIST_HEAD(&pnettable->pnetlist);
884 	mutex_init(&pnettable->lock);
885 	INIT_LIST_HEAD(&pnetids_ndev->list);
886 	rwlock_init(&pnetids_ndev->lock);
887 
888 	smc_pnet_create_pnetids_list(net);
889 
890 	return 0;
891 }
892 
893 int __init smc_pnet_init(void)
894 {
895 	int rc;
896 
897 	rc = genl_register_family(&smc_pnet_nl_family);
898 	if (rc)
899 		return rc;
900 	rc = register_netdevice_notifier(&smc_netdev_notifier);
901 	if (rc)
902 		genl_unregister_family(&smc_pnet_nl_family);
903 
904 	return rc;
905 }
906 
907 /* exit network namespace */
908 void smc_pnet_net_exit(struct net *net)
909 {
910 	/* flush pnet table */
911 	smc_pnet_remove_by_pnetid(net, NULL);
912 	smc_pnet_destroy_pnetids_list(net);
913 }
914 
915 void smc_pnet_exit(void)
916 {
917 	unregister_netdevice_notifier(&smc_netdev_notifier);
918 	genl_unregister_family(&smc_pnet_nl_family);
919 }
920 
921 static struct net_device *__pnet_find_base_ndev(struct net_device *ndev)
922 {
923 	int i, nest_lvl;
924 
925 	ASSERT_RTNL();
926 	nest_lvl = ndev->lower_level;
927 	for (i = 0; i < nest_lvl; i++) {
928 		struct list_head *lower = &ndev->adj_list.lower;
929 
930 		if (list_empty(lower))
931 			break;
932 		lower = lower->next;
933 		ndev = netdev_lower_get_next(ndev, &lower);
934 	}
935 	return ndev;
936 }
937 
938 /* Determine one base device for stacked net devices.
939  * If the lower device level contains more than one devices
940  * (for instance with bonding slaves), just the first device
941  * is used to reach a base device.
942  */
943 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
944 {
945 	rtnl_lock();
946 	ndev = __pnet_find_base_ndev(ndev);
947 	rtnl_unlock();
948 	return ndev;
949 }
950 
951 static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
952 					      u8 *pnetid)
953 {
954 	struct smc_pnettable *pnettable;
955 	struct net *net = dev_net(ndev);
956 	struct smc_pnetentry *pnetelem;
957 	struct smc_net *sn;
958 	int rc = -ENOENT;
959 
960 	/* get pnettable for namespace */
961 	sn = net_generic(net, smc_net_id);
962 	pnettable = &sn->pnettable;
963 
964 	mutex_lock(&pnettable->lock);
965 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
966 		if (pnetelem->type == SMC_PNET_ETH && ndev == pnetelem->ndev) {
967 			/* get pnetid of netdev device */
968 			memcpy(pnetid, pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
969 			rc = 0;
970 			break;
971 		}
972 	}
973 	mutex_unlock(&pnettable->lock);
974 	return rc;
975 }
976 
977 static int smc_pnet_determine_gid(struct smc_ib_device *ibdev, int i,
978 				  struct smc_init_info *ini)
979 {
980 	if (!ini->check_smcrv2 &&
981 	    !smc_ib_determine_gid(ibdev, i, ini->vlan_id, ini->ib_gid, NULL,
982 				  NULL)) {
983 		ini->ib_dev = ibdev;
984 		ini->ib_port = i;
985 		return 0;
986 	}
987 	if (ini->check_smcrv2 &&
988 	    !smc_ib_determine_gid(ibdev, i, ini->vlan_id, ini->smcrv2.ib_gid_v2,
989 				  NULL, &ini->smcrv2)) {
990 		ini->smcrv2.ib_dev_v2 = ibdev;
991 		ini->smcrv2.ib_port_v2 = i;
992 		return 0;
993 	}
994 	return -ENODEV;
995 }
996 
997 /* find a roce device for the given pnetid */
998 static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
999 					  struct smc_init_info *ini,
1000 					  struct smc_ib_device *known_dev,
1001 					  struct net *net)
1002 {
1003 	struct smc_ib_device *ibdev;
1004 	int i;
1005 
1006 	mutex_lock(&smc_ib_devices.mutex);
1007 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
1008 		if (ibdev == known_dev ||
1009 		    !rdma_dev_access_netns(ibdev->ibdev, net))
1010 			continue;
1011 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
1012 			if (!rdma_is_port_valid(ibdev->ibdev, i))
1013 				continue;
1014 			if (smc_pnet_match(ibdev->pnetid[i - 1], pnet_id) &&
1015 			    smc_ib_port_active(ibdev, i) &&
1016 			    !test_bit(i - 1, ibdev->ports_going_away)) {
1017 				if (!smc_pnet_determine_gid(ibdev, i, ini))
1018 					goto out;
1019 			}
1020 		}
1021 	}
1022 out:
1023 	mutex_unlock(&smc_ib_devices.mutex);
1024 }
1025 
1026 /* find alternate roce device with same pnet_id, vlan_id and net namespace */
1027 void smc_pnet_find_alt_roce(struct smc_link_group *lgr,
1028 			    struct smc_init_info *ini,
1029 			    struct smc_ib_device *known_dev)
1030 {
1031 	struct net *net = lgr->net;
1032 
1033 	_smc_pnet_find_roce_by_pnetid(lgr->pnet_id, ini, known_dev, net);
1034 }
1035 
1036 /* if handshake network device belongs to a roce device, return its
1037  * IB device and port
1038  */
1039 static void smc_pnet_find_rdma_dev(struct net_device *netdev,
1040 				   struct smc_init_info *ini)
1041 {
1042 	struct net *net = dev_net(netdev);
1043 	struct smc_ib_device *ibdev;
1044 
1045 	mutex_lock(&smc_ib_devices.mutex);
1046 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
1047 		struct net_device *ndev;
1048 		int i;
1049 
1050 		/* check rdma net namespace */
1051 		if (!rdma_dev_access_netns(ibdev->ibdev, net))
1052 			continue;
1053 
1054 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
1055 			if (!rdma_is_port_valid(ibdev->ibdev, i))
1056 				continue;
1057 			if (!ibdev->ibdev->ops.get_netdev)
1058 				continue;
1059 			ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
1060 			if (!ndev)
1061 				continue;
1062 			dev_put(ndev);
1063 			if (netdev == ndev &&
1064 			    smc_ib_port_active(ibdev, i) &&
1065 			    !test_bit(i - 1, ibdev->ports_going_away)) {
1066 				if (!smc_pnet_determine_gid(ibdev, i, ini))
1067 					break;
1068 			}
1069 		}
1070 	}
1071 	mutex_unlock(&smc_ib_devices.mutex);
1072 }
1073 
1074 /* Determine the corresponding IB device port based on the hardware PNETID.
1075  * Searching stops at the first matching active IB device port with vlan_id
1076  * configured.
1077  * If nothing found, check pnetid table.
1078  * If nothing found, try to use handshake device
1079  */
1080 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
1081 					 struct smc_init_info *ini)
1082 {
1083 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
1084 	struct net *net;
1085 
1086 	ndev = pnet_find_base_ndev(ndev);
1087 	net = dev_net(ndev);
1088 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
1089 				   ndev_pnetid) &&
1090 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
1091 		smc_pnet_find_rdma_dev(ndev, ini);
1092 		return; /* pnetid could not be determined */
1093 	}
1094 	_smc_pnet_find_roce_by_pnetid(ndev_pnetid, ini, NULL, net);
1095 }
1096 
1097 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
1098 					struct smc_init_info *ini)
1099 {
1100 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
1101 	struct smcd_dev *ismdev;
1102 
1103 	ndev = pnet_find_base_ndev(ndev);
1104 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
1105 				   ndev_pnetid) &&
1106 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
1107 		return; /* pnetid could not be determined */
1108 
1109 	mutex_lock(&smcd_dev_list.mutex);
1110 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
1111 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid) &&
1112 		    !ismdev->going_away &&
1113 		    (!ini->ism_peer_gid[0].gid ||
1114 		     !smc_ism_cantalk(&ini->ism_peer_gid[0], ini->vlan_id,
1115 				      ismdev))) {
1116 			ini->ism_dev[0] = ismdev;
1117 			break;
1118 		}
1119 	}
1120 	mutex_unlock(&smcd_dev_list.mutex);
1121 }
1122 
1123 /* PNET table analysis for a given sock:
1124  * determine ib_device and port belonging to used internal TCP socket
1125  * ethernet interface.
1126  */
1127 void smc_pnet_find_roce_resource(struct sock *sk, struct smc_init_info *ini)
1128 {
1129 	struct dst_entry *dst = sk_dst_get(sk);
1130 
1131 	if (!dst)
1132 		goto out;
1133 	if (!dst->dev)
1134 		goto out_rel;
1135 
1136 	smc_pnet_find_roce_by_pnetid(dst->dev, ini);
1137 
1138 out_rel:
1139 	dst_release(dst);
1140 out:
1141 	return;
1142 }
1143 
1144 void smc_pnet_find_ism_resource(struct sock *sk, struct smc_init_info *ini)
1145 {
1146 	struct dst_entry *dst = sk_dst_get(sk);
1147 
1148 	ini->ism_dev[0] = NULL;
1149 	if (!dst)
1150 		goto out;
1151 	if (!dst->dev)
1152 		goto out_rel;
1153 
1154 	smc_pnet_find_ism_by_pnetid(dst->dev, ini);
1155 
1156 out_rel:
1157 	dst_release(dst);
1158 out:
1159 	return;
1160 }
1161 
1162 /* Lookup and apply a pnet table entry to the given ib device.
1163  */
1164 int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
1165 {
1166 	char *ib_name = smcibdev->ibdev->name;
1167 	struct smc_pnettable *pnettable;
1168 	struct smc_pnetentry *tmp_pe;
1169 	struct smc_net *sn;
1170 	int rc = -ENOENT;
1171 
1172 	/* get pnettable for init namespace */
1173 	sn = net_generic(&init_net, smc_net_id);
1174 	pnettable = &sn->pnettable;
1175 
1176 	mutex_lock(&pnettable->lock);
1177 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
1178 		if (tmp_pe->type == SMC_PNET_IB &&
1179 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX) &&
1180 		    tmp_pe->ib_port == ib_port) {
1181 			smc_pnet_apply_ib(smcibdev, ib_port, tmp_pe->pnet_name);
1182 			rc = 0;
1183 			break;
1184 		}
1185 	}
1186 	mutex_unlock(&pnettable->lock);
1187 
1188 	return rc;
1189 }
1190 
1191 /* Lookup and apply a pnet table entry to the given smcd device.
1192  */
1193 int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
1194 {
1195 	const char *ib_name = dev_name(smcddev->ops->get_dev(smcddev));
1196 	struct smc_pnettable *pnettable;
1197 	struct smc_pnetentry *tmp_pe;
1198 	struct smc_net *sn;
1199 	int rc = -ENOENT;
1200 
1201 	/* get pnettable for init namespace */
1202 	sn = net_generic(&init_net, smc_net_id);
1203 	pnettable = &sn->pnettable;
1204 
1205 	mutex_lock(&pnettable->lock);
1206 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
1207 		if (tmp_pe->type == SMC_PNET_IB &&
1208 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
1209 			smc_pnet_apply_smcd(smcddev, tmp_pe->pnet_name);
1210 			rc = 0;
1211 			break;
1212 		}
1213 	}
1214 	mutex_unlock(&pnettable->lock);
1215 
1216 	return rc;
1217 }
1218