xref: /openbmc/linux/net/smc/smc_pnet.c (revision 11788d9b)
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 #define SMC_ASCII_BLANK 32
33 
34 static struct net_device *pnet_find_base_ndev(struct net_device *ndev);
35 
36 static const struct nla_policy smc_pnet_policy[SMC_PNETID_MAX + 1] = {
37 	[SMC_PNETID_NAME] = {
38 		.type = NLA_NUL_STRING,
39 		.len = SMC_MAX_PNETID_LEN
40 	},
41 	[SMC_PNETID_ETHNAME] = {
42 		.type = NLA_NUL_STRING,
43 		.len = IFNAMSIZ - 1
44 	},
45 	[SMC_PNETID_IBNAME] = {
46 		.type = NLA_NUL_STRING,
47 		.len = IB_DEVICE_NAME_MAX - 1
48 	},
49 	[SMC_PNETID_IBPORT] = { .type = NLA_U8 }
50 };
51 
52 static struct genl_family smc_pnet_nl_family;
53 
54 enum smc_pnet_nametype {
55 	SMC_PNET_ETH	= 1,
56 	SMC_PNET_IB	= 2,
57 };
58 
59 /* pnet entry stored in pnet table */
60 struct smc_pnetentry {
61 	struct list_head list;
62 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
63 	enum smc_pnet_nametype type;
64 	union {
65 		struct {
66 			char eth_name[IFNAMSIZ + 1];
67 			struct net_device *ndev;
68 		};
69 		struct {
70 			char ib_name[IB_DEVICE_NAME_MAX + 1];
71 			u8 ib_port;
72 		};
73 	};
74 };
75 
76 /* Check if two given pnetids match */
77 static bool smc_pnet_match(u8 *pnetid1, u8 *pnetid2)
78 {
79 	int i;
80 
81 	for (i = 0; i < SMC_MAX_PNETID_LEN; i++) {
82 		if ((pnetid1[i] == 0 || pnetid1[i] == SMC_ASCII_BLANK) &&
83 		    (pnetid2[i] == 0 || pnetid2[i] == SMC_ASCII_BLANK))
84 			break;
85 		if (pnetid1[i] != pnetid2[i])
86 			return false;
87 	}
88 	return true;
89 }
90 
91 /* Remove a pnetid from the pnet table.
92  */
93 static int smc_pnet_remove_by_pnetid(struct net *net, char *pnet_name)
94 {
95 	struct smc_pnetentry *pnetelem, *tmp_pe;
96 	struct smc_pnettable *pnettable;
97 	struct smc_ib_device *ibdev;
98 	struct smcd_dev *smcd_dev;
99 	struct smc_net *sn;
100 	int rc = -ENOENT;
101 	int ibport;
102 
103 	/* get pnettable for namespace */
104 	sn = net_generic(net, smc_net_id);
105 	pnettable = &sn->pnettable;
106 
107 	/* remove table entry */
108 	write_lock(&pnettable->lock);
109 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist,
110 				 list) {
111 		if (!pnet_name ||
112 		    smc_pnet_match(pnetelem->pnet_name, pnet_name)) {
113 			list_del(&pnetelem->list);
114 			if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev) {
115 				dev_put(pnetelem->ndev);
116 				pr_warn_ratelimited("smc: net device %s "
117 						    "erased user defined "
118 						    "pnetid %.16s\n",
119 						    pnetelem->eth_name,
120 						    pnetelem->pnet_name);
121 			}
122 			kfree(pnetelem);
123 			rc = 0;
124 		}
125 	}
126 	write_unlock(&pnettable->lock);
127 
128 	/* if this is not the initial namespace, stop here */
129 	if (net != &init_net)
130 		return rc;
131 
132 	/* remove ib devices */
133 	mutex_lock(&smc_ib_devices.mutex);
134 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
135 		for (ibport = 0; ibport < SMC_MAX_PORTS; ibport++) {
136 			if (ibdev->pnetid_by_user[ibport] &&
137 			    (!pnet_name ||
138 			     smc_pnet_match(pnet_name,
139 					    ibdev->pnetid[ibport]))) {
140 				pr_warn_ratelimited("smc: ib device %s ibport "
141 						    "%d erased user defined "
142 						    "pnetid %.16s\n",
143 						    ibdev->ibdev->name,
144 						    ibport + 1,
145 						    ibdev->pnetid[ibport]);
146 				memset(ibdev->pnetid[ibport], 0,
147 				       SMC_MAX_PNETID_LEN);
148 				ibdev->pnetid_by_user[ibport] = false;
149 				rc = 0;
150 			}
151 		}
152 	}
153 	mutex_unlock(&smc_ib_devices.mutex);
154 	/* remove smcd devices */
155 	mutex_lock(&smcd_dev_list.mutex);
156 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
157 		if (smcd_dev->pnetid_by_user &&
158 		    (!pnet_name ||
159 		     smc_pnet_match(pnet_name, smcd_dev->pnetid))) {
160 			pr_warn_ratelimited("smc: smcd device %s "
161 					    "erased user defined pnetid "
162 					    "%.16s\n", dev_name(&smcd_dev->dev),
163 					    smcd_dev->pnetid);
164 			memset(smcd_dev->pnetid, 0, SMC_MAX_PNETID_LEN);
165 			smcd_dev->pnetid_by_user = false;
166 			rc = 0;
167 		}
168 	}
169 	mutex_unlock(&smcd_dev_list.mutex);
170 	return rc;
171 }
172 
173 /* Add the reference to a given network device to the pnet table.
174  */
175 static int smc_pnet_add_by_ndev(struct net_device *ndev)
176 {
177 	struct smc_pnetentry *pnetelem, *tmp_pe;
178 	struct smc_pnettable *pnettable;
179 	struct net *net = dev_net(ndev);
180 	struct smc_net *sn;
181 	int rc = -ENOENT;
182 
183 	/* get pnettable for namespace */
184 	sn = net_generic(net, smc_net_id);
185 	pnettable = &sn->pnettable;
186 
187 	write_lock(&pnettable->lock);
188 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
189 		if (pnetelem->type == SMC_PNET_ETH && !pnetelem->ndev &&
190 		    !strncmp(pnetelem->eth_name, ndev->name, IFNAMSIZ)) {
191 			dev_hold(ndev);
192 			pnetelem->ndev = ndev;
193 			rc = 0;
194 			pr_warn_ratelimited("smc: adding net device %s with "
195 					    "user defined pnetid %.16s\n",
196 					    pnetelem->eth_name,
197 					    pnetelem->pnet_name);
198 			break;
199 		}
200 	}
201 	write_unlock(&pnettable->lock);
202 	return rc;
203 }
204 
205 /* Remove the reference to a given network device from the pnet table.
206  */
207 static int smc_pnet_remove_by_ndev(struct net_device *ndev)
208 {
209 	struct smc_pnetentry *pnetelem, *tmp_pe;
210 	struct smc_pnettable *pnettable;
211 	struct net *net = dev_net(ndev);
212 	struct smc_net *sn;
213 	int rc = -ENOENT;
214 
215 	/* get pnettable for namespace */
216 	sn = net_generic(net, smc_net_id);
217 	pnettable = &sn->pnettable;
218 
219 	write_lock(&pnettable->lock);
220 	list_for_each_entry_safe(pnetelem, tmp_pe, &pnettable->pnetlist, list) {
221 		if (pnetelem->type == SMC_PNET_ETH && pnetelem->ndev == ndev) {
222 			dev_put(pnetelem->ndev);
223 			pnetelem->ndev = NULL;
224 			rc = 0;
225 			pr_warn_ratelimited("smc: removing net device %s with "
226 					    "user defined pnetid %.16s\n",
227 					    pnetelem->eth_name,
228 					    pnetelem->pnet_name);
229 			break;
230 		}
231 	}
232 	write_unlock(&pnettable->lock);
233 	return rc;
234 }
235 
236 /* Apply pnetid to ib device when no pnetid is set.
237  */
238 static bool smc_pnet_apply_ib(struct smc_ib_device *ib_dev, u8 ib_port,
239 			      char *pnet_name)
240 {
241 	u8 pnet_null[SMC_MAX_PNETID_LEN] = {0};
242 	bool applied = false;
243 
244 	mutex_lock(&smc_ib_devices.mutex);
245 	if (smc_pnet_match(ib_dev->pnetid[ib_port - 1], pnet_null)) {
246 		memcpy(ib_dev->pnetid[ib_port - 1], pnet_name,
247 		       SMC_MAX_PNETID_LEN);
248 		ib_dev->pnetid_by_user[ib_port - 1] = true;
249 		applied = true;
250 	}
251 	mutex_unlock(&smc_ib_devices.mutex);
252 	return applied;
253 }
254 
255 /* Apply pnetid to smcd device when no pnetid is set.
256  */
257 static bool smc_pnet_apply_smcd(struct smcd_dev *smcd_dev, char *pnet_name)
258 {
259 	u8 pnet_null[SMC_MAX_PNETID_LEN] = {0};
260 	bool applied = false;
261 
262 	mutex_lock(&smcd_dev_list.mutex);
263 	if (smc_pnet_match(smcd_dev->pnetid, pnet_null)) {
264 		memcpy(smcd_dev->pnetid, pnet_name, SMC_MAX_PNETID_LEN);
265 		smcd_dev->pnetid_by_user = true;
266 		applied = true;
267 	}
268 	mutex_unlock(&smcd_dev_list.mutex);
269 	return applied;
270 }
271 
272 /* The limit for pnetid is 16 characters.
273  * Valid characters should be (single-byte character set) a-z, A-Z, 0-9.
274  * Lower case letters are converted to upper case.
275  * Interior blanks should not be used.
276  */
277 static bool smc_pnetid_valid(const char *pnet_name, char *pnetid)
278 {
279 	char *bf = skip_spaces(pnet_name);
280 	size_t len = strlen(bf);
281 	char *end = bf + len;
282 
283 	if (!len)
284 		return false;
285 	while (--end >= bf && isspace(*end))
286 		;
287 	if (end - bf >= SMC_MAX_PNETID_LEN)
288 		return false;
289 	while (bf <= end) {
290 		if (!isalnum(*bf))
291 			return false;
292 		*pnetid++ = islower(*bf) ? toupper(*bf) : *bf;
293 		bf++;
294 	}
295 	*pnetid = '\0';
296 	return true;
297 }
298 
299 /* Find an infiniband device by a given name. The device might not exist. */
300 static struct smc_ib_device *smc_pnet_find_ib(char *ib_name)
301 {
302 	struct smc_ib_device *ibdev;
303 
304 	mutex_lock(&smc_ib_devices.mutex);
305 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
306 		if (!strncmp(ibdev->ibdev->name, ib_name,
307 			     sizeof(ibdev->ibdev->name)) ||
308 		    !strncmp(dev_name(ibdev->ibdev->dev.parent), ib_name,
309 			     IB_DEVICE_NAME_MAX - 1)) {
310 			goto out;
311 		}
312 	}
313 	ibdev = NULL;
314 out:
315 	mutex_unlock(&smc_ib_devices.mutex);
316 	return ibdev;
317 }
318 
319 /* Find an smcd device by a given name. The device might not exist. */
320 static struct smcd_dev *smc_pnet_find_smcd(char *smcd_name)
321 {
322 	struct smcd_dev *smcd_dev;
323 
324 	mutex_lock(&smcd_dev_list.mutex);
325 	list_for_each_entry(smcd_dev, &smcd_dev_list.list, list) {
326 		if (!strncmp(dev_name(&smcd_dev->dev), smcd_name,
327 			     IB_DEVICE_NAME_MAX - 1))
328 			goto out;
329 	}
330 	smcd_dev = NULL;
331 out:
332 	mutex_unlock(&smcd_dev_list.mutex);
333 	return smcd_dev;
334 }
335 
336 static int smc_pnet_add_eth(struct smc_pnettable *pnettable, struct net *net,
337 			    char *eth_name, char *pnet_name)
338 {
339 	struct smc_pnetentry *tmp_pe, *new_pe;
340 	struct net_device *ndev, *base_ndev;
341 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
342 	bool new_netdev;
343 	int rc;
344 
345 	/* check if (base) netdev already has a pnetid. If there is one, we do
346 	 * not want to add a pnet table entry
347 	 */
348 	rc = -EEXIST;
349 	ndev = dev_get_by_name(net, eth_name);	/* dev_hold() */
350 	if (ndev) {
351 		base_ndev = pnet_find_base_ndev(ndev);
352 		if (!smc_pnetid_by_dev_port(base_ndev->dev.parent,
353 					    base_ndev->dev_port, ndev_pnetid))
354 			goto out_put;
355 	}
356 
357 	/* add a new netdev entry to the pnet table if there isn't one */
358 	rc = -ENOMEM;
359 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
360 	if (!new_pe)
361 		goto out_put;
362 	new_pe->type = SMC_PNET_ETH;
363 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
364 	strncpy(new_pe->eth_name, eth_name, IFNAMSIZ);
365 	new_pe->ndev = ndev;
366 
367 	rc = -EEXIST;
368 	new_netdev = true;
369 	write_lock(&pnettable->lock);
370 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
371 		if (tmp_pe->type == SMC_PNET_ETH &&
372 		    !strncmp(tmp_pe->eth_name, eth_name, IFNAMSIZ)) {
373 			new_netdev = false;
374 			break;
375 		}
376 	}
377 	if (new_netdev) {
378 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
379 		write_unlock(&pnettable->lock);
380 	} else {
381 		write_unlock(&pnettable->lock);
382 		kfree(new_pe);
383 		goto out_put;
384 	}
385 	if (ndev)
386 		pr_warn_ratelimited("smc: net device %s "
387 				    "applied user defined pnetid %.16s\n",
388 				    new_pe->eth_name, new_pe->pnet_name);
389 	return 0;
390 
391 out_put:
392 	if (ndev)
393 		dev_put(ndev);
394 	return rc;
395 }
396 
397 static int smc_pnet_add_ib(struct smc_pnettable *pnettable, char *ib_name,
398 			   u8 ib_port, char *pnet_name)
399 {
400 	struct smc_pnetentry *tmp_pe, *new_pe;
401 	struct smc_ib_device *ib_dev;
402 	bool smcddev_applied = true;
403 	bool ibdev_applied = true;
404 	struct smcd_dev *smcd_dev;
405 	bool new_ibdev;
406 
407 	/* try to apply the pnetid to active devices */
408 	ib_dev = smc_pnet_find_ib(ib_name);
409 	if (ib_dev) {
410 		ibdev_applied = smc_pnet_apply_ib(ib_dev, ib_port, pnet_name);
411 		if (ibdev_applied)
412 			pr_warn_ratelimited("smc: ib device %s ibport %d "
413 					    "applied user defined pnetid "
414 					    "%.16s\n", ib_dev->ibdev->name,
415 					    ib_port,
416 					    ib_dev->pnetid[ib_port - 1]);
417 	}
418 	smcd_dev = smc_pnet_find_smcd(ib_name);
419 	if (smcd_dev) {
420 		smcddev_applied = smc_pnet_apply_smcd(smcd_dev, pnet_name);
421 		if (smcddev_applied)
422 			pr_warn_ratelimited("smc: smcd device %s "
423 					    "applied user defined pnetid "
424 					    "%.16s\n", dev_name(&smcd_dev->dev),
425 					    smcd_dev->pnetid);
426 	}
427 	/* Apply fails when a device has a hardware-defined pnetid set, do not
428 	 * add a pnet table entry in that case.
429 	 */
430 	if (!ibdev_applied || !smcddev_applied)
431 		return -EEXIST;
432 
433 	/* add a new ib entry to the pnet table if there isn't one */
434 	new_pe = kzalloc(sizeof(*new_pe), GFP_KERNEL);
435 	if (!new_pe)
436 		return -ENOMEM;
437 	new_pe->type = SMC_PNET_IB;
438 	memcpy(new_pe->pnet_name, pnet_name, SMC_MAX_PNETID_LEN);
439 	strncpy(new_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX);
440 	new_pe->ib_port = ib_port;
441 
442 	new_ibdev = true;
443 	write_lock(&pnettable->lock);
444 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
445 		if (tmp_pe->type == SMC_PNET_IB &&
446 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
447 			new_ibdev = false;
448 			break;
449 		}
450 	}
451 	if (new_ibdev) {
452 		list_add_tail(&new_pe->list, &pnettable->pnetlist);
453 		write_unlock(&pnettable->lock);
454 	} else {
455 		write_unlock(&pnettable->lock);
456 		kfree(new_pe);
457 	}
458 	return (new_ibdev) ? 0 : -EEXIST;
459 }
460 
461 /* Append a pnetid to the end of the pnet table if not already on this list.
462  */
463 static int smc_pnet_enter(struct net *net, struct nlattr *tb[])
464 {
465 	char pnet_name[SMC_MAX_PNETID_LEN + 1];
466 	struct smc_pnettable *pnettable;
467 	bool new_netdev = false;
468 	bool new_ibdev = false;
469 	struct smc_net *sn;
470 	u8 ibport = 1;
471 	char *string;
472 	int rc;
473 
474 	/* get pnettable for namespace */
475 	sn = net_generic(net, smc_net_id);
476 	pnettable = &sn->pnettable;
477 
478 	rc = -EINVAL;
479 	if (!tb[SMC_PNETID_NAME])
480 		goto error;
481 	string = (char *)nla_data(tb[SMC_PNETID_NAME]);
482 	if (!smc_pnetid_valid(string, pnet_name))
483 		goto error;
484 
485 	if (tb[SMC_PNETID_ETHNAME]) {
486 		string = (char *)nla_data(tb[SMC_PNETID_ETHNAME]);
487 		rc = smc_pnet_add_eth(pnettable, net, string, pnet_name);
488 		if (!rc)
489 			new_netdev = true;
490 		else if (rc != -EEXIST)
491 			goto error;
492 	}
493 
494 	/* if this is not the initial namespace, stop here */
495 	if (net != &init_net)
496 		return new_netdev ? 0 : -EEXIST;
497 
498 	rc = -EINVAL;
499 	if (tb[SMC_PNETID_IBNAME]) {
500 		string = (char *)nla_data(tb[SMC_PNETID_IBNAME]);
501 		string = strim(string);
502 		if (tb[SMC_PNETID_IBPORT]) {
503 			ibport = nla_get_u8(tb[SMC_PNETID_IBPORT]);
504 			if (ibport < 1 || ibport > SMC_MAX_PORTS)
505 				goto error;
506 		}
507 		rc = smc_pnet_add_ib(pnettable, string, ibport, pnet_name);
508 		if (!rc)
509 			new_ibdev = true;
510 		else if (rc != -EEXIST)
511 			goto error;
512 	}
513 	return (new_netdev || new_ibdev) ? 0 : -EEXIST;
514 
515 error:
516 	return rc;
517 }
518 
519 /* Convert an smc_pnetentry to a netlink attribute sequence */
520 static int smc_pnet_set_nla(struct sk_buff *msg,
521 			    struct smc_pnetentry *pnetelem)
522 {
523 	if (nla_put_string(msg, SMC_PNETID_NAME, pnetelem->pnet_name))
524 		return -1;
525 	if (pnetelem->type == SMC_PNET_ETH) {
526 		if (nla_put_string(msg, SMC_PNETID_ETHNAME,
527 				   pnetelem->eth_name))
528 			return -1;
529 	} else {
530 		if (nla_put_string(msg, SMC_PNETID_ETHNAME, "n/a"))
531 			return -1;
532 	}
533 	if (pnetelem->type == SMC_PNET_IB) {
534 		if (nla_put_string(msg, SMC_PNETID_IBNAME, pnetelem->ib_name) ||
535 		    nla_put_u8(msg, SMC_PNETID_IBPORT, pnetelem->ib_port))
536 			return -1;
537 	} else {
538 		if (nla_put_string(msg, SMC_PNETID_IBNAME, "n/a") ||
539 		    nla_put_u8(msg, SMC_PNETID_IBPORT, 0xff))
540 			return -1;
541 	}
542 
543 	return 0;
544 }
545 
546 static int smc_pnet_add(struct sk_buff *skb, struct genl_info *info)
547 {
548 	struct net *net = genl_info_net(info);
549 
550 	return smc_pnet_enter(net, info->attrs);
551 }
552 
553 static int smc_pnet_del(struct sk_buff *skb, struct genl_info *info)
554 {
555 	struct net *net = genl_info_net(info);
556 
557 	if (!info->attrs[SMC_PNETID_NAME])
558 		return -EINVAL;
559 	return smc_pnet_remove_by_pnetid(net,
560 				(char *)nla_data(info->attrs[SMC_PNETID_NAME]));
561 }
562 
563 static int smc_pnet_dump_start(struct netlink_callback *cb)
564 {
565 	cb->args[0] = 0;
566 	return 0;
567 }
568 
569 static int smc_pnet_dumpinfo(struct sk_buff *skb,
570 			     u32 portid, u32 seq, u32 flags,
571 			     struct smc_pnetentry *pnetelem)
572 {
573 	void *hdr;
574 
575 	hdr = genlmsg_put(skb, portid, seq, &smc_pnet_nl_family,
576 			  flags, SMC_PNETID_GET);
577 	if (!hdr)
578 		return -ENOMEM;
579 	if (smc_pnet_set_nla(skb, pnetelem) < 0) {
580 		genlmsg_cancel(skb, hdr);
581 		return -EMSGSIZE;
582 	}
583 	genlmsg_end(skb, hdr);
584 	return 0;
585 }
586 
587 static int _smc_pnet_dump(struct net *net, struct sk_buff *skb, u32 portid,
588 			  u32 seq, u8 *pnetid, int start_idx)
589 {
590 	struct smc_pnettable *pnettable;
591 	struct smc_pnetentry *pnetelem;
592 	struct smc_net *sn;
593 	int idx = 0;
594 
595 	/* get pnettable for namespace */
596 	sn = net_generic(net, smc_net_id);
597 	pnettable = &sn->pnettable;
598 
599 	/* dump pnettable entries */
600 	read_lock(&pnettable->lock);
601 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
602 		if (pnetid && !smc_pnet_match(pnetelem->pnet_name, pnetid))
603 			continue;
604 		if (idx++ < start_idx)
605 			continue;
606 		/* if this is not the initial namespace, dump only netdev */
607 		if (net != &init_net && pnetelem->type != SMC_PNET_ETH)
608 			continue;
609 		if (smc_pnet_dumpinfo(skb, portid, seq, NLM_F_MULTI,
610 				      pnetelem)) {
611 			--idx;
612 			break;
613 		}
614 	}
615 	read_unlock(&pnettable->lock);
616 	return idx;
617 }
618 
619 static int smc_pnet_dump(struct sk_buff *skb, struct netlink_callback *cb)
620 {
621 	struct net *net = sock_net(skb->sk);
622 	int idx;
623 
624 	idx = _smc_pnet_dump(net, skb, NETLINK_CB(cb->skb).portid,
625 			     cb->nlh->nlmsg_seq, NULL, cb->args[0]);
626 
627 	cb->args[0] = idx;
628 	return skb->len;
629 }
630 
631 /* Retrieve one PNETID entry */
632 static int smc_pnet_get(struct sk_buff *skb, struct genl_info *info)
633 {
634 	struct net *net = genl_info_net(info);
635 	struct sk_buff *msg;
636 	void *hdr;
637 
638 	if (!info->attrs[SMC_PNETID_NAME])
639 		return -EINVAL;
640 
641 	msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
642 	if (!msg)
643 		return -ENOMEM;
644 
645 	_smc_pnet_dump(net, msg, info->snd_portid, info->snd_seq,
646 		       nla_data(info->attrs[SMC_PNETID_NAME]), 0);
647 
648 	/* finish multi part message and send it */
649 	hdr = nlmsg_put(msg, info->snd_portid, info->snd_seq, NLMSG_DONE, 0,
650 			NLM_F_MULTI);
651 	if (!hdr) {
652 		nlmsg_free(msg);
653 		return -EMSGSIZE;
654 	}
655 	return genlmsg_reply(msg, info);
656 }
657 
658 /* Remove and delete all pnetids from pnet table.
659  */
660 static int smc_pnet_flush(struct sk_buff *skb, struct genl_info *info)
661 {
662 	struct net *net = genl_info_net(info);
663 
664 	smc_pnet_remove_by_pnetid(net, NULL);
665 	return 0;
666 }
667 
668 /* SMC_PNETID generic netlink operation definition */
669 static const struct genl_ops smc_pnet_ops[] = {
670 	{
671 		.cmd = SMC_PNETID_GET,
672 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
673 		/* can be retrieved by unprivileged users */
674 		.doit = smc_pnet_get,
675 		.dumpit = smc_pnet_dump,
676 		.start = smc_pnet_dump_start
677 	},
678 	{
679 		.cmd = SMC_PNETID_ADD,
680 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
681 		.flags = GENL_ADMIN_PERM,
682 		.doit = smc_pnet_add
683 	},
684 	{
685 		.cmd = SMC_PNETID_DEL,
686 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
687 		.flags = GENL_ADMIN_PERM,
688 		.doit = smc_pnet_del
689 	},
690 	{
691 		.cmd = SMC_PNETID_FLUSH,
692 		.validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
693 		.flags = GENL_ADMIN_PERM,
694 		.doit = smc_pnet_flush
695 	}
696 };
697 
698 /* SMC_PNETID family definition */
699 static struct genl_family smc_pnet_nl_family __ro_after_init = {
700 	.hdrsize = 0,
701 	.name = SMCR_GENL_FAMILY_NAME,
702 	.version = SMCR_GENL_FAMILY_VERSION,
703 	.maxattr = SMC_PNETID_MAX,
704 	.policy = smc_pnet_policy,
705 	.netnsok = true,
706 	.module = THIS_MODULE,
707 	.ops = smc_pnet_ops,
708 	.n_ops =  ARRAY_SIZE(smc_pnet_ops)
709 };
710 
711 static int smc_pnet_netdev_event(struct notifier_block *this,
712 				 unsigned long event, void *ptr)
713 {
714 	struct net_device *event_dev = netdev_notifier_info_to_dev(ptr);
715 
716 	switch (event) {
717 	case NETDEV_REBOOT:
718 	case NETDEV_UNREGISTER:
719 		smc_pnet_remove_by_ndev(event_dev);
720 		return NOTIFY_OK;
721 	case NETDEV_REGISTER:
722 		smc_pnet_add_by_ndev(event_dev);
723 		return NOTIFY_OK;
724 	default:
725 		return NOTIFY_DONE;
726 	}
727 }
728 
729 static struct notifier_block smc_netdev_notifier = {
730 	.notifier_call = smc_pnet_netdev_event
731 };
732 
733 /* init network namespace */
734 int smc_pnet_net_init(struct net *net)
735 {
736 	struct smc_net *sn = net_generic(net, smc_net_id);
737 	struct smc_pnettable *pnettable = &sn->pnettable;
738 
739 	INIT_LIST_HEAD(&pnettable->pnetlist);
740 	rwlock_init(&pnettable->lock);
741 
742 	return 0;
743 }
744 
745 int __init smc_pnet_init(void)
746 {
747 	int rc;
748 
749 	rc = genl_register_family(&smc_pnet_nl_family);
750 	if (rc)
751 		return rc;
752 	rc = register_netdevice_notifier(&smc_netdev_notifier);
753 	if (rc)
754 		genl_unregister_family(&smc_pnet_nl_family);
755 	return rc;
756 }
757 
758 /* exit network namespace */
759 void smc_pnet_net_exit(struct net *net)
760 {
761 	/* flush pnet table */
762 	smc_pnet_remove_by_pnetid(net, NULL);
763 }
764 
765 void smc_pnet_exit(void)
766 {
767 	unregister_netdevice_notifier(&smc_netdev_notifier);
768 	genl_unregister_family(&smc_pnet_nl_family);
769 }
770 
771 /* Determine one base device for stacked net devices.
772  * If the lower device level contains more than one devices
773  * (for instance with bonding slaves), just the first device
774  * is used to reach a base device.
775  */
776 static struct net_device *pnet_find_base_ndev(struct net_device *ndev)
777 {
778 	int i, nest_lvl;
779 
780 	rtnl_lock();
781 	nest_lvl = ndev->lower_level;
782 	for (i = 0; i < nest_lvl; i++) {
783 		struct list_head *lower = &ndev->adj_list.lower;
784 
785 		if (list_empty(lower))
786 			break;
787 		lower = lower->next;
788 		ndev = netdev_lower_get_next(ndev, &lower);
789 	}
790 	rtnl_unlock();
791 	return ndev;
792 }
793 
794 static int smc_pnet_find_ndev_pnetid_by_table(struct net_device *ndev,
795 					      u8 *pnetid)
796 {
797 	struct smc_pnettable *pnettable;
798 	struct net *net = dev_net(ndev);
799 	struct smc_pnetentry *pnetelem;
800 	struct smc_net *sn;
801 	int rc = -ENOENT;
802 
803 	/* get pnettable for namespace */
804 	sn = net_generic(net, smc_net_id);
805 	pnettable = &sn->pnettable;
806 
807 	read_lock(&pnettable->lock);
808 	list_for_each_entry(pnetelem, &pnettable->pnetlist, list) {
809 		if (pnetelem->type == SMC_PNET_ETH && ndev == pnetelem->ndev) {
810 			/* get pnetid of netdev device */
811 			memcpy(pnetid, pnetelem->pnet_name, SMC_MAX_PNETID_LEN);
812 			rc = 0;
813 			break;
814 		}
815 	}
816 	read_unlock(&pnettable->lock);
817 	return rc;
818 }
819 
820 /* find a roce device for the given pnetid */
821 static void _smc_pnet_find_roce_by_pnetid(u8 *pnet_id,
822 					  struct smc_init_info *ini,
823 					  struct smc_ib_device *known_dev)
824 {
825 	struct smc_ib_device *ibdev;
826 	int i;
827 
828 	ini->ib_dev = NULL;
829 	mutex_lock(&smc_ib_devices.mutex);
830 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
831 		if (ibdev == known_dev)
832 			continue;
833 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
834 			if (!rdma_is_port_valid(ibdev->ibdev, i))
835 				continue;
836 			if (smc_pnet_match(ibdev->pnetid[i - 1], pnet_id) &&
837 			    smc_ib_port_active(ibdev, i) &&
838 			    !test_bit(i - 1, ibdev->ports_going_away) &&
839 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
840 						  ini->ib_gid, NULL)) {
841 				ini->ib_dev = ibdev;
842 				ini->ib_port = i;
843 				goto out;
844 			}
845 		}
846 	}
847 out:
848 	mutex_unlock(&smc_ib_devices.mutex);
849 }
850 
851 /* find alternate roce device with same pnet_id and vlan_id */
852 void smc_pnet_find_alt_roce(struct smc_link_group *lgr,
853 			    struct smc_init_info *ini,
854 			    struct smc_ib_device *known_dev)
855 {
856 	_smc_pnet_find_roce_by_pnetid(lgr->pnet_id, ini, known_dev);
857 }
858 
859 /* if handshake network device belongs to a roce device, return its
860  * IB device and port
861  */
862 static void smc_pnet_find_rdma_dev(struct net_device *netdev,
863 				   struct smc_init_info *ini)
864 {
865 	struct smc_ib_device *ibdev;
866 
867 	mutex_lock(&smc_ib_devices.mutex);
868 	list_for_each_entry(ibdev, &smc_ib_devices.list, list) {
869 		struct net_device *ndev;
870 		int i;
871 
872 		for (i = 1; i <= SMC_MAX_PORTS; i++) {
873 			if (!rdma_is_port_valid(ibdev->ibdev, i))
874 				continue;
875 			if (!ibdev->ibdev->ops.get_netdev)
876 				continue;
877 			ndev = ibdev->ibdev->ops.get_netdev(ibdev->ibdev, i);
878 			if (!ndev)
879 				continue;
880 			dev_put(ndev);
881 			if (netdev == ndev &&
882 			    smc_ib_port_active(ibdev, i) &&
883 			    !test_bit(i - 1, ibdev->ports_going_away) &&
884 			    !smc_ib_determine_gid(ibdev, i, ini->vlan_id,
885 						  ini->ib_gid, NULL)) {
886 				ini->ib_dev = ibdev;
887 				ini->ib_port = i;
888 				break;
889 			}
890 		}
891 	}
892 	mutex_unlock(&smc_ib_devices.mutex);
893 }
894 
895 /* Determine the corresponding IB device port based on the hardware PNETID.
896  * Searching stops at the first matching active IB device port with vlan_id
897  * configured.
898  * If nothing found, check pnetid table.
899  * If nothing found, try to use handshake device
900  */
901 static void smc_pnet_find_roce_by_pnetid(struct net_device *ndev,
902 					 struct smc_init_info *ini)
903 {
904 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
905 
906 	ndev = pnet_find_base_ndev(ndev);
907 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
908 				   ndev_pnetid) &&
909 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid)) {
910 		smc_pnet_find_rdma_dev(ndev, ini);
911 		return; /* pnetid could not be determined */
912 	}
913 	_smc_pnet_find_roce_by_pnetid(ndev_pnetid, ini, NULL);
914 }
915 
916 static void smc_pnet_find_ism_by_pnetid(struct net_device *ndev,
917 					struct smc_init_info *ini)
918 {
919 	u8 ndev_pnetid[SMC_MAX_PNETID_LEN];
920 	struct smcd_dev *ismdev;
921 
922 	ndev = pnet_find_base_ndev(ndev);
923 	if (smc_pnetid_by_dev_port(ndev->dev.parent, ndev->dev_port,
924 				   ndev_pnetid) &&
925 	    smc_pnet_find_ndev_pnetid_by_table(ndev, ndev_pnetid))
926 		return; /* pnetid could not be determined */
927 
928 	mutex_lock(&smcd_dev_list.mutex);
929 	list_for_each_entry(ismdev, &smcd_dev_list.list, list) {
930 		if (smc_pnet_match(ismdev->pnetid, ndev_pnetid) &&
931 		    !ismdev->going_away) {
932 			ini->ism_dev = ismdev;
933 			break;
934 		}
935 	}
936 	mutex_unlock(&smcd_dev_list.mutex);
937 }
938 
939 /* PNET table analysis for a given sock:
940  * determine ib_device and port belonging to used internal TCP socket
941  * ethernet interface.
942  */
943 void smc_pnet_find_roce_resource(struct sock *sk, struct smc_init_info *ini)
944 {
945 	struct dst_entry *dst = sk_dst_get(sk);
946 
947 	ini->ib_dev = NULL;
948 	ini->ib_port = 0;
949 	if (!dst)
950 		goto out;
951 	if (!dst->dev)
952 		goto out_rel;
953 
954 	smc_pnet_find_roce_by_pnetid(dst->dev, ini);
955 
956 out_rel:
957 	dst_release(dst);
958 out:
959 	return;
960 }
961 
962 void smc_pnet_find_ism_resource(struct sock *sk, struct smc_init_info *ini)
963 {
964 	struct dst_entry *dst = sk_dst_get(sk);
965 
966 	ini->ism_dev = NULL;
967 	if (!dst)
968 		goto out;
969 	if (!dst->dev)
970 		goto out_rel;
971 
972 	smc_pnet_find_ism_by_pnetid(dst->dev, ini);
973 
974 out_rel:
975 	dst_release(dst);
976 out:
977 	return;
978 }
979 
980 /* Lookup and apply a pnet table entry to the given ib device.
981  */
982 int smc_pnetid_by_table_ib(struct smc_ib_device *smcibdev, u8 ib_port)
983 {
984 	char *ib_name = smcibdev->ibdev->name;
985 	struct smc_pnettable *pnettable;
986 	struct smc_pnetentry *tmp_pe;
987 	struct smc_net *sn;
988 	int rc = -ENOENT;
989 
990 	/* get pnettable for init namespace */
991 	sn = net_generic(&init_net, smc_net_id);
992 	pnettable = &sn->pnettable;
993 
994 	read_lock(&pnettable->lock);
995 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
996 		if (tmp_pe->type == SMC_PNET_IB &&
997 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX) &&
998 		    tmp_pe->ib_port == ib_port) {
999 			smc_pnet_apply_ib(smcibdev, ib_port, tmp_pe->pnet_name);
1000 			rc = 0;
1001 			break;
1002 		}
1003 	}
1004 	read_unlock(&pnettable->lock);
1005 
1006 	return rc;
1007 }
1008 
1009 /* Lookup and apply a pnet table entry to the given smcd device.
1010  */
1011 int smc_pnetid_by_table_smcd(struct smcd_dev *smcddev)
1012 {
1013 	const char *ib_name = dev_name(&smcddev->dev);
1014 	struct smc_pnettable *pnettable;
1015 	struct smc_pnetentry *tmp_pe;
1016 	struct smc_net *sn;
1017 	int rc = -ENOENT;
1018 
1019 	/* get pnettable for init namespace */
1020 	sn = net_generic(&init_net, smc_net_id);
1021 	pnettable = &sn->pnettable;
1022 
1023 	read_lock(&pnettable->lock);
1024 	list_for_each_entry(tmp_pe, &pnettable->pnetlist, list) {
1025 		if (tmp_pe->type == SMC_PNET_IB &&
1026 		    !strncmp(tmp_pe->ib_name, ib_name, IB_DEVICE_NAME_MAX)) {
1027 			smc_pnet_apply_smcd(smcddev, tmp_pe->pnet_name);
1028 			rc = 0;
1029 			break;
1030 		}
1031 	}
1032 	read_unlock(&pnettable->lock);
1033 
1034 	return rc;
1035 }
1036