1 /*
2  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms and conditions of the GNU General Public License,
6  * version 2, as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope it will be useful, but WITHOUT
9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
11  * more details.
12  *
13  * You should have received a copy of the GNU General Public License along with
14  * this program; if not, write to the Free Software Foundation, Inc.,
15  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
16  *
17  * Maintained at www.Open-FCoE.org
18  */
19 
20 #include <linux/types.h>
21 #include <linux/module.h>
22 #include <linux/kernel.h>
23 #include <linux/list.h>
24 #include <linux/netdevice.h>
25 #include <linux/errno.h>
26 #include <linux/crc32.h>
27 #include <scsi/libfcoe.h>
28 
29 #include "libfcoe.h"
30 
31 MODULE_AUTHOR("Open-FCoE.org");
32 MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
33 MODULE_LICENSE("GPL v2");
34 
35 static int fcoe_transport_create(const char *, struct kernel_param *);
36 static int fcoe_transport_destroy(const char *, struct kernel_param *);
37 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp);
38 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *device);
39 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *device);
40 static int fcoe_transport_enable(const char *, struct kernel_param *);
41 static int fcoe_transport_disable(const char *, struct kernel_param *);
42 static int libfcoe_device_notification(struct notifier_block *notifier,
43 				    ulong event, void *ptr);
44 
45 static LIST_HEAD(fcoe_transports);
46 static DEFINE_MUTEX(ft_mutex);
47 static LIST_HEAD(fcoe_netdevs);
48 static DEFINE_MUTEX(fn_mutex);
49 
50 unsigned int libfcoe_debug_logging;
51 module_param_named(debug_logging, libfcoe_debug_logging, int, S_IRUGO|S_IWUSR);
52 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
53 
54 module_param_call(show, NULL, fcoe_transport_show, NULL, S_IRUSR);
55 __MODULE_PARM_TYPE(show, "string");
56 MODULE_PARM_DESC(show, " Show attached FCoE transports");
57 
58 module_param_call(create, fcoe_transport_create, NULL,
59 		  (void *)FIP_MODE_FABRIC, S_IWUSR);
60 __MODULE_PARM_TYPE(create, "string");
61 MODULE_PARM_DESC(create, " Creates fcoe instance on a ethernet interface");
62 
63 module_param_call(create_vn2vn, fcoe_transport_create, NULL,
64 		  (void *)FIP_MODE_VN2VN, S_IWUSR);
65 __MODULE_PARM_TYPE(create_vn2vn, "string");
66 MODULE_PARM_DESC(create_vn2vn, " Creates a VN_node to VN_node FCoE instance "
67 		 "on an Ethernet interface");
68 
69 module_param_call(destroy, fcoe_transport_destroy, NULL, NULL, S_IWUSR);
70 __MODULE_PARM_TYPE(destroy, "string");
71 MODULE_PARM_DESC(destroy, " Destroys fcoe instance on a ethernet interface");
72 
73 module_param_call(enable, fcoe_transport_enable, NULL, NULL, S_IWUSR);
74 __MODULE_PARM_TYPE(enable, "string");
75 MODULE_PARM_DESC(enable, " Enables fcoe on a ethernet interface.");
76 
77 module_param_call(disable, fcoe_transport_disable, NULL, NULL, S_IWUSR);
78 __MODULE_PARM_TYPE(disable, "string");
79 MODULE_PARM_DESC(disable, " Disables fcoe on a ethernet interface.");
80 
81 /* notification function for packets from net device */
82 static struct notifier_block libfcoe_notifier = {
83 	.notifier_call = libfcoe_device_notification,
84 };
85 
__fcoe_get_lesb(struct fc_lport * lport,struct fc_els_lesb * fc_lesb,struct net_device * netdev)86 void __fcoe_get_lesb(struct fc_lport *lport,
87 		     struct fc_els_lesb *fc_lesb,
88 		     struct net_device *netdev)
89 {
90 	unsigned int cpu;
91 	u32 lfc, vlfc, mdac;
92 	struct fcoe_dev_stats *devst;
93 	struct fcoe_fc_els_lesb *lesb;
94 	struct rtnl_link_stats64 temp;
95 
96 	lfc = 0;
97 	vlfc = 0;
98 	mdac = 0;
99 	lesb = (struct fcoe_fc_els_lesb *)fc_lesb;
100 	memset(lesb, 0, sizeof(*lesb));
101 	for_each_possible_cpu(cpu) {
102 		devst = per_cpu_ptr(lport->dev_stats, cpu);
103 		lfc += devst->LinkFailureCount;
104 		vlfc += devst->VLinkFailureCount;
105 		mdac += devst->MissDiscAdvCount;
106 	}
107 	lesb->lesb_link_fail = htonl(lfc);
108 	lesb->lesb_vlink_fail = htonl(vlfc);
109 	lesb->lesb_miss_fka = htonl(mdac);
110 	lesb->lesb_fcs_error =
111 			htonl(dev_get_stats(netdev, &temp)->rx_crc_errors);
112 }
113 EXPORT_SYMBOL_GPL(__fcoe_get_lesb);
114 
fcoe_wwn_to_str(u64 wwn,char * buf,int len)115 void fcoe_wwn_to_str(u64 wwn, char *buf, int len)
116 {
117 	u8 wwpn[8];
118 
119 	u64_to_wwn(wwn, wwpn);
120 	snprintf(buf, len, "%02x%02x%02x%02x%02x%02x%02x%02x",
121 		 wwpn[0], wwpn[1], wwpn[2], wwpn[3],
122 		 wwpn[4], wwpn[5], wwpn[6], wwpn[7]);
123 }
124 EXPORT_SYMBOL_GPL(fcoe_wwn_to_str);
125 
126 /**
127  * fcoe_validate_vport_create() - Validate a vport before creating it
128  * @vport: NPIV port to be created
129  *
130  * This routine is meant to add validation for a vport before creating it
131  * via fcoe_vport_create().
132  * Current validations are:
133  *      - WWPN supplied is unique for given lport
134  */
fcoe_validate_vport_create(struct fc_vport * vport)135 int fcoe_validate_vport_create(struct fc_vport *vport)
136 {
137 	struct Scsi_Host *shost = vport_to_shost(vport);
138 	struct fc_lport *n_port = shost_priv(shost);
139 	struct fc_lport *vn_port;
140 	int rc = 0;
141 	char buf[32];
142 
143 	mutex_lock(&n_port->lp_mutex);
144 
145 	fcoe_wwn_to_str(vport->port_name, buf, sizeof(buf));
146 	/* Check if the wwpn is not same as that of the lport */
147 	if (!memcmp(&n_port->wwpn, &vport->port_name, sizeof(u64))) {
148 		LIBFCOE_TRANSPORT_DBG("vport WWPN 0x%s is same as that of the "
149 				      "base port WWPN\n", buf);
150 		rc = -EINVAL;
151 		goto out;
152 	}
153 
154 	/* Check if there is any existing vport with same wwpn */
155 	list_for_each_entry(vn_port, &n_port->vports, list) {
156 		if (!memcmp(&vn_port->wwpn, &vport->port_name, sizeof(u64))) {
157 			LIBFCOE_TRANSPORT_DBG("vport with given WWPN 0x%s "
158 					      "already exists\n", buf);
159 			rc = -EINVAL;
160 			break;
161 		}
162 	}
163 out:
164 	mutex_unlock(&n_port->lp_mutex);
165 	return rc;
166 }
167 EXPORT_SYMBOL_GPL(fcoe_validate_vport_create);
168 
169 /**
170  * fcoe_get_wwn() - Get the world wide name from LLD if it supports it
171  * @netdev: the associated net device
172  * @wwn: the output WWN
173  * @type: the type of WWN (WWPN or WWNN)
174  *
175  * Returns: 0 for success
176  */
fcoe_get_wwn(struct net_device * netdev,u64 * wwn,int type)177 int fcoe_get_wwn(struct net_device *netdev, u64 *wwn, int type)
178 {
179 	const struct net_device_ops *ops = netdev->netdev_ops;
180 
181 	if (ops->ndo_fcoe_get_wwn)
182 		return ops->ndo_fcoe_get_wwn(netdev, wwn, type);
183 	return -EINVAL;
184 }
185 EXPORT_SYMBOL_GPL(fcoe_get_wwn);
186 
187 /**
188  * fcoe_fc_crc() - Calculates the CRC for a given frame
189  * @fp: The frame to be checksumed
190  *
191  * This uses crc32() routine to calculate the CRC for a frame
192  *
193  * Return: The 32 bit CRC value
194  */
fcoe_fc_crc(struct fc_frame * fp)195 u32 fcoe_fc_crc(struct fc_frame *fp)
196 {
197 	struct sk_buff *skb = fp_skb(fp);
198 	struct skb_frag_struct *frag;
199 	unsigned char *data;
200 	unsigned long off, len, clen;
201 	u32 crc;
202 	unsigned i;
203 
204 	crc = crc32(~0, skb->data, skb_headlen(skb));
205 
206 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
207 		frag = &skb_shinfo(skb)->frags[i];
208 		off = frag->page_offset;
209 		len = skb_frag_size(frag);
210 		while (len > 0) {
211 			clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
212 			data = kmap_atomic(
213 				skb_frag_page(frag) + (off >> PAGE_SHIFT));
214 			crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
215 			kunmap_atomic(data);
216 			off += clen;
217 			len -= clen;
218 		}
219 	}
220 	return crc;
221 }
222 EXPORT_SYMBOL_GPL(fcoe_fc_crc);
223 
224 /**
225  * fcoe_start_io() - Start FCoE I/O
226  * @skb: The packet to be transmitted
227  *
228  * This routine is called from the net device to start transmitting
229  * FCoE packets.
230  *
231  * Returns: 0 for success
232  */
fcoe_start_io(struct sk_buff * skb)233 int fcoe_start_io(struct sk_buff *skb)
234 {
235 	struct sk_buff *nskb;
236 	int rc;
237 
238 	nskb = skb_clone(skb, GFP_ATOMIC);
239 	if (!nskb)
240 		return -ENOMEM;
241 	rc = dev_queue_xmit(nskb);
242 	if (rc != 0)
243 		return rc;
244 	kfree_skb(skb);
245 	return 0;
246 }
247 EXPORT_SYMBOL_GPL(fcoe_start_io);
248 
249 
250 /**
251  * fcoe_clean_pending_queue() - Dequeue a skb and free it
252  * @lport: The local port to dequeue a skb on
253  */
fcoe_clean_pending_queue(struct fc_lport * lport)254 void fcoe_clean_pending_queue(struct fc_lport *lport)
255 {
256 	struct fcoe_port  *port = lport_priv(lport);
257 	struct sk_buff *skb;
258 
259 	spin_lock_bh(&port->fcoe_pending_queue.lock);
260 	while ((skb = __skb_dequeue(&port->fcoe_pending_queue)) != NULL) {
261 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
262 		kfree_skb(skb);
263 		spin_lock_bh(&port->fcoe_pending_queue.lock);
264 	}
265 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
266 }
267 EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue);
268 
269 /**
270  * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
271  * @lport: The local port whose backlog is to be cleared
272  *
273  * This empties the wait_queue, dequeues the head of the wait_queue queue
274  * and calls fcoe_start_io() for each packet. If all skb have been
275  * transmitted it returns the qlen. If an error occurs it restores
276  * wait_queue (to try again later) and returns -1.
277  *
278  * The wait_queue is used when the skb transmit fails. The failed skb
279  * will go in the wait_queue which will be emptied by the timer function or
280  * by the next skb transmit.
281  */
fcoe_check_wait_queue(struct fc_lport * lport,struct sk_buff * skb)282 void fcoe_check_wait_queue(struct fc_lport *lport, struct sk_buff *skb)
283 {
284 	struct fcoe_port *port = lport_priv(lport);
285 	int rc;
286 
287 	spin_lock_bh(&port->fcoe_pending_queue.lock);
288 
289 	if (skb)
290 		__skb_queue_tail(&port->fcoe_pending_queue, skb);
291 
292 	if (port->fcoe_pending_queue_active)
293 		goto out;
294 	port->fcoe_pending_queue_active = 1;
295 
296 	while (port->fcoe_pending_queue.qlen) {
297 		/* keep qlen > 0 until fcoe_start_io succeeds */
298 		port->fcoe_pending_queue.qlen++;
299 		skb = __skb_dequeue(&port->fcoe_pending_queue);
300 
301 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
302 		rc = fcoe_start_io(skb);
303 		spin_lock_bh(&port->fcoe_pending_queue.lock);
304 
305 		if (rc) {
306 			__skb_queue_head(&port->fcoe_pending_queue, skb);
307 			/* undo temporary increment above */
308 			port->fcoe_pending_queue.qlen--;
309 			break;
310 		}
311 		/* undo temporary increment above */
312 		port->fcoe_pending_queue.qlen--;
313 	}
314 
315 	if (port->fcoe_pending_queue.qlen < port->min_queue_depth)
316 		lport->qfull = 0;
317 	if (port->fcoe_pending_queue.qlen && !timer_pending(&port->timer))
318 		mod_timer(&port->timer, jiffies + 2);
319 	port->fcoe_pending_queue_active = 0;
320 out:
321 	if (port->fcoe_pending_queue.qlen > port->max_queue_depth)
322 		lport->qfull = 1;
323 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
324 }
325 EXPORT_SYMBOL_GPL(fcoe_check_wait_queue);
326 
327 /**
328  * fcoe_queue_timer() - The fcoe queue timer
329  * @lport: The local port
330  *
331  * Calls fcoe_check_wait_queue on timeout
332  */
fcoe_queue_timer(ulong lport)333 void fcoe_queue_timer(ulong lport)
334 {
335 	fcoe_check_wait_queue((struct fc_lport *)lport, NULL);
336 }
337 EXPORT_SYMBOL_GPL(fcoe_queue_timer);
338 
339 /**
340  * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
341  * @skb:  The packet to be transmitted
342  * @tlen: The total length of the trailer
343  * @fps:  The fcoe context
344  *
345  * This routine allocates a page for frame trailers. The page is re-used if
346  * there is enough room left on it for the current trailer. If there isn't
347  * enough buffer left a new page is allocated for the trailer. Reference to
348  * the page from this function as well as the skbs using the page fragments
349  * ensure that the page is freed at the appropriate time.
350  *
351  * Returns: 0 for success
352  */
fcoe_get_paged_crc_eof(struct sk_buff * skb,int tlen,struct fcoe_percpu_s * fps)353 int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen,
354 			   struct fcoe_percpu_s *fps)
355 {
356 	struct page *page;
357 
358 	page = fps->crc_eof_page;
359 	if (!page) {
360 		page = alloc_page(GFP_ATOMIC);
361 		if (!page)
362 			return -ENOMEM;
363 
364 		fps->crc_eof_page = page;
365 		fps->crc_eof_offset = 0;
366 	}
367 
368 	get_page(page);
369 	skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page,
370 			   fps->crc_eof_offset, tlen);
371 	skb->len += tlen;
372 	skb->data_len += tlen;
373 	skb->truesize += tlen;
374 	fps->crc_eof_offset += sizeof(struct fcoe_crc_eof);
375 
376 	if (fps->crc_eof_offset >= PAGE_SIZE) {
377 		fps->crc_eof_page = NULL;
378 		fps->crc_eof_offset = 0;
379 		put_page(page);
380 	}
381 
382 	return 0;
383 }
384 EXPORT_SYMBOL_GPL(fcoe_get_paged_crc_eof);
385 
386 /**
387  * fcoe_transport_lookup - find an fcoe transport that matches a netdev
388  * @netdev: The netdev to look for from all attached transports
389  *
390  * Returns : ptr to the fcoe transport that supports this netdev or NULL
391  * if not found.
392  *
393  * The ft_mutex should be held when this is called
394  */
fcoe_transport_lookup(struct net_device * netdev)395 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *netdev)
396 {
397 	struct fcoe_transport *ft = NULL;
398 
399 	list_for_each_entry(ft, &fcoe_transports, list)
400 		if (ft->match && ft->match(netdev))
401 			return ft;
402 	return NULL;
403 }
404 
405 /**
406  * fcoe_transport_attach - Attaches an FCoE transport
407  * @ft: The fcoe transport to be attached
408  *
409  * Returns : 0 for success
410  */
fcoe_transport_attach(struct fcoe_transport * ft)411 int fcoe_transport_attach(struct fcoe_transport *ft)
412 {
413 	int rc = 0;
414 
415 	mutex_lock(&ft_mutex);
416 	if (ft->attached) {
417 		LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
418 				       ft->name);
419 		rc = -EEXIST;
420 		goto out_attach;
421 	}
422 
423 	/* Add default transport to the tail */
424 	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
425 		list_add(&ft->list, &fcoe_transports);
426 	else
427 		list_add_tail(&ft->list, &fcoe_transports);
428 
429 	ft->attached = true;
430 	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);
431 
432 out_attach:
433 	mutex_unlock(&ft_mutex);
434 	return rc;
435 }
436 EXPORT_SYMBOL(fcoe_transport_attach);
437 
438 /**
439  * fcoe_transport_detach - Detaches an FCoE transport
440  * @ft: The fcoe transport to be attached
441  *
442  * Returns : 0 for success
443  */
fcoe_transport_detach(struct fcoe_transport * ft)444 int fcoe_transport_detach(struct fcoe_transport *ft)
445 {
446 	int rc = 0;
447 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
448 
449 	mutex_lock(&ft_mutex);
450 	if (!ft->attached) {
451 		LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
452 			ft->name);
453 		rc = -ENODEV;
454 		goto out_attach;
455 	}
456 
457 	/* remove netdev mapping for this transport as it is going away */
458 	mutex_lock(&fn_mutex);
459 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
460 		if (nm->ft == ft) {
461 			LIBFCOE_TRANSPORT_DBG("transport %s going away, "
462 				"remove its netdev mapping for %s\n",
463 				ft->name, nm->netdev->name);
464 			list_del(&nm->list);
465 			kfree(nm);
466 		}
467 	}
468 	mutex_unlock(&fn_mutex);
469 
470 	list_del(&ft->list);
471 	ft->attached = false;
472 	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);
473 
474 out_attach:
475 	mutex_unlock(&ft_mutex);
476 	return rc;
477 
478 }
479 EXPORT_SYMBOL(fcoe_transport_detach);
480 
fcoe_transport_show(char * buffer,const struct kernel_param * kp)481 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp)
482 {
483 	int i, j;
484 	struct fcoe_transport *ft = NULL;
485 
486 	i = j = sprintf(buffer, "Attached FCoE transports:");
487 	mutex_lock(&ft_mutex);
488 	list_for_each_entry(ft, &fcoe_transports, list) {
489 		if (i >= PAGE_SIZE - IFNAMSIZ)
490 			break;
491 		i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
492 	}
493 	mutex_unlock(&ft_mutex);
494 	if (i == j)
495 		i += snprintf(&buffer[i], IFNAMSIZ, "none");
496 	return i;
497 }
498 
fcoe_transport_init(void)499 static int __init fcoe_transport_init(void)
500 {
501 	register_netdevice_notifier(&libfcoe_notifier);
502 	return 0;
503 }
504 
fcoe_transport_exit(void)505 static int __exit fcoe_transport_exit(void)
506 {
507 	struct fcoe_transport *ft;
508 
509 	unregister_netdevice_notifier(&libfcoe_notifier);
510 	mutex_lock(&ft_mutex);
511 	list_for_each_entry(ft, &fcoe_transports, list)
512 		printk(KERN_ERR "FCoE transport %s is still attached!\n",
513 		      ft->name);
514 	mutex_unlock(&ft_mutex);
515 	return 0;
516 }
517 
518 
fcoe_add_netdev_mapping(struct net_device * netdev,struct fcoe_transport * ft)519 static int fcoe_add_netdev_mapping(struct net_device *netdev,
520 					struct fcoe_transport *ft)
521 {
522 	struct fcoe_netdev_mapping *nm;
523 
524 	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
525 	if (!nm) {
526 		printk(KERN_ERR "Unable to allocate netdev_mapping");
527 		return -ENOMEM;
528 	}
529 
530 	nm->netdev = netdev;
531 	nm->ft = ft;
532 
533 	mutex_lock(&fn_mutex);
534 	list_add(&nm->list, &fcoe_netdevs);
535 	mutex_unlock(&fn_mutex);
536 	return 0;
537 }
538 
539 
fcoe_del_netdev_mapping(struct net_device * netdev)540 static void fcoe_del_netdev_mapping(struct net_device *netdev)
541 {
542 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
543 
544 	mutex_lock(&fn_mutex);
545 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
546 		if (nm->netdev == netdev) {
547 			list_del(&nm->list);
548 			kfree(nm);
549 			mutex_unlock(&fn_mutex);
550 			return;
551 		}
552 	}
553 	mutex_unlock(&fn_mutex);
554 }
555 
556 
557 /**
558  * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
559  * it was created
560  *
561  * Returns : ptr to the fcoe transport that supports this netdev or NULL
562  * if not found.
563  *
564  * The ft_mutex should be held when this is called
565  */
fcoe_netdev_map_lookup(struct net_device * netdev)566 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *netdev)
567 {
568 	struct fcoe_transport *ft = NULL;
569 	struct fcoe_netdev_mapping *nm;
570 
571 	mutex_lock(&fn_mutex);
572 	list_for_each_entry(nm, &fcoe_netdevs, list) {
573 		if (netdev == nm->netdev) {
574 			ft = nm->ft;
575 			mutex_unlock(&fn_mutex);
576 			return ft;
577 		}
578 	}
579 
580 	mutex_unlock(&fn_mutex);
581 	return NULL;
582 }
583 
584 /**
585  * fcoe_if_to_netdev() - Parse a name buffer to get a net device
586  * @buffer: The name of the net device
587  *
588  * Returns: NULL or a ptr to net_device
589  */
fcoe_if_to_netdev(const char * buffer)590 static struct net_device *fcoe_if_to_netdev(const char *buffer)
591 {
592 	char *cp;
593 	char ifname[IFNAMSIZ + 2];
594 
595 	if (buffer) {
596 		strlcpy(ifname, buffer, IFNAMSIZ);
597 		cp = ifname + strlen(ifname);
598 		while (--cp >= ifname && *cp == '\n')
599 			*cp = '\0';
600 		return dev_get_by_name(&init_net, ifname);
601 	}
602 	return NULL;
603 }
604 
605 /**
606  * libfcoe_device_notification() - Handler for net device events
607  * @notifier: The context of the notification
608  * @event:    The type of event
609  * @ptr:      The net device that the event was on
610  *
611  * This function is called by the Ethernet driver in case of link change event.
612  *
613  * Returns: 0 for success
614  */
libfcoe_device_notification(struct notifier_block * notifier,ulong event,void * ptr)615 static int libfcoe_device_notification(struct notifier_block *notifier,
616 				    ulong event, void *ptr)
617 {
618 	struct net_device *netdev = ptr;
619 
620 	switch (event) {
621 	case NETDEV_UNREGISTER:
622 		LIBFCOE_TRANSPORT_DBG("NETDEV_UNREGISTER %s\n",
623 				      netdev->name);
624 		fcoe_del_netdev_mapping(netdev);
625 		break;
626 	}
627 	return NOTIFY_OK;
628 }
629 
630 
631 /**
632  * fcoe_transport_create() - Create a fcoe interface
633  * @buffer: The name of the Ethernet interface to create on
634  * @kp:	    The associated kernel param
635  *
636  * Called from sysfs. This holds the ft_mutex while calling the
637  * registered fcoe transport's create function.
638  *
639  * Returns: 0 for success
640  */
fcoe_transport_create(const char * buffer,struct kernel_param * kp)641 static int fcoe_transport_create(const char *buffer, struct kernel_param *kp)
642 {
643 	int rc = -ENODEV;
644 	struct net_device *netdev = NULL;
645 	struct fcoe_transport *ft = NULL;
646 	enum fip_state fip_mode = (enum fip_state)(long)kp->arg;
647 
648 	mutex_lock(&ft_mutex);
649 
650 	netdev = fcoe_if_to_netdev(buffer);
651 	if (!netdev) {
652 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
653 		goto out_nodev;
654 	}
655 
656 	ft = fcoe_netdev_map_lookup(netdev);
657 	if (ft) {
658 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
659 				      "FCoE instance on %s.\n",
660 				      ft->name, netdev->name);
661 		rc = -EEXIST;
662 		goto out_putdev;
663 	}
664 
665 	ft = fcoe_transport_lookup(netdev);
666 	if (!ft) {
667 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
668 				      netdev->name);
669 		goto out_putdev;
670 	}
671 
672 	rc = fcoe_add_netdev_mapping(netdev, ft);
673 	if (rc) {
674 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
675 				      "for FCoE transport %s for %s.\n",
676 				      ft->name, netdev->name);
677 		goto out_putdev;
678 	}
679 
680 	/* pass to transport create */
681 	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
682 	if (rc)
683 		fcoe_del_netdev_mapping(netdev);
684 
685 	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
686 			      ft->name, (rc) ? "failed" : "succeeded",
687 			      netdev->name);
688 
689 out_putdev:
690 	dev_put(netdev);
691 out_nodev:
692 	mutex_unlock(&ft_mutex);
693 	return rc;
694 }
695 
696 /**
697  * fcoe_transport_destroy() - Destroy a FCoE interface
698  * @buffer: The name of the Ethernet interface to be destroyed
699  * @kp:	    The associated kernel parameter
700  *
701  * Called from sysfs. This holds the ft_mutex while calling the
702  * registered fcoe transport's destroy function.
703  *
704  * Returns: 0 for success
705  */
fcoe_transport_destroy(const char * buffer,struct kernel_param * kp)706 static int fcoe_transport_destroy(const char *buffer, struct kernel_param *kp)
707 {
708 	int rc = -ENODEV;
709 	struct net_device *netdev = NULL;
710 	struct fcoe_transport *ft = NULL;
711 
712 	mutex_lock(&ft_mutex);
713 
714 	netdev = fcoe_if_to_netdev(buffer);
715 	if (!netdev) {
716 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
717 		goto out_nodev;
718 	}
719 
720 	ft = fcoe_netdev_map_lookup(netdev);
721 	if (!ft) {
722 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
723 				      netdev->name);
724 		goto out_putdev;
725 	}
726 
727 	/* pass to transport destroy */
728 	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
729 	fcoe_del_netdev_mapping(netdev);
730 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
731 			      ft->name, (rc) ? "failed" : "succeeded",
732 			      netdev->name);
733 
734 out_putdev:
735 	dev_put(netdev);
736 out_nodev:
737 	mutex_unlock(&ft_mutex);
738 	return rc;
739 }
740 
741 /**
742  * fcoe_transport_disable() - Disables a FCoE interface
743  * @buffer: The name of the Ethernet interface to be disabled
744  * @kp:	    The associated kernel parameter
745  *
746  * Called from sysfs.
747  *
748  * Returns: 0 for success
749  */
fcoe_transport_disable(const char * buffer,struct kernel_param * kp)750 static int fcoe_transport_disable(const char *buffer, struct kernel_param *kp)
751 {
752 	int rc = -ENODEV;
753 	struct net_device *netdev = NULL;
754 	struct fcoe_transport *ft = NULL;
755 
756 	mutex_lock(&ft_mutex);
757 
758 	netdev = fcoe_if_to_netdev(buffer);
759 	if (!netdev)
760 		goto out_nodev;
761 
762 	ft = fcoe_netdev_map_lookup(netdev);
763 	if (!ft)
764 		goto out_putdev;
765 
766 	rc = ft->disable ? ft->disable(netdev) : -ENODEV;
767 
768 out_putdev:
769 	dev_put(netdev);
770 out_nodev:
771 	mutex_unlock(&ft_mutex);
772 
773 	if (rc == -ERESTARTSYS)
774 		return restart_syscall();
775 	else
776 		return rc;
777 }
778 
779 /**
780  * fcoe_transport_enable() - Enables a FCoE interface
781  * @buffer: The name of the Ethernet interface to be enabled
782  * @kp:     The associated kernel parameter
783  *
784  * Called from sysfs.
785  *
786  * Returns: 0 for success
787  */
fcoe_transport_enable(const char * buffer,struct kernel_param * kp)788 static int fcoe_transport_enable(const char *buffer, struct kernel_param *kp)
789 {
790 	int rc = -ENODEV;
791 	struct net_device *netdev = NULL;
792 	struct fcoe_transport *ft = NULL;
793 
794 	mutex_lock(&ft_mutex);
795 
796 	netdev = fcoe_if_to_netdev(buffer);
797 	if (!netdev)
798 		goto out_nodev;
799 
800 	ft = fcoe_netdev_map_lookup(netdev);
801 	if (!ft)
802 		goto out_putdev;
803 
804 	rc = ft->enable ? ft->enable(netdev) : -ENODEV;
805 
806 out_putdev:
807 	dev_put(netdev);
808 out_nodev:
809 	mutex_unlock(&ft_mutex);
810 	return rc;
811 }
812 
813 /**
814  * libfcoe_init() - Initialization routine for libfcoe.ko
815  */
libfcoe_init(void)816 static int __init libfcoe_init(void)
817 {
818 	fcoe_transport_init();
819 
820 	return 0;
821 }
822 module_init(libfcoe_init);
823 
824 /**
825  * libfcoe_exit() - Tear down libfcoe.ko
826  */
libfcoe_exit(void)827 static void __exit libfcoe_exit(void)
828 {
829 	fcoe_transport_exit();
830 }
831 module_exit(libfcoe_exit);
832