1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
4  *
5  * Maintained at www.Open-FCoE.org
6  */
7 
8 #include <linux/types.h>
9 #include <linux/module.h>
10 #include <linux/kernel.h>
11 #include <linux/list.h>
12 #include <linux/netdevice.h>
13 #include <linux/errno.h>
14 #include <linux/crc32.h>
15 #include <scsi/libfcoe.h>
16 
17 #include "libfcoe.h"
18 
19 MODULE_AUTHOR("Open-FCoE.org");
20 MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
21 MODULE_LICENSE("GPL v2");
22 
23 static int fcoe_transport_create(const char *, const struct kernel_param *);
24 static int fcoe_transport_destroy(const char *, const struct kernel_param *);
25 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp);
26 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *device);
27 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *device);
28 static int fcoe_transport_enable(const char *, const struct kernel_param *);
29 static int fcoe_transport_disable(const char *, const struct kernel_param *);
30 static int libfcoe_device_notification(struct notifier_block *notifier,
31 				    ulong event, void *ptr);
32 
33 static LIST_HEAD(fcoe_transports);
34 static DEFINE_MUTEX(ft_mutex);
35 static LIST_HEAD(fcoe_netdevs);
36 static DEFINE_MUTEX(fn_mutex);
37 
38 unsigned int libfcoe_debug_logging;
39 module_param_named(debug_logging, libfcoe_debug_logging, int, S_IRUGO|S_IWUSR);
40 MODULE_PARM_DESC(debug_logging, "a bit mask of logging levels");
41 
42 module_param_call(show, NULL, fcoe_transport_show, NULL, S_IRUSR);
43 __MODULE_PARM_TYPE(show, "string");
44 MODULE_PARM_DESC(show, " Show attached FCoE transports");
45 
46 module_param_call(create, fcoe_transport_create, NULL,
47 		  (void *)FIP_MODE_FABRIC, S_IWUSR);
48 __MODULE_PARM_TYPE(create, "string");
49 MODULE_PARM_DESC(create, " Creates fcoe instance on an ethernet interface");
50 
51 module_param_call(create_vn2vn, fcoe_transport_create, NULL,
52 		  (void *)FIP_MODE_VN2VN, S_IWUSR);
53 __MODULE_PARM_TYPE(create_vn2vn, "string");
54 MODULE_PARM_DESC(create_vn2vn, " Creates a VN_node to VN_node FCoE instance "
55 		 "on an Ethernet interface");
56 
57 module_param_call(destroy, fcoe_transport_destroy, NULL, NULL, S_IWUSR);
58 __MODULE_PARM_TYPE(destroy, "string");
59 MODULE_PARM_DESC(destroy, " Destroys fcoe instance on an ethernet interface");
60 
61 module_param_call(enable, fcoe_transport_enable, NULL, NULL, S_IWUSR);
62 __MODULE_PARM_TYPE(enable, "string");
63 MODULE_PARM_DESC(enable, " Enables fcoe on an ethernet interface.");
64 
65 module_param_call(disable, fcoe_transport_disable, NULL, NULL, S_IWUSR);
66 __MODULE_PARM_TYPE(disable, "string");
67 MODULE_PARM_DESC(disable, " Disables fcoe on an ethernet interface.");
68 
69 /* notification function for packets from net device */
70 static struct notifier_block libfcoe_notifier = {
71 	.notifier_call = libfcoe_device_notification,
72 };
73 
74 static const struct {
75 	u32 fc_port_speed;
76 #define SPEED_2000	2000
77 #define SPEED_4000	4000
78 #define SPEED_8000	8000
79 #define SPEED_16000	16000
80 #define SPEED_32000	32000
81 	u32 eth_port_speed;
82 } fcoe_port_speed_mapping[] = {
83 	{ FC_PORTSPEED_1GBIT,   SPEED_1000   },
84 	{ FC_PORTSPEED_2GBIT,   SPEED_2000   },
85 	{ FC_PORTSPEED_4GBIT,   SPEED_4000   },
86 	{ FC_PORTSPEED_8GBIT,   SPEED_8000   },
87 	{ FC_PORTSPEED_10GBIT,  SPEED_10000  },
88 	{ FC_PORTSPEED_16GBIT,  SPEED_16000  },
89 	{ FC_PORTSPEED_20GBIT,  SPEED_20000  },
90 	{ FC_PORTSPEED_25GBIT,  SPEED_25000  },
91 	{ FC_PORTSPEED_32GBIT,  SPEED_32000  },
92 	{ FC_PORTSPEED_40GBIT,  SPEED_40000  },
93 	{ FC_PORTSPEED_50GBIT,  SPEED_50000  },
94 	{ FC_PORTSPEED_100GBIT, SPEED_100000 },
95 };
96 
97 static inline u32 eth2fc_speed(u32 eth_port_speed)
98 {
99 	int i;
100 
101 	for (i = 0; i < ARRAY_SIZE(fcoe_port_speed_mapping); i++) {
102 		if (fcoe_port_speed_mapping[i].eth_port_speed == eth_port_speed)
103 			return fcoe_port_speed_mapping[i].fc_port_speed;
104 	}
105 
106 	return FC_PORTSPEED_UNKNOWN;
107 }
108 
109 /**
110  * fcoe_link_speed_update() - Update the supported and actual link speeds
111  * @lport: The local port to update speeds for
112  *
113  * Returns: 0 if the ethtool query was successful
114  *          -1 if the ethtool query failed
115  */
116 int fcoe_link_speed_update(struct fc_lport *lport)
117 {
118 	struct net_device *netdev = fcoe_get_netdev(lport);
119 	struct ethtool_link_ksettings ecmd;
120 
121 	if (!__ethtool_get_link_ksettings(netdev, &ecmd)) {
122 		lport->link_supported_speeds &= ~(FC_PORTSPEED_1GBIT  |
123 		                                  FC_PORTSPEED_10GBIT |
124 		                                  FC_PORTSPEED_20GBIT |
125 		                                  FC_PORTSPEED_40GBIT);
126 
127 		if (ecmd.link_modes.supported[0] & (
128 			    SUPPORTED_1000baseT_Half |
129 			    SUPPORTED_1000baseT_Full |
130 			    SUPPORTED_1000baseKX_Full))
131 			lport->link_supported_speeds |= FC_PORTSPEED_1GBIT;
132 
133 		if (ecmd.link_modes.supported[0] & (
134 			    SUPPORTED_10000baseT_Full   |
135 			    SUPPORTED_10000baseKX4_Full |
136 			    SUPPORTED_10000baseKR_Full  |
137 			    SUPPORTED_10000baseR_FEC))
138 			lport->link_supported_speeds |= FC_PORTSPEED_10GBIT;
139 
140 		if (ecmd.link_modes.supported[0] & (
141 			    SUPPORTED_20000baseMLD2_Full |
142 			    SUPPORTED_20000baseKR2_Full))
143 			lport->link_supported_speeds |= FC_PORTSPEED_20GBIT;
144 
145 		if (ecmd.link_modes.supported[0] & (
146 			    SUPPORTED_40000baseKR4_Full |
147 			    SUPPORTED_40000baseCR4_Full |
148 			    SUPPORTED_40000baseSR4_Full |
149 			    SUPPORTED_40000baseLR4_Full))
150 			lport->link_supported_speeds |= FC_PORTSPEED_40GBIT;
151 
152 		lport->link_speed = eth2fc_speed(ecmd.base.speed);
153 		return 0;
154 	}
155 	return -1;
156 }
157 EXPORT_SYMBOL_GPL(fcoe_link_speed_update);
158 
159 /**
160  * __fcoe_get_lesb() - Get the Link Error Status Block (LESB) for a given lport
161  * @lport: The local port to update speeds for
162  * @fc_lesb: Pointer to the LESB to be filled up
163  * @netdev: Pointer to the netdev that is associated with the lport
164  *
165  * Note, the Link Error Status Block (LESB) for FCoE is defined in FC-BB-6
166  * Clause 7.11 in v1.04.
167  */
168 void __fcoe_get_lesb(struct fc_lport *lport,
169 		     struct fc_els_lesb *fc_lesb,
170 		     struct net_device *netdev)
171 {
172 	unsigned int cpu;
173 	u32 lfc, vlfc, mdac;
174 	struct fc_stats *stats;
175 	struct fcoe_fc_els_lesb *lesb;
176 	struct rtnl_link_stats64 temp;
177 
178 	lfc = 0;
179 	vlfc = 0;
180 	mdac = 0;
181 	lesb = (struct fcoe_fc_els_lesb *)fc_lesb;
182 	memset(lesb, 0, sizeof(*lesb));
183 	for_each_possible_cpu(cpu) {
184 		stats = per_cpu_ptr(lport->stats, cpu);
185 		lfc += stats->LinkFailureCount;
186 		vlfc += stats->VLinkFailureCount;
187 		mdac += stats->MissDiscAdvCount;
188 	}
189 	lesb->lesb_link_fail = htonl(lfc);
190 	lesb->lesb_vlink_fail = htonl(vlfc);
191 	lesb->lesb_miss_fka = htonl(mdac);
192 	lesb->lesb_fcs_error =
193 			htonl(dev_get_stats(netdev, &temp)->rx_crc_errors);
194 }
195 EXPORT_SYMBOL_GPL(__fcoe_get_lesb);
196 
197 /**
198  * fcoe_get_lesb() - Fill the FCoE Link Error Status Block
199  * @lport: the local port
200  * @fc_lesb: the link error status block
201  */
202 void fcoe_get_lesb(struct fc_lport *lport,
203 			 struct fc_els_lesb *fc_lesb)
204 {
205 	struct net_device *netdev = fcoe_get_netdev(lport);
206 
207 	__fcoe_get_lesb(lport, fc_lesb, netdev);
208 }
209 EXPORT_SYMBOL_GPL(fcoe_get_lesb);
210 
211 /**
212  * fcoe_ctlr_get_lesb() - Get the Link Error Status Block (LESB) for a given
213  * fcoe controller device
214  * @ctlr_dev: The given fcoe controller device
215  *
216  */
217 void fcoe_ctlr_get_lesb(struct fcoe_ctlr_device *ctlr_dev)
218 {
219 	struct fcoe_ctlr *fip = fcoe_ctlr_device_priv(ctlr_dev);
220 	struct net_device *netdev = fcoe_get_netdev(fip->lp);
221 	struct fc_els_lesb *fc_lesb;
222 
223 	fc_lesb = (struct fc_els_lesb *)(&ctlr_dev->lesb);
224 	__fcoe_get_lesb(fip->lp, fc_lesb, netdev);
225 }
226 EXPORT_SYMBOL_GPL(fcoe_ctlr_get_lesb);
227 
228 void fcoe_wwn_to_str(u64 wwn, char *buf, int len)
229 {
230 	u8 wwpn[8];
231 
232 	u64_to_wwn(wwn, wwpn);
233 	snprintf(buf, len, "%02x%02x%02x%02x%02x%02x%02x%02x",
234 		 wwpn[0], wwpn[1], wwpn[2], wwpn[3],
235 		 wwpn[4], wwpn[5], wwpn[6], wwpn[7]);
236 }
237 EXPORT_SYMBOL_GPL(fcoe_wwn_to_str);
238 
239 /**
240  * fcoe_validate_vport_create() - Validate a vport before creating it
241  * @vport: NPIV port to be created
242  *
243  * This routine is meant to add validation for a vport before creating it
244  * via fcoe_vport_create().
245  * Current validations are:
246  *      - WWPN supplied is unique for given lport
247  */
248 int fcoe_validate_vport_create(struct fc_vport *vport)
249 {
250 	struct Scsi_Host *shost = vport_to_shost(vport);
251 	struct fc_lport *n_port = shost_priv(shost);
252 	struct fc_lport *vn_port;
253 	int rc = 0;
254 	char buf[32];
255 
256 	mutex_lock(&n_port->lp_mutex);
257 
258 	fcoe_wwn_to_str(vport->port_name, buf, sizeof(buf));
259 	/* Check if the wwpn is not same as that of the lport */
260 	if (!memcmp(&n_port->wwpn, &vport->port_name, sizeof(u64))) {
261 		LIBFCOE_TRANSPORT_DBG("vport WWPN 0x%s is same as that of the "
262 				      "base port WWPN\n", buf);
263 		rc = -EINVAL;
264 		goto out;
265 	}
266 
267 	/* Check if there is any existing vport with same wwpn */
268 	list_for_each_entry(vn_port, &n_port->vports, list) {
269 		if (!memcmp(&vn_port->wwpn, &vport->port_name, sizeof(u64))) {
270 			LIBFCOE_TRANSPORT_DBG("vport with given WWPN 0x%s "
271 					      "already exists\n", buf);
272 			rc = -EINVAL;
273 			break;
274 		}
275 	}
276 out:
277 	mutex_unlock(&n_port->lp_mutex);
278 	return rc;
279 }
280 EXPORT_SYMBOL_GPL(fcoe_validate_vport_create);
281 
282 /**
283  * fcoe_get_wwn() - Get the world wide name from LLD if it supports it
284  * @netdev: the associated net device
285  * @wwn: the output WWN
286  * @type: the type of WWN (WWPN or WWNN)
287  *
288  * Returns: 0 for success
289  */
290 int fcoe_get_wwn(struct net_device *netdev, u64 *wwn, int type)
291 {
292 	const struct net_device_ops *ops = netdev->netdev_ops;
293 
294 	if (ops->ndo_fcoe_get_wwn)
295 		return ops->ndo_fcoe_get_wwn(netdev, wwn, type);
296 	return -EINVAL;
297 }
298 EXPORT_SYMBOL_GPL(fcoe_get_wwn);
299 
300 /**
301  * fcoe_fc_crc() - Calculates the CRC for a given frame
302  * @fp: The frame to be checksumed
303  *
304  * This uses crc32() routine to calculate the CRC for a frame
305  *
306  * Return: The 32 bit CRC value
307  */
308 u32 fcoe_fc_crc(struct fc_frame *fp)
309 {
310 	struct sk_buff *skb = fp_skb(fp);
311 	skb_frag_t *frag;
312 	unsigned char *data;
313 	unsigned long off, len, clen;
314 	u32 crc;
315 	unsigned i;
316 
317 	crc = crc32(~0, skb->data, skb_headlen(skb));
318 
319 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
320 		frag = &skb_shinfo(skb)->frags[i];
321 		off = skb_frag_off(frag);
322 		len = skb_frag_size(frag);
323 		while (len > 0) {
324 			clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
325 			data = kmap_atomic(
326 				skb_frag_page(frag) + (off >> PAGE_SHIFT));
327 			crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
328 			kunmap_atomic(data);
329 			off += clen;
330 			len -= clen;
331 		}
332 	}
333 	return crc;
334 }
335 EXPORT_SYMBOL_GPL(fcoe_fc_crc);
336 
337 /**
338  * fcoe_start_io() - Start FCoE I/O
339  * @skb: The packet to be transmitted
340  *
341  * This routine is called from the net device to start transmitting
342  * FCoE packets.
343  *
344  * Returns: 0 for success
345  */
346 int fcoe_start_io(struct sk_buff *skb)
347 {
348 	struct sk_buff *nskb;
349 	int rc;
350 
351 	nskb = skb_clone(skb, GFP_ATOMIC);
352 	if (!nskb)
353 		return -ENOMEM;
354 	rc = dev_queue_xmit(nskb);
355 	if (rc != 0)
356 		return rc;
357 	kfree_skb(skb);
358 	return 0;
359 }
360 EXPORT_SYMBOL_GPL(fcoe_start_io);
361 
362 
363 /**
364  * fcoe_clean_pending_queue() - Dequeue a skb and free it
365  * @lport: The local port to dequeue a skb on
366  */
367 void fcoe_clean_pending_queue(struct fc_lport *lport)
368 {
369 	struct fcoe_port  *port = lport_priv(lport);
370 	struct sk_buff *skb;
371 
372 	spin_lock_bh(&port->fcoe_pending_queue.lock);
373 	while ((skb = __skb_dequeue(&port->fcoe_pending_queue)) != NULL) {
374 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
375 		kfree_skb(skb);
376 		spin_lock_bh(&port->fcoe_pending_queue.lock);
377 	}
378 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
379 }
380 EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue);
381 
382 /**
383  * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
384  * @lport: The local port whose backlog is to be cleared
385  *
386  * This empties the wait_queue, dequeues the head of the wait_queue queue
387  * and calls fcoe_start_io() for each packet. If all skb have been
388  * transmitted it returns the qlen. If an error occurs it restores
389  * wait_queue (to try again later) and returns -1.
390  *
391  * The wait_queue is used when the skb transmit fails. The failed skb
392  * will go in the wait_queue which will be emptied by the timer function or
393  * by the next skb transmit.
394  */
395 void fcoe_check_wait_queue(struct fc_lport *lport, struct sk_buff *skb)
396 {
397 	struct fcoe_port *port = lport_priv(lport);
398 	int rc;
399 
400 	spin_lock_bh(&port->fcoe_pending_queue.lock);
401 
402 	if (skb)
403 		__skb_queue_tail(&port->fcoe_pending_queue, skb);
404 
405 	if (port->fcoe_pending_queue_active)
406 		goto out;
407 	port->fcoe_pending_queue_active = 1;
408 
409 	while (port->fcoe_pending_queue.qlen) {
410 		/* keep qlen > 0 until fcoe_start_io succeeds */
411 		port->fcoe_pending_queue.qlen++;
412 		skb = __skb_dequeue(&port->fcoe_pending_queue);
413 
414 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
415 		rc = fcoe_start_io(skb);
416 		spin_lock_bh(&port->fcoe_pending_queue.lock);
417 
418 		if (rc) {
419 			__skb_queue_head(&port->fcoe_pending_queue, skb);
420 			/* undo temporary increment above */
421 			port->fcoe_pending_queue.qlen--;
422 			break;
423 		}
424 		/* undo temporary increment above */
425 		port->fcoe_pending_queue.qlen--;
426 	}
427 
428 	if (port->fcoe_pending_queue.qlen < port->min_queue_depth)
429 		lport->qfull = 0;
430 	if (port->fcoe_pending_queue.qlen && !timer_pending(&port->timer))
431 		mod_timer(&port->timer, jiffies + 2);
432 	port->fcoe_pending_queue_active = 0;
433 out:
434 	if (port->fcoe_pending_queue.qlen > port->max_queue_depth)
435 		lport->qfull = 1;
436 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
437 }
438 EXPORT_SYMBOL_GPL(fcoe_check_wait_queue);
439 
440 /**
441  * fcoe_queue_timer() - The fcoe queue timer
442  * @lport: The local port
443  *
444  * Calls fcoe_check_wait_queue on timeout
445  */
446 void fcoe_queue_timer(struct timer_list *t)
447 {
448 	struct fcoe_port *port = from_timer(port, t, timer);
449 
450 	fcoe_check_wait_queue(port->lport, NULL);
451 }
452 EXPORT_SYMBOL_GPL(fcoe_queue_timer);
453 
454 /**
455  * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
456  * @skb:  The packet to be transmitted
457  * @tlen: The total length of the trailer
458  * @fps:  The fcoe context
459  *
460  * This routine allocates a page for frame trailers. The page is re-used if
461  * there is enough room left on it for the current trailer. If there isn't
462  * enough buffer left a new page is allocated for the trailer. Reference to
463  * the page from this function as well as the skbs using the page fragments
464  * ensure that the page is freed at the appropriate time.
465  *
466  * Returns: 0 for success
467  */
468 int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen,
469 			   struct fcoe_percpu_s *fps)
470 {
471 	struct page *page;
472 
473 	page = fps->crc_eof_page;
474 	if (!page) {
475 		page = alloc_page(GFP_ATOMIC);
476 		if (!page)
477 			return -ENOMEM;
478 
479 		fps->crc_eof_page = page;
480 		fps->crc_eof_offset = 0;
481 	}
482 
483 	get_page(page);
484 	skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page,
485 			   fps->crc_eof_offset, tlen);
486 	skb->len += tlen;
487 	skb->data_len += tlen;
488 	skb->truesize += tlen;
489 	fps->crc_eof_offset += sizeof(struct fcoe_crc_eof);
490 
491 	if (fps->crc_eof_offset >= PAGE_SIZE) {
492 		fps->crc_eof_page = NULL;
493 		fps->crc_eof_offset = 0;
494 		put_page(page);
495 	}
496 
497 	return 0;
498 }
499 EXPORT_SYMBOL_GPL(fcoe_get_paged_crc_eof);
500 
501 /**
502  * fcoe_transport_lookup - find an fcoe transport that matches a netdev
503  * @netdev: The netdev to look for from all attached transports
504  *
505  * Returns : ptr to the fcoe transport that supports this netdev or NULL
506  * if not found.
507  *
508  * The ft_mutex should be held when this is called
509  */
510 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *netdev)
511 {
512 	struct fcoe_transport *ft = NULL;
513 
514 	list_for_each_entry(ft, &fcoe_transports, list)
515 		if (ft->match && ft->match(netdev))
516 			return ft;
517 	return NULL;
518 }
519 
520 /**
521  * fcoe_transport_attach - Attaches an FCoE transport
522  * @ft: The fcoe transport to be attached
523  *
524  * Returns : 0 for success
525  */
526 int fcoe_transport_attach(struct fcoe_transport *ft)
527 {
528 	int rc = 0;
529 
530 	mutex_lock(&ft_mutex);
531 	if (ft->attached) {
532 		LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
533 				       ft->name);
534 		rc = -EEXIST;
535 		goto out_attach;
536 	}
537 
538 	/* Add default transport to the tail */
539 	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
540 		list_add(&ft->list, &fcoe_transports);
541 	else
542 		list_add_tail(&ft->list, &fcoe_transports);
543 
544 	ft->attached = true;
545 	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);
546 
547 out_attach:
548 	mutex_unlock(&ft_mutex);
549 	return rc;
550 }
551 EXPORT_SYMBOL(fcoe_transport_attach);
552 
553 /**
554  * fcoe_transport_detach - Detaches an FCoE transport
555  * @ft: The fcoe transport to be attached
556  *
557  * Returns : 0 for success
558  */
559 int fcoe_transport_detach(struct fcoe_transport *ft)
560 {
561 	int rc = 0;
562 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
563 
564 	mutex_lock(&ft_mutex);
565 	if (!ft->attached) {
566 		LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
567 			ft->name);
568 		rc = -ENODEV;
569 		goto out_attach;
570 	}
571 
572 	/* remove netdev mapping for this transport as it is going away */
573 	mutex_lock(&fn_mutex);
574 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
575 		if (nm->ft == ft) {
576 			LIBFCOE_TRANSPORT_DBG("transport %s going away, "
577 				"remove its netdev mapping for %s\n",
578 				ft->name, nm->netdev->name);
579 			list_del(&nm->list);
580 			kfree(nm);
581 		}
582 	}
583 	mutex_unlock(&fn_mutex);
584 
585 	list_del(&ft->list);
586 	ft->attached = false;
587 	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);
588 
589 out_attach:
590 	mutex_unlock(&ft_mutex);
591 	return rc;
592 
593 }
594 EXPORT_SYMBOL(fcoe_transport_detach);
595 
596 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp)
597 {
598 	int i, j;
599 	struct fcoe_transport *ft = NULL;
600 
601 	i = j = sprintf(buffer, "Attached FCoE transports:");
602 	mutex_lock(&ft_mutex);
603 	list_for_each_entry(ft, &fcoe_transports, list) {
604 		if (i >= PAGE_SIZE - IFNAMSIZ)
605 			break;
606 		i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
607 	}
608 	mutex_unlock(&ft_mutex);
609 	if (i == j)
610 		i += snprintf(&buffer[i], IFNAMSIZ, "none");
611 	return i;
612 }
613 
614 static int __init fcoe_transport_init(void)
615 {
616 	register_netdevice_notifier(&libfcoe_notifier);
617 	return 0;
618 }
619 
620 static int fcoe_transport_exit(void)
621 {
622 	struct fcoe_transport *ft;
623 
624 	unregister_netdevice_notifier(&libfcoe_notifier);
625 	mutex_lock(&ft_mutex);
626 	list_for_each_entry(ft, &fcoe_transports, list)
627 		printk(KERN_ERR "FCoE transport %s is still attached!\n",
628 		      ft->name);
629 	mutex_unlock(&ft_mutex);
630 	return 0;
631 }
632 
633 
634 static int fcoe_add_netdev_mapping(struct net_device *netdev,
635 					struct fcoe_transport *ft)
636 {
637 	struct fcoe_netdev_mapping *nm;
638 
639 	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
640 	if (!nm) {
641 		printk(KERN_ERR "Unable to allocate netdev_mapping");
642 		return -ENOMEM;
643 	}
644 
645 	nm->netdev = netdev;
646 	nm->ft = ft;
647 
648 	mutex_lock(&fn_mutex);
649 	list_add(&nm->list, &fcoe_netdevs);
650 	mutex_unlock(&fn_mutex);
651 	return 0;
652 }
653 
654 
655 static void fcoe_del_netdev_mapping(struct net_device *netdev)
656 {
657 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
658 
659 	mutex_lock(&fn_mutex);
660 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
661 		if (nm->netdev == netdev) {
662 			list_del(&nm->list);
663 			kfree(nm);
664 			mutex_unlock(&fn_mutex);
665 			return;
666 		}
667 	}
668 	mutex_unlock(&fn_mutex);
669 }
670 
671 
672 /**
673  * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
674  * it was created
675  *
676  * Returns : ptr to the fcoe transport that supports this netdev or NULL
677  * if not found.
678  *
679  * The ft_mutex should be held when this is called
680  */
681 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *netdev)
682 {
683 	struct fcoe_transport *ft = NULL;
684 	struct fcoe_netdev_mapping *nm;
685 
686 	mutex_lock(&fn_mutex);
687 	list_for_each_entry(nm, &fcoe_netdevs, list) {
688 		if (netdev == nm->netdev) {
689 			ft = nm->ft;
690 			mutex_unlock(&fn_mutex);
691 			return ft;
692 		}
693 	}
694 
695 	mutex_unlock(&fn_mutex);
696 	return NULL;
697 }
698 
699 /**
700  * fcoe_if_to_netdev() - Parse a name buffer to get a net device
701  * @buffer: The name of the net device
702  *
703  * Returns: NULL or a ptr to net_device
704  */
705 static struct net_device *fcoe_if_to_netdev(const char *buffer)
706 {
707 	char *cp;
708 	char ifname[IFNAMSIZ + 2];
709 
710 	if (buffer) {
711 		strlcpy(ifname, buffer, IFNAMSIZ);
712 		cp = ifname + strlen(ifname);
713 		while (--cp >= ifname && *cp == '\n')
714 			*cp = '\0';
715 		return dev_get_by_name(&init_net, ifname);
716 	}
717 	return NULL;
718 }
719 
720 /**
721  * libfcoe_device_notification() - Handler for net device events
722  * @notifier: The context of the notification
723  * @event:    The type of event
724  * @ptr:      The net device that the event was on
725  *
726  * This function is called by the Ethernet driver in case of link change event.
727  *
728  * Returns: 0 for success
729  */
730 static int libfcoe_device_notification(struct notifier_block *notifier,
731 				    ulong event, void *ptr)
732 {
733 	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
734 
735 	switch (event) {
736 	case NETDEV_UNREGISTER:
737 		LIBFCOE_TRANSPORT_DBG("NETDEV_UNREGISTER %s\n",
738 				      netdev->name);
739 		fcoe_del_netdev_mapping(netdev);
740 		break;
741 	}
742 	return NOTIFY_OK;
743 }
744 
745 ssize_t fcoe_ctlr_create_store(struct bus_type *bus,
746 			       const char *buf, size_t count)
747 {
748 	struct net_device *netdev = NULL;
749 	struct fcoe_transport *ft = NULL;
750 	int rc = 0;
751 	int err;
752 
753 	mutex_lock(&ft_mutex);
754 
755 	netdev = fcoe_if_to_netdev(buf);
756 	if (!netdev) {
757 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buf);
758 		rc = -ENODEV;
759 		goto out_nodev;
760 	}
761 
762 	ft = fcoe_netdev_map_lookup(netdev);
763 	if (ft) {
764 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
765 				      "FCoE instance on %s.\n",
766 				      ft->name, netdev->name);
767 		rc = -EEXIST;
768 		goto out_putdev;
769 	}
770 
771 	ft = fcoe_transport_lookup(netdev);
772 	if (!ft) {
773 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
774 				      netdev->name);
775 		rc = -ENODEV;
776 		goto out_putdev;
777 	}
778 
779 	/* pass to transport create */
780 	err = ft->alloc ? ft->alloc(netdev) : -ENODEV;
781 	if (err) {
782 		fcoe_del_netdev_mapping(netdev);
783 		rc = -ENOMEM;
784 		goto out_putdev;
785 	}
786 
787 	err = fcoe_add_netdev_mapping(netdev, ft);
788 	if (err) {
789 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
790 				      "for FCoE transport %s for %s.\n",
791 				      ft->name, netdev->name);
792 		rc = -ENODEV;
793 		goto out_putdev;
794 	}
795 
796 	LIBFCOE_TRANSPORT_DBG("transport %s succeeded to create fcoe on %s.\n",
797 			      ft->name, netdev->name);
798 
799 out_putdev:
800 	dev_put(netdev);
801 out_nodev:
802 	mutex_unlock(&ft_mutex);
803 	if (rc)
804 		return rc;
805 	return count;
806 }
807 
808 ssize_t fcoe_ctlr_destroy_store(struct bus_type *bus,
809 				const char *buf, size_t count)
810 {
811 	int rc = -ENODEV;
812 	struct net_device *netdev = NULL;
813 	struct fcoe_transport *ft = NULL;
814 
815 	mutex_lock(&ft_mutex);
816 
817 	netdev = fcoe_if_to_netdev(buf);
818 	if (!netdev) {
819 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buf);
820 		goto out_nodev;
821 	}
822 
823 	ft = fcoe_netdev_map_lookup(netdev);
824 	if (!ft) {
825 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
826 				      netdev->name);
827 		goto out_putdev;
828 	}
829 
830 	/* pass to transport destroy */
831 	rc = ft->destroy(netdev);
832 	if (rc)
833 		goto out_putdev;
834 
835 	fcoe_del_netdev_mapping(netdev);
836 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
837 			      ft->name, (rc) ? "failed" : "succeeded",
838 			      netdev->name);
839 	rc = count; /* required for successful return */
840 out_putdev:
841 	dev_put(netdev);
842 out_nodev:
843 	mutex_unlock(&ft_mutex);
844 	return rc;
845 }
846 
847 /**
848  * fcoe_transport_create() - Create a fcoe interface
849  * @buffer: The name of the Ethernet interface to create on
850  * @kp:	    The associated kernel param
851  *
852  * Called from sysfs. This holds the ft_mutex while calling the
853  * registered fcoe transport's create function.
854  *
855  * Returns: 0 for success
856  */
857 static int fcoe_transport_create(const char *buffer,
858 				 const struct kernel_param *kp)
859 {
860 	int rc = -ENODEV;
861 	struct net_device *netdev = NULL;
862 	struct fcoe_transport *ft = NULL;
863 	enum fip_mode fip_mode = (enum fip_mode)kp->arg;
864 
865 	mutex_lock(&ft_mutex);
866 
867 	netdev = fcoe_if_to_netdev(buffer);
868 	if (!netdev) {
869 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
870 		goto out_nodev;
871 	}
872 
873 	ft = fcoe_netdev_map_lookup(netdev);
874 	if (ft) {
875 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
876 				      "FCoE instance on %s.\n",
877 				      ft->name, netdev->name);
878 		rc = -EEXIST;
879 		goto out_putdev;
880 	}
881 
882 	ft = fcoe_transport_lookup(netdev);
883 	if (!ft) {
884 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
885 				      netdev->name);
886 		goto out_putdev;
887 	}
888 
889 	rc = fcoe_add_netdev_mapping(netdev, ft);
890 	if (rc) {
891 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
892 				      "for FCoE transport %s for %s.\n",
893 				      ft->name, netdev->name);
894 		goto out_putdev;
895 	}
896 
897 	/* pass to transport create */
898 	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
899 	if (rc)
900 		fcoe_del_netdev_mapping(netdev);
901 
902 	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
903 			      ft->name, (rc) ? "failed" : "succeeded",
904 			      netdev->name);
905 
906 out_putdev:
907 	dev_put(netdev);
908 out_nodev:
909 	mutex_unlock(&ft_mutex);
910 	return rc;
911 }
912 
913 /**
914  * fcoe_transport_destroy() - Destroy a FCoE interface
915  * @buffer: The name of the Ethernet interface to be destroyed
916  * @kp:	    The associated kernel parameter
917  *
918  * Called from sysfs. This holds the ft_mutex while calling the
919  * registered fcoe transport's destroy function.
920  *
921  * Returns: 0 for success
922  */
923 static int fcoe_transport_destroy(const char *buffer,
924 				  const struct kernel_param *kp)
925 {
926 	int rc = -ENODEV;
927 	struct net_device *netdev = NULL;
928 	struct fcoe_transport *ft = NULL;
929 
930 	mutex_lock(&ft_mutex);
931 
932 	netdev = fcoe_if_to_netdev(buffer);
933 	if (!netdev) {
934 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
935 		goto out_nodev;
936 	}
937 
938 	ft = fcoe_netdev_map_lookup(netdev);
939 	if (!ft) {
940 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
941 				      netdev->name);
942 		goto out_putdev;
943 	}
944 
945 	/* pass to transport destroy */
946 	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
947 	fcoe_del_netdev_mapping(netdev);
948 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
949 			      ft->name, (rc) ? "failed" : "succeeded",
950 			      netdev->name);
951 
952 out_putdev:
953 	dev_put(netdev);
954 out_nodev:
955 	mutex_unlock(&ft_mutex);
956 	return rc;
957 }
958 
959 /**
960  * fcoe_transport_disable() - Disables a FCoE interface
961  * @buffer: The name of the Ethernet interface to be disabled
962  * @kp:	    The associated kernel parameter
963  *
964  * Called from sysfs.
965  *
966  * Returns: 0 for success
967  */
968 static int fcoe_transport_disable(const char *buffer,
969 				  const struct kernel_param *kp)
970 {
971 	int rc = -ENODEV;
972 	struct net_device *netdev = NULL;
973 	struct fcoe_transport *ft = NULL;
974 
975 	mutex_lock(&ft_mutex);
976 
977 	netdev = fcoe_if_to_netdev(buffer);
978 	if (!netdev)
979 		goto out_nodev;
980 
981 	ft = fcoe_netdev_map_lookup(netdev);
982 	if (!ft)
983 		goto out_putdev;
984 
985 	rc = ft->disable ? ft->disable(netdev) : -ENODEV;
986 
987 out_putdev:
988 	dev_put(netdev);
989 out_nodev:
990 	mutex_unlock(&ft_mutex);
991 	return rc;
992 }
993 
994 /**
995  * fcoe_transport_enable() - Enables a FCoE interface
996  * @buffer: The name of the Ethernet interface to be enabled
997  * @kp:     The associated kernel parameter
998  *
999  * Called from sysfs.
1000  *
1001  * Returns: 0 for success
1002  */
1003 static int fcoe_transport_enable(const char *buffer,
1004 				 const struct kernel_param *kp)
1005 {
1006 	int rc = -ENODEV;
1007 	struct net_device *netdev = NULL;
1008 	struct fcoe_transport *ft = NULL;
1009 
1010 	mutex_lock(&ft_mutex);
1011 
1012 	netdev = fcoe_if_to_netdev(buffer);
1013 	if (!netdev)
1014 		goto out_nodev;
1015 
1016 	ft = fcoe_netdev_map_lookup(netdev);
1017 	if (!ft)
1018 		goto out_putdev;
1019 
1020 	rc = ft->enable ? ft->enable(netdev) : -ENODEV;
1021 
1022 out_putdev:
1023 	dev_put(netdev);
1024 out_nodev:
1025 	mutex_unlock(&ft_mutex);
1026 	return rc;
1027 }
1028 
1029 /**
1030  * libfcoe_init() - Initialization routine for libfcoe.ko
1031  */
1032 static int __init libfcoe_init(void)
1033 {
1034 	int rc = 0;
1035 
1036 	rc = fcoe_transport_init();
1037 	if (rc)
1038 		return rc;
1039 
1040 	rc = fcoe_sysfs_setup();
1041 	if (rc)
1042 		fcoe_transport_exit();
1043 
1044 	return rc;
1045 }
1046 module_init(libfcoe_init);
1047 
1048 /**
1049  * libfcoe_exit() - Tear down libfcoe.ko
1050  */
1051 static void __exit libfcoe_exit(void)
1052 {
1053 	fcoe_sysfs_teardown();
1054 	fcoe_transport_exit();
1055 }
1056 module_exit(libfcoe_exit);
1057