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 *, const struct kernel_param *);
36 static int fcoe_transport_destroy(const char *, const 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 *, const struct kernel_param *);
41 static int fcoe_transport_disable(const char *, const 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 an 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 an 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 an 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 an 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 
86 static const struct {
87 	u32 fc_port_speed;
88 #define SPEED_2000	2000
89 #define SPEED_4000	4000
90 #define SPEED_8000	8000
91 #define SPEED_16000	16000
92 #define SPEED_32000	32000
93 	u32 eth_port_speed;
94 } fcoe_port_speed_mapping[] = {
95 	{ FC_PORTSPEED_1GBIT,   SPEED_1000   },
96 	{ FC_PORTSPEED_2GBIT,   SPEED_2000   },
97 	{ FC_PORTSPEED_4GBIT,   SPEED_4000   },
98 	{ FC_PORTSPEED_8GBIT,   SPEED_8000   },
99 	{ FC_PORTSPEED_10GBIT,  SPEED_10000  },
100 	{ FC_PORTSPEED_16GBIT,  SPEED_16000  },
101 	{ FC_PORTSPEED_20GBIT,  SPEED_20000  },
102 	{ FC_PORTSPEED_25GBIT,  SPEED_25000  },
103 	{ FC_PORTSPEED_32GBIT,  SPEED_32000  },
104 	{ FC_PORTSPEED_40GBIT,  SPEED_40000  },
105 	{ FC_PORTSPEED_50GBIT,  SPEED_50000  },
106 	{ FC_PORTSPEED_100GBIT, SPEED_100000 },
107 };
108 
109 static inline u32 eth2fc_speed(u32 eth_port_speed)
110 {
111 	int i;
112 
113 	for (i = 0; i < ARRAY_SIZE(fcoe_port_speed_mapping); i++) {
114 		if (fcoe_port_speed_mapping[i].eth_port_speed == eth_port_speed)
115 			return fcoe_port_speed_mapping[i].fc_port_speed;
116 	}
117 
118 	return FC_PORTSPEED_UNKNOWN;
119 }
120 
121 /**
122  * fcoe_link_speed_update() - Update the supported and actual link speeds
123  * @lport: The local port to update speeds for
124  *
125  * Returns: 0 if the ethtool query was successful
126  *          -1 if the ethtool query failed
127  */
128 int fcoe_link_speed_update(struct fc_lport *lport)
129 {
130 	struct net_device *netdev = fcoe_get_netdev(lport);
131 	struct ethtool_link_ksettings ecmd;
132 
133 	if (!__ethtool_get_link_ksettings(netdev, &ecmd)) {
134 		lport->link_supported_speeds &= ~(FC_PORTSPEED_1GBIT  |
135 		                                  FC_PORTSPEED_10GBIT |
136 		                                  FC_PORTSPEED_20GBIT |
137 		                                  FC_PORTSPEED_40GBIT);
138 
139 		if (ecmd.link_modes.supported[0] & (
140 			    SUPPORTED_1000baseT_Half |
141 			    SUPPORTED_1000baseT_Full |
142 			    SUPPORTED_1000baseKX_Full))
143 			lport->link_supported_speeds |= FC_PORTSPEED_1GBIT;
144 
145 		if (ecmd.link_modes.supported[0] & (
146 			    SUPPORTED_10000baseT_Full   |
147 			    SUPPORTED_10000baseKX4_Full |
148 			    SUPPORTED_10000baseKR_Full  |
149 			    SUPPORTED_10000baseR_FEC))
150 			lport->link_supported_speeds |= FC_PORTSPEED_10GBIT;
151 
152 		if (ecmd.link_modes.supported[0] & (
153 			    SUPPORTED_20000baseMLD2_Full |
154 			    SUPPORTED_20000baseKR2_Full))
155 			lport->link_supported_speeds |= FC_PORTSPEED_20GBIT;
156 
157 		if (ecmd.link_modes.supported[0] & (
158 			    SUPPORTED_40000baseKR4_Full |
159 			    SUPPORTED_40000baseCR4_Full |
160 			    SUPPORTED_40000baseSR4_Full |
161 			    SUPPORTED_40000baseLR4_Full))
162 			lport->link_supported_speeds |= FC_PORTSPEED_40GBIT;
163 
164 		lport->link_speed = eth2fc_speed(ecmd.base.speed);
165 		return 0;
166 	}
167 	return -1;
168 }
169 EXPORT_SYMBOL_GPL(fcoe_link_speed_update);
170 
171 /**
172  * __fcoe_get_lesb() - Get the Link Error Status Block (LESB) for a given lport
173  * @lport: The local port to update speeds for
174  * @fc_lesb: Pointer to the LESB to be filled up
175  * @netdev: Pointer to the netdev that is associated with the lport
176  *
177  * Note, the Link Error Status Block (LESB) for FCoE is defined in FC-BB-6
178  * Clause 7.11 in v1.04.
179  */
180 void __fcoe_get_lesb(struct fc_lport *lport,
181 		     struct fc_els_lesb *fc_lesb,
182 		     struct net_device *netdev)
183 {
184 	unsigned int cpu;
185 	u32 lfc, vlfc, mdac;
186 	struct fc_stats *stats;
187 	struct fcoe_fc_els_lesb *lesb;
188 	struct rtnl_link_stats64 temp;
189 
190 	lfc = 0;
191 	vlfc = 0;
192 	mdac = 0;
193 	lesb = (struct fcoe_fc_els_lesb *)fc_lesb;
194 	memset(lesb, 0, sizeof(*lesb));
195 	for_each_possible_cpu(cpu) {
196 		stats = per_cpu_ptr(lport->stats, cpu);
197 		lfc += stats->LinkFailureCount;
198 		vlfc += stats->VLinkFailureCount;
199 		mdac += stats->MissDiscAdvCount;
200 	}
201 	lesb->lesb_link_fail = htonl(lfc);
202 	lesb->lesb_vlink_fail = htonl(vlfc);
203 	lesb->lesb_miss_fka = htonl(mdac);
204 	lesb->lesb_fcs_error =
205 			htonl(dev_get_stats(netdev, &temp)->rx_crc_errors);
206 }
207 EXPORT_SYMBOL_GPL(__fcoe_get_lesb);
208 
209 /**
210  * fcoe_get_lesb() - Fill the FCoE Link Error Status Block
211  * @lport: the local port
212  * @fc_lesb: the link error status block
213  */
214 void fcoe_get_lesb(struct fc_lport *lport,
215 			 struct fc_els_lesb *fc_lesb)
216 {
217 	struct net_device *netdev = fcoe_get_netdev(lport);
218 
219 	__fcoe_get_lesb(lport, fc_lesb, netdev);
220 }
221 EXPORT_SYMBOL_GPL(fcoe_get_lesb);
222 
223 /**
224  * fcoe_ctlr_get_lesb() - Get the Link Error Status Block (LESB) for a given
225  * fcoe controller device
226  * @ctlr_dev: The given fcoe controller device
227  *
228  */
229 void fcoe_ctlr_get_lesb(struct fcoe_ctlr_device *ctlr_dev)
230 {
231 	struct fcoe_ctlr *fip = fcoe_ctlr_device_priv(ctlr_dev);
232 	struct net_device *netdev = fcoe_get_netdev(fip->lp);
233 	struct fc_els_lesb *fc_lesb;
234 
235 	fc_lesb = (struct fc_els_lesb *)(&ctlr_dev->lesb);
236 	__fcoe_get_lesb(fip->lp, fc_lesb, netdev);
237 }
238 EXPORT_SYMBOL_GPL(fcoe_ctlr_get_lesb);
239 
240 void fcoe_wwn_to_str(u64 wwn, char *buf, int len)
241 {
242 	u8 wwpn[8];
243 
244 	u64_to_wwn(wwn, wwpn);
245 	snprintf(buf, len, "%02x%02x%02x%02x%02x%02x%02x%02x",
246 		 wwpn[0], wwpn[1], wwpn[2], wwpn[3],
247 		 wwpn[4], wwpn[5], wwpn[6], wwpn[7]);
248 }
249 EXPORT_SYMBOL_GPL(fcoe_wwn_to_str);
250 
251 /**
252  * fcoe_validate_vport_create() - Validate a vport before creating it
253  * @vport: NPIV port to be created
254  *
255  * This routine is meant to add validation for a vport before creating it
256  * via fcoe_vport_create().
257  * Current validations are:
258  *      - WWPN supplied is unique for given lport
259  */
260 int fcoe_validate_vport_create(struct fc_vport *vport)
261 {
262 	struct Scsi_Host *shost = vport_to_shost(vport);
263 	struct fc_lport *n_port = shost_priv(shost);
264 	struct fc_lport *vn_port;
265 	int rc = 0;
266 	char buf[32];
267 
268 	mutex_lock(&n_port->lp_mutex);
269 
270 	fcoe_wwn_to_str(vport->port_name, buf, sizeof(buf));
271 	/* Check if the wwpn is not same as that of the lport */
272 	if (!memcmp(&n_port->wwpn, &vport->port_name, sizeof(u64))) {
273 		LIBFCOE_TRANSPORT_DBG("vport WWPN 0x%s is same as that of the "
274 				      "base port WWPN\n", buf);
275 		rc = -EINVAL;
276 		goto out;
277 	}
278 
279 	/* Check if there is any existing vport with same wwpn */
280 	list_for_each_entry(vn_port, &n_port->vports, list) {
281 		if (!memcmp(&vn_port->wwpn, &vport->port_name, sizeof(u64))) {
282 			LIBFCOE_TRANSPORT_DBG("vport with given WWPN 0x%s "
283 					      "already exists\n", buf);
284 			rc = -EINVAL;
285 			break;
286 		}
287 	}
288 out:
289 	mutex_unlock(&n_port->lp_mutex);
290 	return rc;
291 }
292 EXPORT_SYMBOL_GPL(fcoe_validate_vport_create);
293 
294 /**
295  * fcoe_get_wwn() - Get the world wide name from LLD if it supports it
296  * @netdev: the associated net device
297  * @wwn: the output WWN
298  * @type: the type of WWN (WWPN or WWNN)
299  *
300  * Returns: 0 for success
301  */
302 int fcoe_get_wwn(struct net_device *netdev, u64 *wwn, int type)
303 {
304 	const struct net_device_ops *ops = netdev->netdev_ops;
305 
306 	if (ops->ndo_fcoe_get_wwn)
307 		return ops->ndo_fcoe_get_wwn(netdev, wwn, type);
308 	return -EINVAL;
309 }
310 EXPORT_SYMBOL_GPL(fcoe_get_wwn);
311 
312 /**
313  * fcoe_fc_crc() - Calculates the CRC for a given frame
314  * @fp: The frame to be checksumed
315  *
316  * This uses crc32() routine to calculate the CRC for a frame
317  *
318  * Return: The 32 bit CRC value
319  */
320 u32 fcoe_fc_crc(struct fc_frame *fp)
321 {
322 	struct sk_buff *skb = fp_skb(fp);
323 	struct skb_frag_struct *frag;
324 	unsigned char *data;
325 	unsigned long off, len, clen;
326 	u32 crc;
327 	unsigned i;
328 
329 	crc = crc32(~0, skb->data, skb_headlen(skb));
330 
331 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
332 		frag = &skb_shinfo(skb)->frags[i];
333 		off = frag->page_offset;
334 		len = skb_frag_size(frag);
335 		while (len > 0) {
336 			clen = min(len, PAGE_SIZE - (off & ~PAGE_MASK));
337 			data = kmap_atomic(
338 				skb_frag_page(frag) + (off >> PAGE_SHIFT));
339 			crc = crc32(crc, data + (off & ~PAGE_MASK), clen);
340 			kunmap_atomic(data);
341 			off += clen;
342 			len -= clen;
343 		}
344 	}
345 	return crc;
346 }
347 EXPORT_SYMBOL_GPL(fcoe_fc_crc);
348 
349 /**
350  * fcoe_start_io() - Start FCoE I/O
351  * @skb: The packet to be transmitted
352  *
353  * This routine is called from the net device to start transmitting
354  * FCoE packets.
355  *
356  * Returns: 0 for success
357  */
358 int fcoe_start_io(struct sk_buff *skb)
359 {
360 	struct sk_buff *nskb;
361 	int rc;
362 
363 	nskb = skb_clone(skb, GFP_ATOMIC);
364 	if (!nskb)
365 		return -ENOMEM;
366 	rc = dev_queue_xmit(nskb);
367 	if (rc != 0)
368 		return rc;
369 	kfree_skb(skb);
370 	return 0;
371 }
372 EXPORT_SYMBOL_GPL(fcoe_start_io);
373 
374 
375 /**
376  * fcoe_clean_pending_queue() - Dequeue a skb and free it
377  * @lport: The local port to dequeue a skb on
378  */
379 void fcoe_clean_pending_queue(struct fc_lport *lport)
380 {
381 	struct fcoe_port  *port = lport_priv(lport);
382 	struct sk_buff *skb;
383 
384 	spin_lock_bh(&port->fcoe_pending_queue.lock);
385 	while ((skb = __skb_dequeue(&port->fcoe_pending_queue)) != NULL) {
386 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
387 		kfree_skb(skb);
388 		spin_lock_bh(&port->fcoe_pending_queue.lock);
389 	}
390 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
391 }
392 EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue);
393 
394 /**
395  * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
396  * @lport: The local port whose backlog is to be cleared
397  *
398  * This empties the wait_queue, dequeues the head of the wait_queue queue
399  * and calls fcoe_start_io() for each packet. If all skb have been
400  * transmitted it returns the qlen. If an error occurs it restores
401  * wait_queue (to try again later) and returns -1.
402  *
403  * The wait_queue is used when the skb transmit fails. The failed skb
404  * will go in the wait_queue which will be emptied by the timer function or
405  * by the next skb transmit.
406  */
407 void fcoe_check_wait_queue(struct fc_lport *lport, struct sk_buff *skb)
408 {
409 	struct fcoe_port *port = lport_priv(lport);
410 	int rc;
411 
412 	spin_lock_bh(&port->fcoe_pending_queue.lock);
413 
414 	if (skb)
415 		__skb_queue_tail(&port->fcoe_pending_queue, skb);
416 
417 	if (port->fcoe_pending_queue_active)
418 		goto out;
419 	port->fcoe_pending_queue_active = 1;
420 
421 	while (port->fcoe_pending_queue.qlen) {
422 		/* keep qlen > 0 until fcoe_start_io succeeds */
423 		port->fcoe_pending_queue.qlen++;
424 		skb = __skb_dequeue(&port->fcoe_pending_queue);
425 
426 		spin_unlock_bh(&port->fcoe_pending_queue.lock);
427 		rc = fcoe_start_io(skb);
428 		spin_lock_bh(&port->fcoe_pending_queue.lock);
429 
430 		if (rc) {
431 			__skb_queue_head(&port->fcoe_pending_queue, skb);
432 			/* undo temporary increment above */
433 			port->fcoe_pending_queue.qlen--;
434 			break;
435 		}
436 		/* undo temporary increment above */
437 		port->fcoe_pending_queue.qlen--;
438 	}
439 
440 	if (port->fcoe_pending_queue.qlen < port->min_queue_depth)
441 		lport->qfull = 0;
442 	if (port->fcoe_pending_queue.qlen && !timer_pending(&port->timer))
443 		mod_timer(&port->timer, jiffies + 2);
444 	port->fcoe_pending_queue_active = 0;
445 out:
446 	if (port->fcoe_pending_queue.qlen > port->max_queue_depth)
447 		lport->qfull = 1;
448 	spin_unlock_bh(&port->fcoe_pending_queue.lock);
449 }
450 EXPORT_SYMBOL_GPL(fcoe_check_wait_queue);
451 
452 /**
453  * fcoe_queue_timer() - The fcoe queue timer
454  * @lport: The local port
455  *
456  * Calls fcoe_check_wait_queue on timeout
457  */
458 void fcoe_queue_timer(struct timer_list *t)
459 {
460 	struct fcoe_port *port = from_timer(port, t, timer);
461 
462 	fcoe_check_wait_queue(port->lport, NULL);
463 }
464 EXPORT_SYMBOL_GPL(fcoe_queue_timer);
465 
466 /**
467  * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
468  * @skb:  The packet to be transmitted
469  * @tlen: The total length of the trailer
470  * @fps:  The fcoe context
471  *
472  * This routine allocates a page for frame trailers. The page is re-used if
473  * there is enough room left on it for the current trailer. If there isn't
474  * enough buffer left a new page is allocated for the trailer. Reference to
475  * the page from this function as well as the skbs using the page fragments
476  * ensure that the page is freed at the appropriate time.
477  *
478  * Returns: 0 for success
479  */
480 int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen,
481 			   struct fcoe_percpu_s *fps)
482 {
483 	struct page *page;
484 
485 	page = fps->crc_eof_page;
486 	if (!page) {
487 		page = alloc_page(GFP_ATOMIC);
488 		if (!page)
489 			return -ENOMEM;
490 
491 		fps->crc_eof_page = page;
492 		fps->crc_eof_offset = 0;
493 	}
494 
495 	get_page(page);
496 	skb_fill_page_desc(skb, skb_shinfo(skb)->nr_frags, page,
497 			   fps->crc_eof_offset, tlen);
498 	skb->len += tlen;
499 	skb->data_len += tlen;
500 	skb->truesize += tlen;
501 	fps->crc_eof_offset += sizeof(struct fcoe_crc_eof);
502 
503 	if (fps->crc_eof_offset >= PAGE_SIZE) {
504 		fps->crc_eof_page = NULL;
505 		fps->crc_eof_offset = 0;
506 		put_page(page);
507 	}
508 
509 	return 0;
510 }
511 EXPORT_SYMBOL_GPL(fcoe_get_paged_crc_eof);
512 
513 /**
514  * fcoe_transport_lookup - find an fcoe transport that matches a netdev
515  * @netdev: The netdev to look for from all attached transports
516  *
517  * Returns : ptr to the fcoe transport that supports this netdev or NULL
518  * if not found.
519  *
520  * The ft_mutex should be held when this is called
521  */
522 static struct fcoe_transport *fcoe_transport_lookup(struct net_device *netdev)
523 {
524 	struct fcoe_transport *ft = NULL;
525 
526 	list_for_each_entry(ft, &fcoe_transports, list)
527 		if (ft->match && ft->match(netdev))
528 			return ft;
529 	return NULL;
530 }
531 
532 /**
533  * fcoe_transport_attach - Attaches an FCoE transport
534  * @ft: The fcoe transport to be attached
535  *
536  * Returns : 0 for success
537  */
538 int fcoe_transport_attach(struct fcoe_transport *ft)
539 {
540 	int rc = 0;
541 
542 	mutex_lock(&ft_mutex);
543 	if (ft->attached) {
544 		LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
545 				       ft->name);
546 		rc = -EEXIST;
547 		goto out_attach;
548 	}
549 
550 	/* Add default transport to the tail */
551 	if (strcmp(ft->name, FCOE_TRANSPORT_DEFAULT))
552 		list_add(&ft->list, &fcoe_transports);
553 	else
554 		list_add_tail(&ft->list, &fcoe_transports);
555 
556 	ft->attached = true;
557 	LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft->name);
558 
559 out_attach:
560 	mutex_unlock(&ft_mutex);
561 	return rc;
562 }
563 EXPORT_SYMBOL(fcoe_transport_attach);
564 
565 /**
566  * fcoe_transport_detach - Detaches an FCoE transport
567  * @ft: The fcoe transport to be attached
568  *
569  * Returns : 0 for success
570  */
571 int fcoe_transport_detach(struct fcoe_transport *ft)
572 {
573 	int rc = 0;
574 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
575 
576 	mutex_lock(&ft_mutex);
577 	if (!ft->attached) {
578 		LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
579 			ft->name);
580 		rc = -ENODEV;
581 		goto out_attach;
582 	}
583 
584 	/* remove netdev mapping for this transport as it is going away */
585 	mutex_lock(&fn_mutex);
586 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
587 		if (nm->ft == ft) {
588 			LIBFCOE_TRANSPORT_DBG("transport %s going away, "
589 				"remove its netdev mapping for %s\n",
590 				ft->name, nm->netdev->name);
591 			list_del(&nm->list);
592 			kfree(nm);
593 		}
594 	}
595 	mutex_unlock(&fn_mutex);
596 
597 	list_del(&ft->list);
598 	ft->attached = false;
599 	LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft->name);
600 
601 out_attach:
602 	mutex_unlock(&ft_mutex);
603 	return rc;
604 
605 }
606 EXPORT_SYMBOL(fcoe_transport_detach);
607 
608 static int fcoe_transport_show(char *buffer, const struct kernel_param *kp)
609 {
610 	int i, j;
611 	struct fcoe_transport *ft = NULL;
612 
613 	i = j = sprintf(buffer, "Attached FCoE transports:");
614 	mutex_lock(&ft_mutex);
615 	list_for_each_entry(ft, &fcoe_transports, list) {
616 		if (i >= PAGE_SIZE - IFNAMSIZ)
617 			break;
618 		i += snprintf(&buffer[i], IFNAMSIZ, "%s ", ft->name);
619 	}
620 	mutex_unlock(&ft_mutex);
621 	if (i == j)
622 		i += snprintf(&buffer[i], IFNAMSIZ, "none");
623 	return i;
624 }
625 
626 static int __init fcoe_transport_init(void)
627 {
628 	register_netdevice_notifier(&libfcoe_notifier);
629 	return 0;
630 }
631 
632 static int fcoe_transport_exit(void)
633 {
634 	struct fcoe_transport *ft;
635 
636 	unregister_netdevice_notifier(&libfcoe_notifier);
637 	mutex_lock(&ft_mutex);
638 	list_for_each_entry(ft, &fcoe_transports, list)
639 		printk(KERN_ERR "FCoE transport %s is still attached!\n",
640 		      ft->name);
641 	mutex_unlock(&ft_mutex);
642 	return 0;
643 }
644 
645 
646 static int fcoe_add_netdev_mapping(struct net_device *netdev,
647 					struct fcoe_transport *ft)
648 {
649 	struct fcoe_netdev_mapping *nm;
650 
651 	nm = kmalloc(sizeof(*nm), GFP_KERNEL);
652 	if (!nm) {
653 		printk(KERN_ERR "Unable to allocate netdev_mapping");
654 		return -ENOMEM;
655 	}
656 
657 	nm->netdev = netdev;
658 	nm->ft = ft;
659 
660 	mutex_lock(&fn_mutex);
661 	list_add(&nm->list, &fcoe_netdevs);
662 	mutex_unlock(&fn_mutex);
663 	return 0;
664 }
665 
666 
667 static void fcoe_del_netdev_mapping(struct net_device *netdev)
668 {
669 	struct fcoe_netdev_mapping *nm = NULL, *tmp;
670 
671 	mutex_lock(&fn_mutex);
672 	list_for_each_entry_safe(nm, tmp, &fcoe_netdevs, list) {
673 		if (nm->netdev == netdev) {
674 			list_del(&nm->list);
675 			kfree(nm);
676 			mutex_unlock(&fn_mutex);
677 			return;
678 		}
679 	}
680 	mutex_unlock(&fn_mutex);
681 }
682 
683 
684 /**
685  * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
686  * it was created
687  *
688  * Returns : ptr to the fcoe transport that supports this netdev or NULL
689  * if not found.
690  *
691  * The ft_mutex should be held when this is called
692  */
693 static struct fcoe_transport *fcoe_netdev_map_lookup(struct net_device *netdev)
694 {
695 	struct fcoe_transport *ft = NULL;
696 	struct fcoe_netdev_mapping *nm;
697 
698 	mutex_lock(&fn_mutex);
699 	list_for_each_entry(nm, &fcoe_netdevs, list) {
700 		if (netdev == nm->netdev) {
701 			ft = nm->ft;
702 			mutex_unlock(&fn_mutex);
703 			return ft;
704 		}
705 	}
706 
707 	mutex_unlock(&fn_mutex);
708 	return NULL;
709 }
710 
711 /**
712  * fcoe_if_to_netdev() - Parse a name buffer to get a net device
713  * @buffer: The name of the net device
714  *
715  * Returns: NULL or a ptr to net_device
716  */
717 static struct net_device *fcoe_if_to_netdev(const char *buffer)
718 {
719 	char *cp;
720 	char ifname[IFNAMSIZ + 2];
721 
722 	if (buffer) {
723 		strlcpy(ifname, buffer, IFNAMSIZ);
724 		cp = ifname + strlen(ifname);
725 		while (--cp >= ifname && *cp == '\n')
726 			*cp = '\0';
727 		return dev_get_by_name(&init_net, ifname);
728 	}
729 	return NULL;
730 }
731 
732 /**
733  * libfcoe_device_notification() - Handler for net device events
734  * @notifier: The context of the notification
735  * @event:    The type of event
736  * @ptr:      The net device that the event was on
737  *
738  * This function is called by the Ethernet driver in case of link change event.
739  *
740  * Returns: 0 for success
741  */
742 static int libfcoe_device_notification(struct notifier_block *notifier,
743 				    ulong event, void *ptr)
744 {
745 	struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
746 
747 	switch (event) {
748 	case NETDEV_UNREGISTER:
749 		LIBFCOE_TRANSPORT_DBG("NETDEV_UNREGISTER %s\n",
750 				      netdev->name);
751 		fcoe_del_netdev_mapping(netdev);
752 		break;
753 	}
754 	return NOTIFY_OK;
755 }
756 
757 ssize_t fcoe_ctlr_create_store(struct bus_type *bus,
758 			       const char *buf, size_t count)
759 {
760 	struct net_device *netdev = NULL;
761 	struct fcoe_transport *ft = NULL;
762 	int rc = 0;
763 	int err;
764 
765 	mutex_lock(&ft_mutex);
766 
767 	netdev = fcoe_if_to_netdev(buf);
768 	if (!netdev) {
769 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buf);
770 		rc = -ENODEV;
771 		goto out_nodev;
772 	}
773 
774 	ft = fcoe_netdev_map_lookup(netdev);
775 	if (ft) {
776 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
777 				      "FCoE instance on %s.\n",
778 				      ft->name, netdev->name);
779 		rc = -EEXIST;
780 		goto out_putdev;
781 	}
782 
783 	ft = fcoe_transport_lookup(netdev);
784 	if (!ft) {
785 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
786 				      netdev->name);
787 		rc = -ENODEV;
788 		goto out_putdev;
789 	}
790 
791 	/* pass to transport create */
792 	err = ft->alloc ? ft->alloc(netdev) : -ENODEV;
793 	if (err) {
794 		fcoe_del_netdev_mapping(netdev);
795 		rc = -ENOMEM;
796 		goto out_putdev;
797 	}
798 
799 	err = fcoe_add_netdev_mapping(netdev, ft);
800 	if (err) {
801 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
802 				      "for FCoE transport %s for %s.\n",
803 				      ft->name, netdev->name);
804 		rc = -ENODEV;
805 		goto out_putdev;
806 	}
807 
808 	LIBFCOE_TRANSPORT_DBG("transport %s succeeded to create fcoe on %s.\n",
809 			      ft->name, netdev->name);
810 
811 out_putdev:
812 	dev_put(netdev);
813 out_nodev:
814 	mutex_unlock(&ft_mutex);
815 	if (rc)
816 		return rc;
817 	return count;
818 }
819 
820 ssize_t fcoe_ctlr_destroy_store(struct bus_type *bus,
821 				const char *buf, size_t count)
822 {
823 	int rc = -ENODEV;
824 	struct net_device *netdev = NULL;
825 	struct fcoe_transport *ft = NULL;
826 
827 	mutex_lock(&ft_mutex);
828 
829 	netdev = fcoe_if_to_netdev(buf);
830 	if (!netdev) {
831 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buf);
832 		goto out_nodev;
833 	}
834 
835 	ft = fcoe_netdev_map_lookup(netdev);
836 	if (!ft) {
837 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
838 				      netdev->name);
839 		goto out_putdev;
840 	}
841 
842 	/* pass to transport destroy */
843 	rc = ft->destroy(netdev);
844 	if (rc)
845 		goto out_putdev;
846 
847 	fcoe_del_netdev_mapping(netdev);
848 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
849 			      ft->name, (rc) ? "failed" : "succeeded",
850 			      netdev->name);
851 	rc = count; /* required for successful return */
852 out_putdev:
853 	dev_put(netdev);
854 out_nodev:
855 	mutex_unlock(&ft_mutex);
856 	return rc;
857 }
858 EXPORT_SYMBOL(fcoe_ctlr_destroy_store);
859 
860 /**
861  * fcoe_transport_create() - Create a fcoe interface
862  * @buffer: The name of the Ethernet interface to create on
863  * @kp:	    The associated kernel param
864  *
865  * Called from sysfs. This holds the ft_mutex while calling the
866  * registered fcoe transport's create function.
867  *
868  * Returns: 0 for success
869  */
870 static int fcoe_transport_create(const char *buffer,
871 				 const struct kernel_param *kp)
872 {
873 	int rc = -ENODEV;
874 	struct net_device *netdev = NULL;
875 	struct fcoe_transport *ft = NULL;
876 	enum fip_state fip_mode = (enum fip_state)(long)kp->arg;
877 
878 	mutex_lock(&ft_mutex);
879 
880 	netdev = fcoe_if_to_netdev(buffer);
881 	if (!netdev) {
882 		LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer);
883 		goto out_nodev;
884 	}
885 
886 	ft = fcoe_netdev_map_lookup(netdev);
887 	if (ft) {
888 		LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
889 				      "FCoE instance on %s.\n",
890 				      ft->name, netdev->name);
891 		rc = -EEXIST;
892 		goto out_putdev;
893 	}
894 
895 	ft = fcoe_transport_lookup(netdev);
896 	if (!ft) {
897 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
898 				      netdev->name);
899 		goto out_putdev;
900 	}
901 
902 	rc = fcoe_add_netdev_mapping(netdev, ft);
903 	if (rc) {
904 		LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
905 				      "for FCoE transport %s for %s.\n",
906 				      ft->name, netdev->name);
907 		goto out_putdev;
908 	}
909 
910 	/* pass to transport create */
911 	rc = ft->create ? ft->create(netdev, fip_mode) : -ENODEV;
912 	if (rc)
913 		fcoe_del_netdev_mapping(netdev);
914 
915 	LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
916 			      ft->name, (rc) ? "failed" : "succeeded",
917 			      netdev->name);
918 
919 out_putdev:
920 	dev_put(netdev);
921 out_nodev:
922 	mutex_unlock(&ft_mutex);
923 	return rc;
924 }
925 
926 /**
927  * fcoe_transport_destroy() - Destroy a FCoE interface
928  * @buffer: The name of the Ethernet interface to be destroyed
929  * @kp:	    The associated kernel parameter
930  *
931  * Called from sysfs. This holds the ft_mutex while calling the
932  * registered fcoe transport's destroy function.
933  *
934  * Returns: 0 for success
935  */
936 static int fcoe_transport_destroy(const char *buffer,
937 				  const struct kernel_param *kp)
938 {
939 	int rc = -ENODEV;
940 	struct net_device *netdev = NULL;
941 	struct fcoe_transport *ft = NULL;
942 
943 	mutex_lock(&ft_mutex);
944 
945 	netdev = fcoe_if_to_netdev(buffer);
946 	if (!netdev) {
947 		LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer);
948 		goto out_nodev;
949 	}
950 
951 	ft = fcoe_netdev_map_lookup(netdev);
952 	if (!ft) {
953 		LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
954 				      netdev->name);
955 		goto out_putdev;
956 	}
957 
958 	/* pass to transport destroy */
959 	rc = ft->destroy ? ft->destroy(netdev) : -ENODEV;
960 	fcoe_del_netdev_mapping(netdev);
961 	LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
962 			      ft->name, (rc) ? "failed" : "succeeded",
963 			      netdev->name);
964 
965 out_putdev:
966 	dev_put(netdev);
967 out_nodev:
968 	mutex_unlock(&ft_mutex);
969 	return rc;
970 }
971 
972 /**
973  * fcoe_transport_disable() - Disables a FCoE interface
974  * @buffer: The name of the Ethernet interface to be disabled
975  * @kp:	    The associated kernel parameter
976  *
977  * Called from sysfs.
978  *
979  * Returns: 0 for success
980  */
981 static int fcoe_transport_disable(const char *buffer,
982 				  const struct kernel_param *kp)
983 {
984 	int rc = -ENODEV;
985 	struct net_device *netdev = NULL;
986 	struct fcoe_transport *ft = NULL;
987 
988 	mutex_lock(&ft_mutex);
989 
990 	netdev = fcoe_if_to_netdev(buffer);
991 	if (!netdev)
992 		goto out_nodev;
993 
994 	ft = fcoe_netdev_map_lookup(netdev);
995 	if (!ft)
996 		goto out_putdev;
997 
998 	rc = ft->disable ? ft->disable(netdev) : -ENODEV;
999 
1000 out_putdev:
1001 	dev_put(netdev);
1002 out_nodev:
1003 	mutex_unlock(&ft_mutex);
1004 	return rc;
1005 }
1006 
1007 /**
1008  * fcoe_transport_enable() - Enables a FCoE interface
1009  * @buffer: The name of the Ethernet interface to be enabled
1010  * @kp:     The associated kernel parameter
1011  *
1012  * Called from sysfs.
1013  *
1014  * Returns: 0 for success
1015  */
1016 static int fcoe_transport_enable(const char *buffer,
1017 				 const struct kernel_param *kp)
1018 {
1019 	int rc = -ENODEV;
1020 	struct net_device *netdev = NULL;
1021 	struct fcoe_transport *ft = NULL;
1022 
1023 	mutex_lock(&ft_mutex);
1024 
1025 	netdev = fcoe_if_to_netdev(buffer);
1026 	if (!netdev)
1027 		goto out_nodev;
1028 
1029 	ft = fcoe_netdev_map_lookup(netdev);
1030 	if (!ft)
1031 		goto out_putdev;
1032 
1033 	rc = ft->enable ? ft->enable(netdev) : -ENODEV;
1034 
1035 out_putdev:
1036 	dev_put(netdev);
1037 out_nodev:
1038 	mutex_unlock(&ft_mutex);
1039 	return rc;
1040 }
1041 
1042 /**
1043  * libfcoe_init() - Initialization routine for libfcoe.ko
1044  */
1045 static int __init libfcoe_init(void)
1046 {
1047 	int rc = 0;
1048 
1049 	rc = fcoe_transport_init();
1050 	if (rc)
1051 		return rc;
1052 
1053 	rc = fcoe_sysfs_setup();
1054 	if (rc)
1055 		fcoe_transport_exit();
1056 
1057 	return rc;
1058 }
1059 module_init(libfcoe_init);
1060 
1061 /**
1062  * libfcoe_exit() - Tear down libfcoe.ko
1063  */
1064 static void __exit libfcoe_exit(void)
1065 {
1066 	fcoe_sysfs_teardown();
1067 	fcoe_transport_exit();
1068 }
1069 module_exit(libfcoe_exit);
1070