2 * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
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.
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
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.
17 * Maintained at www.Open-FCoE.org
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>
31 MODULE_AUTHOR("Open-FCoE.org");
32 MODULE_DESCRIPTION("FIP discovery protocol and FCoE transport for FCoE HBAs");
33 MODULE_LICENSE("GPL v2");
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
);
45 static LIST_HEAD(fcoe_transports
);
46 static DEFINE_MUTEX(ft_mutex
);
47 static LIST_HEAD(fcoe_netdevs
);
48 static DEFINE_MUTEX(fn_mutex
);
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");
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");
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");
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");
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");
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.");
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.");
81 /* notification function for packets from net device */
82 static struct notifier_block libfcoe_notifier
= {
83 .notifier_call
= libfcoe_device_notification
,
87 * fcoe_fc_crc() - Calculates the CRC for a given frame
88 * @fp: The frame to be checksumed
90 * This uses crc32() routine to calculate the CRC for a frame
92 * Return: The 32 bit CRC value
94 u32
fcoe_fc_crc(struct fc_frame
*fp
)
96 struct sk_buff
*skb
= fp_skb(fp
);
97 struct skb_frag_struct
*frag
;
99 unsigned long off
, len
, clen
;
103 crc
= crc32(~0, skb
->data
, skb_headlen(skb
));
105 for (i
= 0; i
< skb_shinfo(skb
)->nr_frags
; i
++) {
106 frag
= &skb_shinfo(skb
)->frags
[i
];
107 off
= frag
->page_offset
;
110 clen
= min(len
, PAGE_SIZE
- (off
& ~PAGE_MASK
));
111 data
= kmap_atomic(frag
->page
+ (off
>> PAGE_SHIFT
),
112 KM_SKB_DATA_SOFTIRQ
);
113 crc
= crc32(crc
, data
+ (off
& ~PAGE_MASK
), clen
);
114 kunmap_atomic(data
, KM_SKB_DATA_SOFTIRQ
);
121 EXPORT_SYMBOL_GPL(fcoe_fc_crc
);
124 * fcoe_start_io() - Start FCoE I/O
125 * @skb: The packet to be transmitted
127 * This routine is called from the net device to start transmitting
130 * Returns: 0 for success
132 int fcoe_start_io(struct sk_buff
*skb
)
134 struct sk_buff
*nskb
;
137 nskb
= skb_clone(skb
, GFP_ATOMIC
);
140 rc
= dev_queue_xmit(nskb
);
146 EXPORT_SYMBOL_GPL(fcoe_start_io
);
150 * fcoe_clean_pending_queue() - Dequeue a skb and free it
151 * @lport: The local port to dequeue a skb on
153 void fcoe_clean_pending_queue(struct fc_lport
*lport
)
155 struct fcoe_port
*port
= lport_priv(lport
);
158 spin_lock_bh(&port
->fcoe_pending_queue
.lock
);
159 while ((skb
= __skb_dequeue(&port
->fcoe_pending_queue
)) != NULL
) {
160 spin_unlock_bh(&port
->fcoe_pending_queue
.lock
);
162 spin_lock_bh(&port
->fcoe_pending_queue
.lock
);
164 spin_unlock_bh(&port
->fcoe_pending_queue
.lock
);
166 EXPORT_SYMBOL_GPL(fcoe_clean_pending_queue
);
169 * fcoe_check_wait_queue() - Attempt to clear the transmit backlog
170 * @lport: The local port whose backlog is to be cleared
172 * This empties the wait_queue, dequeues the head of the wait_queue queue
173 * and calls fcoe_start_io() for each packet. If all skb have been
174 * transmitted it returns the qlen. If an error occurs it restores
175 * wait_queue (to try again later) and returns -1.
177 * The wait_queue is used when the skb transmit fails. The failed skb
178 * will go in the wait_queue which will be emptied by the timer function or
179 * by the next skb transmit.
181 void fcoe_check_wait_queue(struct fc_lport
*lport
, struct sk_buff
*skb
)
183 struct fcoe_port
*port
= lport_priv(lport
);
186 spin_lock_bh(&port
->fcoe_pending_queue
.lock
);
189 __skb_queue_tail(&port
->fcoe_pending_queue
, skb
);
191 if (port
->fcoe_pending_queue_active
)
193 port
->fcoe_pending_queue_active
= 1;
195 while (port
->fcoe_pending_queue
.qlen
) {
196 /* keep qlen > 0 until fcoe_start_io succeeds */
197 port
->fcoe_pending_queue
.qlen
++;
198 skb
= __skb_dequeue(&port
->fcoe_pending_queue
);
200 spin_unlock_bh(&port
->fcoe_pending_queue
.lock
);
201 rc
= fcoe_start_io(skb
);
202 spin_lock_bh(&port
->fcoe_pending_queue
.lock
);
205 __skb_queue_head(&port
->fcoe_pending_queue
, skb
);
206 /* undo temporary increment above */
207 port
->fcoe_pending_queue
.qlen
--;
210 /* undo temporary increment above */
211 port
->fcoe_pending_queue
.qlen
--;
214 if (port
->fcoe_pending_queue
.qlen
< port
->min_queue_depth
)
216 if (port
->fcoe_pending_queue
.qlen
&& !timer_pending(&port
->timer
))
217 mod_timer(&port
->timer
, jiffies
+ 2);
218 port
->fcoe_pending_queue_active
= 0;
220 if (port
->fcoe_pending_queue
.qlen
> port
->max_queue_depth
)
222 spin_unlock_bh(&port
->fcoe_pending_queue
.lock
);
224 EXPORT_SYMBOL_GPL(fcoe_check_wait_queue
);
227 * fcoe_queue_timer() - The fcoe queue timer
228 * @lport: The local port
230 * Calls fcoe_check_wait_queue on timeout
232 void fcoe_queue_timer(ulong lport
)
234 fcoe_check_wait_queue((struct fc_lport
*)lport
, NULL
);
236 EXPORT_SYMBOL_GPL(fcoe_queue_timer
);
239 * fcoe_get_paged_crc_eof() - Allocate a page to be used for the trailer CRC
240 * @skb: The packet to be transmitted
241 * @tlen: The total length of the trailer
242 * @fps: The fcoe context
244 * This routine allocates a page for frame trailers. The page is re-used if
245 * there is enough room left on it for the current trailer. If there isn't
246 * enough buffer left a new page is allocated for the trailer. Reference to
247 * the page from this function as well as the skbs using the page fragments
248 * ensure that the page is freed at the appropriate time.
250 * Returns: 0 for success
252 int fcoe_get_paged_crc_eof(struct sk_buff
*skb
, int tlen
,
253 struct fcoe_percpu_s
*fps
)
257 page
= fps
->crc_eof_page
;
259 page
= alloc_page(GFP_ATOMIC
);
263 fps
->crc_eof_page
= page
;
264 fps
->crc_eof_offset
= 0;
268 skb_fill_page_desc(skb
, skb_shinfo(skb
)->nr_frags
, page
,
269 fps
->crc_eof_offset
, tlen
);
271 skb
->data_len
+= tlen
;
272 skb
->truesize
+= tlen
;
273 fps
->crc_eof_offset
+= sizeof(struct fcoe_crc_eof
);
275 if (fps
->crc_eof_offset
>= PAGE_SIZE
) {
276 fps
->crc_eof_page
= NULL
;
277 fps
->crc_eof_offset
= 0;
283 EXPORT_SYMBOL_GPL(fcoe_get_paged_crc_eof
);
286 * fcoe_transport_lookup - find an fcoe transport that matches a netdev
287 * @netdev: The netdev to look for from all attached transports
289 * Returns : ptr to the fcoe transport that supports this netdev or NULL
292 * The ft_mutex should be held when this is called
294 static struct fcoe_transport
*fcoe_transport_lookup(struct net_device
*netdev
)
296 struct fcoe_transport
*ft
= NULL
;
298 list_for_each_entry(ft
, &fcoe_transports
, list
)
299 if (ft
->match
&& ft
->match(netdev
))
305 * fcoe_transport_attach - Attaches an FCoE transport
306 * @ft: The fcoe transport to be attached
308 * Returns : 0 for success
310 int fcoe_transport_attach(struct fcoe_transport
*ft
)
314 mutex_lock(&ft_mutex
);
316 LIBFCOE_TRANSPORT_DBG("transport %s already attached\n",
322 /* Add default transport to the tail */
323 if (strcmp(ft
->name
, FCOE_TRANSPORT_DEFAULT
))
324 list_add(&ft
->list
, &fcoe_transports
);
326 list_add_tail(&ft
->list
, &fcoe_transports
);
329 LIBFCOE_TRANSPORT_DBG("attaching transport %s\n", ft
->name
);
332 mutex_unlock(&ft_mutex
);
335 EXPORT_SYMBOL(fcoe_transport_attach
);
338 * fcoe_transport_attach - Detaches an FCoE transport
339 * @ft: The fcoe transport to be attached
341 * Returns : 0 for success
343 int fcoe_transport_detach(struct fcoe_transport
*ft
)
347 mutex_lock(&ft_mutex
);
349 LIBFCOE_TRANSPORT_DBG("transport %s already detached\n",
356 ft
->attached
= false;
357 LIBFCOE_TRANSPORT_DBG("detaching transport %s\n", ft
->name
);
360 mutex_unlock(&ft_mutex
);
364 EXPORT_SYMBOL(fcoe_transport_detach
);
366 static int fcoe_transport_show(char *buffer
, const struct kernel_param
*kp
)
369 struct fcoe_transport
*ft
= NULL
;
371 i
= j
= sprintf(buffer
, "Attached FCoE transports:");
372 mutex_lock(&ft_mutex
);
373 list_for_each_entry(ft
, &fcoe_transports
, list
) {
374 i
+= snprintf(&buffer
[i
], IFNAMSIZ
, "%s ", ft
->name
);
378 mutex_unlock(&ft_mutex
);
380 i
+= snprintf(&buffer
[i
], IFNAMSIZ
, "none");
384 static int __init
fcoe_transport_init(void)
386 register_netdevice_notifier(&libfcoe_notifier
);
390 static int __exit
fcoe_transport_exit(void)
392 struct fcoe_transport
*ft
;
394 unregister_netdevice_notifier(&libfcoe_notifier
);
395 mutex_lock(&ft_mutex
);
396 list_for_each_entry(ft
, &fcoe_transports
, list
)
397 printk(KERN_ERR
"FCoE transport %s is still attached!\n",
399 mutex_unlock(&ft_mutex
);
404 static int fcoe_add_netdev_mapping(struct net_device
*netdev
,
405 struct fcoe_transport
*ft
)
407 struct fcoe_netdev_mapping
*nm
;
409 nm
= kmalloc(sizeof(*nm
), GFP_KERNEL
);
411 printk(KERN_ERR
"Unable to allocate netdev_mapping");
418 mutex_lock(&fn_mutex
);
419 list_add(&nm
->list
, &fcoe_netdevs
);
420 mutex_unlock(&fn_mutex
);
425 static void fcoe_del_netdev_mapping(struct net_device
*netdev
)
427 struct fcoe_netdev_mapping
*nm
= NULL
, *tmp
;
429 mutex_lock(&fn_mutex
);
430 list_for_each_entry_safe(nm
, tmp
, &fcoe_netdevs
, list
) {
431 if (nm
->netdev
== netdev
) {
434 mutex_unlock(&fn_mutex
);
438 mutex_unlock(&fn_mutex
);
443 * fcoe_netdev_map_lookup - find the fcoe transport that matches the netdev on which
446 * Returns : ptr to the fcoe transport that supports this netdev or NULL
449 * The ft_mutex should be held when this is called
451 static struct fcoe_transport
*fcoe_netdev_map_lookup(struct net_device
*netdev
)
453 struct fcoe_transport
*ft
= NULL
;
454 struct fcoe_netdev_mapping
*nm
;
456 mutex_lock(&fn_mutex
);
457 list_for_each_entry(nm
, &fcoe_netdevs
, list
) {
458 if (netdev
== nm
->netdev
) {
460 mutex_unlock(&fn_mutex
);
465 mutex_unlock(&fn_mutex
);
470 * fcoe_if_to_netdev() - Parse a name buffer to get a net device
471 * @buffer: The name of the net device
473 * Returns: NULL or a ptr to net_device
475 static struct net_device
*fcoe_if_to_netdev(const char *buffer
)
478 char ifname
[IFNAMSIZ
+ 2];
481 strlcpy(ifname
, buffer
, IFNAMSIZ
);
482 cp
= ifname
+ strlen(ifname
);
483 while (--cp
>= ifname
&& *cp
== '\n')
485 return dev_get_by_name(&init_net
, ifname
);
491 * libfcoe_device_notification() - Handler for net device events
492 * @notifier: The context of the notification
493 * @event: The type of event
494 * @ptr: The net device that the event was on
496 * This function is called by the Ethernet driver in case of link change event.
498 * Returns: 0 for success
500 static int libfcoe_device_notification(struct notifier_block
*notifier
,
501 ulong event
, void *ptr
)
503 struct net_device
*netdev
= ptr
;
506 case NETDEV_UNREGISTER
:
507 printk(KERN_ERR
"libfcoe_device_notification: NETDEV_UNREGISTER %s\n",
509 fcoe_del_netdev_mapping(netdev
);
517 * fcoe_transport_create() - Create a fcoe interface
518 * @buffer: The name of the Ethernet interface to create on
519 * @kp: The associated kernel param
521 * Called from sysfs. This holds the ft_mutex while calling the
522 * registered fcoe transport's create function.
524 * Returns: 0 for success
526 static int fcoe_transport_create(const char *buffer
, struct kernel_param
*kp
)
529 struct net_device
*netdev
= NULL
;
530 struct fcoe_transport
*ft
= NULL
;
531 enum fip_state fip_mode
= (enum fip_state
)(long)kp
->arg
;
533 if (!mutex_trylock(&ft_mutex
))
534 return restart_syscall();
536 #ifdef CONFIG_LIBFCOE_MODULE
538 * Make sure the module has been initialized, and is not about to be
539 * removed. Module parameter sysfs files are writable before the
540 * module_init function is called and after module_exit.
542 if (THIS_MODULE
->state
!= MODULE_STATE_LIVE
)
546 netdev
= fcoe_if_to_netdev(buffer
);
548 LIBFCOE_TRANSPORT_DBG("Invalid device %s.\n", buffer
);
552 ft
= fcoe_netdev_map_lookup(netdev
);
554 LIBFCOE_TRANSPORT_DBG("transport %s already has existing "
555 "FCoE instance on %s.\n",
556 ft
->name
, netdev
->name
);
561 ft
= fcoe_transport_lookup(netdev
);
563 LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
568 rc
= fcoe_add_netdev_mapping(netdev
, ft
);
570 LIBFCOE_TRANSPORT_DBG("failed to add new netdev mapping "
571 "for FCoE transport %s for %s.\n",
572 ft
->name
, netdev
->name
);
576 /* pass to transport create */
577 rc
= ft
->create
? ft
->create(netdev
, fip_mode
) : -ENODEV
;
579 fcoe_del_netdev_mapping(netdev
);
581 LIBFCOE_TRANSPORT_DBG("transport %s %s to create fcoe on %s.\n",
582 ft
->name
, (rc
) ? "failed" : "succeeded",
588 mutex_unlock(&ft_mutex
);
589 if (rc
== -ERESTARTSYS
)
590 return restart_syscall();
596 * fcoe_transport_destroy() - Destroy a FCoE interface
597 * @buffer: The name of the Ethernet interface to be destroyed
598 * @kp: The associated kernel parameter
600 * Called from sysfs. This holds the ft_mutex while calling the
601 * registered fcoe transport's destroy function.
603 * Returns: 0 for success
605 static int fcoe_transport_destroy(const char *buffer
, struct kernel_param
*kp
)
608 struct net_device
*netdev
= NULL
;
609 struct fcoe_transport
*ft
= NULL
;
611 if (!mutex_trylock(&ft_mutex
))
612 return restart_syscall();
614 #ifdef CONFIG_LIBFCOE_MODULE
616 * Make sure the module has been initialized, and is not about to be
617 * removed. Module parameter sysfs files are writable before the
618 * module_init function is called and after module_exit.
620 if (THIS_MODULE
->state
!= MODULE_STATE_LIVE
)
624 netdev
= fcoe_if_to_netdev(buffer
);
626 LIBFCOE_TRANSPORT_DBG("invalid device %s.\n", buffer
);
630 ft
= fcoe_netdev_map_lookup(netdev
);
632 LIBFCOE_TRANSPORT_DBG("no FCoE transport found for %s.\n",
637 /* pass to transport destroy */
638 rc
= ft
->destroy
? ft
->destroy(netdev
) : -ENODEV
;
639 fcoe_del_netdev_mapping(netdev
);
640 LIBFCOE_TRANSPORT_DBG("transport %s %s to destroy fcoe on %s.\n",
641 ft
->name
, (rc
) ? "failed" : "succeeded",
647 mutex_unlock(&ft_mutex
);
649 if (rc
== -ERESTARTSYS
)
650 return restart_syscall();
656 * fcoe_transport_disable() - Disables a FCoE interface
657 * @buffer: The name of the Ethernet interface to be disabled
658 * @kp: The associated kernel parameter
662 * Returns: 0 for success
664 static int fcoe_transport_disable(const char *buffer
, struct kernel_param
*kp
)
667 struct net_device
*netdev
= NULL
;
668 struct fcoe_transport
*ft
= NULL
;
670 if (!mutex_trylock(&ft_mutex
))
671 return restart_syscall();
673 #ifdef CONFIG_LIBFCOE_MODULE
675 * Make sure the module has been initialized, and is not about to be
676 * removed. Module parameter sysfs files are writable before the
677 * module_init function is called and after module_exit.
679 if (THIS_MODULE
->state
!= MODULE_STATE_LIVE
)
683 netdev
= fcoe_if_to_netdev(buffer
);
687 ft
= fcoe_netdev_map_lookup(netdev
);
691 rc
= ft
->disable
? ft
->disable(netdev
) : -ENODEV
;
696 mutex_unlock(&ft_mutex
);
698 if (rc
== -ERESTARTSYS
)
699 return restart_syscall();
705 * fcoe_transport_enable() - Enables a FCoE interface
706 * @buffer: The name of the Ethernet interface to be enabled
707 * @kp: The associated kernel parameter
711 * Returns: 0 for success
713 static int fcoe_transport_enable(const char *buffer
, struct kernel_param
*kp
)
716 struct net_device
*netdev
= NULL
;
717 struct fcoe_transport
*ft
= NULL
;
719 if (!mutex_trylock(&ft_mutex
))
720 return restart_syscall();
722 #ifdef CONFIG_LIBFCOE_MODULE
724 * Make sure the module has been initialized, and is not about to be
725 * removed. Module parameter sysfs files are writable before the
726 * module_init function is called and after module_exit.
728 if (THIS_MODULE
->state
!= MODULE_STATE_LIVE
)
732 netdev
= fcoe_if_to_netdev(buffer
);
736 ft
= fcoe_netdev_map_lookup(netdev
);
740 rc
= ft
->enable
? ft
->enable(netdev
) : -ENODEV
;
745 mutex_unlock(&ft_mutex
);
746 if (rc
== -ERESTARTSYS
)
747 return restart_syscall();
753 * libfcoe_init() - Initialization routine for libfcoe.ko
755 static int __init
libfcoe_init(void)
757 fcoe_transport_init();
761 module_init(libfcoe_init
);
764 * libfcoe_exit() - Tear down libfcoe.ko
766 static void __exit
libfcoe_exit(void)
768 fcoe_transport_exit();
770 module_exit(libfcoe_exit
);