xref: /linux/drivers/net/bonding/bond_main.c (revision 54a8a2220c936a47840c9a3d74910c5a56fae2ed)
1 /*
2  * originally based on the dummy device.
3  *
4  * Copyright 1999, Thomas Davis, tadavis@lbl.gov.
5  * Licensed under the GPL. Based on dummy.c, and eql.c devices.
6  *
7  * bonding.c: an Ethernet Bonding driver
8  *
9  * This is useful to talk to a Cisco EtherChannel compatible equipment:
10  *	Cisco 5500
11  *	Sun Trunking (Solaris)
12  *	Alteon AceDirector Trunks
13  *	Linux Bonding
14  *	and probably many L2 switches ...
15  *
16  * How it works:
17  *    ifconfig bond0 ipaddress netmask up
18  *      will setup a network device, with an ip address.  No mac address
19  *	will be assigned at this time.  The hw mac address will come from
20  *	the first slave bonded to the channel.  All slaves will then use
21  *	this hw mac address.
22  *
23  *    ifconfig bond0 down
24  *         will release all slaves, marking them as down.
25  *
26  *    ifenslave bond0 eth0
27  *	will attach eth0 to bond0 as a slave.  eth0 hw mac address will either
28  *	a: be used as initial mac address
29  *	b: if a hw mac address already is there, eth0's hw mac address
30  *	   will then be set from bond0.
31  *
32  * v0.1 - first working version.
33  * v0.2 - changed stats to be calculated by summing slaves stats.
34  *
35  * Changes:
36  * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
37  * - fix leaks on failure at bond_init
38  *
39  * 2000/09/30 - Willy Tarreau <willy at meta-x.org>
40  *     - added trivial code to release a slave device.
41  *     - fixed security bug (CAP_NET_ADMIN not checked)
42  *     - implemented MII link monitoring to disable dead links :
43  *       All MII capable slaves are checked every <miimon> milliseconds
44  *       (100 ms seems good). This value can be changed by passing it to
45  *       insmod. A value of zero disables the monitoring (default).
46  *     - fixed an infinite loop in bond_xmit_roundrobin() when there's no
47  *       good slave.
48  *     - made the code hopefully SMP safe
49  *
50  * 2000/10/03 - Willy Tarreau <willy at meta-x.org>
51  *     - optimized slave lists based on relevant suggestions from Thomas Davis
52  *     - implemented active-backup method to obtain HA with two switches:
53  *       stay as long as possible on the same active interface, while we
54  *       also monitor the backup one (MII link status) because we want to know
55  *       if we are able to switch at any time. ( pass "mode=1" to insmod )
56  *     - lots of stress testings because we need it to be more robust than the
57  *       wires ! :->
58  *
59  * 2000/10/09 - Willy Tarreau <willy at meta-x.org>
60  *     - added up and down delays after link state change.
61  *     - optimized the slaves chaining so that when we run forward, we never
62  *       repass through the bond itself, but we can find it by searching
63  *       backwards. Renders the deletion more difficult, but accelerates the
64  *       scan.
65  *     - smarter enslaving and releasing.
66  *     - finer and more robust SMP locking
67  *
68  * 2000/10/17 - Willy Tarreau <willy at meta-x.org>
69  *     - fixed two potential SMP race conditions
70  *
71  * 2000/10/18 - Willy Tarreau <willy at meta-x.org>
72  *     - small fixes to the monitoring FSM in case of zero delays
73  * 2000/11/01 - Willy Tarreau <willy at meta-x.org>
74  *     - fixed first slave not automatically used in trunk mode.
75  * 2000/11/10 : spelling of "EtherChannel" corrected.
76  * 2000/11/13 : fixed a race condition in case of concurrent accesses to ioctl().
77  * 2000/12/16 : fixed improper usage of rtnl_exlock_nowait().
78  *
79  * 2001/1/3 - Chad N. Tindel <ctindel at ieee dot org>
80  *     - The bonding driver now simulates MII status monitoring, just like
81  *       a normal network device.  It will show that the link is down iff
82  *       every slave in the bond shows that their links are down.  If at least
83  *       one slave is up, the bond's MII status will appear as up.
84  *
85  * 2001/2/7 - Chad N. Tindel <ctindel at ieee dot org>
86  *     - Applications can now query the bond from user space to get
87  *       information which may be useful.  They do this by calling
88  *       the BOND_INFO_QUERY ioctl.  Once the app knows how many slaves
89  *       are in the bond, it can call the BOND_SLAVE_INFO_QUERY ioctl to
90  *       get slave specific information (# link failures, etc).  See
91  *       <linux/if_bonding.h> for more details.  The structs of interest
92  *       are ifbond and ifslave.
93  *
94  * 2001/4/5 - Chad N. Tindel <ctindel at ieee dot org>
95  *     - Ported to 2.4 Kernel
96  *
97  * 2001/5/2 - Jeffrey E. Mast <jeff at mastfamily dot com>
98  *     - When a device is detached from a bond, the slave device is no longer
99  *       left thinking that is has a master.
100  *
101  * 2001/5/16 - Jeffrey E. Mast <jeff at mastfamily dot com>
102  *     - memset did not appropriately initialized the bond rw_locks. Used
103  *       rwlock_init to initialize to unlocked state to prevent deadlock when
104  *       first attempting a lock
105  *     - Called SET_MODULE_OWNER for bond device
106  *
107  * 2001/5/17 - Tim Anderson <tsa at mvista.com>
108  *     - 2 paths for releasing for slave release; 1 through ioctl
109  *       and 2) through close. Both paths need to release the same way.
110  *     - the free slave in bond release is changing slave status before
111  *       the free. The netdev_set_master() is intended to change slave state
112  *       so it should not be done as part of the release process.
113  *     - Simple rule for slave state at release: only the active in A/B and
114  *       only one in the trunked case.
115  *
116  * 2001/6/01 - Tim Anderson <tsa at mvista.com>
117  *     - Now call dev_close when releasing a slave so it doesn't screw up
118  *       out routing table.
119  *
120  * 2001/6/01 - Chad N. Tindel <ctindel at ieee dot org>
121  *     - Added /proc support for getting bond and slave information.
122  *       Information is in /proc/net/<bond device>/info.
123  *     - Changed the locking when calling bond_close to prevent deadlock.
124  *
125  * 2001/8/05 - Janice Girouard <girouard at us.ibm.com>
126  *     - correct problem where refcnt of slave is not incremented in bond_ioctl
127  *       so the system hangs when halting.
128  *     - correct locking problem when unable to malloc in bond_enslave.
129  *     - adding bond_xmit_xor logic.
130  *     - adding multiple bond device support.
131  *
132  * 2001/8/13 - Erik Habbinga <erik_habbinga at hp dot com>
133  *     - correct locking problem with rtnl_exlock_nowait
134  *
135  * 2001/8/23 - Janice Girouard <girouard at us.ibm.com>
136  *     - bzero initial dev_bonds, to correct oops
137  *     - convert SIOCDEVPRIVATE to new MII ioctl calls
138  *
139  * 2001/9/13 - Takao Indoh <indou dot takao at jp dot fujitsu dot com>
140  *     - Add the BOND_CHANGE_ACTIVE ioctl implementation
141  *
142  * 2001/9/14 - Mark Huth <mhuth at mvista dot com>
143  *     - Change MII_LINK_READY to not check for end of auto-negotiation,
144  *       but only for an up link.
145  *
146  * 2001/9/20 - Chad N. Tindel <ctindel at ieee dot org>
147  *     - Add the device field to bonding_t.  Previously the net_device
148  *       corresponding to a bond wasn't available from the bonding_t
149  *       structure.
150  *
151  * 2001/9/25 - Janice Girouard <girouard at us.ibm.com>
152  *     - add arp_monitor for active backup mode
153  *
154  * 2001/10/23 - Takao Indoh <indou dot takao at jp dot fujitsu dot com>
155  *     - Various memory leak fixes
156  *
157  * 2001/11/5 - Mark Huth <mark dot huth at mvista dot com>
158  *     - Don't take rtnl lock in bond_mii_monitor as it deadlocks under
159  *       certain hotswap conditions.
160  *       Note:  this same change may be required in bond_arp_monitor ???
161  *     - Remove possibility of calling bond_sethwaddr with NULL slave_dev ptr
162  *     - Handle hot swap ethernet interface deregistration events to remove
163  *       kernel oops following hot swap of enslaved interface
164  *
165  * 2002/1/2 - Chad N. Tindel <ctindel at ieee dot org>
166  *     - Restore original slave flags at release time.
167  *
168  * 2002/02/18 - Erik Habbinga <erik_habbinga at hp dot com>
169  *     - bond_release(): calling kfree on our_slave after call to
170  *       bond_restore_slave_flags, not before
171  *     - bond_enslave(): saving slave flags into original_flags before
172  *       call to netdev_set_master, so the IFF_SLAVE flag doesn't end
173  *       up in original_flags
174  *
175  * 2002/04/05 - Mark Smith <mark.smith at comdev dot cc> and
176  *              Steve Mead <steve.mead at comdev dot cc>
177  *     - Port Gleb Natapov's multicast support patchs from 2.4.12
178  *       to 2.4.18 adding support for multicast.
179  *
180  * 2002/06/10 - Tony Cureington <tony.cureington * hp_com>
181  *     - corrected uninitialized pointer (ifr.ifr_data) in bond_check_dev_link;
182  *       actually changed function to use MIIPHY, then MIIREG, and finally
183  *       ETHTOOL to determine the link status
184  *     - fixed bad ifr_data pointer assignments in bond_ioctl
185  *     - corrected mode 1 being reported as active-backup in bond_get_info;
186  *       also added text to distinguish type of load balancing (rr or xor)
187  *     - change arp_ip_target module param from "1-12s" (array of 12 ptrs)
188  *       to "s" (a single ptr)
189  *
190  * 2002/08/30 - Jay Vosburgh <fubar at us dot ibm dot com>
191  *     - Removed acquisition of xmit_lock in set_multicast_list; caused
192  *       deadlock on SMP (lock is held by caller).
193  *     - Revamped SIOCGMIIPHY, SIOCGMIIREG portion of bond_check_dev_link().
194  *
195  * 2002/09/18 - Jay Vosburgh <fubar at us dot ibm dot com>
196  *     - Fixed up bond_check_dev_link() (and callers): removed some magic
197  *	 numbers, banished local MII_ defines, wrapped ioctl calls to
198  *	 prevent EFAULT errors
199  *
200  * 2002/9/30 - Jay Vosburgh <fubar at us dot ibm dot com>
201  *     - make sure the ip target matches the arp_target before saving the
202  *	 hw address.
203  *
204  * 2002/9/30 - Dan Eisner <eisner at 2robots dot com>
205  *     - make sure my_ip is set before taking down the link, since
206  *	 not all switches respond if the source ip is not set.
207  *
208  * 2002/10/8 - Janice Girouard <girouard at us dot ibm dot com>
209  *     - read in the local ip address when enslaving a device
210  *     - add primary support
211  *     - make sure 2*arp_interval has passed when a new device
212  *       is brought on-line before taking it down.
213  *
214  * 2002/09/11 - Philippe De Muyter <phdm at macqel dot be>
215  *     - Added bond_xmit_broadcast logic.
216  *     - Added bond_mode() support function.
217  *
218  * 2002/10/26 - Laurent Deniel <laurent.deniel at free.fr>
219  *     - allow to register multicast addresses only on active slave
220  *       (useful in active-backup mode)
221  *     - add multicast module parameter
222  *     - fix deletion of multicast groups after unloading module
223  *
224  * 2002/11/06 - Kameshwara Rayaprolu <kameshwara.rao * wipro_com>
225  *     - Changes to prevent panic from closing the device twice; if we close
226  *       the device in bond_release, we must set the original_flags to down
227  *       so it won't be closed again by the network layer.
228  *
229  * 2002/11/07 - Tony Cureington <tony.cureington * hp_com>
230  *     - Fix arp_target_hw_addr memory leak
231  *     - Created activebackup_arp_monitor function to handle arp monitoring
232  *       in active backup mode - the bond_arp_monitor had several problems...
233  *       such as allowing slaves to tx arps sequentially without any delay
234  *       for a response
235  *     - Renamed bond_arp_monitor to loadbalance_arp_monitor and re-wrote
236  *       this function to just handle arp monitoring in load-balancing mode;
237  *       it is a lot more compact now
238  *     - Changes to ensure one and only one slave transmits in active-backup
239  *       mode
240  *     - Robustesize parameters; warn users about bad combinations of
241  *       parameters; also if miimon is specified and a network driver does
242  *       not support MII or ETHTOOL, inform the user of this
243  *     - Changes to support link_failure_count when in arp monitoring mode
244  *     - Fix up/down delay reported in /proc
245  *     - Added version; log version; make version available from "modinfo -d"
246  *     - Fixed problem in bond_check_dev_link - if the first IOCTL (SIOCGMIIPH)
247  *	 failed, the ETHTOOL ioctl never got a chance
248  *
249  * 2002/11/16 - Laurent Deniel <laurent.deniel at free.fr>
250  *     - fix multicast handling in activebackup_arp_monitor
251  *     - remove one unnecessary and confusing curr_active_slave == slave test
252  *	 in activebackup_arp_monitor
253  *
254  *  2002/11/17 - Laurent Deniel <laurent.deniel at free.fr>
255  *     - fix bond_slave_info_query when slave_id = num_slaves
256  *
257  *  2002/11/19 - Janice Girouard <girouard at us dot ibm dot com>
258  *     - correct ifr_data reference.  Update ifr_data reference
259  *       to mii_ioctl_data struct values to avoid confusion.
260  *
261  *  2002/11/22 - Bert Barbe <bert.barbe at oracle dot com>
262  *      - Add support for multiple arp_ip_target
263  *
264  *  2002/12/13 - Jay Vosburgh <fubar at us dot ibm dot com>
265  *	- Changed to allow text strings for mode and multicast, e.g.,
266  *	  insmod bonding mode=active-backup.  The numbers still work.
267  *	  One change: an invalid choice will cause module load failure,
268  *	  rather than the previous behavior of just picking one.
269  *	- Minor cleanups; got rid of dup ctype stuff, atoi function
270  *
271  * 2003/02/07 - Jay Vosburgh <fubar at us dot ibm dot com>
272  *	- Added use_carrier module parameter that causes miimon to
273  *	  use netif_carrier_ok() test instead of MII/ETHTOOL ioctls.
274  *	- Minor cleanups; consolidated ioctl calls to one function.
275  *
276  * 2003/02/07 - Tony Cureington <tony.cureington * hp_com>
277  *	- Fix bond_mii_monitor() logic error that could result in
278  *	  bonding round-robin mode ignoring links after failover/recovery
279  *
280  * 2003/03/17 - Jay Vosburgh <fubar at us dot ibm dot com>
281  *	- kmalloc fix (GFP_KERNEL to GFP_ATOMIC) reported by
282  *	  Shmulik dot Hen at intel.com.
283  *	- Based on discussion on mailing list, changed use of
284  *	  update_slave_cnt(), created wrapper functions for adding/removing
285  *	  slaves, changed bond_xmit_xor() to check slave_cnt instead of
286  *	  checking slave and slave->dev (which only worked by accident).
287  *	- Misc code cleanup: get arp_send() prototype from header file,
288  *	  add max_bonds to bonding.txt.
289  *
290  * 2003/03/18 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
291  *		Shmulik Hen <shmulik.hen at intel dot com>
292  *	- Make sure only bond_attach_slave() and bond_detach_slave() can
293  *	  manipulate the slave list, including slave_cnt, even when in
294  *	  bond_release_all().
295  *	- Fixed hang in bond_release() with traffic running:
296  *	  netdev_set_master() must not be called from within the bond lock.
297  *
298  * 2003/03/18 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
299  *		Shmulik Hen <shmulik.hen at intel dot com>
300  *	- Fixed hang in bond_enslave() with traffic running:
301  *	  netdev_set_master() must not be called from within the bond lock.
302  *
303  * 2003/03/18 - Amir Noam <amir.noam at intel dot com>
304  *	- Added support for getting slave's speed and duplex via ethtool.
305  *	  Needed for 802.3ad and other future modes.
306  *
307  * 2003/03/18 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
308  *		Shmulik Hen <shmulik.hen at intel dot com>
309  *	- Enable support of modes that need to use the unique mac address of
310  *	  each slave.
311  *	  * bond_enslave(): Moved setting the slave's mac address, and
312  *	    openning it, from the application to the driver. This breaks
313  *	    backward comaptibility with old versions of ifenslave that open
314  *	     the slave before enalsving it !!!.
315  *	  * bond_release(): The driver also takes care of closing the slave
316  *	    and restoring its original mac address.
317  *	- Removed the code that restores all base driver's flags.
318  *	  Flags are automatically restored once all undo stages are done
319  *	  properly.
320  *	- Block possibility of enslaving before the master is up. This
321  *	  prevents putting the system in an unstable state.
322  *
323  * 2003/03/18 - Amir Noam <amir.noam at intel dot com>,
324  *		Tsippy Mendelson <tsippy.mendelson at intel dot com> and
325  *		Shmulik Hen <shmulik.hen at intel dot com>
326  *	- Added support for IEEE 802.3ad Dynamic link aggregation mode.
327  *
328  * 2003/05/01 - Amir Noam <amir.noam at intel dot com>
329  *	- Added ABI version control to restore compatibility between
330  *	  new/old ifenslave and new/old bonding.
331  *
332  * 2003/05/01 - Shmulik Hen <shmulik.hen at intel dot com>
333  *	- Fixed bug in bond_release_all(): save old value of curr_active_slave
334  *	  before setting it to NULL.
335  *	- Changed driver versioning scheme to include version number instead
336  *	  of release date (that is already in another field). There are 3
337  *	  fields X.Y.Z where:
338  *		X - Major version - big behavior changes
339  *		Y - Minor version - addition of features
340  *		Z - Extra version - minor changes and bug fixes
341  *	  The current version is 1.0.0 as a base line.
342  *
343  * 2003/05/01 - Tsippy Mendelson <tsippy.mendelson at intel dot com> and
344  *		Amir Noam <amir.noam at intel dot com>
345  *	- Added support for lacp_rate module param.
346  *	- Code beautification and style changes (mainly in comments).
347  *	  new version - 1.0.1
348  *
349  * 2003/05/01 - Shmulik Hen <shmulik.hen at intel dot com>
350  *	- Based on discussion on mailing list, changed locking scheme
351  *	  to use lock/unlock or lock_bh/unlock_bh appropriately instead
352  *	  of lock_irqsave/unlock_irqrestore. The new scheme helps exposing
353  *	  hidden bugs and solves system hangs that occurred due to the fact
354  *	  that holding lock_irqsave doesn't prevent softirqs from running.
355  *	  This also increases total throughput since interrupts are not
356  *	  blocked on each transmitted packets or monitor timeout.
357  *	  new version - 2.0.0
358  *
359  * 2003/05/01 - Shmulik Hen <shmulik.hen at intel dot com>
360  *	- Added support for Transmit load balancing mode.
361  *	- Concentrate all assignments of curr_active_slave to a single point
362  *	  so specific modes can take actions when the primary adapter is
363  *	  changed.
364  *	- Take the updelay parameter into consideration during bond_enslave
365  *	  since some adapters loose their link during setting the device.
366  *	- Renamed bond_3ad_link_status_changed() to
367  *	  bond_3ad_handle_link_change() for compatibility with TLB.
368  *	  new version - 2.1.0
369  *
370  * 2003/05/01 - Tsippy Mendelson <tsippy.mendelson at intel dot com>
371  *	- Added support for Adaptive load balancing mode which is
372  *	  equivalent to Transmit load balancing + Receive load balancing.
373  *	  new version - 2.2.0
374  *
375  * 2003/05/15 - Jay Vosburgh <fubar at us dot ibm dot com>
376  *	- Applied fix to activebackup_arp_monitor posted to bonding-devel
377  *	  by Tony Cureington <tony.cureington * hp_com>.  Fixes ARP
378  *	  monitor endless failover bug.  Version to 2.2.10
379  *
380  * 2003/05/20 - Amir Noam <amir.noam at intel dot com>
381  *	- Fixed bug in ABI version control - Don't commit to a specific
382  *	  ABI version if receiving unsupported ioctl commands.
383  *
384  * 2003/05/22 - Jay Vosburgh <fubar at us dot ibm dot com>
385  *	- Fix ifenslave -c causing bond to loose existing routes;
386  *	  added bond_set_mac_address() that doesn't require the
387  *	  bond to be down.
388  *	- In conjunction with fix for ifenslave -c, in
389  *	  bond_change_active(), changing to the already active slave
390  *	  is no longer an error (it successfully does nothing).
391  *
392  * 2003/06/30 - Amir Noam <amir.noam at intel dot com>
393  * 	- Fixed bond_change_active() for ALB/TLB modes.
394  *	  Version to 2.2.14.
395  *
396  * 2003/07/29 - Amir Noam <amir.noam at intel dot com>
397  * 	- Fixed ARP monitoring bug.
398  *	  Version to 2.2.15.
399  *
400  * 2003/07/31 - Willy Tarreau <willy at ods dot org>
401  * 	- Fixed kernel panic when using ARP monitoring without
402  *	  setting bond's IP address.
403  *	  Version to 2.2.16.
404  *
405  * 2003/08/06 - Amir Noam <amir.noam at intel dot com>
406  * 	- Back port from 2.6: use alloc_netdev(); fix /proc handling;
407  *	  made stats a part of bond struct so no need to allocate
408  *	  and free it separately; use standard list operations instead
409  *	  of pre-allocated array of bonds.
410  *	  Version to 2.3.0.
411  *
412  * 2003/08/07 - Jay Vosburgh <fubar at us dot ibm dot com>,
413  *	       Amir Noam <amir.noam at intel dot com> and
414  *	       Shmulik Hen <shmulik.hen at intel dot com>
415  *	- Propagating master's settings: Distinguish between modes that
416  *	  use a primary slave from those that don't, and propagate settings
417  *	  accordingly; Consolidate change_active opeartions and add
418  *	  reselect_active and find_best opeartions; Decouple promiscuous
419  *	  handling from the multicast mode setting; Add support for changing
420  *	  HW address and MTU with proper unwind; Consolidate procfs code,
421  *	  add CHANGENAME handler; Enhance netdev notification handling.
422  *	  Version to 2.4.0.
423  *
424  * 2003/09/15 - Stephen Hemminger <shemminger at osdl dot org>,
425  *	       Amir Noam <amir.noam at intel dot com>
426  *	- Convert /proc to seq_file interface.
427  *	  Change /proc/net/bondX/info to /proc/net/bonding/bondX.
428  *	  Set version to 2.4.1.
429  *
430  * 2003/11/20 - Amir Noam <amir.noam at intel dot com>
431  *	- Fix /proc creation/destruction.
432  *
433  * 2003/12/01 - Shmulik Hen <shmulik.hen at intel dot com>
434  *	- Massive cleanup - Set version to 2.5.0
435  *	  Code changes:
436  *	  o Consolidate format of prints and debug prints.
437  *	  o Remove bonding_t/slave_t typedefs and consolidate all casts.
438  *	  o Remove dead code and unnecessary checks.
439  *	  o Consolidate starting/stopping timers.
440  *	  o Consolidate handling of primary module param throughout the code.
441  *	  o Removed multicast module param support - all settings are done
442  *	    according to mode.
443  *	  o Slave list iteration - bond is no longer part of the list,
444  *	    added cyclic list iteration macros.
445  *	  o Consolidate error handling in all xmit functions.
446  *	  Style changes:
447  *	  o Consolidate function naming and declarations.
448  *	  o Consolidate function params and local variables names.
449  *	  o Consolidate return values.
450  *	  o Consolidate curly braces.
451  *	  o Consolidate conditionals format.
452  *	  o Change struct member names and types.
453  *	  o Chomp trailing spaces, remove empty lines, fix indentations.
454  *	  o Re-organize code according to context.
455  *
456  * 2003/12/30 - Amir Noam <amir.noam at intel dot com>
457  *	- Fixed: Cannot remove and re-enslave the original active slave.
458  *	- Fixed: Releasing the original active slave causes mac address
459  *		 duplication.
460  *	- Add support for slaves that use ethtool_ops.
461  *	  Set version to 2.5.3.
462  *
463  * 2004/01/05 - Amir Noam <amir.noam at intel dot com>
464  *	- Save bonding parameters per bond instead of using the global values.
465  *	  Set version to 2.5.4.
466  *
467  * 2004/01/14 - Shmulik Hen <shmulik.hen at intel dot com>
468  *	- Enhance VLAN support:
469  *	  * Add support for VLAN hardware acceleration capable slaves.
470  *	  * Add capability to tag self generated packets in ALB/TLB modes.
471  *	  Set version to 2.6.0.
472  * 2004/10/29 - Mitch Williams <mitch.a.williams at intel dot com>
473  *      - Fixed bug when unloading module while using 802.3ad.  If
474  *        spinlock debugging is turned on, this causes a stack dump.
475  *        Solution is to move call to dev_remove_pack outside of the
476  *        spinlock.
477  *        Set version to 2.6.1.
478  * 2005/06/05 - Jay Vosburgh <fubar@us.ibm.com>
479  * 	- Support for generating gratuitous ARPs in active-backup mode.
480  * 	  Includes support for VLAN tagging all bonding-generated ARPs
481  * 	  as needed.  Set version to 2.6.2.
482  * 2005/06/08 - Jason Gabler <jygabler at lbl dot gov>
483  *	- alternate hashing policy support for mode 2
484  *	  * Added kernel parameter "xmit_hash_policy" to allow the selection
485  *	    of different hashing policies for mode 2.  The original mode 2
486  *	    policy is the default, now found in xmit_hash_policy_layer2().
487  *	  * Added xmit_hash_policy_layer34()
488  *	- Modified by Jay Vosburgh <fubar@us.ibm.com> to also support mode 4.
489  *	  Set version to 2.6.3.
490  * 2005/09/26 - Jay Vosburgh <fubar@us.ibm.com>
491  *	- Removed backwards compatibility for old ifenslaves.  Version 2.6.4.
492  */
493 
494 //#define BONDING_DEBUG 1
495 
496 #include <linux/config.h>
497 #include <linux/kernel.h>
498 #include <linux/module.h>
499 #include <linux/sched.h>
500 #include <linux/types.h>
501 #include <linux/fcntl.h>
502 #include <linux/interrupt.h>
503 #include <linux/ptrace.h>
504 #include <linux/ioport.h>
505 #include <linux/in.h>
506 #include <net/ip.h>
507 #include <linux/ip.h>
508 #include <linux/tcp.h>
509 #include <linux/udp.h>
510 #include <linux/slab.h>
511 #include <linux/string.h>
512 #include <linux/init.h>
513 #include <linux/timer.h>
514 #include <linux/socket.h>
515 #include <linux/ctype.h>
516 #include <linux/inet.h>
517 #include <linux/bitops.h>
518 #include <asm/system.h>
519 #include <asm/io.h>
520 #include <asm/dma.h>
521 #include <asm/uaccess.h>
522 #include <linux/errno.h>
523 #include <linux/netdevice.h>
524 #include <linux/inetdevice.h>
525 #include <linux/etherdevice.h>
526 #include <linux/skbuff.h>
527 #include <net/sock.h>
528 #include <linux/rtnetlink.h>
529 #include <linux/proc_fs.h>
530 #include <linux/seq_file.h>
531 #include <linux/smp.h>
532 #include <linux/if_ether.h>
533 #include <net/arp.h>
534 #include <linux/mii.h>
535 #include <linux/ethtool.h>
536 #include <linux/if_vlan.h>
537 #include <linux/if_bonding.h>
538 #include <net/route.h>
539 #include "bonding.h"
540 #include "bond_3ad.h"
541 #include "bond_alb.h"
542 
543 /*---------------------------- Module parameters ----------------------------*/
544 
545 /* monitor all links that often (in milliseconds). <=0 disables monitoring */
546 #define BOND_LINK_MON_INTERV	0
547 #define BOND_LINK_ARP_INTERV	0
548 
549 static int max_bonds	= BOND_DEFAULT_MAX_BONDS;
550 static int miimon	= BOND_LINK_MON_INTERV;
551 static int updelay	= 0;
552 static int downdelay	= 0;
553 static int use_carrier	= 1;
554 static char *mode	= NULL;
555 static char *primary	= NULL;
556 static char *lacp_rate	= NULL;
557 static char *xmit_hash_policy = NULL;
558 static int arp_interval = BOND_LINK_ARP_INTERV;
559 static char *arp_ip_target[BOND_MAX_ARP_TARGETS] = { NULL, };
560 
561 module_param(max_bonds, int, 0);
562 MODULE_PARM_DESC(max_bonds, "Max number of bonded devices");
563 module_param(miimon, int, 0);
564 MODULE_PARM_DESC(miimon, "Link check interval in milliseconds");
565 module_param(updelay, int, 0);
566 MODULE_PARM_DESC(updelay, "Delay before considering link up, in milliseconds");
567 module_param(downdelay, int, 0);
568 MODULE_PARM_DESC(downdelay, "Delay before considering link down, in milliseconds");
569 module_param(use_carrier, int, 0);
570 MODULE_PARM_DESC(use_carrier, "Use netif_carrier_ok (vs MII ioctls) in miimon; 0 for off, 1 for on (default)");
571 module_param(mode, charp, 0);
572 MODULE_PARM_DESC(mode, "Mode of operation : 0 for round robin, 1 for active-backup, 2 for xor");
573 module_param(primary, charp, 0);
574 MODULE_PARM_DESC(primary, "Primary network device to use");
575 module_param(lacp_rate, charp, 0);
576 MODULE_PARM_DESC(lacp_rate, "LACPDU tx rate to request from 802.3ad partner (slow/fast)");
577 module_param(xmit_hash_policy, charp, 0);
578 MODULE_PARM_DESC(xmit_hash_policy, "XOR hashing method : 0 for layer 2 (default), 1 for layer 3+4");
579 module_param(arp_interval, int, 0);
580 MODULE_PARM_DESC(arp_interval, "arp interval in milliseconds");
581 module_param_array(arp_ip_target, charp, NULL, 0);
582 MODULE_PARM_DESC(arp_ip_target, "arp targets in n.n.n.n form");
583 
584 /*----------------------------- Global variables ----------------------------*/
585 
586 static const char *version =
587 	DRV_DESCRIPTION ": v" DRV_VERSION " (" DRV_RELDATE ")\n";
588 
589 static LIST_HEAD(bond_dev_list);
590 
591 #ifdef CONFIG_PROC_FS
592 static struct proc_dir_entry *bond_proc_dir = NULL;
593 #endif
594 
595 static u32 arp_target[BOND_MAX_ARP_TARGETS] = { 0, } ;
596 static int arp_ip_count	= 0;
597 static int bond_mode	= BOND_MODE_ROUNDROBIN;
598 static int xmit_hashtype= BOND_XMIT_POLICY_LAYER2;
599 static int lacp_fast	= 0;
600 
601 struct bond_parm_tbl {
602 	char *modename;
603 	int mode;
604 };
605 
606 static struct bond_parm_tbl bond_lacp_tbl[] = {
607 {	"slow",		AD_LACP_SLOW},
608 {	"fast",		AD_LACP_FAST},
609 {	NULL,		-1},
610 };
611 
612 static struct bond_parm_tbl bond_mode_tbl[] = {
613 {	"balance-rr",		BOND_MODE_ROUNDROBIN},
614 {	"active-backup",	BOND_MODE_ACTIVEBACKUP},
615 {	"balance-xor",		BOND_MODE_XOR},
616 {	"broadcast",		BOND_MODE_BROADCAST},
617 {	"802.3ad",		BOND_MODE_8023AD},
618 {	"balance-tlb",		BOND_MODE_TLB},
619 {	"balance-alb",		BOND_MODE_ALB},
620 {	NULL,			-1},
621 };
622 
623 static struct bond_parm_tbl xmit_hashtype_tbl[] = {
624 {	"layer2",		BOND_XMIT_POLICY_LAYER2},
625 {	"layer3+4",		BOND_XMIT_POLICY_LAYER34},
626 {	NULL,			-1},
627 };
628 
629 /*-------------------------- Forward declarations ---------------------------*/
630 
631 static inline void bond_set_mode_ops(struct bonding *bond, int mode);
632 static void bond_send_gratuitous_arp(struct bonding *bond);
633 
634 /*---------------------------- General routines -----------------------------*/
635 
636 static const char *bond_mode_name(int mode)
637 {
638 	switch (mode) {
639 	case BOND_MODE_ROUNDROBIN :
640 		return "load balancing (round-robin)";
641 	case BOND_MODE_ACTIVEBACKUP :
642 		return "fault-tolerance (active-backup)";
643 	case BOND_MODE_XOR :
644 		return "load balancing (xor)";
645 	case BOND_MODE_BROADCAST :
646 		return "fault-tolerance (broadcast)";
647 	case BOND_MODE_8023AD:
648 		return "IEEE 802.3ad Dynamic link aggregation";
649 	case BOND_MODE_TLB:
650 		return "transmit load balancing";
651 	case BOND_MODE_ALB:
652 		return "adaptive load balancing";
653 	default:
654 		return "unknown";
655 	}
656 }
657 
658 /*---------------------------------- VLAN -----------------------------------*/
659 
660 /**
661  * bond_add_vlan - add a new vlan id on bond
662  * @bond: bond that got the notification
663  * @vlan_id: the vlan id to add
664  *
665  * Returns -ENOMEM if allocation failed.
666  */
667 static int bond_add_vlan(struct bonding *bond, unsigned short vlan_id)
668 {
669 	struct vlan_entry *vlan;
670 
671 	dprintk("bond: %s, vlan id %d\n",
672 		(bond ? bond->dev->name: "None"), vlan_id);
673 
674 	vlan = kmalloc(sizeof(struct vlan_entry), GFP_KERNEL);
675 	if (!vlan) {
676 		return -ENOMEM;
677 	}
678 
679 	INIT_LIST_HEAD(&vlan->vlan_list);
680 	vlan->vlan_id = vlan_id;
681 	vlan->vlan_ip = 0;
682 
683 	write_lock_bh(&bond->lock);
684 
685 	list_add_tail(&vlan->vlan_list, &bond->vlan_list);
686 
687 	write_unlock_bh(&bond->lock);
688 
689 	dprintk("added VLAN ID %d on bond %s\n", vlan_id, bond->dev->name);
690 
691 	return 0;
692 }
693 
694 /**
695  * bond_del_vlan - delete a vlan id from bond
696  * @bond: bond that got the notification
697  * @vlan_id: the vlan id to delete
698  *
699  * returns -ENODEV if @vlan_id was not found in @bond.
700  */
701 static int bond_del_vlan(struct bonding *bond, unsigned short vlan_id)
702 {
703 	struct vlan_entry *vlan, *next;
704 	int res = -ENODEV;
705 
706 	dprintk("bond: %s, vlan id %d\n", bond->dev->name, vlan_id);
707 
708 	write_lock_bh(&bond->lock);
709 
710 	list_for_each_entry_safe(vlan, next, &bond->vlan_list, vlan_list) {
711 		if (vlan->vlan_id == vlan_id) {
712 			list_del(&vlan->vlan_list);
713 
714 			if ((bond->params.mode == BOND_MODE_TLB) ||
715 			    (bond->params.mode == BOND_MODE_ALB)) {
716 				bond_alb_clear_vlan(bond, vlan_id);
717 			}
718 
719 			dprintk("removed VLAN ID %d from bond %s\n", vlan_id,
720 				bond->dev->name);
721 
722 			kfree(vlan);
723 
724 			if (list_empty(&bond->vlan_list) &&
725 			    (bond->slave_cnt == 0)) {
726 				/* Last VLAN removed and no slaves, so
727 				 * restore block on adding VLANs. This will
728 				 * be removed once new slaves that are not
729 				 * VLAN challenged will be added.
730 				 */
731 				bond->dev->features |= NETIF_F_VLAN_CHALLENGED;
732 			}
733 
734 			res = 0;
735 			goto out;
736 		}
737 	}
738 
739 	dprintk("couldn't find VLAN ID %d in bond %s\n", vlan_id,
740 		bond->dev->name);
741 
742 out:
743 	write_unlock_bh(&bond->lock);
744 	return res;
745 }
746 
747 /**
748  * bond_has_challenged_slaves
749  * @bond: the bond we're working on
750  *
751  * Searches the slave list. Returns 1 if a vlan challenged slave
752  * was found, 0 otherwise.
753  *
754  * Assumes bond->lock is held.
755  */
756 static int bond_has_challenged_slaves(struct bonding *bond)
757 {
758 	struct slave *slave;
759 	int i;
760 
761 	bond_for_each_slave(bond, slave, i) {
762 		if (slave->dev->features & NETIF_F_VLAN_CHALLENGED) {
763 			dprintk("found VLAN challenged slave - %s\n",
764 				slave->dev->name);
765 			return 1;
766 		}
767 	}
768 
769 	dprintk("no VLAN challenged slaves found\n");
770 	return 0;
771 }
772 
773 /**
774  * bond_next_vlan - safely skip to the next item in the vlans list.
775  * @bond: the bond we're working on
776  * @curr: item we're advancing from
777  *
778  * Returns %NULL if list is empty, bond->next_vlan if @curr is %NULL,
779  * or @curr->next otherwise (even if it is @curr itself again).
780  *
781  * Caller must hold bond->lock
782  */
783 struct vlan_entry *bond_next_vlan(struct bonding *bond, struct vlan_entry *curr)
784 {
785 	struct vlan_entry *next, *last;
786 
787 	if (list_empty(&bond->vlan_list)) {
788 		return NULL;
789 	}
790 
791 	if (!curr) {
792 		next = list_entry(bond->vlan_list.next,
793 				  struct vlan_entry, vlan_list);
794 	} else {
795 		last = list_entry(bond->vlan_list.prev,
796 				  struct vlan_entry, vlan_list);
797 		if (last == curr) {
798 			next = list_entry(bond->vlan_list.next,
799 					  struct vlan_entry, vlan_list);
800 		} else {
801 			next = list_entry(curr->vlan_list.next,
802 					  struct vlan_entry, vlan_list);
803 		}
804 	}
805 
806 	return next;
807 }
808 
809 /**
810  * bond_dev_queue_xmit - Prepare skb for xmit.
811  *
812  * @bond: bond device that got this skb for tx.
813  * @skb: hw accel VLAN tagged skb to transmit
814  * @slave_dev: slave that is supposed to xmit this skbuff
815  *
816  * When the bond gets an skb to transmit that is
817  * already hardware accelerated VLAN tagged, and it
818  * needs to relay this skb to a slave that is not
819  * hw accel capable, the skb needs to be "unaccelerated",
820  * i.e. strip the hwaccel tag and re-insert it as part
821  * of the payload.
822  */
823 int bond_dev_queue_xmit(struct bonding *bond, struct sk_buff *skb, struct net_device *slave_dev)
824 {
825 	unsigned short vlan_id;
826 
827 	if (!list_empty(&bond->vlan_list) &&
828 	    !(slave_dev->features & NETIF_F_HW_VLAN_TX) &&
829 	    vlan_get_tag(skb, &vlan_id) == 0) {
830 		skb->dev = slave_dev;
831 		skb = vlan_put_tag(skb, vlan_id);
832 		if (!skb) {
833 			/* vlan_put_tag() frees the skb in case of error,
834 			 * so return success here so the calling functions
835 			 * won't attempt to free is again.
836 			 */
837 			return 0;
838 		}
839 	} else {
840 		skb->dev = slave_dev;
841 	}
842 
843 	skb->priority = 1;
844 	dev_queue_xmit(skb);
845 
846 	return 0;
847 }
848 
849 /*
850  * In the following 3 functions, bond_vlan_rx_register(), bond_vlan_rx_add_vid
851  * and bond_vlan_rx_kill_vid, We don't protect the slave list iteration with a
852  * lock because:
853  * a. This operation is performed in IOCTL context,
854  * b. The operation is protected by the RTNL semaphore in the 8021q code,
855  * c. Holding a lock with BH disabled while directly calling a base driver
856  *    entry point is generally a BAD idea.
857  *
858  * The design of synchronization/protection for this operation in the 8021q
859  * module is good for one or more VLAN devices over a single physical device
860  * and cannot be extended for a teaming solution like bonding, so there is a
861  * potential race condition here where a net device from the vlan group might
862  * be referenced (either by a base driver or the 8021q code) while it is being
863  * removed from the system. However, it turns out we're not making matters
864  * worse, and if it works for regular VLAN usage it will work here too.
865 */
866 
867 /**
868  * bond_vlan_rx_register - Propagates registration to slaves
869  * @bond_dev: bonding net device that got called
870  * @grp: vlan group being registered
871  */
872 static void bond_vlan_rx_register(struct net_device *bond_dev, struct vlan_group *grp)
873 {
874 	struct bonding *bond = bond_dev->priv;
875 	struct slave *slave;
876 	int i;
877 
878 	bond->vlgrp = grp;
879 
880 	bond_for_each_slave(bond, slave, i) {
881 		struct net_device *slave_dev = slave->dev;
882 
883 		if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
884 		    slave_dev->vlan_rx_register) {
885 			slave_dev->vlan_rx_register(slave_dev, grp);
886 		}
887 	}
888 }
889 
890 /**
891  * bond_vlan_rx_add_vid - Propagates adding an id to slaves
892  * @bond_dev: bonding net device that got called
893  * @vid: vlan id being added
894  */
895 static void bond_vlan_rx_add_vid(struct net_device *bond_dev, uint16_t vid)
896 {
897 	struct bonding *bond = bond_dev->priv;
898 	struct slave *slave;
899 	int i, res;
900 
901 	bond_for_each_slave(bond, slave, i) {
902 		struct net_device *slave_dev = slave->dev;
903 
904 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
905 		    slave_dev->vlan_rx_add_vid) {
906 			slave_dev->vlan_rx_add_vid(slave_dev, vid);
907 		}
908 	}
909 
910 	res = bond_add_vlan(bond, vid);
911 	if (res) {
912 		printk(KERN_ERR DRV_NAME
913 		       ": %s: Failed to add vlan id %d\n",
914 		       bond_dev->name, vid);
915 	}
916 }
917 
918 /**
919  * bond_vlan_rx_kill_vid - Propagates deleting an id to slaves
920  * @bond_dev: bonding net device that got called
921  * @vid: vlan id being removed
922  */
923 static void bond_vlan_rx_kill_vid(struct net_device *bond_dev, uint16_t vid)
924 {
925 	struct bonding *bond = bond_dev->priv;
926 	struct slave *slave;
927 	struct net_device *vlan_dev;
928 	int i, res;
929 
930 	bond_for_each_slave(bond, slave, i) {
931 		struct net_device *slave_dev = slave->dev;
932 
933 		if ((slave_dev->features & NETIF_F_HW_VLAN_FILTER) &&
934 		    slave_dev->vlan_rx_kill_vid) {
935 			/* Save and then restore vlan_dev in the grp array,
936 			 * since the slave's driver might clear it.
937 			 */
938 			vlan_dev = bond->vlgrp->vlan_devices[vid];
939 			slave_dev->vlan_rx_kill_vid(slave_dev, vid);
940 			bond->vlgrp->vlan_devices[vid] = vlan_dev;
941 		}
942 	}
943 
944 	res = bond_del_vlan(bond, vid);
945 	if (res) {
946 		printk(KERN_ERR DRV_NAME
947 		       ": %s: Failed to remove vlan id %d\n",
948 		       bond_dev->name, vid);
949 	}
950 }
951 
952 static void bond_add_vlans_on_slave(struct bonding *bond, struct net_device *slave_dev)
953 {
954 	struct vlan_entry *vlan;
955 
956 	write_lock_bh(&bond->lock);
957 
958 	if (list_empty(&bond->vlan_list)) {
959 		goto out;
960 	}
961 
962 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
963 	    slave_dev->vlan_rx_register) {
964 		slave_dev->vlan_rx_register(slave_dev, bond->vlgrp);
965 	}
966 
967 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
968 	    !(slave_dev->vlan_rx_add_vid)) {
969 		goto out;
970 	}
971 
972 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
973 		slave_dev->vlan_rx_add_vid(slave_dev, vlan->vlan_id);
974 	}
975 
976 out:
977 	write_unlock_bh(&bond->lock);
978 }
979 
980 static void bond_del_vlans_from_slave(struct bonding *bond, struct net_device *slave_dev)
981 {
982 	struct vlan_entry *vlan;
983 	struct net_device *vlan_dev;
984 
985 	write_lock_bh(&bond->lock);
986 
987 	if (list_empty(&bond->vlan_list)) {
988 		goto out;
989 	}
990 
991 	if (!(slave_dev->features & NETIF_F_HW_VLAN_FILTER) ||
992 	    !(slave_dev->vlan_rx_kill_vid)) {
993 		goto unreg;
994 	}
995 
996 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
997 		/* Save and then restore vlan_dev in the grp array,
998 		 * since the slave's driver might clear it.
999 		 */
1000 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
1001 		slave_dev->vlan_rx_kill_vid(slave_dev, vlan->vlan_id);
1002 		bond->vlgrp->vlan_devices[vlan->vlan_id] = vlan_dev;
1003 	}
1004 
1005 unreg:
1006 	if ((slave_dev->features & NETIF_F_HW_VLAN_RX) &&
1007 	    slave_dev->vlan_rx_register) {
1008 		slave_dev->vlan_rx_register(slave_dev, NULL);
1009 	}
1010 
1011 out:
1012 	write_unlock_bh(&bond->lock);
1013 }
1014 
1015 /*------------------------------- Link status -------------------------------*/
1016 
1017 /*
1018  * Get link speed and duplex from the slave's base driver
1019  * using ethtool. If for some reason the call fails or the
1020  * values are invalid, fake speed and duplex to 100/Full
1021  * and return error.
1022  */
1023 static int bond_update_speed_duplex(struct slave *slave)
1024 {
1025 	struct net_device *slave_dev = slave->dev;
1026 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
1027 	struct ifreq ifr;
1028 	struct ethtool_cmd etool;
1029 
1030 	/* Fake speed and duplex */
1031 	slave->speed = SPEED_100;
1032 	slave->duplex = DUPLEX_FULL;
1033 
1034 	if (slave_dev->ethtool_ops) {
1035 		u32 res;
1036 
1037 		if (!slave_dev->ethtool_ops->get_settings) {
1038 			return -1;
1039 		}
1040 
1041 		res = slave_dev->ethtool_ops->get_settings(slave_dev, &etool);
1042 		if (res < 0) {
1043 			return -1;
1044 		}
1045 
1046 		goto verify;
1047 	}
1048 
1049 	ioctl = slave_dev->do_ioctl;
1050 	strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
1051 	etool.cmd = ETHTOOL_GSET;
1052 	ifr.ifr_data = (char*)&etool;
1053 	if (!ioctl || (IOCTL(slave_dev, &ifr, SIOCETHTOOL) < 0)) {
1054 		return -1;
1055 	}
1056 
1057 verify:
1058 	switch (etool.speed) {
1059 	case SPEED_10:
1060 	case SPEED_100:
1061 	case SPEED_1000:
1062 		break;
1063 	default:
1064 		return -1;
1065 	}
1066 
1067 	switch (etool.duplex) {
1068 	case DUPLEX_FULL:
1069 	case DUPLEX_HALF:
1070 		break;
1071 	default:
1072 		return -1;
1073 	}
1074 
1075 	slave->speed = etool.speed;
1076 	slave->duplex = etool.duplex;
1077 
1078 	return 0;
1079 }
1080 
1081 /*
1082  * if <dev> supports MII link status reporting, check its link status.
1083  *
1084  * We either do MII/ETHTOOL ioctls, or check netif_carrier_ok(),
1085  * depening upon the setting of the use_carrier parameter.
1086  *
1087  * Return either BMSR_LSTATUS, meaning that the link is up (or we
1088  * can't tell and just pretend it is), or 0, meaning that the link is
1089  * down.
1090  *
1091  * If reporting is non-zero, instead of faking link up, return -1 if
1092  * both ETHTOOL and MII ioctls fail (meaning the device does not
1093  * support them).  If use_carrier is set, return whatever it says.
1094  * It'd be nice if there was a good way to tell if a driver supports
1095  * netif_carrier, but there really isn't.
1096  */
1097 static int bond_check_dev_link(struct bonding *bond, struct net_device *slave_dev, int reporting)
1098 {
1099 	static int (* ioctl)(struct net_device *, struct ifreq *, int);
1100 	struct ifreq ifr;
1101 	struct mii_ioctl_data *mii;
1102 	struct ethtool_value etool;
1103 
1104 	if (bond->params.use_carrier) {
1105 		return netif_carrier_ok(slave_dev) ? BMSR_LSTATUS : 0;
1106 	}
1107 
1108 	ioctl = slave_dev->do_ioctl;
1109 	if (ioctl) {
1110 		/* TODO: set pointer to correct ioctl on a per team member */
1111 		/*       bases to make this more efficient. that is, once  */
1112 		/*       we determine the correct ioctl, we will always    */
1113 		/*       call it and not the others for that team          */
1114 		/*       member.                                           */
1115 
1116 		/*
1117 		 * We cannot assume that SIOCGMIIPHY will also read a
1118 		 * register; not all network drivers (e.g., e100)
1119 		 * support that.
1120 		 */
1121 
1122 		/* Yes, the mii is overlaid on the ifreq.ifr_ifru */
1123 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
1124 		mii = if_mii(&ifr);
1125 		if (IOCTL(slave_dev, &ifr, SIOCGMIIPHY) == 0) {
1126 			mii->reg_num = MII_BMSR;
1127 			if (IOCTL(slave_dev, &ifr, SIOCGMIIREG) == 0) {
1128 				return (mii->val_out & BMSR_LSTATUS);
1129 			}
1130 		}
1131 	}
1132 
1133 	/* try SIOCETHTOOL ioctl, some drivers cache ETHTOOL_GLINK */
1134 	/* for a period of time so we attempt to get link status   */
1135 	/* from it last if the above MII ioctls fail...            */
1136 	if (slave_dev->ethtool_ops) {
1137 		if (slave_dev->ethtool_ops->get_link) {
1138 			u32 link;
1139 
1140 			link = slave_dev->ethtool_ops->get_link(slave_dev);
1141 
1142 			return link ? BMSR_LSTATUS : 0;
1143 		}
1144 	}
1145 
1146 	if (ioctl) {
1147 		strncpy(ifr.ifr_name, slave_dev->name, IFNAMSIZ);
1148 		etool.cmd = ETHTOOL_GLINK;
1149 		ifr.ifr_data = (char*)&etool;
1150 		if (IOCTL(slave_dev, &ifr, SIOCETHTOOL) == 0) {
1151 			if (etool.data == 1) {
1152 				return BMSR_LSTATUS;
1153 			} else {
1154 				dprintk("SIOCETHTOOL shows link down\n");
1155 				return 0;
1156 			}
1157 		}
1158 	}
1159 
1160 	/*
1161 	 * If reporting, report that either there's no dev->do_ioctl,
1162 	 * or both SIOCGMIIREG and SIOCETHTOOL failed (meaning that we
1163 	 * cannot report link status).  If not reporting, pretend
1164 	 * we're ok.
1165 	 */
1166 	return (reporting ? -1 : BMSR_LSTATUS);
1167 }
1168 
1169 /*----------------------------- Multicast list ------------------------------*/
1170 
1171 /*
1172  * Returns 0 if dmi1 and dmi2 are the same, non-0 otherwise
1173  */
1174 static inline int bond_is_dmi_same(struct dev_mc_list *dmi1, struct dev_mc_list *dmi2)
1175 {
1176 	return memcmp(dmi1->dmi_addr, dmi2->dmi_addr, dmi1->dmi_addrlen) == 0 &&
1177 			dmi1->dmi_addrlen == dmi2->dmi_addrlen;
1178 }
1179 
1180 /*
1181  * returns dmi entry if found, NULL otherwise
1182  */
1183 static struct dev_mc_list *bond_mc_list_find_dmi(struct dev_mc_list *dmi, struct dev_mc_list *mc_list)
1184 {
1185 	struct dev_mc_list *idmi;
1186 
1187 	for (idmi = mc_list; idmi; idmi = idmi->next) {
1188 		if (bond_is_dmi_same(dmi, idmi)) {
1189 			return idmi;
1190 		}
1191 	}
1192 
1193 	return NULL;
1194 }
1195 
1196 /*
1197  * Push the promiscuity flag down to appropriate slaves
1198  */
1199 static void bond_set_promiscuity(struct bonding *bond, int inc)
1200 {
1201 	if (USES_PRIMARY(bond->params.mode)) {
1202 		/* write lock already acquired */
1203 		if (bond->curr_active_slave) {
1204 			dev_set_promiscuity(bond->curr_active_slave->dev, inc);
1205 		}
1206 	} else {
1207 		struct slave *slave;
1208 		int i;
1209 		bond_for_each_slave(bond, slave, i) {
1210 			dev_set_promiscuity(slave->dev, inc);
1211 		}
1212 	}
1213 }
1214 
1215 /*
1216  * Push the allmulti flag down to all slaves
1217  */
1218 static void bond_set_allmulti(struct bonding *bond, int inc)
1219 {
1220 	if (USES_PRIMARY(bond->params.mode)) {
1221 		/* write lock already acquired */
1222 		if (bond->curr_active_slave) {
1223 			dev_set_allmulti(bond->curr_active_slave->dev, inc);
1224 		}
1225 	} else {
1226 		struct slave *slave;
1227 		int i;
1228 		bond_for_each_slave(bond, slave, i) {
1229 			dev_set_allmulti(slave->dev, inc);
1230 		}
1231 	}
1232 }
1233 
1234 /*
1235  * Add a Multicast address to slaves
1236  * according to mode
1237  */
1238 static void bond_mc_add(struct bonding *bond, void *addr, int alen)
1239 {
1240 	if (USES_PRIMARY(bond->params.mode)) {
1241 		/* write lock already acquired */
1242 		if (bond->curr_active_slave) {
1243 			dev_mc_add(bond->curr_active_slave->dev, addr, alen, 0);
1244 		}
1245 	} else {
1246 		struct slave *slave;
1247 		int i;
1248 		bond_for_each_slave(bond, slave, i) {
1249 			dev_mc_add(slave->dev, addr, alen, 0);
1250 		}
1251 	}
1252 }
1253 
1254 /*
1255  * Remove a multicast address from slave
1256  * according to mode
1257  */
1258 static void bond_mc_delete(struct bonding *bond, void *addr, int alen)
1259 {
1260 	if (USES_PRIMARY(bond->params.mode)) {
1261 		/* write lock already acquired */
1262 		if (bond->curr_active_slave) {
1263 			dev_mc_delete(bond->curr_active_slave->dev, addr, alen, 0);
1264 		}
1265 	} else {
1266 		struct slave *slave;
1267 		int i;
1268 		bond_for_each_slave(bond, slave, i) {
1269 			dev_mc_delete(slave->dev, addr, alen, 0);
1270 		}
1271 	}
1272 }
1273 
1274 /*
1275  * Totally destroys the mc_list in bond
1276  */
1277 static void bond_mc_list_destroy(struct bonding *bond)
1278 {
1279 	struct dev_mc_list *dmi;
1280 
1281 	dmi = bond->mc_list;
1282 	while (dmi) {
1283 		bond->mc_list = dmi->next;
1284 		kfree(dmi);
1285 		dmi = bond->mc_list;
1286 	}
1287 }
1288 
1289 /*
1290  * Copy all the Multicast addresses from src to the bonding device dst
1291  */
1292 static int bond_mc_list_copy(struct dev_mc_list *mc_list, struct bonding *bond,
1293 			     gfp_t gfp_flag)
1294 {
1295 	struct dev_mc_list *dmi, *new_dmi;
1296 
1297 	for (dmi = mc_list; dmi; dmi = dmi->next) {
1298 		new_dmi = kmalloc(sizeof(struct dev_mc_list), gfp_flag);
1299 
1300 		if (!new_dmi) {
1301 			/* FIXME: Potential memory leak !!! */
1302 			return -ENOMEM;
1303 		}
1304 
1305 		new_dmi->next = bond->mc_list;
1306 		bond->mc_list = new_dmi;
1307 		new_dmi->dmi_addrlen = dmi->dmi_addrlen;
1308 		memcpy(new_dmi->dmi_addr, dmi->dmi_addr, dmi->dmi_addrlen);
1309 		new_dmi->dmi_users = dmi->dmi_users;
1310 		new_dmi->dmi_gusers = dmi->dmi_gusers;
1311 	}
1312 
1313 	return 0;
1314 }
1315 
1316 /*
1317  * flush all members of flush->mc_list from device dev->mc_list
1318  */
1319 static void bond_mc_list_flush(struct net_device *bond_dev, struct net_device *slave_dev)
1320 {
1321 	struct bonding *bond = bond_dev->priv;
1322 	struct dev_mc_list *dmi;
1323 
1324 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
1325 		dev_mc_delete(slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1326 	}
1327 
1328 	if (bond->params.mode == BOND_MODE_8023AD) {
1329 		/* del lacpdu mc addr from mc list */
1330 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
1331 
1332 		dev_mc_delete(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
1333 	}
1334 }
1335 
1336 /*--------------------------- Active slave change ---------------------------*/
1337 
1338 /*
1339  * Update the mc list and multicast-related flags for the new and
1340  * old active slaves (if any) according to the multicast mode, and
1341  * promiscuous flags unconditionally.
1342  */
1343 static void bond_mc_swap(struct bonding *bond, struct slave *new_active, struct slave *old_active)
1344 {
1345 	struct dev_mc_list *dmi;
1346 
1347 	if (!USES_PRIMARY(bond->params.mode)) {
1348 		/* nothing to do -  mc list is already up-to-date on
1349 		 * all slaves
1350 		 */
1351 		return;
1352 	}
1353 
1354 	if (old_active) {
1355 		if (bond->dev->flags & IFF_PROMISC) {
1356 			dev_set_promiscuity(old_active->dev, -1);
1357 		}
1358 
1359 		if (bond->dev->flags & IFF_ALLMULTI) {
1360 			dev_set_allmulti(old_active->dev, -1);
1361 		}
1362 
1363 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
1364 			dev_mc_delete(old_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1365 		}
1366 	}
1367 
1368 	if (new_active) {
1369 		if (bond->dev->flags & IFF_PROMISC) {
1370 			dev_set_promiscuity(new_active->dev, 1);
1371 		}
1372 
1373 		if (bond->dev->flags & IFF_ALLMULTI) {
1374 			dev_set_allmulti(new_active->dev, 1);
1375 		}
1376 
1377 		for (dmi = bond->dev->mc_list; dmi; dmi = dmi->next) {
1378 			dev_mc_add(new_active->dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1379 		}
1380 	}
1381 }
1382 
1383 /**
1384  * find_best_interface - select the best available slave to be the active one
1385  * @bond: our bonding struct
1386  *
1387  * Warning: Caller must hold curr_slave_lock for writing.
1388  */
1389 static struct slave *bond_find_best_slave(struct bonding *bond)
1390 {
1391 	struct slave *new_active, *old_active;
1392 	struct slave *bestslave = NULL;
1393 	int mintime = bond->params.updelay;
1394 	int i;
1395 
1396 	new_active = old_active = bond->curr_active_slave;
1397 
1398 	if (!new_active) { /* there were no active slaves left */
1399 		if (bond->slave_cnt > 0) {  /* found one slave */
1400 			new_active = bond->first_slave;
1401 		} else {
1402 			return NULL; /* still no slave, return NULL */
1403 		}
1404 	}
1405 
1406 	/* first try the primary link; if arping, a link must tx/rx traffic
1407 	 * before it can be considered the curr_active_slave - also, we would skip
1408 	 * slaves between the curr_active_slave and primary_slave that may be up
1409 	 * and able to arp
1410 	 */
1411 	if ((bond->primary_slave) &&
1412 	    (!bond->params.arp_interval) &&
1413 	    (IS_UP(bond->primary_slave->dev))) {
1414 		new_active = bond->primary_slave;
1415 	}
1416 
1417 	/* remember where to stop iterating over the slaves */
1418 	old_active = new_active;
1419 
1420 	bond_for_each_slave_from(bond, new_active, i, old_active) {
1421 		if (IS_UP(new_active->dev)) {
1422 			if (new_active->link == BOND_LINK_UP) {
1423 				return new_active;
1424 			} else if (new_active->link == BOND_LINK_BACK) {
1425 				/* link up, but waiting for stabilization */
1426 				if (new_active->delay < mintime) {
1427 					mintime = new_active->delay;
1428 					bestslave = new_active;
1429 				}
1430 			}
1431 		}
1432 	}
1433 
1434 	return bestslave;
1435 }
1436 
1437 /**
1438  * change_active_interface - change the active slave into the specified one
1439  * @bond: our bonding struct
1440  * @new: the new slave to make the active one
1441  *
1442  * Set the new slave to the bond's settings and unset them on the old
1443  * curr_active_slave.
1444  * Setting include flags, mc-list, promiscuity, allmulti, etc.
1445  *
1446  * If @new's link state is %BOND_LINK_BACK we'll set it to %BOND_LINK_UP,
1447  * because it is apparently the best available slave we have, even though its
1448  * updelay hasn't timed out yet.
1449  *
1450  * Warning: Caller must hold curr_slave_lock for writing.
1451  */
1452 static void bond_change_active_slave(struct bonding *bond, struct slave *new_active)
1453 {
1454 	struct slave *old_active = bond->curr_active_slave;
1455 
1456 	if (old_active == new_active) {
1457 		return;
1458 	}
1459 
1460 	if (new_active) {
1461 		if (new_active->link == BOND_LINK_BACK) {
1462 			if (USES_PRIMARY(bond->params.mode)) {
1463 				printk(KERN_INFO DRV_NAME
1464 				       ": %s: making interface %s the new "
1465 				       "active one %d ms earlier.\n",
1466 				       bond->dev->name, new_active->dev->name,
1467 				       (bond->params.updelay - new_active->delay) * bond->params.miimon);
1468 			}
1469 
1470 			new_active->delay = 0;
1471 			new_active->link = BOND_LINK_UP;
1472 			new_active->jiffies = jiffies;
1473 
1474 			if (bond->params.mode == BOND_MODE_8023AD) {
1475 				bond_3ad_handle_link_change(new_active, BOND_LINK_UP);
1476 			}
1477 
1478 			if ((bond->params.mode == BOND_MODE_TLB) ||
1479 			    (bond->params.mode == BOND_MODE_ALB)) {
1480 				bond_alb_handle_link_change(bond, new_active, BOND_LINK_UP);
1481 			}
1482 		} else {
1483 			if (USES_PRIMARY(bond->params.mode)) {
1484 				printk(KERN_INFO DRV_NAME
1485 				       ": %s: making interface %s the new "
1486 				       "active one.\n",
1487 				       bond->dev->name, new_active->dev->name);
1488 			}
1489 		}
1490 	}
1491 
1492 	if (USES_PRIMARY(bond->params.mode)) {
1493 		bond_mc_swap(bond, new_active, old_active);
1494 	}
1495 
1496 	if ((bond->params.mode == BOND_MODE_TLB) ||
1497 	    (bond->params.mode == BOND_MODE_ALB)) {
1498 		bond_alb_handle_active_change(bond, new_active);
1499 	} else {
1500 		bond->curr_active_slave = new_active;
1501 	}
1502 
1503 	if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
1504 		if (old_active) {
1505 			bond_set_slave_inactive_flags(old_active);
1506 		}
1507 
1508 		if (new_active) {
1509 			bond_set_slave_active_flags(new_active);
1510 		}
1511 		bond_send_gratuitous_arp(bond);
1512 	}
1513 }
1514 
1515 /**
1516  * bond_select_active_slave - select a new active slave, if needed
1517  * @bond: our bonding struct
1518  *
1519  * This functions shoud be called when one of the following occurs:
1520  * - The old curr_active_slave has been released or lost its link.
1521  * - The primary_slave has got its link back.
1522  * - A slave has got its link back and there's no old curr_active_slave.
1523  *
1524  * Warning: Caller must hold curr_slave_lock for writing.
1525  */
1526 static void bond_select_active_slave(struct bonding *bond)
1527 {
1528 	struct slave *best_slave;
1529 
1530 	best_slave = bond_find_best_slave(bond);
1531 	if (best_slave != bond->curr_active_slave) {
1532 		bond_change_active_slave(bond, best_slave);
1533 	}
1534 }
1535 
1536 /*--------------------------- slave list handling ---------------------------*/
1537 
1538 /*
1539  * This function attaches the slave to the end of list.
1540  *
1541  * bond->lock held for writing by caller.
1542  */
1543 static void bond_attach_slave(struct bonding *bond, struct slave *new_slave)
1544 {
1545 	if (bond->first_slave == NULL) { /* attaching the first slave */
1546 		new_slave->next = new_slave;
1547 		new_slave->prev = new_slave;
1548 		bond->first_slave = new_slave;
1549 	} else {
1550 		new_slave->next = bond->first_slave;
1551 		new_slave->prev = bond->first_slave->prev;
1552 		new_slave->next->prev = new_slave;
1553 		new_slave->prev->next = new_slave;
1554 	}
1555 
1556 	bond->slave_cnt++;
1557 }
1558 
1559 /*
1560  * This function detaches the slave from the list.
1561  * WARNING: no check is made to verify if the slave effectively
1562  * belongs to <bond>.
1563  * Nothing is freed on return, structures are just unchained.
1564  * If any slave pointer in bond was pointing to <slave>,
1565  * it should be changed by the calling function.
1566  *
1567  * bond->lock held for writing by caller.
1568  */
1569 static void bond_detach_slave(struct bonding *bond, struct slave *slave)
1570 {
1571 	if (slave->next) {
1572 		slave->next->prev = slave->prev;
1573 	}
1574 
1575 	if (slave->prev) {
1576 		slave->prev->next = slave->next;
1577 	}
1578 
1579 	if (bond->first_slave == slave) { /* slave is the first slave */
1580 		if (bond->slave_cnt > 1) { /* there are more slave */
1581 			bond->first_slave = slave->next;
1582 		} else {
1583 			bond->first_slave = NULL; /* slave was the last one */
1584 		}
1585 	}
1586 
1587 	slave->next = NULL;
1588 	slave->prev = NULL;
1589 	bond->slave_cnt--;
1590 }
1591 
1592 /*---------------------------------- IOCTL ----------------------------------*/
1593 
1594 static int bond_sethwaddr(struct net_device *bond_dev, struct net_device *slave_dev)
1595 {
1596 	dprintk("bond_dev=%p\n", bond_dev);
1597 	dprintk("slave_dev=%p\n", slave_dev);
1598 	dprintk("slave_dev->addr_len=%d\n", slave_dev->addr_len);
1599 	memcpy(bond_dev->dev_addr, slave_dev->dev_addr, slave_dev->addr_len);
1600 	return 0;
1601 }
1602 
1603 #define BOND_INTERSECT_FEATURES \
1604 	(NETIF_F_SG|NETIF_F_IP_CSUM|NETIF_F_NO_CSUM|NETIF_F_HW_CSUM)
1605 
1606 /*
1607  * Compute the features available to the bonding device by
1608  * intersection of all of the slave devices' BOND_INTERSECT_FEATURES.
1609  * Call this after attaching or detaching a slave to update the
1610  * bond's features.
1611  */
1612 static int bond_compute_features(struct bonding *bond)
1613 {
1614 	int i;
1615 	struct slave *slave;
1616 	struct net_device *bond_dev = bond->dev;
1617 	int features = bond->bond_features;
1618 
1619 	bond_for_each_slave(bond, slave, i) {
1620 		struct net_device * slave_dev = slave->dev;
1621 		if (i == 0) {
1622 			features |= BOND_INTERSECT_FEATURES;
1623 		}
1624 		features &=
1625 			~(~slave_dev->features & BOND_INTERSECT_FEATURES);
1626 	}
1627 
1628 	/* turn off NETIF_F_SG if we need a csum and h/w can't do it */
1629 	if ((features & NETIF_F_SG) &&
1630 		!(features & (NETIF_F_IP_CSUM |
1631 			      NETIF_F_NO_CSUM |
1632 			      NETIF_F_HW_CSUM))) {
1633 		features &= ~NETIF_F_SG;
1634 	}
1635 
1636 	bond_dev->features = features;
1637 
1638 	return 0;
1639 }
1640 
1641 /* enslave device <slave> to bond device <master> */
1642 static int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
1643 {
1644 	struct bonding *bond = bond_dev->priv;
1645 	struct slave *new_slave = NULL;
1646 	struct dev_mc_list *dmi;
1647 	struct sockaddr addr;
1648 	int link_reporting;
1649 	int old_features = bond_dev->features;
1650 	int res = 0;
1651 
1652 	if (!bond->params.use_carrier && slave_dev->ethtool_ops == NULL &&
1653 		slave_dev->do_ioctl == NULL) {
1654 		printk(KERN_WARNING DRV_NAME
1655 		       ": Warning : no link monitoring support for %s\n",
1656 		       slave_dev->name);
1657 	}
1658 
1659 	/* bond must be initialized by bond_open() before enslaving */
1660 	if (!(bond_dev->flags & IFF_UP)) {
1661 		dprintk("Error, master_dev is not up\n");
1662 		return -EPERM;
1663 	}
1664 
1665 	/* already enslaved */
1666 	if (slave_dev->flags & IFF_SLAVE) {
1667 		dprintk("Error, Device was already enslaved\n");
1668 		return -EBUSY;
1669 	}
1670 
1671 	/* vlan challenged mutual exclusion */
1672 	/* no need to lock since we're protected by rtnl_lock */
1673 	if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {
1674 		dprintk("%s: NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1675 		if (!list_empty(&bond->vlan_list)) {
1676 			printk(KERN_ERR DRV_NAME
1677 			       ": Error: cannot enslave VLAN "
1678 			       "challenged slave %s on VLAN enabled "
1679 			       "bond %s\n", slave_dev->name,
1680 			       bond_dev->name);
1681 			return -EPERM;
1682 		} else {
1683 			printk(KERN_WARNING DRV_NAME
1684 			       ": Warning: enslaved VLAN challenged "
1685 			       "slave %s. Adding VLANs will be blocked as "
1686 			       "long as %s is part of bond %s\n",
1687 			       slave_dev->name, slave_dev->name,
1688 			       bond_dev->name);
1689 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
1690 		}
1691 	} else {
1692 		dprintk("%s: ! NETIF_F_VLAN_CHALLENGED\n", slave_dev->name);
1693 		if (bond->slave_cnt == 0) {
1694 			/* First slave, and it is not VLAN challenged,
1695 			 * so remove the block of adding VLANs over the bond.
1696 			 */
1697 			bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
1698 		}
1699 	}
1700 
1701 	/*
1702 	 * Old ifenslave binaries are no longer supported.  These can
1703 	 * be identified with moderate accurary by the state of the slave:
1704 	 * the current ifenslave will set the interface down prior to
1705 	 * enslaving it; the old ifenslave will not.
1706 	 */
1707 	if ((slave_dev->flags & IFF_UP)) {
1708 		printk(KERN_ERR DRV_NAME ": %s is up. "
1709 		       "This may be due to an out of date ifenslave.\n",
1710 		       slave_dev->name);
1711 		res = -EPERM;
1712 		goto err_undo_flags;
1713 	}
1714 
1715 	if (slave_dev->set_mac_address == NULL) {
1716 		printk(KERN_ERR DRV_NAME
1717 		       ": Error: The slave device you specified does "
1718 		       "not support setting the MAC address.\n");
1719 		printk(KERN_ERR
1720 		       "Your kernel likely does not support slave devices.\n");
1721 
1722 		res = -EOPNOTSUPP;
1723 		goto err_undo_flags;
1724 	}
1725 
1726 	new_slave = kmalloc(sizeof(struct slave), GFP_KERNEL);
1727 	if (!new_slave) {
1728 		res = -ENOMEM;
1729 		goto err_undo_flags;
1730 	}
1731 
1732 	memset(new_slave, 0, sizeof(struct slave));
1733 
1734 	/* save slave's original flags before calling
1735 	 * netdev_set_master and dev_open
1736 	 */
1737 	new_slave->original_flags = slave_dev->flags;
1738 
1739 	/*
1740 	 * Save slave's original ("permanent") mac address for modes
1741 	 * that need it, and for restoring it upon release, and then
1742 	 * set it to the master's address
1743 	 */
1744 	memcpy(new_slave->perm_hwaddr, slave_dev->dev_addr, ETH_ALEN);
1745 
1746 	/*
1747 	 * Set slave to master's mac address.  The application already
1748 	 * set the master's mac address to that of the first slave
1749 	 */
1750 	memcpy(addr.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
1751 	addr.sa_family = slave_dev->type;
1752 	res = dev_set_mac_address(slave_dev, &addr);
1753 	if (res) {
1754 		dprintk("Error %d calling set_mac_address\n", res);
1755 		goto err_free;
1756 	}
1757 
1758 	/* open the slave since the application closed it */
1759 	res = dev_open(slave_dev);
1760 	if (res) {
1761 		dprintk("Openning slave %s failed\n", slave_dev->name);
1762 		goto err_restore_mac;
1763 	}
1764 
1765 	res = netdev_set_master(slave_dev, bond_dev);
1766 	if (res) {
1767 		dprintk("Error %d calling netdev_set_master\n", res);
1768 		goto err_close;
1769 	}
1770 
1771 	new_slave->dev = slave_dev;
1772 
1773 	if ((bond->params.mode == BOND_MODE_TLB) ||
1774 	    (bond->params.mode == BOND_MODE_ALB)) {
1775 		/* bond_alb_init_slave() must be called before all other stages since
1776 		 * it might fail and we do not want to have to undo everything
1777 		 */
1778 		res = bond_alb_init_slave(bond, new_slave);
1779 		if (res) {
1780 			goto err_unset_master;
1781 		}
1782 	}
1783 
1784 	/* If the mode USES_PRIMARY, then the new slave gets the
1785 	 * master's promisc (and mc) settings only if it becomes the
1786 	 * curr_active_slave, and that is taken care of later when calling
1787 	 * bond_change_active()
1788 	 */
1789 	if (!USES_PRIMARY(bond->params.mode)) {
1790 		/* set promiscuity level to new slave */
1791 		if (bond_dev->flags & IFF_PROMISC) {
1792 			dev_set_promiscuity(slave_dev, 1);
1793 		}
1794 
1795 		/* set allmulti level to new slave */
1796 		if (bond_dev->flags & IFF_ALLMULTI) {
1797 			dev_set_allmulti(slave_dev, 1);
1798 		}
1799 
1800 		/* upload master's mc_list to new slave */
1801 		for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
1802 			dev_mc_add (slave_dev, dmi->dmi_addr, dmi->dmi_addrlen, 0);
1803 		}
1804 	}
1805 
1806 	if (bond->params.mode == BOND_MODE_8023AD) {
1807 		/* add lacpdu mc addr to mc list */
1808 		u8 lacpdu_multicast[ETH_ALEN] = MULTICAST_LACPDU_ADDR;
1809 
1810 		dev_mc_add(slave_dev, lacpdu_multicast, ETH_ALEN, 0);
1811 	}
1812 
1813 	bond_add_vlans_on_slave(bond, slave_dev);
1814 
1815 	write_lock_bh(&bond->lock);
1816 
1817 	bond_attach_slave(bond, new_slave);
1818 
1819 	new_slave->delay = 0;
1820 	new_slave->link_failure_count = 0;
1821 
1822 	bond_compute_features(bond);
1823 
1824 	if (bond->params.miimon && !bond->params.use_carrier) {
1825 		link_reporting = bond_check_dev_link(bond, slave_dev, 1);
1826 
1827 		if ((link_reporting == -1) && !bond->params.arp_interval) {
1828 			/*
1829 			 * miimon is set but a bonded network driver
1830 			 * does not support ETHTOOL/MII and
1831 			 * arp_interval is not set.  Note: if
1832 			 * use_carrier is enabled, we will never go
1833 			 * here (because netif_carrier is always
1834 			 * supported); thus, we don't need to change
1835 			 * the messages for netif_carrier.
1836 			 */
1837 			printk(KERN_WARNING DRV_NAME
1838 			       ": Warning: MII and ETHTOOL support not "
1839 			       "available for interface %s, and "
1840 			       "arp_interval/arp_ip_target module parameters "
1841 			       "not specified, thus bonding will not detect "
1842 			       "link failures! see bonding.txt for details.\n",
1843 			       slave_dev->name);
1844 		} else if (link_reporting == -1) {
1845 			/* unable get link status using mii/ethtool */
1846 			printk(KERN_WARNING DRV_NAME
1847 			       ": Warning: can't get link status from "
1848 			       "interface %s; the network driver associated "
1849 			       "with this interface does not support MII or "
1850 			       "ETHTOOL link status reporting, thus miimon "
1851 			       "has no effect on this interface.\n",
1852 			       slave_dev->name);
1853 		}
1854 	}
1855 
1856 	/* check for initial state */
1857 	if (!bond->params.miimon ||
1858 	    (bond_check_dev_link(bond, slave_dev, 0) == BMSR_LSTATUS)) {
1859 		if (bond->params.updelay) {
1860 			dprintk("Initial state of slave_dev is "
1861 				"BOND_LINK_BACK\n");
1862 			new_slave->link  = BOND_LINK_BACK;
1863 			new_slave->delay = bond->params.updelay;
1864 		} else {
1865 			dprintk("Initial state of slave_dev is "
1866 				"BOND_LINK_UP\n");
1867 			new_slave->link  = BOND_LINK_UP;
1868 		}
1869 		new_slave->jiffies = jiffies;
1870 	} else {
1871 		dprintk("Initial state of slave_dev is "
1872 			"BOND_LINK_DOWN\n");
1873 		new_slave->link  = BOND_LINK_DOWN;
1874 	}
1875 
1876 	if (bond_update_speed_duplex(new_slave) &&
1877 	    (new_slave->link != BOND_LINK_DOWN)) {
1878 		printk(KERN_WARNING DRV_NAME
1879 		       ": Warning: failed to get speed and duplex from %s, "
1880 		       "assumed to be 100Mb/sec and Full.\n",
1881 		       new_slave->dev->name);
1882 
1883 		if (bond->params.mode == BOND_MODE_8023AD) {
1884 			printk(KERN_WARNING
1885 			       "Operation of 802.3ad mode requires ETHTOOL "
1886 			       "support in base driver for proper aggregator "
1887 			       "selection.\n");
1888 		}
1889 	}
1890 
1891 	if (USES_PRIMARY(bond->params.mode) && bond->params.primary[0]) {
1892 		/* if there is a primary slave, remember it */
1893 		if (strcmp(bond->params.primary, new_slave->dev->name) == 0) {
1894 			bond->primary_slave = new_slave;
1895 		}
1896 	}
1897 
1898 	switch (bond->params.mode) {
1899 	case BOND_MODE_ACTIVEBACKUP:
1900 		/* if we're in active-backup mode, we need one and only one active
1901 		 * interface. The backup interfaces will have their NOARP flag set
1902 		 * because we need them to be completely deaf and not to respond to
1903 		 * any ARP request on the network to avoid fooling a switch. Thus,
1904 		 * since we guarantee that curr_active_slave always point to the last
1905 		 * usable interface, we just have to verify this interface's flag.
1906 		 */
1907 		if (((!bond->curr_active_slave) ||
1908 		     (bond->curr_active_slave->dev->flags & IFF_NOARP)) &&
1909 		    (new_slave->link != BOND_LINK_DOWN)) {
1910 			dprintk("This is the first active slave\n");
1911 			/* first slave or no active slave yet, and this link
1912 			   is OK, so make this interface the active one */
1913 			bond_change_active_slave(bond, new_slave);
1914 		} else {
1915 			dprintk("This is just a backup slave\n");
1916 			bond_set_slave_inactive_flags(new_slave);
1917 		}
1918 		break;
1919 	case BOND_MODE_8023AD:
1920 		/* in 802.3ad mode, the internal mechanism
1921 		 * will activate the slaves in the selected
1922 		 * aggregator
1923 		 */
1924 		bond_set_slave_inactive_flags(new_slave);
1925 		/* if this is the first slave */
1926 		if (bond->slave_cnt == 1) {
1927 			SLAVE_AD_INFO(new_slave).id = 1;
1928 			/* Initialize AD with the number of times that the AD timer is called in 1 second
1929 			 * can be called only after the mac address of the bond is set
1930 			 */
1931 			bond_3ad_initialize(bond, 1000/AD_TIMER_INTERVAL,
1932 					    bond->params.lacp_fast);
1933 		} else {
1934 			SLAVE_AD_INFO(new_slave).id =
1935 				SLAVE_AD_INFO(new_slave->prev).id + 1;
1936 		}
1937 
1938 		bond_3ad_bind_slave(new_slave);
1939 		break;
1940 	case BOND_MODE_TLB:
1941 	case BOND_MODE_ALB:
1942 		new_slave->state = BOND_STATE_ACTIVE;
1943 		if ((!bond->curr_active_slave) &&
1944 		    (new_slave->link != BOND_LINK_DOWN)) {
1945 			/* first slave or no active slave yet, and this link
1946 			 * is OK, so make this interface the active one
1947 			 */
1948 			bond_change_active_slave(bond, new_slave);
1949 		}
1950 		break;
1951 	default:
1952 		dprintk("This slave is always active in trunk mode\n");
1953 
1954 		/* always active in trunk mode */
1955 		new_slave->state = BOND_STATE_ACTIVE;
1956 
1957 		/* In trunking mode there is little meaning to curr_active_slave
1958 		 * anyway (it holds no special properties of the bond device),
1959 		 * so we can change it without calling change_active_interface()
1960 		 */
1961 		if (!bond->curr_active_slave) {
1962 			bond->curr_active_slave = new_slave;
1963 		}
1964 		break;
1965 	} /* switch(bond_mode) */
1966 
1967 	write_unlock_bh(&bond->lock);
1968 
1969 	printk(KERN_INFO DRV_NAME
1970 	       ": %s: enslaving %s as a%s interface with a%s link.\n",
1971 	       bond_dev->name, slave_dev->name,
1972 	       new_slave->state == BOND_STATE_ACTIVE ? "n active" : " backup",
1973 	       new_slave->link != BOND_LINK_DOWN ? "n up" : " down");
1974 
1975 	/* enslave is successful */
1976 	return 0;
1977 
1978 /* Undo stages on error */
1979 err_unset_master:
1980 	netdev_set_master(slave_dev, NULL);
1981 
1982 err_close:
1983 	dev_close(slave_dev);
1984 
1985 err_restore_mac:
1986 	memcpy(addr.sa_data, new_slave->perm_hwaddr, ETH_ALEN);
1987 	addr.sa_family = slave_dev->type;
1988 	dev_set_mac_address(slave_dev, &addr);
1989 
1990 err_free:
1991 	kfree(new_slave);
1992 
1993 err_undo_flags:
1994 	bond_dev->features = old_features;
1995 
1996 	return res;
1997 }
1998 
1999 /*
2000  * Try to release the slave device <slave> from the bond device <master>
2001  * It is legal to access curr_active_slave without a lock because all the function
2002  * is write-locked.
2003  *
2004  * The rules for slave state should be:
2005  *   for Active/Backup:
2006  *     Active stays on all backups go down
2007  *   for Bonded connections:
2008  *     The first up interface should be left on and all others downed.
2009  */
2010 static int bond_release(struct net_device *bond_dev, struct net_device *slave_dev)
2011 {
2012 	struct bonding *bond = bond_dev->priv;
2013 	struct slave *slave, *oldcurrent;
2014 	struct sockaddr addr;
2015 	int mac_addr_differ;
2016 
2017 	/* slave is not a slave or master is not master of this slave */
2018 	if (!(slave_dev->flags & IFF_SLAVE) ||
2019 	    (slave_dev->master != bond_dev)) {
2020 		printk(KERN_ERR DRV_NAME
2021 		       ": Error: %s: cannot release %s.\n",
2022 		       bond_dev->name, slave_dev->name);
2023 		return -EINVAL;
2024 	}
2025 
2026 	write_lock_bh(&bond->lock);
2027 
2028 	slave = bond_get_slave_by_dev(bond, slave_dev);
2029 	if (!slave) {
2030 		/* not a slave of this bond */
2031 		printk(KERN_INFO DRV_NAME
2032 		       ": %s: %s not enslaved\n",
2033 		       bond_dev->name, slave_dev->name);
2034 		return -EINVAL;
2035 	}
2036 
2037 	mac_addr_differ = memcmp(bond_dev->dev_addr,
2038 				 slave->perm_hwaddr,
2039 				 ETH_ALEN);
2040 	if (!mac_addr_differ && (bond->slave_cnt > 1)) {
2041 		printk(KERN_WARNING DRV_NAME
2042 		       ": Warning: the permanent HWaddr of %s "
2043 		       "- %02X:%02X:%02X:%02X:%02X:%02X - is "
2044 		       "still in use by %s. Set the HWaddr of "
2045 		       "%s to a different address to avoid "
2046 		       "conflicts.\n",
2047 		       slave_dev->name,
2048 		       slave->perm_hwaddr[0],
2049 		       slave->perm_hwaddr[1],
2050 		       slave->perm_hwaddr[2],
2051 		       slave->perm_hwaddr[3],
2052 		       slave->perm_hwaddr[4],
2053 		       slave->perm_hwaddr[5],
2054 		       bond_dev->name,
2055 		       slave_dev->name);
2056 	}
2057 
2058 	/* Inform AD package of unbinding of slave. */
2059 	if (bond->params.mode == BOND_MODE_8023AD) {
2060 		/* must be called before the slave is
2061 		 * detached from the list
2062 		 */
2063 		bond_3ad_unbind_slave(slave);
2064 	}
2065 
2066 	printk(KERN_INFO DRV_NAME
2067 	       ": %s: releasing %s interface %s\n",
2068 	       bond_dev->name,
2069 	       (slave->state == BOND_STATE_ACTIVE)
2070 	       ? "active" : "backup",
2071 	       slave_dev->name);
2072 
2073 	oldcurrent = bond->curr_active_slave;
2074 
2075 	bond->current_arp_slave = NULL;
2076 
2077 	/* release the slave from its bond */
2078 	bond_detach_slave(bond, slave);
2079 
2080 	bond_compute_features(bond);
2081 
2082 	if (bond->primary_slave == slave) {
2083 		bond->primary_slave = NULL;
2084 	}
2085 
2086 	if (oldcurrent == slave) {
2087 		bond_change_active_slave(bond, NULL);
2088 	}
2089 
2090 	if ((bond->params.mode == BOND_MODE_TLB) ||
2091 	    (bond->params.mode == BOND_MODE_ALB)) {
2092 		/* Must be called only after the slave has been
2093 		 * detached from the list and the curr_active_slave
2094 		 * has been cleared (if our_slave == old_current),
2095 		 * but before a new active slave is selected.
2096 		 */
2097 		bond_alb_deinit_slave(bond, slave);
2098 	}
2099 
2100 	if (oldcurrent == slave) {
2101 		bond_select_active_slave(bond);
2102 
2103 		if (!bond->curr_active_slave) {
2104 			printk(KERN_INFO DRV_NAME
2105 			       ": %s: now running without any active "
2106 			       "interface !\n",
2107 			       bond_dev->name);
2108 		}
2109 	}
2110 
2111 	if (bond->slave_cnt == 0) {
2112 		/* if the last slave was removed, zero the mac address
2113 		 * of the master so it will be set by the application
2114 		 * to the mac address of the first slave
2115 		 */
2116 		memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
2117 
2118 		if (list_empty(&bond->vlan_list)) {
2119 			bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
2120 		} else {
2121 			printk(KERN_WARNING DRV_NAME
2122 			       ": Warning: clearing HW address of %s while it "
2123 			       "still has VLANs.\n",
2124 			       bond_dev->name);
2125 			printk(KERN_WARNING DRV_NAME
2126 			       ": When re-adding slaves, make sure the bond's "
2127 			       "HW address matches its VLANs'.\n");
2128 		}
2129 	} else if ((bond_dev->features & NETIF_F_VLAN_CHALLENGED) &&
2130 		   !bond_has_challenged_slaves(bond)) {
2131 		printk(KERN_INFO DRV_NAME
2132 		       ": last VLAN challenged slave %s "
2133 		       "left bond %s. VLAN blocking is removed\n",
2134 		       slave_dev->name, bond_dev->name);
2135 		bond_dev->features &= ~NETIF_F_VLAN_CHALLENGED;
2136 	}
2137 
2138 	write_unlock_bh(&bond->lock);
2139 
2140 	bond_del_vlans_from_slave(bond, slave_dev);
2141 
2142 	/* If the mode USES_PRIMARY, then we should only remove its
2143 	 * promisc and mc settings if it was the curr_active_slave, but that was
2144 	 * already taken care of above when we detached the slave
2145 	 */
2146 	if (!USES_PRIMARY(bond->params.mode)) {
2147 		/* unset promiscuity level from slave */
2148 		if (bond_dev->flags & IFF_PROMISC) {
2149 			dev_set_promiscuity(slave_dev, -1);
2150 		}
2151 
2152 		/* unset allmulti level from slave */
2153 		if (bond_dev->flags & IFF_ALLMULTI) {
2154 			dev_set_allmulti(slave_dev, -1);
2155 		}
2156 
2157 		/* flush master's mc_list from slave */
2158 		bond_mc_list_flush(bond_dev, slave_dev);
2159 	}
2160 
2161 	netdev_set_master(slave_dev, NULL);
2162 
2163 	/* close slave before restoring its mac address */
2164 	dev_close(slave_dev);
2165 
2166 	/* restore original ("permanent") mac address */
2167 	memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
2168 	addr.sa_family = slave_dev->type;
2169 	dev_set_mac_address(slave_dev, &addr);
2170 
2171 	/* restore the original state of the
2172 	 * IFF_NOARP flag that might have been
2173 	 * set by bond_set_slave_inactive_flags()
2174 	 */
2175 	if ((slave->original_flags & IFF_NOARP) == 0) {
2176 		slave_dev->flags &= ~IFF_NOARP;
2177 	}
2178 
2179 	kfree(slave);
2180 
2181 	return 0;  /* deletion OK */
2182 }
2183 
2184 /*
2185  * This function releases all slaves.
2186  */
2187 static int bond_release_all(struct net_device *bond_dev)
2188 {
2189 	struct bonding *bond = bond_dev->priv;
2190 	struct slave *slave;
2191 	struct net_device *slave_dev;
2192 	struct sockaddr addr;
2193 
2194 	write_lock_bh(&bond->lock);
2195 
2196 	if (bond->slave_cnt == 0) {
2197 		goto out;
2198 	}
2199 
2200 	bond->current_arp_slave = NULL;
2201 	bond->primary_slave = NULL;
2202 	bond_change_active_slave(bond, NULL);
2203 
2204 	while ((slave = bond->first_slave) != NULL) {
2205 		/* Inform AD package of unbinding of slave
2206 		 * before slave is detached from the list.
2207 		 */
2208 		if (bond->params.mode == BOND_MODE_8023AD) {
2209 			bond_3ad_unbind_slave(slave);
2210 		}
2211 
2212 		slave_dev = slave->dev;
2213 		bond_detach_slave(bond, slave);
2214 
2215 		if ((bond->params.mode == BOND_MODE_TLB) ||
2216 		    (bond->params.mode == BOND_MODE_ALB)) {
2217 			/* must be called only after the slave
2218 			 * has been detached from the list
2219 			 */
2220 			bond_alb_deinit_slave(bond, slave);
2221 		}
2222 
2223 		bond_compute_features(bond);
2224 
2225 		/* now that the slave is detached, unlock and perform
2226 		 * all the undo steps that should not be called from
2227 		 * within a lock.
2228 		 */
2229 		write_unlock_bh(&bond->lock);
2230 
2231 		bond_del_vlans_from_slave(bond, slave_dev);
2232 
2233 		/* If the mode USES_PRIMARY, then we should only remove its
2234 		 * promisc and mc settings if it was the curr_active_slave, but that was
2235 		 * already taken care of above when we detached the slave
2236 		 */
2237 		if (!USES_PRIMARY(bond->params.mode)) {
2238 			/* unset promiscuity level from slave */
2239 			if (bond_dev->flags & IFF_PROMISC) {
2240 				dev_set_promiscuity(slave_dev, -1);
2241 			}
2242 
2243 			/* unset allmulti level from slave */
2244 			if (bond_dev->flags & IFF_ALLMULTI) {
2245 				dev_set_allmulti(slave_dev, -1);
2246 			}
2247 
2248 			/* flush master's mc_list from slave */
2249 			bond_mc_list_flush(bond_dev, slave_dev);
2250 		}
2251 
2252 		netdev_set_master(slave_dev, NULL);
2253 
2254 		/* close slave before restoring its mac address */
2255 		dev_close(slave_dev);
2256 
2257 		/* restore original ("permanent") mac address*/
2258 		memcpy(addr.sa_data, slave->perm_hwaddr, ETH_ALEN);
2259 		addr.sa_family = slave_dev->type;
2260 		dev_set_mac_address(slave_dev, &addr);
2261 
2262 		/* restore the original state of the IFF_NOARP flag that might have
2263 		 * been set by bond_set_slave_inactive_flags()
2264 		 */
2265 		if ((slave->original_flags & IFF_NOARP) == 0) {
2266 			slave_dev->flags &= ~IFF_NOARP;
2267 		}
2268 
2269 		kfree(slave);
2270 
2271 		/* re-acquire the lock before getting the next slave */
2272 		write_lock_bh(&bond->lock);
2273 	}
2274 
2275 	/* zero the mac address of the master so it will be
2276 	 * set by the application to the mac address of the
2277 	 * first slave
2278 	 */
2279 	memset(bond_dev->dev_addr, 0, bond_dev->addr_len);
2280 
2281 	if (list_empty(&bond->vlan_list)) {
2282 		bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
2283 	} else {
2284 		printk(KERN_WARNING DRV_NAME
2285 		       ": Warning: clearing HW address of %s while it "
2286 		       "still has VLANs.\n",
2287 		       bond_dev->name);
2288 		printk(KERN_WARNING DRV_NAME
2289 		       ": When re-adding slaves, make sure the bond's "
2290 		       "HW address matches its VLANs'.\n");
2291 	}
2292 
2293 	printk(KERN_INFO DRV_NAME
2294 	       ": %s: released all slaves\n",
2295 	       bond_dev->name);
2296 
2297 out:
2298 	write_unlock_bh(&bond->lock);
2299 
2300 	return 0;
2301 }
2302 
2303 /*
2304  * This function changes the active slave to slave <slave_dev>.
2305  * It returns -EINVAL in the following cases.
2306  *  - <slave_dev> is not found in the list.
2307  *  - There is not active slave now.
2308  *  - <slave_dev> is already active.
2309  *  - The link state of <slave_dev> is not BOND_LINK_UP.
2310  *  - <slave_dev> is not running.
2311  * In these cases, this fuction does nothing.
2312  * In the other cases, currnt_slave pointer is changed and 0 is returned.
2313  */
2314 static int bond_ioctl_change_active(struct net_device *bond_dev, struct net_device *slave_dev)
2315 {
2316 	struct bonding *bond = bond_dev->priv;
2317 	struct slave *old_active = NULL;
2318 	struct slave *new_active = NULL;
2319 	int res = 0;
2320 
2321 	if (!USES_PRIMARY(bond->params.mode)) {
2322 		return -EINVAL;
2323 	}
2324 
2325 	/* Verify that master_dev is indeed the master of slave_dev */
2326 	if (!(slave_dev->flags & IFF_SLAVE) ||
2327 	    (slave_dev->master != bond_dev)) {
2328 		return -EINVAL;
2329 	}
2330 
2331 	write_lock_bh(&bond->lock);
2332 
2333 	old_active = bond->curr_active_slave;
2334 	new_active = bond_get_slave_by_dev(bond, slave_dev);
2335 
2336 	/*
2337 	 * Changing to the current active: do nothing; return success.
2338 	 */
2339 	if (new_active && (new_active == old_active)) {
2340 		write_unlock_bh(&bond->lock);
2341 		return 0;
2342 	}
2343 
2344 	if ((new_active) &&
2345 	    (old_active) &&
2346 	    (new_active->link == BOND_LINK_UP) &&
2347 	    IS_UP(new_active->dev)) {
2348 		bond_change_active_slave(bond, new_active);
2349 	} else {
2350 		res = -EINVAL;
2351 	}
2352 
2353 	write_unlock_bh(&bond->lock);
2354 
2355 	return res;
2356 }
2357 
2358 static int bond_info_query(struct net_device *bond_dev, struct ifbond *info)
2359 {
2360 	struct bonding *bond = bond_dev->priv;
2361 
2362 	info->bond_mode = bond->params.mode;
2363 	info->miimon = bond->params.miimon;
2364 
2365 	read_lock_bh(&bond->lock);
2366 	info->num_slaves = bond->slave_cnt;
2367 	read_unlock_bh(&bond->lock);
2368 
2369 	return 0;
2370 }
2371 
2372 static int bond_slave_info_query(struct net_device *bond_dev, struct ifslave *info)
2373 {
2374 	struct bonding *bond = bond_dev->priv;
2375 	struct slave *slave;
2376 	int i, found = 0;
2377 
2378 	if (info->slave_id < 0) {
2379 		return -ENODEV;
2380 	}
2381 
2382 	read_lock_bh(&bond->lock);
2383 
2384 	bond_for_each_slave(bond, slave, i) {
2385 		if (i == (int)info->slave_id) {
2386 			found = 1;
2387 			break;
2388 		}
2389 	}
2390 
2391 	read_unlock_bh(&bond->lock);
2392 
2393 	if (found) {
2394 		strcpy(info->slave_name, slave->dev->name);
2395 		info->link = slave->link;
2396 		info->state = slave->state;
2397 		info->link_failure_count = slave->link_failure_count;
2398 	} else {
2399 		return -ENODEV;
2400 	}
2401 
2402 	return 0;
2403 }
2404 
2405 /*-------------------------------- Monitoring -------------------------------*/
2406 
2407 /* this function is called regularly to monitor each slave's link. */
2408 static void bond_mii_monitor(struct net_device *bond_dev)
2409 {
2410 	struct bonding *bond = bond_dev->priv;
2411 	struct slave *slave, *oldcurrent;
2412 	int do_failover = 0;
2413 	int delta_in_ticks;
2414 	int i;
2415 
2416 	read_lock(&bond->lock);
2417 
2418 	delta_in_ticks = (bond->params.miimon * HZ) / 1000;
2419 
2420 	if (bond->kill_timers) {
2421 		goto out;
2422 	}
2423 
2424 	if (bond->slave_cnt == 0) {
2425 		goto re_arm;
2426 	}
2427 
2428 	/* we will try to read the link status of each of our slaves, and
2429 	 * set their IFF_RUNNING flag appropriately. For each slave not
2430 	 * supporting MII status, we won't do anything so that a user-space
2431 	 * program could monitor the link itself if needed.
2432 	 */
2433 
2434 	read_lock(&bond->curr_slave_lock);
2435 	oldcurrent = bond->curr_active_slave;
2436 	read_unlock(&bond->curr_slave_lock);
2437 
2438 	bond_for_each_slave(bond, slave, i) {
2439 		struct net_device *slave_dev = slave->dev;
2440 		int link_state;
2441 		u16 old_speed = slave->speed;
2442 		u8 old_duplex = slave->duplex;
2443 
2444 		link_state = bond_check_dev_link(bond, slave_dev, 0);
2445 
2446 		switch (slave->link) {
2447 		case BOND_LINK_UP:	/* the link was up */
2448 			if (link_state == BMSR_LSTATUS) {
2449 				/* link stays up, nothing more to do */
2450 				break;
2451 			} else { /* link going down */
2452 				slave->link  = BOND_LINK_FAIL;
2453 				slave->delay = bond->params.downdelay;
2454 
2455 				if (slave->link_failure_count < UINT_MAX) {
2456 					slave->link_failure_count++;
2457 				}
2458 
2459 				if (bond->params.downdelay) {
2460 					printk(KERN_INFO DRV_NAME
2461 					       ": %s: link status down for %s "
2462 					       "interface %s, disabling it in "
2463 					       "%d ms.\n",
2464 					       bond_dev->name,
2465 					       IS_UP(slave_dev)
2466 					       ? ((bond->params.mode == BOND_MODE_ACTIVEBACKUP)
2467 						  ? ((slave == oldcurrent)
2468 						     ? "active " : "backup ")
2469 						  : "")
2470 					       : "idle ",
2471 					       slave_dev->name,
2472 					       bond->params.downdelay * bond->params.miimon);
2473 				}
2474 			}
2475 			/* no break ! fall through the BOND_LINK_FAIL test to
2476 			   ensure proper action to be taken
2477 			*/
2478 		case BOND_LINK_FAIL:	/* the link has just gone down */
2479 			if (link_state != BMSR_LSTATUS) {
2480 				/* link stays down */
2481 				if (slave->delay <= 0) {
2482 					/* link down for too long time */
2483 					slave->link = BOND_LINK_DOWN;
2484 
2485 					/* in active/backup mode, we must
2486 					 * completely disable this interface
2487 					 */
2488 					if ((bond->params.mode == BOND_MODE_ACTIVEBACKUP) ||
2489 					    (bond->params.mode == BOND_MODE_8023AD)) {
2490 						bond_set_slave_inactive_flags(slave);
2491 					}
2492 
2493 					printk(KERN_INFO DRV_NAME
2494 					       ": %s: link status definitely "
2495 					       "down for interface %s, "
2496 					       "disabling it\n",
2497 					       bond_dev->name,
2498 					       slave_dev->name);
2499 
2500 					/* notify ad that the link status has changed */
2501 					if (bond->params.mode == BOND_MODE_8023AD) {
2502 						bond_3ad_handle_link_change(slave, BOND_LINK_DOWN);
2503 					}
2504 
2505 					if ((bond->params.mode == BOND_MODE_TLB) ||
2506 					    (bond->params.mode == BOND_MODE_ALB)) {
2507 						bond_alb_handle_link_change(bond, slave, BOND_LINK_DOWN);
2508 					}
2509 
2510 					if (slave == oldcurrent) {
2511 						do_failover = 1;
2512 					}
2513 				} else {
2514 					slave->delay--;
2515 				}
2516 			} else {
2517 				/* link up again */
2518 				slave->link  = BOND_LINK_UP;
2519 				slave->jiffies = jiffies;
2520 				printk(KERN_INFO DRV_NAME
2521 				       ": %s: link status up again after %d "
2522 				       "ms for interface %s.\n",
2523 				       bond_dev->name,
2524 				       (bond->params.downdelay - slave->delay) * bond->params.miimon,
2525 				       slave_dev->name);
2526 			}
2527 			break;
2528 		case BOND_LINK_DOWN:	/* the link was down */
2529 			if (link_state != BMSR_LSTATUS) {
2530 				/* the link stays down, nothing more to do */
2531 				break;
2532 			} else {	/* link going up */
2533 				slave->link  = BOND_LINK_BACK;
2534 				slave->delay = bond->params.updelay;
2535 
2536 				if (bond->params.updelay) {
2537 					/* if updelay == 0, no need to
2538 					   advertise about a 0 ms delay */
2539 					printk(KERN_INFO DRV_NAME
2540 					       ": %s: link status up for "
2541 					       "interface %s, enabling it "
2542 					       "in %d ms.\n",
2543 					       bond_dev->name,
2544 					       slave_dev->name,
2545 					       bond->params.updelay * bond->params.miimon);
2546 				}
2547 			}
2548 			/* no break ! fall through the BOND_LINK_BACK state in
2549 			   case there's something to do.
2550 			*/
2551 		case BOND_LINK_BACK:	/* the link has just come back */
2552 			if (link_state != BMSR_LSTATUS) {
2553 				/* link down again */
2554 				slave->link  = BOND_LINK_DOWN;
2555 
2556 				printk(KERN_INFO DRV_NAME
2557 				       ": %s: link status down again after %d "
2558 				       "ms for interface %s.\n",
2559 				       bond_dev->name,
2560 				       (bond->params.updelay - slave->delay) * bond->params.miimon,
2561 				       slave_dev->name);
2562 			} else {
2563 				/* link stays up */
2564 				if (slave->delay == 0) {
2565 					/* now the link has been up for long time enough */
2566 					slave->link = BOND_LINK_UP;
2567 					slave->jiffies = jiffies;
2568 
2569 					if (bond->params.mode == BOND_MODE_8023AD) {
2570 						/* prevent it from being the active one */
2571 						slave->state = BOND_STATE_BACKUP;
2572 					} else if (bond->params.mode != BOND_MODE_ACTIVEBACKUP) {
2573 						/* make it immediately active */
2574 						slave->state = BOND_STATE_ACTIVE;
2575 					} else if (slave != bond->primary_slave) {
2576 						/* prevent it from being the active one */
2577 						slave->state = BOND_STATE_BACKUP;
2578 					}
2579 
2580 					printk(KERN_INFO DRV_NAME
2581 					       ": %s: link status definitely "
2582 					       "up for interface %s.\n",
2583 					       bond_dev->name,
2584 					       slave_dev->name);
2585 
2586 					/* notify ad that the link status has changed */
2587 					if (bond->params.mode == BOND_MODE_8023AD) {
2588 						bond_3ad_handle_link_change(slave, BOND_LINK_UP);
2589 					}
2590 
2591 					if ((bond->params.mode == BOND_MODE_TLB) ||
2592 					    (bond->params.mode == BOND_MODE_ALB)) {
2593 						bond_alb_handle_link_change(bond, slave, BOND_LINK_UP);
2594 					}
2595 
2596 					if ((!oldcurrent) ||
2597 					    (slave == bond->primary_slave)) {
2598 						do_failover = 1;
2599 					}
2600 				} else {
2601 					slave->delay--;
2602 				}
2603 			}
2604 			break;
2605 		default:
2606 			/* Should not happen */
2607 			printk(KERN_ERR "bonding: Error: %s  Illegal value (link=%d)\n",
2608 			       slave->dev->name, slave->link);
2609 			goto out;
2610 		} /* end of switch (slave->link) */
2611 
2612 		bond_update_speed_duplex(slave);
2613 
2614 		if (bond->params.mode == BOND_MODE_8023AD) {
2615 			if (old_speed != slave->speed) {
2616 				bond_3ad_adapter_speed_changed(slave);
2617 			}
2618 
2619 			if (old_duplex != slave->duplex) {
2620 				bond_3ad_adapter_duplex_changed(slave);
2621 			}
2622 		}
2623 
2624 	} /* end of for */
2625 
2626 	if (do_failover) {
2627 		write_lock(&bond->curr_slave_lock);
2628 
2629 		bond_select_active_slave(bond);
2630 
2631 		if (oldcurrent && !bond->curr_active_slave) {
2632 			printk(KERN_INFO DRV_NAME
2633 			       ": %s: now running without any active "
2634 			       "interface !\n",
2635 			       bond_dev->name);
2636 		}
2637 
2638 		write_unlock(&bond->curr_slave_lock);
2639 	}
2640 
2641 re_arm:
2642 	if (bond->params.miimon) {
2643 		mod_timer(&bond->mii_timer, jiffies + delta_in_ticks);
2644 	}
2645 out:
2646 	read_unlock(&bond->lock);
2647 }
2648 
2649 
2650 static u32 bond_glean_dev_ip(struct net_device *dev)
2651 {
2652 	struct in_device *idev;
2653 	struct in_ifaddr *ifa;
2654 	u32 addr = 0;
2655 
2656 	if (!dev)
2657 		return 0;
2658 
2659 	rcu_read_lock();
2660 	idev = __in_dev_get_rcu(dev);
2661 	if (!idev)
2662 		goto out;
2663 
2664 	ifa = idev->ifa_list;
2665 	if (!ifa)
2666 		goto out;
2667 
2668 	addr = ifa->ifa_local;
2669 out:
2670 	rcu_read_unlock();
2671 	return addr;
2672 }
2673 
2674 static int bond_has_ip(struct bonding *bond)
2675 {
2676 	struct vlan_entry *vlan, *vlan_next;
2677 
2678 	if (bond->master_ip)
2679 		return 1;
2680 
2681 	if (list_empty(&bond->vlan_list))
2682 		return 0;
2683 
2684 	list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2685 				 vlan_list) {
2686 		if (vlan->vlan_ip)
2687 			return 1;
2688 	}
2689 
2690 	return 0;
2691 }
2692 
2693 /*
2694  * We go to the (large) trouble of VLAN tagging ARP frames because
2695  * switches in VLAN mode (especially if ports are configured as
2696  * "native" to a VLAN) might not pass non-tagged frames.
2697  */
2698 static void bond_arp_send(struct net_device *slave_dev, int arp_op, u32 dest_ip, u32 src_ip, unsigned short vlan_id)
2699 {
2700 	struct sk_buff *skb;
2701 
2702 	dprintk("arp %d on slave %s: dst %x src %x vid %d\n", arp_op,
2703 	       slave_dev->name, dest_ip, src_ip, vlan_id);
2704 
2705 	skb = arp_create(arp_op, ETH_P_ARP, dest_ip, slave_dev, src_ip,
2706 			 NULL, slave_dev->dev_addr, NULL);
2707 
2708 	if (!skb) {
2709 		printk(KERN_ERR DRV_NAME ": ARP packet allocation failed\n");
2710 		return;
2711 	}
2712 	if (vlan_id) {
2713 		skb = vlan_put_tag(skb, vlan_id);
2714 		if (!skb) {
2715 			printk(KERN_ERR DRV_NAME ": failed to insert VLAN tag\n");
2716 			return;
2717 		}
2718 	}
2719 	arp_xmit(skb);
2720 }
2721 
2722 
2723 static void bond_arp_send_all(struct bonding *bond, struct slave *slave)
2724 {
2725 	int i, vlan_id, rv;
2726 	u32 *targets = bond->params.arp_targets;
2727 	struct vlan_entry *vlan, *vlan_next;
2728 	struct net_device *vlan_dev;
2729 	struct flowi fl;
2730 	struct rtable *rt;
2731 
2732 	for (i = 0; (i < BOND_MAX_ARP_TARGETS) && targets[i]; i++) {
2733 		dprintk("basa: target %x\n", targets[i]);
2734 		if (list_empty(&bond->vlan_list)) {
2735 			dprintk("basa: empty vlan: arp_send\n");
2736 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2737 				      bond->master_ip, 0);
2738 			continue;
2739 		}
2740 
2741 		/*
2742 		 * If VLANs are configured, we do a route lookup to
2743 		 * determine which VLAN interface would be used, so we
2744 		 * can tag the ARP with the proper VLAN tag.
2745 		 */
2746 		memset(&fl, 0, sizeof(fl));
2747 		fl.fl4_dst = targets[i];
2748 		fl.fl4_tos = RTO_ONLINK;
2749 
2750 		rv = ip_route_output_key(&rt, &fl);
2751 		if (rv) {
2752 			if (net_ratelimit()) {
2753 				printk(KERN_WARNING DRV_NAME
2754 			     ": %s: no route to arp_ip_target %u.%u.%u.%u\n",
2755 				       bond->dev->name, NIPQUAD(fl.fl4_dst));
2756 			}
2757 			continue;
2758 		}
2759 
2760 		/*
2761 		 * This target is not on a VLAN
2762 		 */
2763 		if (rt->u.dst.dev == bond->dev) {
2764 			ip_rt_put(rt);
2765 			dprintk("basa: rtdev == bond->dev: arp_send\n");
2766 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2767 				      bond->master_ip, 0);
2768 			continue;
2769 		}
2770 
2771 		vlan_id = 0;
2772 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
2773 					 vlan_list) {
2774 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2775 			if (vlan_dev == rt->u.dst.dev) {
2776 				vlan_id = vlan->vlan_id;
2777 				dprintk("basa: vlan match on %s %d\n",
2778 				       vlan_dev->name, vlan_id);
2779 				break;
2780 			}
2781 		}
2782 
2783 		if (vlan_id) {
2784 			ip_rt_put(rt);
2785 			bond_arp_send(slave->dev, ARPOP_REQUEST, targets[i],
2786 				      vlan->vlan_ip, vlan_id);
2787 			continue;
2788 		}
2789 
2790 		if (net_ratelimit()) {
2791 			printk(KERN_WARNING DRV_NAME
2792 	       ": %s: no path to arp_ip_target %u.%u.%u.%u via rt.dev %s\n",
2793 			       bond->dev->name, NIPQUAD(fl.fl4_dst),
2794 			       rt->u.dst.dev ? rt->u.dst.dev->name : "NULL");
2795 		}
2796 		ip_rt_put(rt);
2797 	}
2798 }
2799 
2800 /*
2801  * Kick out a gratuitous ARP for an IP on the bonding master plus one
2802  * for each VLAN above us.
2803  */
2804 static void bond_send_gratuitous_arp(struct bonding *bond)
2805 {
2806 	struct slave *slave = bond->curr_active_slave;
2807 	struct vlan_entry *vlan;
2808 	struct net_device *vlan_dev;
2809 
2810 	dprintk("bond_send_grat_arp: bond %s slave %s\n", bond->dev->name,
2811 				slave ? slave->dev->name : "NULL");
2812 	if (!slave)
2813 		return;
2814 
2815 	if (bond->master_ip) {
2816 		bond_arp_send(slave->dev, ARPOP_REPLY, bond->master_ip,
2817 				  bond->master_ip, 0);
2818 	}
2819 
2820 	list_for_each_entry(vlan, &bond->vlan_list, vlan_list) {
2821 		vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
2822 		if (vlan->vlan_ip) {
2823 			bond_arp_send(slave->dev, ARPOP_REPLY, vlan->vlan_ip,
2824 				      vlan->vlan_ip, vlan->vlan_id);
2825 		}
2826 	}
2827 }
2828 
2829 /*
2830  * this function is called regularly to monitor each slave's link
2831  * ensuring that traffic is being sent and received when arp monitoring
2832  * is used in load-balancing mode. if the adapter has been dormant, then an
2833  * arp is transmitted to generate traffic. see activebackup_arp_monitor for
2834  * arp monitoring in active backup mode.
2835  */
2836 static void bond_loadbalance_arp_mon(struct net_device *bond_dev)
2837 {
2838 	struct bonding *bond = bond_dev->priv;
2839 	struct slave *slave, *oldcurrent;
2840 	int do_failover = 0;
2841 	int delta_in_ticks;
2842 	int i;
2843 
2844 	read_lock(&bond->lock);
2845 
2846 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2847 
2848 	if (bond->kill_timers) {
2849 		goto out;
2850 	}
2851 
2852 	if (bond->slave_cnt == 0) {
2853 		goto re_arm;
2854 	}
2855 
2856 	read_lock(&bond->curr_slave_lock);
2857 	oldcurrent = bond->curr_active_slave;
2858 	read_unlock(&bond->curr_slave_lock);
2859 
2860 	/* see if any of the previous devices are up now (i.e. they have
2861 	 * xmt and rcv traffic). the curr_active_slave does not come into
2862 	 * the picture unless it is null. also, slave->jiffies is not needed
2863 	 * here because we send an arp on each slave and give a slave as
2864 	 * long as it needs to get the tx/rx within the delta.
2865 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2866 	 *       so it can wait
2867 	 */
2868 	bond_for_each_slave(bond, slave, i) {
2869 		if (slave->link != BOND_LINK_UP) {
2870 			if (((jiffies - slave->dev->trans_start) <= delta_in_ticks) &&
2871 			    ((jiffies - slave->dev->last_rx) <= delta_in_ticks)) {
2872 
2873 				slave->link  = BOND_LINK_UP;
2874 				slave->state = BOND_STATE_ACTIVE;
2875 
2876 				/* primary_slave has no meaning in round-robin
2877 				 * mode. the window of a slave being up and
2878 				 * curr_active_slave being null after enslaving
2879 				 * is closed.
2880 				 */
2881 				if (!oldcurrent) {
2882 					printk(KERN_INFO DRV_NAME
2883 					       ": %s: link status definitely "
2884 					       "up for interface %s, ",
2885 					       bond_dev->name,
2886 					       slave->dev->name);
2887 					do_failover = 1;
2888 				} else {
2889 					printk(KERN_INFO DRV_NAME
2890 					       ": %s: interface %s is now up\n",
2891 					       bond_dev->name,
2892 					       slave->dev->name);
2893 				}
2894 			}
2895 		} else {
2896 			/* slave->link == BOND_LINK_UP */
2897 
2898 			/* not all switches will respond to an arp request
2899 			 * when the source ip is 0, so don't take the link down
2900 			 * if we don't know our ip yet
2901 			 */
2902 			if (((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
2903 			    (((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
2904 			     bond_has_ip(bond))) {
2905 
2906 				slave->link  = BOND_LINK_DOWN;
2907 				slave->state = BOND_STATE_BACKUP;
2908 
2909 				if (slave->link_failure_count < UINT_MAX) {
2910 					slave->link_failure_count++;
2911 				}
2912 
2913 				printk(KERN_INFO DRV_NAME
2914 				       ": %s: interface %s is now down.\n",
2915 				       bond_dev->name,
2916 				       slave->dev->name);
2917 
2918 				if (slave == oldcurrent) {
2919 					do_failover = 1;
2920 				}
2921 			}
2922 		}
2923 
2924 		/* note: if switch is in round-robin mode, all links
2925 		 * must tx arp to ensure all links rx an arp - otherwise
2926 		 * links may oscillate or not come up at all; if switch is
2927 		 * in something like xor mode, there is nothing we can
2928 		 * do - all replies will be rx'ed on same link causing slaves
2929 		 * to be unstable during low/no traffic periods
2930 		 */
2931 		if (IS_UP(slave->dev)) {
2932 			bond_arp_send_all(bond, slave);
2933 		}
2934 	}
2935 
2936 	if (do_failover) {
2937 		write_lock(&bond->curr_slave_lock);
2938 
2939 		bond_select_active_slave(bond);
2940 
2941 		if (oldcurrent && !bond->curr_active_slave) {
2942 			printk(KERN_INFO DRV_NAME
2943 			       ": %s: now running without any active "
2944 			       "interface !\n",
2945 			       bond_dev->name);
2946 		}
2947 
2948 		write_unlock(&bond->curr_slave_lock);
2949 	}
2950 
2951 re_arm:
2952 	if (bond->params.arp_interval) {
2953 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
2954 	}
2955 out:
2956 	read_unlock(&bond->lock);
2957 }
2958 
2959 /*
2960  * When using arp monitoring in active-backup mode, this function is
2961  * called to determine if any backup slaves have went down or a new
2962  * current slave needs to be found.
2963  * The backup slaves never generate traffic, they are considered up by merely
2964  * receiving traffic. If the current slave goes down, each backup slave will
2965  * be given the opportunity to tx/rx an arp before being taken down - this
2966  * prevents all slaves from being taken down due to the current slave not
2967  * sending any traffic for the backups to receive. The arps are not necessarily
2968  * necessary, any tx and rx traffic will keep the current slave up. While any
2969  * rx traffic will keep the backup slaves up, the current slave is responsible
2970  * for generating traffic to keep them up regardless of any other traffic they
2971  * may have received.
2972  * see loadbalance_arp_monitor for arp monitoring in load balancing mode
2973  */
2974 static void bond_activebackup_arp_mon(struct net_device *bond_dev)
2975 {
2976 	struct bonding *bond = bond_dev->priv;
2977 	struct slave *slave;
2978 	int delta_in_ticks;
2979 	int i;
2980 
2981 	read_lock(&bond->lock);
2982 
2983 	delta_in_ticks = (bond->params.arp_interval * HZ) / 1000;
2984 
2985 	if (bond->kill_timers) {
2986 		goto out;
2987 	}
2988 
2989 	if (bond->slave_cnt == 0) {
2990 		goto re_arm;
2991 	}
2992 
2993 	/* determine if any slave has come up or any backup slave has
2994 	 * gone down
2995 	 * TODO: what about up/down delay in arp mode? it wasn't here before
2996 	 *       so it can wait
2997 	 */
2998 	bond_for_each_slave(bond, slave, i) {
2999 		if (slave->link != BOND_LINK_UP) {
3000 			if ((jiffies - slave->dev->last_rx) <= delta_in_ticks) {
3001 
3002 				slave->link = BOND_LINK_UP;
3003 
3004 				write_lock(&bond->curr_slave_lock);
3005 
3006 				if ((!bond->curr_active_slave) &&
3007 				    ((jiffies - slave->dev->trans_start) <= delta_in_ticks)) {
3008 					bond_change_active_slave(bond, slave);
3009 					bond->current_arp_slave = NULL;
3010 				} else if (bond->curr_active_slave != slave) {
3011 					/* this slave has just come up but we
3012 					 * already have a current slave; this
3013 					 * can also happen if bond_enslave adds
3014 					 * a new slave that is up while we are
3015 					 * searching for a new slave
3016 					 */
3017 					bond_set_slave_inactive_flags(slave);
3018 					bond->current_arp_slave = NULL;
3019 				}
3020 
3021 				if (slave == bond->curr_active_slave) {
3022 					printk(KERN_INFO DRV_NAME
3023 					       ": %s: %s is up and now the "
3024 					       "active interface\n",
3025 					       bond_dev->name,
3026 					       slave->dev->name);
3027 				} else {
3028 					printk(KERN_INFO DRV_NAME
3029 					       ": %s: backup interface %s is "
3030 					       "now up\n",
3031 					       bond_dev->name,
3032 					       slave->dev->name);
3033 				}
3034 
3035 				write_unlock(&bond->curr_slave_lock);
3036 			}
3037 		} else {
3038 			read_lock(&bond->curr_slave_lock);
3039 
3040 			if ((slave != bond->curr_active_slave) &&
3041 			    (!bond->current_arp_slave) &&
3042 			    (((jiffies - slave->dev->last_rx) >= 3*delta_in_ticks) &&
3043 			     bond_has_ip(bond))) {
3044 				/* a backup slave has gone down; three times
3045 				 * the delta allows the current slave to be
3046 				 * taken out before the backup slave.
3047 				 * note: a non-null current_arp_slave indicates
3048 				 * the curr_active_slave went down and we are
3049 				 * searching for a new one; under this
3050 				 * condition we only take the curr_active_slave
3051 				 * down - this gives each slave a chance to
3052 				 * tx/rx traffic before being taken out
3053 				 */
3054 
3055 				read_unlock(&bond->curr_slave_lock);
3056 
3057 				slave->link  = BOND_LINK_DOWN;
3058 
3059 				if (slave->link_failure_count < UINT_MAX) {
3060 					slave->link_failure_count++;
3061 				}
3062 
3063 				bond_set_slave_inactive_flags(slave);
3064 
3065 				printk(KERN_INFO DRV_NAME
3066 				       ": %s: backup interface %s is now down\n",
3067 				       bond_dev->name,
3068 				       slave->dev->name);
3069 			} else {
3070 				read_unlock(&bond->curr_slave_lock);
3071 			}
3072 		}
3073 	}
3074 
3075 	read_lock(&bond->curr_slave_lock);
3076 	slave = bond->curr_active_slave;
3077 	read_unlock(&bond->curr_slave_lock);
3078 
3079 	if (slave) {
3080 		/* if we have sent traffic in the past 2*arp_intervals but
3081 		 * haven't xmit and rx traffic in that time interval, select
3082 		 * a different slave. slave->jiffies is only updated when
3083 		 * a slave first becomes the curr_active_slave - not necessarily
3084 		 * after every arp; this ensures the slave has a full 2*delta
3085 		 * before being taken out. if a primary is being used, check
3086 		 * if it is up and needs to take over as the curr_active_slave
3087 		 */
3088 		if ((((jiffies - slave->dev->trans_start) >= (2*delta_in_ticks)) ||
3089 	    (((jiffies - slave->dev->last_rx) >= (2*delta_in_ticks)) &&
3090 	     bond_has_ip(bond))) &&
3091 		    ((jiffies - slave->jiffies) >= 2*delta_in_ticks)) {
3092 
3093 			slave->link  = BOND_LINK_DOWN;
3094 
3095 			if (slave->link_failure_count < UINT_MAX) {
3096 				slave->link_failure_count++;
3097 			}
3098 
3099 			printk(KERN_INFO DRV_NAME
3100 			       ": %s: link status down for active interface "
3101 			       "%s, disabling it\n",
3102 			       bond_dev->name,
3103 			       slave->dev->name);
3104 
3105 			write_lock(&bond->curr_slave_lock);
3106 
3107 			bond_select_active_slave(bond);
3108 			slave = bond->curr_active_slave;
3109 
3110 			write_unlock(&bond->curr_slave_lock);
3111 
3112 			bond->current_arp_slave = slave;
3113 
3114 			if (slave) {
3115 				slave->jiffies = jiffies;
3116 			}
3117 		} else if ((bond->primary_slave) &&
3118 			   (bond->primary_slave != slave) &&
3119 			   (bond->primary_slave->link == BOND_LINK_UP)) {
3120 			/* at this point, slave is the curr_active_slave */
3121 			printk(KERN_INFO DRV_NAME
3122 			       ": %s: changing from interface %s to primary "
3123 			       "interface %s\n",
3124 			       bond_dev->name,
3125 			       slave->dev->name,
3126 			       bond->primary_slave->dev->name);
3127 
3128 			/* primary is up so switch to it */
3129 			write_lock(&bond->curr_slave_lock);
3130 			bond_change_active_slave(bond, bond->primary_slave);
3131 			write_unlock(&bond->curr_slave_lock);
3132 
3133 			slave = bond->primary_slave;
3134 			slave->jiffies = jiffies;
3135 		} else {
3136 			bond->current_arp_slave = NULL;
3137 		}
3138 
3139 		/* the current slave must tx an arp to ensure backup slaves
3140 		 * rx traffic
3141 		 */
3142 		if (slave && bond_has_ip(bond)) {
3143 			bond_arp_send_all(bond, slave);
3144 		}
3145 	}
3146 
3147 	/* if we don't have a curr_active_slave, search for the next available
3148 	 * backup slave from the current_arp_slave and make it the candidate
3149 	 * for becoming the curr_active_slave
3150 	 */
3151 	if (!slave) {
3152 		if (!bond->current_arp_slave) {
3153 			bond->current_arp_slave = bond->first_slave;
3154 		}
3155 
3156 		if (bond->current_arp_slave) {
3157 			bond_set_slave_inactive_flags(bond->current_arp_slave);
3158 
3159 			/* search for next candidate */
3160 			bond_for_each_slave_from(bond, slave, i, bond->current_arp_slave->next) {
3161 				if (IS_UP(slave->dev)) {
3162 					slave->link = BOND_LINK_BACK;
3163 					bond_set_slave_active_flags(slave);
3164 					bond_arp_send_all(bond, slave);
3165 					slave->jiffies = jiffies;
3166 					bond->current_arp_slave = slave;
3167 					break;
3168 				}
3169 
3170 				/* if the link state is up at this point, we
3171 				 * mark it down - this can happen if we have
3172 				 * simultaneous link failures and
3173 				 * reselect_active_interface doesn't make this
3174 				 * one the current slave so it is still marked
3175 				 * up when it is actually down
3176 				 */
3177 				if (slave->link == BOND_LINK_UP) {
3178 					slave->link  = BOND_LINK_DOWN;
3179 					if (slave->link_failure_count < UINT_MAX) {
3180 						slave->link_failure_count++;
3181 					}
3182 
3183 					bond_set_slave_inactive_flags(slave);
3184 
3185 					printk(KERN_INFO DRV_NAME
3186 					       ": %s: backup interface %s is "
3187 					       "now down.\n",
3188 					       bond_dev->name,
3189 					       slave->dev->name);
3190 				}
3191 			}
3192 		}
3193 	}
3194 
3195 re_arm:
3196 	if (bond->params.arp_interval) {
3197 		mod_timer(&bond->arp_timer, jiffies + delta_in_ticks);
3198 	}
3199 out:
3200 	read_unlock(&bond->lock);
3201 }
3202 
3203 /*------------------------------ proc/seq_file-------------------------------*/
3204 
3205 #ifdef CONFIG_PROC_FS
3206 
3207 #define SEQ_START_TOKEN ((void *)1)
3208 
3209 static void *bond_info_seq_start(struct seq_file *seq, loff_t *pos)
3210 {
3211 	struct bonding *bond = seq->private;
3212 	loff_t off = 0;
3213 	struct slave *slave;
3214 	int i;
3215 
3216 	/* make sure the bond won't be taken away */
3217 	read_lock(&dev_base_lock);
3218 	read_lock_bh(&bond->lock);
3219 
3220 	if (*pos == 0) {
3221 		return SEQ_START_TOKEN;
3222 	}
3223 
3224 	bond_for_each_slave(bond, slave, i) {
3225 		if (++off == *pos) {
3226 			return slave;
3227 		}
3228 	}
3229 
3230 	return NULL;
3231 }
3232 
3233 static void *bond_info_seq_next(struct seq_file *seq, void *v, loff_t *pos)
3234 {
3235 	struct bonding *bond = seq->private;
3236 	struct slave *slave = v;
3237 
3238 	++*pos;
3239 	if (v == SEQ_START_TOKEN) {
3240 		return bond->first_slave;
3241 	}
3242 
3243 	slave = slave->next;
3244 
3245 	return (slave == bond->first_slave) ? NULL : slave;
3246 }
3247 
3248 static void bond_info_seq_stop(struct seq_file *seq, void *v)
3249 {
3250 	struct bonding *bond = seq->private;
3251 
3252 	read_unlock_bh(&bond->lock);
3253 	read_unlock(&dev_base_lock);
3254 }
3255 
3256 static void bond_info_show_master(struct seq_file *seq)
3257 {
3258 	struct bonding *bond = seq->private;
3259 	struct slave *curr;
3260 
3261 	read_lock(&bond->curr_slave_lock);
3262 	curr = bond->curr_active_slave;
3263 	read_unlock(&bond->curr_slave_lock);
3264 
3265 	seq_printf(seq, "Bonding Mode: %s\n",
3266 		   bond_mode_name(bond->params.mode));
3267 
3268 	if (USES_PRIMARY(bond->params.mode)) {
3269 		seq_printf(seq, "Primary Slave: %s\n",
3270 			   (bond->params.primary[0]) ?
3271 			   	bond->params.primary : "None");
3272 
3273 		seq_printf(seq, "Currently Active Slave: %s\n",
3274 			   (curr) ? curr->dev->name : "None");
3275 	}
3276 
3277 	seq_printf(seq, "MII Status: %s\n", (curr) ? "up" : "down");
3278 	seq_printf(seq, "MII Polling Interval (ms): %d\n", bond->params.miimon);
3279 	seq_printf(seq, "Up Delay (ms): %d\n",
3280 		   bond->params.updelay * bond->params.miimon);
3281 	seq_printf(seq, "Down Delay (ms): %d\n",
3282 		   bond->params.downdelay * bond->params.miimon);
3283 
3284 	if (bond->params.mode == BOND_MODE_8023AD) {
3285 		struct ad_info ad_info;
3286 
3287 		seq_puts(seq, "\n802.3ad info\n");
3288 		seq_printf(seq, "LACP rate: %s\n",
3289 			   (bond->params.lacp_fast) ? "fast" : "slow");
3290 
3291 		if (bond_3ad_get_active_agg_info(bond, &ad_info)) {
3292 			seq_printf(seq, "bond %s has no active aggregator\n",
3293 				   bond->dev->name);
3294 		} else {
3295 			seq_printf(seq, "Active Aggregator Info:\n");
3296 
3297 			seq_printf(seq, "\tAggregator ID: %d\n",
3298 				   ad_info.aggregator_id);
3299 			seq_printf(seq, "\tNumber of ports: %d\n",
3300 				   ad_info.ports);
3301 			seq_printf(seq, "\tActor Key: %d\n",
3302 				   ad_info.actor_key);
3303 			seq_printf(seq, "\tPartner Key: %d\n",
3304 				   ad_info.partner_key);
3305 			seq_printf(seq, "\tPartner Mac Address: %02x:%02x:%02x:%02x:%02x:%02x\n",
3306 				   ad_info.partner_system[0],
3307 				   ad_info.partner_system[1],
3308 				   ad_info.partner_system[2],
3309 				   ad_info.partner_system[3],
3310 				   ad_info.partner_system[4],
3311 				   ad_info.partner_system[5]);
3312 		}
3313 	}
3314 }
3315 
3316 static void bond_info_show_slave(struct seq_file *seq, const struct slave *slave)
3317 {
3318 	struct bonding *bond = seq->private;
3319 
3320 	seq_printf(seq, "\nSlave Interface: %s\n", slave->dev->name);
3321 	seq_printf(seq, "MII Status: %s\n",
3322 		   (slave->link == BOND_LINK_UP) ?  "up" : "down");
3323 	seq_printf(seq, "Link Failure Count: %d\n",
3324 		   slave->link_failure_count);
3325 
3326 	seq_printf(seq,
3327 		   "Permanent HW addr: %02x:%02x:%02x:%02x:%02x:%02x\n",
3328 		   slave->perm_hwaddr[0], slave->perm_hwaddr[1],
3329 		   slave->perm_hwaddr[2], slave->perm_hwaddr[3],
3330 		   slave->perm_hwaddr[4], slave->perm_hwaddr[5]);
3331 
3332 	if (bond->params.mode == BOND_MODE_8023AD) {
3333 		const struct aggregator *agg
3334 			= SLAVE_AD_INFO(slave).port.aggregator;
3335 
3336 		if (agg) {
3337 			seq_printf(seq, "Aggregator ID: %d\n",
3338 				   agg->aggregator_identifier);
3339 		} else {
3340 			seq_puts(seq, "Aggregator ID: N/A\n");
3341 		}
3342 	}
3343 }
3344 
3345 static int bond_info_seq_show(struct seq_file *seq, void *v)
3346 {
3347 	if (v == SEQ_START_TOKEN) {
3348 		seq_printf(seq, "%s\n", version);
3349 		bond_info_show_master(seq);
3350 	} else {
3351 		bond_info_show_slave(seq, v);
3352 	}
3353 
3354 	return 0;
3355 }
3356 
3357 static struct seq_operations bond_info_seq_ops = {
3358 	.start = bond_info_seq_start,
3359 	.next  = bond_info_seq_next,
3360 	.stop  = bond_info_seq_stop,
3361 	.show  = bond_info_seq_show,
3362 };
3363 
3364 static int bond_info_open(struct inode *inode, struct file *file)
3365 {
3366 	struct seq_file *seq;
3367 	struct proc_dir_entry *proc;
3368 	int res;
3369 
3370 	res = seq_open(file, &bond_info_seq_ops);
3371 	if (!res) {
3372 		/* recover the pointer buried in proc_dir_entry data */
3373 		seq = file->private_data;
3374 		proc = PDE(inode);
3375 		seq->private = proc->data;
3376 	}
3377 
3378 	return res;
3379 }
3380 
3381 static struct file_operations bond_info_fops = {
3382 	.owner   = THIS_MODULE,
3383 	.open    = bond_info_open,
3384 	.read    = seq_read,
3385 	.llseek  = seq_lseek,
3386 	.release = seq_release,
3387 };
3388 
3389 static int bond_create_proc_entry(struct bonding *bond)
3390 {
3391 	struct net_device *bond_dev = bond->dev;
3392 
3393 	if (bond_proc_dir) {
3394 		bond->proc_entry = create_proc_entry(bond_dev->name,
3395 						     S_IRUGO,
3396 						     bond_proc_dir);
3397 		if (bond->proc_entry == NULL) {
3398 			printk(KERN_WARNING DRV_NAME
3399 			       ": Warning: Cannot create /proc/net/%s/%s\n",
3400 			       DRV_NAME, bond_dev->name);
3401 		} else {
3402 			bond->proc_entry->data = bond;
3403 			bond->proc_entry->proc_fops = &bond_info_fops;
3404 			bond->proc_entry->owner = THIS_MODULE;
3405 			memcpy(bond->proc_file_name, bond_dev->name, IFNAMSIZ);
3406 		}
3407 	}
3408 
3409 	return 0;
3410 }
3411 
3412 static void bond_remove_proc_entry(struct bonding *bond)
3413 {
3414 	if (bond_proc_dir && bond->proc_entry) {
3415 		remove_proc_entry(bond->proc_file_name, bond_proc_dir);
3416 		memset(bond->proc_file_name, 0, IFNAMSIZ);
3417 		bond->proc_entry = NULL;
3418 	}
3419 }
3420 
3421 /* Create the bonding directory under /proc/net, if doesn't exist yet.
3422  * Caller must hold rtnl_lock.
3423  */
3424 static void bond_create_proc_dir(void)
3425 {
3426 	int len = strlen(DRV_NAME);
3427 
3428 	for (bond_proc_dir = proc_net->subdir; bond_proc_dir;
3429 	     bond_proc_dir = bond_proc_dir->next) {
3430 		if ((bond_proc_dir->namelen == len) &&
3431 		    !memcmp(bond_proc_dir->name, DRV_NAME, len)) {
3432 			break;
3433 		}
3434 	}
3435 
3436 	if (!bond_proc_dir) {
3437 		bond_proc_dir = proc_mkdir(DRV_NAME, proc_net);
3438 		if (bond_proc_dir) {
3439 			bond_proc_dir->owner = THIS_MODULE;
3440 		} else {
3441 			printk(KERN_WARNING DRV_NAME
3442 				": Warning: cannot create /proc/net/%s\n",
3443 				DRV_NAME);
3444 		}
3445 	}
3446 }
3447 
3448 /* Destroy the bonding directory under /proc/net, if empty.
3449  * Caller must hold rtnl_lock.
3450  */
3451 static void bond_destroy_proc_dir(void)
3452 {
3453 	struct proc_dir_entry *de;
3454 
3455 	if (!bond_proc_dir) {
3456 		return;
3457 	}
3458 
3459 	/* verify that the /proc dir is empty */
3460 	for (de = bond_proc_dir->subdir; de; de = de->next) {
3461 		/* ignore . and .. */
3462 		if (*(de->name) != '.') {
3463 			break;
3464 		}
3465 	}
3466 
3467 	if (de) {
3468 		if (bond_proc_dir->owner == THIS_MODULE) {
3469 			bond_proc_dir->owner = NULL;
3470 		}
3471 	} else {
3472 		remove_proc_entry(DRV_NAME, proc_net);
3473 		bond_proc_dir = NULL;
3474 	}
3475 }
3476 #endif /* CONFIG_PROC_FS */
3477 
3478 /*-------------------------- netdev event handling --------------------------*/
3479 
3480 /*
3481  * Change device name
3482  */
3483 static int bond_event_changename(struct bonding *bond)
3484 {
3485 #ifdef CONFIG_PROC_FS
3486 	bond_remove_proc_entry(bond);
3487 	bond_create_proc_entry(bond);
3488 #endif
3489 
3490 	return NOTIFY_DONE;
3491 }
3492 
3493 static int bond_master_netdev_event(unsigned long event, struct net_device *bond_dev)
3494 {
3495 	struct bonding *event_bond = bond_dev->priv;
3496 
3497 	switch (event) {
3498 	case NETDEV_CHANGENAME:
3499 		return bond_event_changename(event_bond);
3500 	case NETDEV_UNREGISTER:
3501 		/*
3502 		 * TODO: remove a bond from the list?
3503 		 */
3504 		break;
3505 	default:
3506 		break;
3507 	}
3508 
3509 	return NOTIFY_DONE;
3510 }
3511 
3512 static int bond_slave_netdev_event(unsigned long event, struct net_device *slave_dev)
3513 {
3514 	struct net_device *bond_dev = slave_dev->master;
3515 	struct bonding *bond = bond_dev->priv;
3516 
3517 	switch (event) {
3518 	case NETDEV_UNREGISTER:
3519 		if (bond_dev) {
3520 			bond_release(bond_dev, slave_dev);
3521 		}
3522 		break;
3523 	case NETDEV_CHANGE:
3524 		/*
3525 		 * TODO: is this what we get if somebody
3526 		 * sets up a hierarchical bond, then rmmod's
3527 		 * one of the slave bonding devices?
3528 		 */
3529 		break;
3530 	case NETDEV_DOWN:
3531 		/*
3532 		 * ... Or is it this?
3533 		 */
3534 		break;
3535 	case NETDEV_CHANGEMTU:
3536 		/*
3537 		 * TODO: Should slaves be allowed to
3538 		 * independently alter their MTU?  For
3539 		 * an active-backup bond, slaves need
3540 		 * not be the same type of device, so
3541 		 * MTUs may vary.  For other modes,
3542 		 * slaves arguably should have the
3543 		 * same MTUs. To do this, we'd need to
3544 		 * take over the slave's change_mtu
3545 		 * function for the duration of their
3546 		 * servitude.
3547 		 */
3548 		break;
3549 	case NETDEV_CHANGENAME:
3550 		/*
3551 		 * TODO: handle changing the primary's name
3552 		 */
3553 		break;
3554 	case NETDEV_FEAT_CHANGE:
3555 		bond_compute_features(bond);
3556 		break;
3557 	default:
3558 		break;
3559 	}
3560 
3561 	return NOTIFY_DONE;
3562 }
3563 
3564 /*
3565  * bond_netdev_event: handle netdev notifier chain events.
3566  *
3567  * This function receives events for the netdev chain.  The caller (an
3568  * ioctl handler calling notifier_call_chain) holds the necessary
3569  * locks for us to safely manipulate the slave devices (RTNL lock,
3570  * dev_probe_lock).
3571  */
3572 static int bond_netdev_event(struct notifier_block *this, unsigned long event, void *ptr)
3573 {
3574 	struct net_device *event_dev = (struct net_device *)ptr;
3575 
3576 	dprintk("event_dev: %s, event: %lx\n",
3577 		(event_dev ? event_dev->name : "None"),
3578 		event);
3579 
3580 	if (event_dev->flags & IFF_MASTER) {
3581 		dprintk("IFF_MASTER\n");
3582 		return bond_master_netdev_event(event, event_dev);
3583 	}
3584 
3585 	if (event_dev->flags & IFF_SLAVE) {
3586 		dprintk("IFF_SLAVE\n");
3587 		return bond_slave_netdev_event(event, event_dev);
3588 	}
3589 
3590 	return NOTIFY_DONE;
3591 }
3592 
3593 /*
3594  * bond_inetaddr_event: handle inetaddr notifier chain events.
3595  *
3596  * We keep track of device IPs primarily to use as source addresses in
3597  * ARP monitor probes (rather than spewing out broadcasts all the time).
3598  *
3599  * We track one IP for the main device (if it has one), plus one per VLAN.
3600  */
3601 static int bond_inetaddr_event(struct notifier_block *this, unsigned long event, void *ptr)
3602 {
3603 	struct in_ifaddr *ifa = ptr;
3604 	struct net_device *vlan_dev, *event_dev = ifa->ifa_dev->dev;
3605 	struct bonding *bond, *bond_next;
3606 	struct vlan_entry *vlan, *vlan_next;
3607 
3608 	list_for_each_entry_safe(bond, bond_next, &bond_dev_list, bond_list) {
3609 		if (bond->dev == event_dev) {
3610 			switch (event) {
3611 			case NETDEV_UP:
3612 				bond->master_ip = ifa->ifa_local;
3613 				return NOTIFY_OK;
3614 			case NETDEV_DOWN:
3615 				bond->master_ip = bond_glean_dev_ip(bond->dev);
3616 				return NOTIFY_OK;
3617 			default:
3618 				return NOTIFY_DONE;
3619 			}
3620 		}
3621 
3622 		if (list_empty(&bond->vlan_list))
3623 			continue;
3624 
3625 		list_for_each_entry_safe(vlan, vlan_next, &bond->vlan_list,
3626 					 vlan_list) {
3627 			vlan_dev = bond->vlgrp->vlan_devices[vlan->vlan_id];
3628 			if (vlan_dev == event_dev) {
3629 				switch (event) {
3630 				case NETDEV_UP:
3631 					vlan->vlan_ip = ifa->ifa_local;
3632 					return NOTIFY_OK;
3633 				case NETDEV_DOWN:
3634 					vlan->vlan_ip =
3635 						bond_glean_dev_ip(vlan_dev);
3636 					return NOTIFY_OK;
3637 				default:
3638 					return NOTIFY_DONE;
3639 				}
3640 			}
3641 		}
3642 	}
3643 	return NOTIFY_DONE;
3644 }
3645 
3646 static struct notifier_block bond_netdev_notifier = {
3647 	.notifier_call = bond_netdev_event,
3648 };
3649 
3650 static struct notifier_block bond_inetaddr_notifier = {
3651 	.notifier_call = bond_inetaddr_event,
3652 };
3653 
3654 /*-------------------------- Packet type handling ---------------------------*/
3655 
3656 /* register to receive lacpdus on a bond */
3657 static void bond_register_lacpdu(struct bonding *bond)
3658 {
3659 	struct packet_type *pk_type = &(BOND_AD_INFO(bond).ad_pkt_type);
3660 
3661 	/* initialize packet type */
3662 	pk_type->type = PKT_TYPE_LACPDU;
3663 	pk_type->dev = bond->dev;
3664 	pk_type->func = bond_3ad_lacpdu_recv;
3665 
3666 	dev_add_pack(pk_type);
3667 }
3668 
3669 /* unregister to receive lacpdus on a bond */
3670 static void bond_unregister_lacpdu(struct bonding *bond)
3671 {
3672 	dev_remove_pack(&(BOND_AD_INFO(bond).ad_pkt_type));
3673 }
3674 
3675 /*---------------------------- Hashing Policies -----------------------------*/
3676 
3677 /*
3678  * Hash for the the output device based upon layer 3 and layer 4 data. If
3679  * the packet is a frag or not TCP or UDP, just use layer 3 data.  If it is
3680  * altogether not IP, mimic bond_xmit_hash_policy_l2()
3681  */
3682 static int bond_xmit_hash_policy_l34(struct sk_buff *skb,
3683 				    struct net_device *bond_dev, int count)
3684 {
3685 	struct ethhdr *data = (struct ethhdr *)skb->data;
3686 	struct iphdr *iph = skb->nh.iph;
3687 	u16 *layer4hdr = (u16 *)((u32 *)iph + iph->ihl);
3688 	int layer4_xor = 0;
3689 
3690 	if (skb->protocol == __constant_htons(ETH_P_IP)) {
3691 		if (!(iph->frag_off & __constant_htons(IP_MF|IP_OFFSET)) &&
3692 		    (iph->protocol == IPPROTO_TCP ||
3693 		     iph->protocol == IPPROTO_UDP)) {
3694 			layer4_xor = htons((*layer4hdr ^ *(layer4hdr + 1)));
3695 		}
3696 		return (layer4_xor ^
3697 			((ntohl(iph->saddr ^ iph->daddr)) & 0xffff)) % count;
3698 
3699 	}
3700 
3701 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3702 }
3703 
3704 /*
3705  * Hash for the output device based upon layer 2 data
3706  */
3707 static int bond_xmit_hash_policy_l2(struct sk_buff *skb,
3708 				   struct net_device *bond_dev, int count)
3709 {
3710 	struct ethhdr *data = (struct ethhdr *)skb->data;
3711 
3712 	return (data->h_dest[5] ^ bond_dev->dev_addr[5]) % count;
3713 }
3714 
3715 /*-------------------------- Device entry points ----------------------------*/
3716 
3717 static int bond_open(struct net_device *bond_dev)
3718 {
3719 	struct bonding *bond = bond_dev->priv;
3720 	struct timer_list *mii_timer = &bond->mii_timer;
3721 	struct timer_list *arp_timer = &bond->arp_timer;
3722 
3723 	bond->kill_timers = 0;
3724 
3725 	if ((bond->params.mode == BOND_MODE_TLB) ||
3726 	    (bond->params.mode == BOND_MODE_ALB)) {
3727 		struct timer_list *alb_timer = &(BOND_ALB_INFO(bond).alb_timer);
3728 
3729 		/* bond_alb_initialize must be called before the timer
3730 		 * is started.
3731 		 */
3732 		if (bond_alb_initialize(bond, (bond->params.mode == BOND_MODE_ALB))) {
3733 			/* something went wrong - fail the open operation */
3734 			return -1;
3735 		}
3736 
3737 		init_timer(alb_timer);
3738 		alb_timer->expires  = jiffies + 1;
3739 		alb_timer->data     = (unsigned long)bond;
3740 		alb_timer->function = (void *)&bond_alb_monitor;
3741 		add_timer(alb_timer);
3742 	}
3743 
3744 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3745 		init_timer(mii_timer);
3746 		mii_timer->expires  = jiffies + 1;
3747 		mii_timer->data     = (unsigned long)bond_dev;
3748 		mii_timer->function = (void *)&bond_mii_monitor;
3749 		add_timer(mii_timer);
3750 	}
3751 
3752 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3753 		init_timer(arp_timer);
3754 		arp_timer->expires  = jiffies + 1;
3755 		arp_timer->data     = (unsigned long)bond_dev;
3756 		if (bond->params.mode == BOND_MODE_ACTIVEBACKUP) {
3757 			arp_timer->function = (void *)&bond_activebackup_arp_mon;
3758 		} else {
3759 			arp_timer->function = (void *)&bond_loadbalance_arp_mon;
3760 		}
3761 		add_timer(arp_timer);
3762 	}
3763 
3764 	if (bond->params.mode == BOND_MODE_8023AD) {
3765 		struct timer_list *ad_timer = &(BOND_AD_INFO(bond).ad_timer);
3766 		init_timer(ad_timer);
3767 		ad_timer->expires  = jiffies + 1;
3768 		ad_timer->data     = (unsigned long)bond;
3769 		ad_timer->function = (void *)&bond_3ad_state_machine_handler;
3770 		add_timer(ad_timer);
3771 
3772 		/* register to receive LACPDUs */
3773 		bond_register_lacpdu(bond);
3774 	}
3775 
3776 	return 0;
3777 }
3778 
3779 static int bond_close(struct net_device *bond_dev)
3780 {
3781 	struct bonding *bond = bond_dev->priv;
3782 
3783 	if (bond->params.mode == BOND_MODE_8023AD) {
3784 		/* Unregister the receive of LACPDUs */
3785 		bond_unregister_lacpdu(bond);
3786 	}
3787 
3788 	write_lock_bh(&bond->lock);
3789 
3790 	bond_mc_list_destroy(bond);
3791 
3792 	/* signal timers not to re-arm */
3793 	bond->kill_timers = 1;
3794 
3795 	write_unlock_bh(&bond->lock);
3796 
3797 	/* del_timer_sync must run without holding the bond->lock
3798 	 * because a running timer might be trying to hold it too
3799 	 */
3800 
3801 	if (bond->params.miimon) {  /* link check interval, in milliseconds. */
3802 		del_timer_sync(&bond->mii_timer);
3803 	}
3804 
3805 	if (bond->params.arp_interval) {  /* arp interval, in milliseconds. */
3806 		del_timer_sync(&bond->arp_timer);
3807 	}
3808 
3809 	switch (bond->params.mode) {
3810 	case BOND_MODE_8023AD:
3811 		del_timer_sync(&(BOND_AD_INFO(bond).ad_timer));
3812 		break;
3813 	case BOND_MODE_TLB:
3814 	case BOND_MODE_ALB:
3815 		del_timer_sync(&(BOND_ALB_INFO(bond).alb_timer));
3816 		break;
3817 	default:
3818 		break;
3819 	}
3820 
3821 	/* Release the bonded slaves */
3822 	bond_release_all(bond_dev);
3823 
3824 	if ((bond->params.mode == BOND_MODE_TLB) ||
3825 	    (bond->params.mode == BOND_MODE_ALB)) {
3826 		/* Must be called only after all
3827 		 * slaves have been released
3828 		 */
3829 		bond_alb_deinitialize(bond);
3830 	}
3831 
3832 	return 0;
3833 }
3834 
3835 static struct net_device_stats *bond_get_stats(struct net_device *bond_dev)
3836 {
3837 	struct bonding *bond = bond_dev->priv;
3838 	struct net_device_stats *stats = &(bond->stats), *sstats;
3839 	struct slave *slave;
3840 	int i;
3841 
3842 	memset(stats, 0, sizeof(struct net_device_stats));
3843 
3844 	read_lock_bh(&bond->lock);
3845 
3846 	bond_for_each_slave(bond, slave, i) {
3847 		sstats = slave->dev->get_stats(slave->dev);
3848 
3849 		stats->rx_packets += sstats->rx_packets;
3850 		stats->rx_bytes += sstats->rx_bytes;
3851 		stats->rx_errors += sstats->rx_errors;
3852 		stats->rx_dropped += sstats->rx_dropped;
3853 
3854 		stats->tx_packets += sstats->tx_packets;
3855 		stats->tx_bytes += sstats->tx_bytes;
3856 		stats->tx_errors += sstats->tx_errors;
3857 		stats->tx_dropped += sstats->tx_dropped;
3858 
3859 		stats->multicast += sstats->multicast;
3860 		stats->collisions += sstats->collisions;
3861 
3862 		stats->rx_length_errors += sstats->rx_length_errors;
3863 		stats->rx_over_errors += sstats->rx_over_errors;
3864 		stats->rx_crc_errors += sstats->rx_crc_errors;
3865 		stats->rx_frame_errors += sstats->rx_frame_errors;
3866 		stats->rx_fifo_errors += sstats->rx_fifo_errors;
3867 		stats->rx_missed_errors += sstats->rx_missed_errors;
3868 
3869 		stats->tx_aborted_errors += sstats->tx_aborted_errors;
3870 		stats->tx_carrier_errors += sstats->tx_carrier_errors;
3871 		stats->tx_fifo_errors += sstats->tx_fifo_errors;
3872 		stats->tx_heartbeat_errors += sstats->tx_heartbeat_errors;
3873 		stats->tx_window_errors += sstats->tx_window_errors;
3874 	}
3875 
3876 	read_unlock_bh(&bond->lock);
3877 
3878 	return stats;
3879 }
3880 
3881 static int bond_do_ioctl(struct net_device *bond_dev, struct ifreq *ifr, int cmd)
3882 {
3883 	struct net_device *slave_dev = NULL;
3884 	struct ifbond k_binfo;
3885 	struct ifbond __user *u_binfo = NULL;
3886 	struct ifslave k_sinfo;
3887 	struct ifslave __user *u_sinfo = NULL;
3888 	struct mii_ioctl_data *mii = NULL;
3889 	int res = 0;
3890 
3891 	dprintk("bond_ioctl: master=%s, cmd=%d\n",
3892 		bond_dev->name, cmd);
3893 
3894 	switch (cmd) {
3895 	case SIOCGMIIPHY:
3896 		mii = if_mii(ifr);
3897 		if (!mii) {
3898 			return -EINVAL;
3899 		}
3900 		mii->phy_id = 0;
3901 		/* Fall Through */
3902 	case SIOCGMIIREG:
3903 		/*
3904 		 * We do this again just in case we were called by SIOCGMIIREG
3905 		 * instead of SIOCGMIIPHY.
3906 		 */
3907 		mii = if_mii(ifr);
3908 		if (!mii) {
3909 			return -EINVAL;
3910 		}
3911 
3912 		if (mii->reg_num == 1) {
3913 			struct bonding *bond = bond_dev->priv;
3914 			mii->val_out = 0;
3915 			read_lock_bh(&bond->lock);
3916 			read_lock(&bond->curr_slave_lock);
3917 			if (bond->curr_active_slave) {
3918 				mii->val_out = BMSR_LSTATUS;
3919 			}
3920 			read_unlock(&bond->curr_slave_lock);
3921 			read_unlock_bh(&bond->lock);
3922 		}
3923 
3924 		return 0;
3925 	case BOND_INFO_QUERY_OLD:
3926 	case SIOCBONDINFOQUERY:
3927 		u_binfo = (struct ifbond __user *)ifr->ifr_data;
3928 
3929 		if (copy_from_user(&k_binfo, u_binfo, sizeof(ifbond))) {
3930 			return -EFAULT;
3931 		}
3932 
3933 		res = bond_info_query(bond_dev, &k_binfo);
3934 		if (res == 0) {
3935 			if (copy_to_user(u_binfo, &k_binfo, sizeof(ifbond))) {
3936 				return -EFAULT;
3937 			}
3938 		}
3939 
3940 		return res;
3941 	case BOND_SLAVE_INFO_QUERY_OLD:
3942 	case SIOCBONDSLAVEINFOQUERY:
3943 		u_sinfo = (struct ifslave __user *)ifr->ifr_data;
3944 
3945 		if (copy_from_user(&k_sinfo, u_sinfo, sizeof(ifslave))) {
3946 			return -EFAULT;
3947 		}
3948 
3949 		res = bond_slave_info_query(bond_dev, &k_sinfo);
3950 		if (res == 0) {
3951 			if (copy_to_user(u_sinfo, &k_sinfo, sizeof(ifslave))) {
3952 				return -EFAULT;
3953 			}
3954 		}
3955 
3956 		return res;
3957 	default:
3958 		/* Go on */
3959 		break;
3960 	}
3961 
3962 	if (!capable(CAP_NET_ADMIN)) {
3963 		return -EPERM;
3964 	}
3965 
3966 	slave_dev = dev_get_by_name(ifr->ifr_slave);
3967 
3968 	dprintk("slave_dev=%p: \n", slave_dev);
3969 
3970 	if (!slave_dev) {
3971 		res = -ENODEV;
3972 	} else {
3973 		dprintk("slave_dev->name=%s: \n", slave_dev->name);
3974 		switch (cmd) {
3975 		case BOND_ENSLAVE_OLD:
3976 		case SIOCBONDENSLAVE:
3977 			res = bond_enslave(bond_dev, slave_dev);
3978 			break;
3979 		case BOND_RELEASE_OLD:
3980 		case SIOCBONDRELEASE:
3981 			res = bond_release(bond_dev, slave_dev);
3982 			break;
3983 		case BOND_SETHWADDR_OLD:
3984 		case SIOCBONDSETHWADDR:
3985 			res = bond_sethwaddr(bond_dev, slave_dev);
3986 			break;
3987 		case BOND_CHANGE_ACTIVE_OLD:
3988 		case SIOCBONDCHANGEACTIVE:
3989 			res = bond_ioctl_change_active(bond_dev, slave_dev);
3990 			break;
3991 		default:
3992 			res = -EOPNOTSUPP;
3993 		}
3994 
3995 		dev_put(slave_dev);
3996 	}
3997 
3998 	return res;
3999 }
4000 
4001 static void bond_set_multicast_list(struct net_device *bond_dev)
4002 {
4003 	struct bonding *bond = bond_dev->priv;
4004 	struct dev_mc_list *dmi;
4005 
4006 	write_lock_bh(&bond->lock);
4007 
4008 	/*
4009 	 * Do promisc before checking multicast_mode
4010 	 */
4011 	if ((bond_dev->flags & IFF_PROMISC) && !(bond->flags & IFF_PROMISC)) {
4012 		bond_set_promiscuity(bond, 1);
4013 	}
4014 
4015 	if (!(bond_dev->flags & IFF_PROMISC) && (bond->flags & IFF_PROMISC)) {
4016 		bond_set_promiscuity(bond, -1);
4017 	}
4018 
4019 	/* set allmulti flag to slaves */
4020 	if ((bond_dev->flags & IFF_ALLMULTI) && !(bond->flags & IFF_ALLMULTI)) {
4021 		bond_set_allmulti(bond, 1);
4022 	}
4023 
4024 	if (!(bond_dev->flags & IFF_ALLMULTI) && (bond->flags & IFF_ALLMULTI)) {
4025 		bond_set_allmulti(bond, -1);
4026 	}
4027 
4028 	bond->flags = bond_dev->flags;
4029 
4030 	/* looking for addresses to add to slaves' mc list */
4031 	for (dmi = bond_dev->mc_list; dmi; dmi = dmi->next) {
4032 		if (!bond_mc_list_find_dmi(dmi, bond->mc_list)) {
4033 			bond_mc_add(bond, dmi->dmi_addr, dmi->dmi_addrlen);
4034 		}
4035 	}
4036 
4037 	/* looking for addresses to delete from slaves' list */
4038 	for (dmi = bond->mc_list; dmi; dmi = dmi->next) {
4039 		if (!bond_mc_list_find_dmi(dmi, bond_dev->mc_list)) {
4040 			bond_mc_delete(bond, dmi->dmi_addr, dmi->dmi_addrlen);
4041 		}
4042 	}
4043 
4044 	/* save master's multicast list */
4045 	bond_mc_list_destroy(bond);
4046 	bond_mc_list_copy(bond_dev->mc_list, bond, GFP_ATOMIC);
4047 
4048 	write_unlock_bh(&bond->lock);
4049 }
4050 
4051 /*
4052  * Change the MTU of all of a master's slaves to match the master
4053  */
4054 static int bond_change_mtu(struct net_device *bond_dev, int new_mtu)
4055 {
4056 	struct bonding *bond = bond_dev->priv;
4057 	struct slave *slave, *stop_at;
4058 	int res = 0;
4059 	int i;
4060 
4061 	dprintk("bond=%p, name=%s, new_mtu=%d\n", bond,
4062 		(bond_dev ? bond_dev->name : "None"), new_mtu);
4063 
4064 	/* Can't hold bond->lock with bh disabled here since
4065 	 * some base drivers panic. On the other hand we can't
4066 	 * hold bond->lock without bh disabled because we'll
4067 	 * deadlock. The only solution is to rely on the fact
4068 	 * that we're under rtnl_lock here, and the slaves
4069 	 * list won't change. This doesn't solve the problem
4070 	 * of setting the slave's MTU while it is
4071 	 * transmitting, but the assumption is that the base
4072 	 * driver can handle that.
4073 	 *
4074 	 * TODO: figure out a way to safely iterate the slaves
4075 	 * list, but without holding a lock around the actual
4076 	 * call to the base driver.
4077 	 */
4078 
4079 	bond_for_each_slave(bond, slave, i) {
4080 		dprintk("s %p s->p %p c_m %p\n", slave,
4081 			slave->prev, slave->dev->change_mtu);
4082 		res = dev_set_mtu(slave->dev, new_mtu);
4083 
4084 		if (res) {
4085 			/* If we failed to set the slave's mtu to the new value
4086 			 * we must abort the operation even in ACTIVE_BACKUP
4087 			 * mode, because if we allow the backup slaves to have
4088 			 * different mtu values than the active slave we'll
4089 			 * need to change their mtu when doing a failover. That
4090 			 * means changing their mtu from timer context, which
4091 			 * is probably not a good idea.
4092 			 */
4093 			dprintk("err %d %s\n", res, slave->dev->name);
4094 			goto unwind;
4095 		}
4096 	}
4097 
4098 	bond_dev->mtu = new_mtu;
4099 
4100 	return 0;
4101 
4102 unwind:
4103 	/* unwind from head to the slave that failed */
4104 	stop_at = slave;
4105 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
4106 		int tmp_res;
4107 
4108 		tmp_res = dev_set_mtu(slave->dev, bond_dev->mtu);
4109 		if (tmp_res) {
4110 			dprintk("unwind err %d dev %s\n", tmp_res,
4111 				slave->dev->name);
4112 		}
4113 	}
4114 
4115 	return res;
4116 }
4117 
4118 /*
4119  * Change HW address
4120  *
4121  * Note that many devices must be down to change the HW address, and
4122  * downing the master releases all slaves.  We can make bonds full of
4123  * bonding devices to test this, however.
4124  */
4125 static int bond_set_mac_address(struct net_device *bond_dev, void *addr)
4126 {
4127 	struct bonding *bond = bond_dev->priv;
4128 	struct sockaddr *sa = addr, tmp_sa;
4129 	struct slave *slave, *stop_at;
4130 	int res = 0;
4131 	int i;
4132 
4133 	dprintk("bond=%p, name=%s\n", bond, (bond_dev ? bond_dev->name : "None"));
4134 
4135 	if (!is_valid_ether_addr(sa->sa_data)) {
4136 		return -EADDRNOTAVAIL;
4137 	}
4138 
4139 	/* Can't hold bond->lock with bh disabled here since
4140 	 * some base drivers panic. On the other hand we can't
4141 	 * hold bond->lock without bh disabled because we'll
4142 	 * deadlock. The only solution is to rely on the fact
4143 	 * that we're under rtnl_lock here, and the slaves
4144 	 * list won't change. This doesn't solve the problem
4145 	 * of setting the slave's hw address while it is
4146 	 * transmitting, but the assumption is that the base
4147 	 * driver can handle that.
4148 	 *
4149 	 * TODO: figure out a way to safely iterate the slaves
4150 	 * list, but without holding a lock around the actual
4151 	 * call to the base driver.
4152 	 */
4153 
4154 	bond_for_each_slave(bond, slave, i) {
4155 		dprintk("slave %p %s\n", slave, slave->dev->name);
4156 
4157 		if (slave->dev->set_mac_address == NULL) {
4158 			res = -EOPNOTSUPP;
4159 			dprintk("EOPNOTSUPP %s\n", slave->dev->name);
4160 			goto unwind;
4161 		}
4162 
4163 		res = dev_set_mac_address(slave->dev, addr);
4164 		if (res) {
4165 			/* TODO: consider downing the slave
4166 			 * and retry ?
4167 			 * User should expect communications
4168 			 * breakage anyway until ARP finish
4169 			 * updating, so...
4170 			 */
4171 			dprintk("err %d %s\n", res, slave->dev->name);
4172 			goto unwind;
4173 		}
4174 	}
4175 
4176 	/* success */
4177 	memcpy(bond_dev->dev_addr, sa->sa_data, bond_dev->addr_len);
4178 	return 0;
4179 
4180 unwind:
4181 	memcpy(tmp_sa.sa_data, bond_dev->dev_addr, bond_dev->addr_len);
4182 	tmp_sa.sa_family = bond_dev->type;
4183 
4184 	/* unwind from head to the slave that failed */
4185 	stop_at = slave;
4186 	bond_for_each_slave_from_to(bond, slave, i, bond->first_slave, stop_at) {
4187 		int tmp_res;
4188 
4189 		tmp_res = dev_set_mac_address(slave->dev, &tmp_sa);
4190 		if (tmp_res) {
4191 			dprintk("unwind err %d dev %s\n", tmp_res,
4192 				slave->dev->name);
4193 		}
4194 	}
4195 
4196 	return res;
4197 }
4198 
4199 static int bond_xmit_roundrobin(struct sk_buff *skb, struct net_device *bond_dev)
4200 {
4201 	struct bonding *bond = bond_dev->priv;
4202 	struct slave *slave, *start_at;
4203 	int i;
4204 	int res = 1;
4205 
4206 	read_lock(&bond->lock);
4207 
4208 	if (!BOND_IS_OK(bond)) {
4209 		goto out;
4210 	}
4211 
4212 	read_lock(&bond->curr_slave_lock);
4213 	slave = start_at = bond->curr_active_slave;
4214 	read_unlock(&bond->curr_slave_lock);
4215 
4216 	if (!slave) {
4217 		goto out;
4218 	}
4219 
4220 	bond_for_each_slave_from(bond, slave, i, start_at) {
4221 		if (IS_UP(slave->dev) &&
4222 		    (slave->link == BOND_LINK_UP) &&
4223 		    (slave->state == BOND_STATE_ACTIVE)) {
4224 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
4225 
4226 			write_lock(&bond->curr_slave_lock);
4227 			bond->curr_active_slave = slave->next;
4228 			write_unlock(&bond->curr_slave_lock);
4229 
4230 			break;
4231 		}
4232 	}
4233 
4234 
4235 out:
4236 	if (res) {
4237 		/* no suitable interface, frame not sent */
4238 		dev_kfree_skb(skb);
4239 	}
4240 	read_unlock(&bond->lock);
4241 	return 0;
4242 }
4243 
4244 /*
4245  * in active-backup mode, we know that bond->curr_active_slave is always valid if
4246  * the bond has a usable interface.
4247  */
4248 static int bond_xmit_activebackup(struct sk_buff *skb, struct net_device *bond_dev)
4249 {
4250 	struct bonding *bond = bond_dev->priv;
4251 	int res = 1;
4252 
4253 	read_lock(&bond->lock);
4254 	read_lock(&bond->curr_slave_lock);
4255 
4256 	if (!BOND_IS_OK(bond)) {
4257 		goto out;
4258 	}
4259 
4260 	if (bond->curr_active_slave) { /* one usable interface */
4261 		res = bond_dev_queue_xmit(bond, skb, bond->curr_active_slave->dev);
4262 	}
4263 
4264 out:
4265 	if (res) {
4266 		/* no suitable interface, frame not sent */
4267 		dev_kfree_skb(skb);
4268 	}
4269 	read_unlock(&bond->curr_slave_lock);
4270 	read_unlock(&bond->lock);
4271 	return 0;
4272 }
4273 
4274 /*
4275  * In bond_xmit_xor() , we determine the output device by using a pre-
4276  * determined xmit_hash_policy(), If the selected device is not enabled,
4277  * find the next active slave.
4278  */
4279 static int bond_xmit_xor(struct sk_buff *skb, struct net_device *bond_dev)
4280 {
4281 	struct bonding *bond = bond_dev->priv;
4282 	struct slave *slave, *start_at;
4283 	int slave_no;
4284 	int i;
4285 	int res = 1;
4286 
4287 	read_lock(&bond->lock);
4288 
4289 	if (!BOND_IS_OK(bond)) {
4290 		goto out;
4291 	}
4292 
4293 	slave_no = bond->xmit_hash_policy(skb, bond_dev, bond->slave_cnt);
4294 
4295 	bond_for_each_slave(bond, slave, i) {
4296 		slave_no--;
4297 		if (slave_no < 0) {
4298 			break;
4299 		}
4300 	}
4301 
4302 	start_at = slave;
4303 
4304 	bond_for_each_slave_from(bond, slave, i, start_at) {
4305 		if (IS_UP(slave->dev) &&
4306 		    (slave->link == BOND_LINK_UP) &&
4307 		    (slave->state == BOND_STATE_ACTIVE)) {
4308 			res = bond_dev_queue_xmit(bond, skb, slave->dev);
4309 			break;
4310 		}
4311 	}
4312 
4313 out:
4314 	if (res) {
4315 		/* no suitable interface, frame not sent */
4316 		dev_kfree_skb(skb);
4317 	}
4318 	read_unlock(&bond->lock);
4319 	return 0;
4320 }
4321 
4322 /*
4323  * in broadcast mode, we send everything to all usable interfaces.
4324  */
4325 static int bond_xmit_broadcast(struct sk_buff *skb, struct net_device *bond_dev)
4326 {
4327 	struct bonding *bond = bond_dev->priv;
4328 	struct slave *slave, *start_at;
4329 	struct net_device *tx_dev = NULL;
4330 	int i;
4331 	int res = 1;
4332 
4333 	read_lock(&bond->lock);
4334 
4335 	if (!BOND_IS_OK(bond)) {
4336 		goto out;
4337 	}
4338 
4339 	read_lock(&bond->curr_slave_lock);
4340 	start_at = bond->curr_active_slave;
4341 	read_unlock(&bond->curr_slave_lock);
4342 
4343 	if (!start_at) {
4344 		goto out;
4345 	}
4346 
4347 	bond_for_each_slave_from(bond, slave, i, start_at) {
4348 		if (IS_UP(slave->dev) &&
4349 		    (slave->link == BOND_LINK_UP) &&
4350 		    (slave->state == BOND_STATE_ACTIVE)) {
4351 			if (tx_dev) {
4352 				struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC);
4353 				if (!skb2) {
4354 					printk(KERN_ERR DRV_NAME
4355 					       ": Error: bond_xmit_broadcast(): "
4356 					       "skb_clone() failed\n");
4357 					continue;
4358 				}
4359 
4360 				res = bond_dev_queue_xmit(bond, skb2, tx_dev);
4361 				if (res) {
4362 					dev_kfree_skb(skb2);
4363 					continue;
4364 				}
4365 			}
4366 			tx_dev = slave->dev;
4367 		}
4368 	}
4369 
4370 	if (tx_dev) {
4371 		res = bond_dev_queue_xmit(bond, skb, tx_dev);
4372 	}
4373 
4374 out:
4375 	if (res) {
4376 		/* no suitable interface, frame not sent */
4377 		dev_kfree_skb(skb);
4378 	}
4379 	/* frame sent to all suitable interfaces */
4380 	read_unlock(&bond->lock);
4381 	return 0;
4382 }
4383 
4384 /*------------------------- Device initialization ---------------------------*/
4385 
4386 /*
4387  * set bond mode specific net device operations
4388  */
4389 static inline void bond_set_mode_ops(struct bonding *bond, int mode)
4390 {
4391 	struct net_device *bond_dev = bond->dev;
4392 
4393 	switch (mode) {
4394 	case BOND_MODE_ROUNDROBIN:
4395 		bond_dev->hard_start_xmit = bond_xmit_roundrobin;
4396 		break;
4397 	case BOND_MODE_ACTIVEBACKUP:
4398 		bond_dev->hard_start_xmit = bond_xmit_activebackup;
4399 		break;
4400 	case BOND_MODE_XOR:
4401 		bond_dev->hard_start_xmit = bond_xmit_xor;
4402 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4403 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4404 		else
4405 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4406 		break;
4407 	case BOND_MODE_BROADCAST:
4408 		bond_dev->hard_start_xmit = bond_xmit_broadcast;
4409 		break;
4410 	case BOND_MODE_8023AD:
4411 		bond_dev->hard_start_xmit = bond_3ad_xmit_xor;
4412 		if (bond->params.xmit_policy == BOND_XMIT_POLICY_LAYER34)
4413 			bond->xmit_hash_policy = bond_xmit_hash_policy_l34;
4414 		else
4415 			bond->xmit_hash_policy = bond_xmit_hash_policy_l2;
4416 		break;
4417 	case BOND_MODE_TLB:
4418 	case BOND_MODE_ALB:
4419 		bond_dev->hard_start_xmit = bond_alb_xmit;
4420 		bond_dev->set_mac_address = bond_alb_set_mac_address;
4421 		break;
4422 	default:
4423 		/* Should never happen, mode already checked */
4424 		printk(KERN_ERR DRV_NAME
4425 		       ": Error: Unknown bonding mode %d\n",
4426 		       mode);
4427 		break;
4428 	}
4429 }
4430 
4431 static void bond_ethtool_get_drvinfo(struct net_device *bond_dev,
4432 				    struct ethtool_drvinfo *drvinfo)
4433 {
4434 	strncpy(drvinfo->driver, DRV_NAME, 32);
4435 	strncpy(drvinfo->version, DRV_VERSION, 32);
4436 	snprintf(drvinfo->fw_version, 32, "%d", BOND_ABI_VERSION);
4437 }
4438 
4439 static struct ethtool_ops bond_ethtool_ops = {
4440 	.get_tx_csum		= ethtool_op_get_tx_csum,
4441 	.get_sg			= ethtool_op_get_sg,
4442 	.get_drvinfo		= bond_ethtool_get_drvinfo,
4443 };
4444 
4445 /*
4446  * Does not allocate but creates a /proc entry.
4447  * Allowed to fail.
4448  */
4449 static int __init bond_init(struct net_device *bond_dev, struct bond_params *params)
4450 {
4451 	struct bonding *bond = bond_dev->priv;
4452 
4453 	dprintk("Begin bond_init for %s\n", bond_dev->name);
4454 
4455 	/* initialize rwlocks */
4456 	rwlock_init(&bond->lock);
4457 	rwlock_init(&bond->curr_slave_lock);
4458 
4459 	bond->params = *params; /* copy params struct */
4460 
4461 	/* Initialize pointers */
4462 	bond->first_slave = NULL;
4463 	bond->curr_active_slave = NULL;
4464 	bond->current_arp_slave = NULL;
4465 	bond->primary_slave = NULL;
4466 	bond->dev = bond_dev;
4467 	INIT_LIST_HEAD(&bond->vlan_list);
4468 
4469 	/* Initialize the device entry points */
4470 	bond_dev->open = bond_open;
4471 	bond_dev->stop = bond_close;
4472 	bond_dev->get_stats = bond_get_stats;
4473 	bond_dev->do_ioctl = bond_do_ioctl;
4474 	bond_dev->ethtool_ops = &bond_ethtool_ops;
4475 	bond_dev->set_multicast_list = bond_set_multicast_list;
4476 	bond_dev->change_mtu = bond_change_mtu;
4477 	bond_dev->set_mac_address = bond_set_mac_address;
4478 
4479 	bond_set_mode_ops(bond, bond->params.mode);
4480 
4481 	bond_dev->destructor = free_netdev;
4482 
4483 	/* Initialize the device options */
4484 	bond_dev->tx_queue_len = 0;
4485 	bond_dev->flags |= IFF_MASTER|IFF_MULTICAST;
4486 
4487 	/* At first, we block adding VLANs. That's the only way to
4488 	 * prevent problems that occur when adding VLANs over an
4489 	 * empty bond. The block will be removed once non-challenged
4490 	 * slaves are enslaved.
4491 	 */
4492 	bond_dev->features |= NETIF_F_VLAN_CHALLENGED;
4493 
4494 	/* don't acquire bond device's xmit_lock when
4495 	 * transmitting */
4496 	bond_dev->features |= NETIF_F_LLTX;
4497 
4498 	/* By default, we declare the bond to be fully
4499 	 * VLAN hardware accelerated capable. Special
4500 	 * care is taken in the various xmit functions
4501 	 * when there are slaves that are not hw accel
4502 	 * capable
4503 	 */
4504 	bond_dev->vlan_rx_register = bond_vlan_rx_register;
4505 	bond_dev->vlan_rx_add_vid  = bond_vlan_rx_add_vid;
4506 	bond_dev->vlan_rx_kill_vid = bond_vlan_rx_kill_vid;
4507 	bond_dev->features |= (NETIF_F_HW_VLAN_TX |
4508 			       NETIF_F_HW_VLAN_RX |
4509 			       NETIF_F_HW_VLAN_FILTER);
4510 
4511 	bond->bond_features = bond_dev->features;
4512 
4513 #ifdef CONFIG_PROC_FS
4514 	bond_create_proc_entry(bond);
4515 #endif
4516 
4517 	list_add_tail(&bond->bond_list, &bond_dev_list);
4518 
4519 	return 0;
4520 }
4521 
4522 /* De-initialize device specific data.
4523  * Caller must hold rtnl_lock.
4524  */
4525 static inline void bond_deinit(struct net_device *bond_dev)
4526 {
4527 	struct bonding *bond = bond_dev->priv;
4528 
4529 	list_del(&bond->bond_list);
4530 
4531 #ifdef CONFIG_PROC_FS
4532 	bond_remove_proc_entry(bond);
4533 #endif
4534 }
4535 
4536 /* Unregister and free all bond devices.
4537  * Caller must hold rtnl_lock.
4538  */
4539 static void bond_free_all(void)
4540 {
4541 	struct bonding *bond, *nxt;
4542 
4543 	list_for_each_entry_safe(bond, nxt, &bond_dev_list, bond_list) {
4544 		struct net_device *bond_dev = bond->dev;
4545 
4546 		unregister_netdevice(bond_dev);
4547 		bond_deinit(bond_dev);
4548 	}
4549 
4550 #ifdef CONFIG_PROC_FS
4551 	bond_destroy_proc_dir();
4552 #endif
4553 }
4554 
4555 /*------------------------- Module initialization ---------------------------*/
4556 
4557 /*
4558  * Convert string input module parms.  Accept either the
4559  * number of the mode or its string name.
4560  */
4561 static inline int bond_parse_parm(char *mode_arg, struct bond_parm_tbl *tbl)
4562 {
4563 	int i;
4564 
4565 	for (i = 0; tbl[i].modename; i++) {
4566 		if ((isdigit(*mode_arg) &&
4567 		     tbl[i].mode == simple_strtol(mode_arg, NULL, 0)) ||
4568 		    (strncmp(mode_arg, tbl[i].modename,
4569 			     strlen(tbl[i].modename)) == 0)) {
4570 			return tbl[i].mode;
4571 		}
4572 	}
4573 
4574 	return -1;
4575 }
4576 
4577 static int bond_check_params(struct bond_params *params)
4578 {
4579 	/*
4580 	 * Convert string parameters.
4581 	 */
4582 	if (mode) {
4583 		bond_mode = bond_parse_parm(mode, bond_mode_tbl);
4584 		if (bond_mode == -1) {
4585 			printk(KERN_ERR DRV_NAME
4586 			       ": Error: Invalid bonding mode \"%s\"\n",
4587 			       mode == NULL ? "NULL" : mode);
4588 			return -EINVAL;
4589 		}
4590 	}
4591 
4592 	if (xmit_hash_policy) {
4593 		if ((bond_mode != BOND_MODE_XOR) &&
4594 		    (bond_mode != BOND_MODE_8023AD)) {
4595 			printk(KERN_INFO DRV_NAME
4596 			       ": xor_mode param is irrelevant in mode %s\n",
4597 			       bond_mode_name(bond_mode));
4598 		} else {
4599 			xmit_hashtype = bond_parse_parm(xmit_hash_policy,
4600 							xmit_hashtype_tbl);
4601 			if (xmit_hashtype == -1) {
4602 				printk(KERN_ERR DRV_NAME
4603 			       	": Error: Invalid xmit_hash_policy \"%s\"\n",
4604 			       	xmit_hash_policy == NULL ? "NULL" :
4605 				       xmit_hash_policy);
4606 				return -EINVAL;
4607 			}
4608 		}
4609 	}
4610 
4611 	if (lacp_rate) {
4612 		if (bond_mode != BOND_MODE_8023AD) {
4613 			printk(KERN_INFO DRV_NAME
4614 			       ": lacp_rate param is irrelevant in mode %s\n",
4615 			       bond_mode_name(bond_mode));
4616 		} else {
4617 			lacp_fast = bond_parse_parm(lacp_rate, bond_lacp_tbl);
4618 			if (lacp_fast == -1) {
4619 				printk(KERN_ERR DRV_NAME
4620 				       ": Error: Invalid lacp rate \"%s\"\n",
4621 				       lacp_rate == NULL ? "NULL" : lacp_rate);
4622 				return -EINVAL;
4623 			}
4624 		}
4625 	}
4626 
4627 	if (max_bonds < 1 || max_bonds > INT_MAX) {
4628 		printk(KERN_WARNING DRV_NAME
4629 		       ": Warning: max_bonds (%d) not in range %d-%d, so it "
4630 		       "was reset to BOND_DEFAULT_MAX_BONDS (%d)",
4631 		       max_bonds, 1, INT_MAX, BOND_DEFAULT_MAX_BONDS);
4632 		max_bonds = BOND_DEFAULT_MAX_BONDS;
4633 	}
4634 
4635 	if (miimon < 0) {
4636 		printk(KERN_WARNING DRV_NAME
4637 		       ": Warning: miimon module parameter (%d), "
4638 		       "not in range 0-%d, so it was reset to %d\n",
4639 		       miimon, INT_MAX, BOND_LINK_MON_INTERV);
4640 		miimon = BOND_LINK_MON_INTERV;
4641 	}
4642 
4643 	if (updelay < 0) {
4644 		printk(KERN_WARNING DRV_NAME
4645 		       ": Warning: updelay module parameter (%d), "
4646 		       "not in range 0-%d, so it was reset to 0\n",
4647 		       updelay, INT_MAX);
4648 		updelay = 0;
4649 	}
4650 
4651 	if (downdelay < 0) {
4652 		printk(KERN_WARNING DRV_NAME
4653 		       ": Warning: downdelay module parameter (%d), "
4654 		       "not in range 0-%d, so it was reset to 0\n",
4655 		       downdelay, INT_MAX);
4656 		downdelay = 0;
4657 	}
4658 
4659 	if ((use_carrier != 0) && (use_carrier != 1)) {
4660 		printk(KERN_WARNING DRV_NAME
4661 		       ": Warning: use_carrier module parameter (%d), "
4662 		       "not of valid value (0/1), so it was set to 1\n",
4663 		       use_carrier);
4664 		use_carrier = 1;
4665 	}
4666 
4667 	/* reset values for 802.3ad */
4668 	if (bond_mode == BOND_MODE_8023AD) {
4669 		if (!miimon) {
4670 			printk(KERN_WARNING DRV_NAME
4671 			       ": Warning: miimon must be specified, "
4672 			       "otherwise bonding will not detect link "
4673 			       "failure, speed and duplex which are "
4674 			       "essential for 802.3ad operation\n");
4675 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4676 			miimon = 100;
4677 		}
4678 	}
4679 
4680 	/* reset values for TLB/ALB */
4681 	if ((bond_mode == BOND_MODE_TLB) ||
4682 	    (bond_mode == BOND_MODE_ALB)) {
4683 		if (!miimon) {
4684 			printk(KERN_WARNING DRV_NAME
4685 			       ": Warning: miimon must be specified, "
4686 			       "otherwise bonding will not detect link "
4687 			       "failure and link speed which are essential "
4688 			       "for TLB/ALB load balancing\n");
4689 			printk(KERN_WARNING "Forcing miimon to 100msec\n");
4690 			miimon = 100;
4691 		}
4692 	}
4693 
4694 	if (bond_mode == BOND_MODE_ALB) {
4695 		printk(KERN_NOTICE DRV_NAME
4696 		       ": In ALB mode you might experience client "
4697 		       "disconnections upon reconnection of a link if the "
4698 		       "bonding module updelay parameter (%d msec) is "
4699 		       "incompatible with the forwarding delay time of the "
4700 		       "switch\n",
4701 		       updelay);
4702 	}
4703 
4704 	if (!miimon) {
4705 		if (updelay || downdelay) {
4706 			/* just warn the user the up/down delay will have
4707 			 * no effect since miimon is zero...
4708 			 */
4709 			printk(KERN_WARNING DRV_NAME
4710 			       ": Warning: miimon module parameter not set "
4711 			       "and updelay (%d) or downdelay (%d) module "
4712 			       "parameter is set; updelay and downdelay have "
4713 			       "no effect unless miimon is set\n",
4714 			       updelay, downdelay);
4715 		}
4716 	} else {
4717 		/* don't allow arp monitoring */
4718 		if (arp_interval) {
4719 			printk(KERN_WARNING DRV_NAME
4720 			       ": Warning: miimon (%d) and arp_interval (%d) "
4721 			       "can't be used simultaneously, disabling ARP "
4722 			       "monitoring\n",
4723 			       miimon, arp_interval);
4724 			arp_interval = 0;
4725 		}
4726 
4727 		if ((updelay % miimon) != 0) {
4728 			printk(KERN_WARNING DRV_NAME
4729 			       ": Warning: updelay (%d) is not a multiple "
4730 			       "of miimon (%d), updelay rounded to %d ms\n",
4731 			       updelay, miimon, (updelay / miimon) * miimon);
4732 		}
4733 
4734 		updelay /= miimon;
4735 
4736 		if ((downdelay % miimon) != 0) {
4737 			printk(KERN_WARNING DRV_NAME
4738 			       ": Warning: downdelay (%d) is not a multiple "
4739 			       "of miimon (%d), downdelay rounded to %d ms\n",
4740 			       downdelay, miimon,
4741 			       (downdelay / miimon) * miimon);
4742 		}
4743 
4744 		downdelay /= miimon;
4745 	}
4746 
4747 	if (arp_interval < 0) {
4748 		printk(KERN_WARNING DRV_NAME
4749 		       ": Warning: arp_interval module parameter (%d) "
4750 		       ", not in range 0-%d, so it was reset to %d\n",
4751 		       arp_interval, INT_MAX, BOND_LINK_ARP_INTERV);
4752 		arp_interval = BOND_LINK_ARP_INTERV;
4753 	}
4754 
4755 	for (arp_ip_count = 0;
4756 	     (arp_ip_count < BOND_MAX_ARP_TARGETS) && arp_ip_target[arp_ip_count];
4757 	     arp_ip_count++) {
4758 		/* not complete check, but should be good enough to
4759 		   catch mistakes */
4760 		if (!isdigit(arp_ip_target[arp_ip_count][0])) {
4761 			printk(KERN_WARNING DRV_NAME
4762 			       ": Warning: bad arp_ip_target module parameter "
4763 			       "(%s), ARP monitoring will not be performed\n",
4764 			       arp_ip_target[arp_ip_count]);
4765 			arp_interval = 0;
4766 		} else {
4767 			u32 ip = in_aton(arp_ip_target[arp_ip_count]);
4768 			arp_target[arp_ip_count] = ip;
4769 		}
4770 	}
4771 
4772 	if (arp_interval && !arp_ip_count) {
4773 		/* don't allow arping if no arp_ip_target given... */
4774 		printk(KERN_WARNING DRV_NAME
4775 		       ": Warning: arp_interval module parameter (%d) "
4776 		       "specified without providing an arp_ip_target "
4777 		       "parameter, arp_interval was reset to 0\n",
4778 		       arp_interval);
4779 		arp_interval = 0;
4780 	}
4781 
4782 	if (miimon) {
4783 		printk(KERN_INFO DRV_NAME
4784 		       ": MII link monitoring set to %d ms\n",
4785 		       miimon);
4786 	} else if (arp_interval) {
4787 		int i;
4788 
4789 		printk(KERN_INFO DRV_NAME
4790 		       ": ARP monitoring set to %d ms with %d target(s):",
4791 		       arp_interval, arp_ip_count);
4792 
4793 		for (i = 0; i < arp_ip_count; i++)
4794 			printk (" %s", arp_ip_target[i]);
4795 
4796 		printk("\n");
4797 
4798 	} else {
4799 		/* miimon and arp_interval not set, we need one so things
4800 		 * work as expected, see bonding.txt for details
4801 		 */
4802 		printk(KERN_WARNING DRV_NAME
4803 		       ": Warning: either miimon or arp_interval and "
4804 		       "arp_ip_target module parameters must be specified, "
4805 		       "otherwise bonding will not detect link failures! see "
4806 		       "bonding.txt for details.\n");
4807 	}
4808 
4809 	if (primary && !USES_PRIMARY(bond_mode)) {
4810 		/* currently, using a primary only makes sense
4811 		 * in active backup, TLB or ALB modes
4812 		 */
4813 		printk(KERN_WARNING DRV_NAME
4814 		       ": Warning: %s primary device specified but has no "
4815 		       "effect in %s mode\n",
4816 		       primary, bond_mode_name(bond_mode));
4817 		primary = NULL;
4818 	}
4819 
4820 	/* fill params struct with the proper values */
4821 	params->mode = bond_mode;
4822 	params->xmit_policy = xmit_hashtype;
4823 	params->miimon = miimon;
4824 	params->arp_interval = arp_interval;
4825 	params->updelay = updelay;
4826 	params->downdelay = downdelay;
4827 	params->use_carrier = use_carrier;
4828 	params->lacp_fast = lacp_fast;
4829 	params->primary[0] = 0;
4830 
4831 	if (primary) {
4832 		strncpy(params->primary, primary, IFNAMSIZ);
4833 		params->primary[IFNAMSIZ - 1] = 0;
4834 	}
4835 
4836 	memcpy(params->arp_targets, arp_target, sizeof(arp_target));
4837 
4838 	return 0;
4839 }
4840 
4841 static int __init bonding_init(void)
4842 {
4843 	struct bond_params params;
4844 	int i;
4845 	int res;
4846 
4847 	printk(KERN_INFO "%s", version);
4848 
4849 	res = bond_check_params(&params);
4850 	if (res) {
4851 		return res;
4852 	}
4853 
4854 	rtnl_lock();
4855 
4856 #ifdef CONFIG_PROC_FS
4857 	bond_create_proc_dir();
4858 #endif
4859 
4860 	for (i = 0; i < max_bonds; i++) {
4861 		struct net_device *bond_dev;
4862 
4863 		bond_dev = alloc_netdev(sizeof(struct bonding), "", ether_setup);
4864 		if (!bond_dev) {
4865 			res = -ENOMEM;
4866 			goto out_err;
4867 		}
4868 
4869 		res = dev_alloc_name(bond_dev, "bond%d");
4870 		if (res < 0) {
4871 			free_netdev(bond_dev);
4872 			goto out_err;
4873 		}
4874 
4875 		/* bond_init() must be called after dev_alloc_name() (for the
4876 		 * /proc files), but before register_netdevice(), because we
4877 		 * need to set function pointers.
4878 		 */
4879 		res = bond_init(bond_dev, &params);
4880 		if (res < 0) {
4881 			free_netdev(bond_dev);
4882 			goto out_err;
4883 		}
4884 
4885 		SET_MODULE_OWNER(bond_dev);
4886 
4887 		res = register_netdevice(bond_dev);
4888 		if (res < 0) {
4889 			bond_deinit(bond_dev);
4890 			free_netdev(bond_dev);
4891 			goto out_err;
4892 		}
4893 	}
4894 
4895 	rtnl_unlock();
4896 	register_netdevice_notifier(&bond_netdev_notifier);
4897 	register_inetaddr_notifier(&bond_inetaddr_notifier);
4898 
4899 	return 0;
4900 
4901 out_err:
4902 	/*
4903 	 * rtnl_unlock() will run netdev_run_todo(), putting the
4904 	 * thus-far-registered bonding devices into a state which
4905 	 * unregigister_netdevice() will accept
4906 	 */
4907 	rtnl_unlock();
4908 	rtnl_lock();
4909 
4910 	/* free and unregister all bonds that were successfully added */
4911 	bond_free_all();
4912 
4913 	rtnl_unlock();
4914 
4915 	return res;
4916 }
4917 
4918 static void __exit bonding_exit(void)
4919 {
4920 	unregister_netdevice_notifier(&bond_netdev_notifier);
4921 	unregister_inetaddr_notifier(&bond_inetaddr_notifier);
4922 
4923 	rtnl_lock();
4924 	bond_free_all();
4925 	rtnl_unlock();
4926 }
4927 
4928 module_init(bonding_init);
4929 module_exit(bonding_exit);
4930 MODULE_LICENSE("GPL");
4931 MODULE_VERSION(DRV_VERSION);
4932 MODULE_DESCRIPTION(DRV_DESCRIPTION ", v" DRV_VERSION);
4933 MODULE_AUTHOR("Thomas Davis, tadavis@lbl.gov and many others");
4934 MODULE_SUPPORTED_DEVICE("most ethernet devices");
4935 
4936 /*
4937  * Local variables:
4938  *  c-indent-level: 8
4939  *  c-basic-offset: 8
4940  *  tab-width: 8
4941  * End:
4942  */
4943 
4944