Commit Graph

210 Commits

Author SHA1 Message Date
Nikolay Aleksandrov 5b3df17723 bonding: don't cast const buf in sysfs store
As was recently discussed [1], let's avoid casting the const buf in
bonding_sysfs_store_option and use kstrndup/kfree instead.

[1] http://lists.openwall.net/netdev/2018/07/22/25

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-22 10:09:30 -07:00
Joe Perches d61e403856 drivers/net: Use octal not symbolic permissions
Prefer the direct use of octal for permissions.

Done with checkpatch -f --types=SYMBOLIC_PERMS --fix-inplace
and some typing.

Miscellanea:

o Whitespace neatening around these conversions.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: Wei Liu <wei.liu2@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-26 12:07:49 -04:00
Arvind Yadav 02dbbef054 net: bonding: constify attribute_group structures.
attribute_group are not supposed to change at runtime. All functions
working with attribute_group provided by <linux/netdevice.h> work
with const attribute_group. So mark the non-const structs as const.

File size before:
   text	   data	    bss	    dec	    hex	filename
   4512	   1472	      0	   5984	   1760	drivers/net/bonding/bond_sysfs.o

File size After adding 'const':
   text	   data	    bss	    dec	    hex	filename
   4576	   1408	      0	   5984	   1760	drivers/net/bonding/bond_sysfs.o

Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-07-18 12:04:56 -07:00
Ingo Molnar 174cd4b1e5 sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>
Fix up affected files that include this signal functionality via sched.h.

Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02 08:42:32 +01:00
Jarod Wilson c8086f6d88 bonding: make mii_status sysfs node consistent
The spew in /proc/net/bonding/bond0 uses netif_carrier_ok() to determine
mii_status, while /sys/class/net/bond0/bonding/mii_status looks at
curr_active_slave, which doesn't actually seem to be set sometimes when
the bond actually is up. A mode 4 bond configured via ifcfg-foo files on a
Red Hat Enterprise Linux system, after boot, comes up clean and
functional, but the sysfs node shows mii_status of down, while proc shows
up. A simple enough fix here seems to be to use the same method for
determining up or down in both places, and I'd opt for the one that seems
to match reality.

CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <gospo@cumulusnetworks.com>
CC: netdev@vger.kernel.org
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-01-11 17:14:42 -05:00
Geliang Tang 8099c9edfd bonding: drop unused to_dev macro in bond_sysfs.c
to_dev is not used anymore so drop it.

Signed-off-by: Geliang Tang <geliangtang@163.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-12-23 22:26:48 -05:00
Nikolay Aleksandrov 205845a347 bonding: convert num_grat_arp to the new bonding option API
num_grat_arp wasn't converted to the new bonding option API, so do this
now and remove the specific sysfs store option in order to use the
standard one. num_grat_arp is the same as num_unsol_na so add it as an
alias with the same option settings. An important difference is the option
name which is matched in bond_sysfs_store_option().

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Veaceslav Falico <vfalico@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-27 01:05:24 -07:00
Mahesh Bandewar 4cd6b47544 bonding: Display LACP info only to CAP_NET_ADMIN capable user
Actor and Partner details can be accessed via proc-fs, sys-fs
entries or netlink interface. These interfaces are world readable
at this moment. The earlier patch-series made the LACP communication
secure to avoid nuisance attack from within the same L2 domain but
it did not prevent "someone unprivileged" looking at that information
on host and perform the same act.

This patch essentially avoids spitting those entries if the user
in question does not have enough privileges.

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-23 03:11:52 -07:00
Mahesh Bandewar d22a5fc0c3 bonding: Implement user key part of port_key in an AD system.
The port key has three components - user-key, speed-part, and duplex-part.
The LSBit is for the duplex-part, next 5 bits are for the speed while the
remaining 10 bits are the user defined key bits. Get these 10 bits
from the user-space (through the SysFs interface) and use it to form the
admin port-key. Allowed range for the user-key is 0 - 1023 (10 bits). If
it is not provided then use zero for the user-key-bits (default).

It can set using following example code -

   # modprobe bonding mode=4
   # usr_port_key=$(( RANDOM & 0x3FF ))
   # echo $usr_port_key > /sys/class/net/bond0/bonding/ad_user_port_key
   # echo +eth1 > /sys/class/net/bond0/bonding/slaves
   ...
   # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: * fixed up style issues reported by checkpatch
     * fixed up context from change in ad_actor_sys_prio patch]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:32 -04:00
Mahesh Bandewar 7451495755 bonding: Allow userspace to set actors' macaddr in an AD-system.
In an AD system, the communication between actor and partner is the
business between these two entities. In the current setup anyone on the
same L2 can "guess" the LACPDU contents and then possibly send the
spoofed LACPDUs and trick the partner causing connectivity issues for
the AD system. This patch allows to use a random mac-address obscuring
it's identity making it harder for someone in the L2 is do the same thing.

This patch allows user-space to choose the mac-address for the AD-system.
This mac-address can not be NULL or a Multicast. If the mac-address is set
from user-space; kernel will honor it and will not overwrite it. In the
absence (value from user space); the logic will default to using the
masters' mac as the mac-address for the AD-system.

It can be set using example code below -

   # modprobe bonding mode=4
   # sys_mac_addr=$(printf '%02x:%02x:%02x:%02x:%02x:%02x' \
                    $(( (RANDOM & 0xFE) | 0x02 )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )))
   # echo $sys_mac_addr > /sys/class/net/bond0/bonding/ad_actor_system
   # echo +eth1 > /sys/class/net/bond0/bonding/slaves
   ...
   # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: fixed up style issues reported by checkpatch]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:32 -04:00
Mahesh Bandewar 6791e4661c bonding: Allow userspace to set actors' system_priority in AD system
This patch allows user to randomize the system-priority in an ad-system.
The allowed range is 1 - 0xFFFF while default value is 0xFFFF. If user
does not specify this value, the system defaults to 0xFFFF, which is
what it was before this patch.

Following example code could set the value -
    # modprobe bonding mode=4
    # sys_prio=$(( 1 + RANDOM + RANDOM ))
    # echo $sys_prio > /sys/class/net/bond0/bonding/ad_actor_sys_prio
    # echo +eth1 > /sys/class/net/bond0/bonding/slaves
    ...
    # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: * fixed up style issues reported by checkpatch
     * changed how the default value is set in bond_check_params(), this
       makes the default consistent between what gets set for a new bond
       and what the default is claimed to be in the bonding options.]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:31 -04:00
David S. Miller 1ef8019be8 net: Move bonding headers under include/net
This ways drivers like cxgb4 don't need to do ugly relative includes.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-10 13:27:49 -05:00
Nikolay Aleksandrov 547942cace bonding: trivial: style and comment fixes
First adjust a couple of locking comments that were left inaccurate,
then adjust comments to use the netdev styling and remove extra new
lines where necessary and add a couple of new lines between declarations
and code. These are all trivial styling changes, no functional change.
Also removed a couple of outdated or obvious comments.
This patch is by no means a complete fix of all netdev style violations
but it gets the bonding closer.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-15 17:19:49 -04:00
Nikolay Aleksandrov 059b47e8aa bonding: convert primary_slave to use RCU
This is necessary mainly for two bonding call sites: procfs and
sysfs as it was dereferenced without any real protection.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-09 17:31:35 -07:00
Eric Dumazet c2646b593e bonding: use rcu_access_pointer() in bonding_show_mii_status()
curr_active_slave is rcu protected, and bonding_show_mii_status() only
wants to check if pointer is NULL or not.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Veaceslav Falico <vfalico@gmail.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-15 17:49:41 -07:00
Veaceslav Falico 01844098ec bonding: create a macro for bond mode and use it
CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-16 16:34:32 -04:00
David S. Miller 5f013c9bc7 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/altera/altera_sgdma.c
	net/netlink/af_netlink.c
	net/sched/cls_api.c
	net/sched/sch_api.c

The netlink conflict dealt with moving to netlink_capable() and
netlink_ns_capable() in the 'net' tree vs. supporting 'tc' operations
in non-init namespaces.  These were simple transformations from
netlink_capable to netlink_ns_capable.

The Altera driver conflict was simply code removal overlapping some
void pointer cast cleanups in net-next.

Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-12 13:19:14 -04:00
Nikolay Aleksandrov dc3e5d18f2 bonding: make a generic sysfs option store and fix comments
Introduce a generic option store function for sysfs and remove the
specific ones. The attribute name is used to match against the option
which is to be set.
Also adjust the "name" of tlb_dynamic_lb option to match the sysfs
entry and fix the comments and comment style in bond_sysfs.c
The comments which showed obvious behaviour (i.e. behaviour that's seen
in the option's entry) are removed, the ones that explained important
points about the setting function have been moved above the respective
set function in bond_options.c

There's only 1 exception: num_unsol_na/num_grat_arp since it has 2 names

CC: Jay Vosburgh <j.vosburgh@gmail.com>
CC: Veaceslav Falico <vfalico@gmail.com>
CC: Andy Gospodarek <andy@greyhouse.net>
CC: David S. Miller <davem@davemloft.net>

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-05-09 16:12:51 -04:00
Masanari Iida 014f1b2010 net: bonding: Fix format string mismatch in bond_sysfs.c
Fix format string mismatch in bonding_show_min_links().

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-28 14:48:16 -04:00
Mahesh Bandewar e9f0fb8849 bonding: Add tlb_dynamic_lb parameter for tlb mode
The aggresive load balancing causes packet re-ordering as active
flows are moved from a slave to another within the group. Sometime
this aggresive lb is not necessary if the preference is for less
re-ordering. This parameter if used with value "0" disables
this dynamic flow shuffling minimizing packet re-ordering. Of course
the side effect is that it has to live with the static load balancing
that the hashing distribution provides. This impact is less severe if
the correct xmit-hashing-policy is used for the tlb setup.

The default value of the parameter is set to "1" mimicing the earlier
behavior.

Ran the netperf test with 200 stream for 1 min between two hosts with
4x1G trunk (xmit-lb mode with xmit-policy L3+4) before and after these
changes. Following was the command used for those 200 instances -

    netperf -t TCP_RR -l 60 -s 5 -H <host> -- -r81920,81920

Transactions per second:
    Before change: 1,367.11
    After  change: 1,470.65

Change-Id: Ie3f75c77282cf602e83a6e833c6eb164e72a0990
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-04-24 13:04:34 -04:00
stephen hemminger f3253339a4 bonding: options handling cleanup
Make local functions static (ie. only used in bond_options.c)
Make bond options parsing tables constant.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-03-06 16:08:52 -05:00
Joe Perches 90194264ce bonding: Neaten pr_<level>
Add missing terminating newlines.
Convert uses of pr_info to pr_cont in bond_check_params.
Standardize upper/lower case styles.
Typo fixes, remove unnecessary parentheses and periods.
Alignment neatening.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-02-17 00:29:23 -05:00
Nikolay Aleksandrov 0e2e5b66e9 bonding: convert slaves to use the new option API
This patch adds the necessary changes so slaves would use
the new bonding option API. Also move the option to its own set function
in bond_options.c and fix some style errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov 4325b374f8 bonding: convert lp_interval to use the new option API
This patch adds the necessary changes so lp_interval would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov 105c8fb6c5 bonding: convert resend_igmp to use the new option API
This patch adds the necessary changes so resend_igmp would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov 3df0116251 bonding: convert all_slaves_active to use the new option API
This patch adds the necessary changes so all_slaves_active would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov 24089ba102 bonding: convert queue_id to use the new option API
This patch adds the necessary changes so queue_id would use
the new bonding option API. Also move it to its own set function in
bond_options.c and fix some style errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov d1fbd3ed93 bonding: convert active_slave to use the new option API
This patch adds the necessary changes so active_slave would use
the new bonding option API. Also some trivial/style fixes.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:44 -08:00
Nikolay Aleksandrov 0fff060877 bonding: convert use_carrier to use the new option API
This patch adds the necessary changes so use_carrier would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov 388d3a6d4a bonding: convert primary_reselect to use the new option API
This patch adds the necessary changes so primary_reselect would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov 180222f088 bonding: convert primary to use the new option API
This patch adds the necessary changes so primary would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov b98d9c66e1 bonding: convert miimon to use the new option API
This patch adds the necessary changes so miimon would use
the new bonding option API. The "default" definition has been removed as
it was 0.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov ef56becbb3 bonding: convert num_peer_notif to use the new option API
This patch adds the necessary changes so num_peer_notif would use
the new bonding option API.
When the auto-sysfs generation is done an alias should be added for
this option as there're currently 2 entries in sysfs for it.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov 9e5f5eebe7 bonding: convert ad_select to use the new option API
This patch adds the necessary changes so ad_select would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov 633ddc9e9b bonding: convert min_links to use the new option API
This patch adds the necessary changes so min_links would use
the new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:43 -08:00
Nikolay Aleksandrov d3131de76b bonding: convert lacp_rate to use the new option API
This patch adds the necessary changes so lacp_rate would use
the new bonding option API. Also some trivial/style error fixes.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov e499461275 bonding: convert updelay to use the new option API
This patch adds the necessary changes so updelay would use
the new bonding option API. Also some trivial style fixes.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov 25a9b54a4b bonding: convert downdelay to use the new option API
This patch adds the necessary changes so downdelay would use
the new bonding option API. Also some trivial style fixes.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov 4fb0ef585e bonding: convert arp_ip_target to use the new option API
This patch adds the necessary changes so arp_ip_target would use
the new bonding option API. This option is an exception because of
the way it's currently implemented that's why its netlink code is
a bit different from the other options to keep the functionality as
before and at the same time to have a single set function.

This patch also fixes a few stylistic errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov 7bdb04ed0d bonding: convert arp_interval to use the new option API
This patch adds the necessary changes so arp_interval would use
the new bonding option API. The "default" definition has been removed as
it was 0.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov 1df6b6aa33 bonding: convert fail_over_mac to use the new option API
This patch adds the necessary changes so fail_over_mac would use
the new bonding option API. Also fixes a trivial copy/paste error in
bond_check_params where the wrong variable was used for the error msg.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov edf36b24c5 bonding: convert arp_all_targets to use the new option API
This patch adds the necessary changes so arp_all_targets would use the
new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov 162288810c bonding: convert arp_validate to use the new option API
This patch adds the necessary changes so arp_validate would use the
new bonding option API. Also fix some trivial/style errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:42 -08:00
Nikolay Aleksandrov a4b32ce7f8 bonding: convert xmit_hash_policy to use the new option API
This patch adds the necessary changes so xmit_hash_policy would use the
new bonding option API. Also fix some trivial/style errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:41 -08:00
Nikolay Aleksandrov aa59d8517d bonding: convert packets_per_slave to use the new option API
This patch adds the necessary changes so packets_per_slave would use the
new bonding option API.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:41 -08:00
Nikolay Aleksandrov 2b3798d5e1 bonding: convert mode setting to use the new option API
This patch makes the bond's mode setting use the new option API and
adds support for dependency printing which relies on having an entry for
the mode option in the bond_opts[] array.
Also add the ability to print the mode name when mode dependency fails
and fix some trivial/style errors.

Signed-off-by: Nikolay Aleksandrov <nikolay@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-22 15:38:41 -08:00
Hannes Frederic Sowa 809fa972fd reciprocal_divide: update/correction of the algorithm
Jakub Zawadzki noticed that some divisions by reciprocal_divide()
were not correct [1][2], which he could also show with BPF code
after divisions are transformed into reciprocal_value() for runtime
invariance which can be passed to reciprocal_divide() later on;
reverse in BPF dump ended up with a different, off-by-one K in
some situations.

This has been fixed by Eric Dumazet in commit aee636c480
("bpf: do not use reciprocal divide"). This follow-up patch
improves reciprocal_value() and reciprocal_divide() to work in
all cases by using Granlund and Montgomery method, so that also
future use is safe and without any non-obvious side-effects.
Known problems with the old implementation were that division by 1
always returned 0 and some off-by-ones when the dividend and divisor
where very large. This seemed to not be problematic with its
current users, as far as we can tell. Eric Dumazet checked for
the slab usage, we cannot surely say so in the case of flex_array.
Still, in order to fix that, we propose an extension from the
original implementation from commit 6a2d7a955d resp. [3][4],
by using the algorithm proposed in "Division by Invariant Integers
Using Multiplication" [5], Torbjörn Granlund and Peter L.
Montgomery, that is, pseudocode for q = n/d where q, n, d is in
u32 universe:

1) Initialization:

  int l = ceil(log_2 d)
  uword m' = floor((1<<32)*((1<<l)-d)/d)+1
  int sh_1 = min(l,1)
  int sh_2 = max(l-1,0)

2) For q = n/d, all uword:

  uword t = (n*m')>>32
  q = (t+((n-t)>>sh_1))>>sh_2

The assembler implementation from Agner Fog [6] also helped a lot
while implementing. We have tested the implementation on x86_64,
ppc64, i686, s390x; on x86_64/haswell we're still half the latency
compared to normal divide.

Joint work with Daniel Borkmann.

  [1] http://www.wireshark.org/~darkjames/reciprocal-buggy.c
  [2] http://www.wireshark.org/~darkjames/set-and-dump-filter-k-bug.c
  [3] https://gmplib.org/~tege/division-paper.pdf
  [4] http://homepage.cs.uiowa.edu/~jones/bcd/divide.html
  [5] http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1.2556
  [6] http://www.agner.org/optimize/asmlib.zip

Reported-by: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Austin S Hemmelgarn <ahferroin7@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: Jesse Gross <jesse@nicira.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Matt Mackall <mpm@selenic.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: Veaceslav Falico <vfalico@redhat.com>
Cc: Jay Vosburgh <fubar@us.ibm.com>
Cc: Jakub Zawadzki <darkjames-ws@darkjames.pl>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-21 23:17:20 -08:00
Veaceslav Falico 0b23810d8c bonding: fix kstrtou8() return value verification in num_peer_notif
It returns 0 in case of success, !0 error otherwise. Fix the improper error
verification.

Fixes: 2c9839c143 ("bonding: add num_grat_arp attribute netlink support")
CC: sfeldma@cumulusnetworks.com
CC: Jay Vosburgh <fubar@us.ibm.com>
CC: Andy Gospodarek <andy@greyhouse.net>
Signed-off-by: Veaceslav Falico <vfalico@redhat.com>
Acked-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-06 16:26:00 -05:00
sfeldma@cumulusnetworks.com ec029fac3e bonding: add ad_select attribute netlink support
Add IFLA_BOND_AD_SELECT to allow get/set of bonding parameter
ad_select via netlink.

Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-03 21:03:21 -05:00
sfeldma@cumulusnetworks.com 998e40bbf8 bonding: add lacp_rate attribute netlink support
Add IFLA_BOND_AD_LACP_RATE to allow get/set of bonding parameter
lacp_rate via netlink.

Signed-off-by: Scott Feldman <sfeldma@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-03 21:03:21 -05:00