I found the PPP subsystem to not work properly when connecting channels
with different speeds to the same bundle.
Problem Description:
As the "ppp_mp_explode" function fragments the sk_buff buffer evenly
among the PPP channels that are connected to a certain PPP unit to
make up a bundle, if we are transmitting using an upper layer protocol
that requires an Ack before sending the next packet (like TCP/IP for
example), we will have a bandwidth bottleneck on the slowest channel
of the bundle.
Let's clarify by an example. Let's consider a scenario where we have
two PPP links making up a bundle: a slow link (10KB/sec) and a fast
link (1000KB/sec) working at the best (full bandwidth). On the top we
have a TCP/IP stack sending a 1000 Bytes sk_buff buffer down to the
PPP subsystem. The "ppp_mp_explode" function will divide the buffer in
two fragments of 500B each (we are neglecting all the headers, crc,
flags etc?.). Before the TCP/IP stack sends out the next buffer, it
will have to wait for the ACK response from the remote peer, so it
will have to wait for both fragments to have been sent over the two
PPP links, received by the remote peer and reconstructed. The
resulting behaviour is that, rather than having a bundle working
@1010KB/sec (the sum of the channels bandwidths), we'll have a bundle
working @20KB/sec (the double of the slowest channels bandwidth).
Problem Solution:
The problem has been solved by redesigning the "ppp_mp_explode"
function in such a way to make it split the sk_buff buffer according
to the speeds of the underlying PPP channels (the speeds of the serial
interfaces respectively attached to the PPP channels). Referring to
the above example, the redesigned "ppp_mp_explode" function will now
divide the 1000 Bytes buffer into two fragments whose sizes are set
according to the speeds of the channels where they are going to be
sent on (e.g . 10 Byets on 10KB/sec channel and 990 Bytes on
1000KB/sec channel). The reworked function grants the same
performances of the original one in optimal working conditions (i.e. a
bundle made up of PPP links all working at the same speed), while
greatly improving performances on the bundles made up of channels
working at different speeds.
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove some pointless conditionals before kfree_skb().
Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix this sparse warnings:
drivers/net/ppp_generic.c:919:43: warning: incorrect type in argument 1 (different signedness)
drivers/net/pppoe.c:1195:43: warning: incorrect type in argument 1 (different signedness)
drivers/net/pppol2tp.c:2666:43: warning: incorrect type in argument 1 (different signedness)
Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
PPP is modular code so no initdata on netns hooks.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- Each namespace contains ppp channels and units separately
with appropriate locks
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commits:
7a95d267fb
("net: ppp_generic - use idr technique instead of cardmaps")
ab5024ab23
("net: ppp_generic - use DEFINE_IDR for static initialization")
introduced usage of IDR functionality but broke userspace side.
Before this commits it was possible to allocate new ppp interface with
specified number. Now it fails with EINVAL. Fix it by trying to
allocate interface with specified unit number and return EEXIST if
fail which allow pppd to ask us to allocate new unit number.
And fix messages on memory allocation fails - add details that it's
PPP module who is complaining.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
We could use DEFINE_IDR for statically allocated idr
that allow us to save a few lines of code.
And spell fix.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fixes a segfault in ppp_shutdown_interface() and
ppp_destroy_interface() when a PPP connection is closed. I bisected
the problem to the following commit:
commit c8019bf3af
Author: Wang Chen <wangchen@cn.fujitsu.com>
Date: Thu Nov 20 04:24:17 2008 -0800
netdevice ppp: Convert directly reference of netdev->priv
1. Use netdev_priv(dev) to replace dev->priv.
2. Alloc netdev's private data by alloc_netdev().
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The original ppp_generic code treated the netdev and struct ppp as
independent data structures which were freed separately. In moving the
ppp struct into the netdev, it is now possible for the private data to
be freed before the call to ppp_shutdown_interface(), which is bad.
The kfree(ppp) in ppp_destroy_interface() is also wrong; presumably
ppp hasn't worked since the above commit.
The following patch fixes both problems.
Signed-off-by: James Chapman <jchapman@katalix.com>
Reviewed-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use idr technique instead of own implemented cardmaps.
It saves us a number of lines and gives an ability
to use library functions.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves neigh_setup and hard_start_xmit into the network device ops
structure. For bisection, fix all the previously converted drivers as well.
Bonding driver took the biggest hit on this.
Added a prefetch of the hard_start_xmit in the fast path to try and reduce
any impact this would have.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1. Use netdev_priv(dev) to replace dev->priv.
2. Alloc netdev's private data by alloc_netdev().
Signed-off-by: Wang Chen <wangchen@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Convert this driver to network device ops. Compile tested only.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The generic packet receive code takes care of setting
netdev->last_rx when necessary, for the sake of the
bonding ARP monitor.
Drivers need not do it any more.
Some cases had to be skipped over because the drivers
were making use of the ->last_rx value themselves.
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core-2.6: (46 commits)
UIO: Fix mapping of logical and virtual memory
UIO: add automata sercos3 pci card support
UIO: Change driver name of uio_pdrv
UIO: Add alignment warnings for uio-mem
Driver core: add bus_sort_breadthfirst() function
NET: convert the phy_device file to use bus_find_device_by_name
kobject: Cleanup kobject_rename and !CONFIG_SYSFS
kobject: Fix kobject_rename and !CONFIG_SYSFS
sysfs: Make dir and name args to sysfs_notify() const
platform: add new device registration helper
sysfs: use ilookup5() instead of ilookup5_nowait()
PNP: create device attributes via default device attributes
Driver core: make bus_find_device_by_name() more robust
usb: turn dev_warn+WARN_ON combos into dev_WARN
debug: use dev_WARN() rather than WARN_ON() in device_pm_add()
debug: Introduce a dev_WARN() function
sysfs: fix deadlock
device model: Do a quickcheck for driver binding before doing an expensive check
Driver core: Fix cleanup in device_create_vargs().
Driver core: Clarify device cleanup.
...
Now that device_create() has been audited, rename things back to the
original call to be sane.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Straight forward conversions to CONFIG_MODULE; many drivers
include <linux/kmod.h> conditionally and then don't have any
other conditional code so remove it from those.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: video4linux-list@redhat.com
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: linux-ppp@vger.kernel.org
Cc: dm-devel@redhat.com
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This minor cleanup simplifies later changes which will convert
struct sk_buff and friends over to using struct list_head.
Signed-off-by: David S. Miller <davem@davemloft.net>
make it atomic_long_t; while we are at it, get rid of useless checks in affs,
hfs and hpfs - ->open() always has it equal to 1, ->release() - to 0.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
device_create() is race-prone, so use the race-free
device_create_drvdata() instead as device_create() is going away.
Cc: Jeff Garzik <jgarzik@pobox.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
All of the open() functions which don't need the BKL on their face may
still depend on its acquisition to serialize opens against driver
initialization. So make those functions acquire then release the BKL to be
on the safe side.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
This documents the fact that somebody looked at the relevant open()
functions and concluded that, due to their trivial nature, no locking was
needed.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
I've pushed it down as far as I dare at this point. Someone familiar with
the internal PPP semantics can probably push it further. Another step to
eliminating the old BKL ioctl usage.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
An error path in ppp_create_interface() lacks one and may
BUG in free_netdev() checking for proper dev->reg_state.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use stats which now is in the net_device instead of one declared in
ppp structure.
Kill ppp_net_stats function, because by default it is used identical
internal_stats function from net/core/dev.c
Signed-of-by: Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix a bunch of warnings in PPP and related drivers. Mostly because
sparse doesn't like it when the the function is only marked private in
the forward declaration.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fix sparse warnings "Using plain integer as NULL pointer"
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds missing pskb_may_pull calls to deal with non-linear
packets that may arrive from pppoe or pppol2tp.
It also copies cloned packets before writing over them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
It's rude to write over data that other people are still using. So call
skb_cow_head before PPP proceeds to modify the skb data.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch addresses the issue with "osize too small" errors in mppe
encryption. The patch fixes the issue with wrong output buffer size
being passed to ppp decompression routine.
--------------------
As pointed out by Suresh Mahalingam, the issue addressed by
ppp-fix-osize-too-small-errors-when-decoding patch is not fully resolved yet.
The size of allocated output buffer is correct, however it size passed to
ppp->rcomp->decompress in ppp_generic.c if wrong. The patch fixes that.
--------------------
Signed-off-by: Konstantin Sharlaimov <konstantin.sharlaimov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
unregister_chrdev() always returns 0. There is no need to check the return
value.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The mppe_decompress() function required a buffer that is 1 byte too
small when receiving a message of mru size. This fixes buffer
allocation to prevent this from occurring.
Signed-off-by: Konstantin Sharlaimov <konstantin.sharlaimov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.
Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
ROUND_UP macro cleanup use DIV_ROUND_UP
Signed-off-by: Milind Arun Choudhary <milindchoudhary@gmail.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can
later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in
64bit land while possibly keeping it as a pointer on 32bit.
This one touches just the most simple case, next will handle the slightly more
"complex" cases.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Many struct file_operations in the kernel can be "const". Marking them const
moves these to the .rodata section, which avoids false sharing with potential
dirty data. In addition it'll catch accidental writes at compile time to
these shared resources.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Replace a small number of expressions with a call to the "container_of()"
macro.
Signed-off-by: Robert P. J. Day <rpjday@mindspring.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Converts from using struct "class_device" to "struct device" making
everything show up properly in /sys/devices/ with symlinks from the
/sys/class directory.
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
The PPP code contains two kmalloc()s followed by memset()s without
handling a possible memory allocation failure. (Suggested by Joe
Perches).
And furthermore, conversions from kmalloc+memset to kzalloc.
[akpm@osdl.org: fix error-path leak]
[akpm@osdl.org: cleanups]
[paulus@samba.org: don't add useless printk and cardmap_destroy calls]
Signed-off-by: Panagiotis Issaris <takis@issaris.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts the combination of list_del(A) and list_add(A, B) to
list_move(A, B) under drivers/.
Acked-by: Corey Minyard <minyard@mvista.com>
Cc: Ben Collins <bcollins@debian.org>
Acked-by: Roland Dreier <rolandd@cisco.com>
Cc: Alasdair Kergon <dm-devel@redhat.com>
Cc: Gerd Knorr <kraxel@bytesex.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Frank Pavlic <fpavlic@de.ibm.com>
Acked-by: Matthew Wilcox <matthew@wil.cx>
Cc: Andrew Vasquez <linux-driver@qlogic.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Signed-off-by: Akinobu Mita <mita@miraclelinux.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
