pskb_expand_head() blindly takes references on fragments before calling
skb_release_data(), potentially releasing these references.
We can add a fast path, avoiding these atomic operations, if we own the
last reference on skb->head.
Based on a previous patch from David
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__alloc_skb() uses a memset() to clear all the beginning of skb,
including bitfields contained in 'flags1' & 'flags2'.
We dont need any more to use kmemcheck_annotate_bitfield() on these
fields. However, we still need it for the clone part, which is not
cleared.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add a small helper ptype_head() to get the head to manipulate
dev_add_pack() & __dev_remove_pack() can use a spinlock without
blocking BH, since softirq use RCU, and these functions are run from
process context only.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(skb->data - skb->head) can be changed by skb_headroom(skb)
Remove some uses of NET_SKBUFF_DATA_USES_OFFSET, using
(skb_end_pointer(skb) - skb->head) or
(skb_tail_pointer(skb) - skb->head) : compiler does the right thing,
and this is more readable for us ;)
(struct skb_shared_info *) casts in pskb_expand_head() to help memcpy()
to use aligned moves.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
- napi_gro_flush() is exported from net/core/dev.c, to avoid
an irq_save/irq_restore in the packet receive path.
- use napi_gro_receive() instead of netif_receive_skb()
- use napi_gro_flush() before calling __napi_complete()
- turn on NETIF_F_GRO by default
- Tested on a Marvell 88E8001 Gigabit NIC
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
remove non used variable "queue" in pg_cleanup
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
compare_ether_header() can have a special implementation on 64 bit
arches if CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS is defined.
__napi_gro_receive() and vlan_gro_common() can avoid a conditional
branch to perform device match.
On x86_64, __napi_gro_receive() has now 38 instructions instead of 53
As gcc-4.4.3 still choose to not inline it, add inline keyword to this
performance critical function.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The SNMP daemon uses ethtool to determine the speed of
network interfaces. This fails on Debian (and probably elsewhere)
because for security SNMP daemon runs as non-root user (snmp).
Note: A similar patch was rejected previously because of a concern about
the possibility that on some hardware querying the ethtool settings
requires access to the PHY and could slow the machine down. But the
security risk of requiring SNMP daemon (and related services)
to run as root far out weighs the risk of denial-of-service.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
No need to use a temporary struct rtnl_link_stats64 variable,
just copy the source to skb buffer.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
SKBs can be "fragmented" in two ways, via a page array (called
skb_shinfo(skb)->frags[]) and via a list of SKBs (called
skb_shinfo(skb)->frag_list).
Since skb_has_frags() tests the latter, it's name is confusing
since it sounds more like it's testing the former.
Signed-off-by: David S. Miller <davem@davemloft.net>
vlan_hwaccel_do_receive() always returns 0, so make it return void.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
__skb_get_rxhash() was broken after the commit:
commit bfb564e739
Author: Krishna Kumar <krkumar2@in.ibm.com>
Date: Wed Aug 4 06:15:52 2010 +0000
core: Factor out flow calculation from get_rps_cpu
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fragmented IP packets may have no transfer header, so when computing
rxhash, we should skip them.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
skb_get_rxhash() assumes the network header pointer of the skb is set
properly after the commit:
commit bfb564e739
Author: Krishna Kumar <krkumar2@in.ibm.com>
Date: Wed Aug 4 06:15:52 2010 +0000
core: Factor out flow calculation from get_rps_cpu
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch removes the abstraction introduced by the union skb_shared_tx in
the shared skb data.
The access of the different union elements at several places led to some
confusion about accessing the shared tx_flags e.g. in skb_orphan_try().
http://marc.info/?l=linux-netdev&m=128084897415886&w=2
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
>Xin Xiaohui wrote:
> I looked into the code dev_gro_receive(), found the code here:
> if the frags[0] is pulled to 0, then the page will be released,
> and memmove() frags left.
> Is that right? I'm not sure if memmove do right or not, but
> frags[0].size is never set after memove at least. what I think
> a simple way is not to do anything if we found frags[0].size == 0.
> The patch is as followed.
...
This version of the patch fixes the bug directly in memmove.
Reported-by: "Xin, Xiaohui" <xiaohui.xin@intel.com>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The driver name and bus address for a net_device can normally be found
through the driver model now. Instead of requiring drivers to provide
this information redundantly through the ethtool_ops::get_drvinfo
operation, use the driver model to do so if the driver does not define
the operation. Since ETHTOOL_GDRVINFO no longer requires the driver
to implement any operations, do not require net_device::ethtool_ops to
be set either.
Remove implementations of get_drvinfo and ethtool_ops that provide
only this information.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Factor out flow calculation code from get_rps_cpu, since other
functions can use the same code.
Revisions:
v2 (Ben): Separate flow calcuation out and use in select queue.
v3 (Arnd): Don't re-implement MIN.
v4 (Changli): skb->data points to ethernet header in macvtap, and
make a fast path. Tested macvtap with this patch.
v5 (Changli):
- Cache skb->rxhash in skb_get_rxhash
- macvtap may not have pow(2) queues, so change code for
queue selection.
(Arnd):
- Use first available queue if all fails.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Enable using network namespaces with
wireless devices even when sysfs is
enabled using the same infrastructure
that was built for netdevs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Although netif_rx() isn't expected to be called in process context with
preemption enabled, it'd better handle this case. And this is why get_cpu()
is used in the non-RPS #ifdef branch. If tree RCU is selected,
rcu_read_lock() won't disable preemption, so preempt_disable() should be
called explictly.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netpoll_rx_on() check in __napi_gro_receive() skips part of the
"common" GRO_NORMAL path, especially "pull:" in dev_gro_receive(),
where at least eth header should be copied for entirely paged skbs.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This reverts commit 15e83ed788.
As explained by Johannes Berg, the optimization made here is
invalid. Or, at best, incomplete.
Not only destructor invocation, but conntract entry releasing
must be executed outside of hw IRQ context.
So just checking "skb->destructor" is insufficient.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit ab95bfe01f replaces bridge and macvlan
hooks in __netif_receive_skb(), so dev.c doesn't need to include their headers.
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
If user misconfigures ingress and causes a redirection loop, don't
overwhelm the log. This is also a error case so make it unlikely.
Found by inspection, luckily not in real system.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[ Fix unused local variable build warnings. -DaveM ]
Signed-off-by: Changli Gao <xiaosuo@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With conn-track zones and probably with different network
namespaces, the netfilter logic needs to be re-calculated
on packet receive. If the netfilter logic is not reset,
it will not be recalculated properly. This patch adds
the nf_reset logic to dev_forward_skb.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Move frags[] at the end of struct skb_shared_info, and make
pskb_expand_head() copy only the used part of it instead of whole array.
This should avoid kmemcheck warnings and speedup pskb_expand_head() as
well, avoiding a lot of cache misses.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add addr_assign_type to struct net_device and expose it via sysfs.
This new attribute has the purpose of giving user-space the ability to
distinguish between different assignment types of MAC addresses.
For example user-space can treat NICs with randomly generated MAC
addresses differently than NICs that have permanent (locally assigned)
MAC addresses.
For the former udev could write a persistent net rule by matching the
device path instead of the MAC address.
There's also the case of devices that 'steal' MAC addresses from slave
devices. In which it is also be beneficial for user-space to be aware
of the fact.
This patch also introduces a helper function to assist adoption of
drivers that generate MAC addresses randomly.
Signed-off-by: Stefan Assmann <sassmann@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Make pskb_expand_head() check ip_summed to make sure csum_start is really
csum_start and not csum before adjusting it.
This fixes a bug I encountered using a Sun Quad-Fast Ethernet card and VLANs.
On my configuration, the sunhme driver produces skbs with differing amounts
of headroom on receive depending on the packet size. See line 2030 of
drivers/net/sunhme.c; packets smaller than RX_COPY_THRESHOLD have 52 bytes
of headroom but packets larger than that cutoff have only 20 bytes.
When these packets reach the VLAN driver, vlan_check_reorder_header()
calls skb_cow(), which, if the packet has less than NET_SKB_PAD (== 32) bytes
of headroom, uses pskb_expand_head() to make more.
Then, pskb_expand_head() needs to adjust a lot of offsets into the skb,
including csum_start. Since csum_start is a union with csum, if the packet
has a valid csum value this will corrupt it, which was the effect I observed.
The sunhme hardware computes receive checksums, so the skbs would be created
by the driver with ip_summed == CHECKSUM_COMPLETE and a valid csum field, and
then pskb_expand_head() would corrupt the csum field, leading to an "hw csum
error" message later on, for example in icmp_rcv() for pings larger than the
sunhme RX_COPY_THRESHOLD.
On the basis of the comment at the beginning of include/linux/skbuff.h,
I believe that the csum_start skb field is only meaningful if ip_csummed is
CSUM_PARTIAL, so this patch makes pskb_expand_head() adjust it only in that
case to avoid corrupting a valid csum value.
Please see my more in-depth disucssion of tracking down this bug for
more details if you like:
http://puellavulnerata.livejournal.com/112186.htmlhttp://puellavulnerata.livejournal.com/112567.htmlhttp://puellavulnerata.livejournal.com/112891.htmlhttp://puellavulnerata.livejournal.com/113096.htmlhttp://puellavulnerata.livejournal.com/113591.html
I am not subscribed to this list, so please CC me on replies.
Signed-off-by: Andrea Shepard <andrea@persephoneslair.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
drivers/vhost/net.c
net/bridge/br_device.c
Fix merge conflict in drivers/vhost/net.c with guidance from
Stephen Rothwell.
Revert the effects of net-2.6 commit 573201f36f
since net-next-2.6 has fixes that make bridge netpoll work properly thus
we don't need it disabled.
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch to add -EAGAIN error to dropwatch netlink message handling code.
-EAGAIN will be returned anytime userspace attempts to transition the state of
the drop monitor service to a state that its already in. That allows user space
to detect this condition, so it doesn't wait for a success ACK that will never
arrive. Tested successfully by me
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Use modern this_cpu_xxx() api, saving few bytes on x86
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since struct netdev_queue tx_bytes/tx_packets/tx_dropped are already
protected by _xmit_lock, its easy to convert these fields to u64 instead
of unsigned long.
This completes 64bit stats for devices using them (vlan, macvlan, ...)
Strictly, we could avoid the locking in dev_txq_stats_fold() on 64bit
arches, but its slow path and we prefer keep it simple.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a new networking option to allow hardware time stamps
from PHY devices. When enabled, likely candidates among incoming and
outgoing network packets are offered to the PHY driver for possible
time stamping. When accepted by the PHY driver, incoming packets are
deferred for later delivery by the driver.
The patch also adds phylib driver methods for the SIOCSHWTSTAMP ioctl
and callbacks for transmit and receive time stamping. Drivers may
optionally implement these functions.
Signed-off-by: Richard Cochran <richard.cochran@omicron.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix problem in reading the tx_queue recorded in a socket. In
dev_pick_tx, the TX queue is read by doing a check with
sk_tx_queue_recorded on the socket, followed by a sk_tx_queue_get.
The problem is that there is not mutual exclusion across these
calls in the socket so it it is possible that the queue in the
sock can be invalidated after sk_tx_queue_recorded is called so
that sk_tx_queue get returns -1, which sets 65535 in queue_index
and thus dev_pick_tx returns 65536 which is a bogus queue and
can cause crash in dev_queue_xmit.
We fix this by only calling sk_tx_queue_get which does the proper
checks. The interface is that sk_tx_queue_get returns the TX queue
if the sock argument is non-NULL and TX queue is recorded, else it
returns -1. sk_tx_queue_recorded is no longer used so it can be
completely removed.
Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When configuring DMVPN (GRE + openNHRP) and a GRE remote
address is configured a kernel Oops is observed. The
obserseved Oops is caused by a NULL header_ops pointer
(neigh->dev->header_ops) in neigh_update_hhs() when
void (*update)(struct hh_cache*, const struct net_device*, const unsigned char *)
= neigh->dev->header_ops->cache_update;
is executed. The dev associated with the NULL header_ops is
the GRE interface. This patch guards against the
possibility that header_ops is NULL.
This Oops was first observed in kernel version 2.6.26.8.
Signed-off-by: Doug Kehn <rdkehn@yahoo.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit fc6055a5ba (net: Introduce skb_orphan_try()) added early
orphaning of skbs.
This unfortunately added a performance regression in skb_tx_hash() in
case of stacked devices (bonding, vlans, ...)
Since skb->sk is now NULL, we cannot access sk->sk_hash anymore to
spread tx packets to multiple NIC queues on multiqueue devices.
skb_tx_hash() in this case only uses skb->protocol, same value for all
flows.
skb_orphan_try() can copy sk->sk_hash into skb->rxhash and skb_tx_hash()
can use this saved sk_hash value to compute its internal hash value.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Avoid two extra instructions in sock_free(), to reload
skb->truesize and skb->sk
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
CodingStyle cleanups
EXPORT_SYMBOL should immediately follow the symbol declaration.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Document that dev_get_stats() returns the same stats pointer it was
given. Remove const qualification from the returned pointer since the
caller may do what it likes with that structure.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In commit be1f3c2c02 "net: Enable 64-bit
net device statistics on 32-bit architectures" I redefined struct
net_device_stats so that it could be used in a union with struct
rtnl_link_stats64, avoiding the need for explicit copying or
conversion between the two. However, this is unsafe because there is
no locking required and no lock consistently held around calls to
dev_get_stats() and use of the statistics structure it returns.
In commit 28172739f0 "net: fix 64 bit
counters on 32 bit arches" Eric Dumazet dealt with that problem by
requiring callers of dev_get_stats() to provide storage for the
result. This means that the net_device::stats64 field and the padding
in struct net_device_stats are now redundant, so remove them.
Update the comment on net_device_ops::ndo_get_stats64 to reflect its
new usage.
Change dev_txq_stats_fold() to use struct rtnl_link_stats64, since
that is what all its callers are really using and it is no longer
going to be compatible with struct net_device_stats.
Eric Dumazet suggested the separate function for the structure
conversion.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet
stephen hemminger
John W. Linville
David S. Miller
Changli Gao
Oliver Hartkopp
Jarek Poplawski
Ben Hutchings
Krishna Kumar
Johannes Berg
Ben Greear
Stefan Assmann
Andy Shevchenko
Andrea Shepard
Neil Horman
Nicolas Dichtel
Richard Cochran
Tom Herbert
Doug Kehn
Joe Perches