String literals are constant, and usually, we can also tag the array
of pointers const too, moving it to the .rodata section.
Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is a path when an assetion in dev_unicast_sync() appears.
igmp6_group_added -> dev_mc_add -> __dev_set_rx_mode ->
-> vlan_dev_set_rx_mode -> dev_unicast_sync
Therefore we cannot protect this list with rtnl. This patch restores the
original protecting this list with spinlock.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Tested-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to make cfg80211/nl80211 aware of network namespaces,
we have to do the following things:
* del_virtual_intf method takes an interface index rather
than a netdev pointer - simply change this
* nl80211 uses init_net a lot, it changes to use the sender's
network namespace
* scan requests use the interface index, hold a netdev pointer
and reference instead
* we want a wiphy and its associated virtual interfaces to be
in one netns together, so
- we need to be able to change ns for a given interface, so
export dev_change_net_namespace()
- for each virtual interface set the NETIF_F_NETNS_LOCAL
flag, and clear that flag only when the wiphy changes ns,
to disallow breaking this invariant
* when a network namespace goes away, we need to reparent the
wiphy to init_net
* cfg80211 users that support creating virtual interfaces must
create them in the wiphy's namespace, currently this affects
only mac80211
The end result is that you can now switch an entire wiphy into
a different network namespace with the new command
iw phy#<idx> set netns <pid>
and all virtual interfaces will follow (or the operation fails).
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For mac80211, with the master netdev removal, we need to be
able to sync a multicast address list onto another list that
is not tracked within a netdev, so we need access to the
functions doing that.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch converts the remaining occurences of raw return values to their
symbolic counterparts in ndo_start_xmit() functions that were missed by the
previous automatic conversion.
Additionally code that assumed the symbolic value of NETDEV_TX_OK to be zero
is changed to explicitly use NETDEV_TX_OK.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
When NAPI is disabled while we're in net_rx_action, we end up
calling __napi_complete without flushing GRO packets. This is
a bug as it would cause the GRO packets to linger, of course it
also literally BUGs to catch error like this :)
This patch changes it to napi_complete, with the obligatory IRQ
reenabling. This should be safe because we've only just disabled
IRQs and it does not materially affect the test conditions in
between.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to get the tun driver to account packets, we need to be
able to receive packets with destructors set. To be on the safe
side, I added an skb_orphan call for all protocols by default since
some of them (IP in particular) cannot handle receiving packets
destructors properly.
Now it seems that at least one protocol (CAN) expects to be able
to pass skb->sk through the rx path without getting clobbered.
So this patch attempts to fix this properly by moving the skb_orphan
call to where it's actually needed. In particular, I've added it
to skb_set_owner_[rw] which is what most users of skb->destructor
call.
This is actually an improvement for tun too since it means that
we only give back the amount charged to the socket when the skb
is passed to another socket that will also be charged accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Oliver Hartkopp <olver@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is inspired by patch recently posted by Johannes Berg. Basically what
my patch does is to group list and a count of addresses into newly introduced
structure netdev_hw_addr_list. This brings us two benefits:
1) struct net_device becames a bit nicer.
2) in the future there will be a possibility to operate with lists independently
on netdevices (with exporting right functions).
I wanted to introduce this patch before I'll post a multicast lists conversion.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
drivers/net/bnx2.c | 4 +-
drivers/net/e1000/e1000_main.c | 4 +-
drivers/net/ixgbe/ixgbe_main.c | 6 +-
drivers/net/mv643xx_eth.c | 2 +-
drivers/net/niu.c | 4 +-
drivers/net/virtio_net.c | 10 ++--
drivers/s390/net/qeth_l2_main.c | 2 +-
include/linux/netdevice.h | 17 +++--
net/core/dev.c | 130 ++++++++++++++++++--------------------
9 files changed, 89 insertions(+), 90 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch changes FDB entry check for ATM LANE bridge integration.
There's no point in holding a FDB entry around SKB building.
br_fdb_get()/br_fdb_put() pair are changed into single br_fdb_test_addr()
hook that checks if the addr has FDB entry pointing to other port
to the one the request arrived on.
FDB entry refcounting is removed as it's not used anywhere else.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit b00055aacd " [NET] core: add
RFC2863 operstate" defined new interface flag values. Its
documentation specified that these flags could be accessed from user
space via SIOCGIFFLAGS. However, this does not work because the new
flags do not fit in that ioctl's argument width.
Change the documentation to match the code's behavior. Also change
the source to explicitly show the truncation. This _should_ have no
effect on executable code, and did not with gcc 4.2.4 generating x86
code.
A new ioctl could be defined to return all interface flags to user
space. However, since this has been broken for three years with no
one complaining, there doesn't seem much need. They are still
accessible via netlink.
Reported-by: "Fredrik Arnerup" <fredrik.arnerup@edgeware.tv>
Signed-off-by: John Dykstra <john.dykstra1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
IEEE 802.15.4 stack requires several constants to be defined/adjusted.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Sergey Lapin <slapin@ossfans.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
commit f001fde5ea
(net: introduce a list of device addresses dev_addr_list (v6))
added one regression Vegard Nossum found in its testings.
With kmemcheck help, Vegard found some uninitialized memory
was read and reported to user, potentialy leaking kernel data.
( thread can be found on http://lkml.org/lkml/2009/5/30/177 )
dev_addr_init() incorrectly uses sizeof() operator. We were
initializing one byte instead of MAX_ADDR_LEN bytes.
Reported-by: Vegard Nossum <vegard.nossum@gmail.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
NETDEV_UP is called after the device is set UP, but sometimes
it is useful to be able to veto the device UP. Introduce a
new NETDEV_PRE_UP notifier that can be used for exactly this.
The first use case will be cfg80211 denying interfaces to be
set UP if the device is known to be rfkill'ed.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Define three accessors to get/set dst attached to a skb
struct dst_entry *skb_dst(const struct sk_buff *skb)
void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;
Delete skb->dst field
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch converts unicast address list to standard list_head using
previously introduced struct netdev_hw_addr. It also relaxes the
locking. Original spinlock (still used for multicast addresses) is not
needed and is no longer used for a protection of this list. All
reading and writing takes place under rtnl (with no changes).
I also removed a possibility to specify the length of the address
while adding or deleting unicast address. It's always dev->addr_len.
The convertion touched especially e1000 and ixgbe codes when the
change is not so trivial.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
drivers/net/bnx2.c | 13 +--
drivers/net/e1000/e1000_main.c | 24 +++--
drivers/net/ixgbe/ixgbe_common.c | 14 ++--
drivers/net/ixgbe/ixgbe_common.h | 4 +-
drivers/net/ixgbe/ixgbe_main.c | 6 +-
drivers/net/ixgbe/ixgbe_type.h | 4 +-
drivers/net/macvlan.c | 11 +-
drivers/net/mv643xx_eth.c | 11 +-
drivers/net/niu.c | 7 +-
drivers/net/virtio_net.c | 7 +-
drivers/s390/net/qeth_l2_main.c | 6 +-
drivers/scsi/fcoe/fcoe.c | 16 ++--
include/linux/netdevice.h | 18 ++--
net/8021q/vlan.c | 4 +-
net/8021q/vlan_dev.c | 10 +-
net/core/dev.c | 195 +++++++++++++++++++++++++++-----------
net/dsa/slave.c | 10 +-
net/packet/af_packet.c | 4 +-
18 files changed, 227 insertions(+), 137 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
Use ALIGN() and PTR_ALIGN() macros instead of handcoding them.
Get rid of NETDEV_ALIGN_CONST ugly define
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
As we know the only packets which need the final pskb_may_pull
are completely non-linear, and have all the required bits in
frag0, we can perform a straight memcpy instead of going through
pskb_may_pull and doing skb_copy_bits.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
For the overwhelming majority of cases, skb_gro_header's return
value cannot be NULL. Yet we must check it because of its current
form. This patch splits it up into multiple functions in order
to avoid this.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
By caching frag0_len, we can avoid checking both frag0 and the
length separately in skb_gro_header. This helps as skb_gro_header
is called four times per packet which amounts to a few million
times at 10Gb/s.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently skb_gro_header is used for packets which put the hardware
header in skb->data with the rest in frags. Since the drivers that
need this optimisation all provide completely non-linear packets,
we can gain extra optimisations by only performing the frag0
optimisation for completely non-linear packets.
In particular, we can simply test frag0 (instead of skb_headlen)
to see whether the optimisation is in force.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The function skb_gro_header is called four times per packet which
quickly adds up at 10Gb/s. This patch inlines it to allow better
optimisations.
Some architectures perform multiplication for page_address, which
is done by each skb_gro_header invocation. This patch caches that
value in skb->cb to avoid the unnecessary multiplications.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We would like to get rid of netdev->trans_start = jiffies; that about all net
drivers have to use in their start_xmit() function, and use txq->trans_start
instead.
This can be done generically in core network, as suggested by David.
Some devices, (particularly loopback) dont need trans_start update, because
they dont have transmit watchdog. We could add a new device flag, or rely
on fact that txq->tran_start can be updated is txq->xmit_lock_owner is
different than -1. Use a helper function to hide our choice.
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
All drivers are already converted to new net_device_ops API
and nobody uses old API anymore.
Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch to add the ability to detect drops in hardware interfaces via dropwatch.
Adds a tracepoint to net_rx_action to signal everytime a napi instance is
polled. The dropmon code then periodically checks to see if the rx_frames
counter has changed, and if so, adds a drop notification to the netlink
protocol, using the reserved all-0's vector to indicate the drop location was in
hardware, rather than somewhere in the code.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
include/linux/net_dropmon.h | 8 ++
include/trace/napi.h | 11 +++
net/core/dev.c | 5 +
net/core/drop_monitor.c | 124 ++++++++++++++++++++++++++++++++++++++++++--
net/core/net-traces.c | 4 +
net/core/netpoll.c | 2
6 files changed, 149 insertions(+), 5 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
One point of contention in high network loads is the dst_release() performed
when a transmited skb is freed. This is because NIC tx completion calls
dev_kree_skb() long after original call to dev_queue_xmit(skb).
CPU cache is cold and the atomic op in dst_release() stalls. On SMP, this is
quite visible if one CPU is 100% handling softirqs for a network device,
since dst_clone() is done by other cpus, involving cache line ping pongs.
It seems right place to release dst is in dev_hard_start_xmit(), for most
devices but ones that are virtual, and some exceptions.
David Miller suggested to define a new device flag, set in alloc_netdev_mq()
(so that most devices set it at init time), and carefuly unset in devices
which dont want a NULL skb->dst in their ndo_start_xmit().
List of devices that must clear this flag is :
- loopback device, because it calls netif_rx() and quoting Patrick :
"ip_route_input() doesn't accept loopback addresses, so loopback packets
already need to have a dst_entry attached."
- appletalk/ipddp.c : needs skb->dst in its xmit function
- And all devices that call again dev_queue_xmit() from their xmit function
(as some classifiers need skb->dst) : bonding, vlan, macvlan, eql, ifb, hdlc_fr
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
offsetof(struct net_device, features)=0x44
offsetof(struct net_device, stats.tx_packets)=0x54
offsetof(struct net_device, stats.tx_bytes)=0x5c
offsetof(struct net_device, stats.tx_dropped)=0x6c
Network drivers that touch dev->stats.tx_packets/stats.tx_bytes in their
tx path can slow down SMP operations, since they dirty a cache line
that should stay shared (dev->features is needed in rx and tx paths)
We could move away stats field in net_device but it wont help that much.
(Two cache lines dirtied in tx path, we can do one only)
Better solution is to add tx_packets/tx_bytes/tx_dropped in struct
netdev_queue because this structure is already touched in tx path and
counters updates will then be free (no increase in size)
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add missed checking of dev_addr_init return value in alloc_netdev_mq.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
net/core/dev.c | 15 ++++++++++++---
1 files changed, 12 insertions(+), 3 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>
v5 -> v6 (current):
-removed so far unused static functions
-corrected dev_addr_del_multiple to call del instead of add
v4 -> v5:
-added device address type (suggested by davem)
-removed refcounting (better to have simplier code then safe potentially few
bytes)
v3 -> v4:
-changed kzalloc to kmalloc in __hw_addr_add_ii()
-ASSERT_RTNL() avoided in dev_addr_flush() and dev_addr_init()
v2 -> v3:
-removed unnecessary rcu read locking
-moved dev_addr_flush() calling to ensure no null dereference of dev_addr
v1 -> v2:
-added forgotten ASSERT_RTNL to dev_addr_init and dev_addr_flush
-removed unnecessary rcu_read locking in dev_addr_init
-use compare_ether_addr_64bits instead of compare_ether_addr
-use L1_CACHE_BYTES as size for allocating struct netdev_hw_addr
-use call_rcu instead of rcu_synchronize
-moved is_etherdev_addr into __KERNEL__ ifdef
This patch introduces a new list in struct net_device and brings a set of
functions to handle the work with device address list. The list is a replacement
for the original dev_addr field and because in some situations there is need to
carry several device addresses with the net device. To be backward compatible,
dev_addr is made to point to the first member of the list so original drivers
sees no difference.
Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based almost entirely upon a patch by Eric Dumazet.
The common case is to have num-tx-queues <= num_rx_queues
and even if num_tx_queues is larger it will not be significantly
larger.
Therefore, a subtraction loop is always going to be faster than
modulus.
Signed-off-by: David S. Miller <davem@davemloft.net>
When skb_rx_queue_recorded() is true, we dont want to use jash distribution
as the device driver exactly told us which queue was selected at RX time.
jhash makes a statistical shuffle, but this wont work with 8 static inputs.
Later improvements would be to compute reciprocal value of real_num_tx_queues
to avoid a divide here. But this computation should be done once,
when real_num_tx_queues is set. This needs a separate patch, and a new
field in struct net_device.
Reported-by: Andrew Dickinson <andrew@whydna.net>
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The skb_gro_* code fails to handle the case where a header starts
in the linear area but ends in the frags area. Since the goal
of skb_gro_* is to optimise the case of completely non-linear
packets, we can simply bail out if we have anything in the linear
area.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This loop over fragments in napi_fraginfo_skb() was "interesting".
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alex Sidorenko reported:
"while experimenting with 'netem' we have found some strange behaviour. It
seemed that ingress delay as measured by 'ping' command shows up on some
hosts but not on others.
After some investigation I have found that the problem is that skbuff->tstamp
field value depends on whether there are any packet sniffers enabled. That
is:
- if any ptype_all handler is registered, the tstamp field is as expected
- if there are no ptype_all handlers, the tstamp field does not show the delay"
This patch prevents unnecessary update of tstamp in dev_queue_xmit_nit()
on ingress path (with act_mirred) adding a check, so minimal overhead on
the fast path, but only when sniffers etc. are active.
Since netem at ingress seems to logically emulate a network before a host,
tstamp is zeroed to trigger the update and pretend delays are from the
outside.
Reported-by: Alex Sidorenko <alexandre.sidorenko@hp.com>
Tested-by: Alex Sidorenko <alexandre.sidorenko@hp.com>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
It turns out that copying a 16-byte area at ~800k times a second
can be really expensive :) This patch redesigns the frags GRO
interface to avoid copying that area twice.
The two disciples of the frags interface have been converted.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Since everybody has been focusing on baremetal GRO performance
no one noticed when I added a bug that zapped gso_size for all
GRO packets. This only gets picked up when you forward the skb
out of an interface.
Thanks to Mark Wagner for noticing this bug when testing kvm.
Reported-by: Mark Wagner <mwagner@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently netif_device_attach/detach are only stopping one queue. They
should be starting and stopping all the queues on a given device.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
GRO assumes that there is a one-to-one relationship between NAPI
structure and network device. Some devices like sky2 share multiple
devices on a single interrupt so only have one NAPI handler. Rather than
split GRO from NAPI, just have GRO assume if device changes that
it is a different flow.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When I fixed the GRO crash in the legacy receive path I used
napi_complete to replace __napi_complete. Unfortunately they're
not the same when NETPOLL is enabled, which may result in us
not calling __napi_complete at all.
What's more, we really do need to keep the __napi_complete call
within the IRQ-off section since in theory an IRQ can occur in
between and fill up the backlog to the maximum, causing us to
lock up.
Since we can't seem to find a fix that works properly right now,
this patch reverts all the GRO support from the netif_rx path.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no gain using prefetch() in dev_hard_start_xmit(), since
we already had to read ops->ndo_select_queue pointer in dev_pick_tx(),
and both pointers are probably located in the same cache line.
This prefetch call slows down fast path because of a stall in address
computation.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Some minor changes to queue hashing:
1. Use const on accessor functions
2. Export skb_tx_hash for use in drivers (see ixgbe)
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
struct sk_buff pointers should be freed with kfree_skb.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
On the legacy netif_rx path, I incorrectly tried to optimise
the napi_complete call by using __napi_complete before we reenable
IRQs. This simply doesn't work since we need to flush the held
GRO packets first.
This patch fixes it by doing the obvious thing of reenabling
IRQs first and then calling napi_complete.
Reported-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As my netpoll fix for net doesn't really work for net-next, we
need this update to move the checks into the right place. As it
stands we may pass freed skbs to netpoll_receive_skb.
This patch also introduces a netpoll_rx_on function to avoid GRO
completely if we're invoked through netpoll. This might seem
paranoid but as netpoll may have an external receive hook it's
better to be safe than sorry. I don't think we need this for
2.6.29 though since there's nothing immediately broken by it.
This patch also moves the GRO_* return values to netdevice.h since
VLAN needs them too (I tried to avoid this originally but alas
this seems to be the easiest way out). This fixes a bug in VLAN
where it continued to use the old return value 2 instead of the
correct GRO_DROP.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add FC CRC offload check for ETH_P_FCOE.
Signed-off-by: Yi Zou <yi.zou@intel.com>
Acked-by: David Miller <davem@davemloft.net>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
As analyzed by Patrick McHardy, vlan needs to reset it's
netdev_ops pointer in it's ->init() function but this
leaves the compat method pointers stale.
Add a netdev_resync_ops() and call it from the vlan code.
Any other driver which changes ->netdev_ops after register_netdevice()
will need to call this new function after doing so too.
With help from Patrick McHardy.
Tested-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
It turns out that net_alive is unnecessary, and the original problem
that led to it being added was simply that the icmp code thought
it was a network device and wound up being unable to handle packets
while there were still packets in the network namespace.
Now that icmp and tcp have been fixed to properly register themselves
this problem is no longer present and we have a stronger guarantee
that packets will not arrive in a network namespace then that provided
by net_alive in netif_receive_skb. So remove net_alive allowing
packet reception run a little faster.
Additionally document the strong reason why network namespace cleanup
is safe so that if something happens again someone else will have
a chance of figuring it out.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The netpoll entry checks are required to ensure that we don't
receive normal packets when invoked via netpoll. Unfortunately
it only ever worked for the netif_receive_skb/netif_rx entry
points. The VLAN (and subsequently GRO) entry point didn't
have the check and therefore can trigger all sorts of weird
problems.
This patch adds the netpoll check to all entry points.
I'm still uneasy with receiving at all under netpoll (which
apparently is only used by the out-of-tree kdump code). The
reason is it is perfectly legal to receive all data including
headers into highmem if netpoll is off, but if you try to do
that with netpoll on and someone gets a printk in an IRQ handler
you're going to get a nice BUG_ON.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
It turns out that net_alive is unnecessary, and the original problem
that led to it being added was simply that the icmp code thought
it was a network device and wound up being unable to handle packets
while there were still packets in the network namespace.
Now that icmp and tcp have been fixed to properly register themselves
this problem is no longer present and we have a stronger guarantee
that packets will not arrive in a network namespace then that provided
by net_alive in netif_receive_skb. So remove net_alive allowing
packet reception run a little faster.
Additionally document the strong reason why network namespace cleanup
is safe so that if something happens again someone else will have
a chance of figuring it out.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The current implementation of the TX software time stamping fallback is
faulty because it accesses the skb after ndo_start_xmit() returns
successfully. This patch removes the fallback, which fixes kernel panics
seen during stress tests. Hardware time stamping is not affected by this
removal.
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Optimize skb_tx_hash() by eliminating a comparison that executes for
every packet. skb_tx_hashrnd initialization is moved to a later part of
the startup sequence, namely after the "random" driver is initialized.
Rebooted the system three times and verified that the code generates
different random numbers each time.
Signed-off-by: Krishna Kumar <krkumar2@in.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The additional per-packet information (16 bytes for time stamps, 1
byte for flags) is stored for all packets in the skb_shared_info
struct. This implementation detail is hidden from users of that
information via skb_* accessor functions. A separate struct resp.
union is used for the additional information so that it can be
stored/copied easily outside of skb_shared_info.
Compared to previous implementations (reusing the tstamp field
depending on the context, optional additional structures) this
is the simplest solution. It does not extend sk_buff itself.
TX time stamping is implemented in software if the device driver
doesn't support hardware time stamping.
The new semantic for hardware/software time stamping around
ndo_start_xmit() is based on two assumptions about existing
network device drivers which don't support hardware time
stamping and know nothing about it:
- they leave the new skb_shared_tx unmodified
- the keep the connection to the originating socket in skb->sk
alive, i.e., don't call skb_orphan()
Given that skb_shared_tx is new, the first assumption is safe.
The second is only true for some drivers. As a result, software
TX time stamping currently works with the bnx2 driver, but not
with the unmodified igb driver (the two drivers this patch series
was tested with).
Signed-off-by: Patrick Ohly <patrick.ohly@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch optimises the Ethernet header comparison to use 2-byte
and 4-byte xors instead of memcmp. In order to facilitate this,
the actual comparison is now carried out by the callers of the
shared dev_gro_receive function.
This has a significant impact when receiving 1500B packets through
10GbE.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch prepares for the move of the same_flow checks out of
dev_gro_receive. As such we need to remember the number of held
packets since doing a loop just to count them every time is silly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Based upon a patch from Atsushi Nemoto <anemo@mba.ocn.ne.jp>
--------------------
The commit 649274d993 ("net_dma:
acquire/release dma channels on ifup/ifdown") added unconditional call
of dmaengine_get() to net_dma. The API should be called only if
NET_DMA was enabled.
--------------------
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Dan Williams <dan.j.williams@intel.com>
The previous fix ad0f990444 (gro:
Fix handling of imprecisely split packets) only fixed the case
of frags merging, frag_list merging in the same circumstances
were still broken.
In particular, the packet headers end up in the data stream.
This patch fixes this plus another issue where an imprecisely
split packet header may be read incorrectly (this is mostly
harmless since it'll simply cause the packet to not match and
be rejected for GRO).
Thanks to Emil Tantilov and Jeff Kirsher for helping to track
this down.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As it currently stands, skb destructors are forbidden on the
receive path because the protocol end-points will overwrite
any existing destructor with their own.
This is the reason why we have to call skb_orphan in the loopback
driver before we reinject the packet back into the stack, thus
creating a period during which loopback traffic isn't charged
to any socket.
With virtualisation, we have a similar problem in that traffic
is reinjected into the stack without being associated with any
socket entity, thus providing no natural congestion push-back
for those poor folks still stuck with UDP.
Now had we been consistent in telling them that UDP simply has
no congestion feedback, I could just fob them off. Unfortunately,
we appear to have gone to some length in catering for this on
the standard UDP path, with skb/socket accounting so that has
created a very unhealthy dependency.
Alas habits are difficult to break out of, so we may just have
to allow skb destructors on the receive path.
It turns out that making skb destructors useable on the receive path
isn't as easy as it seems. For instance, simply adding skb_orphan
to skb_set_owner_r isn't enough. This is because we assume all
over the IP stack that skb->sk is an IP socket if present.
The new transparent proxy code goes one step further and assumes
that skb->sk is the receiving socket if present.
Now all of this can be dealt with by adding simple checks such
as only treating skb->sk as an IP socket if skb->sk->sk_family
matches. However, it turns out that for bridging at least we
don't need to do all of this work.
This is of interest because most virtualisation setups use bridging
so we don't actually go through the IP stack on the host (with
the exception of our old nemesis the bridge netfilter, but that's
easily taken care of).
So this patch simply adds skb_orphan to the point just before we
enter the IP stack, but after we've gone through the bridge on the
receive path. It also adds an skb_orphan to the one place in
netfilter that touches skb->sk/skb->destructor, that is, tproxy.
One word of caution, because of the internal code structure, anyone
wishing to deploy this must use skb_set_owner_w as opposed to
skb_set_owner_r since many functions that create a new skb from
an existing one will invoke skb_set_owner_w on the new skb.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The commit 89a1b249edcf9be884e71f92df84d48355c576aa (gro: Avoid
copying headers of unmerged packets) only worked for packets
which are either completely linear, completely non-linear, or
packets which exactly split at the boundary between headers and
payload.
Anything else would cause bits in the header to go missing if
the packet is held by GRO.
This may have broken drivers such as ixgbe.
This patch fixes the places that assumed or only worked with
the above cases.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch optimises napi_fraginfo_skb to only copy the bits
necessary. We also open-code the memcpy so that the alignment
information is always available to gcc.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Unfortunately simplicity isn't always the best. The fraginfo
interface turned out to be suboptimal. The problem was quite
obvious. For every packet, we have to copy the headers from
the frags structure into skb->head, even though for 99% of the
packets this part is immediately thrown away after the merge.
LRO didn't have this problem because it directly read the headers
from the frags structure.
This patch attempts to address this by creating an interface
that allows GRO to access the headers in the first frag without
having to copy it. Because all drivers that use frags place the
headers in the first frag this optimisation should be enough.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently VLAN still has a bit of common code handling the aftermath
of GRO that's shared with the common path. This patch moves them
into shared helpers to reduce code duplication.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We now only TX hash on pre-computed SKB properties.
The thinking is:
1) High performance routing and firewalling setups will
have a multiqueue capable card used for receive, and
therefore would have RX queue recordings made into
the SKB which can be used for the TX side hash.
2) Locally generated packets will have an attached socket
and thus a valid sk->sk_hash to make use of.
Signed-off-by: David S. Miller <davem@davemloft.net>
The idea is that drivers which implement multiqueue RX
pre-seed the SKB by recording the RX queue selected by
the hardware.
If such a seed is found on TX, we'll use that to select
the outgoing TX queue.
This helps get more consistent load balancing on router
and firewall loads.
Signed-off-by: David S. Miller <davem@davemloft.net>
When a frag is shorter than an Ethernet header, we'd return a
zeroed packet instead of aborting. This patch fixes that.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
I'm trying to track down why people're hitting the checksum warning
in skb_gso_segment. As the problem seems to be hitting lots of
people and I can't reproduce it or locate the bug, here is a patch
to print out more details which hopefully should help us to track
this down.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This adds an init_dummy_netdev() function that gets a network device
structure (allocation and lifetime entirely under caller's control) and
initialize the minimum amount of fields so it can be used to schedule
NAPI polls without registering a full blown interface. This is to be
used by drivers that need to tie several hardware interfaces to a single
NAPI poll scheduler due to HW limitations.
It also updates the ibm_newemac driver to use that, this fixing the
oops on 2.6.29 due to passing NULL as "dev" to netif_napi_add()
Symbol is exported GPL only a I don't think we want binary drivers doing
that sort of acrobatics (if we want them at all).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When an skb with page frags is merged into an existing one, we
cannibalise its reference count. This is OK when the skb is
reused because we set nr_frags to zero in that case. However,
for the case where the skb is freed through kfree_skb, we didn't
clear nr_frags which causes the page to be freed prematurely.
This is fixed by moving the skb resetting into skb_gro_receive.
Reported-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As GRO cannot be applied to packets with frag_list we need to
make sure that we reject such packets if they are fed to us,
e.g., through a tunnel device.
Also there is no point in applying GRO on GSO packets so they
too should be rejected. This allows GRO to be used in virtio-net
which may produce GSO packets directly but may still benefit
from GRO if the other end of it doesn't support GSO.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The recent dmaengine rework removed the capability to remove dma device
driver modules while net_dma is active. Rather than notify
dmaengine-clients that channels are trying to be removed, we now rely on
clients to notify dmaengine when they no longer have a need for
channels. Teach net_dma to release channels by taking dmaengine
references at netdevice open and dropping references at netdevice close.
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (22 commits)
ioat: fix self test for multi-channel case
dmaengine: bump initcall level to arch_initcall
dmaengine: advertise all channels on a device to dma_filter_fn
dmaengine: use idr for registering dma device numbers
dmaengine: add a release for dma class devices and dependent infrastructure
ioat: do not perform removal actions at shutdown
iop-adma: enable module removal
iop-adma: kill debug BUG_ON
iop-adma: let devm do its job, don't duplicate free
dmaengine: kill enum dma_state_client
dmaengine: remove 'bigref' infrastructure
dmaengine: kill struct dma_client and supporting infrastructure
dmaengine: replace dma_async_client_register with dmaengine_get
atmel-mci: convert to dma_request_channel and down-level dma_slave
dmatest: convert to dma_request_channel
dmaengine: introduce dma_request_channel and private channels
net_dma: convert to dma_find_channel
dmaengine: provide a common 'issue_pending_all' implementation
dmaengine: centralize channel allocation, introduce dma_find_channel
dmaengine: up-level reference counting to the module level
...
Previously GRO's only entry point from the outside is through
napi_gro_receive and napi_gro_frags. These interfaces are for
device drivers.
This patch rearranges things to provide a new set of interfaces
for VLANs. These interfaces are for internal use only. The
VLAN code itself can then provide a set of entry points for
device drivers.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
All users have been converted to either the general-purpose allocator,
dma_find_channel, or dma_request_channel.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Now that clients no longer need to be notified of channel arrival
dma_async_client_register can simply increment the dmaengine_ref_count.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Use the general-purpose channel allocation provided by dmaengine.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
async_tx and net_dma each have open-coded versions of issue_pending_all,
so provide a common routine in dmaengine.
The implementation needs to walk the global device list, so implement
rcu to allow dma_issue_pending_all to run lockless. Clients protect
themselves from channel removal events by holding a dmaengine reference.
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch allows GRO to merge page frags (skb_shinfo(skb)->frags)
in one skb, rather than using the less efficient frag_list.
It also adds a new interface, napi_gro_frags to allow drivers
to inject page frags directly into the stack without allocating
an skb. This is intended to be the GRO equivalent for LRO's
lro_receive_frags interface.
The existing GSO interface can already handle page frags with
or without an appended frag_list so nothing needs to be changed
there.
The merging itself is rather simple. We store any new frag entries
after the last existing entry, without checking whether the first
new entry can be merged with the last existing entry. Making this
check would actually be easy but since no existing driver can
produce contiguous frags anyway it would just be mental masturbation.
If the total number of entries would exceed the capacity of a
single skb, we simply resort to using frag_list as we do now.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
In order to allow GRO packets without frag_list at all, we need to
store the MSS in the packet itself. The obvious place is gso_size.
The only thing to watch out for is if the packet ends up not being
GRO then we need to clear gso_size before pushing the packet into
the stack.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
During network namespace teardown we either move or delete
all of the network devices associated with a network namespace.
In the case of veth devices deleting one will also delete it's
pair device. If both devices are in the same network namespace
then for_each_netdev_safe is insufficient as next may point
to the second veth device we have deleted.
To avoid problems I do what we do in __rtnl_kill_links and
restart the scan of the device list, after we have deleted
a device.
Currently dev_change_netnamespace does not appear to suffer from
this problem, but wireless devices are also paired and likely
should be moved between network namespaces together. So I have
errored on the side of caution and restart the scan of the network
devices in that case as well.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1429 commits)
net: Allow dependancies of FDDI & Tokenring to be modular.
igb: Fix build warning when DCA is disabled.
net: Fix warning fallout from recent NAPI interface changes.
gro: Fix potential use after free
sfc: If AN is enabled, always read speed/duplex from the AN advertising bits
sfc: When disabling the NIC, close the device rather than unregistering it
sfc: SFT9001: Add cable diagnostics
sfc: Add support for multiple PHY self-tests
sfc: Merge top-level functions for self-tests
sfc: Clean up PHY mode management in loopback self-test
sfc: Fix unreliable link detection in some loopback modes
sfc: Generate unique names for per-NIC workqueues
802.3ad: use standard ethhdr instead of ad_header
802.3ad: generalize out mac address initializer
802.3ad: initialize ports LACPDU from const initializer
802.3ad: remove typedef around ad_system
802.3ad: turn ports is_individual into a bool
802.3ad: turn ports is_enabled into a bool
802.3ad: make ntt bool
ixgbe: Fix set_ringparam in ixgbe to use the same memory pools.
...
Fixed trivial IPv4/6 address printing conflicts in fs/cifs/connect.c due
to the conversion to %pI (in this networking merge) and the addition of
doing IPv6 addresses (from the earlier merge of CIFS).
The initial skb may have been freed after napi_gro_complete in
napi_gro_receive if it was merged into an existing packet. Thus
we cannot check same_flow (which indicates whether it was merged)
after calling napi_gro_complete.
This patch fixes this by saving the same_flow status before the
call to napi_gro_complete.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The recent GRO patches introduced the NAPI removal of devices in
free_netdev. For drivers that can change the number of queues during
driver operation, the NAPI infrastructure doesn't allow the freeing and
re-addition of NAPI entities without reloading the driver.
This change reinitializes the dev_list in each NAPI struct on delete,
instead of just deleting it (and assigning the list pointers to POISON).
Drivers that wish to remove/re-add NAPI will need to re-initialize the
netdev napi_list after removing all NAPI instances, before re-adding NAPI
devices again.
Signed-off-by: Peter P Waskiewicz Jr <peter.p.waskiewicz.jr@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A command like this: "brctl addif br1 eth1" issued as a user gave me
an oops when bridge module wasn't loaded. It's caused by using a dev
pointer before checking for NULL.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
A separate xmit lock class supports GPRS over a Phonet pipe over a TUN
device (type ARPHRD_NONE).
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also leave some room for more 802.11 types.
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds the top-level GRO (Generic Receive Offload) infrastructure.
This is pretty similar to LRO except that this is protocol-independent.
Instead of holding packets in an lro_mgr structure, they're now held in
napi_struct.
For drivers that intend to use this, they can set the NETIF_F_GRO bit and
call napi_gro_receive instead of netif_receive_skb or just call netif_rx.
The latter will call napi_receive_skb automatically. When napi_gro_receive
is used, the driver must either call napi_complete/napi_rx_complete, or
call napi_gro_flush in softirq context if the driver uses the primitives
__napi_complete/__napi_rx_complete.
Protocols will set the gro_receive and gro_complete function pointers in
order to participate in this scheme.
In addition to the packet, gro_receive will get a list of currently held
packets. Each packet in the list has a same_flow field which is non-zero
if it is a potential match for the new packet. For each packet that may
match, they also have a flush field which is non-zero if the held packet
must not be merged with the new packet.
Once gro_receive has determined that the new skb matches a held packet,
the held packet may be processed immediately if the new skb cannot be
merged with it. In this case gro_receive should return the pointer to
the existing skb in gro_list. Otherwise the new skb should be merged into
the existing packet and NULL should be returned, unless the new skb makes
it impossible for any further merges to be made (e.g., FIN packet) where
the merged skb should be returned.
Whenever the skb is merged into an existing entry, the gro_receive
function should set NAPI_GRO_CB(skb)->same_flow. Note that if an skb
merely matches an existing entry but can't be merged with it, then
this shouldn't be set.
If gro_receive finds it pointless to hold the new skb for future merging,
it should set NAPI_GRO_CB(skb)->flush.
Held packets will be flushed by napi_gro_flush which is called by
napi_complete and napi_rx_complete.
Currently held packets are stored in a singly liked list just like LRO.
The list is limited to a maximum of 8 entries. In future, this may be
expanded to use a hash table to allow more flows to be held for merging.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
