Commit Graph

5455 Commits

Author SHA1 Message Date
John W. Linville
01e17dacd4 Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Conflicts:
	drivers/net/wireless/mac80211_hwsim.c
2012-08-21 16:00:21 -04:00
Johannes Berg
6d71117a27 mac80211: add IEEE80211_HW_P2P_DEV_ADDR_FOR_INTF
Some devices like the current iwlwifi implementation
require that the P2P interface address match the P2P
Device address (only one P2P interface is supported.)
Add the HW flag IEEE80211_HW_P2P_DEV_ADDR_FOR_INTF
that allows drivers to request that P2P Interfaces
added while a P2P Device is active get the same MAC
address by default.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 13:58:23 +02:00
Johannes Berg
98104fdeda cfg80211: add P2P Device abstraction
In order to support using a different MAC address
for the P2P Device address we must first have a
P2P Device abstraction that can be assigned a MAC
address.

This abstraction will also be useful to support
offloading P2P operations to the device, e.g.
periodic listen for discoverability.

Currently, the driver is responsible for assigning
a MAC address to the P2P Device, but this could be
changed by allowing a MAC address to be given to
the NEW_INTERFACE command.

As it has no associated netdev, a P2P Device can
only be identified by its wdev identifier but the
previous patches allowed using the wdev identifier
in various APIs, e.g. remain-on-channel.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 13:58:21 +02:00
Johannes Berg
4c29867790 mac80211: support A-MPDU status reporting
Support getting A-MPDU status information from the
drivers and reporting it to userspace via radiotap
in the standard fields.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 13:53:22 +02:00
Johannes Berg
48613ece3d wireless: add radiotap A-MPDU status field
Define the A-MPDU status field in radiotap, also
update the radiotap parser for it and the MCS field
that was apparently missed last time.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 13:53:09 +02:00
Antonio Quartulli
e687f61eed mac80211: add supported rates change notification in IBSS
In IBSS it is possible that the supported rates set for a station changes over
time (e.g. it gets first initialised as an empty set because of no available
information about rates and updated later). In this case the driver has to be
notified about the change in order to update its internal table accordingly (if
needed).

This behaviour is needed by all those drivers that handle rc internally but
leave stations management to mac80211

Reported-by: Gui Iribarren <gui@altermundi.net>
Signed-off-by: Antonio Quartulli <ordex@autistici.org>
[Johannes - add docs, validate IBSS mode only, fix compilation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 13:31:43 +02:00
John W. Linville
57f784fed3 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next 2012-08-10 15:13:12 -04:00
Andre Guedes
b9b343d254 Bluetooth: Fix hci_le_conn_complete_evt
We need to check the 'Role' parameter from the LE Connection
Complete Event in order to properly set 'out' and 'link_mode'
fields from hci_conn structure.

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:05:10 -03:00
Masatake YAMATO
256a06c8a8 Bluetooth: /proc/net/ entries for bluetooth protocols
lsof command can tell the type of socket processes are using.
Internal lsof uses inode numbers on socket fs to resolve the type of
sockets. Files under /proc/net/, such as tcp, udp, unix, etc provides
such inode information.

Unfortunately bluetooth related protocols don't provide such inode
information. This patch series introduces /proc/net files for the protocols.

This patch against af_bluetooth.c provides facility to the implementation
of protocols. This patch extends bt_sock_list and introduces two exported
function bt_procfs_init, bt_procfs_cleanup.

The type bt_sock_list is already used in some of implementation of
protocols. bt_procfs_init prepare seq_operations which converts
protocol own bt_sock_list data to protocol own proc entry when the
entry is accessed.

What I, lsof user, need is just inode number of bluetooth
socket. However, people may want more information. The bt_procfs_init
takes a function pointer for customizing the show handler of
seq_operations.

In v4 patch, __acquires and __releases attributes are added to suppress
sparse warning. Suggested by Andrei Emeltchenko.

In v5 patch, linux/proc_fs.h is included to use PDE. Build error is
reported by Fengguang Wu.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:58 -03:00
Jaganath Kanakkassery
4af66c691f Bluetooth: Free the l2cap channel list only when refcount is zero
Move the l2cap channel list chan->global_l under the refcnt
protection and free it based on the refcnt.

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
Signed-off-by: Syam Sidhardhan <s.syam@samsung.com>
Reviewed-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:58 -03:00
Jaganath Kanakkassery
3064837289 Bluetooth: Move l2cap_chan_hold/put to l2cap_core.c
Refactor the code in order to use the l2cap_chan_destroy()
from l2cap_chan_put() under the refcnt protection.

Signed-off-by: Jaganath Kanakkassery <jaganath.k@samsung.com>
Signed-off-by: Syam Sidhardhan <s.syam@samsung.com>
Reviewed-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:58 -03:00
Andrei Emeltchenko
9e66463127 Bluetooth: Make connect / disconnect cfm functions return void
Return values are never used because callers hci_proto_connect_cfm
and hci_proto_disconn_cfm return void.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:58 -03:00
Andrei Emeltchenko
ab846ec4ea Bluetooth: Define AMP controller statuses
AMP status codes copied from Bluez patch sent by Peter Krystad
<pkrystad@codeaurora.org>.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:55 -03:00
Andrei Emeltchenko
b93a68295f Bluetooth: trivial: Fix mixing spaces and tabs in smp
Change spaces to tabs in smp code

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:55 -03:00
Andrei Emeltchenko
71becf0cea Bluetooth: debug: Fix printing refcnt for hci_conn
Use the same style for refcnt printing through all Bluetooth code
taking the reference the l2cap_chan refcnt printing.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:55 -03:00
Andrei Emeltchenko
bb4b2a9ae3 Bluetooth: mgmt: Managing only BR/EDR HCI controllers
Add check that HCI controller is BR/EDR. AMP controller shall not be
managed by mgmt interface and consequently user space.

Signed-off-by: Andrei Emeltchenko <andrei.emeltchenko@intel.com>
Acked-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:54 -03:00
Andre Guedes
3f1732462c Bluetooth: Remove missing code
This patch removes the struct adv_entry since it is not used anymore.
This struct should have been removed in commit 479453d (Bluetooth:
Remove advertising cache).

Signed-off-by: Andre Guedes <andre.guedes@openbossa.org>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
2012-08-06 15:02:54 -03:00
David S. Miller
caacf05e5a ipv4: Properly purge netdev references on uncached routes.
When a device is unregistered, we have to purge all of the
references to it that may exist in the entire system.

If a route is uncached, we currently have no way of accomplishing
this.

So create a global list that is scanned when a network device goes
down.  This mirrors the logic in net/core/dst.c's dst_ifdown().

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31 15:06:50 -07:00
David S. Miller
c5038a8327 ipv4: Cache routes in nexthop exception entries.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31 15:02:02 -07:00
Eric Dumazet
d26b3a7c4b ipv4: percpu nh_rth_output cache
Input path is mostly run under RCU and doesnt touch dst refcnt

But output path on forwarding or UDP workloads hits
badly dst refcount, and we have lot of false sharing, for example
in ipv4_mtu() when reading rt->rt_pmtu

Using a percpu cache for nh_rth_output gives a nice performance
increase at a small cost.

24 udpflood test on my 24 cpu machine (dummy0 output device)
(each process sends 1.000.000 udp frames, 24 processes are started)

before : 5.24 s
after : 2.06 s
For reference, time on linux-3.5 : 6.60 s

Signed-off-by: Eric Dumazet <edumazet@google.com>
Tested-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31 14:41:39 -07:00
Eric Dumazet
54764bb647 ipv4: Restore old dst_free() behavior.
commit 404e0a8b6a (net: ipv4: fix RCU races on dst refcounts) tried
to solve a race but added a problem at device/fib dismantle time :

We really want to call dst_free() as soon as possible, even if sockets
still have dst in their cache.
dst_release() calls in free_fib_info_rcu() are not welcomed.

Root of the problem was that now we also cache output routes (in
nh_rth_output), we must use call_rcu() instead of call_rcu_bh() in
rt_free(), because output route lookups are done in process context.

Based on feedback and initial patch from David Miller (adding another
call_rcu_bh() call in fib, but it appears it was not the right fix)

I left the inet_sk_rx_dst_set() helper and added __rcu attributes
to nh_rth_output and nh_rth_input to better document what is going on in
this code.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-31 14:41:38 -07:00
Thomas Huehn
36323f817a mac80211: move TX station pointer and restructure TX
Remove the control.sta pointer from ieee80211_tx_info to free up
sufficient space in the TX skb control buffer for the upcoming
Transmit Power Control (TPC).
Instead, the pointer is now on the stack in a new control struct
that is passed as a function parameter to the drivers' tx method.

Signed-off-by: Thomas Huehn <thomas@net.t-labs.tu-berlin.de>
Signed-off-by: Alina Friedrichsen <x-alina@gmx.net>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[reworded commit message]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-31 16:18:39 +02:00
Eliad Peller
ab09587740 mac80211: add PS flag to bss_conf
Currently, ps mode is indicated per device (rather than
per interface), which doesn't make a lot of sense.

Moreover, there are subtle bugs caused by the inability
to indicate ps change along with other changes
(e.g. when the AP deauth us, we'd like to indicate
CHANGED_PS | CHANGED_ASSOC, as changing PS before
notifying about disassociation will result in null-packets
being sent (if IEEE80211_HW_SUPPORTS_DYNAMIC_PS) while
the sta is already disconnected.)

Keep the current per-device notifications, and add
parallel per-vif notifications.

In order to keep it simple, the per-device ps and
the per-vif ps are orthogonal - the per-vif ps
configuration is determined only by the user
configuration (enable/disable) and the connection
state, and is not affected by other vifs state and
(temporary) dynamic_ps/offchannel operations
(unlike per-device ps).

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-31 16:11:04 +02:00
Eric Dumazet
0c7462a235 ipv4: remove rt_cache_rebuild_count
After IP route cache removal, rt_cache_rebuild_count is no longer
used.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-30 14:53:22 -07:00
Eric Dumazet
404e0a8b6a net: ipv4: fix RCU races on dst refcounts
commit c6cffba4ff (ipv4: Fix input route performance regression.)
added various fatal races with dst refcounts.

crashes happen on tcp workloads if routes are added/deleted at the same
time.

The dst_free() calls from free_fib_info_rcu() are clearly racy.

We need instead regular dst refcounting (dst_release()) and make
sure dst_release() is aware of RCU grace periods :

Add DST_RCU_FREE flag so that dst_release() respects an RCU grace period
before dst destruction for cached dst

Introduce a new inet_sk_rx_dst_set() helper, using atomic_inc_not_zero()
to make sure we dont increase a zero refcount (On a dst currently
waiting an rcu grace period before destruction)

rt_cache_route() must take a reference on the new cached route, and
release it if was not able to install it.

With this patch, my machines survive various benchmarks.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-30 14:53:22 -07:00
Eric Dumazet
c7109986db ipv6: Early TCP socket demux
This is the IPv6 missing bits for infrastructure added in commit
41063e9dd1 (ipv4: Early TCP socket demux.)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-26 15:50:39 -07:00
David S. Miller
c6cffba4ff ipv4: Fix input route performance regression.
With the routing cache removal we lost the "noref" code paths on
input, and this can kill some routing workloads.

Reinstate the noref path when we hit a cached route in the FIB
nexthops.

With help from Eric Dumazet.

Reported-by: Alexander Duyck <alexander.duyck@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-26 15:50:39 -07:00
Linus Torvalds
3c4cfadef6 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking changes from David S Miller:

 1) Remove the ipv4 routing cache.  Now lookups go directly into the FIB
    trie and use prebuilt routes cached there.

    No more garbage collection, no more rDOS attacks on the routing
    cache.  Instead we now get predictable and consistent performance,
    no matter what the pattern of traffic we service.

    This has been almost 2 years in the making.  Special thanks to
    Julian Anastasov, Eric Dumazet, Steffen Klassert, and others who
    have helped along the way.

    I'm sure that with a change of this magnitude there will be some
    kind of fallout, but such things ought the be simple to fix at this
    point.  Luckily I'm not European so I'll be around all of August to
    fix things :-)

    The major stages of this work here are each fronted by a forced
    merge commit whose commit message contains a top-level description
    of the motivations and implementation issues.

 2) Pre-demux of established ipv4 TCP sockets, saves a route demux on
    input.

 3) TCP SYN/ACK performance tweaks from Eric Dumazet.

 4) Add namespace support for netfilter L4 conntrack helpers, from Gao
    Feng.

 5) Add config mechanism for Energy Efficient Ethernet to ethtool, from
    Yuval Mintz.

 6) Remove quadratic behavior from /proc/net/unix, from Eric Dumazet.

 7) Support for connection tracker helpers in userspace, from Pablo
    Neira Ayuso.

 8) Allow userspace driven TX load balancing functions in TEAM driver,
    from Jiri Pirko.

 9) Kill off NLMSG_PUT and RTA_PUT macros, more gross stuff with
    embedded gotos.

10) TCP Small Queues, essentially minimize the amount of TCP data queued
    up in the packet scheduler layer.  Whereas the existing BQL (Byte
    Queue Limits) limits the pkt_sched --> netdevice queuing levels,
    this controls the TCP --> pkt_sched queueing levels.

    From Eric Dumazet.

11) Reduce the number of get_page/put_page ops done on SKB fragments,
    from Alexander Duyck.

12) Implement protection against blind resets in TCP (RFC 5961), from
    Eric Dumazet.

13) Support the client side of TCP Fast Open, basically the ability to
    send data in the SYN exchange, from Yuchung Cheng.

    Basically, the sender queues up data with a sendmsg() call using
    MSG_FASTOPEN, then they do the connect() which emits the queued up
    fastopen data.

14) Avoid all the problems we get into in TCP when timers or PMTU events
    hit a locked socket.  The TCP Small Queues changes added a
    tcp_release_cb() that allows us to queue work up to the
    release_sock() caller, and that's what we use here too.  From Eric
    Dumazet.

15) Zero copy on TX support for TUN driver, from Michael S. Tsirkin.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1870 commits)
  genetlink: define lockdep_genl_is_held() when CONFIG_LOCKDEP
  r8169: revert "add byte queue limit support".
  ipv4: Change rt->rt_iif encoding.
  net: Make skb->skb_iif always track skb->dev
  ipv4: Prepare for change of rt->rt_iif encoding.
  ipv4: Remove all RTCF_DIRECTSRC handliing.
  ipv4: Really ignore ICMP address requests/replies.
  decnet: Don't set RTCF_DIRECTSRC.
  net/ipv4/ip_vti.c: Fix __rcu warnings detected by sparse.
  ipv4: Remove redundant assignment
  rds: set correct msg_namelen
  openvswitch: potential NULL deref in sample()
  tcp: dont drop MTU reduction indications
  bnx2x: Add new 57840 device IDs
  tcp: avoid oops in tcp_metrics and reset tcpm_stamp
  niu: Change niu_rbr_fill() to use unlikely() to check niu_rbr_add_page() return value
  niu: Fix to check for dma mapping errors.
  net: Fix references to out-of-scope variables in put_cmsg_compat()
  net: ethernet: davinci_emac: add pm_runtime support
  net: ethernet: davinci_emac: Remove unnecessary #include
  ...
2012-07-24 10:01:50 -07:00
David S. Miller
13378cad02 ipv4: Change rt->rt_iif encoding.
On input packet processing, rt->rt_iif will be zero if we should
use skb->dev->ifindex.

Since we access rt->rt_iif consistently via inet_iif(), that is
the only spot whose interpretation have to adjust.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-23 16:36:27 -07:00
David S. Miller
92101b3b2e ipv4: Prepare for change of rt->rt_iif encoding.
Use inet_iif() consistently, and for TCP record the input interface of
cached RX dst in inet sock.

rt->rt_iif is going to be encoded differently, so that we can
legitimately cache input routes in the FIB info more aggressively.

When the input interface is "use SKB device index" the rt->rt_iif will
be set to zero.

This forces us to move the TCP RX dst cache installation into the ipv4
specific code, and as well it should since doing the route caching for
ipv6 is pointless at the moment since it is not inspected in the ipv6
input paths yet.

Also, remove the unlikely on dst->obsolete, all ipv4 dsts have
obsolete set to a non-zero value to force invocation of the check
callback.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-23 16:36:26 -07:00
Linus Torvalds
a66d2c8f7e Merge branch 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull the big VFS changes from Al Viro:
 "This one is *big* and changes quite a few things around VFS.  What's in there:

   - the first of two really major architecture changes - death to open
     intents.

     The former is finally there; it was very long in making, but with
     Miklos getting through really hard and messy final push in
     fs/namei.c, we finally have it.  Unlike his variant, this one
     doesn't introduce struct opendata; what we have instead is
     ->atomic_open() taking preallocated struct file * and passing
     everything via its fields.

     Instead of returning struct file *, it returns -E...  on error, 0
     on success and 1 in "deal with it yourself" case (e.g.  symlink
     found on server, etc.).

     See comments before fs/namei.c:atomic_open().  That made a lot of
     goodies finally possible and quite a few are in that pile:
     ->lookup(), ->d_revalidate() and ->create() do not get struct
     nameidata * anymore; ->lookup() and ->d_revalidate() get lookup
     flags instead, ->create() gets "do we want it exclusive" flag.

     With the introduction of new helper (kern_path_locked()) we are rid
     of all struct nameidata instances outside of fs/namei.c; it's still
     visible in namei.h, but not for long.  Come the next cycle,
     declaration will move either to fs/internal.h or to fs/namei.c
     itself.  [me, miklos, hch]

   - The second major change: behaviour of final fput().  Now we have
     __fput() done without any locks held by caller *and* not from deep
     in call stack.

     That obviously lifts a lot of constraints on the locking in there.
     Moreover, it's legal now to call fput() from atomic contexts (which
     has immediately simplified life for aio.c).  We also don't need
     anti-recursion logics in __scm_destroy() anymore.

     There is a price, though - the damn thing has become partially
     asynchronous.  For fput() from normal process we are guaranteed
     that pending __fput() will be done before the caller returns to
     userland, exits or gets stopped for ptrace.

     For kernel threads and atomic contexts it's done via
     schedule_work(), so theoretically we might need a way to make sure
     it's finished; so far only one such place had been found, but there
     might be more.

     There's flush_delayed_fput() (do all pending __fput()) and there's
     __fput_sync() (fput() analog doing __fput() immediately).  I hope
     we won't need them often; see warnings in fs/file_table.c for
     details.  [me, based on task_work series from Oleg merged last
     cycle]

   - sync series from Jan

   - large part of "death to sync_supers()" work from Artem; the only
     bits missing here are exofs and ext4 ones.  As far as I understand,
     those are going via the exofs and ext4 trees resp.; once they are
     in, we can put ->write_super() to the rest, along with the thread
     calling it.

   - preparatory bits from unionmount series (from dhowells).

   - assorted cleanups and fixes all over the place, as usual.

  This is not the last pile for this cycle; there's at least jlayton's
  ESTALE work and fsfreeze series (the latter - in dire need of fixes,
  so I'm not sure it'll make the cut this cycle).  I'll probably throw
  symlink/hardlink restrictions stuff from Kees into the next pile, too.
  Plus there's a lot of misc patches I hadn't thrown into that one -
  it's large enough as it is..."

* 'for-linus-2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (127 commits)
  ext4: switch EXT4_IOC_RESIZE_FS to mnt_want_write_file()
  btrfs: switch btrfs_ioctl_balance() to mnt_want_write_file()
  switch dentry_open() to struct path, make it grab references itself
  spufs: shift dget/mntget towards dentry_open()
  zoran: don't bother with struct file * in zoran_map
  ecryptfs: don't reinvent the wheels, please - use struct completion
  don't expose I_NEW inodes via dentry->d_inode
  tidy up namei.c a bit
  unobfuscate follow_up() a bit
  ext3: pass custom EOF to generic_file_llseek_size()
  ext4: use core vfs llseek code for dir seeks
  vfs: allow custom EOF in generic_file_llseek code
  vfs: Avoid unnecessary WB_SYNC_NONE writeback during sys_sync and reorder sync passes
  vfs: Remove unnecessary flushing of block devices
  vfs: Make sys_sync writeout also block device inodes
  vfs: Create function for iterating over block devices
  vfs: Reorder operations during sys_sync
  quota: Move quota syncing to ->sync_fs method
  quota: Split dquot_quota_sync() to writeback and cache flushing part
  vfs: Move noop_backing_dev_info check from sync into writeback
  ...
2012-07-23 12:27:27 -07:00
Eric Dumazet
563d34d057 tcp: dont drop MTU reduction indications
ICMP messages generated in output path if frame length is bigger than
mtu are actually lost because socket is owned by user (doing the xmit)

One example is the ipgre_tunnel_xmit() calling
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(mtu));

We had a similar case fixed in commit a34a101e1e (ipv6: disable GSO on
sockets hitting dst_allfrag).

Problem of such fix is that it relied on retransmit timers, so short tcp
sessions paid a too big latency increase price.

This patch uses the tcp_release_cb() infrastructure so that MTU
reduction messages (ICMP messages) are not lost, and no extra delay
is added in TCP transmits.

Reported-by: Maciej Żenczykowski <maze@google.com>
Diagnosed-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Nandita Dukkipati <nanditad@google.com>
Cc: Tom Herbert <therbert@google.com>
Cc: Tore Anderson <tore@fud.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-23 00:58:46 -07:00
David S. Miller
5e9965c15b Merge branch 'kill_rtcache'
The ipv4 routing cache is non-deterministic, performance wise, and is
subject to reasonably easy to launch denial of service attacks.

The routing cache works great for well behaved traffic, and the world
was a much friendlier place when the tradeoffs that led to the routing
cache's design were considered.

What it boils down to is that the performance of the routing cache is
a product of the traffic patterns seen by a system rather than being a
product of the contents of the routing tables.  The former of which is
controllable by external entitites.

Even for "well behaved" legitimate traffic, high volume sites can see
hit rates in the routing cache of only ~%10.

The general flow of this patch series is that first the routing cache
is removed.  We build a completely new rtable entry every lookup
request.

Next we make some simplifications due to the fact that removing the
routing cache causes several members of struct rtable to become no
longer necessary.

Then we need to make some amends such that we can legally cache
pre-constructed routes in the FIB nexthops.  Firstly, we need to
invalidate routes which are hit with nexthop exceptions.  Secondly we
have to change the semantics of rt->rt_gateway such that zero means
that the destination is on-link and non-zero otherwise.

Now that the preparations are ready, we start caching precomputed
routes in the FIB nexthops.  Output and input routes need different
kinds of care when determining if we can legally do such caching or
not.  The details are in the commit log messages for those changes.

The patch series then winds down with some more struct rtable
simplifications and other tidy ups that remove unnecessary overhead.

On a SPARC-T3 output route lookups are ~876 cycles.  Input route
lookups are ~1169 cycles with rpfilter disabled, and about ~1468
cycles with rpfilter enabled.

These measurements were taken with the kbench_mod test module in the
net_test_tools GIT tree:

git://git.kernel.org/pub/scm/linux/kernel/git/davem/net_test_tools.git

That GIT tree also includes a udpflood tester tool and stresses
route lookups on packet output.

For example, on the same SPARC-T3 system we can run:

	time ./udpflood -l 10000000 10.2.2.11

with routing cache:
real    1m21.955s       user    0m6.530s        sys     1m15.390s

without routing cache:
real    1m31.678s       user    0m6.520s        sys     1m25.140s

Performance undoubtedly can easily be improved further.

For example fib_table_lookup() performs a lot of excessive
computations with all the masking and shifting, some of it
conditionalized to deal with edge cases.

Also, Eric's no-ref optimization for input route lookups can be
re-instated for the FIB nexthop caching code path.  I would be really
pleased if someone would work on that.

In fact anyone suitable motivated can just fire up perf on the loading
of the test net_test_tools benchmark kernel module.  I spend much of
my time going:

bash# perf record insmod ./kbench_mod.ko dst=172.30.42.22 src=74.128.0.1 iif=2
bash# perf report

Thanks to helpful feedback from Joe Perches, Eric Dumazet, Ben
Hutchings, and others.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 17:04:15 -07:00
Al Viro
6120d3dbb1 get rid of ->scm_work_list
recursion in __scm_destroy() will be cut by delaying final fput()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-22 23:58:00 +04:00
John Fastabend
406a3c638c net: netprio_cgroup: rework update socket logic
Instead of updating the sk_cgrp_prioidx struct field on every send
this only updates the field when a task is moved via cgroup
infrastructure.

This allows sockets that may be used by a kernel worker thread
to be managed. For example in the iscsi case today a user can
put iscsid in a netprio cgroup and control traffic will be sent
with the correct sk_cgrp_prioidx value set but as soon as data
is sent the kernel worker thread isssues a send and sk_cgrp_prioidx
is updated with the kernel worker threads value which is the
default case.

It seems more correct to only update the field when the user
explicitly sets it via control group infrastructure. This allows
the users to manage sockets that may be used with other threads.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 12:44:01 -07:00
Neil Horman
5aa93bcf66 sctp: Implement quick failover draft from tsvwg
I've seen several attempts recently made to do quick failover of sctp transports
by reducing various retransmit timers and counters.  While its possible to
implement a faster failover on multihomed sctp associations, its not
particularly robust, in that it can lead to unneeded retransmits, as well as
false connection failures due to intermittent latency on a network.

Instead, lets implement the new ietf quick failover draft found here:
http://tools.ietf.org/html/draft-nishida-tsvwg-sctp-failover-05

This will let the sctp stack identify transports that have had a small number of
errors, and avoid using them quickly until their reliability can be
re-established.  I've tested this out on two virt guests connected via multiple
isolated virt networks and believe its in compliance with the above draft and
works well.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-sctp@vger.kernel.org
CC: joe@perches.com
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-22 12:13:46 -07:00
David S. Miller
0bb4087cbe ipv4: Fix neigh lookup keying over loopback/point-to-point devices.
We were using a special key "0" for all loopback and point-to-point
device neigh lookups under ipv4, but we wouldn't use that special
key for the neigh creation.

So basically we'd make a new neigh at each and every lookup :-)

This special case to use only one neigh for these device types
is of dubious value, so just remove it entirely.

Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 16:06:10 -07:00
David S. Miller
2860583fe8 ipv4: Kill rt->fi
It's not really needed.

We only grabbed a reference to the fib_info for the sake of fib_info
local metrics.

However, fib_info objects are freed using RCU, as are therefore their
private metrics (if any).

We would have triggered a route cache flush if we eliminated a
reference to a fib_info object in the routing tables.

Therefore, any existing cached routes will first check and see that
they have been invalidated before an errant reference to these
metric values would occur.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:40:07 -07:00
David S. Miller
9917e1e876 ipv4: Turn rt->rt_route_iif into rt->rt_is_input.
That is this value's only use, as a boolean to indicate whether
a route is an input route or not.

So implement it that way, using a u16 gap present in the struct
already.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:40:02 -07:00
David S. Miller
4fd551d7be ipv4: Kill rt->rt_oif
Never actually used.

It was being set on output routes to the original OIF specified in the
flow key used for the lookup.

Adjust the only user, ipmr_rt_fib_lookup(), for greater correctness of
the flowi4_oif and flowi4_iif values, thanks to feedback from Julian
Anastasov.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:38:34 -07:00
David S. Miller
ba3f7f04ef ipv4: Kill FLOWI_FLAG_RT_NOCACHE and associated code.
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:36:54 -07:00
David S. Miller
d2d68ba9fe ipv4: Cache input routes in fib_info nexthops.
Caching input routes is slightly simpler than output routes, since we
don't need to be concerned with nexthop exceptions.  (locally
destined, and routed packets, never trigger PMTU events or redirects
that will be processed by us).

However, we have to elide caching for the DIRECTSRC and non-zero itag
cases.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:36:40 -07:00
David S. Miller
f2bb4bedf3 ipv4: Cache output routes in fib_info nexthops.
If we have an output route that lacks nexthop exceptions, we can cache
it in the FIB info nexthop.

Such routes will have DST_HOST cleared because such routes refer to a
family of destinations, rather than just one.

The sequence of the handling of exceptions during route lookup is
adjusted to make the logic work properly.

Before we allocate the route, we lookup the exception.

Then we know if we will cache this route or not, and therefore whether
DST_HOST should be set on the allocated route.

Then we use DST_HOST to key off whether we should store the resulting
route, during rt_set_nexthop(), in the FIB nexthop cache.

With help from Eric Dumazet.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:36:16 -07:00
David S. Miller
ceb3320610 ipv4: Kill routes during PMTU/redirect updates.
Mark them obsolete so there will be a re-lookup to fetch the
FIB nexthop exception info.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:22 -07:00
David S. Miller
f5b0a87436 net: Document dst->obsolete better.
Add a big comment explaining how the field works, and use defines
instead of magic constants for the values assigned to it.

Suggested by Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:21 -07:00
David S. Miller
f8126f1d51 ipv4: Adjust semantics of rt->rt_gateway.
In order to allow prefixed routes, we have to adjust how rt_gateway
is set and interpreted.

The new interpretation is:

1) rt_gateway == 0, destination is on-link, nexthop is iph->daddr

2) rt_gateway != 0, destination requires a nexthop gateway

Abstract the fetching of the proper nexthop value using a new
inline helper, rt_nexthop(), as suggested by Joe Perches.

Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Vijay Subramanian <subramanian.vijay@gmail.com>
2012-07-20 13:31:20 -07:00
David S. Miller
f1ce3062c5 ipv4: Remove 'rt_dst' from 'struct rtable'
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:19 -07:00
David Miller
b48698895d ipv4: Remove 'rt_mark' from 'struct rtable'
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:18 -07:00
David Miller
d6c0a4f609 ipv4: Kill 'rt_src' from 'struct rtable'
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:31:00 -07:00
David Miller
1a00fee4ff ipv4: Remove rt_key_{src,dst,tos} from struct rtable.
They are always used in contexts where they can be reconstituted,
or where the finally resolved rt->rt_{src,dst} is semantically
equivalent.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-07-20 13:30:59 -07:00