Commit Graph

16590 Commits

Author SHA1 Message Date
Dan Carpenter aef3ea33e8 rds: spin_lock_irq() is not nestable
This is basically just a cleanup.  IRQs were disabled on the previous
line so we don't need to do it again here.  In the current code IRQs
would get turned on one line earlier than intended.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-19 11:59:44 -07:00
Dan Carpenter f4fa7f3807 rds: double unlock in rds_ib_cm_handle_connect()
We unlock after we goto out.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-19 11:59:44 -07:00
Dan Carpenter 9b9d2e00bf rds: signedness bug
In the original code if the copy_from_user() fails in rds_rdma_pages()
then the error handling fails and we get a stack trace from kmalloc().

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-19 11:59:43 -07:00
Ben Hutchings be2902daee ethtool, ixgbe: Move RX n-tuple mask fixup to ethtool
The ethtool utility does not set masks for flow parameters that are
not specified, so if both value and mask are 0 then this must be
treated as equivalent to a mask with all bits set.  Currently that is
done in the only driver that implements RX n-tuple filtering, ixgbe.
Move it to the ethtool core.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-17 16:53:23 -07:00
Vlad Yasevich 4bdab43323 sctp: Do not reset the packet during sctp_packet_config().
sctp_packet_config() is called when getting the packet ready
for appending of chunks.  The function should not touch the
current state, since it's possible to ping-pong between two
transports when sending, and that can result packet corruption
followed by skb overlfow crash.

Reported-by: Thomas Dreibholz <dreibh@iem.uni-due.de>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-17 16:47:56 -07:00
David Lamparter 3b27e10555 netns: keep vlan slaves on master netns move
previously, if a vlan master device was moved from one network namespace
to another, all 802.1q and macvlan slaves were deleted.

we can use dev->reg_state to figure out whether dev_change_net_namespace
is happening, since that won't set dev->reg_state NETREG_UNREGISTERING.
so, this changes 8021q and macvlan to ignore NETDEV_UNREGISTER when
reg_state is not NETREG_UNREGISTERING.

Signed-off-by: David Lamparter <equinox@diac24.net>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Daniel Lezcano <daniel.lezcano@free.fr>
Acked-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-17 16:46:04 -07:00
Eric Dumazet 67c9660831 ethtool: change ethtool_set_gro() to use ethtool_op_get_rx_csum
To be able to switch on GRO on a device, ethtool_set_gro() checks this
device provides a get_rx_csum() method.

Some devices dont provide this method, while they do support RX
checksumming.

This patch allows bonding to support GRO :

ethtool -K bond0 gro on

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-17 11:56:18 -07:00
Dan Carpenter 2507136f74 net/llc: storing negative error codes in unsigned short
If the alloc_skb() fails then we return 65431 instead of -ENOBUFS
(-105).

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-16 22:38:23 -07:00
Eric Dumazet 9476763262 ip6tnl: get rid of ip6_tnl_lock
As RTNL is held while doing tunnels inserts and deletes, we can remove
ip6_tnl_lock spinlock. My initial RCU conversion was conservative and
converted the rwlock to spinlock, with no RTNL requirement.

Use appropriate rcu annotations and modern lockdep checks as well.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-16 21:58:44 -07:00
Eric Dumazet e71895a1be xfrm: dont assume rcu_read_lock in xfrm_output_one()
ip_local_out() is called with rcu_read_lock() held from ip_queue_xmit()
but not from other call sites.

Reported-and-bisected-by: Nick Bowler <nbowler@elliptictech.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-16 21:46:15 -07:00
Stephen Rothwell caeda9b926 net: include inetdevice.h for rcu_dereference_raw api change
rcu_dereference_raw() now needs to know the type of its argument.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-16 21:39:16 -07:00
Luis R. Rodriguez f01a067d9e mac80211: send last 3/5 probe requests as unicast
Some buggy APs do not respond to unicast probe requests
or send unicast probe requests very delayed so in the
worst case we should try to send broadcast probe requests,
otherwise we can get disconnected from these APs.

Even if drivers do not have filters to disregard probe
responses from foreign APs mac80211 will only process
probe responses from our associated AP for re-arming
connection monitoring.

We need to do this since the beacon monitor does not
push back the connection monitor by design so even if we
are getting beacons from these type of APs our connection
monitor currently relies heavily on the way the probe
requests are received on the AP. An example of an AP
affected by this is the Nexus One, but this has also been
observed with random APs.

We can probably optimize this later by using null funcs
instead of probe requests.

For more details refer to:

http://code.google.com/p/chromium-os/issues/detail?id=5715

This patch has fixes for stable kernels [2.6.35+].

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:18 -04:00
Luis R. Rodriguez 3bc3c0d748 mac80211: disable beacon monitor while going offchannel
The beacon monitor should be disabled when going off channel
to prevent spurious warnings and triggering connection
deterioration work such as sending probe requests. Re-enable
the beacon monitor once we come back to the home channel.

This patch has fixes for stable kernels [2.6.34+].

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:17 -04:00
Luis R. Rodriguez d3a910a8e4 mac80211: make the beacon monitor available externally
This will be used by other components next. The beacon
monitor was added as of 2.6.34 so these fixes are applicable
only to kernels >= 2.6.34.

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:16 -04:00
Luis R. Rodriguez 4730d5977f mac80211: reset connection idle when going offchannel
When we go offchannel mac80211 currently leaves alive the
connection idle monitor. This should be instead postponed
until we come back to our home channel, otherwise by the
time we get back to the home channel we could be triggering
unecesary probe requests. For APs that do not respond to
unicast probe requests (Nexus One is a simple example) this
means we essentially get disconnected after the probes
fails.

This patch has stable fixes for kernels [2.6.35+]

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:15 -04:00
Luis R. Rodriguez 0c699c3a75 mac80211: reset probe send counter upon connection timer reset
Upon beacon loss we send probe requests after 30 seconds of idle
time and we wait for each probe response 1/2 second. We send a
total of 3 probe requests before giving up on the AP. In the case
that we reset the connection idle monitor we should reset the probe
requests count to 0. Right now this won't help in any way but
the next patch will.

This patch has fixes for stable kernel [2.6.35+].

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:14 -04:00
Luis R. Rodriguez be099e82e9 mac80211: add helper for reseting the connection monitor
This will be used in another place later. The connection
monitor was added as of 2.6.35 so these fixes will be
applicable to >= 2.6.35.

Cc: stable@kernel.org
Cc: Paul Stewart <pstew@google.com>
Cc: Amod Bodas <amod.bodas@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:13 -04:00
Johannes Berg 2ca27bcff7 mac80211: add p2p device type support
When a driver advertises p2p device support,
mac80211 will handle it, but internally it will
rewrite the interface type to STA/AP rather than
P2P-STA/GO since otherwise a lot of paths need
to be touched that are otherwise identical. A
p2p boolean tells drivers whether or not a given
interface will be used for p2p or not.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:07 -04:00
Johannes Berg 074ac8df9f cfg80211/nl80211: introduce p2p device types
This adds P2P-STA and P2P-GO as device types so
we can distinguish between those and normal STA
or AP (respectively) type interfaces.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:06 -04:00
Johannes Berg 2d2080c3c1 mac80211: set running state earlier
When an interface is brought up, the recent changes
to allow changing type-while-up only set the running
bit after everything was done. This broke a number
of things, including idle calculation for monitor
interfaces, and it also broke WDS station insertion
(although nobody noticed yet).

Thus, change the code to set the running bit earlier,
but keep it after the driver's add_interface was
called because otherwise drivers may iterate over
interfaces they haven't fully set up yet.

Reported-by: Rajkumar Manoharan <rmanoharan@atheros.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:01 -04:00
Johannes Berg 46a5ebaf02 cfg80211/mac80211: use lockdep_assert_held
Instead of using a WARN_ON(!mutex_is_locked())
use lockdep_assert_held() which compiles away
completely when lockdep isn't enabled, and
also is a more accurate assertion since it
checks that the current thread is holding the
mutex.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:46:00 -04:00
Johannes Berg f5521b1388 mac80211: use correct station flags lock
This code is modifying the station flags, and
as such should hold the flags lock so it can
do so atomically vs. other flags modifications
and readers. This issue was introduced when
this code was added in eccb8e8f, as it used
the wrong lock (thus not fixing the race that
was previously documented in a comment.)

Cc: stable@kernel.org [2.6.31+]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:45:58 -04:00
Joe Perches 9c37663929 include/net/cfg80211.h: wiphy_<level> messages use dev_printk
The output becomes:

[   41.261941] ieee80211 phy0: Selected rate control algorithm 'minstrel_ht'

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-16 15:19:44 -04:00
Brandon Philips 16c3ea785f net: enable GRO by default for vlan devices
Currently vlan devices don't have GRO by default as none of the Ethernet
drivers add NETIF_F_GRO to their vlan_features.

As GRO is a software feature add GRO to dev->vlan_features in
register_netdevice() and let vlan_dev_init() take care that it gets
enabled only when dev->features has NETIF_F_GRO too.

Signed-off-by: Brandon Philips <bphilips@suse.de>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 22:32:29 -07:00
Eric Dumazet 95ae6b228f ipv4: ip_ptr cleanups
dev->ip_ptr is protected by rtnl and rcu.

Yet some places dont use appropriate primitives and/or locking rules.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 22:06:05 -07:00
David S. Miller 9e0064a545 phonet: Fix build warning.
net/phonet/socket.c: In function ‘pn_res_seq_show’:
net/phonet/socket.c:726: warning: format ‘%02X’ expects type ‘unsigned int’, but argument 3 has type ‘long int’

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:34:41 -07:00
Rémi Denis-Courmont 507215f8d0 Phonet: list subscribed resources via proc_fs
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:31:33 -07:00
Rémi Denis-Courmont b6a563b2af Phonet: look up the resource routing table when forwarding
Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:31:33 -07:00
Rémi Denis-Courmont 7417fa83c1 Phonet: hook resource routing to userspace via ioctl()'s
I wish we could use something cleaner, such as bind(). But that would
not work since resource subscription is orthogonal/in addition to the
normal object ID allocated via bind(). This is similar to multicasting
which also uses ioctl()'s.

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:31:32 -07:00
Rémi Denis-Courmont 4e3d16ce5e Phonet: resource routing backend
When both destination device and object are nul, Phonet routes the
packet according to the resource field. In fact, this is the most
common pattern when sending Phonet "request" packets. In this case,
the packet is delivered to whichever endpoint (socket) has
registered the resource.

This adds a new table so that Linux processes can register their
Phonet sockets to Phonet resources, if they have adequate privileges.

(Namespace support is not implemented at the moment.)

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:31:32 -07:00
Rémi Denis-Courmont 6482f554e2 Phonet: remove dangling pipe if an endpoint is closed early
Closing a pipe endpoint is not normally allowed by the Phonet pipe,
other than as a side after-effect of removing the pipe between two
endpoints. But there is no way to prevent Linux userspace processes
from being killed or suffering from bugs, so this can still happen.
We might as well forcefully close Phonet pipe endpoints then.

The cellular modem supports only a few existing pipes at a time. So we
really should not leak them. This change instructs the modem to destroy
the pipe if either of the pipe's endpoint (Linux socket) is closed too
early.

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 21:31:31 -07:00
David S. Miller 7fedd7e5df Merge branch 'dccp' of git://eden-feed.erg.abdn.ac.uk/net-next-2.6 2010-09-15 20:21:48 -07:00
Arnd Bergmann 0a5f1d476a irda/irnet: use noop_llseek
There may be applications trying to seek
on the irnet character device, so we should
use noop_llseek to avoid returning an error
when the default llseek changes to no_llseek.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: netdev@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 19:29:55 -07:00
Eric Dumazet 3a43be3c32 sit: get rid of ipip6_lock
As RTNL is held while doing tunnels inserts and deletes, we can remove
ipip6_lock spinlock. My initial RCU conversion was conservative and
converted the rwlock to spinlock, with no RTNL requirement.

Use appropriate rcu annotations and modern lockdep checks as well.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 19:29:47 -07:00
Eric Dumazet 1507850b40 gre: get rid of ipgre_lock
As RTNL is held while doing tunnels inserts and deletes, we can remove
ipgre_lock spinlock. My initial RCU conversion was conservative and
converted the rwlock to spinlock, with no RTNL requirement.

Use appropriate rcu annotations and modern lockdep checks as well.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 19:29:46 -07:00
Eric Dumazet b7285b7912 ipip: get rid of ipip_lock
As RTNL is held while doing tunnels inserts and deletes, we can remove
ipip_lock spinlock. My initial RCU conversion was conservative and
converted the rwlock to spinlock, with no RTNL requirement.

Use appropriate rcu annotations and modern lockdep checks as well.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 19:29:46 -07:00
Ben Hutchings e0de7c93b9 ethtool: Remove unimplemented flow specification types
struct ethtool_rawip4_spec and struct ethtool_ether_spec are neither
commented nor used by any driver, so remove them.  Adjust padding in
the user-visible unions that included these structures.

Fix references to struct ethtool_rawip4_spec in
ethtool_get_rx_ntuple(), which should use struct ethtool_usrip4_spec.

struct ethtool_usrip4_spec cannot hold IPv6 host addresses and there
is no separate structure that can, so remove ETH_RX_NFC_IP6 and the
reference to it in niu.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-15 14:42:13 -07:00
Gerrit Renker 37efb03fbd dccp ccid-3: Simplify and consolidate tx_parse_options
This simplifies and consolidates the TX option-parsing code:

 1. The Loss Intervals option is not currently used, so dead code related to
    this option is removed. I am aware of no plans to support the option, but
    if someone wants to implement it (e.g. for inter-op tests), it is better
    to start afresh than having to also update currently unused code.

 2. The Loss Event and Receive Rate options have a lot of code in common (both
    are 32 bit, both have same length etc.), so this is consolidated.

 3. The test against GSR is not necessary, because
    - on first loading CCID3, ccid_new() zeroes out all fields in the socket;
    - ccid3_hc_tx_packet_recv() treats 0 and ~0U equivalently, due to

	pinv = opt_recv->ccid3or_loss_event_rate;
	if (pinv == ~0U || pinv == 0)
		hctx->p = 0;

    - as a result, the sequence number field is removed from opt_recv.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2010-09-15 12:36:02 +02:00
Gerrit Renker d2c726309d dccp ccid-3: remove buggy RTT-sampling history lookup
This removes the RTT-sampling function tfrc_tx_hist_rtt(), since

 1. it suffered from complex passing of return values (the return value both
    indicated successful lookup while the value doubled as RTT sample);

 2. when for some odd reason the sample value equalled 0, this triggered a bug
    warning about "bogus Ack", due to the ambiguity of the return value;

 3. on a passive host which has not sent anything the TX history is empty and
    thus will lead to unwanted "bogus Ack" warnings such as
    ccid3_hc_tx_packet_recv: server(e7b7d518): DATAACK with bogus ACK-28197148
    ccid3_hc_tx_packet_recv: server(e7b7d518): DATAACK with bogus ACK-26641606.

The fix is to replace the implicit encoding by performing the steps manually.

Furthermore, the "bogus Ack" warning has been removed, since it can actually be
triggered due to several reasons (network reordering, old packet, (3) above),
hence it is not very useful.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2010-09-15 12:36:02 +02:00
Gerrit Renker 20cbd3e120 dccp ccid-3: A lower bound for the inter-packet scheduling algorithm
This fixes a subtle bug in the calculation of the inter-packet gap and shows
that t_delta, as it is currently used, is not needed.

The algorithm from RFC 5348, 8.3 below continually computes a send time t_nom,
which is initialised with the current time t_now; t_gran = 1E6 / HZ specifies
the scheduling granularity, s the packet size, and X the sending rate:

  t_distance = t_nom - t_now;		// in microseconds
  t_delta    = min(t_ipi, t_gran) / 2;	// `delta' parameter in microseconds

  if (t_distance >= t_delta) {
	reschedule after (t_distance / 1000) milliseconds;
  } else {
  	t_ipi  = s / X;			// inter-packet interval in usec
	t_nom += t_ipi;			// compute the next send time
	send packet now;
  }

Problem:
--------
Rescheduling requires a conversion into milliseconds (sk_reset_timer()). The
highest jiffy resolution with HZ=1000 is 1 millisecond, so using a higher
granularity does not make much sense here.

As a consequence, values of t_distance < 1000 are truncated to 0. This issue
has so far been resolved by using instead

  if (t_distance >= t_delta + 1000)
	reschedule after (t_distance / 1000) milliseconds;

This is unnecessarily large, a lower bound is t_delta' = max(t_delta, 1000).
And it implies a further simplification:

 a) when HZ >= 500, then t_delta <= t_gran/2 = 10^6/(2*HZ) <= 1000, so that
    t_delta' = MAX(1000, t_delta) = 1000 (constant value);

 b) when HZ < 500, then t_delta = 1/2*MIN(rtt, t_ipi, t_gran) <= t_gran/2,
    so that 1000 <= t_delta' <= t_gran/2.

The maximum error of using a constant t_delta in (b) is less than half a jiffy.

Fix:
----
The patch replaces t_delta with a constant, whose value depends on CONFIG_HZ,
changing the above algorithm to:

  if (t_distance >= t_delta')
	reschedule after (t_distance / 1000) milliseconds;

where t_delta' = 10^6/(2*HZ) if HZ < 500, and t_delta' = 1000 otherwise.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
2010-09-15 12:36:01 +02:00
David S. Miller 6dcbc12290 net: RPS needs to depend upon USE_GENERIC_SMP_HELPERS
You cannot invoke __smp_call_function_single() unless the
architecture sets this symbol.

Reported-by: Daniel Hellstrom <daniel@gaisler.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 21:42:22 -07:00
andrew hendry 21a4591794 X.25 remove bkl in connect
Connect already has socket locking.

Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:39:09 -07:00
Andrew Hendry 141646ce56 X.25 remove bkl in accept
Accept already has socket locking.

[ Extend socket locking over TCP_LISTEN state test. -DaveM ]

Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:38:54 -07:00
andrew hendry 90c27297a9 X.25 remove bkl in bind
Accept updates socket values in 3 lines so wrapped with lock_sock.

Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:34:52 -07:00
andrew hendry 25aa4efe4f X.25 remove bkl in listen
Listen updates socket values and needs lock_sock.

Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:34:52 -07:00
Joe Perches 55b1804c67 net/irda: Use static const char * const where possible
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 20:22:05 -07:00
Eric Dumazet ef885afbf8 net: use rcu_barrier() in rollback_registered_many
netdev_wait_allrefs() waits that all references to a device vanishes.

It currently uses a _very_ pessimistic 250 ms delay between each probe.
Some users reported that no more than 4 devices can be dismantled per
second, this is a pretty serious problem for some setups.

Most of the time, a refcount is about to be released by an RCU callback,
that is still in flight because rollback_registered_many() uses a
synchronize_rcu() call instead of rcu_barrier(). Problem is visible if
number of online cpus is one, because synchronize_rcu() is then a no op.

time to remove 50 ipip tunnels on a UP machine :

before patch : real 11.910s
after patch : real 1.250s

Reported-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reported-by: Octavian Purdila <opurdila@ixiacom.com>
Reported-by: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-14 14:27:29 -07:00
Johannes Berg a2c1e3dad5 mac80211: match only assigned bss in sta_info_get_bss
sta_info_get_bss() is used to match STA pointers
for VLAN/AP interfaces, but if the same station
is also added to multiple other interfaces it
will erroneously match because both pointers are
NULL, fix this by ignoring NULL pointers here.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:14:27 -04:00
Stanislaw Gruszka edeb78a7fa mac80211: wait for scan work complete before restarting hw
This is needed to avoid warning in ieee80211_restart_hw about hardware
scan in progress.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Acked-by: Wey-Yi W Guy <wey-yi.w.guy@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:14:25 -04:00
Steve deRosier 740c1aa3b0 mac80211: Fix dangling pointer in ieee80211_xmit
hdr pointer is left dangling after call to ieee80211_skb_resize. This
can cause guards around mesh path selection to fail.

Signed-off-by: Steve deRosier <steve@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:08:03 -04:00
Bill Jordan a1e567c83f nl80211: Uninitialized variable
There is a path in nl80211_set_wiphy where result is tested but
uninitialized.

I am hitting this path when I attempt:

sh# iw dev wlan0 set channel 10
command failed: Unknown error 1069727332 (-1069727332)

Signed-off-by: William Jordan <bjordan@rajant.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:08:03 -04:00
Nikitas Angelinas 942623166d net/wireless: use ARRAY_SIZE macro in radiotap.c
Replace sizeof(rtap_namespace_sizes) / sizeof(rtap_namespace_sizes[0])
with ARRAY_SIZE(rtap_namespace_sizes) in net/wireless/radiotap.c

Signed-off-by: Nikitas Angelinas <nikitasangelinas@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-09-14 16:05:57 -04:00
Eric Dumazet 83b6b1f5d1 flow: better memory management
Allocate hash tables for every online cpus, not every possible ones.

NUMA aware allocations.

Dont use a full page on arches where PAGE_SIZE > 1024*sizeof(void *)

misc:
  __percpu , __read_mostly, __cpuinit annotations
  flow_compare_t is just an "unsigned long"

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 20:02:50 -07:00
Michael Kerrisk a89b47639f ipv4: enable getsockopt() for IP_NODEFRAG
While integrating your man-pages patch for IP_NODEFRAG, I noticed
that this option is settable by setsockopt(), but not gettable by
getsockopt(). I suppose this is not intended. The (untested,
trivial) patch below adds getsockopt() support.

Signed-off-by: Michael kerrisk <mtk.manpages@gmail.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 19:57:23 -07:00
Bob Arendt 7998156344 ipv4: force_igmp_version ignored when a IGMPv3 query received
After all these years, it turns out that the
    /proc/sys/net/ipv4/conf/*/force_igmp_version
parameter isn't fully implemented.

*Symptom*:
When set force_igmp_version to a value of 2, the kernel should only perform
multicast IGMPv2 operations (IETF rfc2236).  An host-initiated Join message
will be sent as a IGMPv2 Join message.  But if a IGMPv3 query message is
received, the host responds with a IGMPv3 join message.  Per rfc3376 and
rfc2236, a IGMPv2 host should treat a IGMPv3 query as a IGMPv2 query and
respond with an IGMPv2 Join message.

*Consequences*:
This is an issue when a IGMPv3 capable switch is the querier and will only
issue IGMPv3 queries (which double as IGMPv2 querys) and there's an
intermediate switch that is only IGMPv2 capable.  The intermediate switch
processes the initial v2 Join, but fails to recognize the IGMPv3 Join responses
to the Query, resulting in a dropped connection when the intermediate v2-only
switch times it out.

*Identifying issue in the kernel source*:
The issue is in this section of code (in net/ipv4/igmp.c), which is called when
an IGMP query is received  (from mainline 2.6.36-rc3 gitweb):
 ...
A IGMPv3 query has a length >= 12 and no sources.  This routine will exit after
line 880, setting the general query timer (random timeout between 0 and query
response time).  This calls igmp_gq_timer_expire():
...
.. which only sends a v3 response.  So if a v3 query is received, the kernel
always sends a v3 response.

IGMP queries happen once every 60 sec (per vlan), so the traffic is low.  A
IGMPv3 query *is* a strict superset of a IGMPv2 query, so this patch properly
short circuit's the v3 behaviour.

One issue is that this does not address force_igmp_version=1.  Then again, I've
never seen any IGMPv1 multicast equipment in the wild.  However there is a lot
of v2-only equipment. If it's necessary to support the IGMPv1 case as well:

837         if (len == 8 || IGMP_V2_SEEN(in_dev) || IGMP_V1_SEEN(in_dev)) {

Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 12:56:51 -07:00
Dan Carpenter 339db11b21 net/llc: make opt unsigned in llc_ui_setsockopt()
The members of struct llc_sock are unsigned so if we pass a negative
value for "opt" it can cause a sign bug.  Also it can cause an integer
overflow when we multiply "opt * HZ".

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-13 12:44:10 -07:00
David S. Miller a505b3b30f sch_atm: Fix potential NULL deref.
The list_head conversion unearther an unnecessary flow
check.  Since flow is always NULL here we don't need to
see if a matching flow exists already.

Reported-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-12 11:56:44 -07:00
stephen hemminger 9ca7f87622 pkt_sched: remov unnecessary bh_disable
Now that est_tree_lock is acquired with BH protection, the other
call is unnecessary.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-10 12:47:59 -07:00
Eric Dumazet a034ee3cca fib: cleanups
Use rcu_dereference_rtnl() helper

Change hard coded constants in fib_flag_trans()
 7 -> RTN_UNREACHABLE
 8 -> RTN_PROHIBIT

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-10 12:32:02 -07:00
David S. Miller e548833df8 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	net/mac80211/main.c
2010-09-09 22:27:33 -07:00
Paul Gortmaker b2abd4c033 tipc: Optimize handling excess content on incoming messages
Remove code that trimmed excess trailing info from incoming messages
arriving over an Ethernet interface.  TIPC now ignores the extra info
while the message is being processed by the node, and only trims it off
if the message is retransmitted to another node.  (This latter step is
done to ensure the extra info doesn't cause the sk_buff to exceed the
outgoing interface's MTU limit.) The outgoing buffer is guaranteed to
be linear.

Signed-off-by: Allan Stephens <allan.stephens@windriver.com>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 21:34:14 -07:00
Eric Dumazet 49d61e2390 tunnels: missing rcu_assign_pointer()
xfrm4_tunnel_register() & xfrm6_tunnel_register() should
use rcu_assign_pointer() to make sure previous writes
(to handler->next) are committed to memory before chain
insertion.

deregister functions dont need a particular barrier.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:39 -07:00
Namhyung Kim f39234d606 net/core: add lock context change annotations in net/core/sock.c
__lock_sock() and __release_sock() releases and regrabs lock but
were missing proper annotations. Add it. This removes following
warning from sparse. (Currently __lock_sock() does not emit any
warning about it but I think it is better to add also.)

 net/core/sock.c:1580:17: warning: context imbalance in '__release_sock' - unexpected unlock

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:39 -07:00
Namhyung Kim a700d8be73 net/core: remove address space warnings on verify_iovec()
move_addr_to_kernel() and copy_from_user() requires their argument
as __user pointer but were missing proper markups. Add it.
This removes following warnings from sparse.

 net/core/iovec.c:44:52: warning: incorrect type in argument 1 (different address spaces)
 net/core/iovec.c:44:52:    expected void [noderef] <asn:1>*uaddr
 net/core/iovec.c:44:52:    got void *msg_name
 net/core/iovec.c:55:34: warning: incorrect type in argument 2 (different address spaces)
 net/core/iovec.c:55:34:    expected void const [noderef] <asn:1>*from
 net/core/iovec.c:55:34:    got struct iovec *msg_iov

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:02:38 -07:00
Joe Perches 123031c0ee sctp: fix test for end of loop
Add a list_has_sctp_addr function to simplify loop

Based on a patches by Dan Carpenter and David Miller

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-09 15:00:29 -07:00
David S. Miller cf0ac2b8a7 Merge branch 'for-davem' of git://oss.oracle.com/git/agrover/linux-2.6 2010-09-09 14:58:11 -07:00
David S. Miller e199e6136c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/torvalds/linux-2.6 2010-09-08 23:49:04 -07:00
Eric Dumazet 719f835853 udp: add rehash on connect()
commit 30fff923 introduced in linux-2.6.33 (udp: bind() optimisation)
added a secondary hash on UDP, hashed on (local addr, local port).

Problem is that following sequence :

fd = socket(...)
connect(fd, &remote, ...)

not only selects remote end point (address and port), but also sets
local address, while UDP stack stored in secondary hash table the socket
while its local address was INADDR_ANY (or ipv6 equivalent)

Sequence is :
 - autobind() : choose a random local port, insert socket in hash tables
              [while local address is INADDR_ANY]
 - connect() : set remote address and port, change local address to IP
              given by a route lookup.

When an incoming UDP frame comes, if more than 10 sockets are found in
primary hash table, we switch to secondary table, and fail to find
socket because its local address changed.

One solution to this problem is to rehash datagram socket if needed.

We add a new rehash(struct socket *) method in "struct proto", and
implement this method for UDP v4 & v6, using a common helper.

This rehashing only takes care of secondary hash table, since primary
hash (based on local port only) is not changed.

Reported-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Krzysztof Piotr Oledzki <ole@ans.pl>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-08 21:45:01 -07:00
Eric Dumazet e0386005ff net: inet_add_protocol() can use cmpxchg()
Use cmpxchg() to get rid of spinlocks in inet_add_protocol() and
friends.

inet_protos[] & inet6_protos[] are moved to read_mostly section

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-09-08 21:31:35 -07:00
Andy Grover 20c72bd5f5 RDS: Implement masked atomic operations
Add two CMSGs for masked versions of cswp and fadd. args
struct modified to use a union for different atomic op type's
arguments. Change IB to do masked atomic ops. Atomic op type
in rds_message similarly unionized.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:51 -07:00
Zach Brown 59f740a6ae RDS/IB: print string constants in more places
This prints the constant identifier for work completion status and rdma
cm event types, like we already do for IB event types.

A core string array helper is added that each string type uses.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:50 -07:00
Zach Brown 4518071ac1 RDS: cancel connection work structs as we shut down
Nothing was canceling the send and receive work that might have been
queued as a conn was being destroyed.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:49 -07:00
Zach Brown ffcec0e110 RDS: don't call rds_conn_shutdown() from rds_conn_destroy()
rds_conn_shutdown() can return before the connection is shut down when
it encounters an existing state that it doesn't understand.  This lets
rds_conn_destroy() then start tearing down the conn from under paths
that are still using it.

It's more reliable the shutdown work and wait for krdsd to complete the
shutdown callback.  This stopped some hangs I was seeing where krdsd was
trying to shut down a freed conn.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:48 -07:00
Zach Brown 5adb5bc65f RDS: have sockets get transport module references
Right now there's nothing to stop the various paths that use
rs->rs_transport from racing with rmmod and executing freed transport
code.  The simple fix is to have binding to a transport also hold a
reference to the transport's module, removing this class of races.

We already had an unused t_owner field which was set for the modular
transports and which wasn't set for the built-in loop transport.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:47 -07:00
Zach Brown 77510481c0 RDS: remove old rs_transport comment
rs_transport is now also used by the rdma paths once the socket is
bound.  We don't need this stale comment to tell us what cscope can.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:46 -07:00
Zach Brown fe8ff6b58f RDS: lock rds_conn_count decrement in rds_conn_destroy()
rds_conn_destroy() can race with all other modifications of the
rds_conn_count but it was modifying the count without locking.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:45 -07:00
Zach Brown ea819867b7 RDS/IB: protect the list of IB devices
The RDS IB device list wasn't protected by any locking.  Traversal in
both the get_mr and FMR flushing paths could race with additon and
removal.

List manipulation is done with RCU primatives and is protected by the
write side of a rwsem.  The list traversal in the get_mr fast path is
protected by a rcu read critical section.  The FMR list traversal is
more problematic because it can block while traversing the list.  We
protect this with the read side of the rwsem.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:44 -07:00
Zach Brown 1bde04a63d RDS/IB: print IB event strings as well as their number
It's nice to not have to go digging in the code to see which event
occurred.  It's easy to throw together a quick array that maps the ib
event enums to their strings.  I didn't see anything in the stack that
does this translation for us, but I also didn't look very hard.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:43 -07:00
Chris Mason 8576f374ac RDS: flush fmrs before allocating new ones
Flushing FMRs is somewhat expensive, and is currently kicked off when
the interrupt handler notices that we are getting low.  The result of
this is that FMR flushing only happens from the interrupt cpus.

This spreads the load more effectively by triggering flushes just before
we allocate a new FMR.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:16:42 -07:00
Chris Mason b4e1da3c9a RDS: properly use sg_init_table
This is only needed to keep debugging code from bugging.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:16:41 -07:00
Zach Brown f046011cd7 RDS/IB: track signaled sends
We're seeing bugs today where IB connection shutdown clears the send
ring while the tasklet is processing completed sends.  Implementation
details cause this to dereference a null pointer.  Shutdown needs to
wait for send completion to stop before tearing down the connection.  We
can't simply wait for the ring to empty because it may contain
unsignaled sends that will never be processed.

This patch tracks the number of signaled sends that we've posted and
waits for them to complete.  It also makes sure that the tasklet has
finished executing.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:40 -07:00
Zach Brown ef87b7ea39 RDS: remove __init and __exit annotation
The trivial amount of memory saved isn't worth the cost of dealing with section
mismatches.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:39 -07:00
Andy Grover c20f5b9633 RDS/IB: Use SLAB_HWCACHE_ALIGN flag for kmem_cache_create()
We are *definitely* counting cycles as closely as DaveM, so
ensure hwcache alignment for our recv ring control structs.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:38 -07:00
Zach Brown d455ab6409 RDS/IB: always process recv completions
The recv refill path was leaking fragments because the recv event handler had
marked a ring element as free without freeing its frag.  This was happening
because it wasn't processing receives when the conn wasn't marked up or
connecting, as can be the case if it races with rmmod.

Two observations support always processing receives in the callback.

First, buildup should only post receives, thus triggering recv event handler
calls, once it has built up all the state to handle them.  Teardown should
destroy the CQ and drain the ring before tearing down the state needed to
process recvs.  Both appear to be true today.

Second, this test was fundamentally racy.  There is nothing to stop rmmod and
connection destruction from swooping in the moment after the conn state was
sampled but before real receive procesing starts.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:36 -07:00
Zach Brown 80c51be56f RDS: return to a single-threaded krdsd
We were seeing very nasty bugs due to fundamental assumption the current code
makes about concurrent work struct processing.  The code simpy isn't able to
handle concurrent connection shutdown work function execution today, for
example, which is very much possible once a multi-threaded krdsd was
introduced.  The problem compounds as additional work structs are added to the
mix.

krdsd is no longer perforance critical now that send and receive posting and
FMR flushing are done elsewhere, so the safest fix is to move back to the
single threaded krdsd that the current code was built around.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:35 -07:00
Zach Brown 515e079dab RDS/IB: create a work queue for FMR flushing
This patch moves the FMR flushing work in to its own mult-threaded work queue.
This is to maintain performance in preparation for returning the main krdsd
work queue back to a single threaded work queue to avoid deep-rooted
concurrency bugs.

This is also good because it further separates FMRs, which might be removed
some day, from the rest of the code base.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:34 -07:00
Zach Brown 8aeb1ba663 RDS/IB: destroy connections on rmmod
IB connections were not being destroyed during rmmod.

First, recently IB device removal callback was changed to disconnect
connections that used the removing device rather than destroying them.  So
connections with devices during rmmod were not being destroyed.

Second, rds_ib_destroy_nodev_conns() was being called before connections are
disassociated with devices.  It would almost never find connections in the
nodev list.

We first get rid of rds_ib_destroy_conns(), which is no longer called, and
refactor the existing caller into the main body of the function and get rid of
the list and lock wrappers.

Then we call rds_ib_destroy_nodev_conns() *after* ib_unregister_client() has
removed the IB device from all the conns and put the conns on the nodev list.

The result is that IB connections are destroyed by rmmod.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:33 -07:00
Zach Brown 24fa163a4b RDS/IB: wait for IB dev freeing work to finish during rmmod
The RDS IB client removal callback can queue work to drop the final reference
to an IB device.  We have to make sure that this function has returned before
we complete rmmod or the work threads can try to execute freed code.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:16:32 -07:00
Andy Grover b6fb0df12d RDS/IB: Make ib_recv_refill return void
Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:31 -07:00
Andy Grover fbf4d7e3d0 RDS: Remove unused XLIST_PTR_TAIL and xlist_protect()
Not used.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:16:06 -07:00
Andy Grover c9455d9996 RDS: whitespace 2010-09-08 18:15:32 -07:00
Chris Mason 7a0ff5dbdd RDS: use delayed work for the FMR flushes
Using a delayed work queue helps us make sure a healthy number of FMRs
have queued up over the limit.  It makes for a large improvement in RDMA
iops.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:15:30 -07:00
Chris Mason eabb732279 rds: more FMRs are faster
When we add more FMRs, we flush them less often and so we go faster.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:15:29 -07:00
Chris Mason 6fa70da608 rds: recycle FMRs through lockless lists
FRM allocation and recycling is performance critical and fairly lock
intensive.  The current code has a per connection lock that all
processes bang on and it becomes a major bottleneck on large systems.

This changes things to use a number of cmpxchg based lists instead,
allowing us to go through the whole FMR lifecycle without locking inside
RDS.

Zach Brown pointed out that our usage of cmpxchg for xlist removal is
racey if someone manages to remove and add back an FMR struct into the list
while another CPU can see the FMR's address at the head of the list.

The second CPU might assume the list hasn't changed when in fact any
number of operations might have happened in between the deletion and
reinsertion.

This commit maintains a per cpu count of CPUs that are currently
in xlist removal, and establishes a grace period to make sure that
nobody can see an entry we have just removed from the list.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:15:28 -07:00
Zach Brown 0f4b1c7e89 rds: fix rds_send_xmit() serialization
rds_send_xmit() was changed to hold an interrupt masking spinlock instead of a
mutex so that it could be called from the IB receive tasklet path.  This broke
the TCP transport because its xmit method can block and masks and unmasks
interrupts.

This patch serializes callers to rds_send_xmit() with a simple bit instead of
the current spinlock or previous mutex.  This enables rds_send_xmit() to be
called from any context and to call functions which block.  Getting rid of the
c_send_lock exposes the bare c_lock acquisitions which are changed to block
interrupts.

A waitqueue is added so that rds_conn_shutdown() can wait for callers to leave
rds_send_xmit() before tearing down partial send state.  This lets us get rid
of c_senders.

rds_send_xmit() is changed to check the conn state after acquiring the
RDS_IN_XMIT bit to resolve races with the shutdown path.  Previously both
worked with the conn state and then the lock in the same order, allowing them
to race and execute the paths concurrently.

rds_send_reset() isn't racing with rds_send_xmit() now that rds_conn_shutdown()
properly ensures that rds_send_xmit() can't start once the conn state has been
changed.  We can remove its previous use of the spinlock.

Finally, c_send_generation is redundant.  Callers can race to test the c_flags
bit by simply retrying instead of racing to test the c_send_generation atomic.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:15:27 -07:00
Zach Brown 501dcccdb7 rds: block ints when acquiring c_lock in rds_conn_message_info()
conn->c_lock is acquired in interrupt context.  rds_conn_message_info() is
called from user context and was acquiring c_lock without blocking interrupts,
leading to possible deadlocks.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:15:26 -07:00
Zach Brown 671202f349 rds: remove unused rds_send_acked_before()
rds_send_acked_before() wasn't blocking interrupts when acquiring c_lock from
user context but nothing calls it.  Rather than fix its use of c_lock we just
remove the function.

Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:15:25 -07:00
Chris Mason 037f18a307 RDS: use friendly gfp masks for prefill
When prefilling the rds frags, we end up doing a lot of allocations.
We're not in atomic context here, and so there's no reason to dip into
atomic reserves.  This changes the prefills to use masks that allow
waiting.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
2010-09-08 18:15:24 -07:00
Chris Mason 3324412587 RDS/IB: Add caching of frags and incs
This patch is based heavily on an initial patch by Chris Mason.
Instead of freeing slab memory and pages, it keeps them, and
funnels them back to be reused.

The lock minimization strategy uses xchg and cmpxchg atomic ops
for manipulation of pointers to list heads. We anchor the lists with a
pointer to a list_head struct instead of a static list_head struct.
We just have to carefully use the existing primitives with
the difference between a pointer and a static head struct.

For example, 'list_empty()' means that our anchor pointer points to a list with
a single item instead of meaning that our static head element doesn't point to
any list items.

Original patch by Chris, with significant mods and fixes by Andy and Zach.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andy Grover <andy.grover@oracle.com>
Signed-off-by: Zach Brown <zach.brown@oracle.com>
2010-09-08 18:15:23 -07:00
Andy Grover fc24f78085 RDS/IB: Remove ib_recv_unmap_page()
All it does is call unmap_sg(), so just call that directly.

The comment above unmap_page also may be incorrect, so we
shouldn't hold on to it, either.

Signed-off-by: Andy Grover <andy.grover@oracle.com>
2010-09-08 18:15:22 -07:00