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  1. 28 3月, 2012 1 次提交
  3. 27 3月, 2012 3 次提交
  5. 26 3月, 2012 1 次提交
  7. 24 3月, 2012 1 次提交
    • H
      poll: add poll_requested_events() and poll_does_not_wait() functions · 626cf236
      由 Hans Verkuil 提交于 
      In some cases the poll() implementation in a driver has to do different
things depending on the events the caller wants to poll for.  An example
is when a driver needs to start a DMA engine if the caller polls for
POLLIN, but doesn't want to do that if POLLIN is not requested but instead
only POLLOUT or POLLPRI is requested.  This is something that can happen
in the video4linux subsystem among others.

Unfortunately, the current epoll/poll/select implementation doesn't
provide that information reliably.  The poll_table_struct does have it: it
has a key field with the event mask.  But once a poll() call matches one
or more bits of that mask any following poll() calls are passed a NULL
poll_table pointer.

Also, the eventpoll implementation always left the key field at ~0 instead
of using the requested events mask.

This was changed in eventpoll.c so the key field now contains the actual
events that should be polled for as set by the caller.

The solution to the NULL poll_table pointer is to set the qproc field to
NULL in poll_table once poll() matches the events, not the poll_table
pointer itself.  That way drivers can obtain the mask through a new
poll_requested_events inline.

The poll_table_struct can still be NULL since some kernel code calls it
internally (netfs_state_poll() in ./drivers/staging/pohmelfs/netfs.h).  In
that case poll_requested_events() returns ~0 (i.e.  all events).

Very rarely drivers might want to know whether poll_wait will actually
wait.  If another earlier file descriptor in the set already matched the
events the caller wanted to wait for, then the kernel will return from the
select() call without waiting.  This might be useful information in order
to avoid doing expensive work.

A new helper function poll_does_not_wait() is added that drivers can use
to detect this situation.  This is now used in sock_poll_wait() in
include/net/sock.h.  This was the only place in the kernel that needed
this information.

Drivers should no longer access any of the poll_table internals, but use
the poll_requested_events() and poll_does_not_wait() access functions
instead.  In order to enforce that the poll_table fields are now prepended
with an underscore and a comment was added warning against using them
directly.

This required a change in unix_dgram_poll() in unix/af_unix.c which used
the key field to get the requested events.  It's been replaced by a call
to poll_requested_events().

For qproc it was especially important to change its name since the
behavior of that field changes with this patch since this function pointer
can now be NULL when that wasn't possible in the past.

Any driver accessing the qproc or key fields directly will now fail to compile.

Some notes regarding the correctness of this patch: the driver's poll()
function is called with a 'struct poll_table_struct *wait' argument.  This
pointer may or may not be NULL, drivers can never rely on it being one or
the other as that depends on whether or not an earlier file descriptor in
the select()'s fdset matched the requested events.

There are only three things a driver can do with the wait argument:

1) obtain the key field:

	events = wait ? wait->key : ~0;

   This will still work although it should be replaced with the new
   poll_requested_events() function (which does exactly the same).
   This will now even work better, since wait is no longer set to NULL
   unnecessarily.

2) use the qproc callback. This could be deadly since qproc can now be
   NULL. Renaming qproc should prevent this from happening. There are no
   kernel drivers that actually access this callback directly, BTW.

3) test whether wait == NULL to determine whether poll would return without
   waiting. This is no longer sufficient as the correct test is now
   wait == NULL || wait->_qproc == NULL.

   However, the worst that can happen here is a slight performance hit in
   the case where wait != NULL and wait->_qproc == NULL. In that case the
   driver will assume that poll_wait() will actually add the fd to the set
   of waiting file descriptors. Of course, poll_wait() will not do that
   since it tests for wait->_qproc. This will not break anything, though.

   There is only one place in the whole kernel where this happens
   (sock_poll_wait() in include/net/sock.h) and that code will be replaced
   by a call to poll_does_not_wait() in the next patch.

   Note that even if wait->_qproc != NULL drivers cannot rely on poll_wait()
   actually waiting. The next file descriptor from the set might match the
   event mask and thus any possible waits will never happen.
Signed-off-by: NHans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: NJonathan Corbet <corbet@lwn.net>
Reviewed-by: NAl Viro <viro@zeniv.linux.org.uk>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: NHans de Goede <hdegoede@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      626cf236
  9. 23 3月, 2012 10 次提交
    • A
      bonding: remove entries for master_ip and vlan_ip and query devices instead · eaddcd76
      由 Andy Gospodarek 提交于 
      The following patch aimed to resolve an issue where secondary, tertiary,
etc. addresses added to bond interfaces could overwrite the
bond->master_ip and vlan_ip values.

        commit 917fbdb3
        Author: Henrik Saavedra Persson <henrik.e.persson@ericsson.com>
        Date:   Wed Nov 23 23:37:15 2011 +0000

            bonding: only use primary address for ARP

That patch was good because it prevented bonds using ARP monitoring from
sending frames with an invalid source IP address.  Unfortunately, it
didn't always work as expected.

When using an ioctl (like ifconfig does) to set the IP address and
netmask, 2 separate ioctls are actually called to set the IP and netmask
if the mask chosen doesn't match the standard mask for that class of
address.  The first ioctl did not have a mask that matched the one in
the primary address and would still cause the device address to be
overwritten.  The second ioctl that was called to set the mask would
then detect as secondary and ignored, but the damage was already done.

This was not an issue when using an application that used netlink
sockets as the setting of IP and netmask came down at once.  The
inconsistent behavior between those two interfaces was something that
needed to be resolved.

While I was thinking about how I wanted to resolve this, Ralf Zeidler
came with a patch that resolved this on a RHEL kernel by keeping a full
shadow of the entries in dev->ifa_list for the bonding device and vlan
devices in the bonding driver.  I didn't like the duplication of the
list as I want to see the 'bonding' struct and code shrink rather than
grow, but liked the general idea.

As the Subject indicates this patch drops the master_ip and vlan_ip
elements from the 'bonding' and 'vlan_entry' structs, respectively.
This can be done because a device's address-list is now traversed to
determine the optimal source IP address for ARP requests and for checks
to see if the bonding device has a particular IP address.  This code
could have all be contained inside the bonding driver, but it made more
sense to me to EXPORT and call inet_confirm_addr since it did exactly
what was needed.

I tested this and a backported patch and everything works as expected.
Ralf also helped with verification of the backported patch.

Thanks to Ralf for all his help on this.

v2: Whitespace and organizational changes based on suggestions from Jay
Vosburgh and Dave Miller.

v3: Fixup incorrect usage of rcu_read_unlock based on Dave Miller's
suggestion.
Signed-off-by: NAndy Gospodarek <andy@greyhouse.net>
CC: Ralf Zeidler <ralf.zeidler@nsn.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      eaddcd76
    • R
      netfilter: remove forward module param confusion. · 523f610e
      由 Rusty Russell 提交于 
      It used to be an int, and it got changed to a bool parameter at least
7 years ago.  It happens that NF_ACCEPT and NF_DROP are 0 and 1, so
this works, but it's unclear, and the check that it's in range is not
required.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NRusty Russell <rusty@rustcorp.com.au>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      523f610e
    • P
      netfilter: nf_conntrack: permanently attach timeout policy to conntrack · 60b5f8f7
      由 Pablo Neira Ayuso 提交于 
      We need to permanently attach the timeout policy to the conntrack,
otherwise we may apply the custom timeout policy inconsistently.

Without this patch, the following example:

 nfct timeout add test inet icmp timeout 100
 iptables -I PREROUTING -t raw -p icmp -s 1.1.1.1 -j CT --timeout test

Will only apply the custom timeout policy to outgoing packets from
1.1.1.1, but not to reply packets from 2.2.2.2 going to 1.1.1.1.

To fix this issue, this patch modifies the current logic to attach the
timeout policy when the first packet is seen (which is when the
conntrack entry is created). Then, we keep using the attached timeout
policy until the conntrack entry is destroyed.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      60b5f8f7
    • P
      netfilter: xt_CT: fix assignation of the generic protocol tracker · eeb4cb95
      由 Pablo Neira Ayuso 提交于 
      `iptables -p all' uses 0 to match all protocols, while the conntrack
subsystem uses 255. We still need `-p all' to attach the custom
timeout policies for the generic protocol tracker.

Moreover, we may use `iptables -p sctp' while the SCTP tracker is
not loaded. In that case, we have to default on the generic protocol
tracker.

Another possibility is `iptables -p ip' that should be supported
as well. This patch makes sure we validate all possible scenarios.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      eeb4cb95
    • P
      netfilter: xt_CT: missing rcu_read_lock section in timeout assignment · 1ac0bf99
      由 Pablo Neira Ayuso 提交于 
      Fix a dereference to pointer without rcu_read_lock held.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      1ac0bf99
    • P
      netfilter: cttimeout: fix dependency with l4protocol conntrack module · c1ebd7df
      由 Pablo Neira Ayuso 提交于 
      This patch introduces nf_conntrack_l4proto_find_get() and
nf_conntrack_l4proto_put() to fix module dependencies between
timeout objects and l4-protocol conntrack modules.

Thus, we make sure that the module cannot be removed if it is
used by any of the cttimeout objects.
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      c1ebd7df
    • S
      xfrm: Access the replay notify functions via the registered callbacks · 1265fd61
      由 Steffen Klassert 提交于 
      We call the wrong replay notify function when we use ESN replay
handling. This leads to the fact that we don't send notifications
if we use ESN. Fix this by calling the registered callbacks instead
of xfrm_replay_notify().
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1265fd61
    • S
      xfrm: Remove unused xfrm_state from xfrm_state_check_space · 26b2072e
      由 Steffen Klassert 提交于 
      The xfrm_state argument is unused in this function, so remove it.
Also the name xfrm_state_check_space does not really match what this
function does. It actually checks if we have enough head and tailroom
on the skb. So we rename the function to xfrm_skb_check_space.
Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      26b2072e
    • D
      RDS: use gfp flags from caller in conn_alloc() · f0229eaa
      由 Dan Carpenter 提交于 
      We should be using the gfp flags the caller specified here, instead of
GFP_KERNEL.  I think this might be a bugfix, depending on the value of
"sock->sk->sk_allocation" when we call rds_conn_create_outgoing() in
rds_sendmsg().  Otherwise, it's just a cleanup.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NVenkat Venkatsubra <venkat.x.venkatsubra@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      f0229eaa
    • D
      netlabel: use GFP flags from caller instead of GFP_ATOMIC · 64b5fad5
      由 Dan Carpenter 提交于 
      This function takes a GFP flags as a parameter, but they are never used.
We don't take a lock in this function so there is no reason to prefer
GFP_ATOMIC over the caller's GFP flags.

There is only one caller, cipso_v4_map_cat_rng_ntoh(), and it passes
GFP_ATOMIC as the GFP flags so this doesn't change how the code works.
It's just a cleanup.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      64b5fad5
  11. 22 3月, 2012 3 次提交
  13. 21 3月, 2012 9 次提交
  15. 20 3月, 2012 7 次提交
  17. 17 3月, 2012 3 次提交
  19. 16 3月, 2012 2 次提交