Joonwoo Park [Mon, 26 Nov 2007 15:31:24 +0000 (23:31 +0800)]
[IPV4] fib_hash: kmalloc + memset conversion to kzalloc
fib_hash: kmalloc + memset conversion to kzalloc
fix to avoid memset entirely.
Signed-off-by: Joonwoo Park <joonwpark81@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Joonwoo Park [Mon, 26 Nov 2007 15:29:32 +0000 (23:29 +0800)]
[IPV4] fib_semantics: kmalloc + memset conversion to kzalloc
fib_semantics: kmalloc + memset conversion to kzalloc
fix to avoid memset entirely.
Signed-off-by: Joonwoo Park <joonwpark81@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Joonwoo Park [Mon, 26 Nov 2007 15:23:21 +0000 (23:23 +0800)]
[IPSEC]: kmalloc + memset conversion to kzalloc
2007/11/26, Patrick McHardy <kaber@trash.net>:
> How about also switching vmalloc/get_free_pages to GFP_ZERO
> and getting rid of the memset entirely while you're at it?
>
xfrm_hash: kmalloc + memset conversion to kzalloc
fix to avoid memset entirely.
Signed-off-by: Joonwoo Park <joonwpark81@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Mon, 26 Nov 2007 12:17:38 +0000 (20:17 +0800)]
[TCP]: Move FRTO checks out from write queue abstraction funcs
Better place exists in update_send_head (other non-queue related
adjustments are done there as well) which is the only caller of
tcp_advance_send_head (now that the bogus call from mtu_probe is
gone).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Mon, 26 Nov 2007 12:12:58 +0000 (20:12 +0800)]
[NET]: Make macro to specify the ptype_base size
Currently this size is 16, but as the comment says this
is so only because all the chains (except one) has the
length 1. I think, that some day this may change, so
growing this hash will be much easier.
Besides, symbolic names are read better than magic constants.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Mon, 26 Nov 2007 12:10:50 +0000 (20:10 +0800)]
[NET]: Name magic constants in sock_wake_async()
The sock_wake_async() performs a bit different actions
depending on "how" argument. Unfortunately this argument
ony has numerical magic values.
I propose to give names to their constants to help people
reading this function callers understand what's going on
without looking into this function all the time.
I suppose this is 2.6.25 material, but if it's not (or the
naming seems poor/bad/awful), I can rework it against the
current net-2.6 tree.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:14:15 +0000 (22:14 -0200)]
[DCCP]: Add support for abortive release
This continues from the previous patch and adds support for actively aborting
a DCCP connection, using a Reset Code 2, "Aborted" to inform the peer of an
abortive release.
I have tried this in various client/server settings and it works as expected.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Mon, 17 Dec 2007 00:06:03 +0000 (16:06 -0800)]
[DCCP]: Check for unread data on close
This removes one FIXME with regard to close when there is still unread data.
The mechanism is implemented similar to TCP: with regard to DCCP-specifics,
a Reset with Code 2, "Aborted" is sent to the peer.
This corresponds in part to RFC 4340, 8.1.1 and 8.1.5.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:12:06 +0000 (22:12 -0200)]
[CCID2]: Remove misleading comment
This removes a comment which identifies an `issue' with dccp_write_xmit() where there is none.
The comment assumes it is possible that a packet is sent between the calls to
I think that this is impossible, since dccp_write_xmit() is always called under lock:
* when called as dccp_write_xmit(sk, 1) from dccp_send_close(), the socket is locked
(see code comment above dccp_send_close());
* when called as dccp_write_xmit(sk, 0) from dccp_send_msg(), it is after lock_sock() has been called;
* when called as dccp_write_xmit(sk, 0) from dccp_write_xmit_timer(), bh_lock_sock() has been called
and the if/else statement has made sure that sk_lock.owner is not set;
* there are no other places where dccp_write_xmit() is called.
Furthermore, the debug statement for printing the sequence number of the packet just sent has been
removed, since the entire list is being printed anyway and so the entry of that number appears last.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:10:29 +0000 (22:10 -0200)]
[CCID2]: Remove redundant ack-counting variable
The code used two different variables to count Acks, one of them redundant.
This patch reduces the number of Ack counters to one.
The type of the Ack counter has also been changed to u32 (twice the range of int);
and the variable has been renamed into `packets_acked' - for consistency with
RFC 3465 (and similarly named variables are used by TCP and SCTP).
Lastly, a slightly less aggressive `maxincr' increment is used (for even Ack Ratios,
maxincr was Ack Ratio/2 + 1 instead of Ack Ratio/2).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
This removes the synchronisation variable `ccid2hctx_sendwait', which is set to 1
when the CCID2 sender may send a new packet, and which is set to 0 otherwise
The variable is redundant, since it is only used in combination with the hc_tx_send_packet/
hc_tx_packet_sent function pair. Both functions are called under socket lock, so the
following happens when the CCID2 may send a new packet:
* it sets sendwait = 1 in tx_send_packet and returns 0;
* the subsequent call to tx_packet_sent clears the sendwait flag;
* since tx_send_packet returns 0 if and only if sendwait == 1, the BUG_ON condition
in tx_packet_sent is never satisfied, since that function is never called when
tx_send_packet returns a value different from 0 (cf. dccp_write_xmit);
* the call to tx_packet_sent clears the flag so that the condition "!sendwait" is
true the next time tx_packet_sent is called.
In other words, it is sufficient to just return 0 / not-0 to synchronise tx_send_packet
and tx_packet_sent -- which is what the patch does.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:08:27 +0000 (22:08 -0200)]
[CCID2]: Redundant debugging output
This reduces the amount of redundant debugging messages:
* pipe/cwnd are printed in both tx_send_packet() and tx_packet_sent().
Both functions are called immediately after one another, so one occurrence is sufficient.
* Since tx_packet_sent() prints pipe/cwnd already, the second printk for pipe is redundant.
* In tx_packet_sent() the check_sanity function is called twice (at the begin and at the end).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:06:52 +0000 (22:06 -0200)]
[CCID2]: Replace pipe assignment-function with assignment
The function ccid2_change_pipe only does an assignment. This patch simplifies the code by
replacing the function with the assignment it performs.
Furthermore, the type of pipe is promoted from `signed' to unsigned (increasing the range).
As a result, a BUG_ON test for negative values now becomes obsolete (for safety not removed,
but replaced with a less annoying `DCCP_BUG').
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:05:51 +0000 (22:05 -0200)]
[CCID2]: Replace cwnd assignment-function with assignment
The current function ccid2_change_cwnd in effect makes only an assignment, as
the test whether cwnd has reached 0 is only required when cwnd is halved.
This patch simplifies the code by replacing the function with the assignment
it performs.
Furthermore, since ssthresh derives from cwnd and appears in many assignments and
comparisons, the type of ssthresh has also been changed to match that of cwnd.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:04:35 +0000 (22:04 -0200)]
[CCID2]: Replace read-only variable with constant
This replaces the field member `numdupack', which was used as a read-only
constant in the code, with a #define.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 25 Nov 2007 00:01:56 +0000 (22:01 -0200)]
[CCID2]: Remove unused variable
This removes a variable `ccid2hctx_sent' which is incremented but
never referenced/read (i.e., dead code).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 23:58:33 +0000 (21:58 -0200)]
[CCID2]: Disable broken Ack Ratio adaptation algorithm
This comments out a problematic section comprising a half-finished algorithm:
- The variable `ccid2hctx_ackloss' is never initialised to a value different from 0 and
hence in fact is a read-only constant.
- The `arsent' variable counts packets other than Acks (it is incremented for every packet),
and there is no test for Ack Loss.
- The concept of counting Acks as such leads to a complex calculation, and the calculation
at the moment is inconsistent with this concept.
The problem is that the number of Acks - rather than the number of windows - is counted,
which leads to a complex (cubic/quadratic) expression - this is not even implemented.
In its current state, the commented-out algorithm interfers with normal processing by
changing Ack Ratio incorrectly, and at the wrong times.
A new algorithm is necessary, which will not necessarily use the same variables as used by
the unfinished one; hence the old variables have been removed.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 23:44:30 +0000 (21:44 -0200)]
[CCID2]: Larger initial windows also for CCID2
RFC 4341, sec. 5 states that "The cwnd parameter is initialized to at most
four packets for new connections, following the rules from [RFC3390]", which
is implemented by this patch.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 23:40:24 +0000 (21:40 -0200)]
[CCID2]: Deadlock and spurious timeouts when Ack Ratio > cwnd
This patch removes a bug in the current code. I agree with Andrea's comment
that there is a problem here but the way it is treated does not fix it.
The problem is that whenever Ack Ratio > cwnd, starvation/deadlock occurs:
* the receiver will not send an Ack until (Ack Ratio - cwnd) data packets
have arrived;
* the sender will not send any data packet before the receipt of an Ack
advances the send window.
The only way that the connection then progresses was via RTO timeout. In one
extreme case (bulk transfer), it was observed that this happened for every single
packet; i.e. hundreds of packets, each a RTO timeout of 1..3 seconds apart:
a transfer which normally would take a fraction of a second thus grew to
several minutes.
The solution taken by this approach is to observe the relation
"Ack Ratio <= cwnd"
by using the constraint (1) from RFC 4341, 6.1.2; i.e. set
Ack Ratio = ceil(cwnd / 2)
and update it whenever either Ack Ratio or cwnd change. This ensures that
the deadlock problem can not arise.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 23:32:53 +0000 (21:32 -0200)]
[CCID2]: Don't assign negative values to Ack Ratio
Since it makes not sense to assign negative values to Ack Ratio, this
patch disallows this possibility.
As a consequence, a Bug test for negative Ack Ratio values becomes obsolete.
Furthermore, a check against overflow (as Ack Ratio may not exceed 2 bytes,
due to RFC 4340, 11.3) has been added.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 22:43:59 +0000 (20:43 -0200)]
[CCID2]: Fix sequence number arithmetic/comparisons
This replaces use of normal subtraction with modulo-48 subtraction.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sat, 24 Nov 2007 22:37:48 +0000 (20:37 -0200)]
[CCID2]: Bug in reading Ack Vectors
In CCID2 the receiver-history is sorted in ascending order of sequence number,
but the processing of received Ack Vectors requires the list traversal in the
opposite direction.
The current code has a bug in this regard: the list traversal is upwards. As a
consequence, only Ack Vectors with a run length of 1 will pass, in all other
Ack Vectors the remaining (acked) sequence numbers are missed, and may later
falsely be identified as lost.
Note: This bug is only visible when Ack Ratio > 1, since otherwise the run
lengths of Ack Vectors are 0.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Sun, 30 Dec 2007 12:19:31 +0000 (04:19 -0800)]
[ACKVEC]: Reduce length of identifiers
This is reduces the length of the struct ackvec/ackvec_record fields. It is
a purely text-based replacement:
s#dccpavr_#avr_#g;
s#dccpav_#av_#g;
and increases readability somewhat.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Mon, 26 Nov 2007 15:34:54 +0000 (23:34 +0800)]
[PCOUNTER] Fix build error without CONFIG_SMP
I keep getting this build error and couldn't find anyone fixing
it in archives. ...Maybe all net developers except me build
just SMP kernels :-).
In file included from include/net/sock.h:50,
from ipc/mqueue.c:35:
include/linux/pcounter.h: In function 'pcounter_add':
include/linux/pcounter.h:87: error: 'struct pcounter' has no
member named 'value'
make[1]: *** [ipc/mqueue.o] Error 1
make: *** [ipc] Error 2
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Fri, 23 Nov 2007 13:28:44 +0000 (21:28 +0800)]
[IPV6]: Correct the comment concerning inetsw6 table
It seems that net/ipv6/af_inet6.c was copied from net/ipv4/af_inet.c,
but one comment was not fixed.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Fri, 23 Nov 2007 12:30:01 +0000 (20:30 +0800)]
[UNIX] Move the unix sock iterators in to proper place
The first_unix_socket() and next_unix_sockets() are now used
in proc file and in forall_unix_socets macro only.
The forall_unix_sockets is not used in this file at all so
remove it. After this move the helpers to where they really
belong, i.e. closer to proc code under the #ifdef CONFIG_PROC_FS
option.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 12:14:31 +0000 (10:14 -0200)]
[DCCP]: Update documentation on ioctls
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 12:13:53 +0000 (10:13 -0200)]
[DCCP]: Ignore Ack Vectors / Elapsed Time on DCCP-Request also
Small update with regard to RFC 4340 (references added as documentation):
on Requests, Ack Vectors / Elapsed Time should be ignored.
Length handling of Elapsed Time also simplified.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 12:11:52 +0000 (10:11 -0200)]
[DCCP]: Remove redundant dependency on IP_DCCP
This cleans up the consequences of an earlier patch which
introduced the `if IP_DCCP' clause into net/dccp/Kconfig.
The CCID Kconfig menu is sourced within this clause; as a
consequence, all tests of type `depends on IP_DCCP' are now
redundant.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 12:09:56 +0000 (10:09 -0200)]
[DCCP]: Promote CCID2 as default CCID
This patch addresses the following problems:
1. DCCP relies for its proper functioning on having at least one CCID module
enabled (as in TCP plugable congestion control). Currently it is possible to
disable both CCIDs and thus leave the DCCP module in a compiled, but entirely
non-functional state: no sockets can be created when no CCID is available.
Furthermore, the protocol is (again like TCP) not intended to be used without
CCIDs. Last, a non-empty CCID list is needed for doing CCID feature negotiation.
2. Internally the default CCID that is advertised by the Linux host is set to CCID2
(DCCPF_INITIAL_CCID in include/linux/dccp.h). Disabling CCID2 in the Kconfig
menu without changing the defaults leads to a failure `module not found' when
trying to load the dccp module (which internally tries to load the default CCID).
3. The specification (RFC 4340, sec. 10) treats CCID2 somewhat like a
`minimum common denominator'; the specification says that:
* "New connections start with CCID 2 for both endpoints"
* "A DCCP implementation intended for general use, such as an implementation in a
general-purpose operating system kernel, SHOULD implement at least CCID 2.
The intent is to make CCID 2 broadly available for interoperability [...]"
Providing CCID2 as minimum-required CCID (like Reno/Cubic in TCP) thus seems reasonable.
Hence this patch automatically selects CCID2 when DCCP is enabled. Documentation also added.
Discussions with Ian McDonald on this subject are gratefully acknowledged.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 12:00:17 +0000 (10:00 -0200)]
[DCCP]: Update documentation
This updates the DCCP documentation, following input from Ian McDonald,
clarifiying the status of DCCP, and adding a note about the test tree.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Wed, 21 Nov 2007 11:56:48 +0000 (09:56 -0200)]
[DCCP]: Honour and make use of shutdown option set by user
This extends the DCCP socket API by honouring any shutdown(2) option set by the user.
The behaviour is, as much as possible, made consistent with the API for TCP's shutdown.
This patch exploits the information provided by the user via the socket API to reduce
processing costs:
* if the read end is closed (SHUT_RD), it is not necessary to deliver to input CCID;
* if the write end is closed (SHUT_WR), the same idea applies, but with a difference -
as long as the TX queue has not been drained, we need to receive feedback to keep
congestion-control rates up to date. Hence SHUT_WR is honoured only after the last
packet (under congestion control) has been sent;
* although SHUT_RDWR seems nonsensical, it is nevertheless supported in the same manner
as for TCP (and agrees with test for SHUTDOWN_MASK in dccp_poll() in net/dccp/proto.c).
Furthermore, most of the code already honours the sk_shutdown flags (dccp_recvmsg() for
instance sets the read length to 0 if SHUT_RD had been called); CCID handling is now added
to this by the present patch.
There will also no longer be any delivery when the socket is in the final stages, i.e. when
one of dccp_close(), dccp_fin(), or dccp_done() has been called - which is fine since at
that stage the connection is its final stages.
Motivation and background are on http://www.erg.abdn.ac.uk/users/gerrit/dccp/notes/shutdown
A FIXME has been added to notify the other end if SHUT_RD has been set (RFC 4340, 11.7).
Note: There is a comment in inet_shutdown() in net/ipv4/af_inet.c which asks to "make
sure the socket is a TCP socket". This should probably be extended to mean
`TCP or DCCP socket' (the code is also used by UDP and raw sockets).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Tue, 20 Nov 2007 23:56:37 +0000 (21:56 -0200)]
[DCCP]: Make PARTOPEN an autonomous state
This decouples PARTOPEN from TCP-specific stream-states.
It thus addresses the FIXME.
The code has been checked with regard to dependency on PARTOPEN and FIN_WAIT1
states (to which PARTOPEN previously was mapped): there is no difference, as
PARTOPEN is always referred to directly (i.e. not via the mapping to TCP
state).
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Tue, 20 Nov 2007 20:09:59 +0000 (18:09 -0200)]
[CCID3]: Inline for moving average
The moving average computation occurs so frequently in the CCID 3 code that
it merits an inline function of its own. This is uses a suggestion by
Arnaldo as per http://www.mail-archive.com/dccp@vger.kernel.org/msg01662.html
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Tue, 20 Nov 2007 20:01:59 +0000 (18:01 -0200)]
[CCID3]: Accurately determine idle & application-limited periods
This fixes/updates the handling of idle and application-limited periods in CCID3,
which currently is broken: there is no detection as to how long a sender has been
idle - there is only one flag which is toggled in between function calls.
Being obsolete now, the `idle' flag is removed.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Tue, 20 Nov 2007 20:00:39 +0000 (18:00 -0200)]
[CCID3]: Ignore trivial amounts of elapsed time
This patch fixes a previously undiscovered bug; the problem is in computing
the elapsed time as the time between `receiving' the packet (i.e. skb enters
CCID module) and sending feedback:
- there is no layer-processing, queueing, or delay involved,
- hence the elapsed time is in the order of 1 function call
- this is in the dimension of maximally 50..100usec
- which renders the use of elapsed time almost entirely useless.
The fix is simply to ignore such trivial amounts of elapsed time.
As a further advantage, the now useless elapsed_time field can be removed from
the socket, which reduces the socket structure by another four bytes.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Gerrit Renker [Tue, 20 Nov 2007 19:33:17 +0000 (17:33 -0200)]
[CCID3]: Revert use of MSS instead of s
This updates the CCID3 code with regard to two instances of using `MSS' in place of `s':
1. The RFC3390-based initial rate: both rfc3448bis as well as the Faster Restart
draft now consistently use `s' instead of MSS.
2. Now agrees with section 4.2 of rfc3448bis: "If the sender is ready to send data when
it does not yet have a round trip sample, the value of X is set to s bytes per
second, for segment size s [...]"
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: Ian McDonald <ian.mcdonald@jandi.co.nz> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
[NET]: Define infrastructure to keep 'inuse' changes in an efficent SMP/NUMA way.
Please look at the comment in there to see the rationale.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg [Fri, 16 Nov 2007 01:17:07 +0000 (02:17 +0100)]
mac80211: remove more forgotten code
Hopefully that's the rest. Seems I didn't do a very thorough job
removing the management interface.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ron Rindjunsky [Wed, 14 Nov 2007 17:57:38 +0000 (19:57 +0200)]
mac80211: adding 802.11n definitions in ieee80211.h
This patch adds several structs and definitions to ieee80211.h
to support 802.11n draft specifications.
As 802.11n depends on and extends the 802.11e standard in several issues,
there are also several definitions that belong to 802.11e.
Signed-off-by: Ron Rindjunsky <ron.rindjunsky@intel.com> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Helmut Schaa [Fri, 9 Nov 2007 15:26:09 +0000 (16:26 +0100)]
mac80211: Remove local->scan_flags
This patch removes all references to local->scan_flags as these are not
used anymore since the removal of prism2 ioctls.
Signed-off-by: Helmut Schaa <hschaa@suse.de> Signed-off-by: Jiri Benc <jbenc@suse.cz> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Johannes Berg [Fri, 9 Nov 2007 00:57:29 +0000 (01:57 +0100)]
mac80211: provide interface iterator for drivers
Sometimes drivers need to know which interfaces are associated with
their hardware. Rather than forcing those drivers to keep track of
the interfaces that were added, this adds an iteration function to
mac80211.
As it is intended to be used from the interface add/remove callbacks,
the iteration function may currently only be called under RTNL.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Tue, 20 Nov 2007 07:20:59 +0000 (23:20 -0800)]
[NET]: Compact sk_stream_mem_schedule() code
This function references sk->sk_prot->xxx for many times.
It turned out, that there's so many code in it, that gcc
cannot always optimize access to sk->sk_prot's fields.
After saving the sk->sk_prot on the stack and comparing
disassembled code, it turned out that the function became
~10 bytes shorter and made less dereferences (on i386 and
x86_64). Stack consumption didn't grow.
Besides, this patch drives most of this function into the
80 columns limit.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Benjamin Thery [Tue, 20 Nov 2007 07:18:16 +0000 (23:18 -0800)]
[NET]: Make netns cleanup to run in a separate queue
This patch adds a separate workqueue for cleaning up a network
namespace. If we use the keventd workqueue to execute cleanup_net(),
there is a problem to unregister devices in IPv6. Indeed the code
that cleans up also schedule work in keventd: as long as cleanup_net()
hasn't return, dst_gc_task() cannot run and as long as dst_gc_task() has
not run, there are still some references pending on the net devices and
cleanup_net() can not unregister and exit the keventd workqueue.
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com> Acked-by: Denis V. Lunev <den@openvz.org> Acked-By: Kirill Korotaev <dev@sw.ru> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Tue, 20 Nov 2007 06:43:37 +0000 (22:43 -0800)]
[PATCH] IPV4 : Move ip route cache flush (secret_rebuild) from softirq to workqueue
Every 600 seconds (ip_rt_secret_interval), a softirq flush of the
whole ip route cache is triggered. On loaded machines, this can starve
softirq for many seconds and can eventually crash.
This patch moves this flush to a workqueue context, using the worker
we intoduced in commit 39c90ece7565f5c47110c2fa77409d7a9478bd5b (IPV4:
Convert rt_check_expire() from softirq processing to workqueue.)
Also, immediate flushes (echo 0 >/proc/sys/net/ipv4/route/flush) are
using rt_do_flush() helper function, wich take attention to
rescheduling.
Next step will be to handle delayed flushes
("echo -1 >/proc/sys/net/ipv4/route/flush" or "ip route flush cache")
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Tue, 20 Nov 2007 06:38:33 +0000 (22:38 -0800)]
[RAW]: Consolidate proc interface.
Both ipv6/raw.c and ipv4/raw.c use the seq files to walk
through the raw sockets hash and show them.
The "walking" code is rather huge, but is identical in both
cases. The difference is the hash table to walk over and
the protocol family to check (this was not in the first
virsion of the patch, which was noticed by YOSHIFUJI)
Make the ->open store the needed hash table and the family
on the allocated raw_iter_state and make the start/next/stop
callbacks work with it.
This removes most of the code.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Denis V. Lunev [Tue, 20 Nov 2007 06:29:30 +0000 (22:29 -0800)]
[NET]: Make AF_UNIX per network namespace safe [v2]
Because of the global nature of garbage collection, and because of the
cost of per namespace hash tables unix_socket_table has been kept
global. With a filter added on lookups so we don't see sockets from
the wrong namespace.
Currently I don't fold the namesapce into the hash so multiple
namespaces using the same socket name will be guaranteed a hash
collision.
Changes from v1:
- fixed unix_seq_open
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Denis V. Lunev [Tue, 20 Nov 2007 06:28:35 +0000 (22:28 -0800)]
[NET]: Make AF_PACKET handle multiple network namespaces
This is done by making packet_sklist_lock and packet_sklist per
network namespace and adding an additional filter condition on
received packets to ensure they came from the proper network
namespace.
Changes from v1:
- prohibit to call inet_dgram_ops.ioctl in other than init_net
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
[NET]: Make the netlink methods in rtnetlink handle multiple network namespaces
After the previous prep work this just consists of removing checks
limiting the code to work in the initial network namespace, and
updating rtmsg_ifinfo so we can generate events for devices in
something other then the initial network namespace.
Referring to network other network devices like the IFLA_LINK
and IFLA_MASTER attributes do, gets interesting if those network
devices happen to be in other network namespaces. Currently
ifindex numbers are allocated globally so I have taken the path
of least resistance and not still report the information even
though the devices they are talking about are invisible.
If applications start getting confused or when ifindex
numbers become local to the network namespace we may need
to do something different in the future.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Denis V. Lunev <den@openz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Denis V. Lunev [Tue, 20 Nov 2007 06:26:51 +0000 (22:26 -0800)]
[NET]: Make rtnetlink infrastructure network namespace aware (v3)
After this patch none of the netlink callback support anything
except the initial network namespace but the rtnetlink infrastructure
now handles multiple network namespaces.
Changes from v2:
- IPv6 addrlabel processing
Changes from v1:
- no need for special rtnl_unlock handling
- fixed IPv6 ndisc
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Denis V. Lunev [Fri, 30 Nov 2007 13:21:31 +0000 (00:21 +1100)]
[NET]: Modify all rtnetlink methods to only work in the initial namespace (v2)
Before I can enable rtnetlink to work in all network namespaces I need
to be certain that something won't break. So this patch deliberately
disables all of the rtnletlink methods in everything except the
initial network namespace. After the methods have been audited this
extra check can be disabled.
Changes from v1:
- added IPv6 addrlabel protection
Signed-off-by: Denis V. Lunev <den@openvz.org> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[IPVS]: Create synced connections with their real state
With this patch the synced connections are created with their real state,
which can be changed on the next synchronizations if necessary. This way
on fail-over all the connections will be treated according to their actual
state, causing no scheduling problems (the active and the nonactive
connections have different weights in the schedulers).
The backwards compatibility is preserved and the existing tools will show
the true connection states even on the backup director.
Signed-off-by: Rumen G. Bogdanovski <rumen@voicecho.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
[IPVS]: Flag synced connections and expose them in proc
This patch labels the sync-created connections with IP_VS_CONN_F_SYNC
flag and creates /proc/net/ip_vs_conn_sync to enable monitoring of the
origin of the connections, if they are local or created by the
synchronization.
Signed-off-by: Rumen G. Bogdanovski <rumen@voicecho.com> Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
Michael Wu [Tue, 30 Oct 2007 20:50:05 +0000 (16:50 -0400)]
ieee80211: Add IEEE80211_MAX_FRAME_LEN to linux/ieee80211.h
This patch adds IEEE80211_MAX_FRAME_LEN which is useful for drivers trying
to determine how much to allocate for their RX buffers.
It also updates the comment on IEEE80211_MAX_DATA_LEN based on revisions
in 802.11e.
IEEE80211_MAX_FRAG_THRESHOLD and IEEE80211_MAX_RTS_THRESHOLD are also
revised due to the new maximum frame size.
Signed-off-by: Michael Wu <flamingice@sourmilk.net> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Mattias Nissler [Wed, 24 Oct 2007 21:30:36 +0000 (23:30 +0200)]
mac80211: Accept auto txpower setting
This changes the SIWTXPOWER ioctl to also accept a txpower setting of
"automatic". Since mac80211 currently cannot tell drivers to automatically
adjust tx power, we select the tx power level of the current channel. While
this is kind of a hack, it certainly saves some iwconfig users from headaches.
Signed-off-by: Mattias Nissler <mattias.nissler@gmx.de> Signed-off-by: John W. Linville <linville@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Sat, 17 Nov 2007 00:17:05 +0000 (16:17 -0800)]
[TCP]: Correct DSACK check placing
Previously one of the in-block skip branches was missing it.
Also, drop it from tail-fully-processed case because the next
iteration will do exactly the same thing, i.e., process the
SACK block that contains the DSACK information.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Sat, 17 Nov 2007 00:09:28 +0000 (16:09 -0800)]
[CAN]: Add documentation
This patch adds documentation for the PF_CAN protocol family.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Sat, 17 Nov 2007 00:07:41 +0000 (16:07 -0800)]
[CAN]: Add maintainer entries
This patch adds entries in the CREDITS and MAINTAINERS file for CAN.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Fri, 16 Nov 2007 23:56:08 +0000 (15:56 -0800)]
[CAN]: Add virtual CAN netdevice driver
This patch adds the virtual CAN bus (vcan) network driver.
The vcan device is just a loopback device for CAN frames, no
real CAN hardware is involved.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Fri, 16 Nov 2007 23:53:52 +0000 (15:53 -0800)]
[CAN]: Add broadcast manager (bcm) protocol
This patch adds the CAN broadcast manager (bcm) protocol.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Fri, 16 Nov 2007 23:53:09 +0000 (15:53 -0800)]
[CAN]: Add raw protocol
This patch adds the CAN raw protocol.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Fri, 16 Nov 2007 23:52:17 +0000 (15:52 -0800)]
[CAN]: Add PF_CAN core module
This patch adds the CAN core functionality but no protocols or drivers.
No protocol implementations are included here. They come as separate
patches. Protocol numbers are already in include/linux/can.h.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Oliver Hartkopp [Sun, 16 Dec 2007 23:59:24 +0000 (15:59 -0800)]
[CAN]: Allocate protocol numbers for PF_CAN
This patch adds a protocol/address family number, ARP hardware type,
ethernet packet type, and a line discipline number for the SocketCAN
implementation.
Signed-off-by: Oliver Hartkopp <oliver.hartkopp@volkswagen.de> Signed-off-by: Urs Thuermann <urs.thuermann@volkswagen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
Eric Dumazet [Fri, 16 Nov 2007 11:32:10 +0000 (03:32 -0800)]
[NET]: NET_CLS_ROUTE : convert ip_rt_acct to per_cpu variables
ip_rt_acct needs 4096 bytes per cpu to perform some accounting.
It is actually allocated as a single huge array [4096*NR_CPUS]
(rounded up to a power of two)
Converting it to a per cpu variable is wanted to :
- Save space on machines were num_possible_cpus() < NR_CPUS
- Better NUMA placement (each cpu gets memory on its node)
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Fri, 16 Nov 2007 03:50:37 +0000 (19:50 -0800)]
[TCP]: Rewrite SACK block processing & sack_recv_cache use
Key points of this patch are:
- In case new SACK information is advance only type, no skb
processing below previously discovered highest point is done
- Optimize cases below highest point too since there's no need
to always go up to highest point (which is very likely still
present in that SACK), this is not entirely true though
because I'm dropping the fastpath_skb_hint which could
previously optimize those cases even better. Whether that's
significant, I'm not too sure.
Currently it will provide skipping by walking. Combined with
RB-tree, all skipping would become fast too regardless of window
size (can be done incrementally later).
Previously a number of cases in TCP SACK processing fails to
take advantage of costly stored information in sack_recv_cache,
most importantly, expected events such as cumulative ACK and new
hole ACKs. Processing on such ACKs result in rather long walks
building up latencies (which easily gets nasty when window is
huge). Those latencies are often completely unnecessary
compared with the amount of _new_ information received, usually
for cumulative ACK there's no new information at all, yet TCP
walks whole queue unnecessary potentially taking a number of
costly cache misses on the way, etc.!
Since the inclusion of highest_sack, there's a lot information
that is very likely redundant (SACK fastpath hint stuff,
fackets_out, highest_sack), though there's no ultimate guarantee
that they'll remain the same whole the time (in all unearthly
scenarios). Take advantage of this knowledge here and drop
fastpath hint and use direct access to highest SACKed skb as
a replacement.
Effectively "special cased" fastpath is dropped. This change
adds some complexity to introduce better coveraged "fastpath",
though the added complexity should make TCP behave more cache
friendly.
The current ACK's SACK blocks are compared against each cached
block individially and only ranges that are new are then scanned
by the high constant walk. For other parts of write queue, even
when in previously known part of the SACK blocks, a faster skip
function is used (if necessary at all). In addition, whenever
possible, TCP fast-forwards to highest_sack skb that was made
available by an earlier patch. In typical case, no other things
but this fast-forward and mandatory markings after that occur
making the access pattern quite similar to the former fastpath
"special case".
DSACKs are special case that must always be walked.
The local to recv_sack_cache copying could be more intelligent
w.r.t DSACKs which are likely to be there only once but that
is left to a separate patch.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Fri, 16 Nov 2007 03:42:54 +0000 (19:42 -0800)]
[TCP]: Make lost retrans detection more self-contained
Highest_sack_end_seq is no longer calculated in the loop,
thus it can be pushed to the worker function altogether
making that function independent of the sacktag.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Fri, 16 Nov 2007 03:39:31 +0000 (19:39 -0800)]
[TCP]: non-FACK SACK follows conservative SACK loss recovery
Many assumptions that are true when no reordering or other
strange events happen are not a part of the RFC3517. FACK
implementation is based on such assumptions. Previously (before
the rewrite) the non-FACK SACK was basically doing fast rexmit
and then it times out all skbs when first cumulative ACK arrives,
which cannot really be called SACK based recovery :-).
RFC3517 SACK disables these things:
- Per SKB timeouts & head timeout entry to recovery
- Marking at least one skb while in recovery (RFC3517 does this
only for the fast retransmission but not for the other skbs
when cumulative ACKs arrive in the recovery)
- Sacktag's loss detection flavors B and C (see comment before
tcp_sacktag_write_queue)
This does not implement the "last resort" rule 3 of NextSeg, which
allows retransmissions also when not enough SACK blocks have yet
arrived above a segment for IsLost to return true [RFC3517].
The implementation differs from RFC3517 in these points:
- Rate-halving is used instead of FlightSize / 2
- Instead of using dupACKs to trigger the recovery, the number
of SACK blocks is used as FACK does with SACK blocks+holes
(which provides more accurate number). It seems that the
difference can affect negatively only if the receiver does not
generate SACK blocks at all even though it claimed to be
SACK-capable.
- Dupthresh is not a constant one. Dynamical adjustments include
both holes and sacked segments (equal to what FACK has) due to
complexity involved in determining the number sacked blocks
between highest_sack and the reordered segment. Thus it's will
be an over-estimate.
Implementation note:
tcp_clean_rtx_queue doesn't need a lost_cnt tweak because head
skb at that point cannot be SACKED_ACKED (nor would such
situation last for long enough to cause problems).
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Ilpo Järvinen [Fri, 16 Nov 2007 03:35:11 +0000 (19:35 -0800)]
[TCP]: Extend reordering detection to cover CA_Loss partially
This implements more accurately what is stated in sacktag's
overall comment:
"Both of these heuristics are not used in Loss state, when
we cannot account for retransmits accurately."
When CA_Loss state is entered, the state changer ensures that
undo_marker is only set if no TCPCB_RETRANS skbs were found,
thus having non-zero undo_marker in CA_Loss basically tells
that the R-bits still accurately reflect the current state
of TCP.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Thu, 15 Nov 2007 11:03:19 +0000 (03:03 -0800)]
[NET]: Move sock_valbool_flag to socket.c
The sock_valbool_flag() helper is used in setsockopt to
set or reset some flag on the sock. This helper is required
in the net/socket.c only, so move it there.
Besides, patch two places in sys_setsockopt() that repeat
this helper functionality manually.
Since this is not a bugfix, but a trivial cleanup, I
prepared this patch against net-2.6.25, but it also
applies (with a single offset) to the latest net-2.6.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Pavel Emelyanov [Thu, 15 Nov 2007 00:01:43 +0000 (16:01 -0800)]
[NET]: Use sockfd_lookup_light in the rest of the net/socket.c
Some time ago a sockfd_lookup_light was introduced and
most of the socket.c file was patched to use it. However
two routines were left - sys_sendto and sys_recvfrom.
Patch them as well, since this helper does exactly what
these two need.
Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
projects / linux-2.6 / log