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path: root/include/net/tcp.h
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2007-11-19[TCP] MTUprobe: fix potential sk_send_head corruptionIlpo Järvinen
When the abstraction functions got added, conversion here was made incorrectly. As a result, the skb may end up pointing to skb which got included to the probe skb and then was freed. For it to trigger, however, skb_transmit must fail sending as well. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-23[TCP]: Remove unneeded implicit type cast when calling tcp_minshall_update()Chuck Lever
The tcp_minshall_update() function is called in exactly one place, and is passed an unsigned integer for the mss_len argument. Make the sign of the argument match the sign of the passed variable in order to eliminate an unneeded implicit type cast and a mixed sign comparison in tcp_minshall_update(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Minor coding style fixup.David S. Miller
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Avoid clearing sacktag hint in trivial situationsIlpo Järvinen
There's no reason to clear the sacktag skb hint when small part of the rexmit queue changes. Account changes (if any) instead when fragmenting/collapsing. RTO/FRTO do not touch SACKED_ACKED bits so no need to discard SACK tag hint at all. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: clear_all_retrans_hints prefixed by tcp_Ilpo Järvinen
In addition, fix its function comment spacing. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
2007-10-10[TCP]: tcp_packets_out_inc to tcp_output.c (no callers elsewhere)Ilpo Järvinen
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Remove unnecessary wrapper tcp_packets_out_decIlpo Järvinen
Makes caller side more obvious, there's no need to have a wrapper for this oneliner! Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Move sack_ok access to obviously named funcs & cleanupIlpo Järvinen
Previously code had IsReno/IsFack defined as macros that were local to tcp_input.c though sack_ok field has user elsewhere too for the same purpose. This changes them to static inlines as preferred according the current coding style and unifies the access to sack_ok across multiple files. Magic bitops of sack_ok for FACK and DSACK are also abstracted to functions with appropriate names. Note: - One sack_ok = 1 remains but that's self explanary, i.e., it enables sack - Couple of !IsReno cases are changed to tcp_is_sack - There were no users for IsDSack => I dropped it Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Don't panic if S+L skb is detectedIlpo Järvinen
BUG_ON is an overkill. In fact, I was mislead by BUG_TRAP severity (equals to WARN_ON) which is much lower than BUG_ON's (that panics). Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Reduce sacked_out with reno when purging write_queueIlpo Järvinen
Previously TCP had a transitional state during which reno counted segments that are already below the current window into sacked_out, which is now prevented. In addition, re-try now the unconditional S+L skb catching. This approach conservatively calls just remove_sack and leaves reset_sack() calls alone. The best solution to the whole problem would be to first calculate the new sacked_out fully (this patch does not move reno_sack_reset calls from original sites and thus does not implement this). However, that would require very invasive change to fastretrans_alert (perhaps even slicing it to two halves). Alternatively, all callers of tcp_packets_in_flight (i.e., users that depend on sacked_out) should be postponed until the new sacked_out has been calculated but it isn't any simpler alternative. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Left out sync->verify (the new meaning of it) & definifyIlpo Järvinen
Left_out was dropped a while ago, thus leaving verifying consistency of the "left out" as only task for the function in question. Thus make it's name more appropriate. In addition, it is intentionally converted to #define instead of static inline because the location of the invariant failure is the most important thing to have if this ever triggers. I think it would have been helpful e.g. in this case where the location of the failure point had to be based on some quesswork: http://lkml.org/lkml/2007/5/2/464 ...Luckily the guesswork seems to have proved to be correct. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Add tcp_left_out(tp) "back" to get cleaner looking linesIlpo Järvinen
tp->left_out got removed but nothing came to replace it back then (users just did addition by themselves), so add function for users now. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Tighten tcp_sock's belt, drop left_outIlpo Järvinen
It is easily calculable when needed and user are not that many after all. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Add tcp_dec_pcount_approx int variantIlpo Järvinen
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-10-10[TCP]: Move code from tcp_ecn.h to tcp*.c and tcp.h & remove itIlpo Järvinen
No other users exist for tcp_ecn.h. Very few things remain in tcp.h, for most TCP ECN functions callers reside within a single .c file and can be placed there. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-09-28[TCP]: Fix MD5 signature handling on big-endian.David S. Miller
Based upon a report and initial patch by Peter Lieven. tcp4_md5sig_key and tcp6_md5sig_key need to start with the exact same members as tcp_md5sig_key. Because they are both cast to that type by tcp_v{4,6}_md5_do_lookup(). Unfortunately tcp{4,6}_md5sig_key use a u16 for the key length instead of a u8, which is what tcp_md5sig_key uses. This just so happens to work by accident on little-endian, but on big-endian it doesn't. Instead of casting, just place tcp_md5sig_key as the first member of the address-family specific structures, adjust the access sites, and kill off the ugly casts. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-08-02[TCP]: Invoke tcp_sendmsg() directly, do not use inet_sendmsg().David S. Miller
As discovered by Evegniy Polyakov, if we try to sendmsg after a connection reset, we can do incredibly stupid things. The core issue is that inet_sendmsg() tries to autobind the socket, but we should never do that for TCP. Instead we should just go straight into TCP's sendmsg() code which will do all of the necessary state and pending socket error checks. TCP's sendpage already directly vectors to tcp_sendpage(), so this merely brings sendmsg() in line with that. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-31[TCP]: congestion control API pass RTT in microsecondsStephen Hemminger
This patch changes the API for the callback that is done after an ACK is received. It solves a couple of issues: * Some congestion controls want higher resolution value of RTT (controlled by TCP_CONG_RTT_SAMPLE flag). These don't really want a ktime, but all compute a RTT in microseconds. * Other congestion control could use RTT at jiffies resolution. To keep API consistent the units should be the same for both cases, just the resolution should change. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-07-18[TCP]: remove unused argument to cong_avoid opStephen Hemminger
None of the existing TCP congestion controls use the rtt value pased in the ca_ops->cong_avoid interface. Which is lucky because seq_rtt could have been -1 when handling a duplicate ack. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-31[TCP]: Consolidate checking for tcp orphan count being too big.Pavel Emelianov
tcp_out_of_resources() and tcp_close() perform the same checking of number of orphan sockets. Move this code into common place. Signed-off-by: Pavel Emelianov <xemul@openvz.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-05-03[TCP]: Use S+L catcher only with SACK for nowIlpo Järvinen
TCP has a transitional state when SACK is not in use during which this invariant is temporarily broken. Without SACK, tcp_clean_rtx_queue does not decrement sacked_out. Therefore calls to tcp_sync_left_out before sacked_out is again corrected by tcp_fastretrans_alert can trigger this trap as sacked_out still has couple of segments that are already out of window. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-30[TCP] FRTO: RFC4138 allows Nagle override when new data must be sentIlpo Järvinen
This is a corner case where less than MSS sized new data thingie is awaiting in the send queue. For F-RTO to work correctly, a new data segment must be sent at certain point or F-RTO cannot be used at all. RFC4138 allows overriding of Nagle at that point. Implementation uses frto_counter states 2 and 3 to distinguish when Nagle override is needed. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-30[TCP]: Catch skb with S+L bugs earlierIlpo Järvinen
SACKED_ACKED and LOST are mutually exclusive with SACK, thus having their sum larger than packets_out is bug with SACK. Eventually these bugs trigger traps in the tcp_clean_rtx_queue with SACK but it's much more informative to do this here. Non-SACK TCP, however, could get more than packets_out duplicate ACKs which each increment sacked_out, so it makes sense to do this kind of limitting for non-SACK TCP but not for SACK enabled one. Perhaps the author had the opposite in mind but did the logic accidently wrong way around? Anyway, the sacked_out incrementer code for non-SACK already deals this issue before calling sync_left_out so this trapping can be done unconditionally. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Congestion control API update.Stephen Hemminger
Do some simple changes to make congestion control API faster/cleaner. * use ktime_t rather than timeval * merge rtt sampling into existing ack callback this means one indirect call versus two per ack. * use flags bits to store options/settings Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Sed magic converts func(sk, tp, ...) -> func(sk, ...)Ilpo Järvinen
This is (mostly) automated change using magic: sed -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e '/struct sock \*sk/ N' -e 's|struct sock \*sk,[\n\t ]*struct tcp_sock \*tp\([^{]*\n{\n\)| struct sock \*sk\1\tstruct tcp_sock *tp = tcp_sk(sk);\n|g' -e 's|struct sock \*sk, struct tcp_sock \*tp| struct sock \*sk|g' -e 's|sk, tp\([^-]\)|sk\1|g' Fixed four unused variable (tp) warnings that were introduced. In addition, manually added newlines after local variables and tweaked function arguments positioning. $ gcc --version gcc (GCC) 4.1.1 20060525 (Red Hat 4.1.1-1) ... $ codiff -fV built-in.o.old built-in.o.new net/ipv4/route.c: rt_cache_flush | +14 1 function changed, 14 bytes added net/ipv4/tcp.c: tcp_setsockopt | -5 tcp_sendpage | -25 tcp_sendmsg | -16 3 functions changed, 46 bytes removed net/ipv4/tcp_input.c: tcp_try_undo_recovery | +3 tcp_try_undo_dsack | +2 tcp_mark_head_lost | -12 tcp_ack | -15 tcp_event_data_recv | -32 tcp_rcv_state_process | -10 tcp_rcv_established | +1 7 functions changed, 6 bytes added, 69 bytes removed, diff: -63 net/ipv4/tcp_output.c: update_send_head | -9 tcp_transmit_skb | +19 tcp_cwnd_validate | +1 tcp_write_wakeup | -17 __tcp_push_pending_frames | -25 tcp_push_one | -8 tcp_send_fin | -4 7 functions changed, 20 bytes added, 63 bytes removed, diff: -43 built-in.o.new: 18 functions changed, 40 bytes added, 178 bytes removed, diff: -138 Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Uninline tcp_done().Andi Kleen
The function is quite big and has several call sites and nothing to collapse by compiler optimization on inlining. Besides it's nicer to read in a in .c file. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET]: Treat CHECKSUM_PARTIAL as CHECKSUM_UNNECESSARYHerbert Xu
When a transmitted packet is looped back directly, CHECKSUM_PARTIAL maps to the semantics of CHECKSUM_UNNECESSARY. Therefore we should treat it as such in the stack. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[SK_BUFF]: Introduce tcp_hdr(), remove skb->h.thArnaldo Carvalho de Melo
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Abstract out all write queue operations.David S. Miller
This allows the write queue implementation to be changed, for example, to one which allows fast interval searching. Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[NET]: Convert xtime.tv_sec to get_seconds()James Morris
Where appropriate, convert references to xtime.tv_sec to the get_seconds() helper function. Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Add two new spurious RTO responses to FRTOIlpo Järvinen
New sysctl tcp_frto_response is added to select amongst these responses: - Rate halving based; reuses CA_CWR state (default) - Very conservative; used to be the only one available (=1) - Undo cwr; undoes ssthresh and cwnd reductions (=2) The response with rate halving requires a new parameter to tcp_enter_cwr because FRTO has already reduced ssthresh and doing a second reduction there has to be prevented. In addition, to keep things nice on 80 cols screen, a local variable was added. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP]: Add RFC3742 Limited Slow-Start, controlled by variable ↵John Heffner
sysctl_tcp_max_ssthresh. Signed-off-by: John Heffner <jheffner@psc.edu> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP] FRTO: Entry is allowed only during (New)Reno like recoveryIlpo Järvinen
This interpretation comes from RFC4138: "If the sender implements some loss recovery algorithm other than Reno or NewReno [FHG04], the F-RTO algorithm SHOULD NOT be entered when earlier fast recovery is underway." I think the RFC means to say (especially in the light of Appendix B) that ...recovery is underway (not just fast recovery) or was underway when it was interrupted by an earlier (F-)RTO that hasn't yet been resolved (snd_una has not advanced enough). Thus, my interpretation is that whenever TCP has ever retransmitted other than head, basic version cannot be used because then the order assumptions which are used as FRTO basis do not hold. NewReno has only the head segment retransmitted at a time. Therefore, walk up to the segment that has not been SACKed, if that segment is not retransmitted nor anything before it, we know for sure, that nothing after the non-SACKed segment should be either. This assumption is valid because TCPCB_EVER_RETRANS does not leave holes but each non-SACKed segment is rexmitted in-order. Check for retrans_out > 1 avoids more expensive walk through the skb list, as we can know the result beforehand: F-RTO will not be allowed. SACKed skb can turn into non-SACked only in the extremely rare case of SACK reneging, in this case we might fail to detect retransmissions if there were them for any other than head. To get rid of that feature, whole rexmit queue would have to be walked (always) or FRTO should be prevented when SACK reneging happens. Of course RTO should still trigger after reneging which makes this issue even less likely to show up. And as long as the response is as conservative as it's now, nothing bad happens even then. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-04-25[TCP] FRTO: Moved tcp_use_frto from tcp.h to tcp_input.cIlpo Järvinen
In addition, removed inline. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-02-08[TCP]: remove tcp header from tcp_v4_check (take #2)Frederik Deweerdt
The tcphdr struct passed to tcp_v4_check is not used, the following patch removes it from the parameter list. This adds the netfilter modifications missing in the patch I sent for rc3-mm1. Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2007-01-04[TCP]: Use old definition of beforeGerrit Renker
This reverts the new (unambiguous) definition of the TCP `before' relation. As pointed out in an example by Herbert Xu, there is existing code which implicitly requires the old definition in order to work correctly. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-22[TCP]: Fix ambiguity in the `before' relation.Gerrit Renker
While looking at DCCP sequence numbers, I stumbled over a problem with the following definition of before in tcp.h: static inline int before(__u32 seq1, __u32 seq2) { return (__s32)(seq1-seq2) < 0; } Problem: This definition suffers from an an ambiguity, i.e. always before(a, (a + 2^31) % 2^32)) = 1 before((a + 2^31) % 2^32), a) = 1 In text: when the difference between a and b amounts to 2^31, a is always considered `before' b, the function can not decide. The reason is that implicitly 0 is `before' 1 ... 2^31-1 ... 2^31 Solution: There is a simple fix, by defining before in such a way that 0 is no longer `before' 2^31, i.e. 0 `before' 1 ... 2^31-1 By not using the middle between 0 and 2^32, before can be made unambiguous. This is achieved by testing whether seq2-seq1 > 0 (using signed 32-bit arithmetic). I attach a patch to codify this. Also the `after' relation is basically a redefinition of `before', it is now defined as a macro after before. Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Fix assorted misannotations (from md5 and udplite merges).Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Annotate __skb_checksum_complete() and friends.Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Annotate csum_tcpudp_magic() callers in net/*Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[TCP]: MD5 Signature Option (RFC2385) support.YOSHIFUJI Hideaki
Based on implementation by Rick Payne. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[TCP]: Restrict congestion control choices.Stephen Hemminger
Allow normal users to only choose among a restricted set of congestion control choices. The default is reno and what ever has been configured as default. But the policy can be changed by administrator at any time. For example, to allow any choice: cp /proc/sys/net/ipv4/tcp_available_congestion_control \ /proc/sys/net/ipv4/tcp_allowed_congestion_control Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[TCP]: Add tcp_available_congestion_control sysctl.Stephen Hemminger
Create /proc/sys/net/ipv4/tcp_available_congestion_control that reflects currently available TCP choices. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-12-02[NET]: Size listen hash tables using backlog hintEric Dumazet
We currently allocate a fixed size (TCP_SYNQ_HSIZE=512) slots hash table for each LISTEN socket, regardless of various parameters (listen backlog for example) On x86_64, this means order-1 allocations (might fail), even for 'small' sockets, expecting few connections. On the contrary, a huge server wanting a backlog of 50000 is slowed down a bit because of this fixed limit. This patch makes the sizing of listen hash table a dynamic parameter, depending of : - net.core.somaxconn tunable (default is 128) - net.ipv4.tcp_max_syn_backlog tunable (default : 256, 1024 or 128) - backlog value given by user application (2nd parameter of listen()) For large allocations (bigger than PAGE_SIZE), we use vmalloc() instead of kmalloc(). We still limit memory allocation with the two existing tunables (somaxconn & tcp_max_syn_backlog). So for standard setups, this patch actually reduce RAM usage. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-08-02[TCP]: SNMPv2 tcpAttemptFails counter errorWei Yongjun
Refer to RFC2012, tcpAttemptFails is defined as following: tcpAttemptFails OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of times TCP connections have made a direct transition to the CLOSED state from either the SYN-SENT state or the SYN-RCVD state, plus the number of times TCP connections have made a direct transition to the LISTEN state from the SYN-RCVD state." ::= { tcp 7 } When I lookup into RFC793, I found that the state change should occured under following condition: 1. SYN-SENT -> CLOSED a) Received ACK,RST segment when SYN-SENT state. 2. SYN-RCVD -> CLOSED b) Received SYN segment when SYN-RCVD state(came from LISTEN). c) Received RST segment when SYN-RCVD state(came from SYN-SENT). d) Received SYN segment when SYN-RCVD state(came from SYN-SENT). 3. SYN-RCVD -> LISTEN e) Received RST segment when SYN-RCVD state(came from LISTEN). In my test, those direct state transition can not be counted to tcpAttemptFails. Signed-off-by: Wei Yongjun <yjwei@nanjing-fnst.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-07-08[NET] gso: Fix up GSO packets with broken checksumsHerbert Xu
Certain subsystems in the stack (e.g., netfilter) can break the partial checksum on GSO packets. Until they're fixed, this patch allows this to work by recomputing the partial checksums through the GSO mechanism. Once they've all been converted to update the partial checksum instead of clearing it, this workaround can be removed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-30[NET]: Generalise TSO-specific bits from skb_setup_capsHerbert Xu
This patch generalises the TSO-specific bits from sk_setup_caps by adding the sk_gso_type member to struct sock. This makes sk_setup_caps generic so that it can be used by TCPv6 or UFO. The only catch is that whoever uses this must provide a GSO implementation for their protocol which I think is a fair deal :) For now UFO continues to live without a GSO implementation which is OK since it doesn't use the sock caps field at the moment. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-29[NET]: Added GSO header verificationHerbert Xu
When GSO packets come from an untrusted source (e.g., a Xen guest domain), we need to verify the header integrity before passing it to the hardware. Since the first step in GSO is to verify the header, we can reuse that code by adding a new bit to gso_type: SKB_GSO_DODGY. Packets with this bit set can only be fed directly to devices with the corresponding bit NETIF_F_GSO_ROBUST. If the device doesn't have that bit, then the skb is fed to the GSO engine which will allow the packet to be sent to the hardware if it passes the header check. This patch changes the sg flag to a full features flag. The same method can be used to implement TSO ECN support. We simply have to mark packets with CWR set with SKB_GSO_ECN so that only hardware with a corresponding NETIF_F_TSO_ECN can accept them. The GSO engine can either fully segment the packet, or segment the first MTU and pass the rest to the hardware for further segmentation. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23[NET]: Add software TSOv4Herbert Xu
This patch adds the GSO implementation for IPv4 TCP. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-06-23[NET]: Merge TSO/UFO fields in sk_buffHerbert Xu
Having separate fields in sk_buff for TSO/UFO (tso_size/ufo_size) is not going to scale if we add any more segmentation methods (e.g., DCCP). So let's merge them. They were used to tell the protocol of a packet. This function has been subsumed by the new gso_type field. This is essentially a set of netdev feature bits (shifted by 16 bits) that are required to process a specific skb. As such it's easy to tell whether a given device can process a GSO skb: you just have to and the gso_type field and the netdev's features field. I've made gso_type a conjunction. The idea is that you have a base type (e.g., SKB_GSO_TCPV4) that can be modified further to support new features. For example, if we add a hardware TSO type that supports ECN, they would declare NETIF_F_TSO | NETIF_F_TSO_ECN. All TSO packets with CWR set would have a gso_type of SKB_GSO_TCPV4 | SKB_GSO_TCPV4_ECN while all other TSO packets would be SKB_GSO_TCPV4. This means that only the CWR packets need to be emulated in software. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>